MatHTJ2K

MatHTJ2K is an implementation of JPEG 2000 Part 1 and Part 15 (High-Throughput JPEG 2000)

# Summary

High Throughput JPEG 2000 (HTJ2K) is a new part of JPEG 2000 standard. The purpose of MatHTJ2K is to help a person who wants to develop an HTJ2K-based image compression system to understand the algorithms defined in HTJ2K. You can find more detailed information about HTJ2K on https://htj2k.com.

What you can do with MatHTJ2K are:

- to compress an image into a codestream which is compliant with JPEG 2000 Part 1 or Part 15.
- to decompress a codestream which is compliant with JPEG 2000 Part 1 or Part 15 into an image.
- to read/to write .jp2 and .jph file.

# Prerequisites

- MATLAB 2018b or higher with Image processing toolbox (older version may be fine, but not tested.)
- to use MEX version of block-coder, MATLAB Coder is required.

# Install

Type the following command in the command window:

`addpath(genpath('source'))`

If you want to save path settings for future session, use `savepath` command.

# Usage

## MEX functions (optional)

To generate MEX functions, type `generate_MEX_files` in the command window.

## Encoding

To compress an image stored in array "IMG", type the following command in the command window:

`encode_HTJ2K(filename, IMG, MEXflag)`

`MEXflag` should be `true` if you want to use MEX version of block-coder.

### available options to encoder

please see help (type `help encode_HTJ2K` in the command window)

## Decoding

To decompress a codestream, jp2 or jph, type the following command in the command window:

`[output composited_output] = decode_HTJ2K(filename, MEXflag, reduce_NL)`

`MEXflag` should be `true` if you want to use MEX version of block-coder.

`reduce_NL` is number of DWT resolution to be reduced from that of the original codestream/file.

For further details, please see help encode_HTJ2K/decode_HTJ2K.