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
Radiance HDR
Stores a wide brightness range in the compact RGBE encoding, common in 3D lighting and environment maps. It carries no transparency.
All HDR conversions