CorePNG

• FOURCCs: PNG1
• Name: CorePNG
• Frame type: IP

This lossless codec is based on the PNG image format. Each frame can be encoded as-is (I frame), or can represent a delta from the previous frame (P frame). In both cases the data is compressed with in standard PNG format.

The codec was originally developed to compress subtitles.

The codec supports RGB[A] and YUV colorspaces: in RGB mode every frame is compresses as a PNG image; in YUV mode a frame is stored as 3 PNG images with order Y, U, V,

Here you can find the CorePNG codec website