How to get the .wav pcm_s16 from this mp4?

[marcorocchini]

Hi,

please respect for cats thanks

However I have this source that you can download

https://www.dropbox.com/s/193tnwcn9nd6yl8/examplePrem.MP4?dl=0

is a MP4 file with avc1 inside and two audio tracks.

Please load it adobe premiere and place the clip in timeline

Next: if I do

ffmpeg.exe -y -i exampleprem.mp4 -vn -acodec pcm_s16le -ar 48000 outffmpeg.wav

considering only the first audio track, place the .wav audio track below the mp4

but


[Attachment 66708 - Click to enlarge]

I get the outputted .wav (the green track) file that in premiere is 1 frame too long when compared to the original .mp4

I wonder: is there a way (possibly with ffmpeg or in commandline) to an audio .wav file (pcm_s16le) of exactly the same lenght of the original when the 2 clip are imported in adobe premiere, and get the audio sync? thanks


ps: I need to automate in batch processing

[smrpix]

Having tried every trick I can think of, I cannot reproduce your error. It keeps behaving correctly. No duration mismatch

But rather than fool around with a CLI, why not just load your files into Adobe Media Encoder and batch export your wav files that way? Then you are assured the files are being interpreted the same way Premiere interprets them.

[october262]

Hi,

please respect for cats thanks

However I have this source that you can download

https://www.dropbox.com/s/193tnwcn9nd6yl8/examplePrem.MP4?dl=0

is a MP4 file with avc1 inside and two audio tracks.

Please load it adobe premiere and place the clip in timeline

Next: if I do

ffmpeg.exe -y -i exampleprem.mp4 -vn -acodec pcm_s16le -ar 48000 outffmpeg.wav

considering only the first audio track, place the .wav audio track below the mp4

but


[Attachment 66708 - Click to enlarge]

I get the outputted .wav (the green track) file that in premiere is 1 frame too long when compared to the original .mp4

I wonder: is there a way (possibly with ffmpeg or in commandline) to an audio .wav file (pcm_s16le) of exactly the same lenght of the original when the 2 clip are imported in adobe premiere, and get the audio sync? thanks


ps: I need to automate in batch processing

try this here - https://lzone.de/blog/Easily-fix-async-video-with-ffmpeg

[ProWo]

Your examplePrem.MP4 contains two ac3 audiostreams, no pcm stream there.


[Attachment 66714 - Click to enlarge]

[marcorocchini]

In attachement the outffmpeg.wav get with ffmpeg using this commandline on the original source examplePrem.MP4

ffmpeg.exe -y -i exampleprem.mp4 -vn -acodec pcm_s16le -ar 48000 outffmpeg.wav

I place the clip examplePrem.MP4 in the adobe premiere timeline

and below the .wav track outffmpeg.wav (the green track in the image)

but the .wav seems too long of 2 frames


[Attachment 66716 - Click to enlarge]

So I wonder if is there a way to batch calculate the duration of the original and tells to ffmpeg that have to generate a .wav cutted with the lenght that match exactly the original, the target is to have a .wav that have the same lenght when placed in timeline

[ProWo]

ac3 and wav have exactly the same length.
The error is therefore due to the Adobe Premiere display.


[Attachment 66717 - Click to enlarge]

[jagabo]

Yes, the video has 182 frames at 25 fps. That makes the length 7.280 seconds. So the real question is why is the video only 7.0 seconds long in Premiere?

[marcorocchini]

ac3 and wav have exactly the same length.
The error is therefore due to the Adobe Premiere display.


[Attachment 66717 - Click to enlarge]

[Attachment 66720 - Click to enlarge]

mmmmm

[marcorocchini]

@Echo Off 

        ffmpeg64bitAug2019.exe -loglevel quiet -y -i exampleprem.mp4 -map 0:a:0 -vn -acodec pcm_s16le -ar 48000 outffmpeg.wav

        if exist InputDuration.txt del InputDuration.txt
        FFProbe64bit2014.exe -loglevel fatal -show_entries format=duration -of csv="p=0" -sexagesimal exampleprem.mp4>InputDuration.txt
        set /p InputDuration=<InputDuration.txt
        echo InputDuration is %InputDuration%


        if exist wavFFmpegDuration.txt del wavFFmpegDuration.txt
        FFProbe64bit2014.exe -loglevel fatal -show_entries format=duration -of csv="p=0" -sexagesimal outffmpeg.wav>wavFFmpegDuration.txt
        set /p wavFFmpegDuration=<wavFFmpegDuration.txt
        echo wavFFmpegDuration is %wavFFmpegDuration%


        if exist InputDuration.txt del InputDuration.txt
echo.
        if exist wavFFmpegDuration.txt del wavFFmpegDuration.txt


pause

InputDuration is 0:00:07.291000
wavFFmpegDuration is 0:00:07.290667

oh my ***

however ffprobe's duration is not exactly the same. So I wonder, is there a way - in batch - to do so that both the files in premiere have the same lenght?

[ProWo]

InputDuration is 0:00:07.291000
wavFFmpegDuration is 0:00:07.290667

Do you think really to note a 0.333 ms (milliseconds) difference?