图片变形（shear，scaling，rotation，flip，translation）
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2020-12-21
07:46:38
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图片变形（图片变形（shear，，scaling，，rotation，，flip，，translation））
# -*- coding: utf-8 -*-
"""
Created on Tue Apr 21 16:07:47 2020
@author: Administrator
"""
import numpy as np
import cv2
import os
from matplotlib import pyplot as plt
DEFAULT_PRNG = np.random
#定义图片转换参数
class TransformParameters:
def __init__(
self,
fill_mode = 'nearest',
interpolation = 'linear',
cval = 0,
relative_translation = True,
):
self.fill_mode = fill_mode
self.cval = cval
self.interpolation = interpolation
self.relative_translation = relative_translation
def cvBorderMode(self):
if self.fill_mode == 'constant':
return cv2.BORDER_CONSTANT
if self.fill_mode == 'nearest':
return cv2.BORDER_REPLICATE
if self.fill_mode == 'reflect':
return cv2.BORDER_REFLECT101
if self.fill_mode == 'wrap':
return cv2.BORDER_WRAP
def cvInterpolation(self):
if self.interpolation == 'nearest': #最近邻插值
return cv2.INTER_NEAREST
if self.interpolation == 'linear': #双线性插值，适合放大图片
return cv2.INTER_LINEAR
if self.interpolation == 'cubic': #4x4像素邻域的双三次插值，适合放大图片
return cv2.INTER_CUBIC
if self.interpolation == 'area': #局部像素重采样，适合缩小图片
return cv2.INTER_AREA
if self.interpolation == 'lanczos4':
return cv2.INTER_LANCZOS4 #8x8像素插值法
#随机转动一定角度
def random_rotation(min, max, prng=DEFAULT_PRNG):
angle = prng.uniform(min, max)
rotation_reslut = np.array([
[np.cos(angle), -np.sin(angle),0],
[np.sin(angle), np.cos(angle), 0],
[0, 0, 1] ])
return rotation_reslut
#随机平移
def random_translation(min, max, prng=DEFAULT_PRNG):
min = np.array(min)
max = np.array(max)
assert min.shape == max.shape
assert len(min.shape) == 1
translation = prng.uniform(min, max)
translation_result = np.array([
[1, 0, translation[0]],
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