PVR-350 Only 16bit TV-OUT???

Jack_GB · 2004-05-01, 12:47 PM

NOticed with the pictures plugin that the 350's TV output is only 16bit, and banding shows in skys etc.

Is that a limitation of the 350's TV out or the plugin or GB-PVR?

***sub*** · 2004-05-01, 05:16 PM

I currently have the OSD set to 16-bit. I was finding the OSD updates far too slow on slow machine when I used 32-bit. The only thing this affects is the OSD which includes the pictures plugin.

This does not affect video played back through the PVR350.

Jack_GB · 2004-05-01, 08:25 PM

Any way to toggle it ?

***sub*** · 2004-05-01, 08:30 PM

You use to be able to but I've had it disabled for while. Believe me, it only affects the OSD graphics. I can also switch it into 8-bit/256 color mode. Video is handled independently of the OSD.

Jack_GB · 2004-05-01, 11:12 PM

AS you mentioned, it was just the photos that looked off. If speed is the only issue then maybe allowing users to configure it again might be an idea to consider...

Thanks for the quick feedback!

***sub*** · 2004-05-01, 11:14 PM

I'll add it to the todo list to renable this, but it'll require a little work so you probably wont see it for a couple of releases.

BerkA · 2004-05-03, 02:32 AM

Sub,
I don't know how you (or HCW drivers) handle the OSD on the 350, but I noticed that the CT23415 supports "hardware BITBLT acceleration." This feature could speed up the OSD for some operations.

***sub*** · 2004-05-03, 02:52 AM

You need to move the image into device memory before doing the BITBLT. This is the slow bit.

I can only really see the BITBLT being using for drawing small images that are often shown. There is not enough memory to store more than a couple of screens (which is what I do).

BerkA · 2004-05-03, 05:45 AM

I had this type of stuff in mind for BITBLT:
+ highligting button edges
+ OSD animation
+ OSD alpha changes (if that can be separate than the RGB)

The above stuff seems to be most of what's going on.

Getting the data on the framebuffer is another story. Are you doing DMA or is this a byte-by-byte write?

***sub*** · 2004-05-03, 06:30 AM

Transfer by DMA. Its not worth the effort for me doing this type of very very PVR350 specific BITBLT optomization. The current approach is more compatible with other devices such as the MVP and XCard.

Also, the current PVR350 OSD approach works fine so no real need for changes...