使用 -ffmpeg- 将音频混合并叠加到 4x4 视频中
Mixing and overlaying audio into a 4x4 video with -ffmpeg-
感谢@llogan 对我的 post here 的回复，我已经能够将 16 个不同的视频合并到一部 4x4 .mp4 电影中。
不幸的是，我还希望从这 16 个剪辑 中添加 音频 并叠加它们 。按原样使用代码，它从调用中声明的第一个剪辑中获取音频。
我试过了：
ffmpeg -i a.mp4 -i b.mp4 -i c.mp4 -i d.mp4 -i e.mp4 -i f.mp4 -i g.mp4 -i h.mp4 -i i.mp4 -i j.mp4 -i k.mp4 -i l.mp4 -i m.mp4 -i n.mp4 -i o.mp4 -i q.mp4 -i p.mp4 \
-filter_complex \
"[0:v]scale=iw/4:-1[v0];[1:v]scale=iw/4:-1[v1];[2:v]scale=iw/4:-1[v2]; \
[3:v]scale=iw/4:-1[v3];[4:v]scale=iw/4:-1[v4];[5:v]scale=iw/4:-1[v5]; \
[6:v]scale=iw/4:-1[v6];[7:v]scale=iw/4:-1[v7];[8:v]scale=iw/4:-1[v8]; \
[9:v]scale=iw/4:-1[v9];[10:v]scale=iw/4:-1[v10];[11:v]scale=iw/4:-1[v11]; \
[12:v]scale=iw/4:-1[v12];[13:v]scale=iw/4:-1[v13];[14:v]scale=iw/4:-1[v14]; \
[15:v]scale=iw/4:-1[v15]; \
[v0][v1][v2][v3][v4][v5][v6][v7][v8][v9][v10][v11][v12][v13][v14]
[v15]xstack=inputs=16:layout=0_0|w0_0|w0+w1_0|w0+w1+w2_0|0_h0|w4_h0|w4+w5_h0|w4+w5+w6_h0|0_h0+h4|w8_h0+h4|w8+w9_h0+h4|w8+w9+w10_h0+h4|0_h0+h4+h8|w12_h0+h4+h8|w12+w13_h0+h4+h8|w12+w13+w14_h0+h4+h8; \
[0:a][1:a][2:a][3:a][4:a][5:a][6:a][7:a][8:a][9:a][10:a][11:a][12:a][13:a][14:a][15:a]amerge=inputs=16[a]" \
-map "[a]" -ac 2 \
output.mp4
同时合并倒数第三行作为合并音频输入的尝试，但它产生：
ffmpeg version 4.3.2-0+deb11u1ubuntu1 Copyright (c) 2000-2021 the FFmpeg developers
built with gcc 10 (Ubuntu 10.2.1-20ubuntu1)
configuration: --prefix=/usr --extra-version=0+deb11u1ubuntu1 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --arch=amd64 --enable-gpl --disable-stripping --enable-avresample --disable-filter=resample --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libdav1d --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librabbitmq --enable-librsvg --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-sdl2 --enable-pocketsphinx --enable-libmfx --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-nvenc --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared
WARNING: library configuration mismatch
avcodec configuration: --prefix=/usr --extra-version=0+deb11u1ubuntu1 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --arch=amd64 --enable-gpl --disable-stripping --enable-avresample --disable-filter=resample --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libdav1d --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librabbitmq --enable-librsvg --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-sdl2 --enable-pocketsphinx --enable-libmfx --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-nvenc --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared --enable-version3 --disable-doc --disable-programs --enable-libaribb24 --enable-liblensfun --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libtesseract --enable-libvo_amrwbenc
libavutil 56. 51.100 / 56. 51.100
libavcodec 58. 91.100 / 58. 91.100
libavformat 58. 45.100 / 58. 45.100
libavdevice 58. 10.100 / 58. 10.100
libavfilter 7. 85.100 / 7. 85.100
libavresample 4. 0. 0 / 4. 0. 0
libswscale 5. 7.100 / 5. 7.100
libswresample 3. 7.100 / 3. 7.100
libpostproc 55. 7.100 / 55. 7.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'ang.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:10.00, start: 0.000000, bitrate: 480 kb/s
Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 271 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 194 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #1, mov,mp4,m4a,3gp,3g2,mj2, from 'atv.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:17.00, start: 0.000000, bitrate: 259 kb/s
Stream #1:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 53 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #1:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 193 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #2, mov,mp4,m4a,3gp,3g2,mj2, from 'bor.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:09.00, start: 0.000000, bitrate: 255 kb/s
Stream #2:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 48 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #2:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 192 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #3, mov,mp4,m4a,3gp,3g2,mj2, from 'cen.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:07.00, start: 0.000000, bitrate: 461 kb/s
Stream #3:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 250 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #3:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 196 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #4, mov,mp4,m4a,3gp,3g2,mj2, from 'cha.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:05.00, start: 0.000000, bitrate: 267 kb/s
Stream #4:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 59 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #4:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 194 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #5, mov,mp4,m4a,3gp,3g2,mj2, from 'grd.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:07.00, start: 0.000000, bitrate: 235 kb/s
Stream #5:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 28 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #5:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 193 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #6, mov,mp4,m4a,3gp,3g2,mj2, from 'grm.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:09.00, start: 0.000000, bitrate: 294 kb/s
Stream #6:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 86 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #6:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 195 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #7, mov,mp4,m4a,3gp,3g2,mj2, from 'htv.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:12.01, start: 0.000000, bitrate: 238 kb/s
Stream #7:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 29 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #7:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 196 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #8, mov,mp4,m4a,3gp,3g2,mj2, from 'lwt.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:10.00, start: 0.000000, bitrate: 239 kb/s
Stream #8:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 30 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #8:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 195 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #9, mov,mp4,m4a,3gp,3g2,mj2, from 'sou.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:08.00, start: 0.000000, bitrate: 247 kb/s
Stream #9:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 39 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #9:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 194 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #10, mov,mp4,m4a,3gp,3g2,mj2, from 'stv.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:09.00, start: 0.000000, bitrate: 257 kb/s
Stream #10:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 51 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #10:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 192 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #11, mov,mp4,m4a,3gp,3g2,mj2, from 'tha.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:06.00, start: 0.000000, bitrate: 454 kb/s
Stream #11:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 245 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #11:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 194 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #12, mov,mp4,m4a,3gp,3g2,mj2, from 'ttt.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:10.01, start: 0.000000, bitrate: 258 kb/s
Stream #12:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 51 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #12:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 193 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #13, mov,mp4,m4a,3gp,3g2,mj2, from 'utv.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:08.00, start: 0.000000, bitrate: 443 kb/s
Stream #13:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 234 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #13:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 194 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #14, mov,mp4,m4a,3gp,3g2,mj2, from 'wtv.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:08.00, start: 0.000000, bitrate: 431 kb/s
Stream #14:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 224 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #14:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 194 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #15, mov,mp4,m4a,3gp,3g2,mj2, from 'ytv.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:08.00, start: 0.000000, bitrate: 332 kb/s
Stream #15:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 123 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #15:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 195 kb/s (default)
Metadata:
handler_name : SoundHandler
File 'output.mp4' already exists. Overwrite? [y/N] y
Stream mapping:
Stream #0:0 (h264) -> scale
Stream #0:1 (aac) -> amerge:in0
Stream #1:0 (h264) -> scale
Stream #1:1 (aac) -> amerge:in1
Stream #2:0 (h264) -> scale
Stream #2:1 (aac) -> amerge:in2
Stream #3:0 (h264) -> scale
Stream #3:1 (aac) -> amerge:in3
Stream #4:0 (h264) -> scale
Stream #4:1 (aac) -> amerge:in4
Stream #5:0 (h264) -> scale
Stream #5:1 (aac) -> amerge:in5
Stream #6:0 (h264) -> scale
Stream #6:1 (aac) -> amerge:in6
Stream #7:0 (h264) -> scale
Stream #7:1 (aac) -> amerge:in7
Stream #8:0 (h264) -> scale
Stream #8:1 (aac) -> amerge:in8
Stream #9:0 (h264) -> scale
Stream #9:1 (aac) -> amerge:in9
Stream #10:0 (h264) -> scale
Stream #10:1 (aac) -> amerge:in10
Stream #11:0 (h264) -> scale
Stream #11:1 (aac) -> amerge:in11
Stream #12:0 (h264) -> scale
Stream #12:1 (aac) -> amerge:in12
Stream #13:0 (h264) -> scale
Stream #13:1 (aac) -> amerge:in13
Stream #14:0 (h264) -> scale
Stream #14:1 (aac) -> amerge:in14
Stream #15:0 (h264) -> scale
Stream #15:1 (aac) -> amerge:in15
xstack -> Stream #0:0 (libx264)
amerge -> Stream #0:1 (aac)
Press [q] to stop, [?] for help
[Parsed_amerge_17 @ 0x558494cd1180] No channel layout for input 1
[Parsed_amerge_17 @ 0x558494cd1180] Input channel layouts overlap: output layout will be determined by the number of distinct input channels
[auto_resampler_16 @ 0x558494ce5fc0] [SWR @ 0x558494e3cb40] Input channel layout '32 channels (FL+FR+FC+LFE+BL+BR+FLC+FRC+BC+SL+SR+TC+TFL+TFC+TFR+TBL+TBC+TBR+DL+DR+WL)' is not supported
[auto_resampler_16 @ 0x558494ce5fc0] Failed to configure output pad on auto_resampler_16
Error reinitializing filters!
Failed to inject frame into filter network: Invalid argument
Error while processing the decoded data for stream #15:0
Conversion failed!
使用其他选项代替该调用，例如：
[0][over] overlay=0:0[v];[0][1][2][3][4][5][6][7][8][9][10][11][12][13][14][15]amix[a]
产生：
[AVFilterGraph @ 0x55ddeb2032c0] Too many inputs specified for the "amix" filter.
Error initializing complex filters.
Invalid argument
我已经搜索了几个关于此的 SO 页面 - 许多解决方案与@llogan、@Gyan 和其他专家的问题略有不同 - 但不幸的是，none 已经奏效。
毫无疑问，解决方案非常明显，但对我来说不是！有人可以帮忙吗？如果可以的话，我将不胜感激。
改为使用 join 或 amix 过滤器
join:
ffmpeg -i a.mp4 -i b.mp4 -i c.mp4 -i d.mp4 -i e.mp4 -i f.mp4 -i g.mp4 -i h.mp4 -i i.mp4 -i j.mp4 -i k.mp4 -i l.mp4 -i m.mp4 -i n.mp4 -i o.mp4 -i q.mp4 -i p.mp4 \
-filter_complex \
"[0:v]scale=iw/4:-1[v0];[1:v]scale=iw/4:-1[v1];[2:v]scale=iw/4:-1[v2]; \
[3:v]scale=iw/4:-1[v3];[4:v]scale=iw/4:-1[v4];[5:v]scale=iw/4:-1[v5]; \
[6:v]scale=iw/4:-1[v6];[7:v]scale=iw/4:-1[v7];[8:v]scale=iw/4:-1[v8]; \
[9:v]scale=iw/4:-1[v9];[10:v]scale=iw/4:-1[v10];[11:v]scale=iw/4:-1[v11]; \
[12:v]scale=iw/4:-1[v12];[13:v]scale=iw/4:-1[v13];[14:v]scale=iw/4:-1[v14]; \
[15:v]scale=iw/4:-1[v15]; \
[v0][v1][v2][v3][v4][v5][v6][v7][v8][v9][v10][v11][v12][v13][v14][v15]xstack=inputs=16:layout=0_0|w0_0|w0+w1_0|w0+w1+w2_0|0_h0|w4_h0|w4+w5_h0|w4+w5+w6_h0|0_h0+h4|w8_h0+h4|w8+w9_h0+h4|w8+w9+w10_h0+h4|0_h0+h4+h8|w12_h0+h4+h8|w12+w13_h0+h4+h8|w12+w13+w14_h0+h4+h8; \
[0:a][1:a][2:a][3:a][4:a][5:a][6:a][7:a][8:a][9:a][10:a][11:a][12:a][13:a][14:a][15:a]join=inputs=16" \
output.mp4
amix:
amix默认为inputs=2，所以加inputs=16.
ffmpeg -i a.mp4 -i b.mp4 -i c.mp4 -i d.mp4 -i e.mp4 -i f.mp4 -i g.mp4 -i h.mp4 -i i.mp4 -i j.mp4 -i k.mp4 -i l.mp4 -i m.mp4 -i n.mp4 -i o.mp4 -i q.mp4 -i p.mp4 \
-filter_complex \
"[0:v]scale=iw/4:-1[v0];[1:v]scale=iw/4:-1[v1];[2:v]scale=iw/4:-1[v2]; \
[3:v]scale=iw/4:-1[v3];[4:v]scale=iw/4:-1[v4];[5:v]scale=iw/4:-1[v5]; \
[6:v]scale=iw/4:-1[v6];[7:v]scale=iw/4:-1[v7];[8:v]scale=iw/4:-1[v8]; \
[9:v]scale=iw/4:-1[v9];[10:v]scale=iw/4:-1[v10];[11:v]scale=iw/4:-1[v11]; \
[12:v]scale=iw/4:-1[v12];[13:v]scale=iw/4:-1[v13];[14:v]scale=iw/4:-1[v14]; \
[15:v]scale=iw/4:-1[v15]; \
[v0][v1][v2][v3][v4][v5][v6][v7][v8][v9][v10][v11][v12][v13][v14][v15]xstack=inputs=16:layout=0_0|w0_0|w0+w1_0|w0+w1+w2_0|0_h0|w4_h0|w4+w5_h0|w4+w5+w6_h0|0_h0+h4|w8_h0+h4|w8+w9_h0+h4|w8+w9+w10_h0+h4|0_h0+h4+h8|w12_h0+h4+h8|w12+w13_h0+h4+h8|w12+w13+w14_h0+h4+h8; \
[0:a][1:a][2:a][3:a][4:a][5:a][6:a][7:a][8:a][9:a][10:a][11:a][12:a][13:a][14:a][15:a]amix=inputs=16" \
output.mp4
感谢@llogan 对我的 post here 的回复，我已经能够将 16 个不同的视频合并到一部 4x4 .mp4 电影中。
不幸的是，我还希望从这 16 个剪辑 中添加 音频 并叠加它们 。按原样使用代码，它从调用中声明的第一个剪辑中获取音频。
我试过了：
ffmpeg -i a.mp4 -i b.mp4 -i c.mp4 -i d.mp4 -i e.mp4 -i f.mp4 -i g.mp4 -i h.mp4 -i i.mp4 -i j.mp4 -i k.mp4 -i l.mp4 -i m.mp4 -i n.mp4 -i o.mp4 -i q.mp4 -i p.mp4 \
-filter_complex \
"[0:v]scale=iw/4:-1[v0];[1:v]scale=iw/4:-1[v1];[2:v]scale=iw/4:-1[v2]; \
[3:v]scale=iw/4:-1[v3];[4:v]scale=iw/4:-1[v4];[5:v]scale=iw/4:-1[v5]; \
[6:v]scale=iw/4:-1[v6];[7:v]scale=iw/4:-1[v7];[8:v]scale=iw/4:-1[v8]; \
[9:v]scale=iw/4:-1[v9];[10:v]scale=iw/4:-1[v10];[11:v]scale=iw/4:-1[v11]; \
[12:v]scale=iw/4:-1[v12];[13:v]scale=iw/4:-1[v13];[14:v]scale=iw/4:-1[v14]; \
[15:v]scale=iw/4:-1[v15]; \
[v0][v1][v2][v3][v4][v5][v6][v7][v8][v9][v10][v11][v12][v13][v14]
[v15]xstack=inputs=16:layout=0_0|w0_0|w0+w1_0|w0+w1+w2_0|0_h0|w4_h0|w4+w5_h0|w4+w5+w6_h0|0_h0+h4|w8_h0+h4|w8+w9_h0+h4|w8+w9+w10_h0+h4|0_h0+h4+h8|w12_h0+h4+h8|w12+w13_h0+h4+h8|w12+w13+w14_h0+h4+h8; \
[0:a][1:a][2:a][3:a][4:a][5:a][6:a][7:a][8:a][9:a][10:a][11:a][12:a][13:a][14:a][15:a]amerge=inputs=16[a]" \
-map "[a]" -ac 2 \
output.mp4
同时合并倒数第三行作为合并音频输入的尝试，但它产生：
ffmpeg version 4.3.2-0+deb11u1ubuntu1 Copyright (c) 2000-2021 the FFmpeg developers
built with gcc 10 (Ubuntu 10.2.1-20ubuntu1)
configuration: --prefix=/usr --extra-version=0+deb11u1ubuntu1 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --arch=amd64 --enable-gpl --disable-stripping --enable-avresample --disable-filter=resample --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libdav1d --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librabbitmq --enable-librsvg --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-sdl2 --enable-pocketsphinx --enable-libmfx --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-nvenc --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared
WARNING: library configuration mismatch
avcodec configuration: --prefix=/usr --extra-version=0+deb11u1ubuntu1 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --arch=amd64 --enable-gpl --disable-stripping --enable-avresample --disable-filter=resample --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libdav1d --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librabbitmq --enable-librsvg --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-sdl2 --enable-pocketsphinx --enable-libmfx --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-nvenc --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared --enable-version3 --disable-doc --disable-programs --enable-libaribb24 --enable-liblensfun --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libtesseract --enable-libvo_amrwbenc
libavutil 56. 51.100 / 56. 51.100
libavcodec 58. 91.100 / 58. 91.100
libavformat 58. 45.100 / 58. 45.100
libavdevice 58. 10.100 / 58. 10.100
libavfilter 7. 85.100 / 7. 85.100
libavresample 4. 0. 0 / 4. 0. 0
libswscale 5. 7.100 / 5. 7.100
libswresample 3. 7.100 / 3. 7.100
libpostproc 55. 7.100 / 55. 7.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'ang.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:10.00, start: 0.000000, bitrate: 480 kb/s
Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 271 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 194 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #1, mov,mp4,m4a,3gp,3g2,mj2, from 'atv.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:17.00, start: 0.000000, bitrate: 259 kb/s
Stream #1:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 53 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #1:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 193 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #2, mov,mp4,m4a,3gp,3g2,mj2, from 'bor.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:09.00, start: 0.000000, bitrate: 255 kb/s
Stream #2:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 48 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #2:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 192 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #3, mov,mp4,m4a,3gp,3g2,mj2, from 'cen.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:07.00, start: 0.000000, bitrate: 461 kb/s
Stream #3:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 250 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #3:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 196 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #4, mov,mp4,m4a,3gp,3g2,mj2, from 'cha.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:05.00, start: 0.000000, bitrate: 267 kb/s
Stream #4:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 59 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #4:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 194 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #5, mov,mp4,m4a,3gp,3g2,mj2, from 'grd.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:07.00, start: 0.000000, bitrate: 235 kb/s
Stream #5:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 28 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #5:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 193 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #6, mov,mp4,m4a,3gp,3g2,mj2, from 'grm.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:09.00, start: 0.000000, bitrate: 294 kb/s
Stream #6:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 86 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #6:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 195 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #7, mov,mp4,m4a,3gp,3g2,mj2, from 'htv.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:12.01, start: 0.000000, bitrate: 238 kb/s
Stream #7:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 29 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #7:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 196 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #8, mov,mp4,m4a,3gp,3g2,mj2, from 'lwt.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:10.00, start: 0.000000, bitrate: 239 kb/s
Stream #8:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 30 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #8:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 195 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #9, mov,mp4,m4a,3gp,3g2,mj2, from 'sou.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:08.00, start: 0.000000, bitrate: 247 kb/s
Stream #9:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 39 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #9:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 194 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #10, mov,mp4,m4a,3gp,3g2,mj2, from 'stv.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:09.00, start: 0.000000, bitrate: 257 kb/s
Stream #10:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 51 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #10:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 192 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #11, mov,mp4,m4a,3gp,3g2,mj2, from 'tha.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:06.00, start: 0.000000, bitrate: 454 kb/s
Stream #11:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 245 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #11:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 194 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #12, mov,mp4,m4a,3gp,3g2,mj2, from 'ttt.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:10.01, start: 0.000000, bitrate: 258 kb/s
Stream #12:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 51 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #12:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 193 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #13, mov,mp4,m4a,3gp,3g2,mj2, from 'utv.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:08.00, start: 0.000000, bitrate: 443 kb/s
Stream #13:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 234 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #13:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 194 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #14, mov,mp4,m4a,3gp,3g2,mj2, from 'wtv.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:08.00, start: 0.000000, bitrate: 431 kb/s
Stream #14:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 224 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #14:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 194 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #15, mov,mp4,m4a,3gp,3g2,mj2, from 'ytv.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:08.00, start: 0.000000, bitrate: 332 kb/s
Stream #15:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 123 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #15:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 195 kb/s (default)
Metadata:
handler_name : SoundHandler
File 'output.mp4' already exists. Overwrite? [y/N] y
Stream mapping:
Stream #0:0 (h264) -> scale
Stream #0:1 (aac) -> amerge:in0
Stream #1:0 (h264) -> scale
Stream #1:1 (aac) -> amerge:in1
Stream #2:0 (h264) -> scale
Stream #2:1 (aac) -> amerge:in2
Stream #3:0 (h264) -> scale
Stream #3:1 (aac) -> amerge:in3
Stream #4:0 (h264) -> scale
Stream #4:1 (aac) -> amerge:in4
Stream #5:0 (h264) -> scale
Stream #5:1 (aac) -> amerge:in5
Stream #6:0 (h264) -> scale
Stream #6:1 (aac) -> amerge:in6
Stream #7:0 (h264) -> scale
Stream #7:1 (aac) -> amerge:in7
Stream #8:0 (h264) -> scale
Stream #8:1 (aac) -> amerge:in8
Stream #9:0 (h264) -> scale
Stream #9:1 (aac) -> amerge:in9
Stream #10:0 (h264) -> scale
Stream #10:1 (aac) -> amerge:in10
Stream #11:0 (h264) -> scale
Stream #11:1 (aac) -> amerge:in11
Stream #12:0 (h264) -> scale
Stream #12:1 (aac) -> amerge:in12
Stream #13:0 (h264) -> scale
Stream #13:1 (aac) -> amerge:in13
Stream #14:0 (h264) -> scale
Stream #14:1 (aac) -> amerge:in14
Stream #15:0 (h264) -> scale
Stream #15:1 (aac) -> amerge:in15
xstack -> Stream #0:0 (libx264)
amerge -> Stream #0:1 (aac)
Press [q] to stop, [?] for help
[Parsed_amerge_17 @ 0x558494cd1180] No channel layout for input 1
[Parsed_amerge_17 @ 0x558494cd1180] Input channel layouts overlap: output layout will be determined by the number of distinct input channels
[auto_resampler_16 @ 0x558494ce5fc0] [SWR @ 0x558494e3cb40] Input channel layout '32 channels (FL+FR+FC+LFE+BL+BR+FLC+FRC+BC+SL+SR+TC+TFL+TFC+TFR+TBL+TBC+TBR+DL+DR+WL)' is not supported
[auto_resampler_16 @ 0x558494ce5fc0] Failed to configure output pad on auto_resampler_16
Error reinitializing filters!
Failed to inject frame into filter network: Invalid argument
Error while processing the decoded data for stream #15:0
Conversion failed!
使用其他选项代替该调用，例如：
[0][over] overlay=0:0[v];[0][1][2][3][4][5][6][7][8][9][10][11][12][13][14][15]amix[a]
产生：
[AVFilterGraph @ 0x55ddeb2032c0] Too many inputs specified for the "amix" filter.
Error initializing complex filters.
Invalid argument
我已经搜索了几个关于此的 SO 页面 - 许多解决方案与@llogan、@Gyan 和其他专家的问题略有不同 - 但不幸的是，none 已经奏效。
毫无疑问，解决方案非常明显，但对我来说不是！有人可以帮忙吗？如果可以的话，我将不胜感激。
改为使用 join 或 amix 过滤器
join:
ffmpeg -i a.mp4 -i b.mp4 -i c.mp4 -i d.mp4 -i e.mp4 -i f.mp4 -i g.mp4 -i h.mp4 -i i.mp4 -i j.mp4 -i k.mp4 -i l.mp4 -i m.mp4 -i n.mp4 -i o.mp4 -i q.mp4 -i p.mp4 \
-filter_complex \
"[0:v]scale=iw/4:-1[v0];[1:v]scale=iw/4:-1[v1];[2:v]scale=iw/4:-1[v2]; \
[3:v]scale=iw/4:-1[v3];[4:v]scale=iw/4:-1[v4];[5:v]scale=iw/4:-1[v5]; \
[6:v]scale=iw/4:-1[v6];[7:v]scale=iw/4:-1[v7];[8:v]scale=iw/4:-1[v8]; \
[9:v]scale=iw/4:-1[v9];[10:v]scale=iw/4:-1[v10];[11:v]scale=iw/4:-1[v11]; \
[12:v]scale=iw/4:-1[v12];[13:v]scale=iw/4:-1[v13];[14:v]scale=iw/4:-1[v14]; \
[15:v]scale=iw/4:-1[v15]; \
[v0][v1][v2][v3][v4][v5][v6][v7][v8][v9][v10][v11][v12][v13][v14][v15]xstack=inputs=16:layout=0_0|w0_0|w0+w1_0|w0+w1+w2_0|0_h0|w4_h0|w4+w5_h0|w4+w5+w6_h0|0_h0+h4|w8_h0+h4|w8+w9_h0+h4|w8+w9+w10_h0+h4|0_h0+h4+h8|w12_h0+h4+h8|w12+w13_h0+h4+h8|w12+w13+w14_h0+h4+h8; \
[0:a][1:a][2:a][3:a][4:a][5:a][6:a][7:a][8:a][9:a][10:a][11:a][12:a][13:a][14:a][15:a]join=inputs=16" \
output.mp4
amix:
amix默认为inputs=2，所以加inputs=16.
ffmpeg -i a.mp4 -i b.mp4 -i c.mp4 -i d.mp4 -i e.mp4 -i f.mp4 -i g.mp4 -i h.mp4 -i i.mp4 -i j.mp4 -i k.mp4 -i l.mp4 -i m.mp4 -i n.mp4 -i o.mp4 -i q.mp4 -i p.mp4 \
-filter_complex \
"[0:v]scale=iw/4:-1[v0];[1:v]scale=iw/4:-1[v1];[2:v]scale=iw/4:-1[v2]; \
[3:v]scale=iw/4:-1[v3];[4:v]scale=iw/4:-1[v4];[5:v]scale=iw/4:-1[v5]; \
[6:v]scale=iw/4:-1[v6];[7:v]scale=iw/4:-1[v7];[8:v]scale=iw/4:-1[v8]; \
[9:v]scale=iw/4:-1[v9];[10:v]scale=iw/4:-1[v10];[11:v]scale=iw/4:-1[v11]; \
[12:v]scale=iw/4:-1[v12];[13:v]scale=iw/4:-1[v13];[14:v]scale=iw/4:-1[v14]; \
[15:v]scale=iw/4:-1[v15]; \
[v0][v1][v2][v3][v4][v5][v6][v7][v8][v9][v10][v11][v12][v13][v14][v15]xstack=inputs=16:layout=0_0|w0_0|w0+w1_0|w0+w1+w2_0|0_h0|w4_h0|w4+w5_h0|w4+w5+w6_h0|0_h0+h4|w8_h0+h4|w8+w9_h0+h4|w8+w9+w10_h0+h4|0_h0+h4+h8|w12_h0+h4+h8|w12+w13_h0+h4+h8|w12+w13+w14_h0+h4+h8; \
[0:a][1:a][2:a][3:a][4:a][5:a][6:a][7:a][8:a][9:a][10:a][11:a][12:a][13:a][14:a][15:a]amix=inputs=16" \
output.mp4