使用ffmpeg将介绍图像开始合并到视频后如何保持视频质量

如何解决使用ffmpeg将介绍图像开始合并到视频后如何保持视频质量

我选择了高分辨率视频，但是一旦我运行命令，视频分辨率质量就发生了变化，而我得到的视频质量太差，作为输出视频，但我不想失去我的视频质量。让我在下面分享完整的命令和完整的日志：

注意：libx264 编码器不支持 iOS，我收到失败错误，所以我使用 h264_videotoolBox 所以我想使用 h264_videotoolBox 编码器获得支持的命令

命令：

ffmpeg -i test.MOV -loop 1 -t 5 -i 2.jpg -f lavfi -t 5 -i anullsrc -filter_complex "[0:v]trim=0:5,drawBox=t=fill[base];[1][base]scale2ref=iw:ih:force_original_aspect_ratio=decrease:flags=spline[2nd][base2];[ base2][2nd]overlay='(Ww)/2':'(Hh)/2'[padded];[padded][2:a][0:v][0:a]concat=n=2: v=1:a=1[v][a]" -c:v h264_videotoolBox -c:a aac -map "[v]" -map "[a]" output.mp4

完整日志

ffmpeg version 4.4 copyright (c) 2000-2021 the FFmpeg developers
  built with Apple clang version 12.0.0 (clang-1200.0.32.29)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/4.4_1 --enable-shared --enable-pthreads --enable-version3 --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom --enable-libbluray --enable-libdav1d --enable-libmp3lame --enable-libopus --enable-librav1e --enable-librubberband --enable-libsnappy --enable-libsrt --enable-libtesseract --enable-libtheora --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libxvid --enable-lzma --enable-libfontconfig --enable-libfreetype --enable-frei0r --enable-libass --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libspeex --enable-libsoxr --enable-libzmq --enable-libzimg --disable-libjack --disable-indev=jack --enable-videotoolBox
  libavutil      56. 70.100 / 56. 70.100
  libavcodec     58.134.100 / 58.134.100
  libavformat    58. 76.100 / 58. 76.100
  libavdevice    58. 13.100 / 58. 13.100
  libavfilter     7.110.100 /  7.110.100
  libavresample   4.  0.  0 /  4.  0.  0
  libswscale      5.  9.100 /  5.  9.100
  libswresample   3.  9.100 /  3.  9.100
  libpostproc    55.  9.100 / 55.  9.100
Input #0,mov,mp4,m4a,3gp,3g2,mj2,from 'test.MOV':
  Metadata:
    major_brand     : qt  
    minor_version   : 0
    compatible_brands: qt  
    creation_time   : 2021-03-07T06:36:17.000000Z
    com.apple.quicktime.location.accuracy.horizontal: 30.000000
    com.apple.quicktime.location.ISO6709: +23.1141+072.5768+061.729/
    com.apple.quicktime.make: Apple
    com.apple.quicktime.model: iPhone 6s
    com.apple.quicktime.software: 14.3
    com.apple.quicktime.creationdate: 2021-03-07T12:06:17+0530
  Duration: 00:00:29.79,start: 0.000000,bitrate: 15778 kb/s
  Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661),yuv420p(tv,bt709),1920x1080,15643 kb/s,29.98 fps,29.97 tbr,600 tbn,1200 tbc (default)
    Metadata:
      creation_time   : 2021-03-07T06:36:17.000000Z
      handler_name    : Core Media Video
      vendor_id       : [0][0][0][0]
      encoder         : H.264
  Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D),44100 Hz,mono,fltp,89 kb/s (default)
    Metadata:
      creation_time   : 2021-03-07T06:36:17.000000Z
      handler_name    : Core Media Audio
      vendor_id       : [0][0][0][0]
  Stream #0:2(und): Data: none (mebx / 0x7862656D),0 kb/s (default)
    Metadata:
      creation_time   : 2021-03-07T06:36:17.000000Z
      handler_name    : Core Media Metadata
  Stream #0:3(und): Data: none (mebx / 0x7862656D),0 kb/s (default)
    Metadata:
      creation_time   : 2021-03-07T06:36:17.000000Z
      handler_name    : Core Media Metadata
  Stream #0:4(und): Data: none (mebx / 0x7862656D),34 kb/s (default)
    Metadata:
      creation_time   : 2021-03-07T06:36:17.000000Z
      handler_name    : Core Media Metadata
Input #1,image2,from '2.jpg':
  Duration: 00:00:00.04,bitrate: 17347 kb/s
  Stream #1:0: Video: mjpeg (Baseline),yuvj444p(pc,bt470bg/unkNown/unkNown),360x360 [SAR 72:72 DAR 1:1],25 fps,25 tbr,25 tbn,25 tbc
Input #2,lavfi,from 'anullsrc':
  Duration: N/A,bitrate: 705 kb/s
  Stream #2:0: Audio: pcm_u8,stereo,u8,705 kb/s
Stream mapping:
  Stream #0:0 (h264) -> trim
  Stream #0:0 (h264) -> concat:in1:v0
  Stream #0:1 (aac) -> concat:in1:a0
  Stream #1:0 (mjpeg) -> scale2ref:default
  Stream #2:0 (pcm_u8) -> concat:in0:a0
  concat:out:v0 -> Stream #0:0 (h264_videotoolBox)
  concat:out:a0 -> Stream #0:1 (aac)
Press [q] to stop,[?] for help
[swscaler @ 0x7f976242b000] deprecated pixel format used,make sure you did set range correctly
Output #0,to 'output.mp4':
  Metadata:
    major_brand     : qt  
    minor_version   : 0
    compatible_brands: qt  
    com.apple.quicktime.creationdate: 2021-03-07T12:06:17+0530
    com.apple.quicktime.location.accuracy.horizontal: 30.000000
    com.apple.quicktime.location.ISO6709: +23.1141+072.5768+061.729/
    com.apple.quicktime.make: Apple
    com.apple.quicktime.model: iPhone 6s
    com.apple.quicktime.software: 14.3
    encoder         : Lavf58.76.100
  Stream #0:0: Video: h264 (avc1 / 0x31637661),bt709,progressive),q=2-31,200 kb/s,29.97 fps,30k tbn (default)
    Metadata:
      encoder         : Lavc58.134.100 h264_videotoolBox
  Stream #0:1: Audio: aac (LC) (mp4a / 0x6134706D),69 kb/s (default)
    Metadata:
      encoder         : Lavc58.134.100 aac
frame=    1 fps=0.0 q=0.0 size=       0kB time=00:00:00.00 bitrate=N/A speed=   frame=   12 fps=0.0 q=-0.0 size=     256kB time=00:00:00.32 bitrate=6452.4kbits/frame=   34 fps= 32 q=-0.0 size=     256kB time=00:00:01.02 bitrate=2053.0kbits/frame=   55 fps= 35 q=-0.0 size=     256kB time=00:00:01.74 bitrate=1204.4kbits/frame=   76 fps= 37 q=-0.0 size=     256kB time=00:00:02.46 bitrate= 852.2kbits/frame=   98 fps= 38 q=-0.0 size=     256kB time=00:00:03.18 bitrate= 659.4kbits/frame=  120 fps= 39 q=-0.0 size=     256kB time=00:00:03.90 bitrate= 537.7kbits/frame=  141 fps= 39 q=-0.0 size=     512kB time=00:00:04.62 bitrate= 907.8kbits/[out_0_0 @ 0x7f975de0ae80] 100 buffers queued in out_0_0,something may be wrong.
[out_0_1 @ 0x7f975de0a5c0] 100 buffers queued in out_0_1,something may be wrong.
frame=  301 fps= 67 q=-0.0 size=     768kB time=00:00:11.09 bitrate= 566.9kbits/frame=  406 fps= 81 q=-0.0 size=    1024kB time=00:00:14.60 bitrate= 574.4kbits/frame=  509 fps= 92 q=-0.0 size=    1280kB time=00:00:18.04 bitrate= 581.2kbits/frame=  604 fps=100 q=-0.0 size=    1792kB time=00:00:21.19 bitrate= 692.5kbits/frame=  705 fps=108 q=-0.0 size=    2048kB time=00:00:24.56 bitrate= 682.9kbits/frame=  809 fps=115 q=-0.0 size=    2304kB time=00:00:28.04 bitrate= 672.9kbits/frame=  909 fps=121 q=-0.0 size=    2816kB time=00:00:31.37 bitrate= 735.4kbits/frame= 1012 fps=126 q=-0.0 size=    3072kB time=00:00:34.71 bitrate= 725.0kbits/frame= 1043 fps=127 q=-0.0 Lsize=    3288kB time=00:00:34.78 bitrate= 774.3kbits/s speed=4.23x    
video:2995kB audio:255kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 1.168448%
[aac @ 0x7f9760024200] Qavg: 9569.656

解决方法

主视频的比特率约为 15778K，这是质量高的信号...

持续时间：00:00:29.79，开始：0.000000，比特率：15778 kb/s

你必须在你的代码中加入比特率参数 -b:v {bitrate,in this case 15778K} 以保持高品质，比如

ffmpeg -i test.MOV -loop 1 -t 5 -i 2.jpg -f lavfi -t 5 -i anullsrc -filter_complex "[0:v]trim=0:5,drawbox=t=fill[base];[1][base]scale2ref=iw:ih:force_original_aspect_ratio=decrease:flags=spline[2nd][base2];[base2][2nd]overlay='(W-w)/2':'(H-h)/2'[padded];[padded][2:a][0:v][0:a]concat=n=2:v=1:a=1[v][a]" -c:v h264_videotoolbox -b:v 15778K -c:a aac -map "[v]" -map "[a]" output.mp4

---

注意：如果“-c:a aac”参数有错误，请将其删除，因为在 Apple 的操作系统中 aac 是默认的，因为它是 Apple 编解码器

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