[mythtv] [mythtv-users] Problem Audio on Freeview HD BBC Channels

[David Matthews]

On 03/10/2011 22:13, Jean-Yves Avenard wrote:
> Hi
>
> On Tuesday, 4 October 2011, Simon Jones<sijones2010 at gmail.com>  wrote:
>
>>   well, I found the change they did, here
>>
> http://git.videolan.org/?p=ffmpeg.git;a=commit;h=0bc5d4fd8bbb63be172978e888834a88a1e64fb0
>
>
> According to the bug report, the bugs was fixed, marked as not fixed then
> fixed again. So I'm guessing the fix is made of more than one commit
>
>>   got trunk and altered the file but when I tried to compile it failed
>>   at some other place, it did compile FFmpeg ok tho, so would anyone be
>>   willing to try it for me?
>
> It was my intention to actually looked into back porting that change as it
> affects the audio and I know how difficult a resync is.
>
> If someone could provide a sample of the original content revealing the
> problem: a sample with a change of audio config it it.
>
> Thanks
> JY

I've been trying out a simple patch that fixes the problem for me.

--- a/mythtv/libs/libmythtv/avformatdecoder.cpp
+++ b/mythtv/libs/libmythtv/avformatdecoder.cpp
@@ -4104,6 +4104,11 @@ bool AvFormatDecoder::ProcessAudioPacket(AVStream 
*curstream, AVPacket *pkt,
          if (ret < 0)
          {
              LOG(VB_GENERAL, LOG_ERR, LOC + "Unknown audio decoding 
error");
+            // Hack - handle audio change on FreeView HD
+            avcodec_close(ctx);
+            ctx->codec = 0;
+            HandleStreamChange(this);
+            // Hack
              return false;
          }

I thought it was a hack so I didn't open a ticket for it.  It just 
handles the error that ffmpeg generates and rescans the stream.  I found 
it wouldn't work with the fixes branch so it presumably it requires some 
of the updates to ffmpeg that are only in git head.

David

(resent from the correct email address)