On Mon, 16 Feb 2009 21:28:56 +0100 Thomas Hilber vdr@toh.cx wrote:
On Mon, Feb 16, 2009 at 11:48:50PM +1000, Torgeir Veimo wrote:
On 16 Feb 2009, at 23:29, Tony Houghton wrote:
And if the video has to be scaled it would have to scale each field separately then reinterlace them line-by-line at the output resolution
@Tony Houghton: is it really possible to scale each field separately without producing artifacts? Isn't deinterlacing always neccessary prior to scaling? IMHO scaling does imply that even lines are allowed to blur into odd lines if the scale factor forces this.
But artifact free blur of both fields is NOT possible if you either
- don't deinterlace prior to scale
or
- keep even and odd fields separated during scale
You're right. I was thinking of cases where there's a lot of movement and the fields are from different pictures, forgetting that they can alternatively add detail to static scenes.
Ok, I guess this single issue implies that vdpau is not fully suitable for displaying interlaced material with interlaced output.
@Torgeir Veimo: not sure about this. Intel series i9xx graphics is able to scale by hardware even in interlaced mode. I use this feature for my intel based frame rate control patches (SCART/RGB/PAL vga-sync-fields patch).
VDPAU is currently only on NVidia cards although it's possible Intel and even ATI may provide backends for it in the future. I think only the most recent Intel chipsets support H.264 decoding, does your patch work with those? Once there's a stable API for their H.264 decoding I guess we'll have the best of both worlds :-).