| Wireless Bitmap | |
|---|---|
| Filename extension |
.wbmp |
| Internet media type |
image/vnd.wap.wbmp |
| Developed by | WAP Forum |
| Type of format | Image file formats |
Wireless Application Protocol Bitmap Format (shortened to Wireless Bitmap and with file extension .wbmp) is a raster image file format optimized for early mobile computing devices.
WBMP images are monochrome black and white binary images in which a black pixel is denoted by 0 and a white pixel is denoted by 1. The simple pixel encoding and the small size of the file header mean that the file size is kept to a minimum, enabling fast transmission on slow networks.1
File format
| Field name | Field type | Size (in bytes) | Purpose |
|---|---|---|---|
| Type | uintvar | variable | Type of the image, and is 0 for monochrome bitmaps. |
| Fixed header | byte | 1 | Reserved. Always 0. |
| Width | uintvar | variable | Width of the image in pixels. |
| Height | uintvar | variable | Height of the image in pixels. |
| Data | byte array | variable | Data bytes arranged in rows – one bit per pixel. A black pixel is denoted by 0 and a white pixel is denoted by 1. The pixel order within a byte is MLP (most left pixel) = MSB (most significant bit). Where the row length is not divisible by 8, the row is 0-padded to the byte boundary. |
References
References
- "WAP Wireless Application Environment Specification Version 1.1" (PDF). wapforum.org. Wireless Application Protocol Forum Ltd. 24 May 1999. Retrieved 29 September 2024.