On Tue, 25 Apr 2006, chris clepper wrote:
On 4/25/06, B. Bogart ben@ekran.org wrote:
I still could not get pix_chroma_key to key on "value 16,16,16" remember our green is 0,240,0 not 0,255,0. (which I guess is YUV 0,0,0)? what should the YUV range be like for this video?
I may have bungled some of the code in that object. Try 128, 50, 50 and a range of 30 or so for a green background. I was able to key out a fairly typical green screen with that.
there's [rgb2hsv], [hsv2rgb], but do [rgb2yuv] and [yuv2rgb] exist yet?
There's [#rgb_to_yuv] and [#yuv_to_rgb] which works for both single pixels and whole pictures, but they use JPEG-style yuv, which goes 0..255 instead of the legacy range 16..239 (and such) which are due to NTSC/PAL voltage specifications. (Both ranges of YUV are in wide use).
_ _ __ ___ _____ ________ _____________ _____________________ ... | Mathieu Bouchard - tél:+1.514.383.3801 - http://artengine.ca/matju | Freelance Digital Arts Engineer, Montréal QC Canada