在将音频编码到webm时遇到问题。尝试了许多不同的方法，它只是没有发生。每次通过前，命令都会打印在下面。
我尝试过移动音频命令，尝试不同的比特率，不同的音频命令，并在几个不同的文件上尝试过它们都有音频。
使用x264将这些文件编码到MP4会导致没有问题并且工作得很好并且播放音频，所以它似乎只是webm的一个问题。如下所示，它是一个2遍编码。
感谢您提供的任何帮助！
克雷格
Webm LG PASS 1...........................
webm_pass1: /usr/bin/ffmpeg -i /home/thedirectory/video613268.mov -codec:v libvpx -quality good -vf 'scale=640:360 [scaled];movie=/home/thedirectory/watermarks/w640X360.png [logo];[scaled][logo] overlay' -cpu-used 0 -b:v 500k -aspect 16:9 -qmin 10 -qmax 42 -maxrate:v 500k -bufsize:v 1000k -r:v 25/1 -force_fps -threads 0 -an -acodec libvorbis -ac 2 -ab 96k -ar 44100 -pass 1 -f webm -y /dev/null
ffmpeg version 0.10.2 Copyright (c) 2000-2012 the FFmpeg developers
built on Mar 11 2013 14:48:26 with gcc 4.6.2 20111027 (Red Hat 4.6.2-2)
configuration: --prefix=/usr --libdir=/usr/lib64 --shlibdir=/usr/lib64 --mandir=/usr/share/man --incdir=/usr/include --disable-avisynth --extra-cflags='-O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -m64 -mtune=generic -fPIC' --enable-avfilter --enable-libfaac --enable-libgsm --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libx264 --enable-gpl --enable-nonfree --enable-postproc --enable-pthreads --enable-shared --enable-swscale --enable-vdpau --enable-version3 --enable-x11grab --enable-libvorbis --enable-libvpx
libavutil 51. 35.100 / 51. 35.100
libavcodec 53. 61.100 / 53. 61.100
libavformat 53. 32.100 / 53. 32.100
libavdevice 53. 4.100 / 53. 4.100
libavfilter 2. 61.100 / 2. 61.100
libswscale 2. 1.100 / 2. 1.100
libswresample 0. 6.100 / 0. 6.100
libpostproc 52. 0.100 / 52. 0.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/home/thedirectory/video613268.mov':
Metadata:
major_brand : qt
minor_version : 537199360
compatible_brands: qt
creation_time : 2013-02-23 20:04:32
Duration: 00:00:21.02, start: 0.000000, bitrate: 114326 kb/s
Stream #0:0(eng): Video: mjpeg (jpeg / 0x6765706A), yuvj422p, 1920x1080 [SAR 72:72 DAR 16:9], 112786 kb/s, 29.97 fps, 29.97 tbr, 2997 tbn, 2997 tbc
Metadata:
creation_time : 2013-02-23 20:04:32
handler_name : ?Gestionnaire d?alias Apple
Stream #0:1(eng): Audio: pcm_s16be (twos / 0x736F7774), 48000 Hz, 2 channels, s16, 1536 kb/s
Metadata:
creation_time : 2013-02-23 20:04:32
handler_name : ?Gestionnaire d?alias Apple
Incompatible pixel format 'yuvj422p' for codec 'libvpx', auto-selecting format 'yuv420p'
[buffer @ 0x1f675a0] w:1920 h:1080 pixfmt:yuvj422p tb:1/1000000 sar:1/1 sws_param:
[movie @ 0x1f799c0] seek_point:0 format_name:(null) file_name:/home/thedirectory/watermarks/w640X360.png stream_index:0
[overlay @ 0x1f7c2c0] auto-inserting filter 'auto-inserted scale 0' between the filter 'Parsed_movie_1' and the filter 'Parsed_overlay_2'
[scale @ 0x1f78d40] w:1920 h:1080 fmt:yuvj422p -> w:640 h:360 fmt:yuv420p flags:0x4
[scale @ 0x1f7cde0] w:640 h:360 fmt:rgba -> w:640 h:360 fmt:yuva420p flags:0x4
[overlay @ 0x1f7c2c0] main w:640 h:360 fmt:yuv420p overlay x:0 y:0 w:640 h:360 fmt:yuva420p
[overlay @ 0x1f7c2c0] main_tb:1/1000000 overlay_tb:1/25 -> tb:1/1000000 exact:1
[libvpx @ 0x1f77ce0] v1.0.0
Output #0, webm, to '/dev/null':
Metadata:
major_brand : qt
minor_version : 537199360
compatible_brands: qt
creation_time : 2013-02-23 20:04:32
encoder : Lavf53.32.100
Stream #0:0(eng): Video: vp8, yuv420p, 640x360 [SAR 1:1 DAR 16:9], q=10-42, pass 1, 500 kb/s, 1k tbn, 25 tbc
Metadata:
creation_time : 2013-02-23 20:04:32
handler_name : ?Gestionnaire d?alias Apple
Stream mapping:
Stream #0:0 -> #0:0 (mjpeg -> libvpx)
Press [q] to stop, [?] for help
frame= 527 fps= 21 q=0.0 Lsize= 0kB time=00:00:00.00 bitrate= 0.0kbits/s dup=0 drop=103
video:0kB audio:0kB global headers:0kB muxing overhead -nan%
Output file is empty, nothing was encoded (check -ss / -t / -frames parameters if used)
Webm LG PASS 2.......................
webm_pass2: /usr/bin/ffmpeg -i /home/thedirectory/video613268.mov -codec:v libvpx -quality good -vf 'scale=640:360 [scaled];movie=/home/thedirectory/watermarks/w640X360.png [logo];[scaled][logo] overlay' -cpu-used 0 -b:v 500k -aspect 16:9 -qmin 10 -qmax 42 -maxrate:v 500k -bufsize:v 1000k -r:v 24/1 -force_fps -threads 0 -an -acodec libvorbis -ac 2 -ab 96k -ar 44100 -pass 2 -f webm -y /media/amazons3/webmlg/video613268.mov.webm
ffmpeg version 0.10.2 Copyright (c) 2000-2012 the FFmpeg developers
built on Mar 11 2013 14:48:26 with gcc 4.6.2 20111027 (Red Hat 4.6.2-2)
configuration: --prefix=/usr --libdir=/usr/lib64 --shlibdir=/usr/lib64 --mandir=/usr/share/man --incdir=/usr/include --disable-avisynth --extra-cflags='-O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -m64 -mtune=generic -fPIC' --enable-avfilter --enable-libfaac --enable-libgsm --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libx264 --enable-gpl --enable-nonfree --enable-postproc --enable-pthreads --enable-shared --enable-swscale --enable-vdpau --enable-version3 --enable-x11grab --enable-libvorbis --enable-libvpx
libavutil 51. 35.100 / 51. 35.100
libavcodec 53. 61.100 / 53. 61.100
libavformat 53. 32.100 / 53. 32.100
libavdevice 53. 4.100 / 53. 4.100
libavfilter 2. 61.100 / 2. 61.100
libswscale 2. 1.100 / 2. 1.100
libswresample 0. 6.100 / 0. 6.100
libpostproc 52. 0.100 / 52. 0.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/home/thedirectory/video613268.mov':
Metadata:
major_brand : qt
minor_version : 537199360
compatible_brands: qt
creation_time : 2013-02-23 20:04:32
Duration: 00:00:21.02, start: 0.000000, bitrate: 114326 kb/s
Stream #0:0(eng): Video: mjpeg (jpeg / 0x6765706A), yuvj422p, 1920x1080 [SAR 72:72 DAR 16:9], 112786 kb/s, 29.97 fps, 29.97 tbr, 2997 tbn, 2997 tbc
Metadata:
creation_time : 2013-02-23 20:04:32
handler_name : ?Gestionnaire d?alias Apple
Stream #0:1(eng): Audio: pcm_s16be (twos / 0x736F7774), 48000 Hz, 2 channels, s16, 1536 kb/s
Metadata:
creation_time : 2013-02-23 20:04:32
handler_name : ?Gestionnaire d?alias Apple
Incompatible pixel format 'yuvj422p' for codec 'libvpx', auto-selecting format 'yuv420p'
[buffer @ 0x1f2a5a0] w:1920 h:1080 pixfmt:yuvj422p tb:1/1000000 sar:1/1 sws_param:
[movie @ 0x1f3bec0] seek_point:0 format_name:(null) file_name:/home/thedirectory/watermarks/w640X360.png stream_index:0
[overlay @ 0x1f3f2c0] auto-inserting filter 'auto-inserted scale 0' between the filter 'Parsed_movie_1' and the filter 'Parsed_overlay_2'
[scale @ 0x1f3c8a0] w:1920 h:1080 fmt:yuvj422p -> w:640 h:360 fmt:yuv420p flags:0x4
[scale @ 0x1f3fde0] w:640 h:360 fmt:rgba -> w:640 h:360 fmt:yuva420p flags:0x4
[overlay @ 0x1f3f2c0] main w:640 h:360 fmt:yuv420p overlay x:0 y:0 w:640 h:360 fmt:yuva420p
[overlay @ 0x1f3f2c0] main_tb:1/1000000 overlay_tb:1/25 -> tb:1/1000000 exact:1
[libvpx @ 0x1f3ace0] v1.0.0
Output #0, webm, to '/media/amazons3/webmlg/video613268.mov.webm':
Metadata:
major_brand : qt
minor_version : 537199360
compatible_brands: qt
creation_time : 2013-02-23 20:04:32
encoder : Lavf53.32.100
Stream #0:0(eng): Video: vp8, yuv420p, 640x360 [SAR 1:1 DAR 16:9], q=10-42, pass 2, 500 kb/s, 1k tbn, 24 tbc
Metadata:
creation_time : 2013-02-23 20:04:32
handler_name : ?Gestionnaire d?alias Apple
Stream mapping:
Stream #0:0 -> #0:0 (mjpeg -> libvpx)
Press [q] to stop, [?] for help
frame= 506 fps= 7 q=0.0 Lsize= 1610kB time=00:00:21.08 bitrate= 625.8kbits/s dup=0 drop=124
video:1389kB audio:0kB global headers:0kB muxing overhead 15.952140%