One frame lost when converting 25fps to 50fps

[Robert Krüger]

Hi,

I have come across this regardless of video format:

ffmbc -i ~/tmp/samples/software/fcp_7/prores/fcp7_prores_hq_1080_25p_2s.mov -vcodec prores -an -r 50 50test.mov 

FFmbc version 0.7-rc7

Copyright (c) 2008-2012 Baptiste Coudurier and the FFmpeg developers

Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/Users/krueger/tmp/samples/software/fcp_7/prores/fcp7_prores_hq_1080_25p_2s.mov':

  Metadata:

    major_brand: qt  

    minor_version: 537199360

    compatible_brands: qt  

    creation_time: 2012-05-24 12:42:17

    com.apple.finalcutstudio.media.uuid: AFFD54A5-936C-42FF-AEDA-31AF3F0ACFED

    timecode: 01:00:00:00

  Duration: 00:00:02.00, start: 0.000000, bitrate: 94526 kb/s

    Stream #0.0(eng): Video: prores, yuv422p10le, 1920x1080p, 92946 kb/s, PAR 1:1 DAR 16:9, 25.00 fps

    Metadata:

      codec_name: Apple ProRes 422 (HQ)

    Stream #0.1(eng): Audio: pcm_s16le, 48000 Hz, 2 channels, s16, 1536 kb/s

    Stream #0.2(eng): Data: unknown (tmcd)

Output #0, mov, to '50test.mov':

  Metadata:

    encoder: FFmbc 0.7

    Stream #0.0(und): Video: prores, yuv422p10le, 1920x1080p [PAR 1:1 DAR 16:9], 367001 kb/s, 50.00 fps

Stream mapping:

  Stream #0.0 -> #0.0

Press [q] to stop, [?] for help

frame=   99 fps= 27 q=1.0 Lsize=   43781kB time=00:00:01.98 bitrate=181137.6kbits/s dup=49 drop=0               

video:43779kB audio:0kB global headers:0kB muxing overhead 0.003395%

Roberts-MacBook-Pro:FFmbc-0.7-rc7 krueger$ ./ffmbc -i 50test.mov 

FFmbc version 0.7-rc7

Copyright (c) 2008-2012 Baptiste Coudurier and the FFmpeg developers

Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '50test.mov':

  Metadata:

    major_brand: qt  

    minor_version: 0

    compatible_brands: qt  

    creation_time: 2012-11-05 07:58:25

    encoder: FFmbc 0.7

  Duration: 00:00:01.98, start: 0.000000, bitrate: 181137 kb/s

    Stream #0.0(eng): Video: prores, yuv422p10le, 1920x1080p, 181131 kb/s, 50.00 fps

    Metadata:

      codec_name: prores

At least one output file must be specified

You can see that one frame was lost by looking at the duration and the output. It should read "dup=50" but it's "dup=49", i.e. one  frame of the 50 input frames was not duplicated.

Regards,

Robert

[Baptiste Coudurier]

Hi Robert,

Indeed, I'll fix that

--
Baptiste COUDURIER
Key fingerprint 8D77134D20CC9220201FC5DB0AC9325C5C1ABAAA
FFmpeg maintainer http://www.ffmpeg.org

[Robert Krüger]

HI Baptiste,

Thanks!