PS/PDF: Set image Interpolation flag

If the filter mode is anything other than DEFAILT, FAST or NEAREST set the
Interpolate flag in the image dictionary so that a smoothing filter is
applied when rasterising the vector file.

As we have no control over the implementation of the Interpolate filter
(the PS/PDF specifications leave it undefined) we need to capture the
output of poppler/GS and update our reference images. (For a couple of
tests, the filtering is irrelevant so for those we set the filter to
NEAREST.)

Note that GhostScript's Interpolate filter does not work on rotated images
(and a variety of other transformations) so several of the PS reference
images have use nearest-neighbour sampling instead of a bilinear filter.

0 files changed, 0 insertions, 0 deletions