now there's the new jpg folder, which is nice, but it's jpg, so no transparency channel, which a png would have. now i could mask the jpg sequence of course with another jpg sequence, but as far as i remember, having one with an alpha channel runs faster, than one without one and a mask instead. soo.. would a png-folder be a legitimate feature request, or did i oversee something?
I think so. It depends on each situation, but I did run some tests with .png sequences a while ago, and the maximum speed was several times slower than with .jpg's. For .jpg's, the file sizes are smaller, and most of the decoding work is done with hardware acceleration on the CPU/GPU. For .png's , no hardware acceleration of any kind can be used.
One thing you can do to make a .jpg mask even faster is save it as grayscale so it's 1/3 of the size. It will be read from disk and decoded more efficiently.
