我在filtergraph描述中遇到了无效的文件索引1的问题

Question

这是我的代码：

ffmpeg -i wireframe-spendo.mov palette.png -filter_complex fps=25,scale=800:600:flags=lanczos[x],[x][1:v]paletteuse wireframe-spendo.gif

但之后：

ffmpeg -i wireframe-spendo.mov palette.png -filter_complex fps=25,scale=800:600:flags=lanczos[x],[x][1:v]paletteuse wireframe-spendo.gif
ffmpeg version 4.1.3 Copyright (c) 2000-2019 the FFmpeg developers
  built with Apple LLVM version 10.0.0 (clang-1000.11.45.5)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/4.1.3 --enable-shared --enable-pthreads --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags='-I/Library/Java/JavaVirtualMachines/openjdk-12.jdk/Contents/Home/include -I/Library/Java/JavaVirtualMachines/openjdk-12.jdk/Contents/Home/include/darwin' --host-ldflags= --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom --enable-libbluray --enable-libmp3lame --enable-libopus --enable-librubberband --enable-libsnappy --enable-libtesseract --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-libxvid --enable-lzma --enable-libfontconfig --enable-libfreetype --enable-frei0r --enable-libass --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librtmp --enable-libspeex --enable-videotoolbox --disable-libjack --disable-indev=jack --enable-libaom --enable-libsoxr
  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
  libavresample   4.  0.  0 /  4.  0.  0
  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 'wireframe-spendo.mov':
  Metadata:
    major_brand     : qt  
    minor_version   : 0
    compatible_brands: qt  
    creation_time   : 2019-04-17T09:38:24.000000Z
    com.apple.quicktime.make: Apple
    com.apple.quicktime.model: iMac12,2
    com.apple.quicktime.software: Mac OS X 10.13.6 (17G6029)
    com.apple.quicktime.creationdate: 2019-04-17T11:37:00+0200
  Duration: 00:00:16.42, start: 0.000000, bitrate: 3170 kb/s
    Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv, bt709), 1476x1074 [SAR 1:1 DAR 246:179], 3163 kb/s, 60 fps, 60 tbr, 6k tbn, 12k tbc (default)
    Metadata:
      creation_time   : 2019-04-17T09:38:24.000000Z
      handler_name    : Core Media Video
      encoder         : H.264

输出终端说：

Invalid file index 1 in filtergraph description fps=25,scale=800:600:flags=lanczos[x],[x][1:v]paletteuse.

Answer 1

你在-i之前忘记了第二个palette.png。

每个输入都需要自己的-i选项。