[FFmpeg-user] How to speed up thumbnail generation for video files using FFMPEG on MIPS

[Pavan Kulkarni]

>
> Hi,
>
Tried as per Carl's suggestion by using the latest version and
cross-compiling for MIPS.
Unfortunately though, the time taken to produce the thumbnail has not
reduced when compared with the case where select filter is used. (Below is
the uncut console o/p). There are also a few errors/warnings. How can I
resolve those?
However, the problem where I used to get a blank thumbnail when select
filter was not used is resolved by migrating to the newer version of
FFMPEG.
As an aside, Perhaps if I can get an option/combination of options in
ffmpeg where in I can seek to x seconds quickly and then search for the
closest I frame, then maybe I can get the thumbnail quicker?
Thanks a lot for the help so far!

time ./ffmpeg -ss 18 -i Pirates_remux_short.ts  -an -s 150x100 thumb12.jpg
ffmpeg version N-42364-g07df939 Copyright (c) 2000-2012 the FFmpeg
developers
  built on Jul  9 2012 15:46:44 with gcc 4.3.2
  configuration: --prefix=/home/pavank/ffmpeg/ffmpeg_cross_compiled
--enable-shared --enable-cross-compile --target-os=linux
--cross-prefix=mipsisa32r2el-timesys-linux-gnu- --arch=mips
--extra-cflags=-O2
  libavutil      51. 64.100 / 51. 64.100
  libavcodec     54. 33.100 / 54. 33.100
  libavformat    54. 15.102 / 54. 15.102
  libavdevice    54.  1.100 / 54.  1.100
  libavfilter     3.  1.100 /  3.  1.100
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0. 15.100 /  0. 15.100
[h264 @ 0x443ff0] non-existing SPS 13 referenced in buffering period
    Last message repeated 1 times


[NULL @ 0x443ff0] non-existing SPS 13 referenced in buffering period
    Last message repeated 7 times


Input #0, mpegts, from 'Pirates_remux_short.ts':
  Duration: 00:00:59.22, start: 720.665000, bitrate: 33719 kb/s
  Program 1
    Stream #0:0[0x1011]: Video: h264 (High) ([27][0][0][0] / 0x001B),
yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], 23.98 fps, 23.98 tbr, 90k tbn, 47.95
tbc
    Stream #0:1[0x1100](eng): Audio: pcm_bluray (HDMV / 0x564D4448), 48000
Hz, 5.1(side), s32, 6912 kb/s
[graph 0 input from stream 0:0 @ 0x447580] w:1920 h:1080 pixfmt:yuv420p
tb:1/90000 fr:24000/1001 sar:1/1 sws_param:flags=2
[output stream 0:0 @ 0x447930] No opaque field provided
[scaler for output stream 0:0 @ 0x447770] w:1920 h:1080 fmt:yuv420p sar:1/1
-> w:150 h:100 fmt:yuvj420p sar:32/27 flags:0x4

[h264 @ 0x443ff0] non-existing SPS 13 referenced in buffering period
Output #0, image2, to 'thumb12.jpg':


  Metadata:
    encoder         : Lavf54.15.102
    Stream #0:0: Video: mjpeg, yuvj420p, 150x100 [SAR 32:27 DAR 16:9],
q=2-31, 200 kb/s, 90k tbn, 23.98 tbc
Stream mapping:
  Stream #0:0 -> #0:0 (h264 -> mjpeg)
Press [q] to stop, [?] for help
[h264 @ 0x443ff0] non-existing SPS 13 referenced in buffering period
[h264 @ 0x443ff0] Missing reference picture


[h264 @ 0x443ff0] decode_slice_header error


[h264 @ 0x443ff0] Missing reference picture


[h264 @ 0x443ff0] decode_slice_header error


[h264 @ 0x443ff0] Missing reference picture


[h264 @ 0x443ff0] decode_slice_header error


[h264 @ 0x443ff0] Missing reference picture


[h264 @ 0x443ff0] decode_slice_header error


[h264 @ 0x443ff0] concealing 8160 DC, 8160 AC, 8160 MV errors


[h264 @ 0x443ff0] Missing reference picture
    Last message repeated 3 times


Could not get frame filename number 2 from pattern 'thumb12.jpg'te=
0.0kbits/s
av_interleaved_write_frame(): Invalid argument


Command exited with non-zero status 1


real    0m 34.41s
user    0m 28.21s
sys     0m 2.08s

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