| show | version | enable_checker |
|---|---|---|
step |
1.0 |
true |
- 上次研究了 动画过程的细节
- 缓动 ease
- 可以有 缓入和缓出
- 可有二次、余弦等缓入公式
- 可以把动画效果保存成视频文件吗？
- 链接: https://pan.baidu.com/s/1D7BYcSm201unU8wXhs4ung?pwd=1234
- 下载b2.mp4后
- 上传到Code文件夹
- 需要播放器播放
sudo apt install vlc
vlc Code/b2.mp4
import cv2
video = cv2.VideoCapture("/home/shiyanlou/Code/b2.mp4")
while (video.isOpened()):
retval, image = video.read()
cv2.namedWindow("Video",0)
cv2.resizeWindow("Video",400,300)
if retval == True:
cv2.imshow("Video",image)
else:
break
key = cv2.waitKey(1)
if key == 27:
break
video.release()
cv2.destroyAllWindows()
- 运行效果
import cv2
def decode_fourcc(cc):
return "".join([chr((int(cc) >> 8 * i) & 0xFF) for i in range(4)])
video = cv2.VideoCapture("/home/shiyanlou/Code/b2.mp4")
fps = video.get(cv2.CAP_PROP_FPS)
frame_count = video.get(cv2.CAP_PROP_FRAME_COUNT)
frame_width = video.get(cv2.CAP_PROP_FRAME_WIDTH)
frame_height = video.get(cv2.CAP_PROP_FRAME_HEIGHT)
decodes = video.get(cv2.CAP_PROP_FOURCC)
print("fps=====",fps)
print("frame_count=====",frame_count)
print("frame_width=====",frame_width)
print("frame_height=====",frame_height)
print("decodes=====",decodes)
print(f"fourcc is: {decodes, decode_fourcc(decodes)}")
- 运行结果
import cv2
video = cv2.VideoCapture("/home/shiyanlou/Code/b2.mp4")
frame_num = 0
while (video.isOpened()):
retval, frame = video.read()
cv2.namedWindow("Video",0)
cv2.resizeWindow("Video",400,300)
if retval == True:
cv2.putText(frame,"frame:"+str(frame_num),(30,80),cv2.FONT_HERSHEY_DUPLEX,2,(0,0,255),5)
cv2.imshow("Video",frame)
else:
break
key = cv2.waitKey(1)
if key == 27:
break
frame_num += 1
video.release()
cv2.destroyAllWindows()
- 效果
import cv2
video = cv2.VideoCapture("/home/shiyanlou/Code/b2.mp4")
fourcc = cv2.VideoWriter_fourcc('m', 'p', '4', 'v')
fps = cap.get(cv2.CAP_PROP_FPS)
width = int(cap.get(cv2.CAP_PROP_FRAME_WIDTH))
height = int(cap.get(cv2.CAP_PROP_FRAME_HEIGHT))
size = (width, height)
out = cv2.VideoWriter('./output.mp4',fourcc ,fps, size)
while(cap.isOpened()):
ret, frame = cap.read()
if ret == True:
out.write(frame)
cv2.imshow('frame',frame)
if cv2.waitKey(1) & 0xFF == ord('q'):
break
else:
break
cap.release()
out.release()
cv2.destroyAllWindows()
- output.mp4是随着播放而不断增长的
ffplay -autoexit filename.mp4 #-autoexit是播放完自动关闭
import cv2
videoCapture = cv2.VideoCapture("/home/shiyanlou/Code/b2.mp4")
fps = 25
size = (400, 300)
fourcc = cv2.VideoWriter_fourcc("m","p","4","v")
videoWriter = cv2.VideoWriter('resizex1.mp4', fourcc, fps, size)
while True:
success, frame = videoCapture.read()
if success:
frame = cv2.resize(frame, (400, 300))
videoWriter.write(frame)
else:
print('end')
break
videoWriter.release()
cv2.destroyAllWindows()
- 另存视频
import cv2
import random
import numpy as np
cap = cv2.VideoCapture("/home/shiyanlou/Code/b2.mp4")
# 判断视频是否读取成功
if (cap.isOpened() == False):
print("Error opening video stream or file")
# 获取帧
while (cap.isOpened()):
# Capture frame-by-frame
ret, frame = cap.read()
#设置颜色
i = random.randint(0, 255)
j = random.randint(0, 255)
k = random.randint(0, 255)
#设置线条宽度
width = random.randint(4, 10)
flag = random.randint(0, 1)
if ret == True:
# 在每一帧上画矩形和五角星，frame帧,(四个坐标参数),（颜色）,宽度
if flag == 0:
cv2.rectangle(frame, (int(200), int(300)), (int(400), int(500)), (i, j, k), width)
else:
pts = np.array([[70, 190], [222, 190], [280, 61], [330, 190], [467, 190],
[358, 260], [392, 380], [280, 308], [138, 380], [195, 260]])
pts = pts.reshape((-1, 1, 2)) # reshape为10x1x2的numpy
print(pts.shape) # (10, 1, 2)
cv2.polylines(frame, [pts], True, (i, j, k), width)
# 显示视频
cv2.imshow('Frame', frame)
# 刷新视频
cv2.waitKey(10)
# 按q退出
if cv2.waitKey(25) & 0xFF == ord('q'):
break
# 退出循环
else:
break
- 直接绘制
- 可以在时间上截取片段吗？
import cv2
import imageio
import time
frame_num = 0
video = cv2.VideoCapture("/home/shiyanlou/Code/b2.mp4")
image_list = []
while (video.isOpened()):
frame_num += 1
retval, image = video.read()
if frame_num <= 200:
continue
print(frame_num)
cv2.namedWindow("Video",0)
cv2.resizeWindow("Video",400,300)
if retval == True:
cv2.putText(image,"frame:"+str(frame_num),(30,80),cv2.FONT_HERSHEY_DUPLEX,2,(0,0,255),5)
cv2.imshow("Video",image)
image2 = cv2.cvtColor(image,cv2.COLOR_BGR2RGB)
image_list.append(image2)
else:
break
key = cv2.waitKey(1)
if key == 27 or frame_num>=300:
break
time.sleep(1/24)
video.release()
cv2.destroyAllWindows()
imageio.mimsave("./kunkun.gif",image_list,fps=24)
- 从200帧到300帧
- 帧号 写在画面上
- 输出到gif中
- 可以从空间上截取gif吗？
import cv2
import imageio
import time
frame_num = 0
video = cv2.VideoCapture("/home/shiyanlou/Code/b2.mp4")
image_list = []
while (video.isOpened()):
frame_num += 1
retval, image = video.read()
if frame_num <= 200:
continue
print(frame_num)
cv2.namedWindow("Video",0)
cv2.resizeWindow("Video",400,300)
if retval == True:
cv2.putText(image,"frame:"+str(frame_num),(30,80),cv2.FONT_HERSHEY_DUPLEX,2,(0,0,255),5)
image2 = cv2.cvtColor(image,cv2.COLOR_BGR2RGB)
image3 = image2[100:270,300:800]
cv2.imshow("Video",image3)
image_list.append(image3)
else:
break
key = cv2.waitKey(1)
if key == 27 or frame_num>=300:
break
time.sleep(1/24)
video.release()
cv2.destroyAllWindows()
imageio.mimsave("./kunkun.gif",image_list,fps=24)
- 结果
import cv2
import imageio
import time
from random import randint
frame_num = 0
video = cv2.VideoCapture("/home/shiyanlou/Code/b2.mp4")
image_list = []
while (video.isOpened()):
frame_num += 1
retval, image = video.read()
if frame_num <= 200:
continue
print(frame_num)
cv2.namedWindow("Video",0)
cv2.resizeWindow("Video",400,300)
if retval == True:
cv2.putText(image,"frame:"+str(frame_num),(30,80),cv2.FONT_HERSHEY_DUPLEX,2,(0,0,255),5)
image2 = cv2.cvtColor(image,cv2.COLOR_BGR2RGB)
image3 = image2[100:270,300:800]
r = randint(35,70)
cv2.circle(image3,(85,85),r,(255,255,0),-1)
cv2.imshow("Video",image3)
image_list.append(image3)
else:
break
key = cv2.waitKey(1)
if key == 27 or frame_num>=300:
break
time.sleep(1/24)
video.release()
cv2.destroyAllWindows()
imageio.mimsave("./kunkun.gif",image_list,fps=24)
- 最终效果
import cv2
import imageio
import time
import numpy as np
import random
import math
frame_num = 0
video = cv2.VideoCapture("/home/shiyanlou/Code/b2.mp4")
image_list = []
while (video.isOpened()):
frame_num += 1
retval, image = video.read()
if frame_num <= 20:
continue
print(frame_num)
cv2.namedWindow("Video",0)
cv2.resizeWindow("Video",400,300)
if retval == True:
cv2.putText(image,"frame:"+str(frame_num),(30,80),cv2.FONT_HERSHEY_DUPLEX,1,(0,255,255),1)
image2 = cv2.cvtColor(image,cv2.COLOR_BGR2RGB)
image3 = image2[0:500,500:900]
for num in range(0,360,15):
radius = math.radians(num)
x = int(150 + math.cos(radius) * 100)
y = int(150 + math.sin(radius) * 100)
r = random.randint(20,100)
color = np.random.randint(0,256,size=(3,)).tolist()
print("num:",num,"~color",color,"~(x,y)",(x,y),"~r",r)
image3 = cv2.circle(image3,(x, y),r,color,1)
image4 = cv2.cvtColor(image3,cv2.COLOR_RGB2BGR)
cv2.imshow("Video",image4)
image_list.append(image3)
else:
break
key = cv2.waitKey(1)
if key == 27 or frame_num>=150:
break
time.sleep(1/24)
video.release()
cv2.destroyAllWindows()
imageio.mimsave("./kun.gif",image_list,fps=24)
- 最终效果
9.为视频添加字幕效果
import cv2
from random import randint
import numpy as np
import time
#把时间转化成毫秒计时
def timestamp(txt):
s_t=list(map(int, txt.split(':')))
return s_t[0]*60000+s_t[1]*1000+s_t[2]
#打开源文件，并读取一些视频信息
cap = cv2.VideoCapture("/home/shiyanlou/Code/b2.mp4")
fourcc = cv2.VideoWriter_fourcc('m', 'p', '4', 'v')
fps = cap.get(cv2.CAP_PROP_FPS)
#print(fps)
width = int(cap.get(cv2.CAP_PROP_FRAME_WIDTH))
height = int(cap.get(cv2.CAP_PROP_FRAME_HEIGHT))
size = (width, height)
#设置导出视频的内容
out = cv2.VideoWriter('./output.mp4',fourcc ,fps, size)
#对字幕的文件进行解析
captions =[]
with open('cap.txt', 'r',encoding='UTF-8') as f:
for line in f:
l = line.strip().split(' ')
t = list(map(timestamp, l[0].split('-')))
txt = l[1]
for word in l[2:]:
txt = txt + ' '+ word
print(t,txt)
captions.append([t,txt])
#对每一帧进行加工
now = 0
cap_now = 0
while(cap.isOpened()):
ret, frame = cap.read()
if ret == True:
#输出随机乱码
for x in range(int(width/8)):
for y in range(int(height/20)):
if randint(0, 127) < 36:
r = randint(20,127)
color = np.random.randint(256,size=(3),dtype=np.uint8).tolist()
#print(color)
cv2.putText(frame,chr(r),(x*8,y*20-1),cv2.FONT_HERSHEY_DUPLEX,0.4,color,1)
#输出字幕
if cap_now < len(captions) and now >= captions[cap_now][0][1]:
cap_now = cap_now + 1
if cap_now < len(captions) and now >= captions[cap_now][0][0] and now <= captions[cap_now][0][1]:
#print(captions[cap_now][1])
cv2.putText(frame,captions[cap_now][1],(0,int(height*0.75)),cv2.FONT_HERSHEY_DUPLEX,1,(256,256,256),1,cv2.LINE_AA, True)
#显示画面
cv2.imshow('frame',frame)
out.write(frame)
if cv2.waitKey(1) & 0xFF == ord('q'):
break
else:
break
now = now + fps
cap.release()
out.release()
cv2.destroyAllWindows()
- 下面为cap.txt
00:00:00-00:00:03 Hello, I'm SDDL
00:00:03-00:00:06 Today show something you like
00:00:06-1000:59:59 Tap to text
- 运行结果
- 可以把字幕放上去
- 这次研究了视频的修改
- 视频另存
- 视频大小调整
- 视频空间裁剪
- 视频时间截取
- 在原视频上画别的
- 在原视频上添加字幕
- opencv 确实很强大
- 还能做点什么？🤔
- 下次再说👋