Convert APNG (Animated PNG) to SGI

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 SGI file extension stands for Silicon Graphics Image, a raster graphics file format developed by Silicon Graphics Inc. primarily for their IRIS workstations. This format, originating in the late 1980s, supports uncompressed and RLE-compressed data with up to 48-bit color (16 bits per channel for RGB) and an alpha channel. SGI files are widely utilized in 3D graphics, visualization, and high-end imaging due to their ability to store high-quality images and intricate details, making them an essential asset in professional graphics and animation industries.