What form of linearization are you referring too? A gamma curve on rendering for colour space adjustment/display compensation?
AFAIK The gamma curve is left straight as there are so many different HDMI displays that could be plugged in, and each will have subtly different characteristics.
If rendering a YUV image, then as HDMI is normally driven as RGB there is a colourspace conversion. video_render does support selection of various colour conversion matrices (see OMX_COLORSPACETYPE
for use with OMX_IndexParamColorSpace)
The image will be resized to fill the screen if necessary. If the source image is the same size as the display then it should be a 1:1 pixel mapping and no resizing filter used. If they differ then it'll use a filter.
Software Engineer at Raspberry Pi Trading. Views expressed are still personal views.
I'm not interested in doing contracts for bespoke functionality - please don't ask.