More sophisticated defaulting which helps significantly for some files along
with code to make it easier to control the compression defaults and to make the
settings honor the API calls the application makes (previously low windowBits
settings would get reset to higher values.)
Signed-off-by: John Bowler <jbowler@acm.org>
This implements an API and provides a number of assist macros to allow an
application which uses the simplified API write to bypass stdio and write
directly to memory.
It also includes some warnings (png.h) and some check code to detect *possible*
overflow in the ROW_STRIDE and simplified image SIZE macros. This disallows
image width/height/format that *might* overflow. A quiet API change that limits
in-memory image size (uncompressed) to less that 4GByte and image row size
(stride) to less than 2GByte.
Signed-off-by: John Bowler <jbowler@acm.org>
The filter selection options are made more intuitive (IMO, but I am not an
Intuitive User). Dummy code added for methodical filter selection.
Signed-off-by: John Bowler <jbowler@acm.org>
This implements the heuristic part of filter selction, the methodic testing
approach is still not implemented. png_set_option methods are incomplete.
Signed-off-by: John Bowler <jbowler@acm.org>
Now that the code works consistently so that these just switch off the support
for having libpng do the interlace/deinterlace the old names make more sense,
restoring them avoids cruft in the configuration file and avoids an unnecessary
version specific change.
Signed-off-by: John Bowler <jbowler@acm.org>
This implements a new chunk parse implementation that can be shared, it
is currently shared by the progressive reader and the sequential one
(not, yet, the writer).
The patch also implements shared transform handling that is used
throughout.
Signed-off-by: John Bowler <jbowler@acm.org>
compiled library size. It never worked properly and as far as we can
tell, no one uses it. The png_set_filter_heuristics() and
png_set_filter_heuristics_fixed() APIs are retained but deprecated.
