我正在尝试使用ffmpeg复杂滤镜缩放和模糊视频（部分）。实际上，这已经在生产中使用了多年。
我现在在Ubuntu 18.04上运行较新版本的ffmpeg，并收到与过滤器有关的错误，其中相同命令在Ubuntu 16.04的ffmpeg上针对同一视频运行正常。
具体来说，我看到以下错误：
mov,mp4,m4a,3gp,3g2,mj2 @ 0x56055a5902c0] Invalid stream specifier: vs0.
Last message repeated 1 times
Stream specifier 'vs0' in filtergraph description ... matches no streams.
关于复杂过滤器API的某些更改是否会使同一输入在ffmpeg的较新版本中无效？
有问题的命令仅在Bash终端中运行以下命令。
ffmpeg -ss 60 -i ~/test.mp4 -y -filter_complex "[0:v]scale=-2:'min(320,ih)'[vs0];[vs0]crop=in_w/9:in_h/2:0:0,boxblur=5:1:cr=3:ar=3[b0];[vs0]crop=in_w/9:in_h/2:in_w-out_w:0,boxblur=5:1:cr=3:ar=3[b1];[vs0]crop=(in_w-2*in_w/9):in_h/20:in_w/9:0,boxblur=5:1:cr=3:ar=3[b2];[vs0][b0]overlay=0:0[ovr0];[ovr0][b1]overlay=main_w-overlay_w:0[ovr1];[ovr1][b2]overlay=main_w/9:0[vs1]" -map [vs1] -an -ac 2 -b:a 128k -acodec aac -b:v 1024k -r 30 -vcodec libx264 -t 300 -y -preset slow -movflags faststart -pix_fmt yuv420p -f mp4 ~/out.mp4
如果我们分解复杂的filter语句，它看起来像：
[0:v]scale=-2:'min(320,ih)'[vs0];
[vs0]crop=in_w/9:in_h/2:0:0,boxblur=5:1:cr=3:ar=3[b0];
[vs0]crop=in_w/9:in_h/2:in_w-out_w:0,boxblur=5:1:cr=3:ar=3[b1];
[vs0]crop=(in_w-2*in_w/9):in_h/20:in_w/9:0,boxblur=5:1:cr=3:ar=3[b2];
[vs0][b0]overlay=0:0[ovr0];[ovr0][b1]overlay=main_w-overlay_w:0[ovr1];
[ovr1][b2]overlay=main_w/9:0[vs1]
在ffmpeg version N-86980-g62b7553（Ubuntu 16.04）上，一切工作都像过去几年一样出色。
$ ffmpeg -ss 60 -i ~/test.mp4 -y -filter_complex "[0:v]scale=-2:'min(320,ih)'[vs0];[vs0]crop=in_w/9:in_h/2:0:0,boxblur=5:1:cr=3:ar=3[b0];[vs0]crop=in_w/9:in_h/2:in_w-out_w:0,boxblur=5:1:cr=3:ar=3[b1];[vs0]crop=(in_w-2*in_w/9):in_h/20:in_w/9:0,boxblur=5:1:cr=3:ar=3[b2];[vs0][b0]overlay=0:0[ovr0];[ovr0][b1]overlay=main_w-overlay_w:0[ovr1];[ovr1][b2]overlay=main_w/9:0[vs1]" -map [vs1] -an -ac 2 -b:a 128k -acodec aac -b:v 1024k -r 30 -vcodec libx264 -t 300 -y -preset slow -movflags faststart -pix_fmt yuv420p -f mp4 ~/out.mp4
ffmpeg version N-86980-g62b7553 Copyright (c) 2000-2017 the FFmpeg developers
built with gcc 5.4.0 (Ubuntu 5.4.0-6ubuntu1~16.04.4) 20160609
configuration: --prefix=/root/ffmpeg_build --pkg-config-flags=--static --extra-cflags=-I/root/ffmpeg_build/include --extra-ldflags=-L/root/ffmpeg_build/lib --bindir=/root/bin --enable-gpl --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-openssl --enable-nonfree
libavutil 55. 73.100 / 55. 73.100
libavcodec 57.102.100 / 57.102.100
libavformat 57. 76.100 / 57. 76.100
libavdevice 57. 7.100 / 57. 7.100
libavfilter 6. 98.100 / 6. 98.100
libswscale 4. 7.102 / 4. 7.102
libswresample 2. 8.100 / 2. 8.100
libpostproc 54. 6.100 / 54. 6.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/home/cmaier/test.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf57.76.100
Duration: 00:10:00.00, start: 0.000000, bitrate: 1036 kb/s
Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 768x480, 1033 kb/s, 30 fps, 30 tbr, 15360 tbn, 60 tbc (default)
Metadata:
handler_name : VideoHandler
Stream mapping:
Stream #0:0 (h264) -> scale
Stream #0:0 (h264) -> crop
Stream #0:0 (h264) -> crop
Stream #0:0 (h264) -> overlay:main
overlay -> Stream #0:0 (libx264)
Press [q] to stop, [?] for help
[libx264 @ 0x27b2ca0] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 AVX2 LZCNT BMI2
[libx264 @ 0x27b2ca0] profile High, level 3.1
[libx264 @ 0x27b2ca0] 264 - core 148 r2643 5c65704 - H.264/MPEG-4 AVC codec - Copyleft 2003-2015 - http://www.videolan.org/x264.html - options: cabac=1 ref=5 deblock=1:0:0 analyse=0x3:0x113 me=umh subme=8 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=12 lookahead_threads=2 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=2 b_bias=0 direct=3 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=50 rc=abr mbtree=1 bitrate=1024 ratetol=1.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
Output #0, mp4, to '/home/cmaier/out.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf57.76.100
Stream #0:0: Video: h264 (libx264) (avc1 / 0x31637661), yuv420p, 768x480, q=-1--1, 1024 kb/s, 30 fps, 15360 tbn, 30 tbc (default)
Metadata:
encoder : Lavc57.102.100 libx264
Side data:
cpb: bitrate max/min/avg: 0/0/1024000 buffer size: 0 vbv_delay: -1
[mp4 @ 0x27b5a60] Starting second pass: moving the moov atom to the beginning of the file3.9x
frame= 9000 fps=117 q=-1.0 Lsize= 37827kB time=00:04:59.90 bitrate=1033.3kbits/s speed= 3.9x
video:37721kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.282333%
[libx264 @ 0x27b2ca0] frame I:36 Avg QP:15.21 size: 50944
[libx264 @ 0x27b2ca0] frame P:2723 Avg QP:20.12 size: 9593
[libx264 @ 0x27b2ca0] frame B:6241 Avg QP:24.23 size: 1710
[libx264 @ 0x27b2ca0] consecutive B-frames: 3.6% 6.9% 14.5% 75.0%
[libx264 @ 0x27b2ca0] mb I I16..4: 17.3% 58.5% 24.2%
[libx264 @ 0x27b2ca0] mb P I16..4: 0.5% 4.4% 0.9% P16..4: 31.1% 20.7% 12.1% 0.0% 0.0% skip:30.3%
[libx264 @ 0x27b2ca0] mb B I16..4: 0.0% 0.3% 0.1% B16..8: 28.9% 5.5% 1.1% direct: 1.1% skip:63.1% L0:37.5% L1:52.6% BI: 9.9%
[libx264 @ 0x27b2ca0] final ratefactor: 19.69
[libx264 @ 0x27b2ca0] 8x8 transform intra:72.8% inter:68.3%
[libx264 @ 0x27b2ca0] direct mvs spatial:99.9% temporal:0.1%
[libx264 @ 0x27b2ca0] coded y,uvDC,uvAC intra: 74.5% 73.0% 30.4% inter: 13.0% 10.7% 0.2%
[libx264 @ 0x27b2ca0] i16 v,h,dc,p: 49% 30% 3% 17%
[libx264 @ 0x27b2ca0] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 7% 14% 11% 7% 11% 8% 19% 8% 15%
[libx264 @ 0x27b2ca0] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 9% 13% 5% 8% 14% 10% 17% 9% 16%
[libx264 @ 0x27b2ca0] i8c dc,h,v,p: 42% 29% 15% 15%
[libx264 @ 0x27b2ca0] Weighted P-Frames: Y:7.4% UV:2.9%
[libx264 @ 0x27b2ca0] ref P L0: 59.2% 20.2% 11.5% 3.7% 4.3% 1.0% 0.1%
[libx264 @ 0x27b2ca0] ref B L0: 87.5% 8.8% 2.7% 1.0%
[libx264 @ 0x27b2ca0] ref B L1: 96.5% 3.5%
[libx264 @ 0x27b2ca0] kb/s:1030.01
在ffmpeg version N-93862-gf49cec2（Ubuntu 18.04）上，命令立即失败。
# ffmpeg -ss 60 -i ~/test.mp4 -y -filter_complex "[0:v]scale=-2:'min(320,ih)'[vs0];[vs0]crop=in_w/9:in_h/2:0:0,boxblur=5:1:cr=3:ar=3[b0];[vs0]crop=in_w/9:in_h/2:in_w-out_w:0,boxblur=5:1:cr=3:ar=3[b1];[vs0]crop=(in_w-2*in_w/9):in_h/20:in_w/9:0,boxblur=5:1:cr=3:ar=3[b2];[vs0][b0]overlay=0:0[ovr0];[ovr0][b1]overlay=main_w-overlay_w:0[ovr1];[ovr1][b2]overlay=main_w/9:0[vs1]" -map [vs1] -an -ac 2 -b:a 128k -acodec aac -b:v 1024k -r 30 -vcodec libx264 -t 300 -y -preset slow -movflags faststart -pix_fmt yuv420p -f mp4 ~/out.mp4
ffmpeg version N-93862-gf49cec2 Copyright (c) 2000-2019 the FFmpeg developers
built with gcc 7 (Ubuntu 7.4.0-1ubuntu1~18.04)
configuration: --prefix=/root/ffmpeg_build --pkg-config-flags=--static --extra-cflags=-I/root/ffmpeg_build/include --extra-ldflags=-L/root/ffmpeg_build/lib --bindir=/root/bin --enable-gpl --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-openssl --enable-nonfree
libavutil 56. 27.100 / 56. 27.100
libavcodec 58. 52.101 / 58. 52.101
libavformat 58. 27.103 / 58. 27.103
libavdevice 58. 7.100 / 58. 7.100
libavfilter 7. 53.100 / 7. 53.100
libswscale 5. 4.101 / 5. 4.101
libswresample 3. 4.100 / 3. 4.100
libpostproc 55. 4.100 / 55. 4.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/root/test.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf57.76.100
Duration: 00:10:00.00, start: 0.000000, bitrate: 1036 kb/s
Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 768x480, 1033 kb/s, 30 fps, 30 tbr, 15360 tbn, 60 tbc (default)
Metadata:
handler_name : VideoHandler
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x56055a5902c0] Invalid stream specifier: vs0.
Last message repeated 1 times
Stream specifier 'vs0' in filtergraph description [0:v]scale=-2:'min(320,ih)'[vs0];[vs0]crop=in_w/9:in_h/2:0:0,boxblur=5:1:cr=3:ar=3[b0];[vs0]crop=in_w/9:in_h/2:in_w-out_w:0,boxblur=5:1:cr=3:ar=3[b1];[vs0]crop=(in_w-2*in_w/9):in_h/20:in_w/9:0,boxblur=5:1:cr=3:ar=3[b2];[vs0][b0]overlay=0:0[ovr0];[ovr0][b1]overlay=main_w-overlay_w:0[ovr1];[ovr1][b2]overlay=main_w/9:0[vs1] matches no streams.