Plextor ConvertX PX-TV402U Audio Stream Capture doesn't work

[toehser]

Hi-

I'm trying to capture from the Plextor ConvertX PX-TV402U.

This device makes 2 things available over USB- a video stream which comes compressed already, either DIVX/MPEG4, MPEG-2, MPEG-1, or MJPEG; and an audio stream that comes as raw PCM.

VLC does OK with the video streams, I can capture video from the device with no problems, other than my own confusion.

But the audio stream doesn't show up in the Audio Device Name list, doesn't appear on 'refresh', and doesn't seem to be automagically working as a result of it being one of the streams from the Video Device.

I havn't found _any_ way to get VLC to capture _any_ audio from it.

Am I missing something?

The audio properties do show up in all the device configurations for the Video device.

But it seems like VLC just doesn't see the device as an audio source...

???

-Tom

[DJ]

Try selecting your audio card as the source and then adjusting the record volume for either line in if that is where you have plugged in the audio cable or wave if there is no cable.

[toehser]

I don't think you understand. The audio input is not hooked up to one of the sound card inputs that are seen by VLC. The audio input is hooked up to the inputs on the Plextor. VLC only sees the WDM audio devices, but the Plextor is a DirectShow source, I guess they call the sound part DirectSound? And isn't showing up in the list. It isn't a question of Line In vs. Wave In or anything like that. VLC sees the Realtek AC97 on the motherboard, and it sees 10 devices from my Creamware Luna, which has 1 SPDIF input, 1 Analog input on the card, and 8 inputs from the external firewire connected A/D box. But VLC _isn't even seeing_ that the Plextor is an audio source. Maybe if VLC sees WDM audio sources it doesn't look for DirectSound devices? Maybe it doesn't support DirectSound devices? Certainly selecting one of the audio devices which has nothing hooked up to its input is not going to help. Help?

[toehser]

Note: I see discussion that people are having (what seems like) the same problem with something called a 'hauppage 350'.

Apparently, there is some thinking that the 'default' audio device is supposed to get the audio from the DirectShow device? But apparently the Plextor is not the only card for which this isn't working, or else it really *doesn't* work like that.

On the other threads, people just gave up and connected the audio to a different soundcard.

How can I go about debugging the audio source detection? Is the sound part of a DirectShow device even supported?

-Tom

[toehser]

More info-

The "default" audio device is doing just that- whatever the *windows* default audio input is- _not_ the audio pin of the video capture device...

As far as I can tell, VLC is showing _only_ the WDM audio inputs, it isn't seeing the audio stream of the DirectShow device at all, only its video stream...

Any ideas on how I can debug this, or is this just not a feature of VLC?

-Tom

[Aspirax]

Anyone have any input on this? I have a similar setup, and the audio device is uncaptureable.

Thanks!

(The software, DVD Creator, that comes with the device is able to do this... But i don't care for that software!)

[DJ]

This post is to confused to respond to directly.

Manufactures of capture devices have chosen the do audio and video separately (no container). Originally the audio was PCM (2s compliment) so that this could fed to an on-board converter and plugged into your sound card's line input. When manufactures discovered that they could send the sound over the same interface as the video (USB, Firewire and etc.) the Direct Show drivers were rewritten. But there has never been a standard and the drivers have always been written specifically for the device. As such many manufactures continued to offer a line out of their device. When the Audio does not show up in VLC but the video does, using the manufactures Direct Show Drivers, it could be a problem of recognition of that driver or more likely is a problem within the driver. The driver may be forcing recognition within the Direct Show codecs which will not work with VLC.

Perhaps one of the Devs will respond to this one.

[Aspirax]

Thanks for your inputs. GBPVR is able to capture the audio and the video from the device directly. It uses something called the "GO7007SB" recording plugin.

I apologize if the post is confusing, I didn't start it, but since I was having the same issue, it made sense!