import random as rd
import cv2 as cv
import numpy as np


# 保存视频
class RecordMovie(object):

  def __init__(self, img_width, img_height):
    self.video_writer = None # 视频对象
    self.is_end = False # 结束保存视频
    self.img_width = img_width # 宽度
    self.img_height = img_height # 高度

  # 创建 视频写入对象
  def start(self, file_name, freq):
    # 创建视频格式
    four_cc = cv.VideoWriter_fourcc(*'mp4v')
    img_size = (self.img_width, self.img_height) # 视频尺寸

    # 创建视频写入对象
    self.video_writer = cv.VideoWriter()
    self.video_writer.open(file_name, four_cc, freq, img_size, True)

  # 写入图片帧
  def record(self, img):
    if self.is_end is False:
      self.video_writer.write(img)

  # 完成视频 释放资源
  def end(self):
    self.is_end = True
    self.video_writer.release()


def move_image(img_src):
  img_height, img_width = img_src.shape[:2]

  # 随机 xy平移方向与大小设置
  x_size = rd.randint(-3, 3)
  y_size = rd.randint(-3, 3)

  # 自定义转换矩阵
  transform_matrix = np.float32([[1, 0, x_size], [0, 1, y_size]])

  # 执行平移
  return cv.warpAffine(img_src, transform_matrix, (img_width, img_height))


def main():
  # 1.读取图片
  img_org = cv.imread("img.png", cv.IMREAD_GRAYSCALE)

  # 2.显示图片
  cv.imshow("org", img_org)
  cv.namedWindow("shift")

  # 3.视频文件生成
  height, width = img_org.shape[:2]
  print(height, width)
  rm = RecordMovie(width, height)

  # 设置视频文件名称 频率
  rm.start("test.mp4", 20)

  # 4.图片写入视频
  for i in range(300):
    # 图片微调调整
    img_move = move_image(img_org)
    img_move = cv.cvtColor(img_move, cv.COLOR_GRAY2RGB)

    rm.record(img_move)
    cv.imshow("shift", img_move)
    key = cv.waitKey(10)
    if key == 27: # esc 按键
      break

  # 5.关闭视频文件
  rm.end()


if __name__ == '__main__':
  main()