[mythtv-users] mythtv v30 'Could not open decoder' error
Mike Bibbings
mike.bibbings at gmail.com
Thu Jan 31 17:45:07 UTC 2019
On 31/01/2019 14:47, Tim Pletcher wrote:
> On Tue, Jan 29, 2019 at 2:11 PM Tim Pletcher <pletchtd at gmail.com
> <mailto:pletchtd at gmail.com>> wrote:
>
> On Tue, Jan 29, 2019 at 10:28 AM John <jksjdevelop at gmail.com
> <mailto:jksjdevelop at gmail.com>> wrote:
>
> I also get this error on a remote frontend with version 30.
> Some timeout must need a tweak. Note the issue has been there
> for several weeks it is not due to a very recent change. I
> don't use live tv enough to make it a major issue for me.
>
>
>
> Good to know that the problem is not unique to me. I only updated
> to v30 on Sunday the day prior so it is likely that I simply
> didn't stumble upon it in the limited use of the system since then.
>
> According to this in the log:
>
> Jan 28 19:28:13 k-mint mythfrontend.real: mythfrontend[1273]: I CoreContext avformatdecoder.cpp:2772 (OpenAVCodec) AFD: Opened codec 0x55a532b95180, id(AC3) type(Audio)
> Jan 28 19:28:13 k-mint mythfrontend.real: mythfrontend[1273]: E CoreContext avformatdecoder.cpp:2635 (ScanStreams) AFD: Unknown video codec - defaulting to MPEG2
>
> It appears that this is related to fallback to software based
> decoding rather than GPU Hardware based decoding. Since this is
> occurring intermittently, you are probably right that it is a
> timing issue.
>
> Looking at avformatdecoder.cpp and totally speculating because i
> have no experience with C++, I wonder if is related to
> SEQ_PKT_ERR_MAX10 (line 108) which is a criterion used to apply
> logic to fall back to software decoding? Is 10 packets perhaps
> sometimes too sensitive when changing channels via LiveTV?
>
> I pulled down the source, increased the SEQ_PKT_ERR_MAX value to 15 in
> avformatdecoder.cpp, and recompiled the frontend. Since doing that, I
> have not experienced the 'Could not open decoder' error for the last
> three days now when using LiveTV. I have not noticed any other
> deleterious effects though I will continue to monitor for any.
>
> On a separate topic, when I recompile the frontend from source, the
> mythfrontend binary I generate is an order of magnitude larger than
> the one in the mythbuntu repo and I can't seem to figure out why.
> Looking and comparing the ./configure options from the mythbuntu build
> package with the ones I am using, the only tangible difference i see
> is that my system is using NASM rather than YASM for the compilation.
> Can anyone educate me on what is causing this difference?
>
> -Tim
>
>
Tim,
I tried your change to SEQ_PKT_ERR_MAX on current mythtv master and it
did not resolve the problem. I also tried other values of 50 and 1000,
again no resolution.
For reference my system is Xubuntu 18.04 with Hauppauge QuadHD DVB-T/T2
using current Hauppauge kernel from the ppa.
My workround is attached, it disables error checking in
avformatdecoder.cpp, and only affects LiveTV.
Mike
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mythtv.org/pipermail/mythtv-users/attachments/20190131/3caff0a3/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: disable_avformatdecoder_return_FAIL_DEBUGONLY.patch
Type: text/x-patch
Size: 613 bytes
Desc: not available
URL: <http://lists.mythtv.org/pipermail/mythtv-users/attachments/20190131/3caff0a3/attachment.bin>
More information about the mythtv-users
mailing list