OpenELEC Testbuilds for RaspberryPi Part 3 (Kodi 14.0)
(2014-09-24, 15:16)plugh Wrote: Can't comments on all your cases, but the bcm2835 driver (both analog and hdmi) does not declare support for S24_LE

Actually xbmc doesn't use alsa for hdmi/analogue outputs. It uses openmax directly (and does support 8/16/24/32/float audio formats).

Internally xbmc uses ffmpeg's libswresample for format conversion. However the Pi has a GPU accelerated path for this which means libswresample is not used.

I did suspect that the GPU path might have a bug with 24-bit formats, but I get get the same noise with the GPU accelerated path disabled.
This fact suggests the bug is not in ffmpeg's libswresample as I believe I'm seeing it with that path disabled

Note there are two examples of noise produced:
One when using HifiBerry, presumably with mostly float audio (the output of most of ffmeg's audio decoders) . This will probably exercise a float->S24_LE conversion.
One when using s24_le.wav with HDMI audio output. This will probably exercise a S24_LE->float conversion (I'll have to check exactly what AudioEngine chooses for the sink in this case).

Possibly there are two bugs. One is a general disagreement about where bytes go in a S24 WAV file.
The other is on the path from xbmc->hifiberry driver does something wrong with S24.


Messages In This Thread
Re: RE: - by Mafarricos - 2014-06-04, 20:21
Live tv issues again - by pootler - 2014-06-04, 23:29
RE: OpenELEC Testbuilds for RaspberryPi Part 3, - by removed151214 - 2014-08-04, 23:38
RE: OpenELEC Testbuilds for RaspberryPi Part 3 - by removed151214 - 2014-08-19, 00:11
RE: OpenELEC Testbuilds for RaspberryPi Part 3 - by removed151214 - 2014-08-21, 20:42
RE: OpenELEC Testbuilds for RaspberryPi Part 3 - by removed151214 - 2014-09-22, 22:20
RE: OpenELEC Testbuilds for RaspberryPi Part 3 - by removed151214 - 2014-09-22, 22:34
RE: OpenELEC Testbuilds for RaspberryPi Part 3 - by removed151214 - 2014-09-22, 22:44
RE: OpenELEC Testbuilds for RaspberryPi Part 3 - by removed151214 - 2014-09-23, 01:12
RE: OpenELEC Testbuilds for RaspberryPi Part 3 - by removed151214 - 2014-09-23, 23:24
RE: OpenELEC Testbuilds for RaspberryPi Part 3 - by removed151214 - 2014-09-25, 01:38
RE: OpenELEC Testbuilds for RaspberryPi Part 3 - by popcornmix - 2014-09-24, 15:36
RE: OpenELEC Testbuilds for RaspberryPi Part 3 - by removed151214 - 2014-10-01, 18:12
RE: OpenELEC Testbuilds for RaspberryPi Part 3 - by removed151214 - 2014-10-01, 18:26
RE: OpenELEC Testbuilds for RaspberryPi Part 3 - by removed151214 - 2014-10-05, 01:07
RE: OpenELEC Testbuilds for RaspberryPi Part 3 - by removed151214 - 2014-10-11, 03:48
RE: OpenELEC Testbuilds for RaspberryPi Part 3 - by removed151214 - 2014-10-11, 04:06
RE: OpenELEC Testbuilds for RaspberryPi Part 3 - by removed151214 - 2014-10-11, 11:29
Logout Mark Read Team Forum Stats Members Help
OpenELEC Testbuilds for RaspberryPi Part 3 (Kodi 14.0)8