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CHIP.c
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LICENSE.txt
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README.md
README.md
 
 

README.md

Extended Hexagonal Image Processing Framework HIP in C (CHIP)

This is the Extended Hexagonal Image Processing Framework HIP in C (CHIP) of this project.

It optimizes and extends the Hexagonal Image Processing Framework HIP by Lee Middleton and Jayanthi Sivaswamy [1] with:

  • Implementations for the hexagonal discrete cosine transform (H-DCT) [2],

  • hexagonal image quantization,

  • hexagonal filters (i.e., low-/high-pass, un-/blurring, and Lanczos filters) [3], and

  • hexagonal scaling, as well as

  • Lookup tables (LUT) for a more efficient processing.

[1] Middleton, L., & Sivaswamy, J. (2005). Hexagonal image processing: A practical approach. Springer Science & Business Media.

[2] Azam, M., Anjum, M. A., & Javed, M. Y. (2010, February). Discrete cosine transform (DCT) based face recognition in hexagonal images. In 2010 The 2nd International Conference on Computer and Automation Engineering (ICCAE) (Vol. 2, pp. 474-479). IEEE.

[3] James D. Allen (2003). Filter Banks for Images on Hexagonal Grid. Signal Solutions, Unltd. https://fabpedigree.com/james/hexim1.htm

Installation

Dependencies

sudo apt-get install libepoxy-dev libgtk-3-dev libxml2-utils libjpeg-dev libpng-dev libtiff-dev

wget https://github.com/ImageMagick/ImageMagick/archive/refs/tags/7.1.1-0.tar.gz && \
	tar xzf 7.1.1-0.tar.gz && \
	cd ImageMagick-7.1.1-0 && \
	./configure && \
	make

sudo make install && sudo ldconfig /usr/local/lib && cd ..

CHIP

Standalone

make CHIP

Usage

./CHIP

Usage: ./CHIP \
           <input image filename> \
           <title of the output> \
           <Hexarray size in order (number of pixels = 7^order) (1-7)> \
           <image transformation (0-3): bilinear / bicubic / Lanczos / B-spline interpolation> \
           <hexagonal-to-square image transformation (h2s) (>0.0): interpolation radius> \
           <hexagonal-to-square image transformation (h2s) (>0): number of pthreads> \
           <square-to-hexagonal image transformation (s2h) (>0.0): scaling factor> \
           <hexagonal-to-square image transformation (h2s) (>0.0): scaling factor> \
           <hexagonal DCT (0|2|5): disabled / with Hexarray order 1 / with Hexarray order 2> \
           <hexagonal DCT mode (0-5): H-DCT / DCT-H (only N = 5) / Log Space 1D-DCT-H | 1D-DCT-H (3)> \
           <hexagonal quantization (1-99): quality factor> \
           <hexagonal fitlers (0-6): blurring / unblurring / low-pass / high-pass filters (4)> \
           <hexagonal scaling (0-4): downscaling based on Hexarray order (HIP) (2) / own up- / own downscaling>

Test

make test

License

MIT License