I'm now looking to expand the 4x4 code very helpfully provided by @llogan yesterday into one taking 25 different and equally-scaled audio and video inputs to make a 5x5 grid (at which point, I'll stop):
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 p.mp4 -i q.mp4 -i r.mp4 -i s.mp4 -i t.mp4 -i u.mp4 -i v.mp4 -i w.mp4 -i x.mp4 -i y.mp4 \
-filter_complex \
"[0:v]scale=iw/5:-1[v0];[1:v]scale=iw/5:-1[v1];[2:v]scale=iw/5:-1[v2]; \
[3:v]scale=iw/5:-1[v3];[4:v]scale=iw/5:-1[v4];[5:v]scale=iw/5:-1[v5]; \
[6:v]scale=iw/5:-1[v6];[7:v]scale=iw/5:-1[v7];[8:v]scale=iw/5:-1[v8]; \
[9:v]scale=iw/5:-1[v9];[10:v]scale=iw/5:-1[v10];[11:v]scale=iw/5:-1[v11]; \
[12:v]scale=iw/5:-1[v12];[13:v]scale=iw/5:-1[v13];[14:v]scale=iw/5:-1[v14]; \
[15:v]scale=iw/5:-1[v15];[16:v]scale=iw/5:-1[v16];[17:v]scale=iw/5:-1[v17]; \
[18:v]scale=iw/5:-1[v18];[19:v]scale=iw/5:-1[v19];[20:v]scale=iw/5:-1[v20]; \
[21:v]scale=iw/5:-1[v21];[22:v]scale=iw/5:-1[v22];[23:v]scale=iw/5:-1[v23]; \
[24:v]scale=iw/5:-1[v24]; \
[v0][v1][v2][v3][v4][v5][v6][v7][v8][v9][v10][v11][v12][v13][v14][v15][v16][v17][v18][v19][v20][v21][v22][v23][v24]xstack=inputs=25:layout=0_0|0_h0|0_h0+h1|0_h0+h1+h2|0_h0+h1+h2+h3|w0_0|w0_h0|w0_h0+h1|w0_h0+h1+h2|w0_h0+h1+h2+h3|w0+w4_0|w0+w4_h0|w0+w4_h0+h1|w0+w4_h0+h1+h2|w0+w4_h0+h1+h2+h3|w0+w4+w8_0|w0+w4+w8_h0|w0+w4+w8_h0+h1|w0+w4+w8_h0+h1+h2|w0+w4+w8_h0+h1+h2+h3|w0+w4+w8+w12_0|w0+w4+w8+w12_h0|w0+w4+w8+w12_h0+h1|w0+w4+w8+w12_h0+h1+h2|w0+w4+w8+w12_h0+h1+h2+h3; \
[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][16:a][17:a][18:a][19:a][20:a][21:a][22:a][23:a][24:a]amix=inputs=25" \
output.mp4
Unfortunately, this produces errors:
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 'abc.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:08.00, start: 0.000000, bitrate: 248 kb/s
Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 41 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, 193 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #1, 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 #1:0(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 #1:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 194 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #2, mov,mp4,m4a,3gp,3g2,mj2, from 'ard.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:09.00, start: 0.000000, bitrate: 256 kb/s
Stream #2:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 49 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, 193 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #3, 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 #3:0(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 #3:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 193 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #4, 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 #4:0(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 #4:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 192 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #5, 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 #5:0(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 #5:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 196 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #6, 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 #6:0(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 #6:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 194 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #7, mov,mp4,m4a,3gp,3g2,mj2, from 'grad.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:05.01, start: 0.000000, bitrate: 246 kb/s
Stream #7:0(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 #7:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 192 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #8, mov,mp4,m4a,3gp,3g2,mj2, from 'gram.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 #8:0(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 #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 '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 #9:0(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 #9:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 196 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #10, mov,mp4,m4a,3gp,3g2,mj2, from 'its1.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:07.00, start: 0.000000, bitrate: 238 kb/s
Stream #10:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 31 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 'its2.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:08.00, start: 0.000000, bitrate: 241 kb/s
Stream #11:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 34 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, 192 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #12, 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 #12:0(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 #12:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 195 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #13, 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 #13:0(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 #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 '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 #14:0(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 #14:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 192 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #15, 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 #15:0(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 #15:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 194 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #16, mov,mp4,m4a,3gp,3g2,mj2, from 'tlc.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:09.00, start: 0.000000, bitrate: 275 kb/s
Stream #16:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 67 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #16:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 194 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #17, mov,mp4,m4a,3gp,3g2,mj2, from 'tsw.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:11.00, start: 0.000000, bitrate: 457 kb/s
Stream #17:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 251 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #17:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 192 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #18, 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 #18:0(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 #18:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 193 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #19, mov,mp4,m4a,3gp,3g2,mj2, from 'tvam.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf57.82.100
Duration: 00:00:11.31, start: 0.000000, bitrate: 383 kb/s
Stream #19:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 352x288 [SAR 178:163 DAR 1958:1467], 251 kb/s, 25 fps, 25 tbr, 12800 tbn, 50 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #19:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 125 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #20, mov,mp4,m4a,3gp,3g2,mj2, from 'tvs.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:10.01, start: 0.000000, bitrate: 252 kb/s
Stream #20:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 44 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #20:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 194 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #21, mov,mp4,m4a,3gp,3g2,mj2, from 'tww.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:09.00, start: 0.000000, bitrate: 277 kb/s
Stream #21:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360, 69 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #21:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 194 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #22, 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 #22:0(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 #22:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 194 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #23, 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 #23:0(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 #23:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 194 kb/s (default)
Metadata:
handler_name : SoundHandler
Input #24, 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 #24:0(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 #24:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 195 kb/s (default)
Metadata:
handler_name : SoundHandler
[AVFilterGraph @ 0x55ad3b4d4a00] No such filter: ' '
Error initializing complex filters.
Invalid argument
The layout code has now become extremely complex, but I've carefully followed the 4x4 example as given in the manual here and I don't think I'm doing much wrong. Breaking down and reordering the layout code I used above looks like this:
input1(0, 0) | input6 (w0, 0) | input11(w0+w4, 0) | input16(w0+w4+w8, 0) | input21(w0+w4+w8+w12, 0)
input2(0, h0) | input7 (w0, h0) | input12(w0+w4, h0) | input17(w0+w4+w8, h0) | input22(w0+w4+w8+w12, h0)
input3(0, h0+h1) | input8 (w0, h0+h1) | input13(w0+w4, h0+h1) | input18(w0+w4+w8, h0+h1) | input23(w0+w4+w8+w12, h0+h1)
input4(0, h0+h1+h2) | input9 (w0, h0+h1+h2) | input14(w0+w4, h0+h1+h2) | input19(w0+w4+w8, h0+h1+h2) | input24(w0+w4+w8+w12, h0+h1+h2)
input5(0, h0+h1+h2+h3)| input10(w0, h0+h1+h2+h3) | input15(w0+w4, h0+h1+h2+h3)| input20(w0+w4+w8, h0+h1+h2+h3)| input25(w0+w4+w8+w12, h0+h1+h2+h3)
To my mind, w12 and h3 would logically be the next set of width and height parameters to add on in order to make the grid expansion from 4x4 to 5x5 work. Is that what's causing the code to choke? If it's not this, it's not obvious to me what it might be, as I've checked the whole code as thoroughly as possible.
Once again, I'll be very grateful for your assistance.
Thanks very much, Clive
