Convert APNG (Animated PNG) to VIPS

Animated Portable Network Graphics (APNG) is an extension of the Portable Network Graphics (PNG) format designed to support animated images. Introduced in 2004, APNG allows for animated sequences while retaining backward compatibility with non-animated PNG files. This format is utilized for its lossless compression, making it ideal for web graphics where image quality is paramount. APNG files are widely used for animated icons, logos, and other elements that benefit from high-quality animations without the artifacts common in GIF files. Its concise, efficient structure makes it a preferred choice among developers and designers focused on optimizing web performance.

The VIPS (Virtual Image Processing System) file format, developed by the libvips library, is designed for high-performance image processing with low memory usage. It supports arbitrary metadata and is optimized for command-line operations. Although not widely supported by other programs, it serves as an efficient intermediate format for tasks like image inversion and gamma correction. The format includes a 64-byte header with basic fields such as image width and a set of band-interleaved scanlines for the image data.