Release Notes: This release eliminates many redundant file operations, resulting in a few percent speed increase.
Release Notes: Fixes a bug with reducing 16-bit images to 8-bit using the "-reduce" option. Restores calls to png_set_crc_action(), which had been removed from version 1.7.72 for some testing and inadvertently not restored. Adds code to fix/salvage PNG files with a "bad adaptive filter value" error. Avoids calculating CRC during compression trials except for the last trial, when the output is actually written.
Release Notes: The bundled static libpng has been updated to version 1.6.9.
Release Notes: This release fixes a bug with the new "-reduce" option which would remove the alpha channel even when it was not all-opaque.
Release Notes: This release fixes a bug introduced in 1.7.52 which caused the -reduce option to produce a tRNS chunk which had more entries than the PLTE chunk (which is invalid).
Release Notes: This release fixes initialization problems introduced in version 1.7.51, reinitializes settings before processing each file, and makes the "-reduce" option work properly.