PBM to PALM Converter

PALM is a bitmap image format used by the Palm OS operating system, introduced in 1996 with the original Palm Pilot 1000. Palm bitmap files store raster images in formats optimized for the extremely constrained hardware of early Palm handheld devices — the original models featured a 160x160 pixel monochrome (2-shade) display, 128 KB of RAM, and a 16 MHz Motorola 68328 processor. The format evolved through several versions as Palm hardware improved: PalmOS 1.0 supported 1-bit monochrome, later versions added 2-bit (4 shade grayscale), 4-bit (16 shade), 8-bit (256 color), and eventually 16-bit (65536 color) direct color modes. Palm bitmaps use a simple header specifying width, height, row bytes, flags, and bit depth, followed by the pixel data which may use optional Scanline compression (a PackBits-like run-length encoding) or dense packing. The format also supports bitmap families — multiple versions of the same image at different bit depths bundled together, allowing the OS to select the best version for the current device's display capabilities. One advantage is the format's documentation of early mobile computing: Palm OS was the dominant handheld platform of the late 1990s and early 2000s, and Palm bitmap files from applications, games, and content of that era represent important artifacts of mobile computing history. The multi-depth bitmap family feature provides another notable design strength — a single resource could serve devices ranging from monochrome Palm Pilots to the 16-bit color Sony CLIE and Palm Tungsten. PALM bitmaps are supported by ImageMagick, pilot-link utilities, and Palm emulator tools.