Convert sixel to otb

What is the difference between .sixel and .otb?

Description: Created by Digital Equipment Corporation (DEC), SIXEL is a bitmap image format in an escaped sequence (seen as six pixels high and one pixel wide). You have to convert it into a more accessible format if you don’t have a DEC terminal to view it.; The OTB (Nokia Over The Air Bitmap Image) file format is a type of image file developed for use on Nokia mobile devices. These files are specifically optimized for efficient transmission and display on Nokia phones, particularly older models. The OTB format is designed to be compact to facilitate over-the-air (OTA) transmission, which was an essential feature in the era of limited bandwidth and data transfer capabilities. The format supports monochrome graphics, making it suitable for simple images like icons and logos.