Image Rotation(Python)

 

import cv2 as cv
import numpy as np
import math

roi = cv.imread('picture6.jpg')

angle = 10.0

angle = angle* math.pi/180

normal_rotation = np.zeros((roi.shape[0],roi.shape[1],3),dtype=np.uint8)
normal_interpolation = np.zeros((roi.shape[0],roi.shape[1],3),dtype=np.uint8)
bilinear_interpolation = np.zeros((roi.shape[0],roi.shape[1],3),dtype=np.uint8)

for i in range(roi.shape[0]):
    for j in range(roi.shape[1]):
        for k in range(3):
            cy = roi.shape[0] // 2
            cx = roi.shape[1] // 2
            y = i - cy
            x = j - cx
            newY = y * math.cos(angle) - x * math.sin(angle) + cy
            newX = y * math.sin(angle) + x * math.cos(angle) + cx
            newY = round(newY)
            newX = round(newX)
            if newX >=0 and newX < roi.shape[1] and newY >=0 and newY < roi.shape[0]:
                normal_rotation.itemset(newY,newX,k,roi.item(i,j,k))

for i in range(roi.shape[0]):
    for j in range(roi.shape[1]):
        for k in range(3):
            cy = roi.shape[0] // 2
            cx = roi.shape[1] // 2
            y = i - cy
            x = j - cx
            newY = y * math.cos(angle) + x * math.sin(angle) + cy
            newX = y * -math.sin(angle) + x * math.cos(angle) + cx
            newY = round(newY)
            newX = round(newX)
            if newX >=0 and newX < roi.shape[1] and newY >=0 and newY < roi.shape[0]:
                normal_interpolation.itemset(i,j,k,roi.item(newY,newX,k))

for i in range(roi.shape[0]):
    for j in range(roi.shape[1]):
        for k in range(3):
            cy = roi.shape[0] // 2
            cx = roi.shape[1] // 2
            y = i - cy
            x = j - cx
            newY = y * math.cos(angle) + x * math.sin(angle) + cy
            newX = y * -math.sin(angle) + x * math.cos(angle) + cx
            alpha = 1 - (newX-math.floor(newX))
            beta = 1 - (newY-math.floor(newY))
            newX = round(newX)
            newY = round(newY)
            if newX >=0 and newX < roi.shape[1]-1 and newY >=0 and newY < roi.shape[0]-1:
                f1 = (1-alpha)*roi.item(newY,newX,k)+alpha*roi.item(newY,newX+1,k)
                f2 = (1-alpha)*roi.item(newY+1,newX,k)+alpha*roi.item(newY+1,newX+1,k)
                f3 = (1-beta)*f1+beta*f2
                bilinear_interpolation.itemset(i,j,k,int(f3))

cv.imshow('origin',roi)
cv.imshow('rotation_normal',normal_rotation)
cv.imshow('interpolation_normal',normal_interpolation)
cv.imshow('interpolation_bilinear',bilinear_interpolation)
cv.waitKey(0)
cv.destoryAllWindows()

파이썬 opencv라이브러리를 통해 구현한 이미지 회전 프로그램.

공부의 목적으로 직접 픽셀에 접근하여 회전하게 하였다.

출력되는 사진은 원본, 일반회전, 최근접이웃, 양선형보간법 순으로 되어있다.