Pure ruby library for read/write, chunk-level access to PNG files
Description
This pure Ruby library can read and write PNG images without depending on
an external image library, like RMagick. It tries to be memory efficient and
reasonably fast.
It supports reading and writing all PNG variants that are defined in the
specification, with one limitation: only 8-bit color depth is supported. It
supports all transparency, interlacing and filtering options the PNG
specifications allows. It can also read and write textual metadata from PNG
files. Low-level read/write access to PNG chunks is also possible.
This library supports simple drawing on the image canvas and simple operations
like alpha composition and cropping. Finally, it can import from and export to
RMagick for interoperability.
