Pack/unpack pixels.
The "p2p" library implements conversion between packed and planar image formats. A packed format is any memory layout that stores more than one image component ("plane") in a single array. For example, the common ARGB format stores pixels as an array of DWORDs holding all components for each pixel. In contrast, a planar format stores each image component in its own array.
libp2p is intended for embedding within other libraries and applications. The header "p2p.h" contains a template library for generating packing and unpacking routines, which can be used to instantiate functions for various pixel formats. "v210.cpp" holds a special-case implementation for the Apple ProRes "v210" format. "p2p_api.h" and "p2p_api.cpp" implement a "C" wrapper for a fixed set of commonly encountered packed formats. If the "C" wrapper is used from another library, a method to control symbol visibility should be used to prevent name conflicts with other, potentially incompatible, instances of libp2p.