libjpeg rounds up on shrink-on-load. In some cases this can leave a dark
line along the right and bottom edge, since it only contains (for
example) 1/4 of a pixel of data.
This change adds a crop after jpeg load so that only complete pixels are
output.
See https://github.com/lovell/sharp/issues/1185
If O_TNMPFILE is available, use it. This is a linux extension that
creates an unlinked file, so it'll be closed by the system when the last
associated fd is closed.
see https://github.com/jcupitt/libvips/pull/930
TODO
- more code sharing with pdfload.c, eg. vips_foreign_load_pdf_is_a_buffer()
and get_flags etc.
- could share the page layout code too
- make pdf.c with base stuff in?
- what about filename encodings
- test transparency
- new_from_buffer needs doing
Before, they could make B_W for one-band output. This caused problems
with (for example) two black image bandjoined: the second band then
looked like an alpha to hasalpha() and enabled premultiply/unpremultiply
for operations like affine.
Now, it's always MULTIBAND. This is the generic multiband image type, so
you don't get any unexpected alpha handling.
The result of hasalpha is used to turn on things like
premultiplication, so we should be rather conservative
about when we signal this. We don't want to premultiply
things that should not be premultiplied.
Check Type as well as bands.
See: https://github.com/jcupitt/libvips/issues/918
libpng has started throwing hard errors if the profile does not match
the image -- this can happen all the time with perofiles inherited from
images that have been processed.
Test profiles before save and drop them (with a warning) if they are
incompatible with the image.
vips__get_bytes() used to fail if the file was too small for the
allocated buffer, which was a problem for svg, since files can be extremely
small.
This change makes vips__get_bytes() return the number of bytes read, so
the is_a testers can work on files smaller than the max header size.
