A Design of Optimized Colour Image Interpolation Algorithm Based on Edge Gradient

An improved hibbard interpolation algorithm based on edge gradient feature detection using Sobel operator

“…For the problem that too little information is utilized in calculating the gradient, Sobel operator [6][7] is introduced to calculate the gradients to solve it. To solve the problem of interpolation edge direction selection [8][9], this paper calculate the interpolation weights of the two directions according to the relative magnitudes of the gradients in the horizontal and vertical directions.…”

Image Interpolation with Regional Gradient Estimation

“…Many image scaling methods have been proposed recently , and these methods can be divided into two categories, one being sample-based super-resolution reconstruction [4][5][6][7][8][9][10][11][12] and the other being sample-free-based interpolation [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28]. The main difference between the two is that sample-free-based interpolation uses mathematical methods to estimate pixels directly based on the known pixels, whereas super-resolution reconstruction requires training samples to establish a mapping relationship between low-resolution images and high-resolution images before it can use image block-matching and replacement to complete the interpolation.…”

“…Nonlinear interpolation methods mainly include methods based on wavelet transform [25][26][27][28] and methods based on edge information [13][14][15][16][17][18][19][20][21][22][23][24]. The interpolation is based on wavelet transform: first, wavelet transform is performed on the image; next, the classical image interpolation method is used to interpolate the frequency domain coefficients; then, threshold processing is performed to obtain the required interpolation image.…”