On Thu, Nov 23, 2017 at 13:16:27 +0100, Carles Vila wrote: > Could you please have a look at what I'm doing wrong? > Specifically I'm not sure what the [0:1] before the pan does, but it seems > to be necessary.
[0:1] is the input stream mapping to the complex filter chain. With this syntax, it references the second stream from the first file. For your particular file, it's indeed the audio stream. You could use "[0:a]", just in case the order of video and audio streams are swapped (or undetermined, as in VOBs). > Carles$ ffmpeg -i MEAT01_01A_ENG_ME_DV_5.1_24HD_TC.mov -filter_complex > "[0:1]pan=2c|c0=c0+c1|c1=c2+c3" -s 640x360 -pix_fmt yuv420p proxy_stereo.mp4 While this result looks okay: > Stream mapping: > Stream #0:1 (pcm_s24le) -> pan (graph 0) > pan (graph 0) -> Stream #0:0 (aac) > Stream #0:0 -> #0:1 (prores (native) -> h264 (libx264)) please do try changing that command line to the more specific mapping variant: $ ffmpeg -i MEAT01_01A_ENG_ME_DV_5.1_24HD_TC.mov -filter_complex "[0:a]pan=2c|c0=c0+c1|c1=c2+c3[a]" -s 640x360 -pix_fmt yuv420p -map 0:v -map "[a]" proxy_stereo.mp4 Additionally, if you increase the logging level with "loglevel verbose", the pan filter should show you what it's doing. If that command still doesn't work, can you change the filter expression to "[0:a]pan=2c|c0=c0+c1|c1=c2+c3[a],volumedetect" so that we can get an impression whether something should be heard? > ffmpeg version 3.1.4 Copyright (c) 2000-2016 the FFmpeg developers This is a bit old. Could you kindly test a recent build from git master, or a recent release? We don't want to help you debug long-solved bugs, if you know what I mean. (If you can't build yourself, binaries are available for many major platforms.) > Input #0, mov,mp4,m4a,3gp,3g2,mj2, from > 'MEAT01_01A_ENG_ME_DV_5.1_24HD_TC.mov': > Metadata: > major_brand : qt > minor_version : 537199360 > compatible_brands: qt > creation_time : 2017-11-09 12:37:45 > Duration: 00:11:13.59, start: 0.000000, bitrate: 178829 kb/s > Stream #0:0(eng): Video: prores (apch / 0x68637061), yuv422p10le(bt709), > 1920x1080, 164992 kb/s, SAR 1:1 DAR 16:9, 23.98 fps, 23.98 tbr, 24k tbn, 24k > tbc (default) [...] > Output #0, mp4, to 'proxy_stereo.mp4': [...] > Stream #0:1(eng): Video: h264 (libx264) ([33][0][0][0] / 0x0021), > yuv420p, 640x360 [SAR 1:1 DAR 16:9], q=-1--1, 0.04 fps, 24k tbn, 23.98 tbc > (default) Wow, why would ffmpeg output a 23.98 fps video as 0.04 fps? (Unrelated.) Moritz _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
