text:
Reverse order of clips when importing from card or camera in Final Cut Pro X?
When I'm doing to-camera commentary in my studio, a regular part of my workflow is to record some footage on my DSLR and then import it immediately into Final Cut Pro X. I'll often need another take (or ten) before I've finished so it's really annoying that when FCPX fetches the files it does it in the order they were shot, so the file I want is always the last to appear.

Is there any way to make Final Cut Pro X fetch the most recently recorded file first instead?

I don't think it's possible. In my experience the contents isn't loaded in any particular order, so setting the order to ascending content created date doesn't actually change the order the files are loaded. You can still try setting the date order to ascending if you wish: click the  button on the status bar then click the ‘content created’ header to sort ascending.

Try the other answer first. Just import it, and press the organize button.
Otherwise,
From looking at your picture (book by it's cover analysis):

Where do you get the file name? Ex. PQ9A3..(confusing to ordering program?) (How does the computer supposed to know if it is (0, 1, 2, 3, and 4?)
Try to rename a few of your clips to (0, 1, 2, 3, 4) and see what happens. If the ordering works... you have problems with your filename system.

The computer understands this order for File Explorer:

See if it works on Mac. I usually use Windows, but the concepts should be very similar.


text:
Understanding mpeg-dash for VoD

What programs should I use for create MPEG-DASH stream and generate manifest file [may be ffmpeg but I'm not sure that it is enough]?
Can I add subtitles file after I create stream?
Can I store audio file as another stream and attach it in manifest?

source: Stack Exchange

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

sort: votes


text:
Bitrate Settings for Minimal Data-Loss
I cut clips from high-quality variable bitrate videos. What I'm wondering is if aiming for the same bitrate as the source video would result in a transparent-quality video. For example:
═════
Source video: kmaccaroni.mp4
Bit rate mode               : Variable
Bit rate                    : 26.0 Mb/s
Maximum bit rate            : 37.0 Mb/s
═════
I understand that data-loss is inevitable when transcoding. I simply want to minimize it in a reasonable manner.
•In this case, would it be enough to set my encoder settings to the same bitrate values?
•Would there be any benefit to using the same target rate but 50.0 MB/s for the Maximum rate?
•If not, should I increase the bitrate by a certain amount?
•What do you think of Premiere's "Adaptive High Bitrate" option?
•Is there any meaningful gains if I set the bitrate to 50.0 Mb/s CBR?
Thanks for reading.

What's done with the extracted clips?

The answer is no. You need lossless encoding. The good news is, the file size will be of a reasonable size if you use the H.264 encoder (and also H.265 or VP9, but those are not as popular and widely extended as H.264).
I am not used to that software you mention, but there must be an option called either "H.264" or "MPEG-4 AVC" or "MPEG-4 Part 10" (not to be confused with "MPEG-4 ASP" or "MPEG-4 Part 2" !), with the settings to "lossless" or "Constant Rate Factor equals zero".
Here are the settings in case you are using Blender:

Since you seem to be at the beginning of your learning curve, I recommend you switch to Blender. It is a professional alternative that was released as free software at some point and is maintained and upgraded by a very active and serious community. It is free, and there are awesome tutorials (Google for Mikeycal Meyers in YouTube).
Remark
You want to use lossless encoding only for the intermediate steps (e.g. cutting clips from other videos and putting them together as it seems you are doing). But once you are satisfied with the final form, for practical purposes you want to convert the last lossless compilation to a lossy format, e.g. H.264 with constant rate factor between 18 and 22 for visually good results. I use ffmpeg for this, although it can be done in Blender too.

Mephisto - the rest of your answer is fine, but that final para adds nothing useful, and would be likely to attract downvotes. Please do not post things like that - they are irrelevant to this site.

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


text:
Weird scrolling lines in video while using Akaso EK7000 in low light
I got the Akaso EK7000 action cam in the mail today. The camera works almost perfectly other than one issue I noticed. The issue I noticed is a scrolling line that appears in the video at 4k 25fps. I then took about the same clip in the same conditions at 1080p 60fps and I didn't notice the issue. Here are the clips I took.
4k 25fps:
Video on Vimeo (password: video)
1080p 60fps:
Video in Vimeo (password: video)
Also, the lines on the walls in both clip aren't caused by the camera, they are just shadows from a railing behind me.
I've heard about something called rolling shutter, could this be caused by that at all?

that's the frame rate and electricity frequency
Ill bet if you filmed at 1080 25fps you would get the same result. Im going to assume you are based in the US which uses the standard 30fps which is why your 1080 footage does not show it as 60fps is a multiple of 30fps but 25fps is not which is why you are getting the banding.
Hope that helps
FYI there is nothing you can do in camera unless the 4k offers a 30fps (or multiple of) to avoid the banding when filming with standard household lighting

Well that could still be the same issue. I’ve had it before while filming LED lights that I had to drop to 40fps to remove the flicker. It’s all going to be down to the frequency of the electric in the end. There are quite a few YouTube and blog posts explaining this with examples etc

you probably have already figured it out, but for new guys googling this:
I got the Apexcam 4K 20MP WIFI Action Camera
All I had to do is change the 'Frequency' settings from 50hz to 60hz. That solved most of the problems, only the 1080p 60fps mode still has those lines, don't know what to do about that. All other modes work fine. If your camera has a frequency setting, might work for you, if it doesn't, you might have to limit shooting outside with constant lighting (not artificial sources like streetlamps).

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


text:
How to line up two audio tracks in Premiere Pro?
I understand that I'm down to the frame size on the timeline scale but I need to line these up, otherwise it sounds completely ridiculous. I can't move the two closer together since one overshoots the line-up.

What is the best "bandaid" fix for now?
How can I avoid this problem later? I record audio on two different mics, I need to be able to perfectly line them up.

Audio in Premiere can be aligned by analysing two or more audio files and automatically comparing for similarity.
For the audio recorded on separate microphones, select both clips, right-click and select 'Synchronise'. Select 'Audio' as a synchronize point and press OK.

You can use the Source editor to fine-tune the in and out points to remove any silence before and after the microphone recording.

This feature can be extremely useful for aligning multi-cam footage.

Okay, I was able to find a band-aid quicky fix. The desired audio/video tracks to be synchronized must be unlinked and only one audio track has to be moved separately, then you can match it up to milliseconds. Now, in my case, I make commentary over a video, so my commentary will be simply early or late, depending which track you move, but only by about a frame, which is not a big deal for me - as long as the audio and video are synchronized. If you're making a song or something very "flowy", this will probably not be helpful.


text:
Switching between multiple m3u8 playlist
In a live stream setup, I have 2 cameras and each one sends RTMP stream to one different application which is on my Nginx-RTMP server. On the browser I am using Videojs Hls plugin.
Now my question is how can I load these two streams one after another in the same hlsplayer player instance. For example, I want to load the first 15 seconds in my first source and the next 15 seconds from my second source in the same player. Since the .ts files are named incrementally and if I have 5sec chunks of .ts files in each .m3u8 file, I want to load the first 3 .ts files to be loaded from the first source(.m3u8 file) and the next 3 from another source(.m3u8 file). How can I achieve that?
Can I generate some kind of master M3U8 file which has the list of these other .M3U8 files or can I develop a plugin in videojs to load the appropriate ts files directly?
source1.m3u8
1.ts
2.ts
3.ts
source2.m3u8
1.ts
2.ts
3.ts
I want to load 1.ts from source1.m3u8 and 2.ts from source2.m3u8 but with no delay or lag.

Do you have a solution?

Did you ever work this out?

Switching between multiple HLS streams can be useful in two scenarios:

The typical scenario is multi-bitrate HLS, where you switch between different bitrates and resolutions to accommodate different client bandwidths.
Backup and disaster recovery scenarios, where you switch between two similar HLS streams when one becomes unavailable.

Multiple Resolution HLS
Multi-bitrate HLS cannot be implemented on the streaming server itself. As you mentioned, two HLS .ts files need to be switchable, with the same name and content, to avoid issues like stuttering or image repetition. Multi-bitrate encoding needs to be done at the encoder level, such as using FFmpeg to transcode an RTMP stream into multiple HLS streams with different bitrates:
ffmpeg -f flv -i "rtmp://server/live/livestream" \
  -map 0:v:0 -map 0:a:0 -map 0:v:0 -map 0:a:0 -map 0:v:0 -map 0:a:0 \
  -c:v libx264 -crf 22 -c:a aac -ar 44100 \
  -filter:v:0 scale=w=480:h=360  -maxrate:v:0 600k -b:a:0 500k \
  -filter:v:1 scale=w=640:h=480  -maxrate:v:1 1500k -b:a:1 1000k \
  -filter:v:2 scale=w=1280:h=720 -maxrate:v:2 3000k -b:a:2 2000k \
  -var_stream_map "v:0,a:0,name:360p v:1,a:1,name:480p v:2,a:2,name:720p" \
  -preset fast -hls_list_size 10 -threads 0 -f hls \
  -hls_time 3 -hls_flags independent_segments \
  -master_pl_name "livestream.m3u8" \
  -y "livestream-%v.m3u8"

It will generate a master.m3u8, which contains 3 different m3u8 with different resulutions. You can refer to the detailed explanation in the provided link.
Fault Tolerance HLS
For backup and disaster recovery scenarios, the two HLS streams don't need to be identical. When one HLS stream becomes unavailable, users will likely refresh the encoder. At this point, switching to another HLS stream or providing a manual switch option can achieve fault tolerance.
Additionally, HLS distribution is usually done through a CDN, which inherently provides fault tolerance for an HLS stream. For self-built HLS CDN distribution scenarios, you'll need to handle this yourself. In this case, it's more suitable to have backup and switching at the RTMP level. You can push multiple RTMP streams, choose an available one to generate HLS, and use an FFmpeg script to achieve this:
while TRUE; do
  ffmpeg -re -i rtmp://ip/app/stream1 -c copy -f flv rtmp://ip/app/production;
  ffmpeg -re -i rtmp://ip/app/stream2 -c copy -f flv rtmp://ip/app/production;
  sleep 0.5;
done

It only generate one HLS stream, but switch between different source RTMP stream. For more information, refer to the detailed explanation in this post.


text:
Recording for Youtube: ffmpeg Thread message queue blocked
I was recording screencasts on Ubuntu 16.04 for youtube with my plantronics headset C520-M which worked just nice. I was using ffmpeg successfully.
Now I wanted to add some "live" video explaining things at a whiteboard, to make the video more attractive.
I was planning to record the live view with Logitech HD Pro Webcam C920, which also has builtin microphones that work not that bad. I can not use the headset for sound, since the whiteboard is too far away from the computer... (plus it might look weird).
I was using this command:
ffmpeg -f v4l2 -framerate 25  -video_size 1280x720 -i /dev/video1 \
       -f alsa -ac 2 -thread_queue_size 1024 -i default \
        output.mkv

That always resulted in

[alsa @ 0x69d540] Thread message queue blocking; consider raising the thread_queue_size option (current value: 1024)

The sound then stops at this point for the rest of the recording.
Thus I have a couple of questions:

Why does it happen that the audio queue blocks?
How far should I raise the thread_queue_size?
How can I avoid that the audio queue blocks?
Which audio input should I use - actually I tried all of them an the sound stops at some point.

Thanks for any hints.

Hi, similar problem here, what maximum value for thread_queue_size did you found to work for you?

I have the same issue. I was thought thread_queue_size 1024 is a big number, but I still got that error after about 2 hours streaming


text:
How to enable multi-camera in Premiere *after* I've already made tons of cuts
I started with an hour-long video interview and cut it down into a 4-minute sequence of clips using Adobe Premiere Pro CC 2017.
Then I remembered that I had a 2nd camera's video file.
How can I convert my sequence to a "multicam" sequence even though I've already cut it up a bunch?
I want to sync up that 2nd video file so that all of the cuts are the same and that I'm then able to simply bounce between 2 camera angles throughout my 4 minutes of cuts.

Ryan, sorry, but I think it's basically too late. You can certainly turn on multicam editing mode now but Premiere is not going to recognize your existing edits. If you have more footage to edit you could use multicam mode for the remaining portion.

Thanks, @David. I've suspected that. But I'm still hoping we're wrong! :-)


text:
FFMPEG dropping the first two frames of segments generated through seeking
I'm trying to script-cut a 24 fps video and it gets close to the right thing, except for two missing frames at the beginning of every segment I cut with seeking.
I've found out that index-frames (keyframes) could become an issue for seeking, so I first create an intermediate file with every frame as a index frame using this line:
ffmpeg -i input.mov -c:v libx264 -g 1 -c:a copy intermediate.mp4
Then I proceed to make a cut with this line. Notice I'm drawing some text on top of it:
ffmpeg -hide_banner -y -i intermediate.mp4 -ss 00:00:02.083333333333 -to 00:00:02.875000000000 -vf drawtext=fontfile=DroidSans.ttf:fontsize=48:text="segment2":fontcolor=yellow:box=1:boxborderw=16:boxcolor=black@0.5:x=w/32:y=h/18 output.mp4

No matter the length of the segment, the first two frames get dropped.
I'm using python do control ffmpeg.
Any ideas?

Edit:
Running ffprobe on one of the generated segments with ffprobe -hide_banner Nixing_0010_0010.mp4 says the following:
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'Nixing_0010_0010.mp4':
Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf57.82.101
  Duration: 00:00:02.11, start: 0.000000, bitrate: 4717 kb/s
    Stream #0:0(eng): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], 4751 kb/s, 24 fps, 24 tbr, 12288 tbn, 48 tbc (default)
    Metadata:
      handler_name    : VideoHandler
      timecode        : 00:00:00:00
    Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 2 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
    Stream #0:2(eng): Data: none (tmcd / 0x64636D74), 0 kb/s
    Metadata:
      handler_name    : TimeCodeHandler
      timecode        : 00:00:00:00


text:
News media copyright?
As a producer I know that samples need to be cleared. How are news programs treated for inclusion in musical works. Are some historical works public domain (Kennedy moon mission speech is a good example). What about current news, NPR, etc?

Are you trying to ask if you can include a portion of a newscast within a musical work without paying royalties? If so, that depends on where you are from and the interpretation of the fair use criteria there.

Yes, that's the thing. In US, I am trying to learn more about this. Several people I work with have had this question. I understand how musical sampling goes, but wasn't sure if there were different rules for news media since news is constantly regurgitated and referenced.

In the US, fair use, the doctrine of copyright law that permits limited use of copyrighted material without needing to obtain permission first, is measured by four criteria. It doesn't matter whether the work you are including or creating is music, text, or a newscast, the same four criteria apply.

The purpose and character of the work you are including the copyrighted material in. For example, are you using it for educational purposes or are you trying to profit from what you are making?
The nature of the material you are including.
The amount of the work you are including, in relative and absolute terms. Are you including 5 seconds of a 1 hour work or all 10 lines of a poem?
The effect on the market or value of the included work. Are you going to take sales away from the included work?

However, there is no checklist to determine if your use of something falls under fair use. There is no guarantee that if you are, for example, using 30 seconds of a newscast for for educational purposes that will have no impact on the broadcaster's ability to sell commercials that you fall under fair use. Or that you tip the scale at 31 seconds of included material. Or that any commercial purpose of your work isn't fair use. "The only way to get a definitive answer on whether a particular use is a fair use is to have it resolved in federal court."
Historical material is not automatically public domain nor is it automatically available for fair use. Figuring out if a work's copyright is still in force is rather complex. You need to sort through the correct copyright term for the original work and whether any extensions have been applied.
However, any U.S. government work is automatically in the public domain. But there are exceptions to that. You can't just assume that because you found it on a government website that it is a government work. Something, like an NPR broadcast or a medical study, does not automatically become a government work and public domain just because it is partly or fully funded by the federal government.


text:
Is footage recorded through external recorder really better?
Most DSLRs offer 8-bit recording, 4:2:0 with 100mb/s 50/mb/s 500mb/s in their own containers.
Why would shooting with an external recorder (let's say ProRes HQ or 422), make the picture look better or easier to grade?
Amount of mb/s difference is huge between internal and external.
Still did not get an external recorder, but before I do, would like to get a clear understanding of this. Of course, bigger LCD and lots of SSD space is a huge plus.

Really depends on the camera. What camera are you using?

sony fs7, fs5, a7sii, a7rii, canon mk IV.

Unless the DSLR/Mirrorless camera you are using outputs 10-bit 4:2:2, using an external recorder to up-convert the footage to ProRes HQ will not result in a better image quality than what the camera is able to produce/output.
If anything it will allow you to edit and re-compress the footage multiple times without losing the original quality.
Using an external recorder may result in a better picture quality compared to the internal encoding, because there is more bitrate available per frame, more robust codecs, and also being able to remove the 5, 15, or 30 minutes recording limitation the camera may have.
A bigger plus using an external recorder (or display) is the ability to nail the focus, assess proper exposure, and having multiple eyes monitoring the recording.


text:
What output video format for Kazam requires less cpu power?
Please tell me what is the appropriate StackExchange site to post this question if it doesn't fit here.
I use Kazam to capture my videoconferences. It gets too CPU-demanding but the program is awesome so it doesn't crash but drop frames instead, so that the final video may have 1 frame per second in the most difficult moments but with an uninterrupted sound and full correct images.
Which one of these output formats for the video will be less demanding for the program, so that the frame rate does not drop to such low values? I don't mind a big file size, I can compress the video later. Here are the options:
VP8 in webm container,
H.264 in MP4,
RAW video in AVI,
HUFFYUV (no darn idea what this is) in AVI,
Lossless JPEG in AVI.

VP8 and H.264 should essentially be the same demand due to them being similar.
RAW is well, RAW, each specific pixel data, with no methods of reducing file space, this can cause very large file sizes, but is in theory the least intensive as long as your hard drive can record fast enough.
HUFFYUV is basically the same as RAW, however it uses some methods to reduce file size. Depending on the footage it can be about half the size, or even up to 1/10th the size of RAW.
Lossless JPEG, I believe is similar to HUFFYUV, however I don't personally use either of these lossless codecs.
I don't know if Kazam allows you to use custom codecs, but if it does, I highly recommend using the Lagarith Lossless Codec. It's what I personally use, and it has some basic GPU support, very nice file sizes without any loss in quality, and doesn't require any tinkering which some lossless codecs do.


text:
Template based video storage / online programmatic video editing tool?
Is it any template based video format? Wants to create an animation video able to use for Facebook ads. Aim is to do direct marketing with videos, so video content is based on the target audience. The video is composition of a template, static background, and some photos that are moving in the video. Video needs to render for different advertisement with different photo set. Is it possible somehow? Is it a format i.e. I put template video and photos in one folder and when "starting" video, video "loads" photos in? Or I need to use an online / cloud based video editing tool which allows programmatic video edition?

I would think that you could script this using ffmpeg See this related post: https://stackoverflow.com/questions/45869889/ffmpeg-move-overlay-from-point-a-to-b-to-c-to-d

As well as @ElderGeek's suggestion of ffmpeg, Adobe After effects can be used to generate bespoke video for the web. It can be fully scripted using Adobe's extendscript on the server and run as a headless process. You can thus programmatically create video templates and alter such things as text, image content, or insert clips, then render and deliver.
Note that the rendering does take time and CPU (for both ffmpeg and AE). To achieve real-time customisation you may want to consider using the HTML canvas element, which can support video and animation, working on the client side.


text:
How to use ffmpeg to fade in/out a veriable frame rate video clip with unknown duration
I have been looking for a way to use ffmpeg to downscale some MPEG-4 (Base Media / Version 2) video files recorded with a variable frame rate, adding fade in/out effects at the head and tail of each clip.
Based on the answer provided here, I've been using the following command line to add a 2 second fade/out effect on to my clips:
ffmpeg -i VID_1.mp4 -sseof -2 -copyts -i VID_1.mp4 -lavfi "[1]fade=out:s=0:d=2[tail];[0][tail]overlay,fade=in:s=0:d=2[overlay]; anullsrc,atrim=0:4[audiotail];[0][audiotail]acrossfade=d=2,afade=d=2[audio];[overlay]scale=640:-1[video]" -map "[video]" -map "[audio]" -vsync 2 -sws_flags gauss -c:v libx264 -crf 18 -preset slow -shortest -report -hide_banner VID_1_out.mp4

My questions:

I seem to get a lot of the following error lines in the report

cur_dts is invalid (this is harmless if it occurs once at the start per stream)
Is it normal?

In the resulting output video clip, the fade-in comes out less than 2 seconds (about 1 second), and there appears no fade out, just a black-out for the last four seconds. Where is my command line wrong?
The duration of the original clip is 24s640ms, the output file is longer by 2s022ms. Why additional 22 ms?

If I drop the -vsync 2 option, the output clip frame rate becomes exactly the same as that of the source video file. This, however doesn't deal away with the above issues.

Share your file.

link - the original video clip; link - the log file created by ffmpeg; link - the ffmpeg version used

Can't download video file - file access error.

There is no password set, so all of the three files should be readily available for download. The link to the video file is https://filebin.ca/3qaIGfKJdhBs/VID_1.zip

Or this link https://www.sendspace.com/file/h47mib

This works here
ffmpeg -i VID_1.mp4 -sseof -2 -copyts -i VID_1.mp4 -lavfi "[1]fade=out:s=1:d=2[tail];[0][tail]overlay,fade=in:s=0:d=2,scale=640:-2[video];anullsrc,atrim=0:2.1[audiotail];[0][audiotail]acrossfade=d=2,afade=d=2[audio]" -map "[video]" -map "[audio]" -vsync 2 -sws_flags gauss -c:v libx264 -crf 18 -preset slow -shortest -report VID_1_out.mp4

With some videos, usually those with variable FPS, the fade filter only works with start frame as non-zero. Also, the anullsrc needs to be only slightly greater than the crossfade duration.


text:
Sound and image are shifted after importing them into Adobe Premiere
Even if it isn't the case on the IPhone and when reading it on my Windows 10, my .MOV file has its sound and image shifted on Adobe Premiere. I can manipulate the sound regardless of the video but do you have any better idea than faire du bricolage ?

If you recorded using the IPhone, it could be due to the fact that the camera records in a variable frame-rate or VFR. This means that if the camera can't record a frame, it will skip it and so that second will have 59 instead of 60, and sometimes this can be very bad for longer footage and older phones. After time it those skipped frames will add up.
Adobe programs don't like variable frame-rates, I believe this is because they are "Professional" and don't think they need to support this feature because it's only a problem with low level cameras and recording software. They intend all footage to be Constant Frame Rate or CFR, meaning there is no skipped frames at all. When it comes into contact with VFR they essentially stretch out the footage and frames to fit the entire footage time, while keeping it at a CFR.
I personally don't know any amazing way of fixing this, other than re-compressing it using a program like Handbrake. Using handbrake you can change the footage frame-rate to a CFR. Handbrake is my solution, however it only supports H.264 and H.265, etc so it can be limiting. If you want to make sure you don't lose quality, try finding a different program and rendering it with a lossless codec.

Thank you for this well documented answer
Unfortunately it seems that Handbrake doesn't recognize .MOV videos


text:
Premiere writes the text in the wrong side
I'm trying to write a title on a video but Premiere writes in in the wrong side : from right to left. Let me show you, when I try to write HR, I have  RH

And when I add "&AI" I got "&AI".

Can you help me writting it in the left to right side, that is to say to have "HR&AI" ?

Check under your Preferences in the 'Graphics' section that the 'Default Paragraph Dirction' is not right-to-left.
After adjusting the setting, you may need to create a new text layer to see the changes take place.


text:
Create a perfect square mask on a graphic clip
I have a square graphic created with the rectangle tool (holding shift to create a perfect square).
I need to mask this square with a square shaped mask.
After clicking on the rectangle mask button in the Effect Controls panel, a rectangle mask was created for me, however I want a perfect square.

I can't see any way to turn this rectangle mask into a square mask beyond moving the points and "eyeballing" it, which I do not want to do.
I've grown increasingly frustrated with the masking system because it seems like it lacks basic features, however my fingers are crossed that I'm actually just missing something obvious.
Thanks for your time!

You're not the only one frustrated with Premieres masking/shape tools so don't worry.

That makes me worried


text:
ffmpeg - Problem with zoompan
I'm trying to create a video from a set of images, adding texts to each image that slide from one side to the center ( one left to right, another right to left ), with fading between each videos ( not between text but between video ).
Actually I have this code that generare a simple video, with text sliding and fade:
ffmpeg -y \
    -loop 1 -t 10 -i img001.jpg  \
    -loop 1 -t 10 -i img002.jpg  \
-filter_complex \
"\
[0:v]\
drawtext=fontfile='IndieFlower.ttf':enable='between(t,0,5)':\
text='Caption 1 Scena 1':\
fontsize=60:fontcolor=white:\
x=t*300*lte(t*300\,(w-text_w)/2)+(w-text_w)/2*gt(t*300\,(w-text_w)/2):y=h-line_h-10:\
shadowx=3:shadowy=3:shadowcolor=black:\
boxborderw=10:box=1:boxcolor=red@0.8,\
drawtext=fontfile='IndieFlower.ttf':enable='between(t,5,10)':\
text='Caption 2 Scena 1':\
fontsize=60:fontcolor=white:\
x=(w-(t-5)*500)*gt(w-(t-5)*500\,(w-text_w)/2)+(w-text_w)/2*lte(w-(t-5)*500\,(w-text_w)/2):y=h-line_h-10:\
shadowx=3:shadowy=3:shadowcolor=black:\
boxborderw=10:box=1:boxcolor=red@0.8\
[final1];\
[1:v]\
fade=t=in:st=0:d=1,\
drawtext=fontfile='IndieFlower.ttf':enable='between(t,0,5)':\
text='Caption 1 Scena 2':\
fontsize=60:fontcolor=red:\
x=t*300*lte(t*300\,(w-text_w)/2)+(w-text_w)/2*gt(t*300\,(w-text_w)/2):y=h-line_h-10:\
shadowx=3:shadowy=3:shadowcolor=white:\
boxborderw=10:box=1:boxcolor=black@0.8,\
drawtext=fontfile='IndieFlower.ttf':enable='between(t,5,10)':\
text='Caption 2 Scena 2':\
fontsize=60:fontcolor=red:\
x=(w-(t-5)*500)*gt(w-(t-5)*500\,(w-text_w)/2)+(w-text_w)/2*lte(w-(t-5)*500\,(w-text_w)/2):y=h-line_h-10:\
shadowx=3:shadowy=3:shadowcolor=white:\
boxborderw=10:box=1:boxcolor=black@0.8\
[final2];\
[final1][final2]concat[final]
" \
-pix_fmt yuvj422p -t 20 -map '[final]' o.mp4

It works well, but now, I'd like to add a zoompan effect to both of the images; so I change the code as follow:
[0:v]\
format=yuvj422p,
scale=iw*10:ih*10,\
zoompan=z='min(zoom+0.0015,1.5)':d=500:x='iw/2-(iw/zoom/2)':y='ih/2 (ih/zoom/2)':s=640x480,\
drawtext=fontfile='IndieFlower.ttf':enable='between(t,0,5)':\

...

[1:v]\
format=yuvj422p,
scale=iw*10:ih*10, \
zoompan=z='min(zoom+0.0015,1.5)':d=500:x='iw/2-(iw/zoom/2)':y='ih/2-(ih/zoom/2)':s=640x480,\
fade=t=in:st=0:d=1,\
...

but this does not work; in the final video there is only the first "video", with the zoompan, the second video does not appear at all!
What I'm doing wrong? I'd like to create a simple zoompan between two video.

zoompan is a weirdly designed filter. It operates on individual frames, whereas most filters operate on a sequence of pictures, whether they are fed from a video file or an image sequence. pzoom should be used for a looped image, and frame sequence generation should be stopped by making d=1.
Change to
zoompan=z='min(pzoom+0.0015,1.5)':d=1:x='iw/2-(iw/zoom/2)':y='ih/2 (ih/zoom/2)':s=640x480

This will fix the zoompan.

Thanks! It works! Really Thanks! I just have these messages:
[swscaler @ 0x7f3d60016880] deprecated pixel format used, make sure you did set range correctly, I'm using -pix_fmt yuvj422p, is not correct?

For final output, yuv420p is standard.

Thanks, it works. To finish my job, I need to add an mp3 to the process. Should I open a new Ask Question, or you can suggest me how to add this new input to the command above? I tryed adding [final1][final2][2:0]concat=n=2:v=1:a=1[finalVideo][finalAudio] but it does not work ( mp3 is the third input )

You don't need to add the audio to the concat. Remove the -map [final]


text:
Maya Python: worldspace to screenspace coordinates
I'd like to convert a worldspace position (x,y,z) to screenspace coordinates (x,y) from the selected camera point of view. I'm a bit limited by the fact I can't load extra modules (e.g. numpy). Is there an affordable way to do this?

Why can't you load other modules?

Not allowed to manage my computer and add extra modules...

I finally found how to do this on the internet. Just call this procedure with a camera name and the worldspace coordinate of a point as attributes.
def worldSpaceToScreenSpace(camera, worldPoint):

    # get current resolution
    resWidth = mc.getAttr('defaultResolution.width')
    resHeight = mc.getAttr('defaultResolution.height')

    # get the dagPath to the camera shape node to get the world inverse matrix
    selList = om.MSelectionList()
    selList.add(camera)
    dagPath = om.MDagPath()
    selList.getDagPath(0,dagPath)
    dagPath.extendToShape()
    camInvMtx = dagPath.inclusiveMatrix().inverse()

    # use a camera function set to get projection matrix, convert the MFloatMatrix
    # into a MMatrix for multiplication compatibility
    fnCam = om.MFnCamera(dagPath)
    mFloatMtx = fnCam.projectionMatrix()
    projMtx = om.MMatrix(mFloatMtx.matrix)

    # multiply all together and do the normalisation
    mPoint = om.MPoint(worldPoint[0],worldPoint[1],worldPoint[2]) * camInvMtx * projMtx;
    x = (mPoint[0] / mPoint[3] / 2 + .5) * resWidth
    y = (mPoint[1] / mPoint[3] / 2 + .5) * resHeight

    return [x,y]


text:
Flash CS6's "Export as AVI" creates lines and squares on my export
Is there a way to have this not happen?
This also happens on MOV exports.


text:
ffmpeg - Building video with audio in loop
I'm building a video from 3 ( or more ) images, with some effects and with an mp3 in background; my issue  is that the mp3 can be shorter than the final video ( whose length dependes from the number of images ) ; is there a way to send audio background in loop, so that when it finish, it restarts and I have no silence during video?
Thanks in advance!
This is the code:
#/bin/bash
ffmpeg -y \
-loop 1 -t 10 -i     img001.jpg  \
-loop 1 -t 10 -i     img002.jpg  \
-loop 1 -t 10 -i     img003.jpg  \
-i 1.mp3  \
-filter_complex \
"\
[0:v]\
format=yuv420p,\
scale=iw*10:ih*10,\
zoompan=z='min(pzoom+0.0015,1.5)':d=1:x='iw/2-(iw/zoom/2)':y='ih/2-(ih/    zoom/2)':s=640x480,\
drawtext=fontfile='IndieFlower.ttf':enable='between(    t,0,5)':\
text='Caption 1 Scena 1':\
fontsize=60:fontcolor=whit    e:\
x=t*300*lte(t*300\,(w-text_w)/2)+(w-text_w)/2*gt(t*300\,(w-t    ext_w)/2):y=h-line_h-10:\
shadowx=3:shadowy=3:shadow    color=black:\
boxborderw=10:box=1:boxcol    or=red@0.8,\
drawtext=fontfile='IndieFlower.ttf':enable='between(    t,5,10)':\
text='Caption 2 Scena 1':\
fontsize=60:fontcolor=whit    e:\
x=(w-(t-5)*500)*gt(w-(t-5)*500\,(w-text_w)/2)+(w-text_w)/2*lte(w-(t-5)*500\,(w-text_w)/2):y=    h-line_h-10:\
shadowx=3:shadowy=3:shadow    color=black:\
boxborderw=10:box=1:boxcol    or=red@0.8,\
fifo\
[final1];\
[1:v]\
format=yuv420p,\
scale=iw*10:ih*10,\
zoompan=z='min(pzoom+0.0015,1.5)':d=1:x='iw/2-(iw/zoom/2)':y='ih/2-(ih/    zoom/2)':s=640x480,\
fade=t=in:st=0:d=1,\
drawtext=fontfile='IndieFlower.ttf':enable='between(    t,0,5)':\
text='Caption 1 Scena 2':\
fontsize=60:fontcolor=red:    \
x=t*300*lte(t*300\,(w-text_w)/2)+(w-text_w)/2*gt(t*300\,(w-t    ext_w)/2):y=h-line_h-10:\
shadowx=3:shadowy=3:shadow    color=white:\
boxborderw=10:box=1:boxcol    or=black@0.8,\
drawtext=fontfile='IndieFlower.ttf':enable='between(    t,5,10)':\
text='Caption 2 Scena 2':\
fontsize=60:fontcolor=red:    \
x=(w-(t-5)*500)*gt(w-(t-5)*500\,(w-text_w)/2)+(w-text_w)/2*lte(w-(t-5)*500\,(w-text_w)/2):y=    h-line_h-10:\
shadowx=3:shadowy=3:shadow    color=white:\
boxborderw=10:box=1:boxcol    or=black@0.8,\
fifo\
[final2];\
[2:v]\
format=yuv420p,\
scale=iw*10:ih*10,\
zoompan=z='min(pzoom+0.0015,1.5)':d=1:x='iw/2-(iw/zoom/2)':y='ih/2-(ih/    zoom/2)':s=640x480,\
fade=t=in:st=0:d=1,\
drawtext=fontfile='IndieFlower.ttf':enable='between(    t,0,5)':\
text='Caption 1 Scena 3':\
fontsize=60:fontcolor=red:    \
x=t*300*lte(t*300\,(w-text_w)/2)+(w-text_w)/2*gt(t*300\,(w-t    ext_w)/2):y=h-line_h-10:\
shadowx=3:shadowy=3:shadow    color=white:\
boxborderw=10:box=1:boxcol    or=black@0.8,\
drawtext=fontfile='IndieFlower.ttf':enable='between(    t,5,10)':\
text='Caption 2 Scena 3':\
fontsize=60:fontcolor=red:    \
x=(w-(t-5)*500)*gt(w-(t-5)*500\,(w-text_w)/2)+(w-text_w)/2*lte(w-(t-5)*500\,(w-text_w)/2):y=    h-line_h-10:\
shadowx=3:shadowy=3:shadow    color=white:\
boxborderw=10:box=1:boxcol    or=black@0.8,\
fifo\
[final3];\
[final1][final2][final3]    concat=n=3:v=1:a=0\
" \
-c:v libx264 \
-r 25 \
-pix_fmt yuv420p \
-t 30 \
o.mp4

Set the audio to loop,
-stream_loop -1 -i 1.mp3  \

If you don't set a duration limit like -t 30 \, add
-fflags +shortest -max_interleave_delta 50000

mm I have added -stream_loop -1 -i 1.mp3  to my command; apparently it does not work well. When I reproduce the final video ( its duration is 30 seconds ), the audio ( its duration is 12 seconds ) is not in loop, and, another strange thing, the timing of the video stops at 12 seconds ( the duration of the audio )... Thanks

What build are you using?

16:11 $ ffmpeg -version ffmpeg version 3.2.4-1build2 Copyright (c) 2000-2017 the FFmpeg developers built with gcc 6.3.0 (Ubuntu 6.3.0-8ubuntu1) 20170221

Get the latest git binary. stream_loop had a bug, recently fixed.

I'll update my ffmpeg version and I'll try! Thanks in advance!

this worked in a stream too, thanks !


text:
How to Replicate a Color in Final Cut Pro X
I am editing video in Final Cut Pro X.  Within a video, I would like to create a title that uses a font color that matches a color within the video itself.  How do I do that?

The key thing to realize is that double-clicking the text color within the Inspector brings up a separate color wheel window which contains an eyedropper.  Dragging the eyedropper to the color of interest within the video is how the color gets chosen for the title.
Here's a video on how to replicate a color within Final Cut Pro X.


text:
Does the HDMI output of a Nikon D750 use HDCP?
I need to capture live video (1280x720-60 fps) from a Nikon D750, with a capture card that does not support HDCP signal. The capture card is equipped with a classic HDMI input, while the Nikon comes with a mini-HDMI output. To capture the video, with the capture card, using the classic HDMI cable, I have to use a mini HDMI-HDMI adapter.
Does the Nikon D750 use HDCP on its outputs (mini-HDMI)? If Nikon does not use HDCP, using the adapter, can it create HDCP?

A mini-HDMI to HDMI adapter will not impact the presence of HDCP on the signal, it merely changes the connector passively.  As to whether your Nikon uses HDCP or not, I'm unsure.  My Canon 5D Mark iii also uses a mini-HDMI output and the first couple cables and adapters I got didn't connect very reliably, so I had signal issues until I found a cable that worked well.
You may be having a similar problem to this or it could be HDCP causing issues.  I'd recommend two things you can try in order to troubleshoot this issue.  First, try connecting a known HDCP signal, such as a bluray player to your capture card and see what happens.  It may simply give no signal or it may give an error.  If it gives an error, then you will know that your camera is simply not connecting (unless you get the same error about HDCP being present).
If this is inconclusive, you could also try connecting the camera to a TV that supports HDCP or connecting another mini-HDMI device to the capture device and see if either of those situations work.
It is possible that Nikon may have actually included HDCP in an anti-consumer move intended to prevent use of DSLRs for high end video production, but this seems like an odd choice for them as they have no product in that market segment.  (HDCP would allow connecting to TVs, but prevent use in recording and most video mixers for event production.)

Let us continue this discussion in chat.


text:
What do the options "full chroma interpolation" and "full chroma input" do in video scaling? [ffmpeg]
In ffmpeg, there are options full_chroma_int and full_chroma_inp that can be passed to the video scaling filter. These options are sometimes present in command line examples for the resizing filter, such as in FFmpeg Wiki: Scaling.
The documentation just describes these options as "Enable full chroma interpolation." and "Select full chroma input." respectively. However, it is not clear to me what these options are for and how they affect quality or encoding time.
Does anyone have an intuitive explanation and/or a rule of thumb when to use these options?

I'm guessing that full chroma interpolation means no chroma subsampling, i.e. use yuv444 rather than yuv420 etc.


text:
What codec to use for fastest playback
I want to encode many little 10s-videos in 720p. As I want to play them in a big matrix (6 by 6 videos) in chrome, I am wondering what codec / encoding to use so that the stress on my cpu/gpu is as low as possible when playing them back. I want playback to be as smooth as possible. I don't care for the specific format, audio or filesize.
4 by 4 plays back fine but at 6 by 6 it becomes a bit stuttering.

Are you positive that it isn't getting the file that is bottlenecking?

Do you mean that my harddisk-drive isnt fast enough? I preplay them to make sure they are all in memory. My usages all seem fine, just my cpu is getting high

Okay, that should mean that it comes down to the CPU. An answer wil be hard to get, though: We know nothing about your exact setup (is this project only for you or should everyone have access to it later on [meaning we cannot tell what hardware they will use]? What CPU, what GPU, what drives are you using? What codec and which settings are you using at the moment? Is downsizing an option, as 61280x6720 is quite large?)

Thanks for your feedback! It's just for my machine. I've got an i5-6500 and Radeon R9 380. I tried VP9/webm and h264/mp4. Downsizing might be an option: what I am doing is, is that I'm playing more and more videos over time. So I have 1 by 1, then 2 by 2 and so on. So some videos are getting more or less fullscreened, but yeah. The others can be much smaller as they are downscaled anyway to fit on screen.

This is getting quite confusing (at least to me). Can you provide your ffmpeg code and perhaps a crude schematic drawing of what the output should look like? I first thought that you wanted to have 36 equally (static) sized videos, but your last comment (So some videos are getting more or less fullscreened) does not sound like that...Oh, and also: Chrome as playback engine is a must, right? because I would guess that VLC or other players will be less limited when it comes to formats (e.g. ProRes/DNxHD,...)

6x720p is very large - why not encode smaller?

I'd say your encoding settings are going to be more crucial, given you're limited to the codecs that Chrome can play. Unless I'm wrong you can only use MP4 / h.264 and WebM / VP8 unless you install plugins.
Try lowering the profile of your mp4, e.g. encode using baseline profile. That will mean less compression–so larger files for the same quality or lower quality at the same size–but it reduces the processing power needed to display it.
It is worth noting that there are more hardware decoders commonly available for h.264 encoded video than there are for vp8, meaning that it's more likely to be handled at the hardware level than vp8.

One problem, though: If OP has to save the files to a hard drive (not solid state drive), then they will be limited to around 100 MiB/s = ~ 800 Mb/s tops. With 36*720p files that are not compressed too well, things could get choppy fast.

true. You'd really have to experiment to find the sweet spot between processor bottlenecks and hard drive bottlenecks


text:
What software is recommended for videos like these?
What software should I use for making the color grading like in this video and the slow motion.

Im going to give you a pretty simple answer here.
ANY modern NLE will be able to do this. Your other option is shoot it all in camera and then just touch up a little in you NLE


text:
Collaborative editing network storage workflow
We got to the point where multiple editors working alone can no longer effectively tackle certain projects and move towards collaborative editing (and entire production) seems like a good idea. However, I have zero experience with something like that.
The situation is that we have two geographically separate locations, on each of those locations there are multiple people who would need to collaborate. My idea is that we would have some sort of data server on each location, all of the media would be stored there and those two servers would sync from time to time over the internet (every night or something like that). Is that possible?
Another part then is the local level. I have noticed there are specialized storage solutions, usually very expensive or without publicly available price (so very very expensive I guess). Is there some advantage to those over let's say some Synology RAID network storage connected via 10G ethernet?
Last part of that is, should the editing itself happen on the storage, or is usual practice something like mirroring the project folder to local SSD and editing on that? I want to employ proxies (have Premiere ingest data into project folder on the server and generate proxies on ingest), but I have no idea if that will curb the data size enough to make it viable for editors to have media from the network location on the timeline. Possibly I would imagine (and that might be just my wild dream) to see mounted network drive on my PC and be able to use everything from the network storage, but being able to cache selected project folders locally on a fast SSD.
Thanks ahead for any input!

You need to be more specific. Any workflow is possible given the time and budget. Yes, different storage systems have advantages and disadvantages for different situations. I'd recommend breaking this question up into several that are much more specific with a lot more details, especially on what your budget and specific situation is.


text:
Hebrew subtitles issue on Avid
There is a weird character showing up on the beginning of each subtitle line on Avid even though the srt is “fine” and said character doesn’t show up on movie players... I’m kinda lost, could it be some Avid charset setting or a RTL language issue etc?


text:
ffmpeg- dynamic drawbox
I'd like to apply a dynamic drawbox before a drawtext, for example, with a fixed Y , X and H but with a dynamic W.
This is a trivial example:
/usr/bin/ffmpeg -y -loop 1 -t 5 -i img001.jpg -vf drawbox=x=0:y=0:w=t*300:h=100:color=red@0.5 -y out.mp4

I expect to see a rectangle with the base width that increase with the time; it does not work, the box width is alwais fixed.
Is it possible to create a dynamic drawbox? if not, is there an alternative?

drawbox doesn't support time reference. What are you trying to do?

mmm I'd like to draw a rectangular shape, with some opacity,  that comes from one side and fill the entire witdh of the video. Then the text appear over it, from one side for example. A kind of graphic  introduction for the text.

Since drawbox doesn't support time reference, you need to use a workaround
ffmpeg -y -loop 1 -t 5 -i img001.jpg
  -filter_complex "color=red@0.5:s=Wx100[c];
                   [0][c]overlay='-W+300*t':0"
  -y out.mp4

A color source is created equal to the final size of the box you wanted to draw i.e. image width (W) x 100. Then it is overlaid on the image and animated so that it starts revealing at the rate of 300*t.

It Works! I just did this modification to avoid the rectangle to "go away" from the screen heheh
/usr/bin/ffmpeg -y -loop 1 -t 5 -i source/img001.jpg -filter_complex  "color=red@0.5:s=1024x100[c];[0][c]overlay='if(lte(-1024+1500*t,0),-1024+1500*t,0)':0" -t 10 out.mp4


text:
convert a normal video file into an SBS video in ffmpeg
I am looking to convert a file with ffmpeg into a side-by-side video without cropping or resizing. can you give me an example?


text:
Compact Camera for nighttime live streaming?
We recently adopted a pet hamster for our office, and are interested in setting up a live feed for evenings and weekends so that employees and customers can tune in to the lil guy during his most active hours, and so we can additionally make sure he's doing alright when there are not as many people in the office to check up on him.
We'd be working with close quarters here - he's in a plastic DIY hamster cage that measures 12.62 inches (H) x 18.75 inches (W) x 34.62 inches (L). Because the plastic is not 100% clear the camera would need to be mounted inside the lid of the enclosure, in a corner. We need a fairly small camera as a result, just to ensure he can't climb up to it and chew on it. (It's a dwarf hamster though, so as long as it's a few inches off of the bottom of the enclosure that should be fine... he's short!) If need be, we could probably make a hole in the enclosure for the lens to peek through, but I'd like to avoid that.
The cage currently isn't terribly close to an ethernet switch, so WiFi would be ideal, but the cage could likely be moved to be connected to either my extra Linux box via USB or directly to ethernet. I would then be running broadcasting software on the Linux box to send the stream to Twitch or YouTube or whatever works.
I don't know nearly enough about cameras to know where to start. If it could be done for under $100, that would be a great start - not looking for super high quality, just like a nanny cam situation but on a smaller scale. I've felt a little lost looking online, as it seems many of these consumer surveillance cameras all have their own specific apps you have to view the feed through, with limits, etc, and I just want to be able to access the feed directly so that I can forward it on to the internet.

You can use old(ish) Android phone to have all-in-one solution or you can use go-pro camera with laptop.

I'm worried about getting a phone mounted and keeping it live for long periods of time (I know my phone turns into an oven just about when using it while it's plugged in), plus the quality in the dark is a concern there too. I actually think our videography department here has a GoPro they never use... What would be the sort of setup involved to get that working over the internet?


text:
How to copy timecode value from a video to clipboard on a mac
Is there any app that can copy timecode values to clipboard?
I'm playing a video.  I want to stop the video, press a keyboard shortcut, then go to a google doc and paste the timecode value (not a video frame).
I'm using a Mac.  Tried googling for solutions in Quicktime Player, Adobe Premiere, Final Cut, but can't find anything.  Any ideas?

This can be done in Apple's Motion (but not FCPX for some reason). To do so, create a new project and import your footage. You'll want the project's frame rate and starting timecode to match the footage's. Next, set the timeline to display timecode by clicking on the downward facing arrow next to the timecode:

Select the Timecode option:

Then double-click to select the timecode:

Now you can copy/paste it or type in a new value to jump there.

Hi.  My question is whether there's a single keyboard shortcut in any of these apps which can grab the timecode value without having to go through the extra steps you've outlined. Thanks.

I'm not aware of any. To do this in Motion, once you do the initial setup, it's just a double-click and Cmd-C to copy. Not too onerous, but I don't know of any that are less than that.

I know this is an old question, but it came up in a google search I was doing.  So, in case this helps, I've been using a program called TCode4 that does exactly what you're asking for:  http://timecodesoftware.com/tcode
A couple caveats: I think the video needs to have a separate timecode track, not just burned-in timecode.  Also, when I open it recently, I get a message saying that it needs to be updated.  I'm assuming it's a 32-bit app that needs to be updated to 64-bit for Catalina or something like that, and I'm not sure that it will be.  That is, I'm not sure the program's still in active development.


text:
Extracting segment from .mpg file using ffmpeg; why does result have video but no audio?
I'm trying to extract a segment from an .mpg file using ffmpeg, using this command.
ffmpeg -ss 0:00:06 -t 0:01:39 -i capture(0).mpg -vcodec copy -acodec copy test.mpg

The input file has both video and audio, but the resulting file has only video--no audio. I verified this in VLC Player and ffplay.exe.  What am I missing?
This is the output of the above ffmpeg command:
Guessed Channel Layout for Input Stream #0.1 : stereo
Input #0, mpeg, from 'capture(0).mpg':
  Duration: 01:06:14.08, start: 0.224400, bitrate: 9680 kb/s
    Stream #0:0[0x1e0]: Video: mpeg2video (Main), yuv420p(tv, top first), 720x480 [SAR 8:9 DAR 4:3], 29.97 fps, 29.97 tbr, 90k tbn, 59.94 tbc
    Stream #0:1[0xa0]: Audio: pcm_dvd, 48000 Hz, stereo, s16, 1536 kb/s
File 'test.mpg' already exists. Overwrite ? [y/N] y
[mpeg @ 0000028434ef5c40] VBV buffer size not set, using default size of 130KB
If you want the mpeg file to be compliant to some specification
Like DVD, VCD or others, make sure you set the correct buffer size
Output #0, mpeg, to 'test.mpg':
  Metadata:
    encoder         : Lavf57.71.100
    Stream #0:0: Video: mpeg2video (Main), yuv420p(tv, top first), 720x480 [SAR 8:9 DAR 4:3], q=2-31, 29.97 fps, 29.97 tbr, 90k tbn, 29.97 tbc
    Stream #0:1: Audio: pcm_dvd, 48000 Hz, stereo, s16, 1536 kb/s
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
  Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
frame= 2977 fps=915 q=-1.0 Lsize=  119500kB time=00:01:39.22 bitrate=9866.2kbits/s speed=30.5x
video:100235kB audio:18659kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.510136%

ffplay console output (on the resulting output file):
[mp2 @ 00000181ee26fee0] Header missingvq=    0KB sq=    0B f=0/0
    Last message repeated 8 times
...many similar results omitted here
[mp2 @ 00000181ee26fee0] Header missingvq=    0KB sq=    0B f=0/0
    Last message repeated 9 times
[mpeg @ 00000181ee25b400] decoding for stream 1 failed
[mpeg @ 00000181ee25b400] Could not find codec parameters for stream 1 (Audio: mp2, 0 channels, s16p): unspecified frame size
Consider increasing the value for the 'analyzeduration' and 'probesize' options
Input #0, mpeg, from 'test.mpg':
  Duration: 00:01:39.47, start: 0.500000, bitrate: 9841 kb/s
    Stream #0:0[0x1e0]: Video: mpeg2video (Main), yuv420p(tv, top first), 720x480 [SAR 8:9 DAR 4:3], 29.97 fps, 29.97 tbr, 90k tbn, 59.94 tbc
    Stream #0:1[0x1c0]: Audio: mp2, 0 channels, s16p
   3.98 M-V: -0.032 fd=   4 aq=    0KB vq=  988KB sq=    0B f=0/0

I am able to get both video and audio if I change the audio codec and container format, using the following options, e.g.:
 video codec: copy     audio codec: aac         output file .mkv
 video codec: copy     audio codec: aac         output file .mp4
 video codec: copy     audio codec: libopus     output file .mkv

However, I prefer to just copy the streams for performance reasons.

Until very recently (2018-02-17), ffmpeg wasn't able to correctly remux pcm_dvd streams in MPEG-PS. You'll have to upgrade to a recent version. Get a git snapshot binary from FFmpeg (under More Downloading Options)
You can also just re-encode using -acodec pcm_s16be


text:
GoPro Recording Without A Phone Connection
I was just wondering whether one is able to use, operate, and record on a GoPro without connecting to a mobile device or GoPro's mobile applications. Some insight would be greatly appreciated.

Yes, it is entirely possible to use, operate and record on a GoPro.
You won't be able to view any of the photos/video you have taken without either connecting to a mobile device OR viewing the footage you have taken on the MicroSD with another device such as a PC or Mac.
The GoPro cameras have a fairly wide angle lens which is helpful considering the cameras don't have a display built-in. GoPro sell removable LCD touch screens that can help you to frame your shot.


text:
How to create an effect of eyes opening and closing in first person perspective when awaking from syncope?
How to create an effect of eyes opening and closing in first person perspective when awaking from syncope? AE, PR or Final Cut Pro any software is OK. How to create this effect? Or are there any templates or tutorials relating to this?

When you say syncope, what do you expect to be different than awaking from sleep?

Syncope is also called "blacking out". So it kinda follows that you might fade in from black…? This effect is in every NLE usually as the default transition.
If you wanna get artsy, maybe you could add say, a blur that gets progressively less blurry as the transition proceeds.
But really, it totally depends on what you want it to look like. Is there a director for this video? Making creative decisions about stuff like this is their job.


text:
ffmpeg - cubic-bezier for drawtext movement
as you know, we can add "time" variable to "x" parameter on Drawtext, to move the text; usually we have linear transformation ( t+100 ), buy I'd like to reproduce a kind of "Cubic Bezier" effect to my text, while it cames into the scene.
This is a final effect:
http://cubic-bezier.com/#.6,.01,.4,.99
Has someone ever tried to reproduce this kind of effect?!!


text:
Premiere: Make music sound like it's coming from huge speakers?
The problem with my clip:
It was recorded on a fashion show and my recording for some reason stopped, but I quickly restarted it, so approximately 2 seconds are missing. On the visuals, not much was happening at that moment, so a cut is not that noticable luckily.
BUT: music was playing in the background, so it doesn't matter how I cut, in the audio, you obviously hear the cut. My solution for this problem is to download the original song, bring it to Premiere, put it in place between/under the 2 pieces of clip.
QUESTION:
I need this audio to sound like it was recorded "on-set", like the song was played on a huge speaker in a 10m x 20m hall. I tried the audio effect highpass, but with that, it sounds like it was played on a phone, since it eliminates lower frequencies. I tried a few other filters, but since I'm not really into that topic, I couldn't make it convincing.
Thanks for the help.

We really need a half minute each side of the problem; use YouTube  UnListed, or DropBox, etc. --- You need the audio effect "lowpass" for big speakers, highpass will be tinny (as you discovered) --- To fix be prepared to cut a bit more than you wanted (thus the need for a 1/2 minute each side, at least). Cut it so the music plays, it cuts, and then the next scene jumps (along with the music) to the next Bar (a music term); the visual jump will be obvious but the music will be smoother and less jarring. Need an actual exact answer?, let's see the clip.

You might be able to use the existing audio and the Audio Remix feature in Audition to fill in the gap. This should work well with a steady, repetitive beat. It might not be suitable if there is a lot of background noise.

I've had good luck by sampling a bit of the video's audio from another point, and splicing that in.  The tone will be dead-on consistent.  You just have to find a point in the song where it basically repeats itself (or close enough).  If you lost verse lyrics, this gets much more problematic fast.  But if you lost chorus, or instrumental bridge, intro, or outro, you could make a patch that manages to not distract.  It the song was well-known, a forced splice will be more evident, but might not seem your doing (you know?).  At the other extreme, if the song is house music, you're golden: no one will know what it was supposed to do for those two seconds.

Of course, you need to flange the volume cross-overs between original and splice, cleanly, by ear, or it will still scream out its presence.  I find doing that with manual adjustment of volume levels (with the audio files/clips overlapping on separate audio tracks) works better than using the automated tools for volume crossover at a splice edge.

You should try adding a reverb effect on the original audio. Something like a big hall or church setting, tweaking with the parameters (a small change can have huge effect !) and blending level might sound "realistic". It will probably work better than just high or low pass.
Although you might also try to apply some EQ on the reverb, it works usually well to shape the reverb sound.
There are a lot of free VSTs that simulate reverb, you might have to try several to find one you like.
I use a lot Variety Of Sounds epicVerb for music production, not sure how it would work as an prominent effect.

Thank you all for the answers!
Honestly, I didn't really want to download new programs and stuff so I worked in Premiere and finally I managed to make it sound decent enough.
I worked with a couple of audio effects:
1. I used a Convolution Reverb with the Classroom preset and a little bit of tweaking.
2. Then I applied a Fill left with right, since the CV made the singer's voice sound too much to the left due to the mixing.
3. EQ: I turned a little bit down the higher frequencies.
4. I added a Bass boost of 3 dB.
This solution probably doesn't work that well in other scenarios, but it made convincing-enough results for me this time, but I'll try out your advices in the future.
Thanks!
AJ


text:
How can I edit out the flicker from a projector from existing video footage?
I recently filmed some content of a thin line of a projected image. The video footage is flickering a little and I am wondering if there's any solution to fix the footage once it's been filmed. I have tried to speed up and slow down the footage and it doesn't seem to change it. Is there any way of editing it out on imovie? Thanks!

Possible duplicate of How can flicker from a slide projector be removed from existing video footage?

tomh's advice to double stack the video layer, reduce opacity by 50% and advance a frame is a great starting point and certainly works well on fluorescent light flicker.
I've just had the same problem with a single chip DLP projector image in shot with the banding looping over about 5 frames. Working in Premiere Pro, I layered the video 3 times, cropped each layer to the projection screen area, reduced each layer to 25% opacity and advanced each layer 1 frame on from the last. I also reduced the brightness on the base layer by 100% (referring to Lumetri Scopes and using my eye to avoid blowing out the slide image). It's a very satisfactory result.
Caveat: If anything crosses the projected image is will look like it has a strobe effect and any animations, video or transitions will have this also, however for a set of static slides you should be fine.
I got a bit carried away and made an example video...
Hope this helps you or anyone else using a search engine to love their quirky issues like i did to find the original post.

It would help a lot if you provided a sample showing the problem.
The flicker usually comes from a mismatch between the camera recording the footage and the projector projecting it.  If it's a film projector it might be running at 24fps.  Most video recorders run at 25, 29.97 or 30fps.  But even if you have a matched frame rate you will still get flicker because the camera and projector's clocks are not synchronised - so one will be in the process of closing a frame when the other is still recording a frame, hence the flicker.
You can sometimes reduce the visibility of the flicker by duplicating the video track, moving it forward by one frame, setting the upper track to be semi-transparent, and see if this helps... Example tutorial here (but not for iMovie);
https://nofilmschool.com/2018/08/super-simple-editing-hack-will-fix-your-flicker-quick
Otherwise you might need to use a more advanced programme like Premiere or After Effects with a de-flicker plugin of some kind - a few below (most are designed for removing flicker in time lapse videos though, not what you have...).  Try a demo before you commit to buying these.
https://revisionfx.com/products/deflicker/
http://granitebaysoftware.com/Products/ProductGBD.aspx

I am sure you could do it in another program, like PowerDirector but iMovie is a stretch.  If it is random black frame, you may be able to cut those black frames out of the movie so it looks like a completely smooth video.
You would do this by doing frame by frame and when there is a black frame, click the Split button and then find the end of the black, split it again and then delete the part that you  separated

Can you recommend a program where it can be done? Can you be more specific about the second part of your answer? What does "random because of picture" mean? How exactly would you "split them and delete them"?

Edited to make it clearer ^^^^


text:
ffmpeg - line_h option not found in latest version of ffmpeg
I'm trying to use the option line_h of drawtext filter, with last build of ffmpeg
ffmpeg version N-45325-gb173e0353-static https://johnvansickle.com/ffmpeg/  Copyright (c) 2000-2018 the FFmpeg developers
  built with gcc 6.3.0 (Debian 6.3.0-18+deb9u1) 20170516
configuration: --enable-gpl --enable-version3 --enable-static --disable-debug --disable-ffplay --disable-indev=sndio --disable-outdev=sndio --cc=gcc-6 --enable-fontconfig --enable-frei0r --enable-gnutls --enable-gray --enable-libfribidi --enable-libass --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librubberband --enable-libsoxr --enable-libspeex --enable-libvorbis --enable-libopus --enable-libtheora --enable-libvidstab --enable-libvo-amrwbenc --enable-libvpx     --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxvid --enable-libzimg
  libavutil      56.  9.100 / 56.  9.100
  libavcodec     58. 14.100 / 58. 14.100
  libavformat    58. 10.100 / 58. 10.100
  libavdevice    58.  2.100 / 58.  2.100
  libavfilter     7. 13.100 /  7. 13.100
  libswscale      5.  0.102 /  5.  0.102
  libswresample   3.  0.101 /  3.  0.101
  libpostproc    55.  0.100 / 55.  0.100
Input #0, image2, from 'source/img001.jpg':
  Duration: 00:00:00.04, start: 0.000000, bitrate: 12723 kb/s
    Stream #0:0: Video: mjpeg, yuvj420p(pc, bt470bg/unknown/unknown), 1024x768 [SAR 1:1 DAR 4:3], 25 fps, 25 tbr, 25 tbn, 25 tbc
[Parsed_drawtext_4 @ 0x45699c0] Option 'line_h' not found
[AVFilterGraph @ 0x4581440] Error initializing filter 'drawtext' with args 'fontfile=Roboto-Regular.ttf:enable=between(t,0,6):line_h=20:text=

I'm talking about this filter option:
line_h, lh
the height of each text line

Is this a deprecated feature? how is possible that this option is not found in last version of ffmpeg?
Thanks

line_h is not an option. It is a variable that can be used in expressions and its value is the height of the tallest character in the text.


text:
How scale rectangle in one direction without roundness scale
Property "Size" scale rectangle in two directions, like a mirror. And "Scale" distort roundness.
How scale rectangle in one direction without roundness scale without expressions?

Assuming this is a shape layer created with the rectangle tool, you can solve this by going to Shape Layer 1 -> Contents -> Rectangle 1 -> Rectangle Path 1 -> Size, and unchecking the icon that looks like two chain links, and then changing either of the two numeric values independently to change either the width or height of the rectangle, without changing or distorting the roundness.

This change Height or Width in two directions: top and bottom, left and right. How change only bottom direction?

@IvanSokolov set the anchor point y valueto 0. You'll have to adjust the position to make up for this.

Since copying from a youtube video is annoying, here's the expression put in content > transform > anchor point:
box_width = content("Rectangle 1").content("Rectangle Path 1").size[0];
box_height = content("Rectangle 1").content("Rectangle Path 1").size[1];

[box_width/2, box_height/-2]

Yeah, it's really annoying that it does that, the shape layer defaults to an anchor point that is centered in the box. The workaround that I use is to use an expression to link the anchor point the box dimensions like this:

Then I think it will work the way you want it to.
You can use the expression by following the steps below and in this screen capture video.

Option click to enable expressions for the anchor point of the shape layer.
Pickwhip to the box size to get the expression started.
Make some adjustments so the 2 anchor point values are negative one half of the size values.

If anyone knows an easier way to accomplish this, I'd love to learn it.

Can you share the expression and how to use it?

Sure, I option click to enable expressions for the anchor point of the shape layer, then pickwhip to the box size to get the expression started, then make some adjustments so the 2 anchor point values are negative one half of the size values. Maybe it would be easier to see how I did it, I made a screen capture video here: https://youtu.be/ivcrBtQifeY

Very helpful! I added that to the answer.


text:
Frame-by-frame h.265 transcoding
I'm capturing 240 FPS footage from the Go Pro Hero 6 Black in a lab setting, and I need to be able to review the footage frame by frame.
Right now, I'm attempting to transcode the h.265 video output (from the go pro) using "HandBrake" so that I can open it in a free video editor (DaVinci Resolve). I have tried toying around with the handbrake settings, specifically changing "Framerate" (in the video tab) to "same as source", but have had no success.
I'm not tied to any software or method, I just need to view the 240 FPS footage frame-by-frame somehow. My boss would prefer a way of doing this without paying for any software licenses, but obviously employee time has a cost too so if a method requiring paid software is much faster, then so be it.
Any help or advice is greatly appreciated!

What is currently happening when you try this?

AFAIK, Handbrake won't allow you to conform the framerate i.e. keep all frames but retime them.  If you're ok with a commandline tool, ffmpeg can do it.

Currently the transcoder outputs ~24 fps video (i.e. when I import the clip to DaVinci resolve and step through frame by frame, I get around 24 fps). I'm using 240 FPS footage of a millisecond-accurate stopwatch to verify this result.
I will check out ffmpeg, thank you for the tip!


text:
ffmpeg - Zoompan IN and Out alternately
I'd like to apply a Zoompan effect but instead of zoom in or zoom out, I'd like to mix both of them: the zoom will start with zoom in, and, after some period of time, the zoom continue with zoom out, and so on, alternatively.
While I'm thinking how to archieve this, has someone some tips?
Thanks !

You need to use state e.g.
ffmpeg -i src.png
 -vf zoompan=d=300:z='if(gte(zoom,2)+eq(ld(1),1)*gt(zoom,1),zoom-0.04*st(1,1),zoom+0.04+0*st(1,0))'
o.mp4

This expression zooms from zoom=1 to zoom=2 in steps of 0.04. Remember, zoom is initialized to 1. The above will create 6 loops.
In st(store) and ld(load) functions, the first argument is variable id (0 to 9), and the second is the value.

good, it works, but I don't understand very well  what does it do! What if I'd like to start with zoom out and then zoom in? Thanks!

Actually, I use  pzoom for z evaluazion min(pzoom+0.0015,1.5), and before zoompan I scale the image with scale=iw*10:ih*10. I'm trying to apply your formula, but it does not work. How should I change to use pzoom?

Sorry, it works well; I have updated my ffmpeg version with 3.4.2. Thanks!!!

@Gyan How can this effect be done in videos, with it zooming into the center?

d=1 and use pzoom in place of zoom

@pigeonburger check this you may adapt it for a video : https://superuser.com/questions/1087685/ffmpeg-zoompan-image-to-center-position

Based on Gyan's answer, here are more details.
The following creates a video from an image and an mp3 with an infinite zoom-in-out on the image:
ffmpeg -loop 1 -i img.png  -i adio.mp3 -vf "[0:v]scale=7680x4320,zoompan=z='if(gte(zoom,1.5)+eq(ld(1),1)*gt(zoom,1),zoom-0.00005*st(1,1),zoom+0.00005+st(1,0))':d=20000" -c:a copy -c:v libx264 -shortest out3.mp4

[0:v]scale=7680x4320 upscales 4 times the original 1920x1080 image for a smooth transition.
d=20000 specifies the duration of the zoom-in-out. In this case, I perform a zoom from 1 to 1.5 with increments or decrements of 0.00005. That's (1.5-1) / 0.00005 steps for the zoom, which means I need two times this for the zoom + dezoom, which is 10'000*2 = 20'000.
if(gte(zoom,1.5)+eq(ld(1),1)*gt(zoom,1),zoom-0.00005*st(1,1),zoom+0.00005+st(1,0)) can be translated to the following pseudo-code:
// '||' corresponds to a `+` and '&&' to a '*'
if zoom >= 1.5 || (isDezooming && zoom > 1) {
  zoom-0.00005
  isDezooming = true // corresponds to '*st(1,1)'
} else {
  zoom+0.00005
  isDezooming = false // corresponds to '+st(1,0)'
}

where isDezooming corresponds to the variable 1 handled with the ld(1) and st(1,0) instructions. Here is the full list of instruction.


text:
Streamer Glow Effect: Star Trek New Generation - S.7 E.11
I was watching this episode and was amazed by the effect that they did to the streamers.
How would they pull this off?
I couldn't capture a picture of this but ill try to explain it.
The streamers glow but they are also behind, in front and on the characters. There is no glowing on anything else. The streamers are real objects that have been glowed.
Thanks.

It might help you get answers if you can illustrate this effect with an image, screengrab, anything.

Apologizes for the delay, I can probably explain this as an glow effect on the objects that they threw. But what threw me off was the fact that the objects flew behind the actors and the effect didn't show on anything else.
I can probably justify this now with the fact that the colours on the streamers where high vis or something reflective to light.


text:
Import secondary audio track along with video mpg into Adobe Premiere Pro
I've been trying for hours to import an mpg along with its secondary audio track into Adobe Premiere Pro.  Only the primary track is imported.
I know this mpg has two tracks because I can play the file in the VLC player with the setting Audio > Audio Track > Track 2 [Spanish] and the secondary audio track plays.

I have tried setting audio preferences insuring all default audio
tracks are using "Use File".
I have tried setting the track tab in a new sequence to
"multichannel" with "number of channels" = 2.
I have also tried modifying the imported mp3's audio channels.

I have also searched online and in YouTube but still no answers.
Please advise.  Thanks!

According to this post, it should work with Adobe Premiere CC.
And after importing it should look like this:

If you are using a really old version of Adobe Premiere, you could download the latest trial version to check it.


text:
In Adobe Priemiere Pro CC, export media window does not appear
In Adobe Priemiere Pro CC 2018, when I use the File > Export > Media menu item, the export media window does not appear!
I've confirmed that it's not merely hidden behind other windows or on another monitor.
I have up-to-date software (currently version 12.0.0 and I'm running Adobe Media Encoder CC 2018.

Called Adobe support, and they quickly solved the problem.
The export media window apparently only appears if the currently selected/highlighted workspace panel is either the video timeline panel or the playback panel. If any other panels are currently selected instead, the window will fail to appear.


text:
Best lossless codec
What is the best codec at the moment without losses? HEVC, or is it faster / more compact? In HEVC there is a lossless mode. On the Internet did not find the actual information for this year.

What are the criteria that define best to you? The best professional mezzanine codec is different from the best scientist research codec is different from  codec.

It entirely depends on your definition of best. Different codecs do different jobs:

Do you require greater bit depth than 8-bit? Some codecs encode 10,
12 or 16 bits per channel, giving much higher colour fidelity, and
lower quantisation errors.
Do you need an alpha channel? Some codecs support an alpha channel to
encode transparency information, important for intermediates used in
the post production chain.
How efficient do you need the codec to be, i.e. how much file
compression does it offer? Lossless codecs are usually fairly
storage-hungry.
How fast is it to encode/decode? This is usually roughly inversely proportional to the efficiency. However speed also depends on the speed of the storage, so a codec that requires less processing per frame might have a bottleneck at the point where the frame is retrieved from disk especially for high resolution video.
Do you need to edit with it? Codecs that use GOP can be slower to use
in editing or post production.
If you're giving the footage to someone is it likely that they'll be
able to use it on another system without too many hurdles? Is it free
to use? HEVC is free for a limited number of views, but if you're
using it to distribute content to a mass audience you'll be up for
royalties.
Other considerations like is it an open source codec with publicly
available description of the bitstream. Of critical importance for
long term archival, but generally unimportant for any other use.


text:
Synchronize Video / Audio with different numbers of audio channels
I have a main video recording and audio recordings from 2 phone-based lav mic's. One subject's lav recording has 2 audio channels and the other has 1. (The video also has 1 audio channel)
I can synchronize the 1-CH recording to my video, but trying this with the 2-CH recording says could not synchronize one or more clips in the current selection because a match could not be found.
How can I sync the 2-CH audio file to my video? I'd assume that there should be a feature to automatically synchronize based on the lowest common number of Channels. Thank you!


text:
Why is Adobe Premiere not letting me apply a filter to this sound clip?
I have a sequence with various clips, one came from a multi-cam and the other one straight from a video. I had no problem applying the filter to the multicam one:

But when I try to apply it to the other one, it won't let me:

Any ideas why?

Check to see if the filter is restricted to specific audio file / stream / track types.
For instance, I believe you’ll get the same issue if you tried to drop filters that apply only to Stereo Tracks to a Mono File Track, such as Swap Channels, Fill Left, Fill Right, etc. Because its impossible to swap left and right channels when youre on a mono track.
You dont specify what filter, but thats my guess.
Same goes with Video Filters... there are some filters you cant drop onto video tracks with Alpha, or vice versa.


text:
What is the word for left thirds?
There is lower thirds in which a title and sometimes, a subtitle appears. They usually appears at bottom left of the screen. However, I am looking for examples in which a speaker (or focus of object) is on the right side of the screen and the text and graphics animate in on the left side of the screen.
I couldn't find any good examples of text animation that animate in on the left side. It should be something like this video.
This is the video that I am using, Medical colleagues chatting. There's plenty of space at the left side in which I was planning to add the logo and three bullet points.
I wanted to find some good simple text animations for left side in adobe after effects or some free templates or something like that.
So what keywords should I use to search for left side thirds?

I don't have a word for it,  I always called it left third or left panel,  and had my title artist build what we needed


text:
How can I extract clips from a streaming video feed in near real-time?
A client wants me to write some software, perhaps ffmpeg wrapped in scripting, which will monitor a streaming video feed, and copy clips from it in near real-time, delivering them as self-contained video files. It is not acceptable for me to wait for the feed to finish, and the video to be completely stored as a local file, before I copy the clips. On the other hand, I can take say tens of seconds after the end time of the clip before delivering it. Can I do this without building a video processing suite from scratch? Do I need to require that the streaming video feed be a certain format?
So say the video feed is of a 1-hour live event. At some point, maybe 5 minutes in, my software may get the command, "clip from 4 minutes 30 seconds to 6 minutes 0 seconds, save as file X.mpg". I have to tap into the video feed, copy 90 seconds of video, and store it as file X.mpg, by about 7 minutes in.  The actual times are more flexible, I just want to emphasise that I must be able to tap into the streaming feed in progress, I can't wait for a static video file.
I don't even know if streaming video formats permit this kind of operation. If a receiver writes the feed to disc, will the beginning of the file be legal syntax which a normal tool like ffmpeg can parse?
I don't know details of encoding formats, but I understand that they store key frames every so often, and intermediate video frames are stored as differences from the key frame and/or preceding frames. Is it important to know when the key frames are added?  Can normal tools parse video past the most recent key frame to the frame just being written, or would the data in the stored file be still be in some temporary state, and thus not yet parseable?
Or, is copying video clips from streaming video a difficult task which requires more sophisticated software than ffmpeg or the like, wrapped with scripts?
Advice on specific formats, and tool chains which make this possible are welcome.

This is fairly straightforward if you save to a streaming format like Flash Video (FLV) or MPEG-Transport Stream (MPEG-TS).
Let's say this is your full feed capture command
ffmpeg -i source {-transcoding options} localfile.flv

You can then run
ffmpeg -ss 6:12 -i localfile.flv -t 1:05 -c copy extract.mp4

Ideally, the stream should be past 7:17 or close to it when you run the latter command. Note that since the 2nd command doesn't transcode, inpoint seek isn't precise. The extract will start from the nearest keyframe earlier to the specified inpoint.


text:
Getting audio components from two audio streams to remove noise
As a computer scientist, I know that it is possible to decompose two signal streams (such as audio) using the SVD (Singular Value Decomposition), to get the most natural bases for the signals.
This is very useful because you could, in theory, record with two microphones to remove background noise. For example, one microphone near the speaker, and another far from the speaker. The one that is near the speaker will have a stronger speech and weaker noise, on the other hand, the far microphone will record stronger noise and weaker speech.
The problem is that I don't know of tools to accomplish this. Also I don't have a clue of what to look for, since I am not a professional in video editing. All I can find is tools to remove noise based on one audio only.

So, you'd be inverting the phase of the noise signal, adjusting its amplification to match the level of the noise in the other clip, and then summing the two to obtain speech minus noise. You might find that adding EQ. to the noise signal as well as amplification might also help.
Any audio app that can mix two signals could do this, if you want a good free one Audacity is the most widely used.
This technique is used in a electomechanical sense in a lip-ribbon microphone, commonly used in sports commentary.


text:
ffmpeg tile command: ordering frames top to bottom rather than left to right
By default, the tile command builds the output one row at a time, from left to right.
I would like instead for my output to be built in columns, top to bottom.
That is, for a 4x4 tiling, the tile command by default arranges the frames like so:
    1  2  3  4
    5  6  7  8
    8  10 11 12
    13 14 15 16

Whereas I would like for them to be arranged like so:
    1  5  9  13
    2  6  10 14
    3  7  11 15
    4  8  12 16

What is the easiest way to make this happen?

You can't change the behaviour of the tile filter, but you can adjust your inputs before and after to get the desired result.
ffmpeg -i input -vf hflip,transpose=cclock,tile=4x4,transpose=clock,hflip out.png

Note that the layout supplied to tile is transposed, so if you want the final result to be 6x4, tile should be given 4x6.


text:
Why when I overlay a logo on top of the video, the white color part of the logo is transparent?
I overlay using the following command:
ffmpeg -i video.mp4 -i logo.png -filter_complex "[1]geq=r='r(X,Y)':a=0.1[a];[0][a] overlay=x='if(gte(t,2), -w+(t-2)*20, NAN)':y=0" out.mp4

I tried adjusting the opacity using
fmpeg -i video.mp4 -i logo.png -filter_complex "[1]format=rgba,geq=r='r(X,Y)':a='1*alpha(X,Y)'[a];[0][a] overlay=x='if(gte(t,2), -w+(t-2)*20, NAN)':y=0" out.mp4

but it is still transparent at the white color part.
It seems like the white color part has a transparency of 0, causing the second command to not work.
Is there any reason why this is happening? The logo I tried is

How can I preserve the white color?

There is no white color. That's the background color of the page showing through. Your input PNG is palettized 8-bit image where black color indicates transparency.
Apply the following filter to the image to convert black pixels to white and set a uniform transparency.
geq=r='if(p(X,Y),p(X,Y),255)':g='if(p(X,Y),p(X,Y),255)':b='if(p(X,Y),p(X,Y),255)':a=0.1

I dont quite understand what do you mean by black color. I dont see any black color. Also, can you kindly explain what is p(X,Y)? The documentation says pixel at the current plane which is kind of vague.

The actual color stored in the PNG in the area of the 'f' is black, which the viewer interprets as transparency. My geq expr checks if a pixel is non-black. If so, it keeps it, else changes it to white.


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FFMPEG Filter_Complex_Script crop by time
I am trying to use FFMPEG's filter_complex_script option to crop a video in different places depending on the time. I have a file that shows the bounding box of where an object should be and have written a text file called "myscript.txt" that has commands as follows:
crop=x=125:y=190:w=105:h=98
crop=x=124:y=193:w=106:h=99
crop=x=124:y=194:w=106:h=99

My command line call for ffmpeg is
ffmpeg -y -i input.mp4 -filter_complex_script "myscript.txt" -c:v libx264 output.mp4

This will run fine and produce an output, but the crop window only uses the first line of the file and does not change over time. Currently I have cropping details at the frame level but I can find a way to make this work by second if there is a solution out there.
I am running FFMPEG version 3.4.1 on windows 10.
Thank you!


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How to disable putting black frames between concatenated media with ffmpeg?
I am using the concat demuxer in ffmpeg. I use the following command:
ffmpeg -f concat -i concat.txt -c copy out.mkv

and it works, except that it adds short gaps of black frames in between the concatenated files (there are three of them). How do I make it stop? If it helps, the audio is cut at those points, too.
I know that a parameter for this exists, but I can't find the original question anywhere.
Thanks in advance.

Share the results of ffprobe input for all three files and also the content of concat.txt

This can happen if the "streams do not have exactly the same length". You have to specify the range to include for the items in concat.txt. Try specifying the duration or outpoint or in point:
https://ffmpeg.org/ffmpeg-formats.html#concat

The duration of each file is used to adjust the timestamps of the next file: if the duration is incorrect (because it was computed using the bit-rate or because the file is truncated, for example), it can cause artifacts. The duration directive can be used to override the duration stored in each file.

From the Q - in between the concatenated files - so not within the files.

Don't use duration - it is meant to override the value the concat demuxer uses for calculation, not for trimming -use. outpoint for that.


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Consumer grade vs professional audio
Newbie issue!
I was given 12 miniDV tapes and the Canon ZR900 camera they were recorded on to transfer onto memory sticks.  I used FW400 into a Dell XPS 9100 to capture using Filmora. No problems at all. Excellent AVI's
At the same time I was also given 12 other miniDV tapes that were recorded but using a 'professional' camera of an unknown brand.  When capturing those tapes using the consumer camera I have no audio.  Actually I can hear waaay in the distance the audio with occasional 'bursts' of sound when I crank up the volume.  What Might be the first obvious issue I may be having.  Thank you.

The first thing I would do is find another machine to play them on to isolate the problem. The tapes might be recorded as DVCam rather than DV, although the tapes are the same, the data is recorded differently. Are you seeing pictures?

Can you post pictures of the physical cassettes? That would help answer @stib's question about the format difference.

Problem is that you can record DVCam on DV tapes. The tape just runs at a higher speed, so a 60minute DV tape gives you 46 minutes of DVCam

Thanks for the suggestions!  The video is excellent on playback using the Canon camcorder, I'm only lacking the audio, or to be precise, the audio is barely audible unless cranked.   I think I'll locate another consumer camcorder as first suggested.  I've hit the books on understanding the many video formats now and hopeful I'm not playing back a DVCam format unless the Canon consumer camera can playback that format. The tapes are TDK miniDV ME.  Thanks for the suggestions. You have no idea how much it helps.  Off to find another camcorder. I love a challenge!

I've been looking on eBay and see a bunch of decks that will do miniDV and or DVCam.  JVC dsr11,  JVC BR dv3000u,   JVC BR Dv600 etc.  Anything I should look out for or suggestions on getting one of these models. Maybe a Sony, don't know the difference.  Thanks.


text:
How to produce assemble effect in software product videos
I have seen in different software product videos that the UI is assembling during the video. How is such an effect produced?
Here are a couple of examples:
Lumiar:

Salesforce:

How are these sequences produced? Which tools are getting used?

These sequences are produced using Animation™. Animation™ is the technique of manipulating objects or images to create the appearance of motion. If you look closely at the sequences, maybe slowing them down so you can step through them frame by frame you'll be able to see what's going on, and then you just have to work out how to do it with whatever tools you use.
I'd say screen shots of the UI elements have been chopped up with an image editor (e.g. , CinePaint, Darktable, DigiKam, F-Spot, G'MIC, GIMP, GimPhoto, GIMPshop, GNU Paint, GrafX2, GraphicsMagick, gThumb, Hugin, ImageJ, ImageMagick, Inkscape, KolourPaint, Krita, LazPaint, LightZone, MyPaint, Panorama Tools, Pencil2D, Phatch, Pinta, Rawstudio, RawTherapee, Seashore, Shotwell, Tile Studio, Tux Paint, UFRaw, XPaint, Brush Strokes Image Editor, Chasys Draw IES, FastStone Image Viewer, Fatpaint, Fire Alpaca, Fotografix, IrfanView, MediBang Paint Pro, Moai[1], Paint.NET, PhotoScape, PixBuilder Photo Editor, Pixia, Project Dogwaffle 1.2 Free Version, XnView, Ability Photopaint, ACD Canvas X (formerly Deneba Canvas), ACDSee, Acorn Image Editor, Adobe Photoshop, Adobe Photoshop Lightroom, Adobe Photoshop Elements, Affinity Photo, ArcSoft PhotoImpression, Artipic, ArtRage, Autodesk SketchBook Pro, Bloom Image Editor, Capture One, CodedColor PhotoStudio Pro, Corel Painter, Corel Painter Essentials, Corel PaintShop Pro, Corel Photo-Paint, Erdas Imagine, GraphicConverter, Helicon Filter, Iridient Developer, LView Pro, Manga Studio, Microsoft Paint, NeoPaint, OpenCanvas, Paint Tool SAI, Photogenics, PhotoLine, Photo Mechanic, Photos (Apple app), Photo Raster, PicMaster, Pixelmator, Pixen, PMview, Portrait Professional, Project Dogwaffle, QFX, Serif PhotoPlus, TVPaint, Xara Photo & Graphic Designer, Zoner Photo Studio, Mara, Pixlr, PicMonkey, PicsArt).
Then the separate elements were then moved around in an animation / compositing app, e.g. Blender, Cinelerra, Kdenlive, Natron, OpenShot, Shotcut, Adobe After Effects, Apple Motion, Autodesk 3ds Max, Autodesk Inferno, Flame and Flint, Autodesk Maya, Autodesk Smoke, CompTime, FXhome HitFilm, Saber, Houdini, Blackmagic Fusion, Mistika, Nuke, Piranha, SilhouetteFX, Autodesk Combustion, Autodesk Softimage, Autodesk Toxik, Aviary, Peacock, Avid DS, Avid Elastic Reality, Avid Matador, Avid Media Illusion, Kodak Cineon, FXhome Lab, Range, Pinnacle Commotion, Silicon Grail's RAYZ and Chalice or Shake.

I believe it's just an animation video composed with several (SEVERAL; see below) layers of objects moving around in a scripted way. Probably they took a screenshot or a screen recording of those programs, disassembled them through an editing program, and then assembled them back again with the same editing program, scripting all the movements.
In the first case I guess such a video is exported at a ridicolously high definition, and is then re-edited after exportation, so that it can be moved around, tilted...
In the second video I think they attached it on the screens of the various devices using After Effects.
I specified "several" because I once did something like that, with a composing interface, for an interactive Youtube video, this one

I made it with Premiere. That menu at the beginning of the video, alone, and the way it assembles, required around 20 layers. They were quite simple, since they included only shapes with different opacities, colours and movements; yet it was impossible for my usual PC, a laptop with which I'm even able to export 4K movies, to process all those layers. I had to go to a friend's house and use his semi-pro PC made for this kind of jobs.
It's possible, though, that there are programs, such as the ones mentioned above, that can make such an animation easier compared to Premiere.


text:
Advice on camcorder that supports USB-C and 3.5mm external microphone?
I'm shopping for a video camera that I will use to record lectures that I give at my university. My setup is going to be a camcorder on a tripod plus a Lavalier wireless microphone, which I will attach to my shirt while I am presenting. There won't be a person controlling the camera; I'll just set up the camera at the beginning of class and leave it there to record. Also, I can't guarantee that I'll have external power for the camera.
I'm trying to choose a camcorder or action camera for this. Here are the features I am looking for:

3.5mm input jack for external mic (must have)
usb-c or micro-usb port for charging and data access (must have)*
screw hole for tripod (must have)
1h30m recording time without external power (must have)
at least 720p resolution (not too fussy)
price under $300 US
*I already have usb-c and micro-usb devices in my life. I see that a lot of camcorders still use mini-usb-B, which feels ancient now. I don't want an other type of cable to carry around.

Can anyone offer any advice on this?


text:
MKVToolNix Splitting and Joining Stutter
I've been trying to split a tv show episode into two seperate parts, but whenever I try to rejoin the split files, I get a pixelation look on the merge locations.
I've been using MKVToolNix to try and do the splitting/joining.
I made an example of the problem I am having.
https://i.imgur.com/2V35u2B.gifv
Right as the credits start you can see the screen blips grey, and then after that some of the credits become pixelated also.
Is there anyway to fix this problem and just have one smooth video?

Try using a different video encoder when you create the original file. If that's not under your control, you can file a bug agains MKVToolNix, the author is "always grateful for good bug reports": https://mkvtoolnix.download/
Alternatively, try using ffmpeg to join the two parts: https://trac.ffmpeg.org/wiki/Concatenate

It appears that the glitch isn't as bad when using ffmpeg. I will try submitting a bug report to the author of MKVToolNix.
Thank you for the suggestions.


text:
How can I fix a dark spot on my lens in post-production?
I need to fix this in post. Can I do it?

If you shoot an evenly lit white frame you could invert it, adjust the levels so that the non-affected areas of the frame were completely black, and then add the result to the original footage. It might take some tweaking of the levels to get it right.


text:
I dropped my Panasonic HC-V180 Camera, and now camera doesn't work?
So I had my Panasonic HC-V180 camera ready on a tripod extended to its maximum height, and then it lost balance and tipped over. The camera is able to show its storage videos and displays things like the date, whether there is an SD card or not, and its battery, menu, etc. fine but the screen is otherwise black when in video taping mode. Then after a while, the camera suddenly shows a blurry display of the camera along with an error saying "ERROR OCCURRED. PLEASE TURN UNIT OFF, THEN TURN ON AGAIN." It won't record anything.
What is wrong with it? Perhaps the viewfinder?  I have no idea where to go take it to fix (I live in Bay Area of CA, USA)

I had the same problem. After reading your problem I had to think if I'd dropped mine. I hadn't really, just plonked it roughly on its lens end. So, I tried something. I tried dropping on the battery end from only a few centimetres in height onto a table. Bang! Voila! It works....for now.

Okay, this is ridiculous, I know. I was having the exact problems shared here... And I did Matty's "plonk" technique from, like, half an inch and it worked.

As far as what is technically wrong with your camera; the answer is it’s busted. You dropped it.
As far as repair, go to the Panasonic Website, navigate to support, cameras, repairs. Depending on your camera model, it will give you your options on repairing it.
Some companies use vendors, some charge a fee up front just to accept it to determine what needs to be repaired, then quote a price for parts and labor.
But the answer to where to get it fixed is on the Panasonic website. Youll have to mail it to a service center. Then decide if its worth repairing.