免費線上 OTB 轉 PNM 轉換器

This format was created by Nokia for use in its proprietary phones. A bitmap image was used to transfer image files between devices over a wireless connection. It was mainly used when exchanging multimedia text messages that support inserting pictures.

A bitmap image in the Portable Any Map format that was originally developed for processing and storing several types of monochrome and color images without compression as well as grayscale images. Bitmap graphics data in a PNM file are stored using ASCII or binary structure.