【FFMPEG】6. ffmpeg命令參數說明

一、主要參數

◼ -i 設定輸入流
◼ -f 設定輸出格式(format)
◼ -ss 開始時間
◼ -t 時間長度

 

二、音頻參數：

◼ -aframes 設置要輸出的音頻幀數
◼ -b:a 音頻碼率
◼ -ar 設定採樣率
◼ -ac 設定聲音的Channel數
◼ -acodec 設定聲音編解碼器，如果用copy表示原始編解碼數據必須被拷貝。
◼ -an 不處理音頻
◼ -af 音頻過濾器

 

三、視頻參數：

◼ -vframes 設置要輸出的視頻幀數
◼ -b 設定視頻碼率
◼ -b:v 視頻碼率
◼ -r 設定幀速率
◼ -s 設定畫面的寬與高
◼ -vn 不處理視頻
◼ -aspect aspect 設置橫縱比 4:3 16:9 或 1.3333 1.7777
◼ -vcodec 設定視頻編解碼器，如果用copy表示原始編解碼數據必須被拷貝。
◼ -vf 視頻過濾器

 

四、實例

1. ffmpeg -i test.mp4 -vframes 300 -b:v 300k -r 30 -s 640x480 -aspect 16:9 -vcodec libx265 out.h265

D:\ffmpeg\test-av>ffmpeg -i test.mp4 -vframes 300 -b:v 300k -r 30 -s 640x480 -aspect 16:9 -vcodec libx264 out.h265
ffmpeg version 4.1 Copyright (c) 2000-2018 the FFmpeg developers
  built with gcc 8.2.1 (GCC) 20181017
  configuration: --disable-static --enable-shared --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth
  libavutil      56. 22.100 / 56. 22.100
  libavcodec     58. 35.100 / 58. 35.100
  libavformat    58. 20.100 / 58. 20.100
  libavdevice    58.  5.100 / 58.  5.100
  libavfilter     7. 40.101 /  7. 40.101
  libswscale      5.  3.100 /  5.  3.100
  libswresample   3.  3.100 /  3.  3.100
  libpostproc    55.  3.100 / 55.  3.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'test.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf58.20.100
  Duration: 00:01:00.08, start: 0.000000, bitrate: 382 kb/s
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 320x240, 247 kb/s, 25 fps, 25 tbr, 12800 tbn, 50 tbc (default)
    Metadata:
      handler_name    : VideoHandler
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 128 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
Stream mapping:
  Stream #0:0 -> #0:0 (h264 (native) -> h264 (libx264))
Press [q] to stop, [?] for help
[libx264 @ 0553e200] using SAR=4/3
[libx264 @ 0553e200] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2
[libx264 @ 0553e200] profile High, level 3.0, 4:2:0, 8-bit
Output #0, hevc, to 'out.h265':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf58.20.100
    Stream #0:0(und): Video: h264 (libx264), yuv420p, 640x480 [SAR 4:3 DAR 16:9], q=-1--1, 300 kb/s, 30 fps, 30 tbn, 30 tbc (default)
    Metadata:
      handler_name    : VideoHandler
      encoder         : Lavc58.35.100 libx264
    Side data:
      cpb: bitrate max/min/avg: 0/0/300000 buffer size: 0 vbv_delay: -1
frame=  300 fps=0.0 q=-1.0 Lsize=     381kB time=00:00:09.93 bitrate= 314.5kbits/s dup=50 drop=0 speed=17.2x
video:381kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.000000%
[libx264 @ 0553e200] frame I:3     Avg QP:26.24  size: 12538
[libx264 @ 0553e200] frame P:92    Avg QP:27.14  size:  2826
[libx264 @ 0553e200] frame B:205   Avg QP:32.43  size:   453
[libx264 @ 0553e200] consecutive B-frames:  1.3% 14.7% 24.0% 60.0%
[libx264 @ 0553e200] mb I  I16..4: 13.4% 81.4%  5.1%
[libx264 @ 0553e200] mb P  I16..4:  0.9%  4.1%  0.3%  P16..4: 43.1%  6.7%  2.3%  0.0%  0.0%    skip:42.6%
[libx264 @ 0553e200] mb B  I16..4:  0.0%  0.2%  0.0%  B16..8: 23.3%  0.6%  0.1%  direct: 0.3%  skip:75.6%  L0:43.8% L1:52.7% BI: 3.5%
[libx264 @ 0553e200] final ratefactor: 26.86
[libx264 @ 0553e200] 8x8 transform intra:79.6% inter:85.6%
[libx264 @ 0553e200] coded y,uvDC,uvAC intra: 62.5% 40.0% 5.8% inter: 5.0% 3.3% 0.0%
[libx264 @ 0553e200] i16 v,h,dc,p: 27% 29% 10% 34%
[libx264 @ 0553e200] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 34% 12% 14%  4%  5% 12%  4% 11%  5%
[libx264 @ 0553e200] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 39%  9% 12%  5%  6% 14%  4%  8%  3%
[libx264 @ 0553e200] i8c dc,h,v,p: 61% 14% 22%  3%
[libx264 @ 0553e200] Weighted P-Frames: Y:0.0% UV:0.0%
[libx264 @ 0553e200] ref P L0: 57.9% 18.1% 19.2%  4.7%
[libx264 @ 0553e200] ref B L0: 89.6%  9.1%  1.4%
[libx264 @ 0553e200] ref B L1: 97.3%  2.7%
[libx264 @ 0553e200] kb/s:312.42

 

2. ffmpeg -i test.mp4 -b:a 192k -ar 48000 -ac 2 -acodec libmp3lame -aframes 200 out.mp3

D:\ffmpeg\test-av>ffmpeg -i test.mp4 -b:a 192k -ar 48000 -ac 2 -acodec libmp3lame -aframes 200 out.mp3
ffmpeg version 4.1 Copyright (c) 2000-2018 the FFmpeg developers
  built with gcc 8.2.1 (GCC) 20181017
  configuration: --disable-static --enable-shared --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth
  libavutil      56. 22.100 / 56. 22.100
  libavcodec     58. 35.100 / 58. 35.100
  libavformat    58. 20.100 / 58. 20.100
  libavdevice    58.  5.100 / 58.  5.100
  libavfilter     7. 40.101 /  7. 40.101
  libswscale      5.  3.100 /  5.  3.100
  libswresample   3.  3.100 /  3.  3.100
  libpostproc    55.  3.100 / 55.  3.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'test.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf58.20.100
  Duration: 00:01:00.08, start: 0.000000, bitrate: 382 kb/s
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 320x240, 247 kb/s, 25 fps, 25 tbr, 12800 tbn, 50 tbc (default)
    Metadata:
      handler_name    : VideoHandler
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 128 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
Stream mapping:
  Stream #0:1 -> #0:0 (aac (native) -> mp3 (libmp3lame))
Press [q] to stop, [?] for help
Output #0, mp3, to 'out.mp3':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    TSSE            : Lavf58.20.100
    Stream #0:0(und): Audio: mp3 (libmp3lame), 48000 Hz, stereo, fltp, 192 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
      encoder         : Lavc58.35.100 libmp3lame
size=     113kB time=00:00:04.77 bitrate= 194.1kbits/s speed=  38x
video:0kB audio:112kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.628472%