Hi,
We have developed a video conference application with Licode and we have
now a problem. We record the streams but we would like to see them
instantly when they finished being recorded without transcoding or
postprocessing them. For that we use simple HTML5 video tag but the mkv
files that Licode makes don’t work (HTML5 video element fires onerror event
with code 3 (error decoding)).
Then we transcode with ffmpeg one of these videos and we realised that this
new video works (id plays fine). We use:
ffmpeg -i video.mkv -s 640x480 -vcodec vp8 -acodec pcm_mulaw -c:a copy
result.mkv
If i’m not wrong, Licode records in VP8 and pcmu too, so both videos use
same codecs, we used ffmpeg -i on both files and we get:
For Licode’s one:
libavutil 52. 38.100 / 52. 38.100
libavcodec 55. 18.102 / 55. 18.102
libavformat 55. 12.100 / 55. 12.100
libavdevice 55. 3.100 / 55. 3.100
libavfilter 3. 79.101 / 3. 79.101
libswscale 2. 3.100 / 2. 3.100
libswresample 0. 17.102 / 0. 17.102
libpostproc 52. 3.100 / 52. 3.100
Guessed Channel Layout for Input Stream #0.1 : mono
Input #0, matroska,webm, from ‘video.mkv’:
Metadata:
ENCODER : Lavf54.20.4
Duration: 00:00:10.59, start: 0.000000, bitrate: 358 kb/s
Stream #0:0: Video: vp8, yuv420p, 640x480, SAR 1:1 DAR 4:3, 30 fps, 30
tbr, 1k tbn, 1k tbc (default)
Stream #0:1: Audio: pcm_mulaw ([7][0][0][0] / 0x0007), 8000 Hz, mono,
s16, 64 kb/s (default)
For transcoded video:
libavutil 52. 38.100 / 52. 38.100
libavcodec 55. 18.102 / 55. 18.102
libavformat 55. 12.100 / 55. 12.100
libavdevice 55. 3.100 / 55. 3.100
libavfilter 3. 79.101 / 3. 79.101
libswscale 2. 3.100 / 2. 3.100
libswresample 0. 17.102 / 0. 17.102
libpostproc 52. 3.100 / 52. 3.100
Guessed Channel Layout for Input Stream #0.1 : mono
Input #0, matroska,webm, from ‘result.mkv’:
Metadata:
ENCODER : Lavf55.12.100
Duration: 00:00:06.07, start: 0.000000, bitrate: 358kb/s
Stream #0:0: Video: vp8, yuv420p, 640x480, SAR 1:1 DAR 4:3, 30 fps, 30
tbr, 1k tbn, 1k tbc (default)
Stream #0:1: Audio: pcm_mulaw ([7][0][0][0] / 0x0007), 8000 Hz, mono,
s16, 64 kb/s (default)
They only differ in the encoder. So can we achieve the second file while
recording without postprocess it? Or can we use another codec which get
played well in HTML video elements?
Thank you.
Sergio.