OrbConvert converts your image files online. Amongst many others, we support PNG, JPG, JPEG, WEBP, GIF, SVG and TIFF. You can use the options to control image resolution, quality and file size.
From
Portable GrayMap
The Netpbm grey-scale format — one channel, uncompressed. Colour information is discarded, not converted.
All PGM conversionsTo
Wireless BitMap
A one-bit format designed for early mobile devices and WAP pages. Every pixel is black or white, and colour is discarded.
All WBMP conversions