Questions tagged [opencv]
OpenCV (Open Source Computer Vision) is a library for real time computer vision. When using this tag, please add a language specific tag (python, c++, ...), if relevant.
opencv
73,556
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Low-latency RTSP stream using OpenCV and ffmpeg seems to ignore flags
I'm writing a Qt6 application in C++ which should display and optionally store mutltiple RTSP streams. Currently, I'm using OpenCV to capture the stream:
m_capture = new cv::VideoCapture("rtsp://...
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1
answer
45
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How to resize an image and keep backround empty using OpenCV
I have the following 256x256 image:
I want to resize it to 100x100 pixels using OpenCV:
img = cv2.imread('image.png')
p = 100/256
new_width = int( img.shape[1] * p )
new_height = int( img.shape[0] *...
- 157
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33
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Sobel filter angle value overlaps
I am trying to get the orientation of the edges detected using the Sobel filter. However, the angle of the pixels kept overlapping. For example, in this image: , the descending slopes have 2 colors, ...
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Unable to open video with OpenCV python [closed]
I am unable to open a .avi video file with OpenCV python. In my head it is a very simple task, but for some reason, I am unable to open the file.
When I run os.path.exists(<video_file_path>), it ...
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60
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why cv::waitKey(x) is not closing frame after x seconds? [closed]
#include <opencv2/imgcodecs.hpp>
#include <opencv2/highgui.hpp>
#include <string>
int main()
{
std::string path = "wallpaperflare.jpg";
cv::Mat img = cv::imread(...
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43
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How do you compile OpenCV with Python with CUDA Support on Rocky Linux 9?
I am trying to build opencv-python per the official instructions with support for CUDA so I can run SIFT. When I try to build with pip wheel . --verbose I get:
-- Configuring incomplete, errors ...
- 1,661
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45
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Receiving an RTSP stream with a custom codec in Python (on Windows)
I am building a pyside application on windows and I am trying to receive an rtsp stream carrying data encoded in a custom codec. I've tried a few things that didn't work, so I need some help.
I first ...
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Title: Extracting Tabular Data from Images Using Python and Tesseract OCR
I'm currently working on a project where I need to extract data in tabular format from images. The images contain data in a tabular format, and I need to save this data in a structured way for further ...
- 153
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1
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46
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To select the first closed round of an image while reading it from left to right
Here, I used the character image like this. When I tried to select only the first closed round portion of the input image, while scanning it from left to right using open_cv -, I got the whole outer ...
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34
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Processing frames from a video using OpenCvSharp make the cpu usage reaching 100%. is there a way to avoid the cpu from reaching that high usage? [closed]
this is the class code:
i used the profiler to see where and when the cpu usage reach 100%.
it happens on this lines:
when reading:
if (_videoCapture.Read(frame))
and when converting:
return ...
- 11.2k
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28
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Ceres-Solver-does the initial reference 3D point matter? Experiencing significantly high reprojection error
So I have a set of 2d-3d correspondence points where the 2d coordinate points are detected by a corner detection algorithm (not written by me, and verified to be correct) and 3d coordinate points ...
- 73
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26
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inverted rows,cols in cv.resize
I don't understand why the np.shape passed to cv.resize needs me to swap the tuple elements:
# Our operations on the frame come here
gray = cv.cvtColor(frame, cv.COLOR_BGR2GRAY)
# Display the ...
- 59.9k
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can opencv.js really find page corners
Has anyone had any success with opencv.js in finding page corners? There is a lot of noise on various discussion sites about it's ability - but I cannot find it to work when looking for a document ...
- 1,171
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cv2 not acting as in all docs i can find [closed]
Here the code:
import cv2
import numpy
img = cv2.VideoCapture(0)
run = True
while run:
frame = img.read()
cv2.imshow("baka", "hi")
This the error it gave me. I can’t ...
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0
answers
17
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JavaCV frame reading not working on Raspberry Pi
i am currently developing an application to scan QR codes with Java and JavaCV.
On my mac, it works just fine. Opens the camera, reads the frames and detects + decodes the QR code.
When i run the code ...
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