can handle.

Reverted previous attempt to allow gAMA and sRGB non-support with the
simplified API.

chunk length written by libpng-1.6.0 and 1.6.1.

    (Flavio Medeiros).

a flag to change default. In 1.6.0 when the simplified API was used
to produce color-mapped output from an input image with no gamma
information the gamma assumed for the input could be different from
that assumed for non-color-mapped output.  In particular 16-bit depth
input files were assumed to be sRGB encoded, whereas in the 'direct'
case they were assumed to have linear data.  This was an error.  The
fix makes the simplified API treat all input files the same way and
adds a new flag to the png_image::flags member to allow the
application/user to specify that 16-bit files contain sRGB data
rather than the default linear.
Fixed bugs in the pngpixel and makepng test programs.

Folded some long lines.

png_set_* APIs

two test programs to generate and test a PNG which should have the problem.

color. This is useful for debugging pngstest color inaccuracy reports.

READ_GAMMA.  Prior to 1.6.0 switching off READ_GAMMA did unpredictable things
to the interfaces that use it (specifically, png_do_background in 1.4 would
simply display composite for grayscale images but do composition
with the incorrect arithmetic for color ones). In 1.6 the semantic
of -DPNG_NO_READ_GAMMA is changed to simply disable any interface that
depends on it; this obliges people who set it to consider whether they
really want it off if they happen to use any of the interfaces in
question (typically most users who disable it won't).

with zlib-1.2.7

option to pngtest. The "--relaxed" option turns off the benign errors that are
enabled by default in pre-RC builds. makepng can now write ICC profiles
where the length has not been extended to a multiple of 4, and pngtest
now intercepts all libpng errors, allowing the previously-introduced
"--strict test" on no warnings to actually work.

    contrib/libtests/makepng: corrected 'rgb' and 'gray' cases.  profile_error
    messages could be truncated; made a correct buffer size calculation and
    adjusted pngerror.c appropriately. png_icc_check_* checking improved;
    changed the functions to receive the correct color type of the PNG on read
    or write and check that it matches the color space of the profile (despite
    what the comments said before, there is danger in assuming the app will
    cope correctly with an RGB profile on a grayscale image and, since it
    violates the PNG spec, allowing it is certain to produce inconsistent
    app behavior and might even cause app crashes.) Check that profiles
    contain the tags needed to process the PNG (tags all required by the ICC
    spec). Removed unused PNG_STATIC from pngpriv.h.

png_handle_unknown() when SAVE support is absent.  Moved the shell test
scripts for contrib/libtests from the libpng top directory to contrib/libtests.
png_handle_unknown() must always read or skip the chunk, if
SAVE_UNKNOWN_CHUNKS is turned off *and* the application does not set
a user callback an unknown chunk will not be read, leading to a read
error, which was revealed by the "tunknown" test.

control of the unknown handling, corrects the pre-existing bug where
the per-chunk 'keep' setting is ignored and makes it possible to skip
IDAT chunks in the sequential reader (broken in earlier 1.6 versions).
There is a new test program, test-unknown.c, which is a work in progress
(not currently part of the test suite).  Comments in the header files now
explain how the unknown handling works.

support.  Now "make check" will succeed even if libpng is compiled with
-DPNG_NO_READ or -DPNG_NO_WRITE.  The tests performed are reduced, but the
basic reading and writing of a PNG file is always tested by one or more of
the tests.