On 04-10-28, at 20:41, chris clepper wrote:
On Oct 28, 2004, at 2:00 PM, Etienne Desautels wrote:
Hi Chris,
Thanks for your answer.
I just replace my pix_image object with pix_film and it works. I also send it a RGB colorspace message at loading time, this way PNGs are showing fine. Without the RGB message, JPGs are showing fine but not PNGs. Do you have any ideas why it works with JPGs and not PNGs?
Quicktime will convert YUV to RGB automagically, but not the other way around. pix_film defaults to YUV because it is the proper color-space for video and also quite a bit faster than RGB. PNG images are RGB with lossless compression, while JPEG are YUV with lossy compression applied.
Oh! I didn't know that JPEG was in YUV. I was thinking that most image format were in RGB. That probably also explain why JPEG are loaded faster then PNG? Thanks for the explanation.
I just think about a question that I have for quite some time. I'm using pix_video with a firewire webcam to do some motion tracking/presence detection. I would like to adjust the settings of the webcam (color balance, brightness, etc.) but when I send a dialog message to pix_video, the normal QT dialog open and then pd freeze. I have to hit ^-C to quit pd. Do you have any ideas on this ?
Etienne