Support loading 16-bit PNGs

[stevengoldberg]

Description

It looks like when I load a 16-bit PNG into an SkImage (via the useImage hook) the result is still an 8-bit PNG: image.getImageInfo().colorType is 4, which corresponds to RGBA_8888.

Is it possible to support 16-bit PNGs in SkImage?

[wcandillon]

this is an interesting question. If we load the image and do a readPixels on it, no Skia surface (texture format) is involved, I would like to investigate it this further.
readPixel has an image info parameter, if you set the right color format, could it be that you get the expected decoded bytes?
I have a branch where you can set an Skia surface to be 16bits and I'm wondering if providing the readPixel(correct image info) on that surface return the appropriate information.