[mythtv] A need for advanced player settings
mark.kendall at gmail.com
Tue May 31 03:37:58 UTC 2011
On 31 May 2011 11:25, Kyle Rose <krose at krose.org> wrote:
>> Apologies for the late response. Can you provide a link where we can
>> download the problematic file? From memory, matroska doesn't take well
>> to being clipped randomly so I'm assuming it will need to be the whole
> I took a 750MB prefix of the file in question, which seems to play
> fine. Here it is (for the next 72 hours):
Thanks - downloading now.
>> This does tie into some issues that a couple of people have been
>> trying to debug in the last couple of weeks. There was a suggestion of
>> incorrect bitrate detection and/or updates with one file and it
>> obviously ties up with the symptoms.
> Does Matroska store the maximum bitrate of a variable bitrate stream
> anywhere? That would be sufficient information to solve this
> particular problem, but I don't know enough about Matroska.
I've been doing some digging and it seems not (and that seems to be a
>From testing with another problematic file, my gut feeling is that the
root cause is the bitrate detection in AvFormateDecoder::ScanStreams.
For the broken files, the H264 bitrate is detected as zero and there
is a long standing hack to force that to 500000bps (line 1751 in
master). I was hoping that forcing that to something much higher would
fix playback and, while not being a long term fix, would prove the
point. Unfortunately, it didn't...
Which either suggests I'm completely wrong or there is some additional
complexity I've missed.
Thanks and regards
More information about the mythtv-dev