hackfin/nhwcodec repository overview

⁠Preface

This is an experimental branch as an attempt to restructure the code for more understanding by non-insiders. It is considered highly unstable. Do not use as reference. See Docker notes below for testing against a working reference.

⁠NHW Image Codec

A Next-Generation Free Open-Source Image Compression Codec

The NHW codec is an experimental codec that compresses for now 512x512 bitmap 24bit color images using notably a wavelet transform.

The NHW codec presents some innovations and a unique approach: more image neatness/sharpness, and aims to be competitive with current codecs like for example x265 (HEVC), Google WebP,...

Another advantage of the NHW codec is that it has a high speed, making it suitable for mobile, embedded devices.

⁠How to compile?

For Windows: gcc *.c -O3 -o nhw_en/decoder.exe

For Linux: see Makefiles in sub folders

To encode an image (512x512 bitmap color image for now): nhw_encoder.exe imagename.png

encoder options: quality settings: -h1..3 or -l1..19

⁠Windows:

example: nhw_encoder.exe imagename.png -l3

To decode: nhw_decoder.exe imagename.nhw

⁠Linux:

⁠Docker container:

Docker containers have been proved to be an optimum way for testing the code and checking against reference implementations.

A Dockerfile is provided in docker/Dockerfile.

To build this container, you may use a local installation of the Docker Toolbox on Windows or the corresponding package on a standard Linux distribution.

Commands to build the container (inside docker/):

Start the container:

Inside the container:

Now you should have all prerequisites installed.

1. Build Codec:

1. Run tests/batch conversion of test images in ~/work: