旋转图片，空余部分补黑色，并将原坐标转换

#载入必要的模块
import os
from PIL import Image
from PIL import ImageDraw
import sys
import xlrd
import numpy
import math
import xlsxwriter

#输入
ExcelFile=xlrd.open_workbook(r‘.\标记信息.xlsx‘)
sheet=ExcelFile.sheet_by_index(0)
#输出
workbook = xlsxwriter.Workbook(‘./new/旋转后的标记信息.xlsx‘) #创建工作簿
worksheet = workbook.add_worksheet() #创建工作表

print(sheet.nrows)

for i in range(0,sheet.nrows):
    videoid=str(int(sheet.cell_value(i,0)))
    frameid=str(int(sheet.cell_value(i,1)))
    x1=int(sheet.cell_value(i,2))
    x2=int(sheet.cell_value(i,4))
    x3=int(sheet.cell_value(i,6))
    x4=int(sheet.cell_value(i,8))
    y1=int(sheet.cell_value(i,3))
    y2=int(sheet.cell_value(i,5))
    y3=int(sheet.cell_value(i,7))
    y4=int(sheet.cell_value(i,9))
    bookname=sheet.cell_value(i,10)

    #print([x1,y1,x2,y2,x4,y4,x3,y3,x1,y1])

    pic_fole_head =  Image.open(videoid+"_"+frameid+".jpg")
    width,height=pic_fole_head.size
    #print([width,height])

    #计算余弦值
    cosa=(y3-y1)/numpy.sqrt(numpy.power(x1-x3,2)+numpy.power(y1-y3,2))
    #计算需要选装的弧度
    rad=numpy.abs(numpy.arccos(cosa))
    #计算需要旋转的角度
    alpha=rad*180/math.pi
    #判断旋转的方向
    #并且计算旋转后的坐标
    if x3<x1:
        pic_fole_head=pic_fole_head.rotate(alpha,0,1)
        yy1=y1*numpy.cos(rad)+(width-x1)*numpy.sin(rad)
        xx1=x1*numpy.cos(rad)+y1*numpy.sin(rad)
        yy2=y2*numpy.cos(rad)+(width-x2)*numpy.sin(rad)
        xx2=x2*numpy.cos(rad)+y1*numpy.sin(rad)
        yy3=y3*numpy.cos(rad)+(width-x3)*numpy.sin(rad)
        xx3=x3*numpy.cos(rad)+y3*numpy.sin(rad)
        yy4=y4*numpy.cos(rad)+(width-x4)*numpy.sin(rad)
        xx4=x4*numpy.cos(rad)+y4*numpy.sin(rad)
    else:
        alpha=-alpha
        pic_fole_head=pic_fole_head.rotate(alpha,0,1)
        yy1=y1*numpy.cos(rad)+x1*numpy.sin(rad)
        xx1=x1*numpy.cos(rad)+(height-y1)*numpy.sin(rad)
        yy2=y2*numpy.cos(rad)+x2*numpy.sin(rad)
        xx2=x2*numpy.cos(rad)+(height-y2)*numpy.sin(rad)
        yy3=y3*numpy.cos(rad)+x3*numpy.sin(rad)
        xx3=x3*numpy.cos(rad)+(height-y3)*numpy.sin(rad)
        yy4=y4*numpy.cos(rad)+x4*numpy.sin(rad)
        xx4=x4*numpy.cos(rad)+(height-y4)*numpy.sin(rad)

    #print([xx1,yy1,xx2,yy2,xx4,yy4,xx3,yy3,xx1,yy1])
    #框出旋转后的书名，测试时用来验证
    #drawObject=ImageDraw.Draw(pic_fole_head)
    #drawObject.line([xx1,yy1,xx2,yy2,xx4,yy4,xx3,yy3,xx1,yy1],(0,5,255),5)

    #保存新结果
    worksheet.write(i, 0, int(videoid))
    worksheet.write(i, 1, int(frameid))
    worksheet.write(i, 2, int(xx1))
    worksheet.write(i, 3, int(yy1))
    worksheet.write(i, 4, int(xx2))
    worksheet.write(i, 5, int(yy2))
    worksheet.write(i, 6, int(xx3))
    worksheet.write(i, 7, int(yy3))
    worksheet.write(i, 8, int(xx4))
    worksheet.write(i, 9, int(yy4))
    worksheet.write(i, 10, bookname)
    worksheet.write(i, 11, videoid+"_"+frameid+"_"+str(i+1)+".png")
    #pic_fole_head.show()

    pic_fole_head.save("./new/"+videoid+"_"+frameid+"_"+str(i+1)+".jpg")
workbook.close()

本程序目的是：将标记的书名放到垂直方向

载入xlsx的部分因人而异，可以只看循环体中转换的步骤，坐标的转换是一个简单的几何关系。

最终的效果如下：

》》》》

原文地址：https://www.cnblogs.com/littleby/p/9770949.html