vp9

问题 I am not able to connect a call from Firefox to Firefox using VP9, allthough I have tried modifying the SDP in several different ways. I have a site similar to https://webrtc.github.io/samples/src/content/peerconnection/munge-sdp/, where I simply remove the unwanted codec. In Firefox, VP9 is not listed when I initiate the call. I have enabled VP9 on both sender and receiver, by setting media.mediasource.webm.enabled to true in about:config . Does anybody know how to modify it correctly to get

问题 I am using ffmpeg 2.8 on OSX. I try to convert a short mp4 video to webm for adaptive streaming like suggested here http://wiki.webmproject.org/adaptive-streaming/instructions-to-playback-adaptive-webm-using-dash like this: VP9_DASH_PARAMS="-tile-columns 6 -frame-parallel 1" ffmpeg -i t2.mp4 -c:v libvpx-vp9 -s 160x90 -b:v 250k -keyint_min 150 -g 150 ${VP9_DASH_PARAMS} -an -f webm -dash 1 video_160x90_250k.webm ffmpeg -i t2.mp4 -c:a libvorbis -b:a 128k -vn -f webm -dash 1 audio_128k.webm

问题 I am simply trying to convert a vp9 webm I have into a vp8 webm. this is the command I'm using. ffmpeg -i in.webm -c:v vp8 out.webm the vp8 encoder returns a strange error Input #0, matroska,webm, from 'in.webm': Metadata: encoder : google Duration: 00:02:34.60, start: 0.000000, bitrate: 404 kb/s Stream #0:0(eng): Video: vp9 (Profile 0), yuv420p(tv, bt709/unknown/unknown), 640x360, SAR 1:1 DAR 16:9, 30 fps, 30 tbr, 1k tbn, 1k tbc (default) Stream mapping: Stream #0:0 -> #0:0 (vp9 (native) ->

问题 I am simply trying to convert a vp9 webm I have into a vp8 webm. this is the command I'm using. ffmpeg -i in.webm -c:v vp8 out.webm the vp8 encoder returns a strange error Input #0, matroska,webm, from 'in.webm': Metadata: encoder : google Duration: 00:02:34.60, start: 0.000000, bitrate: 404 kb/s Stream #0:0(eng): Video: vp9 (Profile 0), yuv420p(tv, bt709/unknown/unknown), 640x360, SAR 1:1 DAR 16:9, 30 fps, 30 tbr, 1k tbn, 1k tbc (default) Stream mapping: Stream #0:0 -> #0:0 (vp9 (native) ->