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1080p video partly pixled after rendering
So I'm pretty new to video production and I'm struggling with properly rendering 1080p game footage. My main problem is that multiple frames of the output video are pretty pixled, looking like this

I'm working with footage recorded using fraps and I'm editing with Sony Vegas pro 12 atm.
My project settings are matched to the footage I'm using in this particular project:

No doubt I messed up the rendering options somehow, since the raw footage looks okay. Here are the render settings I used for the shown output:

Can someone help me get those pixled scenes out of the video? Desired output format is MP4 since it seems easier to handle for youtube uploads.
Thanks in advance, I hope someone can help me with this.
Best regards,
Rickyfox

Edit:
I just discovered that about a minute of the output video just turned out black with the scene settings being exactly the same as the rest - anyone have a clue what that could be?

It honestly looks like something got corrupted with your export.  Have you tried encoding it more than once?  12 megabits per second with a 24mpbs peak should be more than sufficient for high quality 1080p video.  If anything, it may be excessive.  The quality you are getting looks more like what I'd expect at sub-1 mbps video for this quality level.  As an aside, it is worth noting that 2 pass will produce better results, thought it will extend encoding time.
One other thought is to try watching it in more than one viewer.  It is possible that the viewer you are using is struggling to decode the high data rate fast enough which could also result in the block issues you are seeing.  Basically, it looks like some of the blocks in the H.264 file are not encoding or decoding properly and that either means file corruption or insufficient decoding speed.
I guess to rule out data rates, you could try increasing it to 30mbps with 45mpbs peaks.  It shouldn't have to be that high (that's the high end of bluray data rates), but it should rule out the data rate entirely.
Update: From some additional reading, I would try turning on 2-pass and turning on the deblocking filter.  It supposedly should help.

I did render the same footage with similar settings before and also received similar output, tho I cannot say it was the same output.
Edit: watched it with media player instead of vlc and it looks the same

@Rickyfox - how did it differ?  Were the distortions on different frames?

I no longer have the previous render here, so I can't say for sure if the errors occured on the same frames. What I can say for sure is that there were these pixled frames in a previous render with similar settings.

@Rickyfox - take a look at my most recent update.  Doing some more reading, it sounds like that particular encoder may need you to do 2 pass and use the deblocking filter.  It apparently can have some motion related issues with the encoding.

@Rickyfox - no, on the screen with "Variable Bit Rate" there is a "Two Pass" checkbox.  This means that it runs through the video once to figure out where it needs to use the most data and then encodes according to the calculations from the first pass.  Basically, VBR works by trying to approximate how much data to use based on how much change their is.  Two pass makes a better approximation instead of simply guessing (which can result in insufficient data left over for some really high motion scenes.)

Okay thanks so far AJ, I've adjusted my settings and let it render, we'll see if that solves the problem

Okay as far as I can tell two-pass and deblocking filter did the trick, I'll render the rest of the movie overnight and accept your answer if everything runs smoothly ;) Thanks lad


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What are the negative effects (if any) for leaving a prosumer comcorder powered 24hrs a day?
I have a use case where I need to leave a pro-sumer camcorder, (Let's say a Canon XA10) powered 24 hours a day indefinitely. The HDMI out of the camera would be used for monitoring 24 hours a day, but no recording would be done, and the LCD and viewfinder can stay turned off.  Additionally, other mechanical functions like auto focus can be disabled.
Are there any negative effects on the camera to leaving it on and powered for extended periods of time?

While there would not be any immediate adverse affects in the long run it will "burn" itself out. On the prosumer varaiety (Canon XA10) was NOT made to say on 24/7. It was made for broadcast videos and "on/off" use like shooting documentaries or news-like vids. Like LCD screens if you have the CMOS sensor on a fixed static shot for an extended time you could literally "burn" the scene onto the sensor. Also, the generated heat [and there will be heat] could eventually wear out the C-chips [resistors and whatnot. . . ]. The ideal operating temperature for the XA10: 32-104°F (0-40°C), 85% relative humidity.
Instead I would suggest a "cheap" security cam instead. Not as big and not as intrusive. AND you can leave it on 24/7.

There could be some consequences to using the Canon XA10 24/7, although I don't think they are very likely to happen.
I can think of two things that might go wrong:

Even tough the LCD is off, the CMOS sensor inside is still working. This can generate significant heat and cause an overheat. However, most cameras have a built in protection that shuts them down in case of overheating, so it's not a real risk.
Depending on what you will be shooting it is possible that the sun will shine directly through the lens on the sensor for a long time. There's some debate on this on the Photo.SE site, but some think this can damage your sensor.

I don't think there will be any real consequences. Normally I would cite overheating, LCD life reduction, etc. as consequences, but since most of the functions (including LCD) will be off and no actual recording will be taking place, it would seem that the number of moving parts that would be active would be very few.

Thanks for the input.  Those were my inclinations as well.

source: Stack Exchange

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Workflow for trimming, encoding, and publishing videos to the web
Basically, companies will be giving us access to a variety of videos in a variety of formats.  We will then download the videos, trim out the important part in a 5 min and/or 10 min chunk.  From there, we want to encode the video to a variety of web (mp4) qualities. Initially we will only have 1, maybe 2 people doing the process.
Workflow:

Download video to local computer
Import video to Vegas Movie Studio
Trim video & export to the highest quality we'll be publishing at

.

Place video in local watch folder for a local encoder (Sorenson Squeeze Desktop) which will encode the video to the pre-defined outputs.

OR

Manually upload videos to a server that is being watched by Zencoder/Encoding.com/Sorenson Server which will encode the video to the pre-defined outputs and sends to main server.

.

Main server watches for completed encodings and automatically publishes them on the site as we please.

There are a few issues I see with this workflow.  First off, we are re-encoding the video after trimming, then encoding it AGAIN to all of the desired outputs.  And second, the issue of uploading all of the files from a local computer to a server could be time consuming depending on the upload speed.
Is there a better, more time efficient, and/or more money saving workflow to this?

If you are willing to use Adobe products, Premiere supports direct integration with Adobe Media Encoder and can be set with presets that include multiple output formats and sizes.  Each encoding runs off the actual main project, thus you remove the extra generation of loss.
Alternately, using a lossless quality intermediate file will prevent issues as no additional quality will be lost going from the source material to the intermediate output.
A big pipe is the only answer to the second problem.  Encoding to the final format locally will save on bandwidth, but you have to transfer the file at some point and final output is the smallest amount of data possible unless you are making an awfully large number of different sizes of each video.

+1 for lossless intermediate format. It doesn't have to be mathematically lossless; a high-quality visually lossless format like ProRes should suffice for this process.

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Adobe Premiere CS6 search slidebar
CS6 has made it easier for me by making me have to use the keyboard to fast forward without having to hold it, but i preferred the control of being able to use the sort of slidebar.
Does anybody know a way to get this sliding bar speed controller back?

This feature was completely removed in CS6. However, you can now use the keys J, K, and L to scrub the footage.

Why on earth would they remove this feature. It was fantastic. This combined with no audio on certain files that worked in 5.5 means I'll be sticking with 5.5 sadly. Also, you could use these hot keys in early versions of premier.


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FFMPEG output is blocky
I'm attempting to extract the individual frames from a raw AVC video stream. I'm doing this via the following ffmpeg command: ffmpeg -q 1 -i video_test.avc -f image2 frames/frames_%04d.jpg
The problem I'm encountering is the first few frames look good. I'm including an example below.

The extracted frames then get progressively worse and by the time I get to the 17th frame, they're really blocky.

You get get the raw video from this link.
Is there an option I'm missing? I've noticed that FFMPEG on my Mac works as expected and generates nice frames, but FFMPEG on my production server that runs Ubuntu exhibits this problem.

Does it improve each time a keyframe is reached or does it continue to get worse indefinitely?

Once it gets to the blocky state, it stays at that blocky state indefinitely. It doesn't get worse.

Have you tried different versions of FFMPEG to see if it is just a bug in the particular version?  Sorry, just throwing out random troubleshooting thoughts.  I'm not aware of anything specific to this problem.

I'm using the binaries from the repository listed on http://ffmpeg.org/download.html. This gets updated somewhat frequently and the last update was on July 15th. I'll try building it from source tomorrow and see if that changes anything.

Option placement matters

Is there an option I'm missing?

No, but option placement matters. Options before the input apply to the input, and options before the output generally apply to the output. The exception are global options. See the FFmpeg synopsis and FFmpeg description for more details on option placement.
Therefore, you must move your -q (alias for -qscale) option:
ffmpeg -i video_test.avc -q:v 2 frames/frames_%04d.jpg

-f image2 is superfluous here since ffmpeg knows that your outputs are images.
A sane range for -q:v for the encoder mjpeg is 2-5; lower is higher quality.
It is recommended to be explicit as to which stream you want to apply -q to since ffmpeg can not know if it should be applied to video or audio, so in your case use -q:v. This is good practice, although it does not matter for your input since you have no audio.

A fake "ffmpeg"

I've noticed that FFMPEG on my Mac works as expected and generates nice frames, but FFMPEG on my production server that runs Ubuntu exhibits this problem.

Ubuntu no longer uses FFmpeg:

Who can tell me the difference and relation between ffmpeg, libav, and avconv?
The FFmpeg/Libav situation

Since I do not use the fork my answer may not work for you.
Getting ffmpeg
FFmpeg development is very active and it is always a good idea to use a recent version. Two main ways of getting it are:

Follow a step-by-step guide to compile ffmpeg
Use an already compiled ffmpeg build (instructions)

It was the placement of the -q 1 that did it. Thanks.


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Cross Dissolve not available in between clips [Premiere CS6]
I'm trying to add a cross dissolve effect in between two clips. Premiere doesn't allow me to do it between the first and the second clip.
Does anyone know the reason?

Do your clips have overlap?  If you put the clips end to end, running them right up to the end of the file and beginning of the file, then there is no video for Premiere to apply a dissolve to.  You need to have sufficient video left in the clip to complete the transition.


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Export to wide screen (16:9) from Final Cut pro X
Apologies for the noob question but I've just started trying to learn FCP and couldn't find the settings to export my movie in 16:9 aspect ratio.
Can anyone tell me the quickest way to go about it?
(source material has a variety of different aspect ratios)

This answer assumes that the video that you're editing is already in a 16:9 ratio, otherwise when you export there will be black bars on the sides or above and below your video.
A 16:9 ratio is the standard for HDTV and Full HD. You're probably familiar with the Youtube video qualities - 360p, 480p, 720p, 1080p, etc. These are all 16:9. Therefore, all you have to do is export in one of these resolutions - 1080p is Full HD and 720p is HD.
For more reading on common aspect ratios, reference this Wikipedia page.

Thanks. I'm away from my FCP machine just now but will hopefully be able to have a look later on tonight.

Finally got a chance to fire up FCP and noticed it's in the initial project set up requester.


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Do I need to convert 60fps to 30fps so it will be reproducible?
I just bought a GoPro Hero 3 Black Edition.  I have been testing out two modes: 1080p at 30fps and 720p at 60fps.
I have noticed that when reproducing the videos with 720p at 60fps they are not really smooth, they seem a little bit weird (I have used VLC to reproduce them). So, a friend of mine suggested me to convert them to 30fps and then they will be slow motion, and later on speed them up 50% with Adobe Premier.  After doing that, they look better.
I am confused. Why does this happen? Why do I need to low them down to 30fps and then speed them up up to 50%? Wouldn't that mean that we are back to 60fps?
Thanks

You're not back to 60fps, you're still at 30fps but with every other frame discarded (or blended, or interlaced, depending on how the speedup is accomplished).
When you discard every other frame, you're trading off temporal resolution. If you interlace, you're trading off spatial resolution.
Either way, if this appears smoother, something's wrong with the way the 60fps is being presented. Your playback system may not be able to keep up with the data rate or frame rate. If 1080/30 looks OK, then it's probably not a data rate issue.

My first guess would be that perhaps your screen is incapable of a 60hz refresh.  If you have a slower screen refresh or frame rate, then it could result in some odd visual artifacts when trying to view the video at 60fps.
As Jim described, the slowing it to 30fps and then increasing the speed is still a 30fps video, you just discarded half the frames, so that's why it looks like your 30fps shot did.  I would look in to the capabilities of your video card and monitor to see if there might be a problem there.  Also keep in mind that unless your player supports frame synchronization, it is possible that even a 59 or 60hz screen might be insufficient to play it back if the video isn't loaded in to the buffer by the time the screen goes to refresh.  This would result in dropped frames.  The same thing can happen at lower frame rates, but if the screen refreshes more often, then the frame still gets displayed, just for a shorter time.


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Creating a particle system explosion without a collision
I have recently discovered a tutorial about 3DS Max on Youtube that explains (in one of its parts) the creation of an explosion with a PF Source.
I am trying to create the same explosion but for a different scene and scope. My explosion should begin suddenly and without a collision to happen. I followed those steps but I discovered that they don't work in my case.
More information: I have an extruded text (converted into an editable poly object) that is required to explode at the 450th frame in my animation.
How can I create this explosion?

If you want to use a physics simulation, your best bet is to have a collision but don't render the object that collides.  I haven't used 3DSMax personally in a number of years, but there should be an option to have the object physically impact the scene but not be rendered by the render engine itself.  Then you simply do the collision to occur at frame 450 and it should behave the way you want as it does in the tutorial you are following.

your idea is great. I will try it tomorow when I am in front of my coputer, but it looks like being what I need.


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Minimal working frame rate for H264 codec
When making a video from single image files whereas each image file should be visible for about one second, it does make sense to encode a video with an extremely low frame rate such as 1 frame per second. For this type of application, every frame rate greater than this would be a waste of resources.
I am wondering if the H264 codec (or any specific implementation, such as x264) itself has any lower limit for the frame rate below which it comes to technical problems or some kind of instabilities. In case there is no problem with encoding, can we expect video players to properly deal with such an unusual low frame rate?
Thanks for sharing your experience!

Also see: Producing stable video from slow images with FFmpeg and FFmpeg for animation of image files outputs all-black video.

I'm with AJ. Unless you know the characteristics of every player that might view this, it would be unwise to rely on a small sample of test results. Using a standard frame rate like 24 fps with a keyframe interval of 24 frames will give you essentially the same thing with no compromise in compatibility. The intermediate frames will be minimally small because there will be no detectable changes to encode.

yup, a bit-identical frame only takes about 15 bytes.  All macroblocks = skip, and CABAC compresses the repeated bit pattern for that very well.

I'd only worry about hardware players that are assuming they'll output to a 60 or 50Hz TV signal, though.  h.264 doesn't care about timing, it's just frames, even in a VFR video.  Frame timestamps is a container issue.  Container formats are very flexible.  It's easily possible to have a single frame shown for 1 minute, then 150fps for several frames, then another frame shown for a while, or anything you like.  Storing VFR video in mkv, mp4, and some other modern containers is a solved problem.

I'm not sure how it will behave at very low frame rates, but it is worth pointing out this would also limit your options on how and when you could change frames since they would have to follow on the clock cycles.  What is more likely to work in this case is a long keyframe interval.  The majority of frames in a compression like H.264 only store the changes from the previous frame.  In the case of a still image, the compression ratios will be huge because very little (no) change occurs between frames.  I'm not sure that you would really pick up enough of a savings from dropping the frame rate to be worth the loss of control over when you can make a change to the frame.
The best bet would be to try it with your media and see the results.  Compression is a highly content dependent thing and the best quality and compression for any particular clip is going to depend a lot on the nature of that clip, so trial is still the best way to test it out.

There is a compression downside beyond what my earlier comment on another answer said: If there is much redundancy between the different images (i.e. it's still a video, not a slideshow), padding with identical images will make it harder for the encoder to find and exploit that. Depending on encoding settings, the encoder will only keep some number of old frames as possible references for new frames, and can only search within a GOP (e.g. default 250 frames for x264).  If all those candidates are the same image, that doesn't give it multiple options to find a better reference for each block...

... e.g. after a foreground object moves in front of some background detail, the encoder can save bits by referencing what it looked like in an older frame before it was obscured.  h.264 can choose reference frames on a per-block basis.  This is a relatively small effect; good h.264 encoders do ok with only 1 reference frame, but it's still somewhat harmful to compression efficiency

Sure, you still need proper encoding settings, but you can grow your GOP size rather than reduce your frame rate if things are all that static.  If they aren't, then dropping frame rate isn't a great option to begin with.  I wonder if there has been any work on a variable GOP format.

I think repeated images are still going to reduce the opportunity for useful B-pyramid and multiple reference P-frames options.  But I guess an encoder can keep an old P frame from anywhere within the GOP so losing out on reference B-frames is probably all in theory, but IDK about in practice.

Most formats are variable GOP, and any good encoder will use that!  x264's default is to opportunistically end GOPs on scenecut detection, inserting an IDR frame.  (keyint=250 is the max GOP length.  keyint_min=25 is the minimum interval so it won't insert another keyframe even if it thinks it sees another scenecut; there are tuning options for scenecut bias, etc.)  x265 even has an extra GOP-lookahead parameter for opportunistically extending a GOP.  https://x265.readthedocs.io/en/default/cli.html#cmdoption-gop-lookahead.  And of course adaptive B-frame decisions are on by default

Nice, amazing how much they've advanced since I last got in to the real nitty gritty of encoders.  I keep a high level overview but my last extreme deep dive was mpeg 2 era...  Might be time to do another deep dive on h265 though.

Good MPEG-2 encoders can make keyframe decisions based on scenecuts, and P vs B frame decisions based on content. :P  ffmpeg's mpeg2video encoder lists a -sc_threshold option, and a -b_strategy option to control I/P/B selection strategy.  But anyway, h.265 is neat, with up to 32x32 DCT blocks, and very large 64x64 prediction units which can break down into smaller blocks if needed. https://sonnati.wordpress.com/2014/06/20/h265-part-i-technical-overview/.  vs. h.264 16x16 macroblocks with only 4x4 or 8x8 (high profile only) DCT blocks.  Also https://forum.doom9.org/showthread.php?t=167081

I've played around with turning a bunch of still photos into a h.264 slideshow, mostly to compare the compression efficiency of JPG vs. h.264.  I got some useful replies about the technical implications of this from x264 devs on doom9.  e.g. force x264 to not use B frames for this, because not-very-related images will need a lot of I macroblocks, and coding them in B frames is more expensive.
Software player behaviour with low-fps video isn't ideal, in the past.  I think one older player only checked for keyboard input when it displayed a frame.  So there was lag between user input and player response.  mplayer2 and mpv don't have this problem.  Also, players that can only seek to keyframes will seek in really large chunks (2 minutes or so!) if you don't reduce the keyframe interval.  x264 won't insert IDR (GOP boundaries) all over the place if the images are somewhat related to each other.
Use x264 -tune stillimage.  It cranks up the psy optimizations, because temporal stability isn't an issue for this use-case.  Further search results: from google.
I'd agree with other suggestions to have some duplicated frames, to bring the FPS up to at least 5 or something, just in case of bad players.  However, smartphones / tablets should have no problem playing variable-FPS video, since they usually record that way when light levels drop.  Since variable-FPS videos from phones are now out there, hardware player support for them should be expected.  I wouldn't expect problems, but I also wouldn't be surprised if there at least some old hardware players that don't handle it well.
A frame of all "skip" macroblocks only takes about 20bytes at 1080p, IIRC.  One reason I don't like duplicated frames, though, is that it interferes with single-stepping to go through the images manually.

There is a compression downside to duplicating frames, though: If there is much redundancy between the different images (i.e. it's still a video, not a slideshow), padding with identical images will make it harder for the encoder to find and exploit that.
Depending on encoding settings, the encoder will only keep some number of old frames as possible references for new frames, and can only search within a GOP (e.g. default 250 frames for x264).  If all those candidates are the same image, that doesn't give it multiple options to find a better reference for each block.
e.g. After a foreground object moves in front of some background detail, the encoder can save bits by referencing what it looked like in an older frame before it was obscured.  h.264 can choose reference frames on a per-block basis.  This is a relatively small effect; good h.264 encoders do ok with only 1 reference frame, but it's still somewhat harmful to compression efficiency, and a waste of power / battery life / CPU time on the decompression side to copy memory around decoding and displaying extra frames.

Recovering VFR after an NLE forces all your clips to some high frame rate:
FFmpeg has an mpdecimate filter that drops similar frames.  You can set limits on how many frames in a row it can drop.  With a tight similarity threshold, you should get it to only drop actual duplicates.
e.g. ffmpeg -i input.mp4 -vf mpdecimate=max=9:hi=400 -c:a copy -c:v libx264 -preset veryslow -tune film output_vfr.mkv drops up to 9 frames in a row, and only if the most-different block was different under "400", and (defaults): no more than 33% of the blocks were different by "320" units.  IIRC, it's basically an 8x8 SAD on pixel components.
(FFmpeg defaults to CFR for .mp4 outputs, though, so use -vsync 2 for variable-frame-rate .mp4 output.  I think that's safe: Problems with frame rate on video conversion using ffmpeg with libx264)

Most NLE's will allow you to import a still image in the form of how long you want it to appear in the timeline assuming you have set the project properties to some standard frame rate such as 30 fps or 24 fps etc.
In Vegas Pro I can set the time a still picture should appear on the timeline, from a fraction of second to several seconds. If I set this to 1 second then when I drag and drop a still image in the timeline, Vegas will generate enough frames to meet my request. I usually edit with 30 fps videos, and when I add a still picture I am mixing a timeline with 30 fps video that is already there (AVCHD 1080p).
To give you a specific answer, I would need to know what NLE you are using.

I just apply a raw encoding software such as ffmpeg or avconv, so no need to talk about any NLE. I think the question is pretty much answered with "Just go by a standard frame rate which all players can deal with properly. There is no real 'waste of resources', because the encoding scheme is good enough to efficiently deal with still images".

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Very Shaky camera but a constant background
I recorded a video of a speaker at a graduation ceremony using my tablet. The first half of the recording, I held the tablet in my hand so it's shaky and just terrible. I finally realized that I could capture the scene I wanted just fine by using the tablet's stand and placing it on the ground.
Throughout the entire video, the background never changes, the speaker is at a podium and it can act as a focal point...other than the speaker, there is no motion in the scene (other than audience heads in the foreground.
I tried to use After Effects Motion Warp but it looks horrid but it would work perfectly if I could select a "static background" from one frame and apply that throughout the rest of the video.
Is something like this possible?

While it's fairly easy for it to figure out the camera position from the shot, it is not nearly as easy for it to identify subjects cleanly.  In order to do what you are talking about, the subject would have to be identified and extracted from the background without any extra bits coming along.
Computer vision algorithms simply aren't that advanced yet and such work is always either done by rotoscoping (manually outlining the subject on each frame) or using a chroma or luma key backdrop that can be removed.  Stabilization works by identifying straight lines and tracking them generally.  The border fill in motion warp then works by attempting something similar to what you are talking about by looking at what appeared to be there in previous frames, but it doesn't really work all that well yet either as it is a new technology.
The same problems that prevent them figuring out accurately what was there in previous frames are what prevent separating the subject from the background (the ability to identify, with precise accuracy, the same object in one image to another.  You would end up with a subject that hovered oddly on the background and had a ring of background around them and/or left bits of them behind if you tried it with current level of technology.
Using motion warp and applying a crop or bypassing the auto-crop and manually cropping and moving around the frame is probably your best bet.  This is how I usually handle stabilization issues.

I was trying to use motion warp with crop but it would not allow, saying it would have excessive cropping. I'm fine with a 480p video, but it won't even give me the option.

@MikeBrown - what I'm saying is to do it without the auto-scale/auto-crop and then do it manually.  Basically you end up with a video where the objects don't move, but the scene will move in and out of frame.  You then have to manually set up keyframes for motion to keep the screen full of image.  The auto-crop and auto-scale tend to waste far more of the image than actually has to be wasted if you take the time to do your own cropping and scaling on the stabilized video.

Do you mean frame by frame cropping? or do you mean use the stabilizer then crop to the consistent area? I'm VERY new to this, the last I worked with Premiere was in 2000 converting VHS tapes to digital video.

@MikeBrown - you have select a viewable area from the video that the video doesn't move out of and then you use keyframes to adjust it to keep the viewpoint within the original image.  When you stabilize, the result is that the image subject stays still, but the image edges move around it.  You have to keep a crop that is within the area for which you have image and do so by adjusting the scale of the stabilized layer and adjusting it's position (via keyframes) to make gentle, smooth movements that keep the image covering the entire area on screen.

Deshaker which is a filter that can be applied in Virtual Dub, could fix the original shaking some, on mostly default settings (where the background moves).
Dehaker also has many many settings possible, you could mask out areas , as long as the person moving was then larger than the masked out area, and you got the settings all correct, it might be able to fix some of that up for you.
In most situations of any EIS (electronic image stabilization) It is cropping up a smaller portion of the whole video, and the methods for filling in where there is no picture at all (borders) are not great.
I find that setting everything and testing by looking at the vectors, using a excessive ammount of smoothing, and then using only about 1/2 of what would completly fix it , works ok to make the pictures a little more viewable.


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Why there are no full lenght independent cartoon animated movies created in Blender?
I have been searching for an indie movie that is completely done in Blender, but the longest animation I have found was about 15 minutes long.
Are there any full length animated cartoons/movies (~90 minutes)?
I have found only this:
http://www.blender.org/features-gallery/movies/
You can tell me also commercial titles if there are any, but I haven't found any so I am interested if they are any or not?
Most of the movies from big studios are using Maya, so I am curious if any indie companies are using Blender or not, because I think that if a group of enthusiasts invest 2 or 3 years in something like Big Buck Bunny (it's only 10 minutes long, but created in Blender and I think it is really nice ely done, especially if you consider it was done about 5 years ago):

This question is running very close to the "no actual problem to be solved" variety discouraged in the types of questions to avoid asking on the help page.  Also, it's a bit unclear what you're asking, apart from the title.

@JoshP Why there are no full lenght independent cartoon animated movies created in Blender? Could you explain it somehow?

I cannot... not my area of expertise.  I had mentioned the "unclear" bit, as that is another of the criteria to watch out for, for off-topic questions.

@JohnRygielski, http://blender.stackexchange.com/

@JoshP wow, finally an exchange for Blender. Can you please move it there, if you are a moderator? Thanks.

@Derfder, I asked... the blender mods didn't want the question.  I'm not sure they have video embedding either.

Simply put, to make a full length movie requires a lot of man hours and generally a decent budget.  It becomes more cost effective to get real animation software when dealing with a full length film than trying to struggle through with something like Blender.
Don't get me wrong, Blender is great for what it is as a free product, but, at least as of the last time I was able to seriously work with it a few years back, it was nothing at all compared to the capabilities of one of the high end systems like Maya or SoftImage.
Both the ease of working with the tools and the improved collaboration workflows make it so that using a commercial system may likely be cheaper in the long run due to time saved for a long project like a full length movie.  It's certainly easier, even if costs are just close to comparable.
It's also worth noting that Maya isn't the only platform used by the big studios.  Several use their own in-house systems, Maya, SoftImage and Cinema4D are also all used pretty extensively.  3D Studio Max is also sometimes used, though it has found more of a niche in the video game market.

Thanks for your answer, but Blender can be e.g. altered if something is missing because it's opensource. So the indie comapny can create a specific tool. e.g. to generate same things programatically etc. so that can speed things up. You cannot do that with Maya, Max or others, because they are proprietary software. Btw. Blender is more intuitive and easier to work with than Maya.

@Derfder - not without considerable development effort and time.  You are talking feature sets that took man decades, if not man centuries, to build and polish and get working well.  It's both cheaper to buy the software and cheaper to do it the hard way than it is to implement the software features that would be needed.  Blender is a great project for people to play around with writing code for a 3d engine and modeling tool, but it is done for reasons of curiosity and interest in the software for the software's sake, not for reasons of trying to make an actual film.

@Derfder - also, you can extend any of the major software packages and every house out there does.  Custom generation utilities are produced, special effects packs are made, even entire custom workflows and menu systems are built.  Maya and SoftImage at least both give great ability for dev staff to easily leverage existing functionality in to new custom features.  The ease with which they can be extended actually is simpler than extending Blender in many ways since there is more existing functionality exposed to be able to work with.

@Derfder and Blender may be easier for a beginner to work with than Maya, but that's like saying Paint is easier to work with than Photoshop.  There is a lot of complexity to Maya and even more complexity to SoftImage, but to a trained artist, those features that are missing from Blender that make it "easier" actually make life substantially more difficult due to missing options and functionality that are needed to do the job well.

There actually are two films that I am aware of. One is 'Naught 5' and Plumiferos. You can easily Google to see the production websites.

Welcome to Video Production on Stack Exchange.  It is never too late to post an answer.  You can also use embedded links if you want in the titles to link to the websites for the projects you are talking about.

Blender is now in the actual version of 2.73 a huge competitor to all the big proprietary animation programs.
The problem is not even the software, but the budget for employing scriptwriters (most important, because the story is number one of the list for a successful movie), voice actors, designers, matte painters, rigging specialists, animators, musicians, compositors ... you would need a budget of several millions.
I have seen a movie done entirely in 3DS Max Studio. The "uberector" (that is the name for a person who makes a movie entirely alone), has switched now to Blender 3D because it's becoming better and better and reaching a point where you don't even think about to use Maya or Lightwave or whatever is on the market.
But the main problem remains always the same: Do you have a story for a full featured movie? Yes? Ok, then have you draw a storyboard for the 80 minutes of movie? Have you already the music? And have you asked you're friends and neighbors if they are willed to play a role as voice actors? If yes I guess you have spend the last 3 years only on this part of the movie making process. ... Only now comes the part of 3D animation, compositing, modelling, rigging, ... it's hard work indeed.

I have recently finished and released my third animated feature that I created entirely by myself, aside from the talent of my voice actors,  Cold Dark Mirror, which I created using Blender.  http://originalsineproductions.com/ColdDarkMirror.html
Other Uberectors working in blender:
Spooktergeist, who is working on his film "River of Dried Blood"

Klaus TehKurious, with "City of Dying Head"


text:
Is there a text effect for Sony Vegas Movie Studio for light reflecting off metal?
I found a picture to illustrate the effect I would like to have. http://www.bugei.com/scart/public/database/repository/images_import/peace/habuchi.jpg
Does anyone know of text effect for this, or another way to do it?

Vegas Movie Studio or Pro versions do not have a text option already set up for this but there are a couple of ways to get what you want.
One way is to make a composite by creating two video tracks one with the text and the other with the image you want to bleed through the text, here are instructions on how to do what is called a 'masking track':
http://www.sonycreativesoftware.com/creating_masking_tracks_in_vegas

Yes you can add this type of effect using light rays and lens flares on the text.  When I was first learning Vegas I did some YouTube searches to find tutorials. THIS video in particular gives you an idea of how to do what you are looking for I believe.


text:
Format of imported video files in Adobe Premiere
What is the format of newly imported file into the Adobe Premiere project? Evenmore, will the video be lossy encoded?

Premiere works with the source files you provide.  Depending on the format it may generate a lossy copy that can be used for faster preview in the editor, but final renders will work directly from your source files.  That's what's going on if you see it says it is conforming  files in the lower right corner.

Check the supported video formats of Adobe Premiere here. And i don't think it would loss some video quality because it's very powerful and professional, that's one of the reasons why people like to spend such much money for it.


text:
Clear and informative tutorial on video file formats
...I think I will want to make a tutorial that covers video file formats, and their relationship to video codecs.  There seems to always be a lot of confusion around these topics for emerging media creators.
Is there a good source for a tutorial that introduces beginners to the intricacies of this topic?
In particular, it would be good to explain best practices for encoding and exporting files for use during workflow on a single project (ie. many specialists preparing material for use by the primary editor on the job), and formats/codecs to use for mastering a BluRay or for upload to YouTube.
I see some snippets of the information available piecemeal from a variety of sources, but I'd love to discover one clear tutorial -- or at least several that could be used as a basis for a good comprehensive knowledge resource.
---v

I don't think you will find a single clear tutorial as you are talking about a very very broad field and talking about multiple aspects of it.  Many, many, many tutorials exist for help with encoding for YouTube or encoding for Bluray.  In fact, most Bluray authoring software has pretty good walkthroughs in their help.
Youtube itself outlines the basics for getting the best quality encoding for it here, provides conversion settings for unsupported formats here and has links to numerous videos related to creating videos here.
As for understanding file formats vs codecs, I don't know that a tutorial would be much help as it is a conceptual thing not something you can walk-through.  I generally tell people that a video file format is a bit like a filing cabinet, it gives the general organization, but doesn't define the data held within.  The codec is like the filing system and determines how the data the file format holds is stored.
As far as choosing what file format to use or codec, again, with so many to choose from, they really are better covered in tutorials about a specific need.  H.264 in general ends up being by far the most common these days and the file format itself is more or less irrelevant as long as it's using an H.264 codec since it's fairly simple to move an H.264 stream from one format to another.
Similarly, CBR vs VBR 1 pass vs VBR 2 pass is again really more of a conceptual thing rather than something a tutorial can cover.  Most people seem to get it ok when you simply describe video as a bunch of photos and say that CBR uses the same amount of data for every photo, regardless of how complicated the picture is, VBR 1 pass uses less when it notices that a photo is easy to store and more when it is hard and VBR 2 pass looks through all the photos first to make sure that it makes all the photos the overall best quality they can be by spreading the data around to where it's needed.
Ultimately though compression in and of itself is a field that people spend their entire careers in.  It is very deep and complex and you really aren't going to find an all inclusive tutorial to cover everything.  It simply doesn't exist.  The closest I've ever seen was actually the section on encoding in one of the Premiere Pro manuals (I think it was CS2, but it might have been Premiere Pro 6.5 (pre Creative Suite).) but that content is a bit dated now as that was DVD era and prior to H.264 really taking center stage for most purposes.

Well, the reason for my question is that in the absence of a clear, entry level tutorial, I'm ready to create one.  I'll look at the resources you cite, and I have not intention of trying to cover the matter in depth to the bottom of the issue.  What I see people struggle with is understanding just the basics. In CS6 or in Final Cut, the operator is presented with a dizzying array of choices. The conceptual matters you suggest are part of what should be in such a tutorial (not necessarily a "walkthrough"). Thanks for the references. I'll start there for source material.


text:
How do I communicate with post-production team? Need a list of effects and examples
I'm doing a short video and I am not from video editing background.
Sometimes I want to show my post production team the effect I want but it's very difficult to say... Just look at [...] video. I don't know where to find examples. Is there a list of names or example videos somewhere I can easily refer to?
For example, if I say I want Ken Burns effect for this photo, he immediately knows.
The particular example I want is having lots of newspaper headlines intersecting, creating an effect that this event generated a lot of buzz... but I don't know where to find a video example for him?

About the newspaper headlines. I would not call it an effect at first. First it is a storytelling element, with the headlines actually telling something and often carrying the storyline forward - easily anything between three days to several months, plus that you could use it as a prelude for a jump in time of several years. What I'm trying to say is; this effect, as you call it, is a timeline jump in your story.
So in practice it is not an effect first. The way you actually do it is an effect, meaning that you can do it entirely in digital, CG, or real newspapers thrown on a table and filmed as so, a combination of methods, etc. Whatever, you need the headlines in these papers, because your audience is going to read them, or at least have time to grasp the message if not given time to properly read them. Telling a story through newspaper headlines is not a job for effects engineer. You provide the headlines, the story. (A job for your writer(s), not necessarily yourself.)  Then you let your team create a newspaper headlines storytelling section.
Furthermore, say you want to skip filming a court of law section in your story. In between those newspaper headlines you could do very short inserts of video, like the main characters walking up the steps to a courthouse, accompanied with more newspaper headlines, then a clip of grieving after a lost case, and when the media buzz is over, you can continue your film at any distance in time, like 20 years forward if you so wish and the story tells you so. But this was not in your question.
To answer your question - write those headlines and take them to your team, and tell them what you want with the same words that you used to describe your question here. It should be enough for them.

Any set of samples would really have the same problem.  How do you find what you are looking for within them?  If you can draw, story-boarding has traditionally served this purpose.  Part of it could also be to get better editors.  If your editor's are good, they should be able to produce things in a visually interesting way with or without your help and, since you admittedly are not an editor, they should have a better idea of how to do so than you do.
When you do see things you don't like, talk to them about what you don't like about it.  Explain what you don't like about it using their visuals as reference.  Describe to them what you want and ask them what they think of it.  They may have a reason why that wouldn't work well or they may be able to determine exactly what you mean.
A good editor should be able to work with you to identify your meaning even if you don't know exactly what you want.  When you go to a computer repair place, they don't ask you to tell them that you got the "virusAofTheWeek.Beta virus installed in C:\MyVirus\ that you need them to run RemoveMyVirusTool on.  You only tell them, "my computer is acting funny and slow, figure it out".  That's why they are the professional.
If you can't trust them to do this, then it may be that you either need to be a little more trusting of their artistic talents or it may be that you need to find an editor that has the talents and skills necessary to do the job.
Editing also isn't generally a hands off role when you want more direct control.  It is typical for directors to work directly with the editor on key moments or even the entire film/video to ensure their original vision is met.  Even then though, unless the director has editing experience, they should be trusting their editor to make good calls and only offering corrections when it is something they have a real clear picture of in their mind (and even then should be open to feedback from the editor) or feedback on general things like pacing.
Producing video is a collaborative process, work with people who understand and work well with the medium and be willing to trust their work and you will find yourself both less stressed and get a much better final product.

Also, as Esa points out, this isn't an effect you are looking for anyway.  It is a form of motion graphics, which depending on the complexity may be something that the editor won't be able to handle and you may need a motion graphic artist, though a good editor should be able to do a basic form of it and should be able to generate a sense of hype through other devices as well.

Thank you. "Motion Graphics" would be a good term to learn. I agree with you that it should be a collaborative process. In reality though there are a lot of constraints...


text:
Error FFMPEG when convert video to MP4 with baseline presset
I have this command in ffmpeg:
ffmpeg -i '/var/www/sites/default/files/private/videos/original/reel para web en loop_2_2.mp4' -vf 'scale=640:480' -strict experimental -vco
dec 'h264' -vpre 'libx264-baseline' -acodec 'aac' -vprofile 'baseline' -ac '2'
 -y /tmp/1379483589-52393fc5e233e.mp4

And I have the following pressets:
libvpx-1080p50_60.ffpreset  libvpx-720p50_60.ffpreset  libx264-ipod320.ffpreset
libvpx-1080p.ffpreset       libvpx-720p.ffpreset       libx264-ipod640.ffpreset
libvpx-360p.ffpreset        libx264-baseline.ffpreset

And this is the result:
ffmpeg version N-56279-g5295407 Copyright (c) 2000-2013 the FFmpeg developers
  built on Sep 15 2013 03:43:12 with gcc 4.7 (Ubuntu/Linaro 4.7.3-1ubuntu1)
  configuration: --prefix=/usr --enable-gpl --enable-libass --enable-libmp3lame
--enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-
libx264 --enable-nonfree --enable-version3
  libavutil      52. 43.100 / 52. 43.100
  libavcodec     55. 31.101 / 55. 31.101
  libavformat    55. 16.102 / 55. 16.102
  libavdevice    55.  3.100 / 55.  3.100
  libavfilter     3. 84.100 /  3. 84.100
  libswscale      2.  5.100 /  2.  5.100
  libswresample   0. 17.103 /  0. 17.103
  libpostproc    52.  3.100 / 52.  3.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/var/www/sites/default/files/private/vi
deos/original/reel para web en loop_2_2.mp4':
  Metadata:
    major_brand     : mp42
    minor_version   : 0
    compatible_brands: mp42mp41
    creation_time   : 2013-09-12 17:30:22
  Duration: 00:00:39.32, start: 0.000000, bitrate: 3190 kb/s
    Stream #0:0(eng): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv), 720x4
80 [SAR 40:33 DAR 20:11], 2991 kb/s, 29.97 fps, 29.97 tbr, 29970 tbn, 59.94 tbc
(default)
    Metadata:
      creation_time   : 2013-09-12 17:30:22
      handler_name    : Mainconcept MP4 Video Media Handler
    Stream #0:1(eng): Audio: aac (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 18
9 kb/s (default)
    Metadata:
      creation_time   : 2013-09-12 17:30:22
      handler_name    : Mainconcept MP4 Sound Media Handler
[NULL @ 0xab9d980] [Eval @ 0xbfd87b9c] Undefined constant or missing '(' in 'wpr
ed'
[NULL @ 0xab9d980] Unable to parse option value "wpred-dct8x8"
[NULL @ 0xab9d980] Error setting option flags2 to value -wpred-dct8x8.
Output #0, mp4, to '/tmp/1379483589-52393fc5e233e.mp4':
  Metadata:
    major_brand     : mp42
    minor_version   : 0
    compatible_brands: mp42mp41
    Stream #0:0(eng): Video: h264, yuv420p, 640x480 [SAR 15:11 DAR 20:11], q=-1-
-1, 90k tbn, 29.97 tbc (default)
    Metadata:
      creation_time   : 2013-09-12 17:30:22
      handler_name    : Mainconcept MP4 Video Media Handler
    Stream #0:1(eng): Audio: aac, 48000 Hz, stereo, fltp, 128 kb/s (default)
    Metadata:
      creation_time   : 2013-09-12 17:30:22
      handler_name    : Mainconcept MP4 Sound Media Handler
Stream mapping:
  Stream #0:0 -> #0:0 (h264 -> libx264)
  Stream #0:1 -> #0:1 (aac -> aac)
Error while opening encoder for output stream #0:0 - maybe incorrect parameters
such as bit_rate, rate, width or height

What is the problem in my command? I have baseline profile in ffmpeg. Or I need do one more step?
I need that this file playing in iPhone in MP4. Because I use JW Player.

This looks to me like an actual issue with the scripts in the preset vs your build of FFMpeg.  It appears that the syntax of options being passed to the encoder are incorrect (particularly something related to "wpred" and a missing parens) and since they are not specified in your command line, I can only assume it is the preset that is the problem.  I would suggest trying either a different version, a different build or a different source for your copy of FFMPEG and see if you have better luck.

So, I need download other version of FFMPEG and rebuild.

@Dvex - that's my best guess given the error.  I could be wrong though.  I don't have any specific experience with FFMPEG, but I'm a software developer in general and the error seems to indicate that the profile being used doesn't match with the build or is simply corrupt.

Remove -vpre 'libx264-baseline'. This preset should not be included with your ffmpeg build and is designed for older builds; therefore resulting in usage of unsupported, old options. I am guessing you copied the old preset file from somewhere are tried to get a newer ffmpeg to use it.
Using -vprofile 'baseline' should suffice.
See the FFmpeg and x264 Encoding Guide and FFmpeg and AAC Encoding Guide for more info.


text:
How to batch process hundreds of videos?
I have hundreds of videos in storage I need to distribute online.  I'd like to do the following for each clip:

Add a pre-roll video
Process the audio (audio leveling, generic hiss/noise reduction for speaking (no music or other sound))
Add a title overlay at the beginning and end (could be same for all videos, but would like to pull from a spreadsheet to individualize each video if easily accomplished)
Convert video from AVCHD 1080p24 to format(s) suitable for Youtube and Vimeo with as little loss of quality as possible.

While static overlays are fine, it would be nice if things were animatable to add a bit more interest to the final product.
I'm a programmer, so I'm fine with scripting.  My primary video system is an older windows 7 64 bit machine with a quad-core i7 and 16GB RAM.  I'd be fine turning it into a linux machine temporarily if there are better workflows in that environment. I also have a quad core i7 OS X laptop with 16GB memory, but the disk is slower. There's no particular deadline, so if chewing through these videos slowly can be done cheaply, then that's better than paying for quick conversion, but speed would be nice, particularly if I can task multiple machines to the conversion easily on my network.
I'd prefer not to spend more money, but if there's software that can help me out significantly then buying the correct software might be acceptable.
How do I accomplish this task without spending months individually editing each video once or twice a day?

I'm not a programmer but I think this is all possible using ffmpeg and sox. Here are examples for a pre-roll video, audio noise reduction, text overlay and convert AVCHD

As I'm not familiar with the CLI very well I have no clue on how to string that all together into a nice script, so won't post it as an answer.

@BartArondson I think that's an excellent answer, though, and gets me enough information to get started.  Add it as an answer so I can accept it, and thanks!

I've been looking in to this as well.  I have been working on a system using some .Net libraries to build a tool around but I can't recall the name of it currently.  It was free for non-commercial use (non-commercial meaning you aren't selling the software, not that you aren't making videos for commercial purposes).  I will post later with the name of the product as it seemed relatively easy to use.

You can achieve all your goals using ffmpeg and sox, these are command line tools for video and audio processing respectively.
I can not provide you with a ready to roll solution, but here are examples for a pre-roll video, audio noise reduction, text overlay and conversion from AVCHD.

Quite an expensive solution: Sony Vegas Pro + Transcoder plugin can do it :)

Draft that we bundle with Deadline was built to do this sort of thing. Full disclosure: I work for the company that makes this.
Docs for Draft's fancy features.
http://docs.thinkboxsoftware.com/products/draft/1.5/Documentation/#basic-operations
Minimum cost is about $200 US at the moment for one machine, but you get a huge amount of process automation here.


text:
Which sequence settings in Adobe Premiere for a YouTube video
I have a series of photos 3840x2880 which I want to crop to make a 1080 timelapse video to be uploaded to YouTube.
Which sequence setting in Adobe Premiere CS6 I should use for YouTube videos?

There are presets for Youtube specifically already in Adobe Media Encoder.  I would suggest using one of them.  You can also find the technical recommendations from Youtube on how to encode the videos here, however I believe the presets already conform to these recommendations.

Isn't Media Encoder used to "recode" existing videos? What I was asking is a step before, what sequence settings to choose before I even import my time lapse photos.

@6bytes - there are two possible questions here, the one I interpreted you asking is how do you export a sequence you have in Premiere for Youtube.  You do that through using Adobe Media Encoder and the Youtube preset (you choose external rendering in Premiere and it will automatically add it to Adobe Media Encoder for you or you can add the project to a Media Encoder queue from Media Encoder itself as well.)  Media encoder can actually be used as an external batch render engine for most of the Adobe software.  I normally run my renders in encoder to batch them up and use nested projects.

The other question would be how do you import an image sequence as a source clip in Premiere and this has nothing to do with the final desired output.  You simply make sure that you have an incrementing value on the end of a common file name and then do an import of the images and be sure to choose the Image Sequence checkbox so that it brings it in as a video source clip.


text:
Can two GoPro Hero3 cameras be made to capture the same frame from the same spot?
I just bought a Hero3 Silver camera, intending to check it out a bit before getting a second one for 3D. Checked it out, and apart from a malfunctioning time-lapse, liked it, made my second camera a Hero3 Black. These two cameras don't capture anywhere near the same frame, and so appear to be useless as a 3D pair. So I bought another Hero3 Black, expecting the two Blacks to capture the same frame. They don't.
Mounted precisely in the same spot, each camera captures a different area. The two Blacks also differ in rotation.
http://solsifa.com/hero3/
Is this normal behavior for these cameras? In fact, is this expected behavior for cameras in general?
Can two Hero3 cameras be made to capture the same frame from the same spot? Say, by adjusting the lens, the CCD chip or something?
Thanks in advance.
Gunnar Jonsson.

GoPro Hero's are frequently used in the kind of capacity you describe.  It is possible you got some defective units (as certainly the time lapse stuff for the silver is a bad unit), however much of the problems appear to be user error rather than camera problems.
In your overlay shots, the frame appears to be consistent, they just aren't pointed in the same direction.  Keep in mind that a very small amount of variation in positioning will result in a drastically shifted image.  If you are just setting the camera on a table, picking it up and putting another one down in the same place, I would expect results like you are getting.
To really do what you are trying, you need to get a mount for the purpose that will hold the GoPro's in proper alignment.  With many cameras, this type of rig is a custom job, but for the GoPro, things like this are done so often that you can actually buy pre-made rigs for them for things like 3D shooting, 360 degree shots (or even video), time lapse tracking rigs and other forms of multi-shot rigs.
If you get one of these mounts and are still having problems, contact GoPro about the problem because they should be consistent.

When I wrote "Mounted precisely in the same spot", that's what I meant. Custom-made mount for this purpose. I'll take your suggestions into account.

@GunnarJonsson - yeah, I'd contact GoPro then.  Based on how frequently they are used for this purpose, this sounds like defective units.


text:
Update keyframe animations only every third frame in After Effects
I am new to After Effects and I have the following problem with an animation of mine:
I have a walk cycle drawn for 8 frames per second.
The composition has 24 frames per second, so each frame of the animation is shown for three frames. The background moves using keyframe animation.
But now the background moves every frame whereas the animation only moves every third frame, which looks odd as the feet seem to slip. If I change the frame rate to 8fps, it looks fine.
So is it somehow possible to change the movement of the background so that the position is only updated every third frame?
I would like to avoid changing the frame rate of the whole composition to 8fps, as then other parts of the animation become less smooth.

I don't know if there is an easy way to do it directly.  You could do some modular math in a script for the keyframe positions, but that's kind of complicated and non-user friendly.  An alternate approach would be to do an additional nested composition.
Make an animation composition for your character that is at 8 FPS, perhaps bring in the main composition as a backplate while putting it together, then remove the backplate and import the animation composition at 24fps as a stationary composition.

I already tried your second approach. But unfortunately the composition (or at least the animated properties) become 24fps as soon as they are imported into a 24fps composition. Although I am not sure, what a 'stationary' composition is, exactly.

But since I am from a programming background I found you first idea quite appealing and was able apply it to my problem. I used the following expression: transform.position = position.valueAtTime(Math.ceil(-2/3 + time*8)/8)

@sietschie - I just meant that you include the composition as a nested composition and don't animate it any.  Interesting that it automatically updated the frame rate within when you tried that.  I think there might be a setting to prevent that, but I don't recall exactly.  (I don't have to deal with the mismatch problem often.)  Glad the scripting worked for you though.


text:
Scrolling the panel in After Effects
I'm on windows using After Effects CS6.
I'm new to this software and am having a problem scrolling the window vertically or horizontally, Where is the scroll bar?
Alternatively I'm trying to scroll using the mouse wheel, but this seems to be zooming in and out. I read that I can hold the Alt or Ctrl button while moving the wheel, but that doesn't make any difference.
I just want to scroll the panel up and down so I can see what I'm doing.

After tearing my hair out I found the "hand cursor", now I can drag the panel around however I want it :)

Glad you found it.  Thanks for posting what you found.  Also, welcome to AVP.

wow, thanks a lot

Also - try holding the space bar down.. It temporarily turns your cursor into a hand grabber.  Very "handy" (sorry)


text:
After effects: masking not working in select compositions
Whenever I try to mask a clip or multiple clips in my main composition, the mask has no effect, neither does inverting the mask or any of the other mask modes provided. The same thing happens when I pre-compose a clip from my main composition. Masks do still work on adjustment layers though.
However if i take the same clip from my clips in the project section and create a new composition with it, masking seems to work fine.
I don't know if I have disabled a setting in my main composition that would have caused this (I can't find any difference between my main and any new compositions), and it seems that nobody else has had this problem or that the answer is simplistic.
Let me know if you need anymore information. Any help will be greatly appreciated.
Regards

Clips were originally twixtored, which prevented my masks from showing as twixtor has its own masks and splines.
Resolved this by first twixtoring my clips, pre-compsing the clip and then masking the composition

Most likely you have effects on those layers that are being applied and messing up your masks, anything from the distort effects will do this, and others as well...you can wither pre-comp your layers or use layer masks

I believe this is the intended function. Masks are not meant for the main (i.e., background) clip. They are only meant for clips that will overlay others. Otherwise, what would display behind the masked-out areas?

I don't think he is talking about an issue with the bottom layer, but rather his main composition.  Compositions are like timelines in After Effects and so his main Composition would simply be the Composition which he is nesting sub-compositions within.  It sounds like he is having an issue where the mask doesn't work in his main composition but if he moves the assets to a sub-composition, the mask works fine.


text:
Forcing kdenlive to adapt its profile to the video clip
kdenlive starts with a profile for instance 1080*720/etc.
Then I import a video clip.
How to tell kdenlive to modify its profile to match the video clip?
Modifying the profile manually by copy/pasting each of the clip's properties is very time-consuming and error-prone, I am sure there is a better way to do this.

Curious... recent versions of KDEnlive practically push this option into your face once you add a clip with properties different from the project.
If the option got disabled in your setup you can enable it again by going to Settings -> Configure KDEnlive -> Misc (selected by default) -> [ ] check if first added clip matches project profile
I am using this option in version 0.9.6 on Debian, but I've seen this behaviour in 0.9.4 and probably older versions as well.
Also if you got used at some point to dismissing this funny question window you get immediately when adding a clip, try to control the urge this time - the question is whether KDEnlive should adjust the project properties, which is what you want ;-)
(don't be mad at me if you think this last part is stupid, I've done user support occasionally and I have seen people do this;-)

any news on this? KDEnLive 15.12.3, I still have to create a profile identical to the clip, even with such option enabled :(

Works flawlessy in 17.08.2

Select a clip, then use the menu option Project -> Adjust Project Profile to Current Clip.


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Sync audio and video, equipment?
I need some help or tips in the area of video and audio sync. Think a music videoclip, where the audio is recorded independently to create a master audio track and then the video will follow along. Not interested at all in the audio recorded with the videocamera.
I'm experienced with the audio part, but have done only one video project of this nature with iMovie (absolute noob and not willing to invest much in video editing software at the moment).  While editing, it was an absolute pain to get everything in sync, lips motion with lyrics, ... I had to do it by hand drag and dropping frames around the audio track. Waste of time.
I was wondering if there's anything I can do while recording either the audio or the video that would easy this process. I do have semi-pro audio equipment with timing signals like SMPTE and things like that but I've never used them, not sure if they would be of any help for this.
Thanks!

Haha! In movies about movies you always see this clap in the beginning of a shot. The one where the take number and everything is written on with chalk. And they hold it in front of the cam and make one loud clapping noise with it.
Well, if you have ever wondered what this ritual is for, congrats! You have found the problem to the solution ;-))
You get a video frame on which you see the clap closing and at the same time you can see the noise level peeking in the audio recording.
The poor mans version of this is to tell one of your actors to do the clap with her hands.

Oh, and don't feel bad if you didn't now. They never tell you this in the documentaries. I didn't find this out either, until I started hanging out with film crews.

There is a very expensive piece of highly specialized gear that can easily fix this problem....
It's called a boom box. :)  The secret to doing any kind of sync like this is to finish either the audio or video first and then play one while you work on the other.  You can insert a quick beep just before the beginning so that it can be easily matched in post.  This is the point of that clapper thing they use at the beginning of film clips.
Simply lip sync to the audio that is playing and/or dub over the mouth movements using a script (depending if you are doing video after audio or audio after video.
Cheaper audio gear will sometime have problems with bad timing that will cause drift, but decent quality semi-pro or pro gear should hold sync well even with hour or more run times.  If you do find that drift is a problem, try using a clapper or beep before the beginning and the end and then do a speed correction, which should work well as long as you don't have dropped frames.

Thanks AJ. Yes, I work with the audio already finished and in a single track, then start cut and pasting my pieces of video one after the other, adding transitions, etc... When the scene is short, then doing this manually is not that bad, since there's not time for the audio and video to go very out of sync, but for longer scenes, it's incredibly hard to start the video scene at the precise millisecond so that after 30 seconds or more you start noticing a slight out of sync in the lip movement. Where can I read more about the technique you describe? Thanks again!

@palako If your audio is drifting out of sync that rapidly, something is seriously wrong in your process.  Even fairly poor, old gear should only drift noticeably after a few minutes.  Have you tried aligning the audio and video without editing and then using that as a nested sequence?  Do you still end up with problems in sync even if you use a constant rolling clip with the audio rolling constantly as well?  Are you sure you are not getting dropped frames?  What kind of gear are you using for the audio and video?

By the way, if you want to be able to search for more details as well, the term for what we are discussing is dubbing because the effort is to sync a performance to an existing media.

Thanks, I'll find more info on dubbing. My sync problem is very simple and the root very obvious, I have a video track and an audio track, I manually try to get them to start at the same moment, but this is a drag and drop action on a very intuitive, yet non sophisticated interface, remember I'm using iMovie, so even if both sources run at their right pace with no gear or software problems, if they didn't start exactly when they should, they get out of sync.

@palako - that isn't correct.  If you start off with, say a 30ms offset, that offset should not grow.  The video and audio should run at the same rate and the offset should remain a constant 30ms throughout the entire video.  If the amount of offset is changing (which it seemed like you were indicating is the case), then you have a much more serious problem.

I guess you're right, that makes sense. It's probably that is harder to notice that I'm not starting it at the exact moment when the scene is short enough. Thanks for your tips.


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Origin of "desktop capture engine"
I'm trying to locate a desktop capture driver.
I am using Flash Media Encoder 3.2 and had a device listed as "desktop capture engine" in my list of devices. Allowed me to stream my desktop.
I had no idea where it came from so I tried to uninstall some programs to see which one "removed" it. Bright idea, I Know!
So after removing RealVNC and Super! from my computer, it's gone, but re-installing those programs doesn't re-add the device. I'm wondering if I had a different version of RealVNC installed. I don't remember downloading from their website before.
Anyone know what the origin of this driver might be?

super now have more virus/spiwares and trash, uninstall it.. if can the damage in the windows is terrible..
i lost more time romoving, it from windows init, services, etc.

I have installed SUPER today, and Desktop Capture Engine has appeared on my computer.

I have just installed this thing and after I declined all the "useless ads" I got like over 9000 viruses with this app. I am already dealing with them for an hour and actually winning. But gosh... Like really? This type of program makes this to my computer?


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Is there a thing that can hold the subject in front of the camera, locked, not moving while shooting video?
I want to shoot a video for my iPhone app demo. My idea is shoot a phone running the app, and the iPhone is relatively still in the video, while I could move the camera around, so the background changes, but not the phone. Is there something available to do this? I would imagine something like an extension arm, one side holds the camera, and the other side holds my phone. I don't know if this thing exists nor not. Please help, thanks! (What I have now is a DSLR and a tripod)

Yes, what you are talking about falls in the realm of rigging.  There are lots and lots of rigging products available, but most of the specialty built rigs are going to be very expensive for your needs (hundreds to probably over a thousand USD).  If you aren't turned off by the price, I suggest looking at rigs in a web store like B&H to find something that will suit your needs and allow attaching an extension and the phone mount.
You might be better off to do something yourself to save money.  You should be able to buy a basic mount plate that you could bolt to a pipe and then on the other end attach a device holder for the phone.  I'd probably try and do it with something like a Trident case that will look like a nice case on the phone while allowing you to attach the mount to the back of the case securely.  It will still probably run you a couple hundred USD though, even making it yourself.  (Trident cases and the stand for it alone will run you $70 or so.)


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Video editor suggestion
I'm new here.
I'm looking for a easy-to-use video editor, like windows movie maker but with a couple of more tools like: adding videos over a video and adding two or more lines of text simultaneously appearing with different effects. I'm using Windows 7 and the software must be free. Thanks for your suggestions!

possible duplicate of Good open source Video Editors?

Start here: 10 free video editors mirror.
Keep in mind that free video editors are very simple and do not have many effects.
I recommend you to buy inexpensive video editing software, like Sony Movie Studio or Cyberlink PowerDirector. Take a look at this list of consumer video editors mirror.


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Video Live Embed from external websites
I want to make a website where visitors can view webcams from the world. I want to make categories per countries, a map etc. The problem is that 90% of webcams i find on internet are .mjpg or .cgi. So, i've made a code that make this mjpg working in IE 8,9 etc. I can't put links to these websites that contains these webcams because on their sites, these streams doesn't work in IE. So I need to load the image in HTML:  from their website.
Is legally to load the stream form these external sites? Must I put a link above the picture to their website? What can I do to be legally? I want to make this site without external links for viewing of the stream.
If this question is not appropriate for asking here, please leave a comment, and I will delete it (please tell me where can I ask this question).
Thank you in advance!

This questions appears to be more about web development and etiquette than audio/video production as you are simply reusing an existing stream rather than making your own.

What you are referring to is called hot linking, and while it may or may not technically be a violation of their copyright or terms of use (check their website for details) it is still generally considered a poor practice since you are effectively utilizing their bandwidth without mentioning that it is their bandwidth.
Your best bet is to contact the operators of those cameras and ask them what they think.

Thank you. I want to use hot linking. May I put in the description: "Source: http....website" ? (to be legal)

@ITChristian - it depends entirely on the terms of service (if any) on the site in question.  They are making the content publicly available, but if their terms of service say they don't allow direct linking, then you would be doing the digital equivalent of trespassing by using their resources in a way they don't allow.  The best bet is to check with them and let them know what you want to do.


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How to make this kind of animated video?
I just want to make videos like this one:

But I can't imagine how to do them. I mean, what kind of software is he using?

This is called a "write on" effect and is typically accomplished with either a 2d animation package such as Adobe Flash or with a motion graphics software package such as Adobe After Effects or Apple Motion.
It generally involves building the imagery as vector graphics.  Any lines that will be animated are generally drawn as paths that can be "written on" by starting at the beginning of the path and drawing the line until it reaches the end of the path.
It can also be accomplished using motion recording and a digitizer tablet which will allow the writing to be done in real time and recorded, it can then be accelerated or decelerated as needed, or the paths created and timings can be tweaked to smooth things out using typical keyframe animation.


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Record VGA/DVI with timecode
I'd like to record presentations and lectures and then edit them after the fact. I'll use one or more camera feeds and a timecode source (either a camcorder or external source). To record the screen, I was thinking of using something like the Blackmagic Hyperdeck Shuttle, but I'm not stuck on this device.
The Shuttle can record HDMI sources (great--I can record DVI or convert VGA to HDMI). However, it can only record timecode from SDI. I could convert HDMI to SDI, but then where does the timecode come from? Is there any way I can inject the timecode into my SDI stream?
Any other totally different solutions?

If cost isn't an object, I believe the higher end rack mount HyperDeck accepts an external timecode (ref in), but it's also quite a bit more expensive ($1000).

Cost is an object, but chaining HDMI to SDI converters and timecode inserters to the HyperDeck Shuttle would quickly move the system price from $340 towards $1000 as well--Thanks!

@watkipet - yeah, working with unified time code usually is expensive.  Black Magic Design at least makes it a little cheaper.


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Record Screencast of Remote Presenter
For some time now I've been looking for screencast software that can record someone presenting on another computer. The application is for a commercial screencast recording company that comes in and records screencasts of lectures, product demos, and keynotes for other companies.
The problem I run into is that all the screencast software I've seen records only the local screen. That doesn't work--we can't load screencast software on the presenter's computer. What we've used so far is Wirecast and Desktop Presenter. Desktop Presenter goes on the presenter's computer, and Wirecast goes on our recording cart computer. This works, but it produces videos that are difficult to edit (we use QuickTime Pro 7 to edit without re-compressing). If we had something like ScreenFlow that also had remote recording (i.e. Desktop Presenter)--that would be perfect. Anyone know of a product like this? If no product like I've described exists, can you think of another creative solution? It would be ideal if the solution can track and zoom in on mouse movement like many screencast products do (i.e. Camtasia Studio and ScreenFlow).

You have two options, one, install software on the presenter's system that can encode and send a video feed to another system.  This is in-effect going to be a screen casting application, even if the feed is only forwarded to another system to be packaged.
The other option is to actually capture the raw output from the presenter's system through a frame grabber or video interface of some type.  This is the least invasive way, but then have no idea about cursor position or the like.
There is no solution that can connect to another computer and grab whatever is on their screen without putting software on that computer.  You can however do something minimally invasive like putting a VNC server that can run from a USB stick without installing and then connect to that VNC server and run the screen capture off the VNC client on a system you control.

I guess installing some software is OK. I install Desktop Presenter right now, and that usually works out OK. I would be OK with the VNC option too, but mouse tracking still wouldn't work, would it?

@watkipet - probably not.  Your best bet is probably to just use a screencasting application that works for the initial needs in the background and then have it send to a system that can actually do the recording, but I'm not sure what would do that specifically.  I normally run the presentation side of things and just do video captures of the output we send to the projector or even run the on screen graphics from my machine and just watch when they advance on a preview monitor.  (So when they hit the next button, I do the same on mine, but this only works if they aren't pointing to things.)


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best software for multicam video production
We have records from 30 cameras (couple TBs of video files), which were started almost simultaneously, part of them were action cameras (so no timecode here, and there are gaps because of battery replacement), other part were usual hd cameras with time codes embeded to video files.
All video is 1080p25.
We need to sync all videos together, and then render all 30 sequences after color correction and cutting.I have tried adobe premiere cc, but is was real pain, especially rendering with crushes and other glitches.
Is there any alternative for Premiere?
We have quite recent workstations running windows 7 with consumer video cards (both ati 7970 and nvidia 680 are available), so it will be great if software can do distributed rendering and use gpu. We also have couple of 2 year mac pro, so osx only software can also be of use.

What do you mean by crushes and other glitches.  Premiere should be pretty stable and reliable if your hardware is.  Is it a) legit and b) fully patched (the OS, Premiere and hardware drivers)?

I believe hardware is ok, other 3d applications, such as cinema4d are running fine, there are about 5 five computers that we have tried and all give similar results with media encoder: it can trow cpp exception, it cat just stale on some file and do nothing, it can abort encoding with unknown error
last time i tried i have used youtube 480p preset. Also encoding is not very fast, about an hour for 15 minutes of video on i7 3770 with 16gb of ram and gf680.

something is wrong then, it should not take more than 30 minutes tops for doing that encode in 1080p quality.  480 should be even faster.  I'm running a first gen I7 with a Radeon 6970 and 12gb of RAM and get better performance.  Something is either wrong with either your drivers, your installation media or your assets.

I have found the problem, sequences were 4 hours long and i needed only 15 minutes, so I have selected all encoding tasks in AME and changed not only encoding options, but time ranges in format dialog, encoding options were applied to all encoding tasks, but time ranges werent!

No matter what software you use, you might want to invest in server grade hardware.  Used servers with good specs can be had from ebay for under $500

Premiere is your best option unless you plan on spending a boatload (thousands and thousands) on an Avid system.  I'd suggest working on smaller sets of cameras at a time and then working off the combined feeds.  You can use multicamera editing mode with several cameras at a time, make the best choices out of those and then run each of those sequences in to another multicamera sequence to further resolve them.
The process is going to kind of suck no matter what system you do it on because it is a boatload of synchronous footage to go through.

Lightworks just became another professional option for multicam editing in version 11.5.
And there is a free version.

You could always try PluralEyes by red giant as long as there is some sound it should work, I don't know what your footage is so its a bit hard to say.
PP should work fine same for FCPX.
I normally put them all in my timelines in FCPX export to Pluraleyes do the sync then back into FCPX, baring in mind most of the time mine is between 2-4 cameras tho

Why use PluralEyes?  You know you can sync multicam clips using audio inside FCPX now, right?  I'm asking because I'm seriously curious about what benefits PluralEyes offers.  I tried it once, but it didn't seem to be much better.

I found that when using PP or FCPX it was not syncing my footage correctly, this could be down to to much varied footage or audio not being the best on one cam (a bit louder) but when using PE it worked first time

I know this is "consumer" but power director on a windows platform has multicam with audio sync. 4 cameras is pretty easy with a multicam plug in they have.
you could do up to 100 video tracks syncing by audio. I am sure it would take a super computer to sync though. I have a fairly powerful xeon based system, but the app is I/o bound when running rather than memory or CPU bound. I am not sure, but i blame this on "consumer" level programming. The program was just not architected for "pro level work".

You can also try Sony Vegas Pro (only Windows). It has good multicam features

How about ScreenFlow from http://www.telestream.net/screenflow/overview.htm?
I'm using it right now, but don't know you like it or not or any other software that has good features than this.

This is too generic of a question. You have to specifically ask what task are you trying with this software that you need help with. As opposed to what are the good features of this software.

eLouai - ptoukhmer's post is not a question. It's an answer (sort of)


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What options are there for hardware encoding/decoding?
For the last 24 hours I've been waiting for some files from a Sony camera (about 60Gb) to convert to MP4. I'm thinking there must be some other way to speed this up. I'd much rather go for a purpose-built piece of hardware rather than trust CUDA or ATI as these options have failed miserably (I have both ATI and NVIDIA cards and it seems the software simply ignores them).
So, what are my options for hardware transcoding?

While this is borderline a product recommendation question, there is an entire class of hardware encoders that support h.264.  The cheapest ones I know of are made by Black Magic Design.  Matrox also makes some pretty affordable ones.  Be aware you are still talking about a $200 - $500+ device for doing the real time encoding though.

But in this case, presumably, the software used to encode video must support the device, right? Or is it a driver thing?

@DmitriNesteruk - depends on the device.  Often they either have their own software for using the encoder or will provide support that popular encoders can hook in to.

you mention realtime encoding, but what I actually need is beyond realtime, e.g., converting an existing uncompressed AVI to MP4... instantly, if possible.

@dmitri acceleration cards will go faster than real time these days but it still takes time. You are primarily limited by how much processing you throw at it.

I'm sure there are dedicated MP4 encoders out there, maybe someone else has better info.
But I've had good results using AVC Ultimate, which takes advantage of CUDA on an NVIDIA card to speed up MP4 processing, to about double the rate I get without it. There's a free version, but I can't remember if the CUDA option is available in that -- I've used the paid version for quite a while.

There are many hardware options including Intel media SDK, FPGA options, nvidi, ASIC solutions, elgato, etc. But for my money, I prefer quality. The software solutions, especially x264, perform WAY (WAY) better as measured by visual quality by file size ratio. As for Quality per watt in terms of encoding, you cant beat a good ASIC.

Any COTS ASIC/FPGA solutions out there?


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After Effects CC slant effect crops artwork
I'm a newbie to AE so there's probably a simple answer to this. So I've imported some art from illustrator and dropped in on the stage. I then Create shapes from vector layer. Then I apply the effect CC Slant under the Distort menu under Effects and give the slant a value of 50.

Looking good. Until I move it to the edge of the stage and then the artwork gets cropped. Notice how only the "mple" of "Example" are visible:

Even after rendering the movie (with the position changing from center stage to left stage while slanted), the problem persists. I have tried re-importing my artwork, and applying the slant effect while the artwork is in different positions on the stage to no avail. I've also tried other effects like the warp effect, and the same thing happens.
Is there a way to keep the artwork from getting cropped on the edge of the stage?

This is very odd and not expected behavior.  I have nothing in the way of answers for you but wanted to comment that it isn't just you.  This is bizarre.

@AJHenderson thanks, maybe I should post the problem in an Adobe CC forum...

I don't think so, bc I created shapes from the layer. I can tell you for sure it's not part of a composition.. I even tried scaling it down, applying the effect and then pre-composing it, and scaling up the composition, to no avail.

I would offer to let you post the project and I'd take a look, but unfortunately, I don't have CC because I refuse to allow my access to my work to be ransomed to me.  I updated my answer below with an idea to try working around it though.

@AJHenderson yea the subscription pay model is super annoying. Still on a free trial right now, but I feel your pain. I understand why they did it, but it has some major downfalls for the user.

Depending on how you imported it, it is possible that it ended up nested as a nested composition or smart object.  If you applied the effect to the outer object but then dragged it within the inner object, you could end up dragging it off the edge of the outer object which would produce the result you are experiencing.
Effectively, you would have an outer object that is tilted and an inner object that is going off the edge of the outer.  Thus, the outer object displays only the half of the object you see and then the skew gets applied (which makes the otherwise vertical clipping to be angled.)
That's the only thing that occurs to me as a possible cause.
Even if that isn't it, a work around might be to put the original graphic in a composition and then apply the effect to the composition instead and then move the composition as you need.  This would probably work around whatever issue you are having here.

The part of your answer that worked was creating a composition from the art and applying CC Slant to the composition. Thanks!

Just pre-compose the layer with the CC Slant effect, and make this new comp a little wider than Your main comp. The crop will still happen but You won´t see in Your main comp, because it´s out of frame.

Try using the Transform effect (effects>distort>transform IIRC), and use the skew setting to achieve the same thing. It always works reliably for me.


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Canon XF100 live stream -- additional hardware needed
Question: How to get the XF100 to live-feed into a laptop for streaming?
Details:
I currently have a Canon XF100 HD video camera, and I need to use it for live streaming of some upcoming events.  I also need to do a HD stream (opposed to SD).  The outputs on the camera are HDMI, YPbPr, and SD RCA plugs.
I would think HDMI or YPbPr with red/white audio would be best, however the part I need to know is, how do I get this into a laptop?  A desktop is not an option in this case.   We do have some laptops around, but we also might be able to get a new laptop if needed.

You need a capture card.  If you have either USB3 or Thunderbolt, then you can use something like the Black Magic Intensity or Matrox MXO2.  You could also consider a stand alone device that is capable of handling the streaming for you directly, such as the Matrox Monarch or similar devices that don't have to rely on the computer's processing to send the stream.

going the black magic intensity route.

For getting this to work with the blackmagic intensity, and OBS for streaming, I had to go into control panel and then into the blackmagic control panel, set it to hdmi, and use 1080i 59.97. After that was set, I opened OBS and for my source I set it to decklink, and then clicked the config for that, and set it to 1080i 59.97. then finally on the page where I selected decklink, I turned on custom resolution and set it to 1920x1080 with a 29.97 frame rate.
It's extremely touchy on the settings, everything has to match everywhere, also downgraded drivers from 9.8 to 9.7


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Why do some camcorders record in 1080i?
Why do some camcorders record in 1080i? Does it have any technical or visual advantages over 1080p?
Let's suppose that all media players and TVs which can handle 1080i can also handle 1080p. Is there still an advantage of 1080i?

It uses a lower data rate (within the TV, not for the actual signal) and is cheaper to produce.  That is all.  The only difference is that if you are going to view it on a 1080i display, then shooting in 1080i would look slightly smoother since half the information updates every half a frame rather than updating the whole thing at once, but 1080p is preferable pretty much hands down on a 1080p display.
Interlacing just means that the upper and then lower fields update alternately.  It's less difficult to fake interlacing than it is to deinterlace, but you still get some artifacts displaying a progressive scan image on an interlaced display because of how things update.

There are no interlaced displays anymore, though.

@leftaroundabout - maybe no new ones, but there are still 1080i displays that don't support 1080p hanging around.  I have one in my bedroom.

Don't forget that many broadcast stations (air waves vs. cable or satellite) broadcast in 1080i.

@AJHenderson - Why is the 'lower data rate' claim?

@Izhaki - within the display it is a lower data rate as only half the screen has to be refreshed at a time.  Each field is only half the information, and while there is still twice as many fields as frames, each field only has to update 30 times a second.  Thus, the TV only has to have half the data rate for each field (but the total between the fields is the same).  This matters for loading in to the frame buffers that control the display.

Oh... OK.... The last sentence gives the real explanation. One can easily misinterpret your answer to think that interlaced has altogether lower data rate than progressive. As you mentioned, both involve the same amount of data (only with interlaced a frame is split into 2 fields).

@Izhaki - agreed, I updated the answer to make it more clear.


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Color autocorrected on my Canon G10 in the middle of filming, any tips for editing in post?
I was filming a music recital when the color autocorrected on my canon g10. I am new at all of this, but I recently bought final cut pro x and I was wondering if anybody could point me in the right direction for correcting this. There is a 5 second period in the video where the colors shift from dark to light, how would I go about smoothing this out in post?
Thanks

Not easily.  You would need to apply a color correction to try to replicate the change.  If you can use the color correction to get the beginning and end pretty close, you can then use keyframes to have it blend between them and hopefully overcome the adjustment, but results are still probably going to be so-so and it isn't trivial to get even a mediocre fix.

Thanks for the reply. I figured this wouldn't happen without some sort of keyframe kind of thing. I guess in the future if I have it set to auto, I will make sure it is completely adjusted to the room (it's too bad, it must have been when the hall lights dimmed or something)

@AustinSlominski - yeah, in general with video you want to try to avoid things like auto-exposure and auto-white balance.  I've seen them ruin far too many shots.


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How to make a multi-audio video into several video files with one audio track each?
Suppose that we have one video file in.mkv, which has two audio tracks, what is the most direct way to remux it into two separate mkv files with just one audio track?
Two streams is an example, the technique should work with 100 audio streams.

There are several ways to do that. The simplest, but not the best would be to run some sort of remuxing twice, each time taking just a single audio track. But since there is no re-encoding the speed will go down since the computer is forced to read the whole file twice (or more times if you have more audio tracks).
To accomplish the task with a single read using libav (ffmpeg will probably be the same):
avconv -i in.mkv -map 0:0 -map 0:1 -c:a copy -c:v copy out1.mkv -map 0:0 -map 0:2 -c:a copy -c:v copy out2.mkv

It is probably also possible to do that with gstreamer.