Python3视频转字符动画的实例代码

# -*- coding:utf-8 -*-
import json
import os
import subprocess
from pathlib import Path
from cv2 import cv2
import numpy as np
from time import time
import webbrowser
play_chars_js = '''
let i = 0;
window.setInterval(function(){
  let img = frames[i++];
  let html = ""
  for(let line of img){
    for(let char of line){
      let [[r,g,b], ch] = char;
      html += '<span style="color:rgb(' + r + ', ' + g + ', '+ b + ');">'+ ch + '</span>'
      // html += '<span style="background-color:rgb(' + r + ', ' + g + ', '+ b + ');">'+ ch + '</span>'
    }
    html += "<br>"
  }
  document.getElementsByClassName("video-panel")[0].innerHTML = html
}, 1000/fps);
document.getElementsByTagName("audio")[0].play();
'''
class VideoToHtml:
  # 像素形状，因为颜色已经用rgb控制了，这里的pixels其实可以随意排
  pixels = "$#@&%ZYXWVUTSRQPONMLKJIHGFEDCBA098765432?][}{/)(><zyxwvutsrqponmlkjihgfedcba*+1-."
  def __init__(self, video_path, fps_for_html=8, time_interval=None):
    """
    :param video_path: 字符串, 视频文件的路径
    :param fps_for_html: 生成的html的帧率
    :param time_interval: 用于截取视频（开始时间，结束时间）单位秒
    """
    self.video_path = Path(video_path)
    # 从指定文件创建一个VideoCapture对象
    self.cap = cv2.VideoCapture(video_path)
    self.width = self.cap.get(cv2.CAP_PROP_FRAME_WIDTH)
    self.height = self.cap.get(cv2.CAP_PROP_FRAME_HEIGHT)
    self.frames_count_all = self.cap.get(cv2.CAP_PROP_FRAME_COUNT)
    self.fps = self.cap.get(cv2.CAP_PROP_FPS)
    self.resize_width = None
    self.resize_height = None
    self.frames_count = 0
    self.fps_for_html = fps_for_html
    self.time_interval = time_interval
  def video2mp3(self):
    """#调用ffmpeg获取mp3音频文件"""
    mp3_path = self.video_path.with_suffix('.mp3')
    subprocess.call('ffmpeg -i ' + str(self.video_path) + ' -f mp3 ' + str(mp3_path), shell=True)
    return mp3_path
  def set_width(self, width):
    """只能缩小，而且始终保持长宽比"""
    if width >= self.width:
      return False
    else:
      self.resize_width = width
      self.resize_height = int(self.height * (width / self.width))
      return True
  def set_height(self, height):
    """只能缩小，而且始终保持长宽比"""
    if height >= self.height:
      return False
    else:
      self.resize_height = height
      self.resize_width = int(self.width * (height / self.height))
      return True
  def resize(self, img):
    """
    将img转换成需要的大小
    原则：只缩小，不放大。
    """
    # 没指定就不需resize了
    if not self.resize_width or not self.resize_height:
      return img
    else:
      size = (self.resize_width, self.resize_height)
      return cv2.resize(img, size, interpolation=cv2.INTER_CUBIC)
  def get_img_by_pos(self, pos):
    """获取到指定位置的帧"""
    # 把指针移动到指定帧的位置
    self.cap.set(cv2.CAP_PROP_POS_FRAMES, pos)
    # cap.read() 返回值介绍：
    #  ret 布尔值，表示是否读取到图像
    #  frame 为图像矩阵，类型为 numpy.ndarray.
    ret, frame = self.cap.read()
    return ret, frame
  def get_frame_pos(self):
    """生成需要获取的帧的位置，使用了惰性求值"""
    step = self.fps / self.fps_for_html
    # 如果未指定
    if not self.time_interval:
      self.frames_count = int(self.frames_count_all / step) # 更新count
      return (int(step * i) for i in range(self.frames_count))
    # 如果指定了
    start, end = self.time_interval
    pos_start = int(self.fps * start)
    pos_end = int(self.fps * end)
    self.frames_count = int((pos_end - pos_start) / step) # 更新count
    return (pos_start + int(step * i) for i in range(self.frames_count))
  def get_imgs(self):
    assert self.cap.isOpened()
    for i in self.get_frame_pos():
      ret, frame = self.get_img_by_pos(i)
      if not ret:
        print("读取失败，跳出循环")
        break
      yield self.resize(frame) # 惰性求值
    # 结束时要释放空间
    self.cap.release()
  def get_char(self, gray):
    percent = gray / 255 # 转换到 0-1 之间
    index = int(percent * (len(self.pixels) - 1)) # 拿到index
    return self.pixels[index]
  def get_json_pic(self, img):
    """测试阶段，不实用"""
    json_pic = []
    # 宽高刚好和size相反，要注意。（这是numpy的特性。。）
    height, width, channel = img.shape
    # 转换成灰度图，用来选择合适的字符
    img_gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
    for y in range(height):
      line = []
      for x in range(width):
        r, g, b = img[y][x]
        gray = img_gray[y][x]
        char = self.get_char(gray)
        line.append([[int(r), int(g), int(b)], char])
      json_pic.append(line)
    return json.dumps(json_pic)
  def write_html_with_json(self, file_name):
    """测试阶段，不实用"""
    mp3_path = self.video2mp3()
    time_start = time()
    with open(file_name, 'w') as html:
      # 要记得设置monospace等宽字体，不然没法玩
      html.write('<!DOCTYPE html>'
            '<html>'
            '<body style="font-family: monospace; font-size: small; font-weight: bold; text-align: center; line-height: 0.8;">'
            '<div class="video-panel"></div>'
            f'<audio src="{mp3_path.name}" autoplay controls></audio>'
            '</body>'
            '<script>'
            'var frames=[\n')
      try:
        i = 0
        for img in self.get_imgs():
          json_pic = self.get_json_pic(img)
          html.write(f"{json_pic},")
          if i % 20:
            print(f"进度：{i/self.frames_count * 100:.2f}%, 已用时：{time() - time_start:.2f}")
          i += 1
      finally:
        html.write('\n];\n'
              f'let fps={self.fps_for_html};\n'
              f'{play_chars_js}'
              '</script>\n'
              '</html>')
def main():
  # 视频路径，换成你自己的
  video_path = "ceshi.mp4"
  video2html = VideoToHtml(video_path, fps_for_html=8)
  video2html.set_width(120)
  html_name = Path(video_path).with_suffix(".html").name
  video2html.write_html_with_json(html_name)
if __name__ == "__main__":
  main()