Re: [FFmpeg-user] Question about video codecs : libx264 vs libx265
Hervé ANSELME (12024-03-31): > I have a question about re-encoding a source video having libx264 video codec. > > Is there any advantage(s) to re-encode with the libx265, which is supposed to > give better result than libx264 ? > > In other words, re-encoding with the x265 codec for the final video : > can it improve the final video quality, compared to the source video, > when the source video is encoded with x264 ? You will never have a better quality than the original, of course.¹ Transcoding with a different codec that makes different compression decisions will not even let you get exactly the quality of the original content, but if you throw enough computing power you can get almost it with a smaller size. What you can get, and where it makes sense to transcode, is a smaller file with lower quality where the lost of quality is much smaller than the gain in size. 1: You might think you can get it with AI, but it only seems better quality. If you do it too much, like if you are trying to catch the face of a replicant reflected on a whisky glass, what you will get is bits of series from Amazon Studios in your videos. Regards, -- Nicolas George ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] srt subtitle to dvbsub for mpegts stream
William C Bonner (12024-02-28): > I’m trying to find a way to include optional subtitles in the stream but > haven’t been able to find a way to convert text subtitles to raster image > subtitles. Not currently possible with ffmpeg, only with the libraries and low-level programming. Regards, -- Nicolas George ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Trouble with ffmpeg ... -f tee and specific encodings per output
Jason Bailey via ffmpeg-user (12024-02-22): > The tricky part is that the the mpegts output has very specific > requirements -- it needs to be MPEG2TS with AC3 audio. The HLS output, > however, should use HLS appropriate defaults -- h264 video, aac audio. Then the tee muxer is not suited to your needs. Regards, -- Nicolas George ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] FFmpeg interrupted (SIGSTOP signal) but pipewire shows its node is still running
gnusuario--- via ffmpeg-user (12024-02-05): > I want to know if it is possible to stop recording sound while the > process is paused (stopped in signal terms). FFmpeg cannot do ANYTHING after receiving a SIGSTOP. So you would need either sending TSTP and see if it behaves better, or take it to the authors of pipewire. Regards, -- Nicolas George ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] The Guild
David Niklas (12024-02-04): > Mark was good enough to privately email me Sorry for you. > And here I was looking forwards to the day when I could support FLOSS > devs after getting a job... sadness. > How do you know the money only comes from companies? He does not. But unfortunately it happens to be true right now for FFmpeg. In the recent years, the part of paid-for contributors has increased in the project and eventually the guys who caused the libav fork have managed to leverage this into a majority in the voting assembly and the committees, and are now behaving as if they own the project. So the recent change, where you seen fewer and fewer original features that cannot be found in any other project and serve a few users, will continue. They have broken hard-burning subtitles from the same stream, they have broken and are about to remove the SDL and OpenGL output devices. Because they are not interested in these fringe features that serve only a few users but are absolutely necessary for them. They are interested in basic maintenance, wrappers for hardware (proprietary) decoders. So expect to have only that in FFmpeg in the future. RIP FFmpeg. You were a good project to have fun hacking on. Regards, -- Nicolas George ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] FFMPEG filter_complex overlays work well on windows but generates error on Linux and OSX
Suraj Kadam (12023-12-22):
>for (let i = 0; i < pngPaths.length; i++) {
Hi. Nobody will try to understand your script in order to help you. You
need to simplify your command-line as much as possible while still
exposing the issue, and post it as is on the list along with the
complete console output.
Regards,
--
Nicolas George
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Re: [FFmpeg-user] kmsgrab and audio problem
KoreanFanOfficial (12023-12-10): > Show me your code where kmsrab working with alsa/pulse without any issue on > debian/arch system Cuz you cant, cuz this problem exist many years and > dont fixed. Do you even try to install debian/arch??? Hi. Did you forget that you got FFmepg gratis and without any warranty? You are owed nothing here, you are asking for help, so please keep it civil. And do not top post. -- Nicolas George ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Which file formats can hold image subtitles (dvdsub) without other streams
bbb (12023-12-04): > When I try to use mkv it insists on having a > video stream (... figures). Hi. I do not observe that. Please show your command line. Regards, -- Nicolas George ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] framecrc
Mark Filipak (12023-11-13): > If input PTSs & DTSs shouldn't be changed, then what use is > '-bsf:v setts=pts=:dts='? They are for people who know what they are doing. -- Nicolas George ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Seeking Efficient Video Redaction Using FFMPEG with Limited Memory Usage
Paul B Mahol (12023-11-07): > Do you have actual proof for such claims? Libavfilter is at least linear in the number of filters for each single step of the filtering. That means a filter graph with 2000 filters will take at least 200 times as much power than a graph with 10 filters. Really a lot more, because larger graphs tend to be deeper too. This is not unavoidable, this part would be rather easy to optimize. -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Requesting colormatrix advice
Michael Koch (12023-11-07): > That's a good summary of the current state. I did also try to understand > this stuff some time ago, without success. Except for this: > > Interactions between all of this are not documented anywhere. This is completely untrue, and Phil has been familiar with FFmpeg for enough time that we can consider it intentional: it is a lie. Video manipulation is a difficult topic, there are lots of ways of doing similar things that will yield subtly different results. The ability to chose the right one comes with experience and effort. Unfortunately, both Phil and Mark have repeatedly shown they had no intention of making any effort themselves, their policy is to expect somebody to do the job for them gratis and insult the project when that does not happen. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] missing meta data in ffprobe output from mp4 format
Greg Oliver (12023-10-20): > I have never used ffprobe before, but I have seen countless messages > on this left with regards to it not being closely maintained and > recommendations to use other software to query media information. It is the other way around. Regards, -- Nicolas George ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] No compiled with -fPIC for libavcodec/aarch64/vp9mc_16bpp_neon.S
Peng Gao (12023-09-12): > The link error means this error is reported when doing the link stage on > compiling OpenCV. > The error shows it requires a flag(-fPIC) to recompile ffmpeg, it's a > compiler flag, not a link flag. The error also shows it is for an assembly source file, for which C compilation do not apply. > On Tue, Sep 12, 2023 at 5:22 PM Reindl Harald > wrote: Top-posting is forbidden on these lists. If you want help, stop doing it; look it up if you need. Regards, -- Nicolas George ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Write audio volume info to file
Alexander Bieliaev via ffmpeg-user (12023-02-16): > At best, I would like to get an average audio volume. The problem with > using the volumedetect filter for me is that I'm using the ffmpeg library > for c# Condolences. > and I can't see the ffmpeg console output, Install a custom log handler. I grant you there is a need for a better API to extract data from filters. But volumedetect is fast but inaccurate. ebur128 can set up metadata to return the volume. > so I want to write data to a file. Redirecting outputs is system programming, it is not related to FFmpeg. > On Thu, Feb 16, 2023 at 1:44 PM Michael Koch > wrote: Top-posting is forbidden on FFmpeg lists; if you do not know what it means, look it up. Regards, -- Nicolas George ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Resizing ffplay window with fixed aspect ratio
Ferdi Scholten (12022-12-23): > Start ffplay with the -noborder option Starting ffplay with -noborder causes the window to not be resizable at all. It does enforce the window keeps its aspect ratio, but only to the amount that amputating your leg would get you rid of a plantar wart. -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Piping from FFmpeg to FFplay
Michael Koch (12022-11-13): > I can't find - without any following characters in the FFmpeg or FFplay > documentation. This is not specific to FFmpeg: https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap12.html#tag_12_02 Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] ffserver
Dave Blanchard (12022-11-08): > Are you seriously asking me this? What a stupid question. I hope you do not expect getting help with that kind of attitude. To vent your frustration, please go elsewhere, this list is not made for that. (I suggest you prefer a therapist over violence towards people around you.) I would also suggest you use a mail software that does not break threads, but it will not matter much anyway. -- Nicolas George ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] encode to RAW video
Clay via ffmpeg-user (12022-11-02): > Doesn't this serial ordering of the same command (-c:v ) twice just > drive cpu workload up for no actual benefit? > > To clarify: executing -c:v and then executing -c:v just > causes one output: . Thus you are forcing the CPU to > decode:encode:decode:encode rather than just decode:encode can > someone confirm or correct me here? No, except for the ridiculously negligible CPU workload necessary to process the option itself. ffmpeg does not have the infrastructure to make multiple decode-encode cycles, what you describe is not possible on top of being useless. What happens is just that the second -c:v option will override the first one. Regards, -- Nicolas George ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] concat, "Too many invisible frames"
Emanuel Berg (12022-08-21): > >> ffmpeg \ > >> -i $src1 \ > >> -i $src2 \ > >> -filter_complex "[0:v] [0:a] [1:v] [1:a] concat=n=2:v=1:a=1 [vv] [aa]" \ > >> -map "[vv]" \ > >> -map "[aa]" \ > >> $dst You are on the right track. > > Now OTOH it seems to be the resolution :) And possibly other > > errors as well ... > > > > [Parsed_concat_0 @ 0x55f3df730c80] Input link in0:v0 > > parameters (size 1920x1080, SAR 1:1) do not match the > > corresponding output link in0:v0 parameters (640x480, SAR 1:1) Read the error message: your inputs do not have the same resolution, you need to insert filters (scale, pad, crop, whatever you want) between the inputs and the concat filter. > The other method on that page [1] also don't work on these > files what I can see/implement ... (?) > > $ ffmpeg -y -i $src1 -c copy -bsf:v h264_mp4toannexb -f mpegts $dst1 > > [h264_mp4toannexb @ 0x55c9452bcc80] Codec 'vp9' (167) is not > supported by the bitstream filter 'h264_mp4toannexb'. > Supported codecs are: h264 (27) Again, read the error message: you are applying a method specific to H.264 to a VP9 stream. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] concat, "Too many invisible frames"
Emanuel Berg (12022-08-20): > o/ > > I try to concat two webm files and get > > Too many invisible frames > > The files have different resolutions, is that why it fails? > If so, how do you then "normalize" them before concat'ing? > > If it isn't that, then why? I suspect some formats just have too complex features to allow for simple concatenation. concat is not guaranteed to work with streams that have different parameters. There is no way around that without transcoding. To normalize, use the concat filter and transcode. Sorry I cannot be of more help. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] concat audio files
Michael Koch (12022-06-11): > I always get this error message: > Stream specifier '' in filtergraph description [0][1]concat=n=2:a=1 matches > no streams. Where did you find this "[number]" syntax, and has it ever worked for you? Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] ffprobe does not render sdes tag field properly
Robin van der Linden via ffmpeg-user (12022-06-03): > After stealing the Tesseract in \"Avengers: Endgame,\" Loki lands before the > Time Variance Authority. This looks like escaping of a character that has a meaning in the surrounding language, a completely different issue than the issue of international characters. But you did not tell how exactly you get this output, so I cannot say more. I suspect you are missing a lot of theoretical background necessary to achieve your goals. > Am 2022-06-03 11:36, schrieb Nicolas George: Top-posting is forbidden on this mailing-list; if you do not know what it means look it up. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] ffprobe does not render sdes tag field properly
Robin van der Linden via ffmpeg-user (12022-06-03): > It seems that ffprobe does not render special characters the right way for > that field. ffprobe does not do any rendering, it writes the text to its standard outputs, the task of rendering falls on whatever program is connected to the outputs. It seems your problem is that your terminal does not work in UTF-8. But you did not say which terminal you use, so I cannot help further. Regards, -- Nicolas George ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Multiple parts of a video
Cecil Westerhof via ffmpeg-user (12022-05-29): > I am going to ignore you. Then I am going to ignore you. > Before I CAN USE concat I have the create the n cuts I need to put > into the concat. And it is easy to do. But do not count on my help. -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Can ffmpeg calculate the min and max bitrate of a video?
smu johnson (12022-05-03): > ffprobe / ffmpeg can show a video's avg. bitrate easily enough but I would > like the option for ffmpeg to scan an entire video file (if need be, I > don't think this info is stored anywhere) to find out the lowest (min) > bitrate of a video stream as well as the highest (max) bitrate it uses and > print them. ffprobe can print for you the size and timestamp of each packet. From that, you can compute what you want. Note that since the video is made of frames encoded as packets, a discrete series, there is no such thing as an instantaneous bit rate in which you can search a min and max: instantaneous bit rate is a derivative, derivatives are continuous beings. What exists is the average bit rate over a short period, the shortest being the duration of a single frame, and the corresponding bit rate the size of the corresponding packet divided by said duration. But that would be full of noise. For a less noisy and more relevant information, you would need to make an average over an interval containing at least one I-frame. The last two paragraphs were not about FFmpeg, they were math. I am not on this mailing list to teach math. > This has been asked on Stack Exchange before by someone else here: > https://video.stackexchange.com/questions/21661/is-there-any-ffmpeg-command-for-knowing-max-bit-rate-of-a-video > . The only problem is people are suggesting running scripts and other > hacks in order to do this instead of ffmpeg being able to just do it itself. And they are perfectly right. For specific and unique needs, scripting your own solution is infinitely superior to knocking on wood in the hope somebody already implemented exactly what you want. > I'm on Windows 11 so I don't know how easy it would be to run these scripts You can find a solution to this issue there: https://www.debian.org/ > others wrote and I'd rather get an official answer from ffmpeg instead of > some script that might not even work properly or give me accurate > information. I hope it is clear for you: you should not run a script you found on a random web site, it would be a huge security risk. You need to understand the script and adapt it to your needs. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Extracting forced subtitles from a DVD.
Michael Mueck via ffmpeg-user (12022-04-28): > In addition to the question below about the wrong subtitle track > ending up in the output, I've also been looking into dvd2concat (which > it looks like you wrote!). I was able to use it to make file.concat, > but I'm having some trouble figuring out what to do with that file. > I'd very much appreciate you pointing me in the right direction. > Thanks! The script is self-documenting: NAME dvd2concat - create a concat script for a DVD title SYNOPSIS tools/dvd2concat *path/to/dvd/structure* > *file.concat* DESCRIPTION This script uses lsdvd to produce concat script for a DVD title. The resulting script can be used to play the DVD using ffplay, to transcode it using ffmpeg or any other similar use. *path/to/dvd/structure* is the path to the DVD structure hierarchy; it normally contains a directory named VIDEO_TS. It must not be encrypted with CSS. *file.concat* is the output file. It can be used as an input to ffmpeg. It will require the -safe 0 and -protocol_whitelist file,subfile,concat options. Then you need to peruse the documentation about concat scripts: https://ffmpeg.org/ffmpeg-all.html#concat-1 > > On 2022.0428, at 16:19, Michael Mueck wrote: Please remember that top-posting is strictly forbidden on this list. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Extracting forced subtitles from a DVD.
Michael Mueck via ffmpeg-user (12022-04-28): > I have decrypted and ripped all of my DVDs into individual VIDEO_TS > structures for just the main movie or an individual TV episode. Each > move or TV episode consists of a VIDEO_TS folder containing the > original uncompressed > VIDEO_TS.IFO, VTS_01_0.IFO and VTS_01_[1->N].VOB files. This is already wrong. The VOB files do not map directly to the video parts of the contents. If you do that, you will get also all the menu crap in your resulting file. Also, the subtitles palette is not in the VOB files. You can generate a concat script to access the DVD hierarchy correctly using the dvd2concat script in the tools directory. It is entirely possible that doing so would fix your issue. Also, do not re-encode the subtitles, use -c copy, it will be more reliable. Regards, -- Nicolas George ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Decoder output: Samples or renders?
markfilipak.nore...@gmail.com (12022-04-11): > Hello, > > I trust this question will be trivial, but I've not found the answer -- I've > searched (and have tried to look at source) for a long time. I'm trying to > document from a global viewpoint and determine at what point decoding ends. > > Do decoders output reconstituted samples (e.g. 720x576) or renderings (e.g. > 768x576 or 1024x576)? Is this for your book? Are book not supposed to be written by people who know or who know how to find out? How can anybody trust anything you write if you are not capable of testing this very simple question by yourself? (These are rhetorical questions.) -- Nicolas George ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] drawtext reload=N > 1?
Gyan Doshi (12022-02-28): > This has come up before. I'll patch it to make it an interval. I do not think it is worth your effort: the cost of loading the file is negligible compared to the rest of the operations. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] how to avoid broken pi
meex (12022-01-26): > in a bash script i'm using ffmpeg to create a spectrogram movie and pipe the > output to a decoder (mpv in this case, but it doesn't matter) > > as expected, if the user exits mpv before ffmpeg completes, it returns a > broke pipe error and i would like to avoid that if possible > > the problem is that the terminal may refuse to accept any user input when > this happens (this occurs ~20% of the time) This is not a problem with ffmpeg. You should configure your shell to set the tty to a sane state before a prompt. With zsh, it is done with "ttyctl -f". > is there a way to have ffmpeg exit gracefully when the pipe is broken? Again, it is not ffmpeg's responsibility: Compare: ssecem ~ $ sh -c "dmesg" | head -n 1 [0.018123] On node 0, zone DMA32: 1580 pages in unavailable ranges zsh: exit 141 sh -c "dmesg" | zsh: done head -n 1 ssecem ~ $ sh -c "trap '' PIPE; dmesg" | head -n 1 [0.018123] On node 0, zone DMA32: 1580 pages in unavailable ranges dmesg: write error zsh: exit 1 sh -c "trap '' PIPE; dmesg" | zsh: done head -n 1 Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Removing parts of a video using the select filter
Simon van Bernem via ffmpeg-user (12022-01-08): > Hi, > I am trying to remove parts of a video (with audio) using the select > filter. I constructed this command to remove seconds 20-25: > > (newlines only for readability) > > ffmpeg -i input.mkv > -vf "select='1-between(t,20,25)', setpts=N/FRAME_RATE/TB" > -af "aselect='1-between(t,20,25)', asetpts=N/SR/TB" output.mkv > > This works great, except that when I use multiple "between" clauses > to discard multiple sections, audio and video will start to get out of > sync. The select filter is very generic, and therefore not very robust. It does not update the timestamps, hence the need to update them afterwards. Furthermore, it works with whole frames, which can accumulate for audio. For your use case, consider the segment and concat filters. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] 5.1 + stereo
Hanna Frangiyyeh (12022-01-03): > I have a video file and audio file. The audio file has 5.1 + stereo. The > stereo audio is on channels 7&8. > Is it possible to take the stereo tracks(7&8) and put them on the video > file as stereo channels 1&2. If so, how to accomplish this? The pan filter can do that easily. https://ffmpeg.org/ffmpeg-all.html#pan-1 Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Alternative to Dynamic Text
Gyan Doshi (12021-11-09): > Not on FAT32. And since it's not guaranteed, the filter should accommodate > that. What are you talking about? The filter does not write the file, it just reads it. It is the responsibility of whoever writes the file to ensure that the writing does not overlap with the reading. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] toggle between two streams
Michael Koch (12021-09-03): > ffmpeg -loop 1 -i 1.png -loop 1 -i 2.png -lavfi sendcmd=c="0 [expr] > streamselect map 'gte(mod(T,2),1)'",streamselect=map=0 -t 10 -y out.mp4 > > Unable to parse graph description... You need to put the proper amount of backslashes to protect the commas. I will grant you it is not intuitive and very annoying, but it always can be made to work. -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Decimal times to frame numbers
Gyan Doshi (12021-08-21): > A nit, but MP4 is inherently VFR-ready - that's what the (mandatory) stts > box is for. > > It is for some opaque reason that the muxer defaults to CFR, possibly to do > with some limitation or bug in the early days. Good to know. I will still argue that MP4 is a crappy format designed with more concern for pleasing big investors than with concern for good design. For careful examination of the output, NUT would be the most reliable. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Decimal times to frame numbers
amindfv--- via ffmpeg-user (12021-08-20): > I then tested the output of running commands like this, only changing the > value for $STARTTIME : > > export STARTTIME=0.33 ; ffmpeg -r 24 -i color-frames.mp4 -r 24 -ss > $STARTTIME "test-$STARTTIME.mp4" There are several flaws in problem report: - You did not post the full output. We need the full output to spot some usual missteps. - You do not need export since you are using the variable directly. - By adding -r on your input, your force ffmpeg to re-synthesize the timestamps. This is wrong in general. In this particular case, it changes the precision of the timestamps: your input file has a 1/12288 time base, with -r 24 it becomes 1/24. - By adding -r on your output and by using a format like MP4 that only supports constant frame rate, you are forcing ffmpeg to duplicate or drop frames to a certain rate. If you want to examine the output carefully, either use a format that supports arbitrary timestamps or do not use a format at all and write to individual images with "-vsync passthrough". It is possible you have unearthed an off-by-one bug somewhere. But in general, the logic should be: - The timestamps you write are rounded to the nearest integer multiple of the time base. - The frames you get in the filter line are exactly the interval you requested. That means if the time base is more precise than the frame rate you can get frames with half the duration. What happens after the filter chain, on the other hand, is subject to more complex heuristics. I strongly suggest you try to work as much as possible only with filters. > On Wed, Aug 18, 2021 at 09:26:03PM -0600, amindfv--- via ffmpeg-user wrote: Top-posting is forbidden on this mailing-list. Do not do it again if you want help. Look it up if you do not know what it means. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Decimal times to frame numbers
amindfv--- via ffmpeg-user (12021-08-18): > Is this the best way to think about the decimal seconds<->frame number > conversion? No, it is the other way around: you should not be thinking about frame numbers, you should be thinking about timestamps. Timestamps are an inherent property of the frame, they will be preserved or converted by filters and storage. Frame numbers are not. If you have an issue with timestamps, please be more specific about it, there is no doubt it can be solved. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] How to lossless crop mp4 videos
Ulf Zibis (12021-08-16): > if I understand correct, mp4 videos are encoded in blocks of 16x16 > pixels. I I'm wondering if I could crop a video by multiples of 16 > pixels without reencoding the remaining blocks. It depends on the codec, not the format. With a codec like MJPEG, it is possible. There are tools to do it with individual images, look up jpegtran. But with video codecs that use temporal compression, a visible part of the next image can depend on a cropped part of the current image, and that makes it impossible. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
[FFmpeg-user] "proto,,option...,,:" feature
Hi. Is somebody here using the "proto,,option...,,:" feature? I am considering removing it. If you do not know what I mean, do not bother, it means you do not. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] -pix_fmt + pixel format conversions
Green Koopa (12021-07-30): > Thank you, that helps my understanding. Is there a way to know what > pix_fmts each filter can accept? Unfortunately, nothing public, unless I am mistaken. If you have a build tree, you can try running the filtfmts tests, and then re-run the test program directly to see its output. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] -pix_fmt + pixel format conversions
Green Koopa (12021-07-29): > My input file is yuvj420p(pc, bt709). My target output is > yuv420p(tv, bt709). I would like to use "-pix_fmt +yuv420p" > to specify the output format, and to force me to be explicit > in my conversions in the filtergraph. How do I achieve > explicit conversions? The format filter appears to trigger > implicit conversions. The format filter does not do the conversions, it only forces the format at a certain point in the filter graph. The standard filter for converting between pixel formats is scale. In certain cases, I hear zscale can be more suited, but I never looked at the specifics. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Problem with concatenating converted mkv files with changed sample rate
Mike Martin (12021-07-16): > Anyone any ideas what is happening? No. But you should not be concatenating after transcoding in the first place. Use the concat filter and encode everything once. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Modify i frame placement in videos
Jaeho Bang (12021-07-15): > I want to 'convert' originally chosen I frames to P frames because the > newly encoded video will be bloated in size if I end up keeping the > original set of I frames along with my new set of I frames. By the I->P > conversion there is the possibility that the newly encoded video > has smaller overall size. You are engaging in premature optimization. Just let the codec choose, it knows best, and "convert" the I-frame by understanding there is nothing to do. Then, if you have performance or size issues, come back. > On Thu, Jul 15, 2021 at 12:02 AM Nicolas George wrote: ... but learn what top-posting means, because it is forbidden here and you will not get useful help if you do it again. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Modify i frame placement in videos
Jaeho Bang (12021-07-14): > I was wondering if there is a way in ffmpeg to convert I frames to P frames. Why? > I would like to convert the I frame at 200 to a P frame, so as a result we > have 4 I frames. Why? While it makes sense to want an I-frame instead of a P-frame, because there are things you can do with an I-frame that you cannot with a P-frame, the symmetric does not apply: an I-frame is functionally a P-frame, just one that only has new blocks. So, before you ask how to do it, you need to explain, possibly to yourself, why you think you need to do it. Odds are you will realize your exact need is somewhat different. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Click-activated Stream Recording
S. Helbig via ffmpeg-user (12021-07-12): > I'm wondering if there is a way for FFMPEG to handle click-activates > streams. I'm just experimenting at the moment. You are asking if FFmpeg contains a JavaScript engine. The answer is no. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] How to check if a youtube URL is valid before starting download?
Carl Zwanzig (12021-07-09): > In idiomatic English, it means to start with the simple, not with the complex. Thank you very much. > This sounds like one of those places where cobbling something together out > of command line programs is an exercise in frustration and the time might be > better spent on working with the source code and libraries to get something > that does exactly what you want. Or at least reading the source code to see > what messages come from where. That would be trying to fly ;-) I'd rather suggest getting a good book or course on Unix shell, file descriptors, redirections, etc., and come back to FFmpeg once this aspect of the issue is no longer a problem. For example, anybody skilled enough can tell that the reason "... 2>&1 > freezeoutput.txt" produces an empty file is that the order of the redirections matters. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] How to check if a youtube URL is valid before starting download?
Christian Ebert (12021-07-09): > But for writing the log into a file look into ffmpeg's -report option, that's > what it's for. You can use it that way, but it is not what it is for. My advice for this thread: don't try to run before you can walk. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] JPG/PNG images render in incorrect orientation in MP4 output file and can't be combined in same MP4 video
Mark Dougherty (12021-07-08): > ffmpeg -hide_banner -f concat -safe 0 -I test-ffmpeg.Txt -c:v libx264 -r 30 > -pix_fmt yuv420p test-ffmpeg.mp4 You should not be using -hide_banner if you want help. You should not be using -f concat if you are transcoding. > I can't mix both JPG and PNG image files in the same input text file. That is normal: # All files must have the same streams (same codecs, same time base, # etc.). Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] 4K Way to large to stream
Carl Zwanzig (12021-06-29): > Like the "Good/Fast/Cheap - Pick two" metaphor, you have hit the > quality/file-size/bandwidth trade-off. To keep the resolution at 4k and at > good-to-excellent quality, perforce the files and bit-rate will be large- if > you want the file to be smaller, even with very fancy encoding something > must be discarded, could be resolution, could be frame rate, could be > "quality". Frame rate and resolution are both elements of quality. In principle, codecs are capable of skipping frames or flattening neighboring pixels, so they should be able to decide to reduce the frame rate or resolution if it is the best choice. But in practice, codecs are not that smart, and reducing the resolution will sometimes help. > There's also the point that in many cases, super high quality is effectively > wasted, for instance, 4k is only effective if the viewer has a 4k display; ... and excellent eyesight: for a normal/close viewing distance, the separation power of the central area of our eye is about the size of a pixel in a 2K video. Everything beyond that is only useful if we pause and look closely. > 5.1 sound is only effective if the listener has 5.1 playback equipment -and- > the sound was mixed for that. etc. This is true. But you also missed something: It is true that, unless we're using "-c:v kenjanoishi", in order to gain something, for example file size, we have to sacrifice something of equal value, and it is frequently quality. But there are other possibilities than quality. Compatibility is a possibility: the old file was playable by a DVD+DivX player from the 2010s, the new file is not, but it is smaller. Using a better codec or a more complex codec profile is a case of this. Processing power is a possibility: the old file took 2 hours to encode, the new file takes 10, but it will be smaller. Nimbleness is a possibility: the old file allowed to seek at any half second, the new file only allows to seek to scene changes, but it is smaller. This is something to remember. Video encoding is a complex task. Your advice was sound: for archival, better keep the original. Do not recompress to gain a measly 25%. But for viewing, adapt the quality compromise to the viewing conditions. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] 4K Way to large to stream
rbar...@njdevils.net (12021-06-28): > I did a 10 sec preview from the middle of the file. It is very grainy. Is It was expected. You cannot have both a small file and perfect quality, I hope you realize that. > the -s 384x160 the output Frame Size? You have not perused the documentation as I urged you. > I think that would be way too small for a 4K video convert. There is no such thing as too small for a convert, there is only what you want to do. Which you neglected to state. And probably to think about. Start with that. > -Original Message- Please remember that top-posting is forbidden on this list. Look it up. You are unlikely to get further useful help if you do it again. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] 4K Way to large to stream
rbar...@njdevils.net (12021-06-28): > ffmpeg -i Family_Fun.mkv -c:v libx265 -crf 26 -preset medium -c: aac -b:a > 128k Family_Fun.mp4 > Can someone offer a better script than what I'm using. Just add "-r 5 -s 384x160" before the output file name. It should produce a much smaller video, and finish much faster too. Of course, I urge you to check the result to see if it matches your expectations. And to peruse the documentation to see what these option would do before doing it. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Audio out of sync after video concatenation
ibur...@compuscience.com (12021-06-22): > Video 2 - 4 seconds without audio (I generated this video using xfade > transition Only use the concat demuxer with original compressed streams. If you need to concatenate the result of other processing, do not encode them and use the concat filter. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Python / Qprocess misfires commands.
Moritz Barsnick (12021-05-18): > Sure. I don't understand QProcess (yet, or anymore), so I have no idea > what to debug. I don't know what to make of the return code 6 either. That could be a signal number incorrectly interpreted as a return code. That would make the signal probably SIGABRT, and therefore probably the sign of a failed assert. It is almost certain more diagnostic appears in ffmpeg's output. I do not know if Qt allows to capture it, but it would be unforgivable not to. Anyway, the ffmpeg-user mailing list is not the place to learn Qt programming, nor generic system programming. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] “Real Time”, “Slow Motion” and “Time Lapse”
Bryce Newman (12021-05-10): > I have - for example - three videos that which visually can be classified as > “Real Time”, “Slow Motion” and “Time Lapse”. > My understanding is the speed of the video is controlled by the filter PTS. Your understanding is very inaccurate. PTS is not a filter, it is a property of each frame, the instant it is meant to be displayed. The setpts filter can be used to alter the frames' PTS, resulting in changes of video speed. > Below are three ffprobe outputs; “Real Time”, “Slow Motion” and “Time > Lapse”. The PTS for “Slow Motion” seems easy to detect using the PTS > value. > The “Real Time” and “Time Lapse” appear to have similar PTS values. No, absolutely not. What you are seeing is the difference in frame rate: 24 fps (from NTSC, actually 24/1.001), 25 fps (from PAL) and 30 fps (from NTSC, actually 30/1.001). > My goal is to be able to accurately detect if a video is “Real Time”, > “Slow Motion” or “Time Lapse” within the first 3-5 seconds of the > video. > I know portions of the video can change from “Real Time”, “Slow > Motion” or “Time Lapse” and that is ok and we may classify them as > all-the-above. > > What is the best way using ffprobe to detect if the first X seconds of > a video is “Real Time”, “Slow Motion” or “Time Lapse”? You cannot expect software to be able to distinguish contents that was slowed down from contents that was slow in the first place. What you are asking has the same kind of difficulty than https://xkcd.com/1425/'s check whether the photo is of a bird. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Odd video output, playing RTSP on RPI
schrotty (12021-05-02): > when i say "headless" i mean raspbian lite , without desktop. This is what people call "text mode" or "console". Headless is when there is no screen at all. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Decklink timestamp_align, what should it do?
Bouke (12021-05-02): > Ok, but what is ' UTC modulo’ ? An incomplete formula. Like "UTC minus": UTC minus... what? UTC modulo... "UTC modulo timestamp_align", as a whole. Then read: https://en.wikipedia.org/wiki/Modulo Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Possible to change pitch of audio in a downloaded mp4 file?
Bo Berglund (12021-04-29): > I did NOT want to change the *speed* of neither the audio nor the video! Maybe that was not what you WANTED to do, but that is what you did. You used atempo, the name is quite clear, it changes the tempo. And if you do not trust the name, trust the documentation: "Adjust audio tempo.". Compare to what was suggested to you: >> Yes, this is possible with a combination of asetrate, atempo and >> aresample filters. You need to start paying attention. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Possible to change pitch of audio in a downloaded mp4 file?
Bo Berglund (12021-04-28): > OK, that included the video... > But now there is no lip-sync at all. Seems to drift longer apart during the > video playing. Audio and video running at different speeds. You changed the speed of the audio and not the video, what did you expect? FFmpeg does what you tell it to do, it cannot read your mind. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Credit Notes (bulk creation)
Adrian Perello Marin (12021-04-28): > I receive about 100 videos, with a CSV file containing the credits of > the video; and I have to convert the text in each of the videos to > play at the beginning or at the end of the video. Is it possible to do > this by command line so that it reads the content of the CSV (video > name and credits text) and processes them in a "more or less" > automatic way? Not with FFmpeg directly. But FFmpeg is a command-line tool, it plays well with other command-line tools. You just need to learn how to use them. -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] How to filter time dependent
Michael Koch (12021-04-23): > The crop filter could be used to change the x,y coordinates, with constant > output resolution. With timeline? Please elaborate? Regards, -- Nicolas George ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] How to filter time dependent
Gyan Doshi (12021-04-23): > Strictly, it's supported via -noautoscale (which you reviewed), but it's > not supported by (almost) any encoder. No, it is not *supported*, it is a fragile hack. *Supporting* resolution changes will require a lot more work. Regards, -- Nicolas George ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] How to filter time dependent
Ulf Zibis (12021-04-23): > I already had checked that. Unfortunately, crop has no timeline support: How would that work? Enabling or disabling crop changes the output resolution, which is not supported by libavfilter. Regards, -- Nicolas George ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] repair missing audio header
Carl Eugen Hoyos (12021-04-19): > Why do you believe that the error message is an issue? Because if there is no issue, there should be no error message. A warning can be a false positive. An error message should never be. > want to fix the error message, fixing in this case of course > means to completely remove a broken audio frame. Certainly not. Fixing in this case means creating a frame packet that would decode into the same PCM data while not triggering the error. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Plotting Circles and labels on individual frames of a movie
Rainer M Krug (12021-04-08): > I have found “draw_text” > (https://ffmpeg.org/ffmpeg-filters.html#drawtext), but I have no idea > how I could do this. We can assume that I have a text file with the > following columns: > > FRAME: the frame on which the labels and circle should be plotted > X: the x-coordinate > Y: the y=coordinate > LABEL: label for the point > > Also possibly important, there are multiple (many) particles for which > circles and labels need to be plotted on each frame. This looks like something ASS subtitles can do easily. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] How to dynamically drop frames as required to keep transcoding real time?
Adrian Cable (12021-04-08): > Mark – yes – you’re understanding exactly right! I was thinking > specifically of the encoder ‘throttle’ being a frame rate control, but > other forms of quality control that could be self-adjusted by the > encoder to keep up with the input would also work for me. > > I did look through the history here but couldn’t find anything quite > applicable. I do appreciate you taking the time to understand my > issue! Hopefully someone who has direct experience of how to achieve > this will read this as a result and be able to help. You realize that you are wasting your time by ignoring Carl Eugen's authoritative answer, right? If you want real help with your problem, start by stopping your top-posting. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Cut part of a video, crop it and blackout parts of it
Carl Eugen Hoyos (12021-04-05): > There is a fundamental misunderstanding: > You decide how much quality you want to preserve, x264 decides how > much bitrate is needed to reach that quality. You also decide how much computing power you want to spend on it, which Cecil neglected to do. More computing power usually means lower bitrate for same quality. The keyword is "preset". Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] 1080i AVC-I 100 frame rate conversion
Phil Rhodes via ffmpeg-user (12021-03-29): > Are you contending that there is no such thing as video at 24000/1001 fps? Are you capable of understanding a simple phrase made of less ten words? -- Nicolas George ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] 1080i AVC-I 100 frame rate conversion
Phil Rhodes via ffmpeg-user (12021-03-29): > What? I have nothing to add to what I have written. Get a clue. -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] 1080i AVC-I 100 frame rate conversion
Carl Zwanzig (12021-03-29): > It's an artifact that is still used. Moreover, I've never met an broadcast But it has nothing to do with movies. Unless movie studios have started adding this factor on purpose. > engineer who didn't write 29.97 or 23.97 (or "30fps drop-frame"); I think > this is the only place I see things like "3/1001". Yeah, engineers are no mathematicians. Their bad. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] 1080i AVC-I 100 frame rate conversion
Phil Rhodes via ffmpeg-user (12021-03-29): > For the sake of being really rigorously correct, yes, 24.0 or 24000/1001. Once again, you are wrong. The 1000/1001 factor is an artifact of color TV. -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] 1080i AVC-I 100 frame rate conversion
Carl Eugen Hoyos (12021-03-29): > Either you are showing content where the speed (and duration) can be > changed but this does not matter - such content is rare but likely > exists You mean that most movies from the NTSC area sold as PAL DVD likely exist? I can confirm, they exist. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Some Questions on Time Delta between Frame Display and Frame Capture. Thoughts?
Hassan (12021-03-22): > What are better approaches to address this problem? I think you need to take a step back. You have your nose on a specific issue, but you have neglected to explain the big picture: what are you trying to achieve that requires that level of accuracy? Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] How to get he total number of frames
Peter White (12021-03-12): > but that is because a packet needs to be decoded first to get the frame. Please be complete in your statements: ... with some obscure codecs or if libavcodec happens to have been compiled without parsers... Otherwise counting the packets is perfectly fine, as I have already explained. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] How to get he total number of frames
Ulf Zibis (12021-03-09): > So for correctness, ffmpeg should report packets instead frames in its > progress output line, at least with -c copy ... or please correct me. Would you insist on people saying that the mailman brings envelopes instead of letters too? Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] How to get he total number of frames
Peter White (12021-03-09): > I have now, but it returns 'N/A'. Now that I see that, I might have > tried it way back when, even, and have forgotten about it. > > ffprobe -count_packets -select_streams v:0 -show_entries stream=nb_read_frames ^^^ ^^ Regard, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] How to get he total number of frames
Peter White (12021-03-09): > Is there a meaningful difference in this context? The fact that you need to ask is proof enough that it is needed. > Now we are getting somewhere. No, I have not, because I did not know it > can do that. But above question remains: does packet count always equal > frame count? What might be pitfalls with this approach? The frame count could be different than the packet count with some codecs, indeed, but I am not aware of any specific case. Anyway, using -c copy gives the same result. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] How to get he total number of frames
Peter White (12021-03-09): > Would you mind answering the OP's question with a command line example, > then? I help people who help themselves, thus avoiding Russel's paradox. > I am well aware of that, but nobody said anything about parsing. Oh? Please, explain to me how you extract the number of frames from the statistics line without parsing it? > ffprobe -v error -count_frames -select_streams v:0 -show_entries > stream=nb_read_frames -of default=nokey=1:noprint_wrappers=1 input.mkv Do not use "-v error" if you want help. > > No need for output because it takes to long to complete: roughly one > minute for a 20 minute video as opposed to virtually no time with: > > ffmpeg -i input.mkv -an -sn -c copy -f null - -c copy tells ffmpeg to dispense with the decoder, which means it does not count frames but packets. Have you tried telling ffprobe to count packets? Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] How to get he total number of frames
Peter White (12021-03-09): > Sorry, I didn't mean to offend. I was not offended, I was amused. > Is there a proper universal way to do this with ffprobe that does not > take ages to complete? Honest question. Of course. As I already said, FFprobe can do the same thing as FFmpeg, but its output is meant for parsing. Your solution will break as soon as we change a tiny detail in the statistics line. Show us your complete command line and console output if you have trouble. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] FFmpeg list footer
mX (12021-03-09): > Can someone with list admin access (admins at foot of this email) > please update the footer for this mailing list to assist new posters - > because few people read the list FAQ and the devs and regulars spend > too much time reminding posters of the list rules. I'm suggesting the > following but please discuss: > > > > . Do not top-post i.e. reply *below* last thread message. > . Include complete terminal command/all information. > . Include uncut console output (trim excess/repeating lines). > . Upload sample video to public servers and include a link. > . Delete all footers, sigs, other junk before replying. What makes you think the people who do not read the list guidelines and FAQ will read the list footer? Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] How to get he total number of frames
Peter White (12021-03-09): > Unless it happens to be one of those special cases that don't have that > info in their metadata, like matroska: Did I suggest to limit to the output of -show_format or -show_streams? If you want information about frames, guess what you should use? > Other than being a little ugly, my way seems to yield the correct result > with any video. I like universal solutions, so I stuck with it, and > recommended it. FFprobe yields the correct result, and in a cleaner way. Just use it properly. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] How to get he total number of frames
Peter White (12021-03-09): > If anybody on this list knows a better one, step up, please. ffprobe, of course. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] swr_convert from packed to planar
Livio Tenze (12021-03-07): > Is it possible to use swr_convert to resample and convert audio > samples from AV_SAMPLE_FMT_U8 to AV_SAMPLE_FMT_FLTP? ffmpeg -lavfi 'sine,aformat=sample_fmts=u8,aformat=sample_fmts=fltp' -f null - ... obviously yes. See this list for questions about the API: https://lists.ffmpeg.org/mailman/listinfo/libav-user/ And if you expect help, you need to provide a modicum of information. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Unable to sync audio and video
Livio Tenze (12021-02-23): > I am following your suggestion. I added one thread to acquire the audio > stream. Currently I have only the thread for the audio stream; I will > implement threads also for video acquisition. > The see a strange behaviour: > === > Crop frame system is 1 > Dummy read one frame > VIDEO PTS START from video1 > AUDIO: void AudioInputThread::startLoop() > AUDIO: audioThread started NOW! > PTS START video: 83565572 audio: -1 > stream v:1/15360 a:1/22050 > AUDIO: audio: 0.000 0.185759 = 0.186 1614099985303395 > set record for 15.00 minutes > AUDIO: head 0, tail 1 > start recording > AUDIO: audio: 1.840 0.185759 = 2.026 1614099987143524 > AUDIO: head 0, tail 2 > AUDIO: audio: 2.068 0.185759 = 2.253 1614099987371002 > AUDIO: head 0, tail 3 > AUDIO: audio: 1.735 0.185759 = 1.920 1614099987037933 > AUDIO: head 0, tail 4 > AUDIO: audio: 1.476 0.185759 = 1.662 1614099986779509 > AUDIO: head 0, tail 5 > AUDIO: audio: 1.293 0.185759 = 1.479 1614099986596620 > AUDIO: head 0, tail 6 > AUDIO: audio: 1.116 0.185759 = 1.302 1614099986419398 > AUDIO: head 0, tail 7 > video1: 0.032 83597620 3 > >>> video timer0 0 > >>> video timer1 20 > === > Please, take into account lines starting with "AUDIO: " tag. > This is a log of my application. I notice that the audio estimated position > (it is estimated taking into account the first received pts) starts > increasing, then decreases, and, after some packets, the behaviour is > monotonic and right. Moreover, the distance from the starting PTS and the > second one is almost 2 seconds. > Have you any suggestions about this strange behaviour? I am sorry, but I do not think I can help with that: I have no idea what these numbers are supposed to mean. In the meantime, I notice that you have not checked if you had buffer overruns in ALSA, and that you have not determined the origin of your timestamps. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Unable to sync audio and video
Livio Tenze (12021-02-17): > No, it is not, because the audio and the video streams come from two > different sources: one webcam and an external microphone. The starting PTS Different sources do not mean different timestamps origins. In fact, you NEED the same timestamps origin if you want to sync. > values are different for two audio and video sources. How should I get the > same origin with this configuration? Please suggest how to treat this case. Ideally, the documentation of the device you are using should be stating it. For example: http://ffmpeg.org/ffmpeg-all.html#video4linux2_002c-v4l2 "Depending on the kernel version and configuration, the timestamps may be derived from the real time clock (origin at the Unix Epoch) or the monotonic clock (origin usually at boot time, unaffected by NTP or manual changes to the clock)." Unfortunately this is rather the exception than the norm. If the documentation does not say it, then you need to experiment: actually look at the timestamps, look at at the actual time when you capture, do some arithmetic to find the origin, and try to guess what it corresponds to. And then propose a patch to document the origin of timestamps for that particular device. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Unable to sync audio and video
Livio Tenze (12021-02-17): > > That should work, provided you checked that your timestamps relate to > > the same origin. If some timestamps relate to the system boot and some > > to 1970-01-01, you will get a desync. > > The timestamp I am currently using is related to the pts obtained from the > AVPacket packets: I use the first PTS packet as reference. Is it a right > approach for syncing? It is the only right approach. But you have not answered the question: have you checked that the timestamps of both streams are relative to the same origin? > I haven't found info about this issue: does the av_read_frame call return > always the latest acquired packet or does it return a buffered packet? I > haven't found this info. The question is related to real-time acquisition. av_read_frame() will not skip packets. A device driver may skip data, but you should try to avoid it at all costs. > Ok, thank you for this suggestion. Do you suggest to use one thread for > every source and one thread for encoding? Is it a good approach in your > opinion? For devices, running each in its own thread is probably the most reliable solution. At least until we have a proper event loop. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Unable to sync audio and video
Livio Tenze (12021-02-16): > At the moment I have only one thread (the main one, as in doc/examples). > The process I implemented is the following: > 0) Initialize PTS output frame (one PTS for video and another for audio) > 1) check PTS difference between PTS video and audio > 2) if ptsvideo>ptsaudio then decode one video frame, and encode it in the > output stream > otherwise decode audio frame, and it in the output stream. > 3) go to point 1 That should work, provided you checked that your timestamps relate to the same origin. If some timestamps relate to the system boot and some to 1970-01-01, you will get a desync. Plus, if the capture did not start at the same time, you will get extra frames at the beginning of a stream, and it is possible that some players will not catch up or catch up slowly. It would probably be more reliable to discard frames captured before the first frame of the other stream. > > Do the timestamps between audio and video match before encoding? > Yes, please check above. I use two PTS values: one for audio and one for > video. The PTS from the input stream differ from the ones of the output > stream. I check the distance between the first packet.pts and the current: > here I saw that strange behaviour where the audio elapsed time is very high > with respect to the video input stream. All you talk here is timestamps consistency within each stream. I was asking about timestamps consistency between the streams. > Do you think that this behaviour is due to missing multithread? I found the Yes. Without parallelism for the capture, the codec initialization could take so much time as to cause a buffer overrun in one of the capture drivers. > above flowchart in doc/examples where no threads are used. It is entirely possible this flowchart is not up to date or chose to gloss over implementations details that are not deemed relevant for the information expressed. The command line tool ffmpeg uses threads for inputs as soon as there are more than one. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Unable to sync audio and video
Livio Tenze (12021-02-15): > -The audio source comes from alsa: here I see really strange behaviour. The > pts value of the second packet with respect to the first pts packet seems > to be "delayed" from 0.4s to 1.8s. I don't understand this behaviour: I > checked the time from start to the second packet and the elapsed time > cannot be justified (ms and not s). Can you observe the same phenomenon using ffprobe? ffprobe -f alsa -i default -show_packets -of compact | head -n 50 | less -S would be a good way to look. Do you observe warnings on the console? How does your application handle parallelism between encoding and reading from devices? > -Finally, when I write audio and video in the output MP4 stream (I use > libx264 and libfdk_aac for video and audio respectively) the audio stream > is delayed. Do the timestamps between audio and video match before encoding? Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] "most insulting comment" [was: Re: Filter documentation -- PTSs]
Jim DeLaHunt (12021-02-14): > Oh, my dear Carl Indeed, you managed to be even more insulting in just four words and half an hour. -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Filter just the 1st audio channel of the input.
Marco Mircoli (12021-02-03): >wandering if it is possible to process just the 1st audio channel of an > input. > I don't know how many channels I will have as input, but I know that I have > to process just the 1st and the others I have not to considerate. > > INPUT from mono to multichannel > filters. > OUTPUT just one channel (mono) > > I've tried this but doesn't works > > ffmpeg -i FILE_FROM -map_channel 0.0.0 -af > highpass=f=70,adeclick,loudnorm=I=-16.5:TP=-1.5:LRA=7 FILE_TO Just use pan=mono|c0=c0 to extract the channel you want wherever you want in the graph. No need to completely split the channels, it was meant for versions that lack the pan filter. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] "instead of complaining, submit a patch" [was: Re: minterpolate problem]
Chris Angelico (12021-02-02): > And Phil learned basic courtesy. You mistake the absence of profanity with courtesy. It is a common mistake. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Next Release
Carl Zwanzig (12021-01-26): > What is "invalid" there? linux does point releases, so does freebsd, > firefox, python, bind, glib, clang, etc. Find me a major opensource project, > other than ffmpeg, that tells people to use their development branch. Debian. The number of things based on Sid, or at least testing, is astounding. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Help with creating MP4 video with multiple audio tracks
Chiara via ffmpeg-user (12021-01-18): > I’m new to this, so I apologize if I’m missing something trivial. I > need to create an .mp4 video output with multiple audio tracks in it. > I run the command: > > ffmpeg -i sample-mp4-file.mp4 -i hindi.aac -i tamil.aac -i telugu.aac > -map 1 -map 2 -map 3 -metadata:s:a:0 language=eng -metadata:s:a:1 > language=tam -metadata:s:a:2 language=tel -metadata:s:a:3 language=hin > -codec copy multilanguage.mp4 > > However, the output includes only the multiple audio tracks with no > video (0 kB) You have not mapped the video file. Regards, -- Nicolas George ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
[FFmpeg-user] Discussion on API and infrastructure enhancement projects
Hi. I have started discussions on ffmpeg-devel about possible enhancement for the API and the infrastructure of the project that I have. Since they relate to the public API of the libraries, I would appreciate not only the feedback of other FFmpeg developers, but also the feedback of people who develop with the FFmpeg libraries: please tell us if you think this kind of new APIs would be helpful to you. The discussions are: - Global introduction https://ffmpeg.org/pipermail/ffmpeg-devel/2020-December/274167.html - Global state into structure https://ffmpeg.org/pipermail/ffmpeg-devel/2020-December/274168.html - Unified string / stream API https://ffmpeg.org/pipermail/ffmpeg-devel/2020-December/274169.html - Type descriptors https://ffmpeg.org/pipermail/ffmpeg-devel/2020-December/274170.html - Internal error messages https://ffmpeg.org/pipermail/ffmpeg-devel/2020-December/274171.html - Event loop https://ffmpeg.org/pipermail/ffmpeg-devel/2020-December/274172.html Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Public FFmpeg Docker images built with GitHub Actions
Hi. Ryan Williams (12020-12-06): > Just wanted to mention this in case it's helpful to anyone: > https://hub.docker.com/r/runsascoded/ffmpeg > > These are Docker images I've built and published (from source releases as > well as a few misc Git commits) using GitHub Actions on a fork of the > GitHub FFmpeg mirror: https://github.com/runsascoded/FFmpeg#readme These image, some of them at least, seem to be built with the --enable-nonfree flag. The meaning of this flag is precisely that you are not allowed to redistribute the resulting binaries. Therefore, you already are in break of FFmpeg's license;, you need to delete immediately any binary image built with the --enable-nonfree. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Uninstalling ffmpeg
Bouke (12020-12-02): > So, I get flamed for top posting now, but I will NOT get banned. > That’s a good thing. You may not get explicitly banned, but they may get ignored by the people who could have best answered their question. Personally, I warn once, "please remember that top-posting is forbidden on this list; if you don't know what it means look it up"; if they won't or can't do it, I decide they're not worth my time. One of the problems of this mailing list is that the rudest persons frequently get the most help, under the false hope that helping them will teach them to be less rude. It won't. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Stream specifier ':a' in filtergraph Error
andrei ka (12020-11-11): > ffmpeg would be enuf, ffmpeg would list all the tracks in input files > before starting transco, on failure dude should just check his first > 20lines of log to see if mp4 have snd tracks... Bad advice. The log output of ffmpeg is not meant to be parsed by an application. The fact that it goes to stderr should be a hint. In particular, there are no promises that the syntax of the list of streams will be kept constant. ffprobe is the right tool for this, because the output is guaranteed to be stable. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Cannot find a matching stream for unlabeled input pad 7 on filter Parsed_concat_2
Randy Johnson via ffmpeg-user (12020-10-29): > Sorry Nicolas, but I think I am still confused. I changed it to 16 and > get the same error so I am thinking I am not understanding. 16×(1+1) is still not equal to 4. Please make a little effort, this is middle-school-level math at best. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Cannot find a matching stream for unlabeled input pad 7 on filter Parsed_concat_2
Randy Johnson via ffmpeg-user (12020-10-29): > [0:v]setsar=1[v0];[2:v]setsar=1[v1];[v0][4:a][v1][4:a]concat=n=8:v=1:a=1" 12 34 Still 4 inputs. Now, 8×(1+1) = 16. Sixteen is still not equal to four. Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] Cannot find a matching stream for unlabeled input pad 7 on filter Parsed_concat_2
Randy Johnson via ffmpeg-user (12020-10-29): > "[0:v]setsar=1[v0];[2:v]setsar=1[v1]; > [v0] 1 > [4:a] 2 > [v1] 3 > [4:a] 4 > concat=n=4:v=1:a=1" 4×(1+1) = 8 ≠4 Regards, -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] sudo: ffmpeg: command not found
Marc Erickson (12020-10-28): > I compiled ffmpeg using the instructions here: > > https://trac.ffmpeg.org/wiki/CompilationGuide/Ubuntu > sudo: ffmpeg: command not found You typed "sudo ffmpeg", which is not in this compilation guide, and which you should not have typed. -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
