Opened 8 years ago

Closed 8 years ago

#5120 closed defect (fixed)

Incorrect start frame when converting mpeg2video in .mov to mp4

Reported by: sroy8 Owned by:
Priority: normal Component: avformat
Version: git-master Keywords: mov edts
Cc: Blocked By:
Blocking: Reproduced by developer: no
Analyzed by developer: no

Description

Summary of the bug:

When I convert an mpeg2video in a .mov container to mp4, the output includes additional frames that are before the start frame in the input. This is possible because the start time of the input is non-zero.

To reproduce:

% ffmpeg -i incorrect-start-frame.mov incorrect-start-frame.mp4

You can download incorrect-start-frame.mov at http://www.datafilehost.com/d/6edc3c9b, and a -report log from running this command with ffmpeg 2.8.4 at http://www.datafilehost.com/d/3575bc05.

In more detail, ffprobe on the input gives the following duration and start:

Duration: 00:00:00.70, start: 0.522533, bitrate: 46718 kb/s

In contrast, ffprobe on the output gives:

Duration: 00:00:01.24, start: 0.021313, bitrate: 10801 kb/s

I would be fine with small discrepancies. However, the beginning of the output includes frames that are before the start of the input, which is a problem. I end up with these input files when I capture video from a Canon HV20 camera using iMovie. iMovie splits the video into scenes, and it's common for a file to include a few additional frames from the previous scene before the video start time. The input video suppresses these frames by setting the start time. However, the output video incorrectly shows them. Often, these frames have no relationship to the rest of the video.

My workaround has been to use gawk to extract the start time of the input video and then pass this to ffmpeg using -ss. For example:

% ffmpeg -ss 0.522533 -i incorrect-start-frame.mov correct-start-frame.mp4

I've tried many different flags to try to get the right behavior without needing -ss, without success. However, even if there is a correct flag setting, it seems like a bug from a user standpoint that the default behavior includes the extra frames.

Change History (10)

comment:1 by Carl Eugen Hoyos, 8 years ago

Keywords: mov added

Please test current FFmpeg git head and please provide the command line that allows to reproduce the issue together with the complete, uncut console output here on the bug tracker to make this a valid ticket.

comment:2 by sroy8, 8 years ago

I've confirmed that the bug still exists at git head. Here is the output from running ffmpeg on incorrect-start-frame.mov:

% ffmpeg -report -i incorrect-start-frame.mov incorrect-start-frame.mp4
ffmpeg started on 2016-01-03 at 12:35:04
Report written to "ffmpeg-20160103-123504.log"
ffmpeg version N-77671-g97c162a Copyright (c) 2000-2016 the FFmpeg developers
  built with Apple LLVM version 7.0.2 (clang-700.1.81)
  configuration: 
  libavutil      55. 12.100 / 55. 12.100
  libavcodec     57. 21.100 / 57. 21.100
  libavformat    57. 21.100 / 57. 21.100
  libavdevice    57.  0.100 / 57.  0.100
  libavfilter     6. 23.100 /  6. 23.100
  libswscale      4.  0.100 /  4.  0.100
  libswresample   2.  0.101 /  2.  0.101
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x7fafe2802000] ignoring 'frma' atom of 'fl32', stream format is 'fl32'
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'incorrect-start-frame.mov':
  Metadata:
    major_brand     : qt  
    minor_version   : 0
    compatible_brands: qt  
    creation_time   : 2016-01-01 21:40:51
    com.apple.proapps.manufacturer: Canon
    com.apple.proapps.modelname: HV20
    com.apple.proapps.cameraID:   0x8500014e7616
    com.apple.proapps.cameraName: Canon HV20
    com.apple.proapps.clipID: 013DBAE2-5BEA-411E-8CB7-6CE523785DDA
    com.apple.proapps.ingestDate.description: 2016-01-01 13:40:51 -0800
    com.apple.proapps.originalFormat: HDV 1080i60
    com.apple.proapps.mediaRate: @>
    com.apple.proapps.timecodeFormat: Drop
    com.apple.quicktime.creationdate: 2015-12-28T18:01:18-0800
    com.apple.quicktime.make: Apple
    com.apple.quicktime.model: MacBookPro8,2
    com.apple.quicktime.software: Mac OS X 10.11.2 (15C50)
  Duration: 00:00:00.70, start: 0.522533, bitrate: 46718 kb/s
    Stream #0:0(und): Video: mpeg2video (Main) (hdv2 / 0x32766468), yuv420p(tv, bt709), 1440x1080 [SAR 4:3 DAR 16:9], 25000 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc (default)
    Metadata:
      creation_time   : 2016-01-01 21:40:51
      handler_name    : Core Media Data Handler
      encoder         : HDV 1080i60
      timecode        : 00:50:34;09
    Stream #0:1(und): Audio: pcm_f32le (fl32 / 0x32336C66), 48000 Hz, stereo, flt, 3072 kb/s (default)
    Metadata:
      creation_time   : 2016-01-01 21:40:51
      handler_name    : Core Media Data Handler
    Stream #0:2(und): Data: none (tmcd / 0x64636D74), 0 kb/s
    Metadata:
      creation_time   : 2016-01-01 21:40:51
      handler_name    : Core Media Data Handler
      timecode        : 00:50:34;09
Output #0, mp4, to 'incorrect-start-frame.mp4':
  Metadata:
    major_brand     : qt  
    minor_version   : 0
    compatible_brands: qt  
    com.apple.quicktime.software: Mac OS X 10.11.2 (15C50)
    com.apple.proapps.manufacturer: Canon
    com.apple.proapps.modelname: HV20
    com.apple.proapps.cameraID:   0x8500014e7616
    com.apple.proapps.cameraName: Canon HV20
    com.apple.proapps.clipID: 013DBAE2-5BEA-411E-8CB7-6CE523785DDA
    com.apple.proapps.ingestDate.description: 2016-01-01 13:40:51 -0800
    com.apple.proapps.originalFormat: HDV 1080i60
    com.apple.proapps.mediaRate: @>
    com.apple.proapps.timecodeFormat: Drop
    com.apple.quicktime.creationdate: 2015-12-28T18:01:18-0800
    com.apple.quicktime.make: Apple
    com.apple.quicktime.model: MacBookPro8,2
    encoder         : Lavf57.21.100
    Stream #0:0(und): Video: mpeg4 ( [0][0][0] / 0x0020), yuv420p, 1440x1080 [SAR 4:3 DAR 16:9], q=2-31, 200 kb/s, 29.97 fps, 30k tbn, 29.97 tbc (default)
    Metadata:
      creation_time   : 2016-01-01 21:40:51
      handler_name    : Core Media Data Handler
      timecode        : 00:50:34;09
      encoder         : Lavc57.21.100 mpeg4
    Side data:
      unknown side data type 10 (24 bytes)
    Stream #0:1(und): Audio: aac (LC) ([64][0][0][0] / 0x0040), 48000 Hz, stereo, fltp, 128 kb/s (default)
    Metadata:
      creation_time   : 2016-01-01 21:40:51
      handler_name    : Core Media Data Handler
      encoder         : Lavc57.21.100 aac
Stream mapping:
  Stream #0:0 -> #0:0 (mpeg2video (native) -> mpeg4 (native))
  Stream #0:1 -> #0:1 (pcm_f32le (native) -> aac (native))
Press [q] to stop, [?] for help
frame=   37 fps=0.0 q=24.8 Lsize=    1081kB time=00:00:01.23 bitrate=7170.2kbits/s dup=5 drop=0 speed=3.09x    
video:1061kB audio:17kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.214646%
[aac @ 0x7fafe1813c00] Qavg: 193.488

Here is the corresponding report file:

% cat ffmpeg-20160103-123504.log
ffmpeg started on 2016-01-03 at 12:35:04
Report written to "ffmpeg-20160103-123504.log"
Command line:
./ffmpeg -report -i incorrect-start-frame.mov incorrect-start-frame.mp4
ffmpeg version N-77671-g97c162a Copyright (c) 2000-2016 the FFmpeg developers
  built with Apple LLVM version 7.0.2 (clang-700.1.81)
  configuration: 
  libavutil      55. 12.100 / 55. 12.100
  libavcodec     57. 21.100 / 57. 21.100
  libavformat    57. 21.100 / 57. 21.100
  libavdevice    57.  0.100 / 57.  0.100
  libavfilter     6. 23.100 /  6. 23.100
  libswscale      4.  0.100 /  4.  0.100
  libswresample   2.  0.101 /  2.  0.101
Splitting the commandline.
Reading option '-report' ... matched as option 'report' (generate a report) with argument '1'.
Reading option '-i' ... matched as input file with argument 'incorrect-start-frame.mov'.
Reading option 'incorrect-start-frame.mp4' ... matched as output file.
Finished splitting the commandline.
Parsing a group of options: global .
Applying option report (generate a report) with argument 1.
Successfully parsed a group of options.
Parsing a group of options: input file incorrect-start-frame.mov.
Successfully parsed a group of options.
Opening an input file: incorrect-start-frame.mov.
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x7fafe2802000] Format mov,mp4,m4a,3gp,3g2,mj2 probed with size=2048 and score=100
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x7fafe2802000] ISO: File Type Major Brand: qt  
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x7fafe2802000] Unknown dref type 0x0873696c61 size 12
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x7fafe2802000] Unknown dref type 0x0873696c61 size 12
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x7fafe2802000] ignoring 'frma' atom of 'fl32', stream format is 'fl32'
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x7fafe2802000] Unknown dref type 0x0873696c61 size 12
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x7fafe2802000] Before avformat_find_stream_info() pos: 4091925 bytes read:43050 seeks:1
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x7fafe2802000] All info found
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x7fafe2802000] After avformat_find_stream_info() pos: 1556480 bytes read:1619501 seeks:2 frames:16
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'incorrect-start-frame.mov':
  Metadata:
    major_brand     : qt  
    minor_version   : 0
    compatible_brands: qt  
    creation_time   : 2016-01-01 21:40:51
    com.apple.proapps.manufacturer: Canon
    com.apple.proapps.modelname: HV20
    com.apple.proapps.cameraID:   0x8500014e7616
    com.apple.proapps.cameraName: Canon HV20
    com.apple.proapps.clipID: 013DBAE2-5BEA-411E-8CB7-6CE523785DDA
    com.apple.proapps.ingestDate.description: 2016-01-01 13:40:51 -0800
    com.apple.proapps.originalFormat: HDV 1080i60
    com.apple.proapps.mediaRate: @>
    com.apple.proapps.timecodeFormat: Drop
    com.apple.quicktime.creationdate: 2015-12-28T18:01:18-0800
    com.apple.quicktime.make: Apple
    com.apple.quicktime.model: MacBookPro8,2
    com.apple.quicktime.software: Mac OS X 10.11.2 (15C50)
  Duration: 00:00:00.70, start: 0.522533, bitrate: 46718 kb/s
    Stream #0:0(und), 15, 1/30000: Video: mpeg2video (Main) (hdv2 / 0x32766468), yuv420p(tv, bt709), 1440x1080 [SAR 4:3 DAR 16:9], 25000 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc (default)
    Metadata:
      creation_time   : 2016-01-01 21:40:51
      handler_name    : Core Media Data Handler
      encoder         : HDV 1080i60
      timecode        : 00:50:34;09
    Stream #0:1(und), 1, 1/48000: Audio: pcm_f32le (fl32 / 0x32336C66), 48000 Hz, stereo, flt, 3072 kb/s (default)
    Metadata:
      creation_time   : 2016-01-01 21:40:51
      handler_name    : Core Media Data Handler
    Stream #0:2(und), 0, 1/30000: Data: none (tmcd / 0x64636D74), 0 kb/s
    Metadata:
      creation_time   : 2016-01-01 21:40:51
      handler_name    : Core Media Data Handler
      timecode        : 00:50:34;09
Successfully opened the file.
Parsing a group of options: output file incorrect-start-frame.mp4.
Successfully parsed a group of options.
Opening an output file: incorrect-start-frame.mp4.
Successfully opened the file.
detected 8 logical cores
[graph 0 input from stream 0:0 @ 0x7fafe140cf00] Setting 'video_size' to value '1440x1080'
[graph 0 input from stream 0:0 @ 0x7fafe140cf00] Setting 'pix_fmt' to value '0'
[graph 0 input from stream 0:0 @ 0x7fafe140cf00] Setting 'time_base' to value '1/30000'
[graph 0 input from stream 0:0 @ 0x7fafe140cf00] Setting 'pixel_aspect' to value '4/3'
[graph 0 input from stream 0:0 @ 0x7fafe140cf00] Setting 'sws_param' to value 'flags=2'
[graph 0 input from stream 0:0 @ 0x7fafe140cf00] Setting 'frame_rate' to value '30000/1001'
[graph 0 input from stream 0:0 @ 0x7fafe140cf00] w:1440 h:1080 pixfmt:yuv420p tb:1/30000 fr:30000/1001 sar:4/3 sws_param:flags=2
[format @ 0x7fafe140d4e0] compat: called with args=[yuv420p]
[format @ 0x7fafe140d4e0] Setting 'pix_fmts' to value 'yuv420p'
[AVFilterGraph @ 0x7fafe140c9a0] query_formats: 4 queried, 3 merged, 0 already done, 0 delayed
[graph 1 input from stream 0:1 @ 0x7fafe1700100] Setting 'time_base' to value '1/48000'
[graph 1 input from stream 0:1 @ 0x7fafe1700100] Setting 'sample_rate' to value '48000'
[graph 1 input from stream 0:1 @ 0x7fafe1700100] Setting 'sample_fmt' to value 'flt'
[graph 1 input from stream 0:1 @ 0x7fafe1700100] Setting 'channel_layout' to value '0x3'
[graph 1 input from stream 0:1 @ 0x7fafe1700100] tb:1/48000 samplefmt:flt samplerate:48000 chlayout:0x3
[audio format for output stream 0:1 @ 0x7fafe17009a0] Setting 'sample_fmts' to value 'fltp'
[audio format for output stream 0:1 @ 0x7fafe17009a0] Setting 'sample_rates' to value '96000|88200|64000|48000|44100|32000|24000|22050|16000|12000|11025|8000|7350'
[audio format for output stream 0:1 @ 0x7fafe17009a0] auto-inserting filter 'auto-inserted resampler 0' between the filter 'Parsed_anull_0' and the filter 'audio format for output stream 0:1'
[AVFilterGraph @ 0x7fafe140d980] query_formats: 4 queried, 6 merged, 3 already done, 0 delayed
[auto-inserted resampler 0 @ 0x7fafe1701220] [SWR @ 0x7fafe401b200] Using fltp internally between filters
[auto-inserted resampler 0 @ 0x7fafe1701220] ch:2 chl:stereo fmt:flt r:48000Hz -> ch:2 chl:stereo fmt:fltp r:48000Hz
[mpeg4 @ 0x7fafe18a4a00] intra_quant_bias = 0 inter_quant_bias = -64
Output #0, mp4, to 'incorrect-start-frame.mp4':
  Metadata:
    major_brand     : qt  
    minor_version   : 0
    compatible_brands: qt  
    com.apple.quicktime.software: Mac OS X 10.11.2 (15C50)
    com.apple.proapps.manufacturer: Canon
    com.apple.proapps.modelname: HV20
    com.apple.proapps.cameraID:   0x8500014e7616
    com.apple.proapps.cameraName: Canon HV20
    com.apple.proapps.clipID: 013DBAE2-5BEA-411E-8CB7-6CE523785DDA
    com.apple.proapps.ingestDate.description: 2016-01-01 13:40:51 -0800
    com.apple.proapps.originalFormat: HDV 1080i60
    com.apple.proapps.mediaRate: @>
    com.apple.proapps.timecodeFormat: Drop
    com.apple.quicktime.creationdate: 2015-12-28T18:01:18-0800
    com.apple.quicktime.make: Apple
    com.apple.quicktime.model: MacBookPro8,2
    encoder         : Lavf57.21.100
    Stream #0:0(und), 0, 1/30000: Video: mpeg4 ( [0][0][0] / 0x0020), yuv420p, 1440x1080 [SAR 4:3 DAR 16:9], q=2-31, 200 kb/s, 29.97 fps, 30k tbn, 29.97 tbc (default)
    Metadata:
      creation_time   : 2016-01-01 21:40:51
      handler_name    : Core Media Data Handler
      timecode        : 00:50:34;09
      encoder         : Lavc57.21.100 mpeg4
    Side data:
      unknown side data type 10 (24 bytes)
    Stream #0:1(und), 0, 1/48000: Audio: aac (LC) ([64][0][0][0] / 0x0040), 48000 Hz, stereo, fltp, 128 kb/s (default)
    Metadata:
      creation_time   : 2016-01-01 21:40:51
      handler_name    : Core Media Data Handler
      encoder         : Lavc57.21.100 aac
Stream mapping:
  Stream #0:0 -> #0:0 (mpeg2video (native) -> mpeg4 (native))
  Stream #0:1 -> #0:1 (pcm_f32le (native) -> aac (native))
Press [q] to stop, [?] for help
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
*** 3 dup!
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
Clipping frame in rate conversion by 0.339653
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
Clipping frame in rate conversion by 0.339653
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
Clipping frame in rate conversion by 0.339653
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
Clipping frame in rate conversion by 0.339653
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
Clipping frame in rate conversion by 0.339653
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
Clipping frame in rate conversion by 0.339653
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
Clipping frame in rate conversion by 0.339653
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
Clipping frame in rate conversion by 0.339653
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
Clipping frame in rate conversion by 0.339653
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
Clipping frame in rate conversion by 0.339653
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
Clipping frame in rate conversion by 0.339653
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
Clipping frame in rate conversion by 0.339653
Clipping frame in rate conversion by 0.339653
Clipping frame in rate conversion by 0.339653
Clipping frame in rate conversion by 0.339653
Clipping frame in rate conversion by 0.339653
Clipping frame in rate conversion by 0.339653
Clipping frame in rate conversion by 0.339653
Clipping frame in rate conversion by 0.339653
Clipping frame in rate conversion by 0.339653
Clipping frame in rate conversion by 0.339653
Clipping frame in rate conversion by 0.339653
Clipping frame in rate conversion by 0.339653
Clipping frame in rate conversion by 0.339653
Clipping frame in rate conversion by 0.339653
Clipping frame in rate conversion by 0.339653
Clipping frame in rate conversion by 0.339653
Clipping frame in rate conversion by 0.339653
Clipping frame in rate conversion by 0.339653
Clipping frame in rate conversion by 0.339653
*** 2 dup!
[output stream 0:1 @ 0x7fafe1700480] EOF on sink link output stream 0:1:default.
[output stream 0:0 @ 0x7fafe140d220] EOF on sink link output stream 0:0:default.
No more output streams to write to, finishing.
[aac @ 0x7fafe1813c00] Trying to remove 128 more samples than there are in the queue
frame=   37 fps=0.0 q=24.8 Lsize=    1081kB time=00:00:01.23 bitrate=7170.2kbits/s dup=5 drop=0 speed=3.09x    
video:1061kB audio:17kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.214646%
Input file #0 (incorrect-start-frame.mov):
  Input stream #0:0 (video): 34 packets read (3636809 bytes); 32 frames decoded; 
  Input stream #0:1 (audio): 54 packets read (433152 bytes); 54 frames decoded (54144 samples); 
  Input stream #0:2 (data): 0 packets read (0 bytes); 
  Total: 88 packets (4069961 bytes) demuxed
Output file #0 (incorrect-start-frame.mp4):
  Output stream #0:0 (video): 37 frames encoded; 37 packets muxed (1086294 bytes); 
  Output stream #0:1 (audio): 53 frames encoded (54144 samples); 54 packets muxed (17850 bytes); 
  Total: 91 packets (1104144 bytes) muxed
86 frames successfully decoded, 0 decoding errors
[AVIOContext @ 0x7fafe140c5a0] Statistics: 60 seeks, 154 writeouts
[aac @ 0x7fafe1813c00] Qavg: 193.488
[AVIOContext @ 0x7fafe1600560] Statistics: 4130879 bytes read, 2 seeks

Here is the relevant duration and start from the input incorrect-start-frame.mov:

% ffprobe incorrect-start-frame.mov 2>&1 | grep Duration
  Duration: 00:00:00.70, start: 0.522533, bitrate: 46718 kb/s

And here is the relevant duration and start from the output incorrect-start-frame.mp4:

% ffprobe incorrect-start-frame.mp4 2>&1 | grep Duration
  Duration: 00:00:01.24, start: 0.021313, bitrate: 7167 kb/s

Aside from the duration mismatch, the problem with the incorrect start frame is easy to see when viewing the input and output files.

comment:3 by sroy8, 8 years ago

Summary: Incorrect start frame when converting mpeg2video to mp4Incorrect start frame when converting mpeg2video in .mov to mp4

comment:4 by Carl Eugen Hoyos, 8 years ago

I still don't understand your issue:
The input file you uploaded is 1.2 seconds long. Do you expect that the output file by default only has a duration of 0.7?

comment:5 by sroy8, 8 years ago

No, it would be fine for the output to have a duration of 1.2 seconds as long as the start time is around 0.5. Then the output would show the same frames as the input and be the same length. As it stands, if you play the two videos the output is both longer than the input, presumably by 0.5s, and it shows extra frames at the beginning that do not show up in the input. Do you not see this effect?

I'm playing the videos using Quicktime Player on a Mac. Do other video players show something different, not respecting the start time of the video?

comment:6 by Carl Eugen Hoyos, 8 years ago

Are you saying that the input video plays less than a second with QuickTime?

comment:7 by sroy8, 8 years ago

Yes, iMovie shows the time of the input file as 0.7s, and the time of the output file as 1.2s. This corresponds to what I see in Quicktime, though Quicktime doesn't display times at sub-second precision, so I can't confirm there. I can confirm that in iMovie the two files look very different.

The output I'm expecting is roughly the equivalent of:

% ffmpeg -ss 0.522533 -i incorrect-start-frame.mov correct-start-frame.mp4

This uses -ss with the start time value of the input video. Running ffprobe on correct-start-frame.mp4 gives:

% ffprobe correct-s
  Duration: 00:00:00.70, start: 0.021333, bitrate: 11945 kb/s

Inspecting this by eye, the result still isn't quite right, since the initial frame looks slightly different. You can see that the feet are cut off at the bottom of the picture in a slightly different position than in the input video.

comment:8 by Carl Eugen Hoyos, 8 years ago

Note that the input file seems to be vfr, this is not supported by the mov muxer, so you always get a different amount of frames in the output file.

comment:9 by sroy8, 8 years ago

That's fine, it's not important that the number of frames is the same. However, from a user standpoint it's clearly a bug to show content in the output that's not visible in the input.

comment:10 by Carl Eugen Hoyos, 8 years ago

Component: undeterminedavformat
Keywords: edts added
Resolution: fixed
Status: newclosed
Version: unspecifiedgit-master
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