Força o ffmpeg a usar 100% da CPU

0

Estou usando o ffmpeg para extrair quadros do vídeo, mas o processo é muito lento. Olhando para o uso da CPU, vejo que o ffmpeg usa apenas 50% da minha CPU. Eu também tentei adicionar -threads 4, mas parece que não tem nenhum efeito. Eu preciso maximizar a velocidade desse processo. Como posso fazer isso?

Update: Então eu fiz um teste, tentei primeiro converter um vídeo sozinho, tendo este resultado:

ffmpeg version N-71959-g9253cc4 Copyright (c) 2000-2015 the FFmpeg developers
  built with gcc 4.9.2 (GCC)
  configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libdcadec --enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-lzma --enable-decklink --enable-zlib
  libavutil      54. 23.101 / 54. 23.101
  libavcodec     56. 37.102 / 56. 37.102
  libavformat    56. 32.100 / 56. 32.100
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 16.101 /  5. 16.101
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  1.100 /  1.  1.100
  libpostproc    53.  3.100 / 53.  3.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'C:.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf55.33.100
  Duration: 00:30:23.13, start: 0.000000, bitrate: 573 kb/s
    Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p, 640x360 [SAR 1:1 DAR 16:9], 501 kb/s, 29.97 fps, 29.97 tbr, 11988 tbn, 59.94 tbc (default)
    Metadata:
      handler_name    : VideoHandler
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, mono, fltp, 32 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
    Stream #0:2(und): Data: none (rtp  / 0x20707472), 26 kb/s (default)
    Metadata:
      creation_time   : 2014-08-27 16:05:35
      handler_name    : GPAC ISO Hint Handler
    Stream #0:3(und): Data: none (rtp  / 0x20707472), 7 kb/s (default)
    Metadata:
      creation_time   : 2014-08-27 16:05:53
      handler_name    : GPAC ISO Hint Handler
[swscaler @ 0000000002e63360] deprecated pixel format used, make sure you did set range correctly
Output #0, image2, to 'C:\TEMP-%d.jpg':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf56.32.100
    Stream #0:0(und): Video: mjpeg, yuvj420p(pc), 640x360 [SAR 1:1 DAR 16:9], q=2-31, 200 kb/s, 1 fps, 1 tbn, 1 tbc (default)
    Metadata:
      handler_name    : VideoHandler
      encoder         : Lavc56.37.102 mjpeg
Stream mapping:
  Stream #0:0 -> #0:0 (h264 (native) -> mjpeg (native))
Press [q] to stop, [?] for help
frame=   15 fps=0.0 q=1.6 size=N/A time=00:00:15.00 bitrate=N/A dup=0 drop=384    
frame=   28 fps= 28 q=1.6 size=N/A time=00:00:28.00 bitrate=N/A dup=0 drop=763    
frame=   42 fps= 28 q=1.6 size=N/A time=00:00:42.00 bitrate=N/A dup=0 drop=1172    
frame=   55 fps= 27 q=1.6 size=N/A time=00:00:55.00 bitrate=N/A dup=0 drop=1529    
frame=   67 fps= 27 q=1.6 size=N/A time=00:01:07.00 bitrate=N/A dup=0 drop=1896    
frame=   80 fps= 27 q=1.6 size=N/A time=00:01:20.00 bitrate=N/A dup=0 drop=2267    
frame=   93 fps= 27 q=1.6 size=N/A time=00:01:33.00 bitrate=N/A dup=0 drop=2651    
frame=  106 fps= 26 q=1.6 size=N/A time=00:01:46.00 bitrate=N/A dup=0 drop=3025    
frame=  119 fps= 26 q=1.6 size=N/A time=00:01:59.00 bitrate=N/A dup=0 drop=3386    
frame=  131 fps= 26 q=1.6 size=N/A time=00:02:11.00 bitrate=N/A dup=0 drop=3757    
frame=  144 fps= 26 q=1.6 size=N/A time=00:02:24.00 bitrate=N/A dup=0 drop=4124    
frame=  157 fps= 26 q=1.6 size=N/A time=00:02:37.00 bitrate=N/A dup=0 drop=4487    
frame=  169 fps= 26 q=1.6 size=N/A time=00:02:49.00 bitrate=N/A dup=0 drop=4852    
frame=  182 fps= 26 q=1.6 size=N/A time=00:03:02.00 bitrate=N/A dup=0 drop=5226    
frame=  195 fps= 26 q=1.6 size=N/A time=00:03:15.00 bitrate=N/A dup=0 drop=5593    
frame=  209 fps= 26 q=1.6 size=N/A time=00:03:29.00 bitrate=N/A dup=0 drop=5990    
frame=  222 fps= 26 q=1.6 size=N/A time=00:03:42.00 bitrate=N/A dup=0 drop=6367    
frame=  235 fps= 26 q=1.6 size=N/A time=00:03:55.00 bitrate=N/A dup=0 drop=6753    
frame=  248 fps= 26 q=1.6 size=N/A time=00:04:08.00 bitrate=N/A dup=0 drop=7131    
frame=  261 fps= 26 q=1.6 size=N/A time=00:04:21.00 bitrate=N/A dup=0 drop=7497    
frame=  274 fps= 26 q=1.6 size=N/A time=00:04:34.00 bitrate=N/A dup=0 drop=7873    
frame=  287 fps= 26 q=1.6 size=N/A time=00:04:47.00 bitrate=N/A dup=0 drop=8255    
frame=  300 fps= 26 q=1.6 size=N/A time=00:05:00.00 bitrate=N/A dup=0 drop=8644    
frame=  314 fps= 26 q=1.6 size=N/A time=00:05:14.00 bitrate=N/A dup=0 drop=9036    
frame=  328 fps= 26 q=1.6 size=N/A time=00:05:28.00 bitrate=N/A dup=0 drop=9438    
frame=  340 fps= 26 q=1.6 size=N/A time=00:05:40.00 bitrate=N/A dup=0 drop=9813    
frame=  354 fps= 26 q=1.6 size=N/A time=00:05:54.00 bitrate=N/A dup=0 drop=10205    
frame=  367 fps= 26 q=1.6 size=N/A time=00:06:07.00 bitrate=N/A dup=0 drop=10585    
frame=  380 fps= 26 q=1.6 size=N/A time=00:06:20.00 bitrate=N/A dup=0 drop=10961    
frame=  394 fps= 26 q=1.6 size=N/A time=00:06:34.00 bitrate=N/A dup=0 drop=11360    
frame=  406 fps= 26 q=1.6 size=N/A time=00:06:46.00 bitrate=N/A dup=0 drop=11712    
frame=  420 fps= 26 q=1.6 size=N/A time=00:07:00.00 bitrate=N/A dup=0 drop=12103    
frame=  434 fps= 26 q=1.6 size=N/A time=00:07:14.00 bitrate=N/A dup=0 drop=12509    
frame=  447 fps= 26 q=1.6 size=N/A time=00:07:27.00 bitrate=N/A dup=0 drop=12888    
frame=  460 fps= 26 q=1.6 size=N/A time=00:07:40.00 bitrate=N/A dup=0 drop=13267    
frame=  473 fps= 26 q=1.6 size=N/A time=00:07:53.00 bitrate=N/A dup=0 drop=13640    
frame=  486 fps= 26 q=1.6 size=N/A time=00:08:06.00 bitrate=N/A dup=0 drop=14036    
frame=  500 fps= 26 q=1.6 size=N/A time=00:08:20.00 bitrate=N/A dup=0 drop=14421    
frame=  513 fps= 26 q=1.6 size=N/A time=00:08:33.00 bitrate=N/A dup=0 drop=14808    
frame=  526 fps= 26 q=1.6 size=N/A time=00:08:46.00 bitrate=N/A dup=0 drop=15197    
frame=  540 fps= 26 q=1.6 size=N/A time=00:09:00.00 bitrate=N/A dup=0 drop=15579    
frame=  552 fps= 26 q=1.6 size=N/A time=00:09:12.00 bitrate=N/A dup=0 drop=15948    
frame=  565 fps= 26 q=1.6 size=N/A time=00:09:25.00 bitrate=N/A dup=0 drop=16321    
frame=  579 fps= 26 q=1.6 size=N/A time=00:09:39.00 bitrate=N/A dup=0 drop=16725    
frame=  592 fps= 26 q=1.6 size=N/A time=00:09:52.00 bitrate=N/A dup=0 drop=17097    
frame=  605 fps= 26 q=1.6 size=N/A time=00:10:05.00 bitrate=N/A dup=0 drop=17462    
frame=  618 fps= 26 q=1.6 size=N/A time=00:10:18.00 bitrate=N/A dup=0 drop=17851    
frame=  631 fps= 26 q=1.6 size=N/A time=00:10:31.00 bitrate=N/A dup=0 drop=18225    
frame=  644 fps= 26 q=1.6 size=N/A time=00:10:44.00 bitrate=N/A dup=0 drop=18607    
frame=  657 fps= 26 q=1.6 size=N/A time=00:10:57.00 bitrate=N/A dup=0 drop=18969    
frame=  669 fps= 26 q=1.6 size=N/A time=00:11:09.00 bitrate=N/A dup=0 drop=19333    
frame=  681 fps= 26 q=1.6 size=N/A time=00:11:21.00 bitrate=N/A dup=0 drop=19681    
frame=  693 fps= 26 q=1.6 size=N/A time=00:11:33.00 bitrate=N/A dup=0 drop=20026    
frame=  706 fps= 26 q=1.6 size=N/A time=00:11:46.00 bitrate=N/A dup=0 drop=20402    
frame=  716 fps= 26 q=1.6 size=N/A time=00:11:56.00 bitrate=N/A dup=0 drop=20691    
frame=  726 fps= 26 q=1.6 size=N/A time=00:12:06.00 bitrate=N/A dup=0 drop=20985    
frame=  738 fps= 26 q=1.6 size=N/A time=00:12:18.00 bitrate=N/A dup=0 drop=21317    
frame=  751 fps= 26 q=1.6 size=N/A time=00:12:31.00 bitrate=N/A dup=0 drop=21692    
frame=  763 fps= 26 q=1.6 size=N/A time=00:12:43.00 bitrate=N/A dup=0 drop=22049    
frame=  775 fps= 26 q=1.6 size=N/A time=00:12:55.00 bitrate=N/A dup=0 drop=22403    
frame=  788 fps= 26 q=1.6 size=N/A time=00:13:08.00 bitrate=N/A dup=0 drop=22764    
frame=  801 fps= 26 q=1.6 size=N/A time=00:13:21.00 bitrate=N/A dup=0 drop=23149    
frame=  814 fps= 26 q=1.6 size=N/A time=00:13:34.00 bitrate=N/A dup=0 drop=23540    
frame=  828 fps= 26 q=1.6 size=N/A time=00:13:48.00 bitrate=N/A dup=0 drop=23937    
frame=  841 fps= 26 q=1.6 size=N/A time=00:14:01.00 bitrate=N/A dup=0 drop=24315    
frame=  854 fps= 26 q=1.6 size=N/A time=00:14:14.00 bitrate=N/A dup=0 drop=24694    
frame=  867 fps= 26 q=1.6 size=N/A time=00:14:27.00 bitrate=N/A dup=0 drop=25071    
frame=  881 fps= 26 q=1.6 size=N/A time=00:14:41.00 bitrate=N/A dup=0 drop=25458    
frame=  894 fps= 26 q=1.6 size=N/A time=00:14:54.00 bitrate=N/A dup=0 drop=25844    
frame=  908 fps= 26 q=1.6 size=N/A time=00:15:08.00 bitrate=N/A dup=0 drop=26240    
frame=  923 fps= 26 q=1.6 size=N/A time=00:15:23.00 bitrate=N/A dup=0 drop=26675    
frame=  935 fps= 26 q=1.6 size=N/A time=00:15:35.00 bitrate=N/A dup=0 drop=27038    
frame=  949 fps= 26 q=1.6 size=N/A time=00:15:49.00 bitrate=N/A dup=0 drop=27431    
frame=  961 fps= 26 q=1.6 size=N/A time=00:16:01.00 bitrate=N/A dup=0 drop=27776    
frame=  973 fps= 26 q=1.6 size=N/A time=00:16:13.00 bitrate=N/A dup=0 drop=28125    
frame=  985 fps= 26 q=1.6 size=N/A time=00:16:25.00 bitrate=N/A dup=0 drop=28477    
frame=  998 fps= 26 q=1.6 size=N/A time=00:16:38.00 bitrate=N/A dup=0 drop=28848    
frame= 1010 fps= 26 q=1.6 size=N/A time=00:16:50.00 bitrate=N/A dup=0 drop=29211    
frame= 1023 fps= 26 q=1.6 size=N/A time=00:17:03.00 bitrate=N/A dup=0 drop=29572    
frame= 1035 fps= 26 q=1.6 size=N/A time=00:17:15.00 bitrate=N/A dup=0 drop=29932    
frame= 1047 fps= 26 q=1.6 size=N/A time=00:17:27.00 bitrate=N/A dup=0 drop=30294    
frame= 1060 fps= 26 q=1.6 size=N/A time=00:17:40.00 bitrate=N/A dup=0 drop=30644    
frame= 1072 fps= 26 q=1.6 size=N/A time=00:17:52.00 bitrate=N/A dup=0 drop=31004    
frame= 1085 fps= 26 q=1.6 size=N/A time=00:18:05.00 bitrate=N/A dup=0 drop=31368    
frame= 1097 fps= 26 q=1.6 size=N/A time=00:18:17.00 bitrate=N/A dup=0 drop=31742    
frame= 1110 fps= 26 q=1.6 size=N/A time=00:18:30.00 bitrate=N/A dup=0 drop=32101    
frame= 1123 fps= 26 q=1.6 size=N/A time=00:18:43.00 bitrate=N/A dup=0 drop=32493    
frame= 1137 fps= 26 q=1.6 size=N/A time=00:18:57.00 bitrate=N/A dup=0 drop=32874    
frame= 1150 fps= 26 q=1.6 size=N/A time=00:19:10.00 bitrate=N/A dup=0 drop=33251    
frame= 1162 fps= 26 q=1.6 size=N/A time=00:19:22.00 bitrate=N/A dup=0 drop=33626    
frame= 1175 fps= 26 q=1.6 size=N/A time=00:19:35.00 bitrate=N/A dup=0 drop=33990    
frame= 1188 fps= 26 q=1.6 size=N/A time=00:19:48.00 bitrate=N/A dup=0 drop=34362    
frame= 1201 fps= 26 q=1.6 size=N/A time=00:20:01.00 bitrate=N/A dup=0 drop=34739    
frame= 1214 fps= 26 q=1.6 size=N/A time=00:20:14.00 bitrate=N/A dup=0 drop=35127    
frame= 1228 fps= 26 q=1.6 size=N/A time=00:20:28.00 bitrate=N/A dup=0 drop=35521    
frame= 1242 fps= 26 q=1.6 size=N/A time=00:20:42.00 bitrate=N/A dup=0 drop=35916    
frame= 1254 fps= 26 q=1.6 size=N/A time=00:20:54.00 bitrate=N/A dup=0 drop=36281    
frame= 1267 fps= 26 q=1.6 size=N/A time=00:21:07.00 bitrate=N/A dup=0 drop=36661    
frame= 1280 fps= 26 q=1.6 size=N/A time=00:21:20.00 bitrate=N/A dup=0 drop=37017    
frame= 1293 fps= 26 q=1.6 size=N/A time=00:21:33.00 bitrate=N/A dup=0 drop=37394    
frame= 1306 fps= 26 q=1.6 size=N/A time=00:21:46.00 bitrate=N/A dup=0 drop=37786    
frame= 1318 fps= 26 q=1.6 size=N/A time=00:21:58.00 bitrate=N/A dup=0 drop=38142    
frame= 1332 fps= 26 q=1.6 size=N/A time=00:22:12.00 bitrate=N/A dup=0 drop=38526    
frame= 1346 fps= 26 q=1.6 size=N/A time=00:22:26.00 bitrate=N/A dup=0 drop=38929    
frame= 1358 fps= 26 q=1.6 size=N/A time=00:22:38.00 bitrate=N/A dup=0 drop=39303    
frame= 1371 fps= 26 q=1.6 size=N/A time=00:22:51.00 bitrate=N/A dup=0 drop=39676    
frame= 1384 fps= 26 q=1.6 size=N/A time=00:23:04.00 bitrate=N/A dup=0 drop=40046    
frame= 1398 fps= 26 q=1.6 size=N/A time=00:23:18.00 bitrate=N/A dup=0 drop=40438    
frame= 1411 fps= 26 q=1.6 size=N/A time=00:23:31.00 bitrate=N/A dup=0 drop=40818    
frame= 1424 fps= 26 q=1.6 size=N/A time=00:23:44.00 bitrate=N/A dup=0 drop=41202    
frame= 1437 fps= 26 q=1.6 size=N/A time=00:23:57.00 bitrate=N/A dup=0 drop=41589    
frame= 1451 fps= 26 q=1.6 size=N/A time=00:24:11.00 bitrate=N/A dup=0 drop=41971    
frame= 1463 fps= 26 q=1.6 size=N/A time=00:24:23.00 bitrate=N/A dup=0 drop=42340    
frame= 1477 fps= 26 q=1.6 size=N/A time=00:24:37.00 bitrate=N/A dup=0 drop=42724    
frame= 1490 fps= 26 q=1.6 size=N/A time=00:24:50.00 bitrate=N/A dup=0 drop=43129    
frame= 1503 fps= 26 q=1.6 size=N/A time=00:25:03.00 bitrate=N/A dup=0 drop=43500    
frame= 1516 fps= 26 q=1.6 size=N/A time=00:25:16.00 bitrate=N/A dup=0 drop=43869    
frame= 1530 fps= 26 q=1.6 size=N/A time=00:25:30.00 bitrate=N/A dup=0 drop=44260    
frame= 1543 fps= 26 q=1.6 size=N/A time=00:25:43.00 bitrate=N/A dup=0 drop=44646    
frame= 1556 fps= 26 q=1.6 size=N/A time=00:25:56.00 bitrate=N/A dup=0 drop=45033    
frame= 1569 fps= 26 q=1.6 size=N/A time=00:26:09.00 bitrate=N/A dup=0 drop=45393    
frame= 1582 fps= 26 q=1.6 size=N/A time=00:26:22.00 bitrate=N/A dup=0 drop=45766    
frame= 1594 fps= 26 q=1.6 size=N/A time=00:26:34.00 bitrate=N/A dup=0 drop=46139    
frame= 1607 fps= 26 q=1.6 size=N/A time=00:26:47.00 bitrate=N/A dup=0 drop=46498    
frame= 1620 fps= 26 q=1.6 size=N/A time=00:27:00.00 bitrate=N/A dup=0 drop=46874    
frame= 1633 fps= 26 q=1.6 size=N/A time=00:27:13.00 bitrate=N/A dup=0 drop=47247    
frame= 1645 fps= 26 q=1.6 size=N/A time=00:27:25.00 bitrate=N/A dup=0 drop=47609    
frame= 1659 fps= 26 q=1.6 size=N/A time=00:27:39.00 bitrate=N/A dup=0 drop=48000    
frame= 1671 fps= 26 q=1.6 size=N/A time=00:27:51.00 bitrate=N/A dup=0 drop=48362    
frame= 1684 fps= 26 q=1.6 size=N/A time=00:28:04.00 bitrate=N/A dup=0 drop=48748    
frame= 1697 fps= 26 q=1.6 size=N/A time=00:28:17.00 bitrate=N/A dup=0 drop=49103    
frame= 1710 fps= 26 q=1.6 size=N/A time=00:28:30.00 bitrate=N/A dup=0 drop=49474    
frame= 1723 fps= 26 q=1.6 size=N/A time=00:28:43.00 bitrate=N/A dup=0 drop=49858    
frame= 1736 fps= 26 q=1.6 size=N/A time=00:28:56.00 bitrate=N/A dup=0 drop=50249    
frame= 1749 fps= 26 q=1.6 size=N/A time=00:29:09.00 bitrate=N/A dup=0 drop=50612    
frame= 1762 fps= 26 q=1.6 size=N/A time=00:29:22.00 bitrate=N/A dup=0 drop=50981    
frame= 1774 fps= 26 q=1.6 size=N/A time=00:29:34.00 bitrate=N/A dup=0 drop=51349    
frame= 1787 fps= 26 q=1.6 size=N/A time=00:29:47.00 bitrate=N/A dup=0 drop=51727    
frame= 1800 fps= 26 q=1.6 size=N/A time=00:30:00.00 bitrate=N/A dup=0 drop=52098    
frame= 1813 fps= 26 q=1.6 size=N/A time=00:30:13.00 bitrate=N/A dup=0 drop=52486    
frame= 1824 fps= 26 q=1.6 Lsize=N/A time=00:30:24.00 bitrate=N/A dup=0 drop=52798    
video:40987kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown

O processo inteiro levou 71 segundos com uma taxa de quadros de 26, uso da CPU de 50%.

Então eu tentei rodar a mesma conversão usando o mesmo vídeo, mas com 2 tarefas paralelas (basicamente convertendo 2 vezes e salvando imagens com 2 nomes diferentes). A taxa de quadros de cada vídeo era de cerca de 17 estáveis para cada vídeo, o uso da CPU era 45 para cada processo e o tempo total era de 105 segundos para o primeiro e 104 segundos para o outro. Portanto, executá-los um após o outro teria levado 70 + 70 = 140 segundos, enquanto executava 2 istances ao mesmo tempo, forçando o processador a trabalhar a 100% levou 105 segundos para converter ambos os vídeos, economizando 35 segundos, o que em larga escala são importantes.

    
por Hyperion 21.05.2015 / 14:22

1 resposta

1

Escrever muitos arquivos pequenos é lento. É por isso que a CPU não está com 100% de carga, mas o disco rígido provavelmente está.

É claro que não se trata de escrever com 100% de taxa de transferência possível, mas com que rapidez o disco pode atender a solicitações. Como a criação de arquivos envolve o acesso a muitas regiões do disco que podem ser separadas um pouco, a latência de acesso do seu disco é o gargalo aqui.

Não há nada que você possa fazer sobre isso, mas mudar para um SSD ou um SSD mais rápido. É muito improvável que o RAID0 ajude com cargas ligadas à latência.

    
por 21.05.2015 / 19:45