Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Highlighted
Beginner
3 Views

Optimized RGB and RGBA Compositing

Is there anything in the IPP that will accomplish using the Alpha channel of RGBA image to overlay the RGB components onto an RGB image or to a new image?  I've taken a look at the ippiAlphaComp() functions, but they do not seem to allow mixing of C4R and C3R.

Basically looking for this:

SourceB = RGB image

SourceO = RGBA image

SourceB = (SourceO x SourceO) + (SourceB x (255 - SourceO))
SourceB = (SourceO x SourceO) + (SourceB x (255 - SourceO))
SourceB = (SourceO x SourceO) + (SourceB x (255 - SourceO))

 

0 Kudos
2 Replies
Highlighted
Employee
3 Views

Hi Shane,

yes, mixing in this case doesn't work. Possible way is to convert C3 image to AC4 (ippiCopy_8u_C3AC4R), fill A channel with "1" and then use ippAlphaOver function that applies aA*A+(1-aA)*aB*B formula. I guess it will be too expensive from the performance point of view and it's better to use the simple loop in your code.

regards, Igor

0 Kudos
Highlighted
Beginner
3 Views

I ended up asking a similar question on stackoverflow, here is the link that will hopefully aid someone else.

http://stackoverflow.com/questions/22018826/implement-a-near-real-time-cpu-capability-like-glalphafu...

0 Kudos