dream-winter / bicubic-interpolation

Bicubic interpolation for images (Python)

Bicubic-interpolation

This repository is for simple implementation of 'Bicubic-interpolation for images' (Python3).

Table of contents

• Formulation
• Example
• Requirement
• Installation
• Usage
• Reference
• Author

Formulation

• Interpolation kernel [1]
  

• Interpolation
  Use the values of 16 pixels around the new pixel dst(x,y) [1][2]. (x,y) shows the location of pixels.
  Here, f means the values of pixels. x1, x2, x3, x4 are the distance of x direction from new pixel to near 16 pixels. y1, ... are the distance of y direction.

Example

• Upscale input image 2 times (ratio = 2)
  The 'butterfly' image is from [3].
  
  ↑ Input image (256x256)
  
  ↑ Output image (512x512)

Requirement

• Python 3.5.2 or more

Installation

$ git clone https://github.com/rootpine/Bicubic-interpolation.git

Usage

1. $ python3 bicubic.py

Reference

1. R. Keys, "Cubic convolution interpolation for digital image processing," in IEEE Transactions on Acoustics, Speech, and Signal Processing, vol. 29, no. 6, pp. 1153-1160, December 1981. URL: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=1163711&isnumber=26156
2. 奥富正敏ら, "ディジタル画像処理[改定新版]", CG-ARTS協会, pp. 170-171, 2016.
3. M. Bevilacqua, A. Roumy, C. Guillemot and ML. Alberi, "Low-Complexity Single-Image Super-Resolution based on Nonnegative Neighbor Embedding",BMVC 2012.
4. https://github.com/yunabe/codelab/blob/master/misc/terminal_progressbar/progress.py to show the progress.

Author

@rootpine