python圖檔切割與合并

• • 1.tif圖檔切割為jpg
  • 2.圖檔合并

1.tif圖檔切割為jpg

• 将圖檔切割為1024大小的小圖檔
• 大小不夠1024的，填充為黑色

  import os
  import numpy as np
  import cv2 as cv
  import PIL.Image as Image
  
  
  def cutting(img_path, data_path,image_name, clip_path):
  
      """
  
      :param img_path: 圖檔檔案夾
      :param data_path: 資料檔案夾
      :param image_name: 切割原始圖檔名
      :param clip_path: 切割圖檔儲存路徑
      :return:
      """
      img_size = 1024
      n, m, max_n = 0, 0, 0
      img = cv.imread(os.path.join(img_path, image_name), 1)
      clip_img_path = os.path.join(data_path, 'clip', clip_path)
      if not os.path.exists(clip_img_path):
          os.makedirs(clip_img_path)
      h, w = img.shape[0], img.shape[1]
      # 圖檔切割
      for i in range(0, h, img_size):
          img_h = (h % img_size) if (i + img_size) > h else 1024
          for j in range(0, w, img_size):
              max_n = n if max_n <= n else max_n
              end_i, end_j = min(h, i + img_size), min(w, j + img_size)
              cropped = img[i:end_i, j:end_j]
              img_w = (w % img_size) if (j + img_size) > w else 1024
              img_orig = Image.fromarray(cv.cvtColor(cropped, cv.COLOR_BGR2RGB)) # bgr 轉 rgb
              to_image = Image.new('RGB', (img_size, img_size))  # 建立1024大小圖檔
              to_image.paste(img_orig, (0, 0))
              if img_w != 1024:  # 寬度填充
                  img_w_new = np.zeros(shape=((img_size - img_w), img_h, 3), dtype=np.uint8)
                  img_w_new = Image.fromarray(img_w_new)
                  to_image.paste(img_w_new, (img_w, 0))
                  if img_h != 1024:  # 寬度填充 and 高度填充
                      img_h_new = np.zeros(shape=(img_size, (img_size - img_h), 3), dtype=np.uint8)
                      img_h_new = Image.fromarray(img_h_new)
                      to_image.paste(img_h_new, (0, img_h))
                  to_image.save(clip_img_path + '/' + str(m) + '_' + str(n) + ".jpg")
              elif img_w == 1024 and img_h != 1024:  # 隻填充高度
                  img_h_new = np.zeros(shape=(img_size, (img_size - img_h), 3), dtype=np.uint8)
                  img_h_new = Image.fromarray(img_h_new)
                  to_image.paste(img_h_new, (0, img_h))
                  to_image.save(clip_img_path + '/' + str(m) + '_' + str(n) + ".jpg")
              else:  # 不填充
                  cv.imwrite(clip_img_path + '/' + str(m) + '_' + str(n) + ".jpg", cropped)
              n += 1
          n = 0
          m += 1
  
  
  if __name__ == '__main__':
      root = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
      data_path = os.path.join(root, 'data')
      img_path = os.path.join(data_path, 'bhfx1')
      cutting(img_path, data_path, "fw1_2021.tif", "clip_2021")
  
             

2.圖檔合并

• 合并的圖檔大小一緻

  import os
  import PIL.Image as Image
  
  def image_compose(IMAGE_SIZE=1024, IMAGE_ROW=24, IMAGE_COLUMN=19):
      to_image = Image.new('RGB', (IMAGE_SIZE*(IMAGE_COLUMN+1), IMAGE_SIZE*(IMAGE_ROW+1)))  # 建立新圖檔大小
      for y in range(0, IMAGE_ROW + 1):  # 循環周遊，把每張圖檔按順序粘貼到對應位置上
          for x in range(0, IMAGE_COLUMN + 1):
              file_name = str(y) + '_' + str(x) + ".jpg"
              img_name = os.path.join(clip_img_path, file_name) # 圖檔名
              from_image = Image.open(img_name) # 打開合并的圖檔
              to_image.paste(from_image, ((x) * IMAGE_SIZE, (y) * IMAGE_SIZE))  # 粘貼image到im的position(左上角)位置。w,h
      to_image.save(IMAGE_SAVE_PATH) # 儲存圖檔
      
  if __name__ == '__main__':
      root = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
      data_path = os.path.join(root, 'data')
      clip_img_path = os.path.join(data_path, 'clip', 'clip_2020')
      IMAGE_SAVE_PATH = os.path.join(data_path, 'img_merge', 'clip_2020.jpg')
      image_compose()