I know the difference, the problem is, the user who doesn't go digging
through code would have no indication that changing the sample rate for
recording profiles of an mpeg device would have negative effects, which
aren't immediately obvious. Why would I change the rate you ask? The
default alsamixer settings for my audio card (which uses the Via Envy24
chipset) sets "multi track rate locking" to on, so I set the alsamixer
multi track sample rate to 44.1kHz so that it would work with TV and
music. I changed the recording profile rates to 44.1kHz and didn't
realize there was a problem for a few weeks because this only happens
when watching recordings as they're recording or buffered live TV which
I do very rarely.
Donavan Stanley wrote:
On 8/29/05, Larry Symms <[EMAIL PROTECTED]> wrote:
In mpegrecorder.cpp it states "// only 48kHz works properly." regarding
audio sample rates which I have tested and proven true. What happens is
a discrepancy in displayed time and actual position in the recording.
This leads to skipping back when trying to skip forward because myth is
miscalculating the current position based on time elapsed. The problem
is that the comments in Recording Profiles in TV Settings in Myth
frontend say: "Sets the audio sampling rate for your DSP. Ensure that
you choose a sampling rate appropriate for your device. btaudio may
only allow 32000." This implys that not only is it ok to change the
sampling rate from the default but that it is recomended. This is not
the case. Do not be deceived, 48000 is the only acceptable setting for
mpeg encoders unless you never watch recordings while they're
recording. When playing recordings while they are recording the sample
rate is gathered from the codec settings in the db rather than the mpeg
header. If any of this is incorrect by all means correct me but I'm 99%
sure this is the case based on the code I've gone through and the tests
I've conducted.
The big thing you appear to be missing is the btaudio and mpegrecorder
have nothing to do with each other. If you have a card which uses
btaudio you're going to be using nupplevideoencoder.
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