Convert APNG (Animated PNG) to OTB

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 OTB (Over The Air Bitmap) file extension, developed by Nokia, is used for transmitting black and white bitmap images between mobile phones, particularly Nokia and Siemens models. These images, with a maximum resolution of 255x255 pixels, are often sent via SMS in either hexadecimal text or binary format. Historically, OTB files were popular in the early days of mobile communication for sending simple graphics, icons, and wallpapers when data transmission speeds were limited.