Hi Gilles, On Wed, Feb 16, 2011 at 2:25 PM, Gilles Maire <[email protected]> wrote: > Hello > > Do you know how to merge two Yuv Images from their AVPicture Pointer ? > > > For example : > > Image 1 > > __ __ > / \~~~/ \ > ,----( .. ) > > / \__ __/ > /| (\ |( > ^ \ /___\ /\ | > |__| |__|-" > > > Image 2 > > > > ~~~~~~~ > > ( ° ° ) > > \ L / > > = > > result > > > __ __ ~~~~~~~ > / \~~~/ \ > ,----( .. ) ( ° ° ) > > / \__ __/ \ L / > /| (\ |( > ^ \ /___\ /\ | = > |__| |__|-" > > > > > Thanks :)
Might seem incredibly simple, but it's actually not, because how do you decide which pixels to keep and which to add? Simple filters do overlay-add, which means black pixels are considered "zero" and white "one", and then you "add" the signal of each color component in each pixel up. Obviously this only works in lab situations (e.g. think of microscope images in green/red/blue channel, adding them up gives a color image, as in Nature papers etc.), it would double the brightness of the background. More subtle filters set a background detection in one image and make that transparent and then add only the opaque pixels up into the other image. That's very complex however. This kind of stuff is what Photoshop (and the GIMP) do for you, I don't think FFmpeg has such filters yet. Ronald _______________________________________________ libav-user mailing list [email protected] https://lists.mplayerhq.hu/mailman/listinfo/libav-user
