[FFmpeg-trac] #4235(ffmpeg:new): Converting GIF to MP4 using FFmpeg produces a video that doesn't follow the GIF frame timings.

[FFmpeg]

#4235: Converting GIF to MP4 using FFmpeg produces a video that doesn't follow the
GIF frame timings.
--------------------------------+----------------------------------
             Reporter:  dvir    |                     Type:  defect
               Status:  new     |                 Priority:  normal
            Component:  ffmpeg  |                  Version:  2.3.5
             Keywords:  gif     |               Blocked By:
             Blocking:          |  Reproduced by developer:  0
Analyzed by developer:  0       |
--------------------------------+----------------------------------
 Summary of the bug:
 Converting GIF to MP4 using FFmpeg produces a video that doesn't follow
 the GIF frame timings.

 I'm using FFmpeg to convert a GIF into an MP4, with the following command:
 {{{ffmpeg -f gif -i ~/transparent.gif  -c:v libx264 -f mp4
 ./transparent.mp4}}}

 This is the input GIF:
 http://media.giphy.com/media/lXiRla43JDySJhTLW/giphy.gif
 This is the the output mp4: https://vid.me/aGv6

 it seems like FFmpeg is skipping the first frame of the GIF, and skips the
 timing for the last frame (the first and last frame are 2000ms long, yet
 it doesn't halt at the end like it does in the beginning).

 The frame timings are: (produced with ImageMagick -- 'identify -format
 '%T|' ~/transparent.gif')
 200|5|5|5|5|10|10|10|10|10|10|10|200

 This means the first frame should be 2000ms long, and so is the last one.
 For the last frame, the timing is messed (doesn't half for 2000ms), and it
 seems to skip the first frame, which doesn't show the metal hand. You
 could look at the input GIF and see that it is different from the product
 MP4.

 How to reproduce:
 Re-run the command described above on the input GIF linked to above.

 Verbose input file information:
 {{{
 % dvir-mbp1:tmp dvir$ ffmpeg -v 9 -loglevel 99 -i ~/transparent.gif
 ffmpeg version 2.3.3 Copyright (c) 2000-2014 the FFmpeg developers
   built on Aug 25 2014 19:47:15 with Apple LLVM version 5.1
 (clang-503.0.40) (based on LLVM 3.4svn)
   configuration: --prefix=/usr/local/Cellar/ffmpeg/2.3.3 --enable-shared
 --enable-pthreads --enable-gpl --enable-version3 --enable-nonfree
 --enable-hardcoded-tables --enable-avresample --enable-vda --cc=clang
 --host-cflags= --host-ldflags= --enable-libx264 --enable-libfaac --enable-
 libmp3lame --enable-libxvid
   libavutil      52. 92.100 / 52. 92.100
   libavcodec     55. 69.100 / 55. 69.100
   libavformat    55. 48.100 / 55. 48.100
   libavdevice    55. 13.102 / 55. 13.102
   libavfilter     4. 11.100 /  4. 11.100
   libavresample   1.  3.  0 /  1.  3.  0
   libswscale      2.  6.100 /  2.  6.100
   libswresample   0. 19.100 /  0. 19.100
   libpostproc    52.  3.100 / 52.  3.100
 Splitting the commandline.
 Reading option '-v' ... matched as option 'v' (set logging level) with
 argument '9'.
 Reading option '-loglevel' ... matched as option 'loglevel' (set logging
 level) with argument '99'.
 Reading option '-i' ... matched as input file with argument
 '/Users/dvir/transparent.gif'.
 Finished splitting the commandline.
 Parsing a group of options: global .
 Applying option v (set logging level) with argument 9.
 Successfully parsed a group of options.
 Parsing a group of options: input file /Users/dvir/transparent.gif.
 Successfully parsed a group of options.
 Opening an input file: /Users/dvir/transparent.gif.
 [gif @ 0x7fa549800000] Format gif probed with size=2048 and score=100
 [gif @ 0x7fa549800000] Before avformat_find_stream_info() pos: 0 bytes
 read:3233 seeks:0
 rfps: 19.583333 0.014962
 rfps: 19.666667 0.009576
     Last message repeated 1 times
 rfps: 19.750000 0.005386
 rfps: 19.833333 0.002394
     Last message repeated 1 times
 rfps: 19.916667 0.000598
     Last message repeated 1 times
 rfps: 20.000000 0.000000
 rfps: 20.083333 0.000598
     Last message repeated 1 times
 rfps: 20.166667 0.002394
     Last message repeated 1 times
 rfps: 20.250000 0.005386
 rfps: 20.333333 0.009576
     Last message repeated 1 times
 rfps: 20.416667 0.014962
 rfps: 39.583333 0.014962
 rfps: 39.666667 0.009576
     Last message repeated 1 times
 rfps: 39.750000 0.005386
 rfps: 39.833333 0.002394
     Last message repeated 1 times
 rfps: 39.916667 0.000598
     Last message repeated 1 times
 rfps: 40.000000 0.000000
 rfps: 40.083333 0.000598
     Last message repeated 1 times
 rfps: 40.166667 0.002394
     Last message repeated 1 times
 rfps: 40.250000 0.005386
 rfps: 40.333333 0.009576
     Last message repeated 1 times
 rfps: 40.416667 0.014962
 rfps: 59.583333 0.014962
 rfps: 59.666667 0.009576
     Last message repeated 1 times
 rfps: 59.750000 0.005386
 rfps: 59.833333 0.002394
     Last message repeated 1 times
 rfps: 59.916667 0.000598
     Last message repeated 1 times
 rfps: 60.000000 0.000000
 rfps: 59.940060 0.000310
     Last message repeated 1 times
 [gif @ 0x7fa549800000] After avformat_find_stream_info() pos: 3233 bytes
 read:3233 seeks:0 frames:13
 Input #0, gif, from '/Users/dvir/transparent.gif':
   Duration: N/A, bitrate: N/A
     Stream #0:0, 13, 1/100: Video: gif, bgra, 50x32, 1/100, 3.83 fps, 20
 tbr, 100 tbn, 100 tbc
 Successfully opened the file.
 At least one output file must be specified
 [AVIOContext @ 0x7fa548e00140] Statistics: 3233 bytes read, 0 seeks
 }}}

--
Ticket URL: <https://trac.ffmpeg.org/ticket/4235>
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