python 用OpenCV 将图片转视频_cv2.videowriter

import os
import cv2
import numpy as np
 
cv2.VideoWriter（）参数  cv2.VideoWriter() 是 OpenCV 中用于创建视频文件的类。它的参数如下：
filename：保存视频的文件名。
fourcc：指定视频编解码器的 FourCC 代码，用于将视频压缩成指定格式，例如：“XVID”、“MJPG”, "mp4v"等。可以使用 cv2.VideoWriter_fourcc() 函数来获取 FourCC 代码。
fps：指定视频帧率，即每秒显示的帧数。
frameSize：指定视频帧的大小，即视频的分辨率，可以使用 (width, height) 形式的元组来指定。
isColor：指定是否为彩色视频。如果为 True，则为彩色视频；如果为 False，则为灰度视频。
其中，前三个参数是必需的，后两个参数是可选的。例如：
fps = 25
# cv2.VideoWriter('output.avi', cv2.VideoWriter_fourcc(*'XVID'), fps, (640, 480))
 
def resize_img(target_size, image_paths):
    #target_size = (1000, 1000)  # 所有图片缩放设置一致尺寸，目标尺寸
    #image_paths= './images'
    path_new = './images_new'
    if not os.path.exists(path_new):
        os.makedirs(path_new)
    filelists = []
    imglist = []
    for i in os.listdir(image_paths):
        file_path = os.path.join(image_paths, i)
        print(file_path)
        img = cv2.imdecode(np.fromfile(file_path, dtype=np.uint8), cv2.IMREAD_COLOR)
        size = img.shape
        h, w = size[0], size[1]
        target_h, target_w = target_size[1], target_size[0]
        # 确定缩放的尺寸
        scale_h, scale_w = float(h / target_h), float(w / target_w)
        print(f'scale_h:{scale_h}, scale_w:{scale_w}')
        scale = max(scale_h, scale_w) # 选择最大的缩放比率
        new_w, new_h = int(w / scale), int(h / scale)
        # 缩放后其中一条边和目标尺寸一致
        resize_img = cv2.resize(img, (new_w, new_h))
        # 图像上、下、左、右边界分别需要扩充的像素数目
        top = int((target_h - new_h) / 2)
        bottom = target_h - new_h - top
        left = int((target_w - new_w) / 2)
        right = target_w - new_w - left
        print(f'top:{top} bottom:{bottom} left:{left} right:{right}') 
        cv2.imwrite(os.path.join(path_new, f'new_{i}'), resize_img) # 写入本地文件
        # 填充至 target_w * target_h
        pad_img = cv2.copyMakeBorder(resize_img, top, bottom, left, right, cv2.BORDER_CONSTANT, value=[0, 0, 0])
        # cv2.imshow('img', pad_img)
        # cv2.waitKey(1000)
        filelists.append(os.path.join(path_new, f'new_{i}'))
        imglist.append(pad_img)
    return filelists, imglist
 
 
def cut_img(scale):
    # 读取本地图片文件夹
    path = './images'
    path_new = './images_new'
    if not os.path.exists(path_new):
        os.makedirs(path_new)
    filelists = []
    imglist = []
    for i in os.listdir(path):
        file_path = os.path.join(path, i)
        print(file_path)
        img = cv2.imdecode(np.fromfile(file_path, dtype=np.uint8), cv2.IMREAD_COLOR)
        size = img.shape
        h, w = size[0], size[1]
        rate1 = scale.split(':')
        w1 = int((w - w * int(rate1[0]) / int(rate1[1])) / 2)
        w2 = int(w - (w - w * int(rate1[0]) / int(rate1[1])) / 2)
        resize_img = img[0:h, w1:w2]
        cv2.imwrite(os.path.join(path_new, f'new_{i}'), resize_img) # 写入本地文件
        filelists.append(os.path.join(path_new, f'new_{i}'))
        imglist.append(resize_img)
    return filelists, imglist
 
 
def cut_img1(images, scale):
    # 接收图片链接
    imglist = []
    filelists = []
    for i in images:
        img_url = i
        file_name = img_url.split('/')[-1]
        path_new = f'./images_new/{file_name}'
        try:
            res = requests.get(img_url)
        except:
            continue
        if 'RIFF' in str(res.content)[:500] or 'GIF' in str(res.content)[:500]:
            file_name = file_name.split('.')[0] + '.jpg'
            path_new1 = f'./images_new/{file_name}'
            img = Image.open(BytesIO(res.content)).convert('RGB')
            img.save(path_new1)
            img = cv2.imdecode(np.fromfile(path_new1, dtype=np.uint8), cv2.IMREAD_COLOR)
        else:
            image = np.asarray(bytearray(res.content), dtype="uint8")
            img = cv2.imdecode(image, cv2.IMREAD_COLOR)
        size = img.shape
        h, w = size[0], size[1]
        rate1 = scale.split(':')
        w1 = int((w - w * int(rate1[0]) / int(rate1[1])) / 2)
        w2 = int(w - (w - w * int(rate1[0]) / int(rate1[1])) / 2)
        resize_img = img[0:h, w1:w2]
        imglist.append(resize_img)
        filelists.append(resize_img.shape)
    return filelists, imglist
 
def image_to_video():
    scale = '1:1'  # 裁剪比例,并保持高度不变
    # scale = '3:4'
    # scale = '9:16'
    # 前提是所有图片尺寸一致，将图片按比例裁剪
    filelists, imglist = cut_img(scale) 
    # target_size = (1000, 1000) # 指定尺寸
    # image_paths = './images'   # 本地图片文件夹路径
    # 缩放, 将所有图片尺寸缩放或者扩大到指定尺寸
    # filelists, imglist = resize_img(target_size, image_paths)
    fourcc = cv2.VideoWriter.fourcc(*'avc1') #avc1模式下生成的视频上传到oss后链接可以在浏览器访问 mp4v模式下生成的视频需要用ffmpeg将视频格式转成H264
    im = cv2.imread(filelists[0])
    print(im.shape)
    shape1 = (im.shape[1], im.shape[0])    #需要转为视频的图片的尺寸, 视频的分辨率
    print('shape1:', shape1)
    fps = 1
    writer = cv2.VideoWriter('./output.mp4', fourcc, fps , shape1)
    # for file_path in filelists:
    #     img = cv2.imread(file_path)
    #     writer.write(img)
 
    for i in imglist:
        writer.write(i)
    writer.release()
 
 
image_to_video()
 
 

 我们无法打开output3.mp4。这可能是因为文件类型不受支
持、文件扩展名不正确或文件已损坏，0xC00D36C4

如果生成的视频报这个错，一般是视频的分辨率 设置的不匹配