This commit adds a support of saving 16bit PNG files. Alpha for such files would be premultiplied, would be corrected with an upcoming alpha premul cleanup (it's not the only format which will output 16bit image with premul alpha).
This commit adds a support of saving 16bit PNG files. Alpha for such files would be premultiplied, would be corrected with an upcoming alpha premul cleanup (it's not the only format which will output 16bit image with premul alpha).