Upscaling of an image refers to enlarging the size of an image.

图像放大是指放大图像的大小。

In this program, we will be using two functions of OpenCV-python (cv2) module.. let's see their syntax and descriptions first

在此程序中，我们将使用OpenCV-python(cv2)模块的两个函数。.让我们首先查看它们的语法和描述。

1) imread():

It takes an absolute path/relative path of your image file as an argument and returns its corresponding image matrix.

1)imread()：

它以图像文件的绝对路径/相对路径作为参数，并返回其对应的图像矩阵。

If flag value is:

如果标志值为：

• 1: Loads a color image.

  1 ：加载彩色图像。

• 0: Loads image in grayscale mode.

  0 ：以灰度模式加载图像。

• -1: Loads image as such including alpha channel.

  -1 ：加载图像，包括alpha通道。

If the flag value is not given then show the original image, which path is given.

如果未给出标志值，则显示原始图像，并给出哪个路径。

2) imshow():

It takes window name and image matrix as an argument in order to display an image in a display window with a specified window name.

2)imshow()：

它以窗口名称和图像矩阵为参数，以便在具有指定窗口名称的显示窗口中显示图像。

Also In this program, we will be using one function of numpy module.

同样在此程序中，我们将使用numpy模块的一个功能。

median(): It takes array and returns the median of the array .

平均()：它接受array并返回array的中位数。

Also, in this program we are using the concept of array slicing

另外，在此程序中，我们使用数组切片的概念

Let, A is 1-d array:

A[start:stop:step]

设A为一维数组：

A [开始：停止：步骤]

1. start: Starting number of the sequence.

   start：序列的起始编号。

2. stop: Generate numbers up to, but not including this number.

   停止：生成不超过此数字的数字，但不包括此数字。

3. step: Difference between each number in the sequence.

   步骤：序列中每个数字之间的差。

Example:

例：

A = [1,2,3,4,5,6,7,8,9,10]    print(A[ 1: 5])    Output:    [2,3,4,5]

用于在Python中放大灰度图像的Python程序 (Python program for upscaling the grayscale image in Python)

# open-cv library is installed as cv2 in python# import cv2 library into this programimport cv2# import numpy as np nameimport numpy as np# read an image using imread() function of cv2# we have to  pass only the path of the imageimg = cv2.imread(r'C:/Users/user/Desktop/pic6.jpg',0)# displaying the image using imshow() function of cv2# In this : 1st argument is name of the frame# 2nd argument is the image matrixcv2.imshow('original image',img)# upscaling code# Upscaling the image x,y times along row and columnx,y = 2, 2# here image is of class 'uint8', the range of values  # that each colour component can have is [0 - 255]# create a zero matrix of order of x,y times# of previous image of 3-dimensionsupscale_img = np.zeros((x*img.shape[0],y*img.shape[1]),np.uint8)i, m = 0, 0while m < img.shape[0] :    j, n = 0, 0    while n < img.shape[1]:        # We assign pixel value from original image matrix to the        # new upscaling image matrix in alternate rows and columns        upscale_img[i, j] = img[m, n]        # increment j by y times        j += y        # increment n by one        n += 1    # increment m by one    m += 1    # increment i by x times    i += x   cv2.imshow('upscaling image',upscale_img)

Output

输出量

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