Direct Show capture pb with high definition capture card

[thomasferre]

Hi

I am using VLC 1.0.5 on a PC under windows XP to do live H264 high definition multicast streaming.

I have installed a XTREME RGB high definition card :

http://www.ems-imaging.com/catalog/modu ... cts_id=116

Datasheet

http://www.ems-imaging.com/catalog/modu ... fa0d54977e

This HD capture card enable a full HD 1920*1080 at 60 fps capture.

This card is provided with a direct show driver (last version 4.4.2.2 from EMS IMAGING)

We are using an HD 1080p camera as an input.

When capturing video from the direct show driver with VLC WITHOUT transcoding (only displaying raw HD signal), it produces some choppy frame from time to time (as if a few frames were missed).

I thought that this pb may come from the driver card.

So I installed AMCAP.

With the same card and the same driver on the same machine, the capture is perfect with AMCAP (not a single missed frame).

So the pb does NOT come from the driver itself but it comes from the way VLC 1.0.5 handle capture from a direct show driver.

Indeed, HD capture is a lot different from a PAL SD capture (a lot more information to capture).

So I thought maybe the capture source code was not fitted with full HD 1920*1080 at 60hz capture (such as time lag between each capture frame or ...).

I also notice on VLC 1.0.5 that some chromas were working fine with AMCAP but not with VLC :

- YVYU not working on VLC, OK with AMCAP

- RGB32 produces upside down image with VLC, OK with AMCAP

- RGB24 produces a blue image with VLC, OK with AMCAP

- RGB565 produces blue AND upside down image with VLC, OK with AMCAP

I know it is a very specific HD problem (I am using another SD PAL OSPREY 100 capture video with no pb with VLC).

How can I contact the developpers of the direct show capture source code of VLC ?

Thanks for your help.

Regards

[VLC_help]

VLC's directshow capture support isn't the best possible. So dropped frames may happen. Some colorspace (chroma) issues are fixed in VLC 1.1.0, but some aren't.

[yuer1108]

I face color space problem also.
I use a VGA capture card to capture VGA input signal from a computer. vlc player show "lack-color" picture.

[VLC_help]

You can try different colorspaces (via --dshow-chroma= or GUI option) like I420,IYUV or YV12 and see if any one them works better.

[yuer1108]

yes, I've changed another vga capture card which support I420. also I can confirm the RGB's color space can not be used in vlc R1.0.3.
(RGB 24 will show "yellow" picture, RGB565 will upside donw)
and R1.1.0 will support RGB24 in my RGB24's vga capture card, but I can not use R1.1.0 since it is not stable for me.
btw, uYvY and YuY2 is OK in r1.0.3 for EPIPHAN's vga capture card(of cause RGB have problem).