[mythtv-users] IPTV recorder seems broken -- large jumpy files

[Dan Wilga]

On 4/6/18 9:54 AM, Rajil Saraswat wrote:
> On 04/06/2018 08:35 AM, Dan Wilga wrote:
>> On 4/6/18 8:56 AM, Rajil Saraswat wrote:
>>> On 04/06/2018 06:52 AM, Greg Thompson wrote:
>>>> Why are your fps jumping around so much? It looks like maybe your
>>>> ffmpeg command line needs tweaked.
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>>> It seems to work fine if I run it independently in cli. Also, I have
>>> noticed that if i use the IPTV recorder in mythtv the stream works fine.
>>> It is only when using External recorder with ffmpeg when things break
>>> down. Could this be related how fast Mythtv wants to read from ffmpeg
>>> and how quickly can ffmpeg deliver?
>> In my attempts to get the Blackmagic DeckLink to record with Myth, I
>> ran into similar problems. It wasn't until I modified mythfilerecorder
>> to allow for the stdout of a program (like ffmpeg) to be sent
>> unbuffered to the backend that things started to work. You can see my
>> patch here, if you want to try it:
>>
>> https://code.mythtv.org/trac/ticket/13251
> Does your patch improve the External Recorder or do i need to setup a
> new tuner type?
>
> At the moment i simply use ffmpeg like so with External Recorder,
>
> ffmpeg -i "udp://@239.255.42.42:5004" -acodec copy -vcodec copy -f
> mpegts - &
Interesting. According to the wiki:

   https://www.mythtv.org/wiki/ExternalRecorder

an external recorder needs to implement a set of back-and-forth 
commands, which using ffmpeg directly would not do. I'm not sure I ever 
even tried it without (my modified) mythfilerecorder doing the command 
parsing.

Perhaps this is the reason it's not working well for you? If you have 
the source code set up to compile, it's worth a try.