在 python OpenCV 中调整和填充具有特定高度和宽度的图像会产生错误和不准确的结果

Question

基本上我有一个包含 180 张不同宽度和高度的图像的目录，我想将所有图像的大小调整为 1280 x 720 这是我的脚本运行

import sys
import os
import numpy as np
from os import walk
import cv2

# width to resize
width = int(sys.argv[1])
# height to resize
height = int(sys.argv[2])
# location of the input dataset
input_dir = sys.argv[3]
# location of the output dataset
out_dir = sys.argv[4]

if len(sys.argv) != 5:
    print("Please specify width, height, input directory and output directory.")
    sys.exit(0)

print("Working...")

# get all the pictures in directory
images = []
ext = (".jpeg", ".jpg", ".png")

for (dirpath, dirnames, filenames) in walk(input_dir):
  for filename in filenames:
        if filename.endswith(ext):
            images.append(os.path.join(dirpath, filename))

for image in images:
    img = cv2.imread(image, cv2.IMREAD_UNCHANGED)

    h, w = img.shape[:2]
    pad_bottom, pad_right = 0, 0
    ratio = w / h

if h > height or w > width:
        # shrinking image algorithm
  interp = cv2.INTER_AREA
else:
        # stretching image algorithm
        interp = cv2.INTER_CUBIC

w = width
h = round(w / ratio)
if h > height:
        h = height
        w = round(h * ratio)
pad_bottom = abs(height - h)
pad_right = abs(width - w)

scaled_img = cv2.resize(img, (w, h), interpolation=interp)
padded_img = cv2.copyMakeBorder(
        scaled_img,0,pad_bottom,0,pad_right,borderType=cv2.BORDER_CONSTANT,value=[0,0,0])

cv2.imwrite(os.path.join(out_dir, os.path.basename(image)), padded_img)


print("Completed!")

这里是命令 python2.7 $python resize_images.py 1280 720 '/home/train/images/bottle_1/' '/home/train/images/bottle_resize/' 这给了我错误工作... 追溯（最近一次通话）：文件 "resize_images.py"，第 46 行，位于 h = round(w / 比率) ZeroDivisionError：整数除法或模数为零

python3 $python3 resize_images.py 1280 720 '/home/train/images/bottle_1/' '/home/train/images/bottle_resize/' 的命令在这个命令的结果中它只调整一张图像的大小而没有给出任何错误或警告。如果有人可以帮助我，那么它没有调整图像大小和填充图像的原因可能是什么谢谢

Answer 1

正如我在上面的评论中所写，缩进是错误的：for image in images 循环以计算比率结束。然后你只处理 images 列表中的最后一张图像。上次与文件夹中的文件顺序无关，因为 walk returns 文件 任意顺序 。

以下是缩进正确的代码。它完美运行：

import sys
import os
import numpy as np
from os import walk
import cv2

# width to resize
width = int(sys.argv[1])
# height to resize
height = int(sys.argv[2])
# location of the input dataset
input_dir = sys.argv[3]
# location of the output dataset
out_dir = sys.argv[4]

if len(sys.argv) != 5:
    print("Please specify width, height, input directory and output directory.")
    sys.exit(0)

print("Working...")

# get all the pictures in directory
images = []
ext = (".jpeg", ".jpg", ".png")

for (dirpath, dirnames, filenames) in walk(input_dir):
  for filename in filenames:
        if filename.endswith(ext):
            images.append(os.path.join(dirpath, filename))
            print(filename)

for image in images:
    img = cv2.imread(image, cv2.IMREAD_UNCHANGED)

    h, w = img.shape[:2]
    pad_bottom, pad_right = 0, 0
    ratio = w / h

    if h > height or w > width:
        # shrinking image algorithm
        interp = cv2.INTER_AREA
    else:
        # stretching image algorithm
        interp = cv2.INTER_CUBIC

    w = width
    h = round(w / ratio)
    if h > height:
        h = height
        w = round(h * ratio)
    pad_bottom = abs(height - h)
    pad_right = abs(width - w)

    scaled_img = cv2.resize(img, (w, h), interpolation=interp)
    padded_img = cv2.copyMakeBorder(
        scaled_img,0,pad_bottom,0,pad_right,borderType=cv2.BORDER_CONSTANT,value=[0,0,0])

    cv2.imwrite(os.path.join(out_dir, os.path.basename(image)), padded_img)

print("Completed!")

在 python OpenCV 中调整和填充具有特定高度和宽度的图像会产生错误和不准确的结果

Resizing and Padding Image with specific height and width in python OpenCV gives errors and inaccurate results

python

opencv

python-2.7

python-3.x

cv2