/usr/bin/ffmpeg -i '+file+' -c:v libwebp -vsync vfr -vf "select=isnan(prev_selected_t)+gte(t-prev_selected_t\,10),scale=-1:100,tile=5x5" c_thumb%01d.webp
无法创建带有 5x5 缩略图的图像，可能是什么问题？
ffmpeg version N-100470-g5b48d2a Copyright (c) 2000-2020 the FFmpeg developers
built with gcc 4.8.5 (GCC) 20150623 (Red Hat 4.8.5-44)
configuration: --prefix=/root/ffmpeg_build --pkg-config-flags=--static --extra-cflags=-I/root/ffmpeg_build/include --extra-ldflags=-L/root/ffmpeg_build/lib --extra-libs=-lpthread --extra-libs=-lm --bindir=/root/bin --enable-gpl --enable-libfdk_aac --enable-libfreetype --enable-libvpx --enable-libx264 --enable-nonfree --enable-libvorbis --enable-libwebp --enable-pic --enable-ffplay --enable-fontconfig --enable-frei0r --enable-gpl --enable-version3 --enable-libass --enable-libfribidi --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libopus --enable-libspeex --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxvid --enable-libzimg --enable-nonfree --enable-openssl --enable-libx265 --enable-libwebp
libavutil 56. 62.100 / 56. 62.100
libavcodec 58.115.102 / 58.115.102
libavformat 58. 65.100 / 58. 65.100
libavdevice 58. 11.103 / 58. 11.103
libavfilter 7. 94.100 / 7. 94.100
libswscale 5. 8.100 / 5. 8.100
libswresample 3. 8.100 / 3. 8.100
libpostproc 55. 8.100 / 55. 8.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/2179.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.12.100
Duration: 00:38:58.46, start: 0.000000, bitrate: 356 kb/s
Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], 157 kb/s, 10 fps, 10 tbr, 10240 tbn, 20 tbc (default)
Metadata:
handler_name : VideoHandler
vendor_id : [0][0][0][0]
Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 196 kb/s (default)
Metadata:
handler_name : SoundHandler
vendor_id : [0][0][0][0]
Stream mapping:
Stream #0:0 -> #0:0 (h264 (native) -> webp (libwebp))
Press [q] to stop, [?] for help
Output #0, image2, to '/c_thumb%01d.webp':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.65.100
Stream #0:0(und): Video: webp, yuv420p(tv, progressive), 890x500 [SAR 800:801 DAR 16:9], q=2-31, 200 kb/s, 0.40 fps, 0.40 tbn (default)
Metadata:
handler_name : VideoHandler
vendor_id : [0][0][0][0]
encoder : Lavc58.115.102 libwebp
ffmpeg: symbol lookup error: ffmpeg: undefined symbol: WebPMemoryWriterClear