import cv2import numpy as np# 读取视频cap = cv2.VideoCapture('video.mp4')# 创建空白图像ret, frame = cap.read()height, width, _ = frame.shapeimg = np.zeros((height, width * 100, 3), dtype=np.uint8)# 逐帧读取视频并将其拼接到图像中i = 0while(cap.isOpened()): ret, frame = cap.read() if ret == False: break img[:, i*width:(i+1)*width, :] = frame i += 1# 保存图像cv2.imwrite('result.jpg', img)# 释放资源cap.release()如何解决ValueError: could not broadcast input array from shape (544,960,3) into shape (544,0,3)
时间: 2023-12-15 16:06:51 浏览: 40
这个错误是因为你创建的空白图像中,第二个维度的大小为width * 100,而在拼接图像时,你的代码没有考虑到这一点。
你需要在拼接图像之前计算好图像的总宽度,然后将空白图像的第二个维度调整为该总宽度。可以使用以下代码来实现:
```
# 读取视频
cap = cv2.VideoCapture('video.mp4')
# 创建空白图像
ret, frame = cap.read()
height, width, _ = frame.shape
total_width = width * 100 # 计算图像的总宽度
img = np.zeros((height, total_width, 3), dtype=np.uint8)
# 逐帧读取视频并将其拼接到图像中
i = 0
while(cap.isOpened()):
ret, frame = cap.read()
if ret == False:
break
img[:, i*width:(i+1)*width, :] = frame
i += 1
# 保存图像
cv2.imwrite('result.jpg', img)
# 释放资源
cap.release()
```
在这个修改后的代码中,total_width变量用于计算图像的总宽度,img数组的第二个维度被调整为total_width,以便在拼接图像时不会出现维度不匹配的错误。
相关问题
import cv2 # 初始化背景建模器 fgbg = cv2.createBackgroundSubtractorMOG2() # 读取视频文件 cap = cv2.VideoCapture('w5.mp4') while True: # 读取一帧图像 ret, frame = cap.read() if not ret: break # 对图像进行背景建模 fgmask = fgbg.apply(frame) # 缩放比例 scale_percent = 50 # 计算缩放后的新尺寸 width = int(frame.shape[1] * scale_percent / 100) height = int(frame.shape[0] * scale_percent / 100) dim = (width, height) # 缩放图像 frame = cv2.resize(frame, dim, interpolation=cv2.INTER_AREA) fgmask = cv2.resize(fgmask, dim, interpolation=cv2.INTER_AREA) # 对二值化结果进行形态学操作 kernel = cv2.getStructuringElement(cv2.MORPH_ELLIPSE, (5, 5)) fgmask = cv2.morphologyEx(fgmask, cv2.MORPH_OPEN, kernel) # 寻找轮廓并绘制矩形框 contours, hierarchy = cv2.findContours(fgmask, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE) for contour in contours: area = cv2.contourArea(contour) if area > 1500: # 去除过小的噪点 x, y, w, h = cv2.boundingRect(contour) cv2.rectangle(frame, (x, y), (x + w, y + h), (0, 0, 255), 2) # 显示结果 cv2.imshow('frame', frame) cv2.imshow('fgmask', fgmask) if cv2.waitKey(30) == ord('q'): break # 释放资源 cap.release() cv2.destroyAllWindows()用pyqt5帮这个程序做一个可视化界面
可以使用PyQt5来实现可视化界面,以下是一个简单的示例代码:
```python
import sys
from PyQt5.QtWidgets import QApplication, QWidget, QLabel, QPushButton, QVBoxLayout
import cv2
import numpy as np
class VideoPlayer(QWidget):
def __init__(self):
super().__init__()
# 初始化背景建模器
self.fgbg = cv2.createBackgroundSubtractorMOG2()
# 创建界面元素
self.label = QLabel(self)
self.button = QPushButton('开始/暂停', self)
self.button.clicked.connect(self.toggle_playback)
# 创建布局并添加元素
layout = QVBoxLayout()
layout.addWidget(self.label)
layout.addWidget(self.button)
self.setLayout(layout)
# 初始化视频播放状态
self.playing = False
# 读取视频文件
self.cap = cv2.VideoCapture('w5.mp4')
# 启动定时器
self.timer = self.startTimer(30)
def toggle_playback(self):
self.playing = not self.playing
def timerEvent(self, event):
if self.playing:
# 读取一帧图像
ret, frame = self.cap.read()
if not ret:
# 视频播放结束
self.playing = False
self.cap.release()
cv2.destroyAllWindows()
return
# 对图像进行背景建模
fgmask = self.fgbg.apply(frame)
# 缩放比例
scale_percent = 50
# 计算缩放后的新尺寸
width = int(frame.shape[1] * scale_percent / 100)
height = int(frame.shape[0] * scale_percent / 100)
dim = (width, height)
# 缩放图像
frame = cv2.resize(frame, dim, interpolation=cv2.INTER_AREA)
fgmask = cv2.resize(fgmask, dim, interpolation=cv2.INTER_AREA)
# 对二值化结果进行形态学操作
kernel = cv2.getStructuringElement(cv2.MORPH_ELLIPSE, (5, 5))
fgmask = cv2.morphologyEx(fgmask, cv2.MORPH_OPEN, kernel)
# 寻找轮廓并绘制矩形框
contours, hierarchy = cv2.findContours(fgmask, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
for contour in contours:
area = cv2.contourArea(contour)
if area > 1500: # 去除过小的噪点
x, y, w, h = cv2.boundingRect(contour)
cv2.rectangle(frame, (x, y), (x + w, y + h), (0, 0, 255), 2)
# 将图像转换为RGB格式并显示
frame = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)
image = np.rot90(frame)
height, width, channel = image.shape
bytesPerLine = 3 * width
qImg = QImage(image.data, width, height, bytesPerLine, QImage.Format_RGB888)
self.label.setPixmap(QPixmap.fromImage(qImg))
if __name__ == '__main__':
app = QApplication(sys.argv)
player = VideoPlayer()
player.show()
sys.exit(app.exec_())
```
这个程序中,我们创建了一个名为 `VideoPlayer` 的类,继承自 `QWidget`,并包含一个标签和一个按钮。在类的初始化方法中,我们创建了这些界面元素,并将它们添加到一个垂直布局中。我们还初始化了视频播放状态和定时器,并在定时器回调函数中读取视频帧、进行背景建模、绘制矩形框等处理,并将处理后的图像显示在标签中。在按钮的点击事件中,我们切换视频播放状态。最后,我们使用 `QApplication` 启动了程序,并显示了 `VideoPlayer` 窗口。
注意:在运行程序之前,需要确保已经正确安装了 PyQt5 和 OpenCV。
import time from serial import Serial import serial.tools.list_ports import cv2 import numpy as np cap1=cv2.VideoCapture("/Users/yankaipan/Desktop/stand.mp4") cap2=cv2.VideoCapture("/Users/yankaipan/Desktop/apple.mp4") cap3=cv2.VideoCapture("/Users/yankaipan/Desktop/bamboo.mp4") cap4=cv2.VideoCapture("/Users/yankaipan/Desktop/rubbish.mp4") port_list = list(serial.tools.list_ports.comports()) port_list_1 =list(port_list[2]) port_serial = port_list_1[0] arduinoData=serial.Serial(port_serial,9600) time.sleep(1) current_video=None #记录当前正在播放的视频 while True: while (arduinoData.inWaiting()==0): pass dataPacket=arduinoData.readline() dataPacket=dataPacket.decode().strip() print(dataPacket) time.sleep(3) # if dataPacket=="b": # print("1") # else: # print('2') if dataPacket=="a": if current_video!=cap1: #判断是否需要切换视频 if current_video is not None: current_video.release() current_video=cap1 while(cap1.isOpened()): ret, frame = cap1.read() if ret == True: cv2.imshow('Frame', frame) if cv2.waitKey(25) & 0xFF == ord('q'): break else: cap1.set(cv2.CAP_PROP_POS_FRAMES,0) current_video.set(cv2.CAP_PROP_FRAMES,0) elif dataPacket=="b": if current_video!=cap2: #判断是否需要切换视频 if current_video is not None: current_video.release() current_video=cap2 while(cap2.isOpened()): ret, frame = cap2.read() if ret == True: cv2.imshow('Frame', frame) if cv2.waitKey(25) & 0xFF == ord('q'): break else: #cap2.set(cv2.CAP_PROP_POS_FRAMES,0) current_video.set(cv2.CAP_PROP_FRAMES,0) elif dataPacket=="c": if current_video!=cap3: #判断是否需要切换视频 if current_video is not None: current_video.release() current_video=cap3 while(cap3.isOpened()): ret, frame = cap3.read() if ret == True: cv2.imshow('Frame', frame) if cv2.waitKey(25) & 0xFF == ord('q'): break else: #cap3.set(cv2.CAP_PROP_POS_FRAMES,0) current_video.set(cv2.CAP_PROP_FRAMES,0) elif dataPacket=="d": if current_video!=cap4: #判断是否需要切换视频 if current_video is not None: current_video.release() current_video=cap4 while(cap4.isOpened()): ret, frame = cap4.read() if ret == True: cv2.imshow('Frame', frame) if cv2.waitKey(25) & 0xFF == ord('q'): break else: #cap4.set(cv2.CAP_PROP_POS_FRAMES,0) current_video.set(cv2.CAP_PROP_FRAMES,0) cv2.destroyAllWindows()代码运行播放a视频时接收到其他b或c或d;并不能播放相应的视频,该怎样修改代码才能让代码运行时实现这一功能?
在你的代码中,当收到指令时,会先判断当前播放的视频是不是需要切换的视频,如果是则释放当前视频,播放新的视频。但是在播放新的视频时,你使用了一个 while 循环读取视频帧并显示,这个循环是不会退出的,直到视频播放完毕或者用户按下 'q' 键退出。因此,即使收到了其他指令,也无法立即停止当前的视频播放。
为了解决这个问题,你可以在收到新指令时,先将当前正在播放的视频暂停或者停止,然后释放视频资源,最后根据接收到的指令切换到相应的视频,并开始播放新的视频。下面是修改后的代码:
```
import time
from serial import Serial
import serial.tools.list_ports
import cv2
import numpy as np
cap1 = cv2.VideoCapture("/Users/yankaipan/Desktop/stand.mp4")
cap2 = cv2.VideoCapture("/Users/yankaipan/Desktop/apple.mp4")
cap3 = cv2.VideoCapture("/Users/yankaipan/Desktop/bamboo.mp4")
cap4 = cv2.VideoCapture("/Users/yankaipan/Desktop/rubbish.mp4")
port_list = list(serial.tools.list_ports.comports())
port_list_1 = list(port_list[2])
port_serial = port_list_1[0]
arduinoData = serial.Serial(port_serial, 9600)
time.sleep(1)
current_video = None # 记录当前正在播放的视频
while True:
while (arduinoData.inWaiting() == 0):
pass
dataPacket = arduinoData.readline()
dataPacket = dataPacket.decode().strip()
print(dataPacket)
time.sleep(3)
# 停止当前视频的播放
if current_video is not None:
current_video.release()
# 切换到新的视频
if dataPacket == "a":
current_video = cap1
elif dataPacket == "b":
current_video = cap2
elif dataPacket == "c":
current_video = cap3
elif dataPacket == "d":
current_video = cap4
# 开始播放新的视频
if current_video is not None:
current_video.set(cv2.CAP_PROP_POS_FRAMES, 0) # 将视频设置为第一帧
while (current_video.isOpened()):
ret, frame = current_video.read()
if ret == True:
cv2.imshow('Frame', frame)
if cv2.waitKey(25) & 0xFF == ord('q'):
break
else:
current_video.set(cv2.CAP_PROP_POS_FRAMES, 0)
cv2.destroyAllWindows()
```
在修改后的代码中,当收到新指令时,会先停止当前视频的播放,并释放资源。然后根据指令选择新的视频并开始播放。在播放新的视频时,每次读取一帧并显示,如果用户按下 'q' 键,则退出循环停止视频播放。