Overlay/Preview Control?

[PCGuy760]

I have a Genie TV Capture Card and when I try to look at TV on the PC with this Card, it will not show the picture if I select overlay mode - just a still pic that seems to look good quality. BUT when I select preview, it shows the live video in bad, blocky quality.

How can I get it to show the live video in good quality or possibly in overlay mode??

Plz Help!
Note : This card is based on the BT878 Chip.

[stanwebber]

i think it's down to your videocard not supporting video overlay mode or you're trying to run it in a ridiculously high resolution

[TheInformer]

What graphics card are you using? Not all graphics cards support overlay mode, which must be done in hardware. Also, AGP cards are preferable to PCI based ones.

Overlay mode, as far as I know, can only work with a vertical resolution (lines) of 240. Anything higher and you will get an error saying something to the effect that "you don't have enough memory" or similar.

Preview mode is where the CPU actually handles the blits from the TV card to the display card. This can slow things down tremendously on a system, and in my experience the display looks terrible compared to overlay mode. You can capture above 240 lines in preview mode but be prepared to lose frames.

[PCGuy760]

Thanks for the replies! I am using a Nvidia Riva TNT2 M64 32Mb AGP Card with a 1Ghz Athlon Thunderbird Classic 266FSB.
I am using the latest Detonator Drivers from Nvidia which I downloaded about a 4 days ago.

My Video Settings for displaying are 320x240 with YUV12.

I hope this makes it more clear now sorry for not giving details before. Hope You guys can help me figure this out!

Thx


<font size=-1>[ This Message was edited by: PCGuy760 on 2001-10-19 13:17:18 ]</font>

[Shabubu]

Only use overlay/preview mode to set up your capture. When capturing you should disable the preview and listen to the audio to decide when to start and stop.

[skittelsen]

As for using overlay/preview during capture, on my system it has no effect on dropped frames. I guess it will depend on the system, and where the bottleneck is.