text:
How to precisely synchronise an audio and video track from separate devices?
Yesterday I recorded a full day event with a Panasonic HC-V700 Full HD Camcorder and I also captured the audio with a Zoom H4n Handy Recorder using the audio feed provided by the venue.  At the start I captured a "clap" in front of the venue microphone and the video camero to synchronise the two sources.
How do I precisely synchronise the audio and the video tracks using the "clap"?

I am using Adobe Premiere CC.
I have got the two tracks almost synched.
My Adobe Premiere skill level is basic.
I can't work out where the nudge tool is to move the audio track via the keyboard.

First off, if you have audio with your video (that you want to replace with your high-quality audio recording), then step #1 is to nudge the Zoom audio track to line up the impulse of the clap with the corresponding impulse of the scratch audio from the video file.  To do that, you need to change the Timecode Display Format to Audio Samples.  Once you do that, audio can be nudged a sample at a time, which makes it possible to get two audio files to agree, rather than a frame at a time, which makes it impossible.
To learn the keyboard shortcuts (which include the Nudge commands), print and study this page from the Adobe manual.  TL;DR: Nudge right is Alt+Right on Windows and Cmd+Right on OSX.  To nudge five frames at a time, add a Shift.  To nudge left instead of right, change from the Right Arrow to the Left Arrow.
Once you have your high quality audio aligned with your principal video, it's time to sync all the rest of your video with your principal video.  If you shoot at 24fps and capture audio at 48kHz, a single frame of video is 2000 audio samples, which is a lot of samples to sort through looking for the start of the clap!  But don't worry about that.  Once you have established principal video, all other video should be aligned based on video frames, not audio samples.  Unless you shoot with genlock, your video frames are not going to be perfectly in sync, which means that other video tracks could be as much as a half a frame early or late when aligned on a frame boundary.  Such is life.  Audio that's off by half a frame is not unlike sound that's coming from 21 feet away instead--about a 20ms delay.  There's nothing to do about that because (1) video needs to sync to video--you cannot slip it half a frame, and (2) you're not using audio from the other video tracks, you are using your Zoom audio, and that can only be locked to a single reference point.
If you are really OCD about timing, you can average your video offsets, weight them according to which is most prevalent/important, and align the audio so that lies at that weighted average point.  I don't know anybody who does this, but if you have two video streams that are 1/2 frame apart (worst case) and you split the difference with the audio, your audio/video error changes from 1/48th of a second worst case to 1/96th of a second worst (and best) case.  Only you can tell if that's preferable to you.


text:
How do I replace my organisation's event video camera?
The Camera
My organisation has a Panasonic HC-V700 for event video.  The video end product consists entirely of a single person standing at a lectern and is published on YouTube.  I usually set up the camera by mounting it on a tripod, manually focussing on the subject, connecting the audio, turning on record at the start of the event, and stopping the record at the end of the event.
I would like to replace this with the Canon EOS Rebel T5i which was purchased by the event organiser for stills, along with EFS 55-250 mm lens.
Audio
Audio is supplied via line feed.  I use a mixer and headphones to check the levels before feeding the audio to the camera.
Venue
The venue is indoors, and lighting is usually poor.
The camera is usually located at the back of the room, and is in a fixed position, and no zooming is required.
The Questions

Will this replacement camera deliver a better result?
What configuration does it need to do the job?

Firstly, that camera has a 29 minute 59 second recording limit. If your speaker goes for longer than this it may not be suitable. Apparently this is due to some countries charging higher import duties for video cameras, but if it records less than 30 minutes it's not classed as a video camera. Yeah, I know.
The DSLR will probably cope better with low light due to its larger sensor, and it will give you a shallower depth of field, meaning that you can get a blurry background and sharp foreground, which has a more cinematic feel. Of course if you want the background to be sharp this may not be such a good thing, and it also means you will also have to be more careful about focus.
If you're filming from a long distance you might want to see which camera has the better zoom. At least with the t51 you can buy a longer lens.
Audio on that camera should be fine, you might want to make sure the level is set to manual, otherwise it will turn the volume up everytime the speaker pauses.
As for settings, that depends on how you want to shoot. You could set it to full auto and let it drive, or you could go full manual so that you're in control, or you could use something in between. The aperture and ISO etc. will depend on the light levels in the room, and how much depth of field you want.

You can get around the 30 mins limit by using the Magic Lantern custom firmware. Ore use a HDMI DVR, which might be better / more reliable than recording to SD cards anyway.

@stib Thanks, I appreciated your answer.  I think on reflection we would continue to use the existing video camera.

source: Stack Exchange

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/

sort: votes


text:
How can encode video with images like these (overlay a video over a fixed image) with ffmpeg?

How can encode video with images like these help me ffmpeg ?

It's unclear what you're asking. Do you want to know how to stack multiple images horizontally and then overlay another image on top?

video located at the center of an image please help me how to be able to do

To overlay a half-sized version of a video in the center of an image, use
ffmpeg -loop 1 -i image -i video
-filter_complex "[1]scale=iw/2:-1[ovrl];
                 [0][ovrl]overlay=(main_w-overlay_w)/2:(main_h-overlay_h)/2:shortest=1[v]"
-map "[v]" -map 1:a -c:v libx264 -c:a copy output.mp4

To frame the video:
ffmpeg -loop 1 -i image -i video loop 1 -i frame
-filter_complex "[1]scale=iw/2:-1[ovrl];
                 [2][ovrl]scale2ref=iw*1.2:-1[fr][ol];
                 [fr][ol]overlay=(main_w-overlay_w)/2:(main_h-overlay_h)/2:shortest=1[fv];
                 [0][fv]overlay=(main_w-overlay_w)/2:(main_h-overlay_h)/2:shortest=1[v]"
-map "[v]" -map 1:a -c:v libx264 -c:a copy output.mp4

If you composite the frame onto the background image beforehand, in ffmpeg or elsewhere, you can just use that resultant image with the first command. Of course, you'll lose freedom of movement for the video overlay.

error output video without sound

corrected audio mapping

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/


text:
After Effects: controlling slider in ExtendScript
I'm newbie in After Effects. I've learned how to control slider from expressions. Now I need to get value of slider in script (jsx/extendscript). How can I achieve that?
I've tried (in *.jsx): var a = comp.layer("Slider 1").effect("Slider Control")("Slider")[0];
Result:

After Effects error: Unable to call "setValue" because of parameter 1.
  Value "NaN" of element 0 in the array is not a valid float.

It means that value of slider is not set yet?
Thanks
EDIT:
Here is a example:
var slider = comp.layers.addNull();
slider.name = "Slider";
slider.effect.addProperty("ADBE Slider Control")("Slider");
slider.effect("Slider Control").property("Slider").setValue(100);

var a = slider.effect("Slider Control").property("Slider");
var titleTriangle = comp.layers.addShape();
titleTriangle.name = ("Title Triangle");
var titleTriangleGroup = titleTriangle.property("Contents").addProperty("ADBE Vector Group");
var titleTriangleFill= titleTriangleGroup.property("Contents").addProperty("ADBE Vector Graphic - Fill");
titleTriangleFill.property("Color").setValue([0.68,0.29,0.29,1]);

// using 'a' here
titleTriangle.property("Position").setValue([a,188]);

Please paste all code here. It is difficult to understand, where can be problem, when you are seeing only part of code.

@Shultc, thank you for response. I have added an example.

Sounds like you need to know about Redefinery's RD_Gimme_Props script. It's a script that allows you to find the correct path for any composition element: http://bit.ly/1XTIzh0 There's a whole bunch of tools there for extendscript developers.

I found out - .value after slider.effect("Slider Control").property("Slider") and it works.
var a = slider.effect("Slider Control").property("Slider").value


text:
ffmpeg: Quickly get frames every n seconds from a remote file, downloading as little data as possible
I have a remote MP4 file that is short (1 minute) but large (~450mb), something like this:
https://s3-eu-west-1.amazonaws.com/worm-web-assets-prod/GOPR7775.MP4
I'd like to extract frames every n seconds (where n is >0.5, probably 1 or 2) in the most bandwidth-efficient way possible - i.e. without downloading the whole video. I care less about getting a specific frame than I do about getting one in the general area with the smallest amount of bandwidth usage.
I've found I can get the keyframe list like this:
ffprobe -select_streams v -show_frames \
-show_entries frame=pict_type \
-of csv https://s3-eu-west-1.amazonaws.com/worm-web-assets-prod/GOPR7775.MP4 \
| grep -n I | cut -d ':' -f 1

But this involves downloading the entire video.
I can also download the actual keyframes:
ffmpeg -i \
https://s3-eu-west-1.amazonaws.com/worm-web-assets-prod/GOPR7775.MP4 \
-vf select='eq(pict_type\,I)',setpts='N/(239.76*TB)' out%09d.jpg

But again, this downloads the whole video.
I've also found I can download specific frames:
ffmpeg -noaccurate_seek -ss 00:00:01 -i https://s3-eu-west-1.amazonaws.com/worm-web-assets-prod/GOPR7775.MP4 -frames:v 1 frame-1s.jpg

But this seems to use a lot of data for each frame (>5mb).
Is there a way to achieve this with minimal bandwidth usage?

Are you able to manipulate the file on the remote server? Create new files?

Sadly not - the "remote server" is actually a GoPro camera, accessed over wifi...

Then I don't see a way to do it with off-the-shelf s/w. Basic method would be to download the MOOV box from the MP4, read the STSS box to get the list of keyframes, then fetch those packets only. But to do this, you'll have to code in C. There may be some paid s/w that does this, but not aware of any.


text:
Fast VP9 still image encoding
I use this command to create "myFile.webm", a VP9 video with one still image :
$ ffmpeg -i myOriginialPureAudioFile.opus -loop 1 -i myAudioFile_640x360.png -shortest -threads 4 -speed max -c:a copy myFile.webm
Input #0, ogg, from 'myOriginialPureAudioFile.opus':
  Duration: 01:53:19.80, start: 0.000000, bitrate: 24 kb/s
    Stream #0:0(eng): Audio: opus, 48000 Hz, mono, fltp
    Metadata:
      LANGUAGE        : eng
      TITLE           : unnamed
      ENCODER         : Lavf57.83.100
Input #1, png_pipe, from 'myAudioFile_640x360.png':
  Duration: N/A, bitrate: N/A
    Stream #1:0: Video: png, rgb24(pc), 640x360 [SAR 72:72 DAR 16:9], 25 fps, 25 tbr, 25 tbn, 25 tbc
File 'myFile.webm' already exists. Overwrite ? [y/N] y
Stream mapping:
  Stream #1:0 -> #0:0 (png (native) -> vp9 (libvpx-vp9))
  Stream #0:0 -> #0:1 (copy)
Press [q] to stop, [?] for help
[libvpx-vp9 @ 0x5655578268c0] v1.3.0
Output #0, webm, to 'myFile.webm':
  Metadata:
    encoder         : Lavf57.83.100
    Stream #0:0: Video: vp9 (libvpx-vp9), yuv420p, 640x360 [SAR 1:1 DAR 16:9], q=-1--1, 200 kb/s, 25 fps, 1k tbn, 25 tbc
    Metadata:
      encoder         : Lavc57.107.100 libvpx-vp9
    Side data:
      cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: -1
    Stream #0:1(eng): Audio: opus, 48000 Hz, mono, fltp
    Metadata:
      LANGUAGE        : eng
      TITLE           : unnamed
      ENCODER         : Lavf57.83.100
frame= 4863 fps= 22 q=0.0 Lsize=     987kB time=00:03:14.48 bitrate=  41.6kbits/s speed=0.879x

The speed is about 0.88x, how can I make this encoding much faster ?

Why use VP9? x264?

@Gyan Because, I don't want to re-encode the 2hours audio which in opus format. I use -c:a copy because the WebM container supports opus audio

So does MP4 with -strict -2 added.

@Gyan I don't think YouTube is going to accept an MP4 file with opus audio

Try a very short file.

@Gyan It works, thanks. But I think I'll stick to standard webm file.

On my machine, speed=0.953x while using the default setting
c:\ffmpeg\ffmpeg -y -i out_music.opus -loop 1 -i temp.png -shortest -threads 4 -speed max -c:a copy  myFile.webm

frame=  184 fps= 24 q=0.0 Lsize=     843kB time=00:00:07.32 bitrate= 943.8kbits/s speed=0.953x

speed=1.73x while using the realtime setting
c:\ffmpeg\ffmpeg -y -i out_music.opus -loop 1 -i temp.png -shortest -threads 4 -speed max -c:a copy -deadline realtime myFile.webm

frame=  491 fps= 43 q=0.0 Lsize=    1809kB time=00:00:19.60 bitrate= 755.9kbits/s speed=1.73x

Since the input is a png file, frame per second could be lower; speed=5.84x while using the fps=5 setting
c:\ffmpeg\ffmpeg -y -i out_music.opus -loop 1 -i temp.png -shortest -threads 4 -speed max -c:a copy -deadline realtime -vf fps=5 myFile.webm

frame=  218 fps= 29 q=0.0 Lsize=    1316kB time=00:00:43.40 bitrate= 248.3kbits/s speed=5.84x

Reference:https://trac.ffmpeg.org/wiki/Encode/VP9

Just for information. According to ffmpeg filters documentation on the fps filter, -vf fps=5 would be equivalent to -r 5 as an output option, read man ffmpeg  | sed -n "/-r.:/,/output option/p"

One solution (found here) is to use a very small -framerate value.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


text:
What are the free livecast/livestream services with very low latency
What are the free livecast/livestream services with very low latency (below 3 seconds) ?
I tried YouTube Live but I couldn't keep the latency below 10 seconds.

Free + very low latency can’t exist for long in the current market. The lower the latency, the higher the bandwidth costs per gigabyte.

Can you guys please say why you have down-voted my question so I don't make the same mistakes in the future ? Thank you for your comprehension

This first part should be a comment, but I don't have the reputation to add it as such:
Can you add more details as to your end goal is?  I suspect that you are not streaming to the general public if you need a less than 3 second latency and are instead trying to get video from one device to another.
Answer: If I am right, and you are technically inclined, look into using netcat. See Demo video,  Tutorial

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


text:
What are the WebM (VP9+opus) encoding settings compatible for YouTube import for a video with a still image?
What are the WebM (VP9+opus) encoding settings compatible for YouTube import for a video with a still image ?
I tried PAL and NTSC framerates with 48kHz stereo and and image size of 640x360 and kept every other parameters' defaults :
$ ffmpeg -i myOriginialPureAudioFile-CUT.opus -i myAudioFile.png -ac 2 -s 640x360 -strict strict -r pal myAudioFile.webm

But YouTube says :

The video has failed to process. Please make sure you are uploading a
  supported file type.

Rather than framerate, the issue is there's only one frame. You'll have to loop the image.
ffmpeg -i Audio.opus -loop 1 -i image.png -pix_fmt yuv420p -ac 2 -s 640x360 -strict strict -r pal -shortest myAudioFile.webm

-loop 1 : infinitely loops over the same image
-shortest : stops encoding when the shortest input stream has entirely been encoded

It took 73 min to encode with a 6 min audio source file, are the video frames encoded in differential ? I wonder, since the resulting file is bigger than I expected

are the video frames encoded in differential ? --> yes, they are. The VPx encoders are much slower than the MPEG encoders (x264..). You can add -speed 8 to get a ~2x boost. Although your system appears to be slow, since I get 1x speed (without -speed) for a 640x360@25fps encode.

I have an A4-6210 with 8GB of RAM which I bought in the end of 2014. How old is your hardware ? How often must one renew his hardware ?

I tested on a 2013 Ivy i5 with 16GB. Passmark shows your CPU to be 1/3rd speed.

There is something I still don't understand, if the video frames are encoded in differential, the differences between each frame and the previous should be "0" because we are looping on the same picture. Why does it take VP9 so long to encode "0" difference frames ?

It doesn't know that the image is looped - that happens on the input side, via ffmpeg's image reader. It will still perform motion search..etc

Even if it does not know the image is looped, it should detect that there is no motion in the input hence an easiest encoding, don't you think ?

it should detect that there is no motion --> what should detect - the encoder It does, by running the motion search.

Is'nt the motion detection faster when there is no motion in the input ?

@SebMa only if ffmpeg could give that information to VP9 encoder more efficiently.


text:
No video editor will work with my MP4 file
I have an MP4 file, and I've tried importing it into Windows Movie Maker, iMovie and Final Cut Pro. In all three programs, the video seems to import just fine, but I can't preview it. It appears in a black bar in the timeline, and the preview window stays black even while it 'playing'.
The video was shot on a Sony PMW-EX1R, and I transferred the contents of the SD card straight to my computer, and I am now attempting to work with the MP4 file that was on the card.
I understand that this is not the correct way to do it and the camera probably uses a codec not supported by the programs mentioned above, but the MP4 file plays just fine in VLC, and all three video editors work with .MP4 and .MOV video shot on my Nikon D3100.
So, how can I get the files to play nice with my editor? Do I need to convert them? Change a setting somewhere?
EDIT:
Under the 'more info' option in finder, where the dimensions of the video would normally be, there's nothing.
EDIT 2:
Here's the results of mediainfo:
General
Complete name                            : Documents/Removable Disk/BPAV/CLPR/184_0028_01/184_0028_01.MP4
Format                                   : MPEG-4
Commercial name                          : XDCAM EX 35
Format profile                           : Base Media / Version 2
Codec ID                                 : mp42
File size                                : 923 MiB
Duration                                 : 3mn 31s
Overall bit rate mode                    : Variable
Overall bit rate                         : 36.5 Mbps
Encoded date                             : UTC 2015-06-19 18:52:18
Tagged date                              : UTC 2015-06-19 18:52:18

Video
ID                                       : 1
Format                                   : MPEG Video
Commercial name                          : XDCAM EX 35
Format version                           : Version 2
Format profile                           : Main@High
Format settings, BVOP                    : Yes
Format settings, Matrix                  : Custom
Format settings, GOP                     : M=3, N=12
Codec ID                                 : 61
Duration                                 : 3mn 31s
Bit rate mode                            : Variable
Bit rate                                 : 35.0 Mbps
Width                                    : 1 920 pixels
Height                                   : 1 080 pixels
Display aspect ratio                     : 16:9
Frame rate mode                          : Constant
Frame rate                               : 25.000 fps
Standard                                 : Component
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive
Compression mode                         : Lossy
Bits/(Pixel*Frame)                       : 0.675
Stream size                              : 884 MiB (96%)
Language                                 : English
Encoded date                             : UTC 2015-06-19 18:52:18
Tagged date                              : UTC 2015-06-19 18:52:18
Color primaries                          : BT.709
Transfer characteristics                 : BT.709
Matrix coefficients                      : BT.709

Audio
ID                                       : 2
Format                                   : PCM
Format settings, Endianness              : Big
Format settings, Sign                    : Signed
Codec ID                                 : twos
Duration                                 : 3mn 31s
Bit rate mode                            : Constant
Bit rate                                 : 1 536 Kbps
Channel(s)                               : 2 channels
Sampling rate                            : 48.0 KHz
Bit depth                                : 16 bits
Stream size                              : 38.8 MiB (4%)
Language                                 : English
Encoded date                             : UTC 2015-06-19 18:52:18
Tagged date                              : UTC 2015-06-19 18:52:18

Paste the results of Mediainfo for the file. Use View -> Text mode and edit it into your question using the code formatting.

Transcode your MP4 to MOV and try. Download 32-bit static build of ffmpeg for Windows. Run ffmpeg -i input.mp4 -c copy output.mov from a command line where 'input' is the filename of your MP4.

@Mulvya I have a Mac. Are there any similar utilities for Mac?

Try the Mac version: https://evermeet.cx/ffmpeg/

@Mulvya How long should ffmpeg take? There's just a '>' prompt in my terminal and the process doesn't seem to be using any system resources as I imagine a file conversion would.

Hardly any time. The command won't re-encode the file, only copy the audio/video streams to a Quicktime MOV container.

I used handbrake to re-encode the video as .MOV, and then it worked just fine.
I suspect ffmpeg would work too, but I couldn't find the output so I can't be sure.

The output will be in the same folder as where you unpacked the ffmpeg binary or the same folder as the input (depending on whether the ffmpeg is in the Mac equivalent of the path variable).

You probably have to install or update Pro Video Formats on your mac. https://support.apple.com/en-us/HT202252


text:
Wireless HDMI from camera to mixer?
I would like to stream video from a camera through its HDMI output to a mixer.
Extensive googling has only turned up solutions for streaming from PC's and phones onto a screen.
What I need is a dongle that plugs into the HDMI output of the camera, and transmits the video to a reciever.
The transmitter will need to be fairly small and not need mains power, as the point of having the wireless link is to be able to move the camera anywhere within a 30 meter range. The reciever can be any size and run off any power source.
Does such a product exist? Can anyone suggest one that is no more than £200?
EDIT:
Based on the answers I've recieved, I'd like to add a few points to explain why I want this particular solution;

The venue is more or less circular, with a stage at the front, and
about 400 seats, with four aisles between them. One camera is mounted
to the wall on the right (when facing the stage), on the left of the
far right aisle. The other is at the back, also mounted to the wall,
and the third sits on a tripod on the right side of the room.
Usually this is fine, but the angles of the cameras are far from
perfect, and usually microphone stands or peoples heads get in the
way. Also, we often want to get much closer to the stage and show
things up close.
We can't move a camera to the front of the venue near the stage as it
would HAVE to be in the front row of seats (reasons are complicated,
but boil down to stubborn organisers who absolutely cannot be
reasoned with), and then it would be too low to get enough good shots
to be worthwhile.
The cameraman can't trail a long cable, not because of length
limitations of HDMI (the cameras have SDI out) but because people are
coming and going during events and it would present a trip hazard,
not to mention only being able to move up and down the four aisles
makes trailing a long cable annoying for the cameraman.
The footage is being mixed and streamed online in realtime, so having
a camera recording and then doing post production doesn't really
help.

Streaming from the camera to the mixer is the best solution I've been able to come up with, but perhaps I've missed a much simpler option.

What did you end up doing?

@DigiVisionMedia We're still using the same setup. Occasionally we can trail an SDI cable, but only for smaller events, and only in the front row of the venue.

Nitero Is looking to create a wireless solution for VR by the end of this year, which very well may apply to what you need as well. At the very least, if this technology does get off the ground we may see higher fidelity wireless solutions for video be produced off the back of this technology in the coming months/years. Basically, it might be worth waiting a bit to see what pans out, or you can use any of the solutions fredsbend pointed out.

I think eventually, wireless video capture will be a reliable and quality option. We certainly all hope so. Like AJ said previously, however, right now, it is a romantic idea. We are enamored by wireless, automagical options.

There are wireless sdi transmitters, but those are pricey. Why not have multiple cameras and then use a switcher to get different coverage around the venue? Your cameras can still "move" but not around the entire room, hence multiple camera spots.

@A.J.Hernandez That's the setup we currently have - two cameras at either side and one at the back. However, two are fixed to the walls and can't be moved, and the angles with the current setup aren't great. It would be great to be able to move at least one anywhere in the venue to get better shots, although I think we'll have to settle for relocating the one on a tripod until the price of the technology drops.

Cerevo Liveshell 2. It,s battery powered also. As receiving-end use a laptop with vlc player. Hdmi from laptop to mixer. I used this setup a few times.

Yes, they exist. They are called HDMI wireless extenders. Sometimes they are called transmitters/receivers. No, the good ones are not cheap. Further, I don't know of any where the receiver does not need external power.
Here's two examples, a better one and a not so better one:

IOGear Matrix pro (Here's a different offering)
Gefan Long Range Extender

I have no experience with either product and practically none with wireless HDMI as a whole. Personally, I would always use a wire for something like video. If you're only going 30 feet, it's really not a big deal to have a wire, and HDMI can go 30 feet just fine. If you need more distance, there's extenders of various wired variety that I would prefer over wireless options.

From your comment below, it sounds like you are wanting to move throughout the event, therefore making a wireless solution optimal, allowing you to move about on your whim.
If you do not have to stream the feed to the internet, I suggest that instead of running your video wirelessly, run the audio only. Get yourself a wireless audio transmitter and receiver, then carry the receiver around with you and the camera, plugging in the audio receiver to your camera. There are literally thousands of options and should be easy to find with google. Alternatively, get a standalone audio recorder and then mix the audio and video together in post.
The downside of these methods is that you must record to the camera's internal media and it may increase your post production time. The upside is that you're mobile while recording.

Yes, question, why do you "need" wireless? There are sdi converters and fiber converters that go miles. Being wired is super reliable during production. While being wireless is a romantic idea, it's not the best approach.

@A.J.Hernandez I would like to be able to move the camera anywhere within a venue that is about 25 square meters. The venue has about 400 seats, with people coming and going during events, so trailing a long cable is not an ideal solution.

@RyanKrage In that case, yes, perhaps you need a wireless connection, but unless you need to stream to the internet, I think I have a better solution for you. I will make an edit.

@RyanKrage Edit made. Of note, I don't know of any wireless HDMI receivers that do not require an external power source.


text:
Mask not working
In After Effects, I want to use a mask to prevent an area from beein affected by a layer. I created a mask using the pen tool, but instead of masking the shape, the program masks the bounds of the shape. It "draws" a rectangle arround the path and masks everything except the rectangle.
I am a beginner. What am I doing wrong?
Thanks!
Edit:
The mask works for simple layers, but my layer has an beam effect on it.

Masks happen before effects so some act strange. Two main options:

Apply the mask to a solid above your beam and then use Track Matte
Pre-comp your Beam and mask that instead

Thank you. I'm not sure what you mean by the second option, but I can use the first one.


text:
How to make audio "internal editing" in a movie?
I've just read an old blog post about "internal editing", a special kind of audio post processing of recorded interviews. It basically consists of removing the unnecessary interjections, like the "ums" and "ehs" that we normally say while speaking. It improves the rhythm of conversations, and make your interviewee look more intelligent.
If you just have audio, it is simple. You crop out the interjections. But if you have an interview recorded in somewhere with background noise, if you delete the interjections, there will be an weird silence. Deleting it, would unsync the audio and image.
Would someone give me some tips to remove just the voice using an audio editor? A step by step guide would be great.

Hey neves, I saw you requested a move to sound design.  It would also fit there, but it really fits just fine here.  We handle sound related to video here and given that there are going to generally be video related recommendations in the answer, it's probably a better fit here.  If you still want it moved, just reflag it and I can move it, but for now I'm going to leave it here unless you really want it moved.  (I'm a mod on both, as is Rory.)

Instead of deleting the offending bit, overwrite it with room tone, a section of nominal silence either recorded specifically for this purpose at the time of filming, or just taken from a nearby bit of silence.

But how do I integrate tire room tone with three rest of the clip? When I do it, there is a failure when the new sound starts. I'd like to have a kind of blur for audio.

@neves  Maybe if you describe what you're actually doing, and what you mean by 'failure', I could give a better answer. As it is, overwriting a section of audio means replacing it without changing the duration.

I'll try to explain better. When a person sttuter, the audio you want to remove is mixed with the adjacent audio. You will remove it and put some background noise. Since the audio waves won't match perfectly, you will hear a mismatch when the noise starts. What can I do to minimize this mismatch? I'd like to "blur"the two sounds.

@neves  The idea is to replace the unwanted audio with something that closely matches what's 'underneath' it. When the environment is noisy it's hard to get a close match, but audio from very nearby in the timeline is the best bet. And instead of cutting in the segment, do a short dissolve in and out if possible -- place the room tone on a separate track and crossfade.

instead of completely removing the interjections and background sound from between the spoken word try just cutting the actual "umm" (for example) leaving a gap, then copy a bit of the background sound from somewhere slightly bigger than the gap, insert it and crossfade it between the audio. It will then sound as if the background is there with no obvious cuts.


text:
How do I crop a video with a particular point of the video always in the centre of the frame?
Suppose I have a drone video not properly shot, but the subject is always in the frame but not a constant point. Now, I want to crop that 16:9 drone video to a 4:5, and have the subject always in the centre of the video frame.
Is this equal to motion tracking or, perhaps, the reverse application of motion tracking? How would I go about this?

Manual motion tracking in After Effects will do the trick, but it's work. That's why you always want to have or get the best quality footage: "we'll fix it in post" costs time, pain, and money.

The action you're trying to perform is called “stabilization,” which is usually performed by analyzing the entire frame when the goal is to eliminate camera shake, but when you want a single object to stay in place, you'd track a single point, or small area of the target, and apply the same counter-movement that you would to eliminate shake.
In AE, point trackers are under the animation menu→Track Motion.  After you analyze the subject, click the “Stabilize Motion” button on the “Tracker” tab.
If you don't have AE, the free version of DaVinci Resolve can do the same thing, and there are several ways to do it.
Either:

On the Color Page, go to the “Window” tab, add a shape to track, then switch to the “Tracker” tab, select “Stabilizer” from the dropdown, and click “Stabilize.”

or

On the Fusion Page, hit shift-space to call the select tool menu, and start typing “tracker.”
Click OK, hold Shift and drag this new node onto the line connecting “Media In” to “Media Out.”
Move the green box that appears over the area of the footage you want to track, click the “Track Forward” button.
When it finishes, switch to the “Operation” tab and select “Match Move” from the dropdown.

The Fusion method won't zoom in on the result by default, so you'll see black boarders around the edges as the footage moves to compensate, but you can easily zoom in on the edit page, or do it “properly” in fusion by adding a Transform node, and scaling there.

Yes, it is somewhat like a motion tracking, just open your file in AE and then create a null object and track the motion of that video and save the data to the null object, and then parent your video file to the null object.

To my knowledge there is no build in function in FCPX to do that.
Either you could do it by hand with key frames, buy a plugin or maybe better use Apple Motion.


text:
What kind of lighting setup is this?
I'm looking to understand how this person did their lighting setups, what kind of filters they used, and angle of view (35mm equivalent focal length).
From what I can see, there is a ring light and two flolights. Are those the only 3 lights?
What kind of filter did they use to achieve the ultra soft skin tones?
What kind of focal length (35mm equivalent) are they using for his field of view?

In the meantime, I found more pictures of the panels in question. Can anyone identify make and model?

Could you post a link to the video/image source? Maybe metadata can reveal something about the lens.

I doubt that the creator used a ring light, as you would definitely see the reflection of it in her eyes. The lights she used look like your regular Kinoflo or Kobalt. You could use frost, also called white diffusion in front of it to give softer light, but I don't think she used that either. Remember: The bigger the light source, the softer the light (and shadow). Kinoflos are very very big, and especially 4-Banks (flos with 4 tubes of light) give out very soft light on their own, which is why I assume she opted for this specific light.
Technically, her head is kind of disappearing into the dark tv-screen, since the hair and the display have a very similar color. To prevent this, you would usually set up a light on the opposite end of where your keylight points at. This way, you will have a nice bright edge around the back of the head, separating her from the background a bit more.
As so the lens it's very hard to tell, you'd have to go into pftrack and manually track the leading lines etc. However I assume that it's a lens way below 50mm, probably at about 20-25.

It looks like they didn't have a lot of room to play with, so two kinos, mounted vertically at 45° left & right. Quite close in to make it as broad as possible [for which I'd have used them horizontally ;)
I'd also have put diffuser gels right across the barn doors at their widest to try spread it still further.
The end result for such a potentially soft-light setup seems to have come out a bit hard-edged, the shadows in her hair etc. It's also all a bit shiny on her face.
Also, as mentioned , getting a light in back would have helped separation from the TV.
This and the fact they've got one of the kinos reflecting in the TV is what makes me think they didn't have enough room to work & also that they only had those two lights to work with.
As they've used old-fashioned fluorescent tube kinos rather than modern temperature-controllable ones, I'm guessing they mis-judged the light temperature, so the shot has come out quite a way to the magenta side. I can only guess they'd set up for "fluorescent" which doesn't work for standard tube kinos, as they actually qualify as "daylight".
Lens, I can't come up with any better guess than Florian - it's something short. A bigger giveaway would be if they'd gone for a two-shot [or even group shot] so you could see how the edges of frame were affected. With just a sofa & TV in background there's not a lot to judge from. Big nose, little ears [or in this case, big head, little shoulders] is definitely in evidence, but there's not enough for me to guess in a still without knowing what the presenter looks like in real life, or see her in motion on video.
crop/zoom - 2 kinos in eye & hard edge on face


text:
Playhead movement increment is too large in DaVinci Resolve 18
I am trying to move the playhead a small amount to trim a clip with a very fine cut. Howerver, the playhead can only move in relatively large increments. Here is a gif to demonstrate the problem:

Has anyone got an idea how fix that?

Seems you're limited by the frame rate, it cant move between frames, if you play the clip the minimum gap will be a single frame


text:
FFmpeg recover_mp4 help
ive been using ffmpeg and recover mp4 to try and restore a dashcam video from a car accident. im a beginner using this method/ software and im running into this issue. not sure how to "increase analyzeduration and probesize"  any and all help appreciated ASAP
C:\ffmpeg-2023-03-20-git-57afccc0ef-essentials_build\recovery\bin>ffmpeg.exe -r 25.000 -i result.h264 -i result.aac -bsf:a aac_adtstoasc -c:v copy -c:a copy result.mp4
ffmpeg version 2023-03-20-git-57afccc0ef-essentials_build-www.gyan.dev Copyright (c) 2000-2023 the FFmpeg developers
  built with gcc 12.2.0 (Rev10, Built by MSYS2 project)
  configuration: --enable-gpl --enable-version3 --enable-static --disable-w32threads --disable-autodetect --enable-fontconfig --enable-iconv --enable-gnutls --enable-libxml2 --enable-gmp --enable-bzlib --enable-lzma --enable-zlib --enable-libsrt --enable-libssh --enable-libzmq --enable-avisynth --enable-sdl2 --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxvid --enable-libaom --enable-libopenjpeg --enable-libvpx --enable-mediafoundation --enable-libass --enable-libfreetype --enable-libfribidi --enable-libvidstab --enable-libvmaf --enable-libzimg --enable-amf --enable-cuda-llvm --enable-cuvid --enable-ffnvcodec --enable-nvdec --enable-nvenc --enable-d3d11va --enable-dxva2 --enable-libvpl --enable-libgme --enable-libopenmpt --enable-libopencore-amrwb --enable-libmp3lame --enable-libtheora --enable-libvo-amrwbenc --enable-libgsm --enable-libopencore-amrnb --enable-libopus --enable-libspeex --enable-libvorbis --enable-librubberband
  libavutil      58.  4.100 / 58.  4.100
  libavcodec     60.  6.101 / 60.  6.101
  libavformat    60.  4.100 / 60.  4.100
  libavdevice    60.  2.100 / 60.  2.100
  libavfilter     9.  4.100 /  9.  4.100
  libswscale      7.  2.100 /  7.  2.100
  libswresample   4. 11.100 /  4. 11.100
  libpostproc    57.  2.100 / 57.  2.100
[h264 @ 0000025867b3dac0] Format h264 detected only with low score of 1, misdetection possible!
[h264 @ 0000025867b4f940] missing picture in access unit with size 23
[h264 @ 0000025867b4f940] no frame!
[h264 @ 0000025867b3dac0] Could not find codec parameters for stream 0 (Video: h264, none): unspecified size
Consider increasing the value for the 'analyzeduration' (0) and 'probesize' (5000000) options
Input #0, h264, from 'result.h264':
  Duration: N/A, bitrate: N/A
  Stream #0:0: Video: h264, none, 25 tbr, 1200k tbn
[aac @ 0000025867c0e5c0] Format aac detected only with low score of 1, misdetection possible!
result.aac: End of file

C:\ffmpeg-2023-03-20-git-57afccc0ef-essentials_build\recovery\bin>
C:\ffmpeg-2023-03-20-git-57afccc0ef-essentials_build\recovery\bin>

Add -analyzeduration 100M -probesize 100M before each of -i result.h264 and -i result.aac.

Although it looks like your aac file is very short.


text:
Does scale behave differently than position in after effects animation?
In the GIF, if you notice, it looks like the scale is relatively fast at the beginning and gradually becomes slow at the end of loop. So I feel speed of zoom (scale) is not constant:

However, when I adjust the speed graph a bit like this, it makes the speed a bit constant. But that's just an hit and trial and not perfect. I don't understand why the default graph, which seems constant, behaved like that and altered graph, which seems increasing, makes it the way I want:

But when we do any position (x or y) animation (without easy ease), for any object, the speed is constant without any doubt.
So is it true scale behaves differently and scale speed isn't constant? If yes, is there any logical way to make the speed of scale constant (I mean making the zoom look like it's constant)?

This probably isn't the answer you're looking for, but in general I stay away from the speed graph - the value graphs are much easier to understand imho...

I've never encountered this problem but I have a couple of ideas:

An illusion created by the 2 parallel lines getting really close to the edge as it feels like it jumps when you look at the edge of it and doesn't occur when the rotated square hits the edge with its corner.
The loop you made has cut a single frame from the end of it making it look like an imprecise motion, try manually creating a second loop before marking the end of the Work Area.

@Apeiron_Sound I think actually it's not a problem, it's how Scale property works.

I have tried this for a different design too. Faced same thing there also. So I don't think it has to do something with those rectangles.


text:
Creating a split screen effect
I have two videos of the same length and I want to create one video with those 2 in a split screen manner.
I'm totally new to this field and I will probably never need to do this ever again so I'm looking for a quick and easy way that involves free software.
I tried VirtualDub but I'm lost in it's options and settings and I don't even know if it can do what I want to do.
EDIT: Context: each video is a recording of a PC screen. I want to show them in a split screen manner in order to display the way one PC influences the other. Audio is of no importance.

Do you want to show the full frame of both videos or only a portion?

I want to show the full frame of both

What about the audio of each?

Audio is not important.

FFmpeg, a command line tool, can accomplish this, via this command.
ffmpeg -i left -i right -lavfi [0:v][1:v]hstack -pix_fmt yuv420p -an combinedvideo.mp4

Replace left with filename of video to be positioned left. Same with right.
ffmpeg (32bit static build) can be downloaded from here. The ffmpeg.exe is in the bin folder of the archive.

This looks promising. I was able to make a quick test with it. Is there a recommended codec I should use? I tried to play the output .mp4 with Windows Media Player and it didn't work, but it played fine with ffplay. I should also resize the videos before doing this because the output was a bit huge (couldn't fit it on my screen in a mice way)

To resize the output, you can chain on a scale filter, like this: -lavfi [0:v][1:v]hstack,scale=1920:-1 This will produce an output 1920 pixels wide and of proportional height so the video isn't stretched or squashed. The default codec, when one isn't specified explicitly, is H.264, so it's strange that WMP doesn't play it.

I think something it's missing from my PC. When the output isn't .mp4 WMP plays it with no problems. Thanks :)

If you have Quicktime installed, you can just change the final mp4 to mov


text:
Accurate audio selection
How do I select the audio corresponding to a set of filter-selected videoframes?
E.g. at the moment I am sampling 1 in every 100 frames of a video (running at 15fps) using the FFMpeg select filter. When I try to select the audio of those frames with the aselect filter, the total audio duration is not equal to the video duration (2 or 3 seconds difference depending on which frames I selected). The audio sampling rate is listed as 22050Hz.
I tried using various -vsync and -async combinations but it made no difference. Is there a more accurate way of using aselect?
A quick example command:
ffmpeg -i %INPUT% -vf select='between(n\,200\,399)',setpts='PTS-STARTPTS' -af aselect='between(n\,200\,399)',asetpts='PTS-STARTPTS'-y test.mkv
where 'INPUT' is the name of some file containing compressed video and audio. I am testing with the file AV36_1.avi found on this site hosting video samples. I get a video duration of 13.3 seconds and audio duration of 12 seconds.
output:
ffmpeg version N-77045-ga16243a Copyright (c) 2000-2015 the FFmpeg developers
  built with gcc 5.2.0 (GCC)
  configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-av
isynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enab
le-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --
enable-libdcadec --enable-libfreetype --enable-libgme --enable-libgsm --enable-l
ibilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enab
le-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --en
able-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --ena
ble-libtwolame --enable-libvidstab --enable-libvo-aacenc --enable-libvo-amrwbenc
 --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enabl
e-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-libzimg --
enable-lzma --enable-decklink --enable-zlib
  libavutil      55.  9.100 / 55.  9.100
  libavcodec     57. 16.101 / 57. 16.101
  libavformat    57. 19.100 / 57. 19.100
  libavdevice    57.  0.100 / 57.  0.100
  libavfilter     6. 20.100 /  6. 20.100
  libswscale      4.  0.100 /  4.  0.100
  libswresample   2.  0.101 /  2.  0.101
  libpostproc    54.  0.100 / 54.  0.100
Guessed Channel Layout for  Input Stream #0.1 : stereo
Input #0, avi, from 'AV36_1.avi':
  Duration: 00:00:32.93, start: 0.000000, bitrate: 2372 kb/s
    Stream #0:0: Video: indeo5 (IV50 / 0x30355649), yuv410p, 320x240, 2058 kb/s,
 15 fps, 15 tbr, 15 tbn, 15 tbc
    Metadata:
      title           : Steyr.avi ┬ΦΣσε #1
    Stream #0:1: Audio: adpcm_ms ([2][0][0][0] / 0x0002), 22050 Hz, 2 channels,
s16, 176 kb/s
    Metadata:
      title           : Sound Forge 4.0 Audio
Output #0, avi, to 'test.avi':
  Metadata:
    ISFT            : Lavf57.19.100
    Stream #0:0: Video: mpeg4 (FMP4 / 0x34504D46), yuv420p, 320x240, q=2-31, 200
 kb/s, 15 fps, 15 tbn, 15 tbc
    Metadata:
      title           : Steyr.avi ┬ΦΣσε #1
      encoder         : Lavc57.16.101 mpeg4
    Stream #0:1: Audio: mp3 (libmp3lame) (U[0][0][0] / 0x0055), 22050 Hz, stereo
, s16p
    Metadata:
      title           : Sound Forge 4.0 Audio
      encoder         : Lavc57.16.101 libmp3lame
Stream mapping:
  Stream #0:0 -> #0:0 (indeo5 (native) -> mpeg4 (native))
  Stream #0:1 -> #0:1 (adpcm_ms (native) -> mp3 (libmp3lame))
Press [q] to stop, [?] for help
frame=   98 fps=0.0 q=9.6 size=     294kB time=00:00:09.03 bitrate= 266.1kbits/s
frame=  200 fps=0.0 q=11.7 Lsize=     525kB time=00:00:13.33 bitrate= 322.5kbits
/s
video:429kB audio:72kB subtitle:0kB other streams:0kB global headers:0kB muxing
overhead: 4.625268%

I think I'm using the aselect filter wrong...

Paste your command line used and console output.

@Mulvya done :)

Please reformat the console properly, like first box here.

Your command is selecting all frames from #200 to #399, not 1 of 100, and your sample file is indicated as "Very strange avi sample containing some stray LIST fixed by r20118" Maybe try with a sane sample. I'll test myself in the evening and get back

The exact selection doesn't matter, the point is that the corresponding audio selection has a large duration discrepancy. This trivial example should involve less possible complications than a more involved selection of frames (like not(mod(n,100)) -vsync 0). It would also be harder to select the corresponding audio frames.

Looks like a known problem: http://superuser.com/q/866144/114058

@Mulvya Meanwhile I think I discovered it is because of the audio framerate difference. I assumed it equal to the video framerate. The problem in your link assumes the audio framerate is 48fps because the sampling frequency was 48kHz. But it seems both assumptions are dangerous. In this case the audio framerate is about 21.8fps. By correcting the aselect frames with a factor 21.8/15 I get a much more accurate audio track. A few milliseconds difference. :D

If aselect is using audio frames for reference, then try 22.05/15 and if that makes it more accurate

@Mulvya No, the audio framerate is not 22.05fps. According to ffprobe it is 22311/1024.

This command, which used t reference for aselect, worked for me:
ffmpeg -i AV36_1.avi -vf "select=between(n\,200\,399),setpts=PTS-STARTPTS" -af "aselect=between(t\,(200/15)\,(399/15)),asetpts=PTS-STARTPTS" -y test.mkv

If you want to use n (frames), then you will need to know the frame size of the audio codec e.g. 1024 samples for AAC, variable for MP3..etc

Cool, but this conversion won't work if the video has variable framerate. The info about audio frame sample sizes is interesting, I thought the sampling rate (22050Hz in this case) was always constant over time.

Sampling rate is constant, but compressed audio streams chunk n samples into frames which don't correspond to video frame boundaries. Your method won't work for VFR either, as the audio frame rate you're getting from ffprobe is CFR. A path to a general solution is to obtain the PTS of the first and last selected video frames and then supply the equivalent times to the aselect filter.

Then it seems timestamps are the safest way. So would an mp3 frame with 100 samples last 10 times longer than a frame with 10 samples? If aselect can only select entire audio frames this could limit accuracy. But my gut is telling me that aselect selects samples instead of frames (when using timestamps at least).

No. Depends on the sampling rate. If you have a 48000 Hz rate, then a typical 1152 samples MP3 frame is 0.04166 seconds of audio. If 24000 Hz, then 0.0833 s.

but a typical MP3 frame does not exist, as they have a variable frame size...so some frames will have 1500 samples, others 900, etc. Ah but the timestamps might not be as linear as with video.


text:
FFMpeg encode with original codec
I know about the -c copy switch with ffmpeg, but this does not work with filters as it means "don't re-encode". But what I want is to have my output use the same stream formats as my input. So if I scale and remux some file "input.avi" at 1920x1080 to "output.mp4" at 1280x720 I want the video and audio streams to be in the same format (i.e. re-encoding is OK but don't use a different codec).
Currently I need to specifically choose the codecs otherwise ffmpeg will use some default codecs based on the container--not based on my input formats. Is there any switch for this?
Note that I want to retain the formats, the specific encoder is not really important. E.g. As long as I can get H264 I don't care if it uses libx264 or some other 'competitor'.
On a side note, does ffmpeg has a command to list the defaults per container, or is it only available in external documentation?

Not all containers support the same codecs. In your example, you posit a AVI -> MP4 remux. Well, MP4 spec doesn't support PCM audio, so a source AVI with that audio codec will fail encode to a MP4.

FFmpeg doesn't include a corresponding encoder for each codec decoder it has, so some streams it can read but not write. Again, encoding failure. AFAIK, you'll have to specify the codecs explicitly.

@Mulvya if the container doesn't support the codec it should just give an error--like normal. 1) Assume the user knows the target container can handle the codecs. 2) Assume that FFmpeg has encoders for the relevant formats. It seems my case should be pretty common, and that it would not be hard to implement such a "copy" switch.

ffmpeg -h encoder=label will list all the parameters that the encoder accepts. If a default is set, it's (usually) noted. So, for Xvid, you should run ffmpeg -h encoder=libxvid


text:
Graphics card and video codecs: are colors stored in a linear scale?
Is this saying correct ?
The graphics card and most video codecs store colors in a linear scale.

If by linear scale, the (Cinelerra manual) "saying" means gamma = 1.0, then that's not my understanding of most video codecs.
GPUs, OTOH, probably do operate upon values decoded and stored as a linear representation of a higher precision than the source, which would be typically 8-bits per channel.

The correctness of this statement depends on the color model. The statement will typically be correct for color models such as RGB and CMY. In HSx (HSV, HSL) color models the model doesn't store explicit colors, and their transformation to explicit colors is non-linear.
EDIT:
My comment below on YUV is incorrect, YUV transforms linearly to RGB, thanks @Mulvya!

How about YUV (YCbCr) ?

YUV does not transform linearly to colors, see the transformation formula in https://en.wikipedia.org/wiki/YCbCr#YCbCr

a) the YUV<->RGB conversion is linear, they are of the form AX + BY + CZ + D  b) the statement that the OP quotes is from the manual of a video editor (Cinelerra). CMY, HSx models don't come into it. Even those codecs which store video as RGB e.g. qtrle or x264rgb, don't store linear RGB values (by default).

@Mulvya maybe you are correct, but I understood the OPs wording "YUV (YCbCr)" as meaning Y'CbCr which AFAIK maps to RGB non-linearly.

The wiki page you linked to, has the formulae, which are all linear.

Thanks, I stand corrected, what got me confused is: "Y′ (with prime) is distinguished from Y, which is luminance, meaning that light intensity is nonlinearly encoded based on gamma corrected RGB primaries"; of course the light intensity can be non-linearly encoded and still retain linearity with RGB values. I'll edit my answer to reflect the problem with my above comment.

Not likely, most monitors and most display devices have a nonlinear response. This is useful, as human eyes are not linearily sensitive.
Having the data stored in nonlinear scale is thus a very simple compression scheme. In fact, your display device depends on this gamma correction. If you would not have a gammacorected datasource then the image would appear dark. While this image could be corrected you would lose color data as the values would get nonliearily distributed. End result is that 8bit color would no longer be enough to display continious color without banding. This is why cameras have 10, 12 or 14 bit sensors, as he sensors themselves are linear in nature.
So while it certainly is possible to have colorspaces that are linear, most videosoursces would not be linear. Simply because that would mean need to store over 8 bits of color info. Codecs certainly can have different settings and many of the color modes would not be practical without nonlinear data.
In general its rather safe to assume that the data stored is not linear even if stored in a space that could represent linear data. Unless the source specifically mentions its linear and it stores more than 8 bit color then it most likely is not linear.

From wiki: Human vision, under common illumination conditions (not pitch black nor blindingly bright), follows an approximate gamma or power function, with greater sensitivity to relative differences between darker tones than between lighter ones.

@Mulvya hmm... Its a bit trickily worded to parse correctly. Fixed.


text:
Tabify text inside Sony Titles & Text
The editor won't respect the space that I insert with the TAB key, it does (unsurprisingly) with regular spaces (won't match the same space length between lines at all, however). Is there a way to make Vegas respect them? Perhaps by using some special character instead?
The workaround would be to make another text clip in parallel with this one, but I want to know if this can be achieved without doing that.


text:
Premiere Pro: Possible to add several images on one video track?
I have this image

that I want to put on top of my video, like this:

And I want to fill the entire screen with multiple copies of this image. However, the only solution I've found so far is to create a new video track for each image. So if I want 100 images, I need 100 video tracks. Is there any other solution to this?
Premiere pro:

If you want a hundred images at the same time, you need 100 layers. Often people will make a "pre-comp" which is a nested composition. You create a composition with only the images, then insert that composition into the main timeline. Any changes you make to the pre-comp will carry through even after you've laid it into your main video timeline. So your pre-comp will be the messy one, and your final comp will be nice and neat.

If that's a static image, you could:

open up an image editing program (even a simple one like MS Paint)
copy-paste it 99 times, positioning each new image below the previous one
save that as a single image file
drag that single image file into your Premiere timeline

But it looks from your example screenshot that you want each instance of the image to sort of appear one after the other on screen.  If that's the case, you could use the above technique to make, like, 10 copies of the image.  Then in your timeline, you add 9 instances of the original image, and when the 10th one is supposed to appear you replace the first 9 instances (and the new one) with the 10-instance image that you created, so it only takes up one track. Then you add another 9 instances, one at a time, then replace all of those with the 10-instance image that you created. At that point you'll have 20 instances of the original image but only be taking up 2 tracks. (This may not work at all, based on how you actually want them to appear. Just thought I'd suggest it in case it does work for you, or it leads you to another solution that does what you want.)

Image program seems to be the best bet here

He can also the single image thing and animate position and mask to make different portions appear at different times.

@Mulvya Wow, really good thought!!!

I actually have a solution that puts it in one track! Drag over a title sequence from Essential graphics, and while inside the edit panel use CTRL-ALT-T (a shortcut I added to 'Add New Layer From File') and the folder explorer will appear for you to choose as many images as you'd like to add. Then you can simply delete the original elements for the title sequence. Voila! One clip with all the images you need, each with their own individual controls. Hope this helps!


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Video (or audio, too) format that stores multiple languages in the same file, but only the parts that are different?
DVDs or similar often offer different dubs of the same movie, TV show, etc. on one disk.  Storing a whole different video track (and audio track, too) for a movie seems a bit wasteful, given that the parts where nobody actually speaks (and, for that matter, when no on-screen text needs to appear in another language) don't need to be duplicated.
So, instead, why not provide the whole movie in some "canonical" language (maybe English), and then if other languages are available only store the parts of the movie that actually need to be translated, seamlessly loading them as needed?  Is there a video or audio format that does something like this (not necessarily on DVD)?

I've never seen a DVD with 2 versions of a video stream. For audio it isn't really worth the trouble unless you want to support like 20 languages in a long movie that only has a few dialogues.

You don't need separate video tracks. All the differences are in the audio, which is a minuscule part of the overall data on a BVD. It's a simple matter for a player to select one of multiple audio tracks.

He wants to store only the 'diff' for the audio as well. The video stream may differ if there's on-screen text like a location/time announce like "London, 5 years later".

Very interesting thought. In some films on screen text (e.g. signage) is changed. One could imagine a sort of patch being played instead of the "original" image. I imagine one could code something like that together in html5 for digital delivery. I don't think, however, that it's possible on the existing disc platforms.
In any case the use cases are few.

On the post-production level obviously you have this. It happens that you edit separate language versions at the same time,  using a multitrack audio file that contains a basic mix and then the parts that are different in each language. On the distribution level, as somebody mentioned (for home use), there is no real need for that, the audio part of the movie is so small in comparison to the video part, I guess the logic that would be necessary to achieve the "overlaying" of audio would be more complex than the advantage (by saving a little space). In the cinema world dolby atmos is gaining some ground and it seems it is slowly entering the home cinema world as well. With dolby atmos, this idea is entirely possible and probably exists already.
As far as I understand dolby atmos, it contains the raw tracks with mixing information (volume, panning) as meta-data which can be applied to different setup, room sizes or language versions (as in your question)


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How to: Add Chapters, Sections, markers to video files to help direct access, skipping/ fast forwarding?
How to: Add Chapters, Sections, markers to video files to help direct access, skipping/ fast forwarding?
PS: Asking for Non ISO video file formats that support these: MKV does for sure, I am wondering about other most popular video file formats such as:

MPG
MP4
AVI
M4V
MKV
FLV
MOV/ QT

https://superuser.com/questions/240981/how-to-add-chapters-or-bookmarks-to-movies
The above similar question was for Mac only, and this one is asking for bit more.

What video file formats support such markers
How can a person easily add such markers to existing video files?

PS: Prefer a free/ non-commercial way of doing so on Windows.

MP4 format does support chapters. You can use free Drax utility to create them. Please note that not all video players support MP4 chapters. You need to find one that does (VLC ?)

What about MPG, AVI files? Can they support (when playing via VLC?)

VLC does not save the bookmarks for future viewing of the mp4.


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Easily convert & archive a bunch of low res Video CD DAT files MPEG 1/2 to newer better format such as MKV or others?
Each file is around 350-650 MB.
This is the media information from the Files:
https://i.sstatic.net/kBcWf.png

How could I better archive it?
Easily convert & archive a bunch of low res Video CD DAT files MPEG 1/2 to newer better format such as MKV or others?

Using ffmpeg, a free command-line tool, you can convert these DATs to MP4 (or MKV):
ffmpeg -i input.dat -c:v libx264 -crf 20 -c:a aac -b:a 128k -movflags +faststart output.mp4

Your VLC output doesn't mention it but if the inputs are interlaced (likely), then use
ffmpeg -i input.dat -vf yadif -c:v libx264 -crf 20 -c:a aac -b:a 128k -movflags +faststart output.mp4

When you say archive, do you mean for long-term storage, such as in a library or museum? If that's the case a lossless, well-documented, open-source codec and container is what you want. FFV1 in a matroska continer (.mkv file) is my preferred archival codec / container format, and it's gaining popularity in the GLAM sector.
Once again, FFMPEG is the tool of choice for making these–FFV1 is a codec developed by the creators of FFMPEG. A good page on how to encode FFV1 here, and an example would be:
ffmpeg -i input_video.dat -c:a pcm_s16le -c:v ffv1 -level 3 -coder 1  -context  1  -g 1  output.mkv

For archival purposes I would not de-interlace because of the loss of resolution, and because it alters the source substantially.


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Easy quick way or tool to selectively pull Snapshots / Frames from a Video and put it into a Comic Strip type structure?
Easy quick way or tool to selectively pull Snapshots from a Video and put it into a Comic Strip type structure?
Take a minute long mp4 video and pull specific snapshots into a set of comic strip type of frames / story board type of layout.
Additionally, add some annotation text to frames if & when needed; manually or from the subtitles (embedded, inbuilt or external - .srt / .sub/ .txt)
Simple way / tool/ steps to do this?
PS: I am aware that Major / Big Video & Photo shop type programs will have/ allow way more than this. I am looking/ hoping to do this in a quick light way - maybe repeatedly for some videos.
If more context helps, I am trying to comic strip frames some stand up brief comedy routines' setup to punch-liners into static frames.
I wonder if such features can help?
Good app / process for organizing video snapshots into a storyboard?

This is not really a question about video production. For multiple screenshots you might use ffmpeg (parameters: https://trac.ffmpeg.org/wiki/Create%20a%20thumbnail%20image%20every%20X%20seconds%20of%20the%20video) but for a tool that turns those into a comic strip you might get an answer on https://graphicdesign.stackexchange.com/ more quickly.

@Matt - Its more 1. selective Video Frame & 2. Subtitle extraction than it is just plain
Screenshot taking. GD folks would probably flag and send me back saying its a video thing. Its more Storyboard / Video / Motion pictures than it is static Graphic Design.


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Mac video capture / recording at a resolution larger than, and aspect ratio different to, native display
Goal: I'd like to upscale a recording from a 1680 x 1050 (16:10 aspect ratio), 2010 Macbook Pro screen to 1920 x 1080 (16:9) for 'best-try' upload to a variety of target platforms (FB, YT, Vimeo etc).
Note: thanks to the crap graphics chip ('Black Screen of Death' NVIDIA GeForce GT 330M) on this laptop model, I cannot attach an external monitor.
Clearly, the largest 16:9 aspect ratio video I can natively capture on this screen is 1680 x 945, making the scaling to be applied = 1920 / 1680, or approximately 1.14 times the original.
Not bad, but taking a step back for a moment, am I at the time of recording truly stuck with 1680 x 945 (16:9) max, or are there other options in the pursuit of a 1920 x 1080 end result?

Would (for example) ffmpeg allow original recording at a resolution
larger than the native screen size? (conceivable, as all user interaction is in the middle of the screen, the remainder simply providing visual context).
Can I otherwise trick my laptop into thinking it has a 1920 x 1080 screen attached?
is there some other possibility I should be aware of?

If you see a practical approach to a native 1920 x 1080 recording, some detail (for example ffmpeg command) would be helpful.
Operating System - OS X Yosemite - Version 10.10.5 (14F1021)
Hardware:
MacBook Pro (15-inch, Mid 2010)
Processor 2.8 GHz Intel Core i7
Memory 8 GB 1067 MHz DDR
Graphics Intel HD Graphics 288 MB
NVIDIA GeForce GT 330M

Apparently, it may be possible to get the OS to output a higher resolution than the native one. It requires some config files tweaking. I can't vouch for this method.
If you just need to show, say, the middle third of the screen, then another possibility is to zoom in to provide a larger source for ffmpeg to upscale. Depending on the size of the area of interest, this might not make much difference.
Of course, I dare say, 1680 --> 1920 should be an easy upscale post-recording with hardly much difference in perceptual quality unless your items of interest are very small.

Amongst the Reddit chat (your first paragraph link) is mention of the resolution switching program QuickRes, but on closer examination they issue an explicit warning against changing to HiDPI modes (presumably also relevant to config file tweaking). Given my dodgy graphics chip (single point of failure nightmare), perhaps something I should just respect. The zoom feature, though good to know of, can't compete with direct SVG zooming in a browser. That leaves upscaling, which (Blender willing..) I'm now trying. Test? --> Discrete 1920 x 1080 PC screen.


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How to cut large video without video editing software (Windows)
I have a large video that I need only a small portion of online, and then I want to edit and cut out some parts inside that portion of video online. How do I accomplish that without any special software except perhaps VLC or the likes?
I wary of downloading AVIdemux and other "free" stuff from the web.
I've had bad experience with Softonic, CNet and the likes and even SourceForge who used to be great but then started installing stuff that you can't get rid of, and that affect your system like changing your search page etc. (For some reason many times they are not defined as malware, but in some cases are, and then its even worse because online instructions tell you to download "removal" software which usually like a Trojan just wreaks havoc).
Maybe there's something on GitHub?

A common tool is avidemux. Get it from developer site. Also only careless old people get adware from installers, pay more attention.

Dear @jiggunjer there's nothing wrong with being old. And there is something very wrong with the websites that give you trojanware (they claim that its legit because they give you the option to skip). So if they allow themselves that behavior I cannot trust that what they give as freeware is clean. Not sure about Avidemux itself. Would be nice to hear what other users with knowledge can say what they think of it.
See http://forums.fedoraforum.org/showthread.php?t=232194

I agree with you on both points. I just meant that nowadays most people have enough skill to avoid crapware while getting their freeware. It just takes some practice (also check out sandboxy).

Ooh sandboxy, didn't know about it. Thanks!
Anyways, I would rather avoid going into a minefield and endangering everything.

If you need to make multiple cuts and then join them or edit those cuts, you'll need a video editor to do it efficiently. Try Shotcut.

I also wanted to say I found a way with VLC and youtube together: so I'm answering my own question. (But shotcut seems a legit open source from github, without those virus like programs that you can't get rid of, so thank you @Mulvya) Here's how to do it if you already have VLC downloaded (that one also comes with its trojans):

You set the recording to a specific location (tools / preferences: click on left bar's input / codecs... scroll down to  Files, Record directory or filename, and set that directory.
Now wait for your section of video - if you need several sections record each separately.
Go to recorded sections (they should be with a bit extra unneeded seconds, you'll cut precisely on youtube).
Upload the clips to youtube, then edit one of them. Use the Trim to cut in several locations, then stand on the sections you wish to remove and remove them. You can mix other videos into this one.
If you need the final movie downloaded use http://www.clipconverter.cc/

Just a note, this method might involve 4 transcoding steps (may affect quality). Also not clear what "standing on a section" means.

Recording is 1st. Uploading to Youtube is 2nd. I don't think the editing makes any difference in lossful quality. What's the 4th? If you try the youtube editing you'll easily see what "standing on a section" means.


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H.264 on analog camera
Years ago I bought Vitamin D Video software for videosurveillance, which doesn' support H.264, but only mpeg-4.
Currently I'm using two cheap analog cameras (RCA, PAL) connected to pc through 1 usb Easycap and another usb cheap pinnacle (I could't have 2 Easycap connected at the same time) and cameras transmit video at resolution of 640x480 pixels.
Now that one camera stopped working, I'm looking for a cheap but little better camera. Lot of the cameras I found have these specifications:
Resolution: 1200 TV Lines, Pal: 960x860 pixels
Video Compression Format: H.264
Some are cameras have Resolution: 2MP 1920*1080 (always PAL)
When I add a new camera in Vitamin D Video, I can choose between these resolutions:
QVGA 320x240
VGA 640x480
XGA 1024x768
SXGA 1280x1024
My first doubt is: can also analog camera use H.264 codecs? Isn't it a codec for digital transmission?
Also, having an usb device in the middle, do I have to worry if usb devices support h.264 or do I have to check if Vitamin D Video supports it, or both?
Any links / tutorials are welcome.
Thanks

h.264is a digital video codec . Analogue video must be digitised to use h.264. It's a little unclear what you're asking.

if they are camera with rca connector, is it possible that they use h.264 codec?

The OP has camera(s) feeding an analog signal to a USB capture device which transcodes to MPEG-4 Part 2 video. That transcoded stream is ingested by the surveillance app and processed for security purposes. Apparently, their version doesn't support H.264.

To the OP, looks like Vitamin D, since renamed to Sighthound, supports H.264 since version 2 (and many more cameras). H.264 is not an analog signal standard, so any camera which advertises H.264 will output over HDMI or possibly USB. In which case, the USB adapters aren't required.

Thank you @Mulvya, you solved my doubt about H.264 over analog signals. Unlukily, I bought Vitamin D video licence and this isn't valid for Sighthound, for this reason I'm still using Vitamin.

Here is a good guide to help you understand the compression.
Go Digital, scrap analog. You won't need a computer to handle the cameras or a video encoder.
Buy a cheap Axis camera and download Axis Companion software, then the camera just needs access to the internet and you can view it from anywhere in your smartphone.
You could also buy any other IP camera and get their dedicated software.
I work at Axis, so I do recommend our product line for stability, availability and quality.

If you consider purchasing a new camera then you can buy an IP camera that has native mpeg-4 support. There are plenty of models around and prices are very low. This way you won't need the USB device and your overall configuration will be more robust (less components = less points of potential failure).
Another option of course is to buy an H.264 cam and move from Vitamin D to something that supports H.264. H.264 will usually provide much better video quality per bandwidth.
Yet another option, if the camera is not too far away from the computer and has a fixed lens, is to buy a good USB camera, AFAIU Vitamin D supports web cams, and this too can save you the need for a USB dongle.


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How do I change FPS in a sequence in Adobe Premiere Pro CS6
I imported some images for a LEGO stop motion but the animation is going too fast. When I change FPS to something smaller and export, the video is tiny.
I'm not really sure what I do when I change presets, but following tutorials hasn't paid of in my case.

What are you changing - the FPS of the footage or the sequence?

Umm, sequence I guess. Not sure what's the difference.

When you set the number of frames per second of the sequence, you are describing the rate your rendered footage will playback, whatever that footage may be.  If you have 600 frames and you set the sequence to play 60 frames/sec, you'll get 10 seconds of video.  If you set the sequence to play at 6 frames per second, you'll get 100 seconds of video.  60 frames per second is a speed that players like YouTube (now) accept, but 6 frames per second is not.  So if you render a sequence that's supposed to play at 6 fps, you might create something that most players will not honor.
Instead, set your sequence frames per second to what you actually want to play the video at, likely 24, 25, or 30 fps (but maybe 60 fps or 120 fps if you are part of the HFR vanguard).  Inside the sequence, look at all the little (violet) boxes that represent your individual images (JPG, PNG, TGA, whatever they are).  Select them all, right click, and choose the menu item "Speed/Duration...".  That opens up a dialog box.  Change the 00:00:05:00 default to 00:00:00:02 (or however many frames you expect each image to last).  In the world of stop-motion, it is common to make a movie that plays at 24 fps but in which each image is repeated (so 12 images per 24 frames).  If you didn't do "twelves", then use 00:00:00:01.  Select the box "Ripple Edit, Shifting Trailing Clips" and choose OK.  This will create a tiny, but correct, sequence of images that can then be rendered to play back at a sane speed that all video players (including YouTube) will honor.

When I last tried "Ripple Edit, Shifting Trailing Clips", each frame had a blank space in between it. However that's not what I saw happening in a tutorial. Am I doing something wrong?

The result you describe is what I would expect if you did not select that option.  The whole point of the ripple is to shift the clips as they shrink.

Then why is it happening?

Once you have an error in your project it can be difficult to correct subsequently.  If you have spaces between your clips when you start, you'll have spaces between your clips after you are done.  Try creating a new project, a new sequence, import your images to the project, put them into a bin, make sure they are all in the correct order in the bin, move/copy the bin to your timeline, and verify that all the images are five seconds long with no space between them.  Then follow the above and it should work.

What exactly is a bin? I just CTRL+A my images and drag them onto Video 1.

When you first import your images into the project viewer, you can select all (CTRL+A / ⌘+A) right click and select "New Bin".  The nice thing about a bin is that you can sort items by themselves, so that extraneous items don't get sorted into them.  When you have a bin, which by default is orange, and it's sorted the way you like, you can drag that to the timeline.


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How To Make an Advanced Loading Bar in Sony Vegas
Using Photoshop and Sony Vegas I Have Made a Simple Loading Bar and I Want To Upgrade it. Basically I Want To add a Spark animation To The Top of The Bar That Moves With it until it Loads Completely, I Thought That only Timing Would be The Problem and I could Just use a Push Transition but it doesn't Seem So, Any Ideas?

Can you illustrate or post an image of what the bar with the spark looks like?

Sure, Here is a Picture of The Loading Bar about Halfway, and The Spark Animation Where it Should Be When The Bar is Halfway

Just So That You Know. The Loading Bar is an Image and The Spark is a Video

If the spark footage has an alpha channel, as is likely, then make sure, it is activated - right-click on the event, launch Properties, and check that Alpha Channel in the Media tab is set to Straight.
Now, animate the Spark's position in its Pan-Crop window to track the leading edge of the bar.

Offhand, I don't know if you parent a track, is the parent's Pan/Zoom inherited by the child tracks. Try it out. For Track Motion, it is, but that reduces the resolution of the footage pre-compositing to fit the project dimensions, so I avoid it.


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Configure FreeStyler to work with DMXking ultraDMX RDM Pro/Micro
I have a USB DMX product called DMXking ultraDMX RDM Pro (I've also tried the DMXking ultraDMX Micro, same issue) and I'm using the free software FreeStyler and trying to figure out how to get it to work. These products are for controlling DMX light fixtures.

Select either DMXking USB DMX512-A or Enttec Pro. Do not choose ultraDMX Pro unless you are actually using this device. Also make sure you've selected the right COM port, plus make sure the latest driver from FTDI Chip is installed (FTDI Drivers). A good practice is to use the ultraDMX Configuration Utility to help locate this if necessary. Sometimes FreeStyler gives an error message during device selection, just restart it.


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CRF for 'visually lossless' for libx265
The ffmpeg wiki page for H.264 states that:

Consider 18 (CRF) to be visually lossless or nearly so: it should look the
  same or nearly the same as the input but it isn't technically
  lossless.

Although, while I understand that H.265 is a relatively new codec, are there any general recommended settings to achieve a "visually lossless" encoding using X264 with ffmpeg?
The H.265 wiki page does state:

The CRF of 28 should visually correspond to libx264 video at CRF 23,
  but result in about half the file size.

But from what I've picked up, this scale of equivalents is not the same.
Edit regarding the duplicated question
I am aware of the linked question, however 'visually lossless' strikes me as more of quite a specific thing - i.e. the point where specifying higher quality does not change the final image.
The linked question is asking about equivalent CRF levels to achieve equivalent quality. Although as I've just said, visually lossless would appear to me to be something much more specific than asking 'the equivalent of CRF 18'...

See this question.

The point here is even if the CRF scale of H265 is "different" from the H264 one, H265 developers state that the visually lossless one is again the CRF 18. Considering that the final visual resulting quality of a h265 transcode with same crf of a h264 one is generally greater, if is true that CRF 18 in h264 is visually lossless, the same should go for h265. Said this and if you want go over a descriptional comparison, if you want have mathematical compare the goodness of the various settings you can make your own check with SSIM and PSNR.

They are standard indexes for compare quality rendering of different encodings, useful when you reach levels of quality so close that are impossible to tell visually and they are inside a reply into my original question.

If you are in the mood of testing, you could prepare a big amount of different video types and encode them first in h264 with crf 18, then in h265 with cfr 18 or higher in steps and compare the 2 indexes said above until you find something similar between your 18crf h264 and the h265 files.. but it's something very time consuming and probably someone else already did it ;)


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Smartphone recording distortion
I have a Lumia 950 XL that can record 4k at 30 FPS and 1080p at 60 FPS. Everythings working great, but I'm having the same issues that I've had with my old Samsung smartphone when recording video: when moving, the recording seems to pop in and out. Not sure how to describe it, but it what it seems like is that it's as if my lens were submerged in water and the water is moving in and out of perspective. What is the explanation for this? How do we prevent this from happening?
This seems to happen for quick or jerky movements but not steady ones though.
EDIT: Here's a sample video:

Can you post screenshots? Offhand, it looks like an autofocus issue.

Will do @Mulvya , but in a few hours, but I will also try the autofocus lead and let you know!

@Mulvya added a sample video...I also tried manually setting the focus but it is still the same

Ah, rolling shutter. See https://www.youtube.com/watch?v=DG4OjpD3Zow and https://www.youtube.com/watch?v=mQ0hS7l9ckY

Thanks for the informative and entertaining vids @Mulvya .


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How can I insert a censor bar into a mp4 movie?
I have a feature film in mp4 format. There is one scene where I just want to place a black censor box to conceal one part of the screen, no more than 7 seconds.
I'm a beginner, so my concern is that if I import the two-hour, 700MB file into, say, Windows Movie Maker, make the minor change, and then convert the finished product back into mp4, then the finished file will have a huge size that won't fit on a 4.7GB DVD.
Is that a valid concern? Are there video editing softwares out there that somewhat retain original file size?

Any decent video editing software will allow you to specify bitrate and resolution in export settings. Sony Vegas Pro or Movie Studio, Adobe Premiere Elements, as should Cyberlink Powerdirector among others.
For a 2 hour movie with 700MB as output size, you want a target or average bitrate of 670 kbps for the video and 128 kbps for the audio.

Do you know if those softwares have a feature that will let me insert a censor bar?

They all should. For Vegas, see https://www.youtube.com/watch?v=OuYNWhDUzR4


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What are the pros and cons of a few of Photoshop's video format export options?
I'm outputting a video in Photoshop and there are a wide range of export options with seemingly very few if any blogs or tutorials explaining the pros and cons of the different options. I've researched enough to know that different file types don't necessarily affect quality in themselves, but rather the video codecs they support.
For example I just exported this in AVI mode at 1080p, but have a weird flicker. This isn't really a problem, since I can just export in a different format and get a better result, but I'm just interested in a basic explanations of the pros and cons of a few different formats available in PS.
To go over a range of options I'm talking about:
QuickTime Movie

H.264
Animation
DV - PAL
DV / DVCPRO NTSC
DVCPRO PAL
JPEG 2000
MPEG-4 Video
None
Photo - JPEG
PNG

AVI

Cinepak
DV* options listed above

Cinepak offers some weird options such as "Keyframe every x seconds" and "Limit data rate to x".
H.264 also offers "Keyframes every x seconds", "Frame reordering", and "Limit data rate to x"
Most of them offer a depth and quality setting ranging from low to high or best - I always choose the best quality, but I'm not sure it's necessary.
If someone could very briefly explain the pros and cons of these different compression formats, and their effects on the resulting video, purposes, etc, it'd help a lot. I'd just go through and render different options to see the differences, but this is a complex animation and even with a powerful graphics card the rendering takes 30 minutes to an hour.

The dropbox link is dead

@MoritzLost fixed

You don't need to worry about most of those formats. Over the last decades, different formats have emerged for different purposes. Since most of those purposes still exist somewhere, software such as the Adobe suit still supports most of them, but for general online video purposes, you don't need most of them. For a normal video that is intended to be watched on computers, uploaded to the internet et c., MP4 or AVI videos with the H.264 codec is what you will want to use, as it is supported by virtually all applications and hardware. QuickTime Movie (usually used with .mov files, though the codec can be used in other container formats as well) is another option.

"Keyframe every x seconds"

In the context of encoding an H.264 video, the term 'keyframe' refers to I-frames. For compression purposes, many codecs don't save each individual frame fully. Instead, they save one full frame (similar to one image file) every few seconds (or in irregular intervals) and for all the frames in between, only the difference between the last I-frame (keyframe) is saved, reducing filesize. The keyframe interval controls the frequency of the keyframes. Most encoders can also place them irregularly whenever there is a large difference between two adjacent frames (which usually means a scene change), which is what you want if it is an option and you don't have a special reason why you need to set the keyframe interval manully.

"Limit data rate to x"

Probably refers to the bitrate (I never understood the tendency of different developers to give their settings special names, even though it's the same damn thing every time. Talk about confusing users). The bitrate is the amount of bits (i.e. information) per second. The higher the bitrate, the better the quality (non-linearly though, after a certain point there are diminishing returns in quality increasement). And the higher the bitrate, the larger the resulting file.
Edit: As Mulvya pointed out, this setting probably refers to the maximum bitrate rather than the target bitrate. That is, the encoder will never exceed that average bitrate, it may however use a lower value if feasible. In this case, the quality slider (see next section) would control the target bitrate.

Most of them offer a depth and quality setting ranging from low to high or best - I always choose the best quality, but I'm not sure it's necessary.

Quality sliders usually control the compression level, which in turn is related to the bitrate. Higher bitrate = higher quality = higher filesize. You will have to experiment with that to find a setting where you don't notice any artifacts in the rendered file while the filesize is still acceptable.

For example I just exported this in AVI mode at 1080p, but have a weird flicker.

Looks to me like a framerate issue, but could also be caused by messing with the keyframe interval. As you said, try a different format, preferably MP4/H.264. In general, don't meddle with a setting if you don't know what it does. Setting an unusual keyframe interval for instance can yield unexpected results.

but this is a complex animation and even with a powerful graphics card the rendering takes 30 minutes to an hour

I had to wait about three days for an animation rendering to finish once (blender using cycles engine though), just to put that into perspective °v°

I had to wait about three days for an animation rendering to finish once - the only real reason for having triple 1080s. One day maybe. Then again I'm not sure blender is optimized to utilize 3 GPUs effectively.

Avoid AVI if rendering to H.264. Old container. MP4/MOV/MXF is fine. Limit data rate to x --> this could be the max bitrate, which may be a ceiling useful if the output is to be streamed or played in a hardware player.

@Mulvya Good point, I've edited my answer


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How is a shot like this done? (Smooth angle shift in extreme slow-motion)
https://i.imgur.com/LqzejN9.mp4
How is this achieved? It seems like the camera would have to go from sitting still to moving extremely fast to capture a pan that far to the side while the wave is moving in such incredibly slow motion. Right? If the camera was changing angle at non-insane speeds, its angle change would happen in extreme slow motion just like the environment it seems like to me.
But it's over water in the waves, so it could be a drone but can drones really go from hovering still to instantly moving as fast as necessary for that shot? They could have a boat with a rig to pull the camera sideways fast but it would have to be pretty close considering the angle change and wouldn't it have problems because the waves are bouncing it around?

It might be that, Michael, but it actually looks from some of the morphing that it might be all in the edit rather than multiple cameras. Look at the leading edge of the wave as it goes past the surfer - I think the foreground and background are taken from the video, while the surfer is frozen.

I would have to agree with @Michael on this one, Bullet Time (as the name suggests when opening up the image "Surfing Bullet Time" would probably be the best result. To be fair it was probably filmed on a small boat (cameras in waterproof housings) as take just as the boat goes over the wave (just before it turns over)
Here is the actual video

It was shot with 12 GoPro cameras


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Cutting scene results in choppy transition
I used the Razor tool in Openshot to remove a scene from a movie. However, the transition between the two surrounding scenes is now very choppy. The movie is now simply two separate clips. Is there a way to "fuse" the two clips together, so the transition is smooth?

The two most common approaches, if you don't have B-roll coverage, is either a dissolve (usually a cross-dissolve) or a fade-out/fade-in (usually dip-to-black).  Garish effects (essentially all the others offered in a typical NLE) can also be used (but are usually avoided).
IF the clip you are cutting out means joining what looks like a single take (with a discontinuity in the middle), the dip is your friend.  If the clip you are cutting out takes you from one scene to another, the cross dissolve can also work.  A series of cross-dissolves can work to show the passage of time (where the camera stays fixed and the subject is seen doing on thing, fading into doing another, etc.).

can these functions be found on openshot?

Yes, openshot does have transitions, and they have both dissolves and fades.  They also have a plethora of garish effects if you really want to call attention to the transition instead of letting the story and the video imagery speak for itself.


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FFMPEG Tiff images to losseless video (H265) lags, broken output
I have 226 sequenced images (TIFF, 6.2MB each) and i would like loseless save them like video by using H265.
Here is command which I used:
ffmpeg -f image2 -framerate 25 -i IMG_%03d.tif -vcodec libx265 -x265-params lossless -strict experimental -pix_fmt yuv420p -report movie_newh265yuv420.mp4

And here is output video: Broken Output Video
I really don't know how to fix it. Video should looks like this one Good Video If u have any idea I will be very glad.
Report from FFMPEG below:
Thank you

http://pastebin.com/7sMn1Vye - Report

You have 261 frames but only 226 frames have been encoded. 35 frames are missing. Cycle through the image sequence at slow speed in a image browser and see if the jumps still occur.

My bad, I have 226 frames so all have been encoded. Where is mistake now ? Maybe I should add something specific -x265-params ?

What do the image filenames look like?

IMG_001.tif to IMG_226.tif

Run ffmpeg -f image2 -framerate 25 -i IMG_%03d.tif -vcodec rawvideo -pix_fmt yuv420p raw_newh265yuv420.avi and see if the jumps occur.

The same :/ maybe something wrong with my ffmpeg ?

No. the files seem to be picked out of order. Scan through them manually to check continuity but take care to note the file being scanned.

I made mistake in change name script /facepalm. Now everything it's ok. Sorry mate for my brainless and Thank you so much for your perseverance