WIP QOI image format implemented in python. This is a python practice project for myself to learn qoi format and try to write an python library.

Useful resources

• qoi image format
• qoir format, an fast, simple, lossless image format inspired by qoi format.
• python bitwise operation tutorial.
• introduction video of png by Reduciable which explain the working mechanism of qoi format.

Test cases

# make sure you have the dependencies installed
$python3 test_qoi.py
$tree --du -h ./output/
[ 13M]  .
├── [374K]  test.jpg
├── [5.9M]  test.npy
├── [3.5M]  test.png
└── [3.5M]  test.qoi

  13M used in 1 directory, 4 files

Artist

Test image from @video

Prerequisite library

conda install numpy matplotlib

todo:

• find a way to implement sign bit in python
• check pack_qoi_op_diff and pack_qoi_op_luma function
• check qoi end marker when reaching the last pixel
• support rgba images
• add error checking when pixel value overflows
• make it python library
• move qoi_decode and qoi_encode into qoi.py