[mythtv] [PATCH] Mac OS X audio patch

[Nigel Pearson]

> Just so Nigel doesn't have to do all the work on the OS X port, a 
> patch is attached for Core Audio output under Mac OS X.

	Jeremiah, thank you, thank you, thank you, thank you.
I was wondering how I was going to translate 48KHz little-
endian ints to 41KHz big-endian floats, and you have done
the hard work for me.

	I still want to write a raw-device level driver so that
Darwin/X11 users can get sound, but this is great.

	Don't suppose you know how to drive the HAL directly?


>   It's been (lightly) tested under 10.3.  Works pretty well in 
> audio-only mode (my test Cube can't keep up on the video, with or 
> without sound).

	Playing back a clip is OK for about a second, but then it stutters.
This could be a CPU load thing (my box only just keeps up with the 
video),
or it could be some bug in the timing. NVP outputs:

Input #0, mpeg, from 
'myth://143.238.2.191:6543/1002_20040810210600_20040810222000.nuv':
   Stream #0.0: Video: mpeg2video, 720x576, 25.00 fps
   Stream #0.1: Audio: mp2, 48000 Hz, stereo, 256 kb/s
VideoOutputQuartz::Init(width=720, height=576, aspect=1.777778, winid=11
                         winx=0, winy=0, winw=1024, winh=768, WId 
embedid=0)
2004-08-30 15:07:24 Changing from None to WatchingPreRecorded
clipped negative delay: -267327512
clipped negative delay: -11288
clipped negative delay: -31852
clipped negative delay: -31871

	before it starts stuttering, and then lots of similar lines:

clipped negative delay: -13534
clipped negative delay: -137755
clipped negative delay: -310
clipped negative delay: -125538
clipped negative delay: -127112
clipped negative delay: -56101
clipped negative delay: -206557
clipped negative delay: -81674
clipped negative delay: -126628

	afterwards.


	If I redirect this output to /dev/null, it doesn't stutter
and mostly keeps up. Sometimes the video is delayed, but it only
lasts about 0.5 seconds, and then audio is back in sync.

	Give that a try!

--
Nigel Pearson, nigel at ind.tansu.com.au | "Peacemaking is our profession"
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