Pngcrush

Pngcrush is an open source optimizer for PNG (Portable Network Graphics) files.

Pngcrush can be run from a command-line in an MSDOS Window, or from a Linux or UNIX command-line.

What is new in this release:

• The bundled static libpng has been updated to version 1.6.9.

What is new in version 1.7.53:

• This version 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).

What is new in version 1.7.52:

• This version fixes initialization problems introduced in version 1.7.51, reinitializes settings before processing each file, and makes the "-reduce" option work properly.

What is new in version 1.7.50:

• This release implements the "-reduce" option properly.
• This examines the input file to see if the color type, bit depth, and palette length can be reduced without loss, and if there is an opaque alpha channel which can be removed.

What is new in version 1.7.41:

• This version fixes a bug introduced in version 1.7.39 which caused failure to write an output fil

What is new in version 1.7.35:

• Version 1.7.34 introduced a bug in which a file was opened for each trial compression but never written or closed.
• After a system-dependent number of trials, pngcrush was unable to open a file for the next trial and exited.
• This release fixes that bug.

What is new in version 1.7.33:

• This version only decodes PNG ancillary chunks during the final trial, and can be significantly faster when large ancillary chunks such as iCCP are present.

What is new in version 1.7.2:

• This version is built with libpng 1.2.40.
• There are some additional checks for the "verbose" setting when printing to make the "-s" option more silent.

What is new in version 1.7.0:

• Added APNG support.