import cv2
import sys
faceCascade = cv2.CascadeClassifier('haarcascade_frontalface_default.xml')
video_capture = cv2.VideoCapture(0)
img_counter = 0
while True:
# Capture frame-by-frame
ret, frame = video_capture.read()
gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
k = cv2.waitKey(1)
faces = faceCascade.detectMultiScale(
gray,
scaleFactor=1.5,
minNeighbors=5,
minSize=(30, 30),
flags=cv2.CASCADE_SCALE_IMAGE
)
# Draw a rectangle around the faces
for (x, y, w, h) in faces:
cv2.rectangle(frame, (x, y), (x+w, y+h), (0, 255, 0), 2)
# Display the resulting frame
cv2.imshow('FaceDetection', frame)
if k%256 == 27: #ESC Pressed
break
elif k%256 == 32:
# SPACE pressed
img_name = "facedetect_webcam_{}.png".format(img_counter)
cv2.imwrite(img_name, frame)
print("{} written!".format(img_name))
img_counter += 1
# When everything is done, release the capture
video_capture.release()
cv2.destroyAllWindows()
after running the code in python the image of my webcam turn into this
Your code works for me without any problems.
The output image looks like there is a problem with the data type of the input image.
Something similar was discussed here:
https://answers.opencv.org/question/174027/c-ycbcr422-to-rgb-convert-from-raw-data-file/
Can you please also post your input frame grayscale image?
What camera are you using?
try add this code after video_capture.read() and post output.
print(frame.dtype)
print(frame.shape)
Mine is: dtype - uint8, shape - (480, 640, 3).
You can have a problem with the number of channels (for example RGBA) and rectangle function.
These are just my ideas of what could be wrong. But for me, your code works fine.
br Jozef
Related
I'm currently practicing opencv and tried the face recognition code and it's working fine. I'd like to get notified if I'm away from the screen for more than 2 mins. I'm trying to play an audio file when I'm away and stop it when I'm back.
import cv2 as cv
import sys
cascPath = sys.argv[1]
faceCascade = cv2.CascadeClassifier(cascPath)
video_capture = cv.VideoCapture(0)
while True:
# Capture frame-by-frame
ret, frame = video_capture.read()
gray = cv.cvtColor(frame, cv.COLOR_BGR2GRAY)
faces = faceCascade.detectMultiScale(
gray,
scaleFactor=1.1,
minNeighbors=5,
minSize=(30, 30),
flags=cv.CASCADE_SCALE_IMAGE
)
# Draw a rectangle around the faces
for (x, y, w, h) in faces:
cv.rectangle(frame, (x, y), (x+w, y+h), (0, 255, 0), 2)
# Display the resulting frame
cv.imshow('Video', frame)
# check if the tuple faces is empty
if len(faces) == 0:
start_time = time.time()
while len(faces) == 0:
print('person is away for ',time.time()-start_time)
d_time = time.time()
if d_time-start_time > 120:
pygame.mixer.init()
sound = pygame.mixer.Sound("Recording.mp3")
sound.play(5)
if cv.waitKey(1) & 0xFF == ord('q'):
break
video_capture.release()
cv.destroyAllWindows()
I'm trying to detect the bottle orientation in a packing line, for this I'm using haar cascade with python opencv but I getting false positive detections.
This is the image that the system should detect as a positive:
But the problem is that the system will detect as a positive the following image:
Do you know is there is something better than haar cascade that I could use for this or how I could solve the issue with the false positive detection?
This is the complete code:
import cv2
import sys
cascPath = "cascadeedgedbottle.xml"
bottleCascade = cv2.CascadeClassifier(cascPath)
video_capture = cv2.VideoCapture(0)
while True:
# Capture frame-by-frame
ret, frame = video_capture.read()
gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
contrast =2
brightness = 5
bottle = bottleCascade.detectMultiScale(
gray,
scaleFactor=1.05,
minNeighbors=10,
minSize=(125, 125),
flags = cv2.CASCADE_SCALE_IMAGE
#flags=cv2.cv.CV_HAAR_SCALE_IMAGE
)
print("Found {0} bottles!".format(len(faces)))
# Draw a rectangle around the bottle
for (x, y, w, h) in bottle:
cv2.rectangle(frame, (x, y), (x+w, y+h), (0, 255, 0), 2)
# Display the resulting frame
cv2.imshow('Video', frame)
if cv2.waitKey(1) & 0xFF == ord('q'):
break
video_capture.release()
cv2.destroyAllWindows()
I am working on a face detection use case and want to print a message when the face is not detected in the frame, and draw the bounding box when the face is detected. I am using open-cv for the same
Here is my code so far, please let me know what changes need to be made.
import cv2
cascPath = 'haarcascade_frontalface_dataset.xml'
faceCascade = cv2.CascadeClassifier(cascPath)
video_capture = cv2.VideoCapture(0)
while True :
_, frame = video_capture.read(0)
gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
# cv2.imshow("face detection", frame)
faces = faceCascade.detectMultiScale(
gray,
scaleFactor=1.1,
minNeighbors=5,
minSize=(30, 30),
flags=cv2.CASCADE_SCALE_IMAGE
)
# Draw a rectangle around the faces
for (x, y, w, h) in faces:
if w == 0:
cv2.putText(frame,'No face',(0,130), font, 1, (200,255,155))
else:
cv2.rectangle(frame, (x, y), (x + w, y + h), (0, 255, 0), 2)
# Display the resulting frame in browser
cv2.imshow('Video', frame)
if cv2.waitKey(1) & 0xFF == ord('q'):
break
# When everything is done, release the capture
video_capture.release()
cv2.destroyAllWindows()
I figured out the solution, go through it if you want to have a look , just add this if statement before for loop, it writes no face in the window if no face is detected
if len(faces) == 0:
cv2.putText(frame,'No face',(0,130), 4,1, (200,255,155))
This guide in geeksforgeeks can help you. Also you can follow link on tproger, so I recommend to use google transltator.
https://www.geeksforgeeks.org/python-opencv-cv2-puttext-method/
https://tproger.ru/translations/opencv-python-guide/#text
I am trying to detect objects from an mp4 video file using OpenCV in Python. I am able to detect the objects in the video.
I would like to get the timestamp of the position at which the object was detected in the video file and write it to a text file.
Here is my code so far:
import cv2
my_cascade = cv2.CascadeClassifier('toy.xml')
def detect(gray, frame):
toys= my_cascade.detectMultiScale(gray, 1.3, 5)
for (x, y, w, h) in toys:
cv2.rectangle(frame, (x, y), (x+w, y+h), (255, 0, 0), 2)
#Logic to write time stamp to file goes here
return frame
video_capture = cv2.VideoCapture('home.mp4')
cv2.startWindowThread()
while True:
_, frame = video_capture.read()
gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
canvas = detect(gray, frame)
cv2.imshow('Video', canvas)
if cv2.waitKey(1) & 0xFF == ord('q'):
break
video_capture.release()
cv2.destroyAllWindows()
I tried to use VideoCapture's method get() using property identifier like this:
video_capture.get(CV_CAP_PROP_POS_MSEC)
but get an error name 'CV_CAP_PROP_POS_MSEC' is not defined
Seems like cv2 does not have this method or property identifier implemented.
Is there any other way in cv2 to implement what I want?
Please help.
SOLVED
This will print timestamp of the position of object everytime it is detected in the video.
Here is the working code:
import cv2
my_cascade = cv2.CascadeClassifier('toy.xml')
def detect(gray, frame):
toys= my_cascade.detectMultiScale(gray, 1.3, 5)
for (x, y, w, h) in toys:
cv2.rectangle(frame, (x, y), (x+w, y+h), (255, 0, 0), 2)
print("Toy Detected at: "+str(video_capture.get(cv2.CAP_PROP_POS_MSEC)))
return frame
video_capture = cv2.VideoCapture('home.mp4')
cv2.startWindowThread()
while True:
_, frame = video_capture.read()
gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
canvas = detect(gray, frame)
cv2.imshow('Video', canvas)
if cv2.waitKey(1) & 0xFF == ord('q'):
break
video_capture.release()
cv2.destroyAllWindows()
cv2 does have the property implemented, but the full name needs to be used.
This should work
import cv2
my_cascade = cv2.CascadeClassifier('toy.xml')
def detect(gray, frame):
toys= my_cascade.detectMultiScale(gray, 1.3, 5)
for (x, y, w, h) in toys:
cv2.rectangle(frame, (x, y), (x+w, y+h), (255, 0, 0), 2)
#Logic to write time stamp to file goes here
return frame
video_capture = cv2.VideoCapture('home.mp4')
cv2.startWindowThread()
while True:
_, frame = video_capture.read()
gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
canvas = detect(gray, frame)
print (video_capture.get(cv2.CAP_PROP_POS_MSEC))
cv2.imshow('Video', canvas)
if cv2.waitKey(1) & 0xFF == ord('q'):
break
video_capture.release()
cv2.destroyAllWindows()
i.e. you want the property of the instance video_capture not the generic class VideoCapture and the property name is prefixed by the class cv2.. The property name is either CAP_PROP_POS_MSECor CV_CAP_PROP_MSEC - depending on the OpenCV version (see Can't get VideoCapture property as the property identifier are not defined ).
I has raspberry pi 3 with raspbian jessie installed. Open CV3 and python 3.0 also installed. I get a python sample code which detect the face. I need write some text on the screen but it's not write on it. I need write text once instead of repeated on top of each faces. Below is the code
import cv2
import sys
from tkinter import *
from tkinter import messagebox
faceCascade = cv2.CascadeClassifier('haarcascade_frontalface_default.xml')
video_capture = cv2.VideoCapture(0)
video_capture.set(3,500)
video_capture.set(4,300)
video_capture.set(12, 0.1)
frameWidth = int(video_capture.get(cv2.CAP_PROP_FRAME_WIDTH))
frameHeight = int(video_capture.get(cv2.CAP_PROP_FRAME_HEIGHT))
while True:
# Capture frame-by-frame
ret, frame = video_capture.read()
gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
faces = faceCascade.detectMultiScale(
gray,
scaleFactor=1.1,
minNeighbors=5,
minSize=(30, 30),
flags=cv2.CASCADE_SCALE_IMAGE
)
# Draw a rectangle around the faces
for (x, y, w, h) in faces:
cv2.rectangle(frame, (x, y), (x+w, y+h), (0, 255, 0), 2)
#cv2.putText(frame, 'How are you', (x - 1, y - 1), cv2.FONT_HERSHEY_PLAIN,2,(0, 255, 0))
#if the puttext at here, it will write the text on top of each face detected. But I just need the text appear once.
# Display the resulting frame
cv2.imshow('Video', frame)
if len(faces) > 0:
cv2.putText(img = frame, text = 'How are you', org = (int(frameWidth/2 - 20),int(frameHeight/2)), fontFace = cv2.FONT_HERSHEY_DUPLEX, fontScale = 3,
color = (0, 255, 0))
#print(int(frameWidth/2 - 20),int(frameHeight/2))
#print('Found ' + str(len(faces)) + ' face(s)')
if cv2.waitKey(1) & 0xFF == ord('q'):
break
# When everything is done, release the capture
video_capture.release()
cv2.destroyAllWindows()
You are calling imshow before putText so you'll never see the results of putText. Move the imshow statement to the line before waitKey.