All imaging file compressions can be divided into three basic types:
- 1D compression is compression in which the raster data is treated as one continuous data stream. Each byte read is compared to the previous byte. This compression method is not concerned with delineating lines of data.
- 2D compression can be thought of as "Differencing Compression", where the data stored is a representation of the differences in data values from previous data values. In 2D compression, the encoding of one line is determined by the contents of the previous line. This method of compression is best used for black-and-white images where the black pixels tend to fall into groups.
- 3D compression is data compression aimed at the 3D models and other geometric datasets used in computer graphics, virtual reality, video games, CAD/CAM, and many scientific, engineering, and medical applications. Existing 3D compression algorithms use both techniques adapted from the 1D and 2D cases (like wavelets, entropy coding, and predictive coding), and completely different approaches that take advantage of the properties of 3D surfaces (like Edgebreaker, Subdivision Surfaces, and triangle strips).
ImageGear supports the following compressions:
CCITT Group 3 Compression
CCITT Group 3 2D Compression
CCITT Group 4 Compression
Deflate Compression
Huffman Compression
JPEG Compressions
LZW (Lempel-Ziv-Welch) Compression
Packbits Compression
RLE Compression