Transcode url / ffmpeg

[bgowland]

sub - I know you don't recommend using the /transcode url but can you explain some logic of how the ffmpeg command line args are formatted in config.xml (and how they're processed)?

This is from a web.log posted by xsirxx in this post...

http://forums.nextpvr.com/showthread.php...post464240

Code:

2013-10-03 00:10:01.818    [DEBUG][4]    Got Web Request (192.168.0.13): /transcode    channel=10&client=4c075158-b5e2-4313-8332-d3d4949094d7&resolution=768x432&bitrate=1600k
2013-10-03 00:10:02.005    [DEBUG][4]    Running: C:\Program Files (x86)\NPVR\other\ffmpeg.exe -y -v 0 -i http://127.0.0.1:8866/live?channel=10 -f mpegts -acodec libfaac -ar 48000 -ac 2 -ab 64k -s 1280x720 -vcodec libx264 -b 1600k -flags +loop -cmp +chroma -refs 1 -coder 0 -me_range 16 -keyint_min 25 -sc_threshold 40 -i_qfactor 0.71 -bt 200k -maxrate 96k -bufsize 96k -rc_eq 'blurCplx^(1-qComp)' -qcomp 0.6 -qmin 10 -qmax 51 -qdiff 4 -level 30 -aspect 768:432 -g 30 -async 2  C:\Temp\live-tWTTE-DT-2736-1.ts

The config.xml <TranscodeArgs> has "-s [RESOLUTION] " which is logged here as 1280x768 so suggests you've pre-processed the stream (to find the input resolution) or simply have this as a default when running ffmpeg.

EDIT: OK, ignore the above as it appears he had edited the TranscodeArgs to replace [RESOLUTION] with fixed values.

Also as you can see from the url it's requesting "&resolution=768x432" but you're passing this to ffmpeg as the "-aspect" parameter. Admittedly those figures boil down to a 16:9 aspect ratio but I would have thought the "&resolution" request should be used for the WxH of the transcoded file.

Also is there a particular reason to use libx264 for -vcodec and libfaac for -acodec and enforce a .ts file extension for the output file?

Cheers,
Brian

[mvallevand]

Also is there a particular reason to use libx264 for -vcodec and libfaac for -acodec and enforce a .ts file extension for the output file?

That's easy (although libfaac hasn't been supported by ffmpeg for years) mpeg4 is the most common web standard and .ts is the only format NextPVR reads natively

Martin

[Reddwarf]

That's easy (although libfaac hasn't been supported by ffmpeg for years) mpeg4 is the most common web standard and .ts is the only format NextPVR reads natively

Martin

Isn't MPEG4 Divx/XviD? It is different than libx264 as far as I understand...

[mvallevand]

Isn't MPEG4 Divx/XviD?

Kind of, but modern mp4 streaming is h264 or 3gp previously

Martin