Convert SR to PJPEG

The Sun Raster (SR) file extension, is a raster graphics file format developed by Sun Microsystems for use on their SunOS operating system. This format, which stores black-and-white, grayscale, and color bitmapped data, was widely used in UNIX-based systems and supported by various imaging applications. The Sun Raster format includes a header, an optional color map, and the bitmapped image data. Although it does not support transparency, it remains a simple and widely distributed bitmap format.

The PJPEG (Progressive JPEG) is a file extension for images that enhances the standard JPEG format by displaying images in successive waves of increasing detail, improving the user experience during slow network conditions. The JPEG stands for "Joint Photographic Experts Group", the organization that developed the standard in 1992. PJPEG is particularly useful for web applications, as it allows images to appear more quickly and progressively refine in quality, rather than loading from top to bottom like baseline JPEGs.