2

I have a process like this:

  1. i have N input video; I cut & transcode them using the following code:

    ffmpeg.exe -c:v h264_cuvid -resize 1920x1080 -noaccurate_seek -ss 00:00:04.000 -to 00:00:44.240 -i "input_N.MP4" -v error -filter:v fps=fps=25 -c:v h264_nvenc -preset medium -profile high -b:v 8000k -bufsize 8000k -maxrate 10000k -qmin 0 -g 250 -bf 2 -i_qfactor 0.75 -b_qfactor 1.1 "output_N.mp4"

  2. I create a videoArrayFile.txt in the following format:

    file 'myFilePath\output_N.mp4' file 'myFilePath\output_N.mp4' file 'myFilePath\output_N.mp4' ...

  3. I concat the files in videoArrayFile.txt using the following command:

    ffmpeg.exe -f concat -v error -safe 0 -i "myPath\videoArrayFile.txt" -filter:a "volume=1" -c:v copy -c:a aac "myPath\outputConcat.mp4"

This is the ffmpeg log when I run the above command:

[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (50) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (50) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (50) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (50) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (50) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (50) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (50) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input
[aac @ 000001fa4273e000] Number of scalefactor bands in group (51) exceeds limit (49).
Error while decoding stream #0:1: Invalid data found when processing input

The procedure is working but, using some input files, I'm facing some FPS & audio pitch problem: the output file is variable frame rate and the audio speed is wrong.

Ffprobe on the the "output_N" produce the following:

file 'D:\SharedExp_SSD\Outs\0.51.8\2020-10-30_11-45_LancioTandem-30FPS_1604054749\video_HL\tmp\introEncoded.mp4'

Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'introEncoded.mp4':   Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf58.42.100   Duration: 00:00:04.60, start: 0.000000, bitrate: 2707 kb/s
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], 2575 kb/s, 25 fps, 25 tbr, 12800 tbn, 50 tbc (default)
    Metadata:
      handler_name    : Core Media Video
    Stream #0:1(ita): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 131 kb/s (default)
    Metadata:
      handler_name    : Core Media Audio
       file 'D:\SharedExp_SSD\Outs\0.51.8\2020-10-30_11-45_LancioTandem-30FPS_1604054749\video_HL\tmp\Exp_1488_clip_0.mp4'

Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'Exp_1488_clip_0.mp4':   Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf58.42.100   Duration: 00:00:40.27, start: 0.000000, bitrate: 8142 kb/s
    Stream #0:0(eng): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], 8221 kb/s, 25 fps, 25 tbr, 12800 tbn, 50 tbc (default)
    Metadata:
      handler_name    :  GoPro AVC
      timecode        : 12:52:03:24
    Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 32000 Hz, mono, fltp, 69 kb/s (default)
    Metadata:
      handler_name    :  GoPro AAC
    Stream #0:2(eng): Data: none (tmcd / 0x64636D74)
    Metadata:
      handler_name    :  GoPro AVC
      timecode        : 12:52:03:24 Unsupported codec with id 0 for input stream 2

file 'D:\SharedExp_SSD\Outs\0.51.8\2020-10-30_11-45_LancioTandem-30FPS_1604054749\video_HL\tmp\Exp_1488_clip_1.mp4'

Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'Exp_1488_clip_1.mp4':   Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf58.42.100   Duration: 00:00:05.03, start: 0.000000, bitrate: 8460 kb/s
    Stream #0:0(eng): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], 10239 kb/s, 25 fps, 25 tbr, 12800 tbn, 50 tbc (default)
    Metadata:
      handler_name    :  GoPro AVC
      timecode        : 13:22:01:01
    Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 32000 Hz, mono, fltp, 69 kb/s (default)
    Metadata:
      handler_name    :  GoPro AAC
    Stream #0:2(eng): Data: none (tmcd / 0x64636D74), 0 kb/s
    Metadata:
      handler_name    :  GoPro AVC
      timecode        : 13:22:01:01 Unsupported codec with id 0 for input stream 2


file 'D:\SharedExp_SSD\Outs\0.51.8\2020-10-30_11-45_LancioTandem-30FPS_1604054749\video_HL\tmp\Exp_1488_clip_2.mp4'

Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'Exp_1488_clip_2.mp4':   Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf58.42.100   Duration: 00:00:08.03, start: 0.000000, bitrate: 8926 kb/s
    Stream #0:0(eng): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], 9303 kb/s, 25 fps, 25 tbr, 12800 tbn, 50 tbc (default)
    Metadata:
      handler_name    :  GoPro AVC
      timecode        : 13:22:01:01
    Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 32000 Hz, mono, fltp, 69 kb/s (default)
    Metadata:
      handler_name    :  GoPro AAC
    Stream #0:2(eng): Data: none (tmcd / 0x64636D74), 0 kb/s
    Metadata:
      handler_name    :  GoPro AVC
      timecode        : 13:22:01:01 Unsupported codec with id 0 for input stream 2

While ffprobe on outputConcat.mp4 produce

outputConcat.mp4:
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'outputConcat.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf58.42.100
  Duration: 00:00:57.54, start: 0.000000, bitrate: 7900 kb/s
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], 7820 kb/s, 24.28 fps, 25 tbr, 15360 tbn, 50 tbc (default)
    Metadata:
      handler_name    : Core Media Video
    Stream #0:1(ita): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 111 kb/s (default)
    Metadata:
      handler_name    : Core Media Audio

The timebase in outputConcat.mp4 change from the others: is this behaviour related to the different different sample rate of the audio streams( the only difference I can notice in input files)?

As you can see from point 1) the input FPS is set to 25 and all the input video have exactly the same codec and resolution.

How can I concatenate the videos so that the output one have the same FPS of the inputs and no audio pitch problem? Can it be the timebase problem?

Thx, Marco

Improve this question
3
  • Some of the inputs listed in videoArrayFile.txt must not have the same attributes. Show the compelte output of ffmpeg -n -i output_0.mp4 -i output_1.mp4 -i output_2.mp4, etc.
    – llogan
    Nov 3, 2020 at 19:06
  • @llogan I updated the question with new data
    – Marco Soave
    Nov 4, 2020 at 9:17
  • How do you know it is VFR?
    – llogan
    Nov 4, 2020 at 19:06

1 Answer 1

Reset to default
1

I found a partial solution to the problem: the problem was that the audio sample rate of the inputs is not coherent and I was not managing this during the first conversion. Adding -ar 32000 to all the initial conversion string I solved the audio pitch problem. I'm still tring to understand why the fps change

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