12
votes
Timestamps are unset in a packet for stream 0. This is deprecated and will stop working in the future. Fix your code to set the timestamps properly
The usual solution for this situation: -fflags +genpts
It should eliminate the warning, but there's no guarantee your sync issues will be solved.
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8
votes
Accepted
ffmpeg: how to convert to DNxHR in Windows 10?
There's a single decoder/encoder which reads/converts to both DNxHD and DNxHR.
You have to set the correct profile switch. Available options are
dnxhd E..V....
dnxhr_444 ...
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6
votes
Accepted
Understanding containers and codecs
MPEG-4 is not a container specification. It's a suite of specifications. Parts 12 and 14 define containers (MP4). Part 2 defines a video codec, whose encoder implementations are DivX and Xvid. Part 10 ...
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5
votes
Accepted
Smallest Possible Video File in H.264 Format
A one frame H264 stream would have to consist of an intra-coded frame, so there is a size floor in effect.
This ffmpeg command produces a 1.7 kiB file
ffmpeg -f lavfi -i color=blue:s=1280x720 -...
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4
votes
Accepted
Do a sort of HEAC - High Efficiency Audio Codec exists?
I think HE-AAC fits that bill.
High-Efficiency Advanced Audio Coding (HE-AAC) is an audio coding
format for lossy data compression of digital audio defined as an
MPEG-4 Audio profile in ISO/IEC ...
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4
votes
Accepted
.mkv file not playing in HEVC/H.265 supported player
Both files that don't play feature Opus as the audio codec. As per this site, Opus is not one of the supported audio codecs.
Transcode the audio:
ffmpeg -i in.mkv -c:v copy out.mkv
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4
votes
Accepted
What does codec stand for?
One of the earliest articles in the IEEE database that uses the term, defines it as "coders and decoders."
However, newer material does not seem to be consistent. One of the Wikipedia page's sources (...
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4
votes
Accepted
Timestamps are unset in a packet for stream 0. This is deprecated and will stop working in the future. Fix your code to set the timestamps properly
this worked for me as an option to ffmpeg: -use_wallclock_as_timestamps 1
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4
votes
Accepted
Is MP4 a valid or common container for ProRes?
No, officially, ProRes is not a registered codec for the ISOBMFF family, of which MP4 is a member.
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4
votes
How to make video play with correct aspect ratio
For a H264 stream, use the h264_metadata bitstream filter
ffmpeg -i in.mp4 -c copy -bsf:v "h264_metadata=sample_aspect_ratio=4/3" out.mp4
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4
votes
Accepted
How can I find out which chroma subsampling (if any) is used in a video file?
Mediainfo is a free, open source, cross-platform solution, available in 37 languages. https://en.m.wikipedia.org/wiki/MediaInfo
When run from the command line it outputs chrome subsampling info by ...
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4
votes
How can I find out which chroma subsampling (if any) is used in a video file?
Using the ffprobe command (part of FFmpeg, also a command line tool)
ffprobe -show_entries stream=pix_fmt <VIDEO FILE>
The output will look like this:
...
[STREAM]
pix_fmt=yuv420p
[/STREAM]
[...
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3
votes
ffmpeg convert mp4 to mov with dnxhd codec
Your output has to match one of the requested profiles.
For the 5th profile listed,
[dnxhd @ 0000000002be23a0] Frame size: 1920x1080p; bitrate: 115Mbps; pixel format: yuv422p; framerate: 24000/1001
...
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3
votes
How does YouTube encode my uploads and what codec should I use to upload?
Your question is "How does YouTube encode my uploads and what codec should I use to upload?".
Digging deeper into your question I see: "Should I adjust my own encoding to "play nice" with Youtube's ...
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3
votes
How to encode Apple ProRes on Windows or Linux?
This is the command line I have used to encode ProRes 4444. If you do not include -bits_per_mb you will get low res results in Windows 10. Many posts do not mention this little aspect.
ffmpeg -y -f ...
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3
votes
Is there a video type for vector animation?
Here is some research about this topic:
Resolution Independent 2D Cartoon Video Conversion
https://www.researchgate.net/publication/305390110_Resolution_Independent_2D_Cartoon_Video_Conversion
Video ...
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3
votes
Is there something like nvenc for free codecs (VP8/9)?
There is a hardware-accelerated VP8 encoder recently released by the University of Milan. Source and standalone binary for 64-bit Linux and compute 3.5, 5.0 and 5.2 capable NVidia GPU cards available ...
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3
votes
Accepted
encoding with ffmpeg libx265 -pix_fmt gray gives unplayable vid
Plays fine here in VLC, ffplay and Potplayer. Doesn't play with mplayer. Its H265 decoder probably doesn't support gray.
Workaround is to store it as YUV420P after discarding the chroma.
ffmpeg -i ...
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3
votes
Accepted
how to use h264_omx on RaspberryPi
The first priority here is to determine the bottleneck, particularly on the encoding end first, then moving on elsewhere.
This is noted by the comment on the choppy video stream, indicating frame-...
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3
votes
Accepted
Why can't my video play from where I drag the playback bar?
video1 has a very short keyframe interval - it has a keyframe every few frames. video2 doesn't. Some players have the ability to decode upto non-KF silently and start playing from seek point. If yours ...
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3
votes
Accepted
Does increasing the framerate while not changing the content affects compression quality?
This depends on the specific encoder, and the compression standard, by itself, may not have anything to say about it.
x264, which encodes to H.264, takes frame duration, into account, in its ...
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3
votes
Accepted
Lossless color compression
Without knowing the video properties, my generic answer is
ffmpeg -i in.mp4 -vf geq=lum='p(X,Y)':cb=128:cr=128 out.mp4
This will reset the color information, but pass the luma plane intact. Add -crf ...
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3
votes
Accepted
AAC with no global headers is currently not supported
I assume you're the same poster as at ffmpeg-user who posted this.
.aac stores a raw bitstream and the demuxer has no facility to extract the stream parameters as extradata. So, you can try streaming ...
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3
votes
Accepted
Add timecode information to file
@Gyan gives the answer in comments:
MP4s and MOVs store only the TC of the first frame, as a literal frame count, along with the framerate. The consuming app converts that frame count back to a TC ...
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3
votes
Why is my video file so large when there isn't any video?
You have 37 minutes and 14 seconds of audio, so it's going to be at least as large as the original audio file (36Mb) plus one image and a few bytes for each frame saying "the image has not ...
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2
votes
Accepted
How to open MP4 container video with mp42 codec in Vegas Pro?
mp42 is the container ID, which Mediainfo wrongly calls a codec id. It refers to MPEG-4 Part 14 spec for containers.
XDCAM is actually a Sony variant of MPEG-2 video. I've worked with XDCAM natively ...
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2
votes
Accepted
Please Explain the Codecs in my Example
So codecs compress and decompress videos, right?
COmpress DECompress. Yep. Just like with text encoding, e.g. ascii or unicode, but with video you take a raster (grid of pixels) and turn that into a ...
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2
votes
Quality of time lapse from images
You are approaching the problem at hand very well, you have however not used the most quality-preserving solution available.
I recommend that you take your raw image files and import them into Adobe ...
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