More information: when a HD broadcast cuts to SD, the audio codec seems to change. MediaPortal doesn't notice this unless you manually force it to by changing the audio language, and that's where we get the really odd audio. Strange thing is: after you change the audio track, everything is in really deep, slowed down voices.
BlackGold BGT3620 DVB-T2 card - Where are the HD channels? (2 Viewers)
- Thread starter hoverdonkey
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- September 1, 2008
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High squeeky voices and fast talking or low slow voices indicates that the codec is not properly handling the audio sample rate. Sounds like we need to look for an alternative audio codec...
DivX is a piece of crap. For video, I've switched back to Microsoft's DTV-DVD codec. I will see if I can find another LATM-AAC codec.
- September 1, 2008
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Couldn't agree more, but that won't solve your problem for live TV. I looked at the code the other night to see why the MS audio codec wasn't available in the LATM-AAC list. The list isn't hardcoded, so it will require further investigation...
Microsoft MPEG-1/DD/AAC Audio Decoder (Windows)
"Microsoft MPEG-1/DD/AAC Audio Decoder
This filter decodes the following audio formats: [...]
* Advanced Audio Coding (AAC) Low Complexity (LC) profile.
* High-Efficiency AAC (HE-AAC) version 1 and version 2.
[...]
The DirectShow decoder supports the following AAC input types: [...]
* MEDIASUBTYPE_MPEG_LOAS: Transport stream with a synchronization layer (LOAS) and a multiplex layer (LATM)."
Sounds like it just didn't register somewhere. Can I manually set the decoder to use?
The Microsoft DTV-DVD video decoder is excellent. I don't know why, but I was having major frame drops until I switched to it. (I am not ruling out coincidence, but CPU load is now very low, it must be nicely hardware accelerated.)
Edit: Just noticed I'm dangerously close to duplicating another thread on this, which I found when trying to solve the problem. So I'll keep playing and report back.
"Microsoft MPEG-1/DD/AAC Audio Decoder
This filter decodes the following audio formats: [...]
* Advanced Audio Coding (AAC) Low Complexity (LC) profile.
* High-Efficiency AAC (HE-AAC) version 1 and version 2.
[...]
The DirectShow decoder supports the following AAC input types: [...]
* MEDIASUBTYPE_MPEG_LOAS: Transport stream with a synchronization layer (LOAS) and a multiplex layer (LATM)."
Sounds like it just didn't register somewhere. Can I manually set the decoder to use?
The Microsoft DTV-DVD video decoder is excellent. I don't know why, but I was having major frame drops until I switched to it. (I am not ruling out coincidence, but CPU load is now very low, it must be nicely hardware accelerated.)
Edit: Just noticed I'm dangerously close to duplicating another thread on this, which I found when trying to solve the problem. So I'll keep playing and report back.
- September 1, 2008
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Yes, there are several active threads about DVB T2 at the moment. I'm pretty sure that the reason that the Microsoft audio codec isn't available is because the LATM-AAC media subtype isn't picked up, but I'll have to confirm that. You can't manually choose the codec I'm afraid - I think this will require a code change...
The MS video codec does provide hardware acceleration. Some codecs play nicely together and others don't. Add in the content and some codec combinations will work and some won't...
0002831: Add NALU support for audio streams (aac) in TsReader - MediaPortal Bugtracker
Not all audio codecs would accept the AAC stream type that TsReader is providing. So, the change wont be that easy. I'm not sure if MS decoder accepts the current stream type (non-NAL or what ever you would like to call it
).
Not all audio codecs would accept the AAC stream type that TsReader is providing. So, the change wont be that easy. I'm not sure if MS decoder accepts the current stream type (non-NAL or what ever you would like to call it
).- September 1, 2008
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Hi tourettes
I wanted to at least try and force the MS codec into the list and see what happens. I mean, we've got nothing to lose by trying it
Of course this is *completely* outside my area of "speciality" so I defer to you on this...
I wanted to at least try and force the MS codec into the list and see what happens. I mean, we've got nothing to lose by trying it
Of course this is *completely* outside my area of "speciality" so I defer to you on this...
I wanted to at least try and force the MS codec into the list and see what happens. I mean, we've got nothing to lose by trying it
It is worth to try, since it is codec specific if they will accept the stream (it was same at the video codec side).
- October 19, 2008
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I have the following experience with various H.264 video codec options, in descending order of success;
"Microsoft DTV-DVD Video decoder" - is stable, but not perfectly smooth - there is continuously slightly jerky playback, like it is dropping frames.
"ffdshow DXVA" (SAFv5) & "DivX H.264" - both give smooth playback for the first few minutes. If I try to go back to TV menu or guide during this time, then video grinds to a halt, sound continues and then after a few minutes of this, MP stops working. I get the same symptoms if I just leave it playing for a few minutes, pressing no buttons.
"MPC - Video decoder" (SAFv4) - does not work at all, MP hangs when switch to an HD channel.
"Microsoft DTV-DVD Video decoder" - is stable, but not perfectly smooth - there is continuously slightly jerky playback, like it is dropping frames.
"ffdshow DXVA" (SAFv5) & "DivX H.264" - both give smooth playback for the first few minutes. If I try to go back to TV menu or guide during this time, then video grinds to a halt, sound continues and then after a few minutes of this, MP stops working. I get the same symptoms if I just leave it playing for a few minutes, pressing no buttons.
"MPC - Video decoder" (SAFv4) - does not work at all, MP hangs when switch to an HD channel.