-vsync 0
ffmpeg -i a.mp4 -filter:v select='eq(pict_type\,I)' -vsync 0 I.%06d.png
$ ffmpeg -i a.mp4 -filter:v select='eq(pict_type\,I)' -vsync 0 I.%06d.png
ffmpeg version git-2014-01-14-abcde Copyright (c) 2000-2014 the FFmpeg developers
built on Jan 14 2014 09:10:34 with gcc 4.6 (Ubuntu/Linaro 4.6.3-1ubuntu5)
configuration: <snip>
libavutil 52. 62.100 / 52. 62.100
libavcodec 55. 48.101 / 55. 48.101
libavformat 55. 23.103 / 55. 23.103
libavdevice 55. 5.102 / 55. 5.102
libavfilter 4. 1.100 / 4. 1.100
libswscale 2. 5.101 / 2. 5.101
libswresample 0. 17.104 / 0. 17.104
libpostproc 52. 3.100 / 52. 3.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'a.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
creation_time : 1970-01-01 00:00:00
encoder : Lavf53.29.100
Duration: 00:19:02.63, start: 0.000000, bitrate: 128 kb/s
Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 960x540 [SAR 1:1 DAR 16:9], 43 kb/s, 30 fps, 30 tbr, 30 tbn, 60 tbc (default)
Metadata:
creation_time : 1970-01-01 00:00:00
handler_name : VideoHandler
Stream #0:1(und): Audio: aac (mp4a / 0x6134706D), 44100 Hz, mono, fltp, 75 kb/s (default)
Metadata:
creation_time : 1970-01-01 00:00:00
handler_name : SoundHandler
Output #0, image2, to 'I.%06d.png':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf55.23.103
Stream #0:0(und): Video: png, rgb24, 960x540 [SAR 1:1 DAR 16:9], q=2-31, 200 kb/s, 90k tbn, 30 tbc (default)
Metadata:
creation_time : 1970-01-01 00:00:00
handler_name : VideoHandler
Stream mapping:
Stream #0:0 -> #0:0 (h264 -> png)
Press [q] to stop, [?] for help
frame= 142 fps=1.0 q=0.0 Lsize=N/A time=00:19:00.93 bitrate=N/A
video:22992kB audio:0kB subtitle:0 global headers:0kB muxing overhead -100.000093%