Image Conversion source code

Raw Digital Photo Decoding in Linux
List of Java libraries to read and write pixel image files
Additional material: Visualization and code ppm format
pbmplus - image file format conversion package
Convert a BMP Image to a JPEG using victor library
24 to 16 bitmap converter
icculus.org Subversion Repositories - markup - quake3: trunk/code/renderer/tr_image.c
Raster Data Tutorial (24-Bit)
DataCompression.info - Source Code
[15] Freely available source code for JPEG
YOV408 Programming Resources - Code Spotlight - JPEG Encoder Source

Code
Basics: Understanding Resolution
data compression
BMP image format
Code for reading bmp files and possible conversion to jpeg
Independent JPEG Group
JpegFile - free JPG (and BMP) reading and writing code.
My Downloads for image processing