All storage formats have other values for the Coding
field. This
release supports only IM_CODING_LABQ
format.
IM_CODING_LABQ
stores ,
and
for each pixel,
with 10 bits for
and 11 bits for each of
and
. These
32 bits are packed into 4 bytes, with the most significant 8 bits of each
value in the first 3 bytes, and the left-over bits packed into the final
byte as 2:3:3.
This format is a little awkward to process. Some VIPS functions can work
directly on IM_CODING_LABQ
images (im_extract()
, for example),
but most will require you to unpack the image to one of the computation
formats (for example with im_LabQ2Lab()
) first.