MediaPortal Audio renderer - better video playback quality (3 Viewers)

red5goahead

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    57 downloads on the latest audio renderer & dshowhelper binary and not that many replies? I guess the renderer is working quite nicely.

    A quick update on the AC3 / SPDIF re-encoding on the fly. Proof of concept is working on my dev PC. I can now re-encode 2 channel audio to the AC3 instead of passing it directly as (L)PCM. AMP shows the "Dolby Digital 2.0" correctly and there is no pops nor clicks. But it is only POC and requires more work to get it to integrated with the multichannel code after it has been done.

    Good. An update with the first version of on-fly Ac3 encoder , even with 2 ch only, can be usefull to test some kind of delay of that stream. As you known , I told you some posts ago, I switch my system with the open source driver for C-media 8768+/8770 , so I shutdown the ac3 on board features to be ready to compare the reclock encoding to this one. Infact with reclock there are some kind of issue about audio delay. With audio ffdshow the proper delay for ac3 encoding , even 2.ch, is about +20 - +30 ms to synch audio and video . Imho this could be a tuff challenge for the new audio renderer. Do you think already to modify the MP config program to allow us to select the proper audio devices ? now should be two . the default one, and the digital for the bitstreaming.
    which Amp you choose then? ;)
     

    mironicus

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    AW: Re: MediaPortal Audio renderer - better video playback quality

    Sounds like NVIDIA's drivers wont work with the event driven WASAPI mode. When playing with non-exclusive mode please make sure that the graph actually has the MP audio renderer in use and not the default directshow one.

    Isn't it so that WASAPI exclusive mode just don't work or is limited with NVidia GPUs? I just read that in AVSforums.com. :)
     

    tourettes

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    Re: AW: Re: MediaPortal Audio renderer - better video playback quality

    Sounds like NVIDIA's drivers wont work with the event driven WASAPI mode. When playing with non-exclusive mode please make sure that the graph actually has the MP audio renderer in use and not the default directshow one.

    Isn't it so that WASAPI exclusive mode just don't work or is limited with NVidia GPUs? I just read that in AVSforums.com. :)

    Quote from one of the Microsoft's audio software engineers for Vista & Windows 7 -

    Wasapi exclusive streaming :

    All audio drivers support Exclusive mode, it's an aspect of the audio engine, not the driver.

    Of course the driver(s) could be broken, but that indeed is an issue with the HW manufacturer.
     

    tourettes

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    A quick update on the AC3 / SPDIF re-encoding on the fly. Proof of concept is working on my dev PC. I can now re-encode 2 channel audio to the AC3 instead of passing it directly as (L)PCM. AMP shows the "Dolby Digital 2.0" correctly and there is no pops nor clicks. But it is only POC and requires more work to get it to integrated with the multichannel code after it has been done.

    Good. An update with the first version of on-fly Ac3 encoder , even with 2 ch only, can be usefull to test some kind of delay of that stream.

    I'll consider releasing a work-in-progress preview of the AC3 encoding feature with 2 channel limit. It will depend how much the multichannel support itself will take (if quite long, then I'll release some binary to be tested).

    Infact with reclock there are some kind of issue about audio delay. With audio ffdshow the proper delay for ac3 encoding , even 2.ch, is about +20 - +30 ms to synch audio and video . Imho this could be a tuff challenge for the new audio renderer.

    I haven't yet paid any big attention to the lipsync with the AC3 encoding. At least it seems to be ok on 1:1 PAL material, but who knows if it is wrong it some specific files or the speed up audio & video.

    Do you think already to modify the MP config program to allow us to select the proper audio devices ? now should be two . the default one, and the digital for the bitstreaming.

    Since currently the audio renderer's main target is MP2 I doubt there will be any config side changes for MP1. But if we are lucky, depending how te bitstreaming is implemented on ffdshow side we might not require any settings and the audio renderer would just work.

    which Amp you choose then? ;)

    Onkyo TX-SR508.
     

    red5goahead

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    Do you think already to modify the MP config program to allow us to select the proper audio devices ? now should be two . the default one, and the digital for the bitstreaming.

    Since currently the audio renderer's main target is MP2 I doubt there will be any config side changes for MP1. But if we are lucky, depending how te bitstreaming is implemented on ffdshow side we might not require any settings and the audio renderer would just work.

    Mhh . I did not understand . For bitstreming should be used the digital device not necessary the default one (typically the named "speaker" one). How do you choose it when multichannel will be allowed? The audio renderer should use the main device for the streams with 2 ch. and the digital device for bitstreaming. So in this first step we have to select digital device as default to test properly in MP 1.x environment ?
     

    davidf

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    Thanks for that and I'll add the extra bit for other ION users
    WASAPIExclusive also needs to be set to 0 or there is no sound.

    It has resulted in a much smoother picture with practically no stuttering.

    Sounds like NVIDIA's drivers wont work with the event driven WASAPI mode. When playing with non-exclusive mode please make sure that the graph actually has the MP audio renderer in use and not the default directshow one.

    You were correct the Nvidia drivers don't work and with non-exclusive - the renderer is in the graph but not connected.
     

    tourettes

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    Thanks for that and I'll add the extra bit for other ION users
    WASAPIExclusive also needs to be set to 0 or there is no sound.

    It has resulted in a much smoother picture with practically no stuttering.

    Sounds like NVIDIA's drivers wont work with the event driven WASAPI mode. When playing with non-exclusive mode please make sure that the graph actually has the MP audio renderer in use and not the default directshow one.

    You were correct the Nvidia drivers don't work and with non-exclusive - the renderer is in the graph but not connected.

    Too bad since it means that the NVIDIA HDMI drivers are quite poor and dont work with the event driven mode at all (at least not with the MP audio renderer). I think I have seen that already happening on my dev PC (with HDMI + monitor connection) but I haven't paid any deeper atenttion into that. I'll have a look on that issue at some point.
     

    tourettes

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    Here's a work-in-progress preview of the AC3 ont-the-fly encoding. Currently same restrictions apply as previously for the audio renderer (2 channels etc).

    This binary is mainly intented to get some general feedback about 1) does AC3 light shine bright on the amplifier 2) does audio sound ok.

    To enable the AC3 encoding you need to set EnableAC3Encoding registry key to 1. Also make sure that WASAPIPreferredDevice is set to a device that is the SPDIF connection. DirectSound is most likely not working at all (not tested).
     

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    • mpaudiorenderer_AC3_test.zip
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    tourettes

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    Mhh. no lucky.

    take a look.

    Code:
    02-08-2010 18:52:51.681 [  c9c] Target end point: {5e35d45b-a94d-49d8-8ea4-726315a24a04}
    02-08-2010 18:52:51.681 [  c9c] GetAvailableAudioDevices
    02-08-2010 18:52:51.682 [  c9c] Unable to find selected audio device, using the default end point!

    registry should contain the whole string {0.0.0.00000000}.{5e35d45b-a94d-49d8-8ea4-726315a24a04}. Do not ask from me what those 0.0.0... are, but they are needed when talking with the WASAPI.
     

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