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Questions tagged [opencv]

Open Source Computer Vision Library, real time computer vision

3
votes
0answers
244 views

Latency on a Raspberry Pi camera

I'm making a flight controller and want to stabilize the x-y plane using optical flow, which requires almost instantaneous processing thus requires almost no latency. How much latency does the Pi ...
3
votes
0answers
811 views

Raspicam has low fps for OpenCV

So far, I've tried these tutorials: 1 & 2. I have also attempted to use this code to test it out, and the fps rate is quite low. It's just 2 -3 fps, which is not as high as when I stream via vlc ...
2
votes
0answers
1k views

RPi camera stream to OpenCV in Python

I have been searching everywhere and tested what seems to be everything in order to get OpenCV in python to accept a video stream through gst-launch-1.0 from a RPi camera connected to a RPi. So far, I ...
2
votes
0answers
227 views

How to Stream MJPEG from Pi camera?

I want to make something like Surveillance system from pi camera. How can I do that with Opencv and pi camera ? Can anyone please help me to understand How can I do like this example. I am not a pi ...
2
votes
0answers
569 views

Increase FPS PiCam in Multiprocessing

Currently, my system is only producing 10 FPS out of 20, which is my target. I'm barely hit 15 FPS in single grab-and-show simple code like this: from picamera.array import PiRGBArray from picamera ...
2
votes
0answers
2k views

Simplest way to grab camera images from Java

I want to write a software that runs on the JVM (in Scala but you can think Java). I am looking for the simplest way to capture images from the standard camera module (v2). I find the raspstill quite ...
2
votes
0answers
1k views

Corrupt JPEG data: extraneous bytes before marker, OpenCV C++, Raspberry Pi

I am trying to run OpenCV application on Raspberry PI. When video capture from an external camera starts (Logitech C270), the messages below are printed out: Corrupt JPEG data: 1 extemporaneous bytes ...
2
votes
0answers
1k views

Problems in getting two camera feeds via an OpenCV python program

I'm running a Ubuntu 14.04 LTS on my RPi 2. I've OpenCV 2.4.9 installed on it. While running a simple camera capture program works fine. Here is a code for it. import numpy as np import cv2 from ...
2
votes
0answers
703 views

Importing Lepton Thermal Module video feed into OpenCV on Raspberry pi

I'd like to import the video feed that I can capture from a thermal imagery camera I got off sparkfun for a college project of mine. But, I can't seem to get the ./raspberrypi_video into the Video ...
2
votes
0answers
917 views

OpenCV. Can't open video from usb camera on the screen

When I'm trying to start simple code, the frame opens and don't respond. import numpy as np import cv2 cap = cv2.VideoCapture(0) while(True): ret, frame = cap.read() cv2.imshow('AIR',frame) ...
2
votes
0answers
835 views

Is RaspberryPi OpenCV fast enough to run eye blink recognition?

I would like to create application that can recognise eye blink recognition on RaspberryPi with Raspberry Pi Noir camera. Eye blinks are fast, so I will have to process many frames per second. Is ...
1
vote
0answers
54 views

Error unknown machine command despite compiling without errors

I recently made a project using opencv 4 on my raspberry pi 3 b+, but then decided to port the whole project to a new raspberry pi zero, as I want to make it a permanent setup and want to keep my py 3 ...
1
vote
0answers
46 views

When I run the face recognition code, I get the following errors

cv2.error: OpenCV(4.0.1-dev) /home/pi/opencv/modules/highgui/src/window.cpp:610: error: (-2:Unspecified error) The function is not implemented. Rebuild the library with Windows, GTK+ 2.x or Cocoa ...
1
vote
0answers
83 views

OpenCv compilation on raspberry pi stops at 16%

I was installing OPENCV on raspberry pi and all are done but when the compilation of opencv it stops at 16%.I used make -j4 as well as make -j1.It gives no error and it comes to build folder. This is ...
1
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0answers
48 views

Raspberry camera with opencv, measure brightness

I want to build a camera with my Raspi. It should take picture whenever a face is detected. But it should give a warning when the brightness is too low for a good picture. Does anybody know a simlpe ...
1
vote
0answers
375 views

opencv cv2.imshow doesn't work

I'm working a project that getting a video from usb camera on raspi for encode qr code. So I wanna display the current frame, but i am getting this error: <cv2.imshow('Current', frame) error:/...
1
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0answers
835 views

Cant import cv2 (Model B) Python 3.5

Basically Im very new to linux systems and an, above average in python, I intended to make a program that detect hand gesture (high five , victory one,three etc) , I created my own test code that ...
1
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0answers
305 views

How to wrap a H264 stream to a MP4 container

I have successfully streamed an h264 video over the local network with this command. raspivid -o - -t 0 -n -w 1280 -h 720 -vf -vs -fps 30 -b 3500000 | cvlc -vvv stream:///dev/stdin --sout '#rtp{...
1
vote
0answers
487 views

OpenCV and PiCamera problem

I want to get photo from raspberry pi camera in python and i tried this code and it's works for me: for filename in camera.capture_continuous('img.jpg'): test_img = cv2.imread('img.jpg') But ...
1
vote
0answers
157 views

Unable to start capture: Invalid argument

Below code all are work well but when I add a code publish the live stream through dataplicity. There will occur error "Unable to start capture: Invalid argument i: Error grabbing frames". After the ...
1
vote
0answers
221 views

What is the camera matrix for picamera V2.1?

As you know, all cameras have original camera matrix and distortion coefficient values. Is there any guy who had already gotten exact camera matrix of picamera V2.1?
1
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0answers
441 views

Managing employees' attendance using Face Recognition

I'm creating an employees' attendance management system using Face recognition on RPi (2 or 3). I use Python face_recognition library for face detecting and recognition. I currently think of two ways ...
1
vote
0answers
287 views

opencv workon cv doesn't work

I installed opencv on my Pi zero via SSH. And now, if I digit workon cv via SSH it works. But if I digit workon cv in a graphical session (vncserver) terminal, bash responds: no command found.. ...
1
vote
0answers
2k views

OpenCV VideoWriter and Hardware h264

I'm working on a python/pygame application, and i'm facing some difficulties when I try to capture a video from a usb camera (640x480) to a h264 encoded file, through OpenCV. Everything work fine with ...
1
vote
0answers
724 views

White Balance Drift off from Pi Camera

I'm currently trying to develop image tracking using color in Python 3 and OpenCV. But i am facing problem in PiCamera. At the moment, i've done some method to fix white balance, shutter speed, and ...
1
vote
0answers
786 views

How can I get the raspberry Pi camera working with c++ on OpenCV 3.2?

I was pleased to read about the addition of ARM support in the Opencv 3 change log, and decided to try installing OpenCV3.2 on my raspberry Pi. The installation appears to have been a success, and ...
1
vote
0answers
285 views

OpenCV without display

I am running OpenCV on my Raspberry Pi 2. I want to use the GPIO instead of the display as an output indicator. However OpenCV will not run without a display. Is there a way to fool the Raspberry Pi ...
1
vote
0answers
26 views

recording 2 videos of 2 different pictures

I'm using raspberry pi with python and I'm trying to record a video of : regular video stream a picture from that stream that showes a circle identification (using hough transform ) cv2.circle =...
1
vote
0answers
535 views

Optimization of picamera frame decoding for opencv processing

I am useing next code for frame capture: from picamera import PiCamera import utils res = (1600,1600) camera = PiCamera(resolution = res) camera.resolution = res camera.raw_format = 'rgb' camera....
1
vote
0answers
228 views

Using Raspberry Pi 2 B with Pan Tilt and OpenCV 3.0.0 for the 1st Time

I am very new to Raspberry Pi, and This is my first time using it. I have read a lot from the documentation on the official website, and I really got great things. After that I installed OpenCV 3 with ...
1
vote
0answers
136 views

Raspberry pi execution time calculated is different on the desktop terminal and command line?

Boot to desktop and boot to command line can be chosen using raspi-config. I decided to do a test to see whether my code will execute faster using the command line interface. How come the raspberry ...
1
vote
0answers
405 views

Unmount USB Camera

I'm working in a Python app with opencv and a USB camera. Sometimes the camera driver throws an exception: OpenCV Error: Assertion failed (scn == 3 || scn == 4) in cvtColor, file /home/pi/opencv-2....
1
vote
0answers
446 views

Trying to render image from grayscale camera with OpenCV in C++. Hangs after a few frames

have a grayscale camera (NOT COLOR) and am trying to render the image. I am running on Raspbian, on a Raspberry Pi 2. I've grabbed some code and bared it to a minimum and made some progress: #include ...
1
vote
0answers
646 views

Multiple webcams - cannot open in openCV & corrupted image

I've connected four USB webcams via well powered USB hub to RasPi2. I want to use them in openCV. So I setup a simple program, where I opened the cameras using cvCaptureFromCAM, captured a cv::Mat and ...
1
vote
0answers
300 views

Webcam doesn't work on Raspberry Pi VIDIOC-QUERYMENU: Invalid Argument

So I wrote an image processing program in Python on my windows computer and it works fine there, but when I try to run it on the Raspberry Pi I get VIDIOC-QUERYMENU: Invalid Argument a bunch of times. ...
1
vote
0answers
750 views

RPi2 Or ODROID-C1 for better OpenCV performance?

I am planning for a project requiring face recognition using OpenCV and got confused between two boards at same price - the Raspberry Pi 2 and ODROID-C1. My question is which board is more suitable (...
1
vote
0answers
2k views

How do I increase the speed of my Python OpenCV program?

Specs: RPi 2, not overclocked, did rpi-upgrade, using ssh to run vnc on laptop. I've got a face tracking algorithm that is working fine on the Pi (and my PC). Problem is it has a lag of about 2 ...
1
vote
0answers
5k views

H264 IP camera stream by Raspberry Pi 2 with OpenCV and GStreamer: Gstreamer unable to start pipeline

I'm trying to get working OpenCV with GStreamer to get IP camera rtsp stream. But it is giving error which is (with opencv-master branch, Gstreamer 1.2.4, Raspbian 3.18.7-v7+: GStreamer Plugin: ...
1
vote
0answers
455 views

Raspberry Pi + Qt4 + Opencv cross compile from windows

Hi I want to know how to use opencv in raspberry pi. I have cross compiled qt raspberry from windows and succeed but I cannot add library opencv.
1
vote
0answers
558 views

opencv and cv2.so/libcv2.so setup for python

I installed opencv 2.4.8 on my raspberry-pi. But i am not able to locate cv2.so /libcv2.so so that whenever i import i get error as cv2 not found. Is there a way to download theese packages to use in ...
1
vote
0answers
1k views

Installing openCV on raspberry pi for video detection error avformat.h not found

I want to install opencv on the raspberry pi for image detection on a video I have followed this tutorial but the videos are not to be played or proccessd. I tried to install it again to make sure ...
0
votes
0answers
14 views

RPi camera OCR,and save output in variable (pyhton with tesseract)

I want to make a python code for the raspberry pi, with the tesseract OCR engine, that it keeps reading text from the camera in realtime, saves in a variable, and sends output to Arduino. Is there a ...
0
votes
0answers
20 views

Video streaming from Raspberry PI - Python vs. raspivid + netcat

Some time ago I posted the following post on Stack Overflow, but I got no reply. I can't figure out where the additional lag with the Python method comes from. The netcat method is really smooth with ...
0
votes
0answers
12 views

OpenCV 3.3.0 issue

Hey when i am running code i got this annoying error #!/usr/bin/env python import numpy as np import cv2 as cv import os from pantilthat import * os.system('sudo modprobe bcm2835-v4l2') cascade = ...
0
votes
0answers
6 views

Using Cakephp running python tensorflow

The program is work in Raspberry Pi using Rasbian Stretch. I have python script with TensorFlow object detection. Now I am using CakePHP to implement the website. In the CakePHP, I want to run the ...
0
votes
0answers
48 views

Raspberry Pi shows 100% CPU usage then crashes when I run a python script

Hi I've been working an opencv and python project which the raspi should detect and recognize a face and detect a motion. It works fine with my laptop but after I run it on my raspi the raspi crashes. ...
0
votes
0answers
25 views

A way to synchronise image stream on multiple pis

I am trying to send a sequence of images from a "master" pi to two other pis on the same network. Each "slave" pi will need to receive a different image from the "master" pi but the two images will ...
0
votes
0answers
70 views

Tensorflow object detection script is being killed by system

I'm trying to run an object detection script using Tensorflow. After running the python script it's being killed or freezes. I can see camera's light is being turned on right before the script stops. ...
0
votes
0answers
13 views

gpiozero ImportError in virtual environment

I've been trying to use the gpiozero library lately with one of my opencv projects. Installed gpiozero using pip. Sample code works fine, no issues. The problem is, my opencv installation is in a ...
0
votes
0answers
100 views

Executing a opencv python2 script from SSH Putty console

I try to execute a python2 script which is supposed to display a movie file. When I execute this code with VNC it works, I can see the movie being played (eventhough the fps is limitted around 2...) ...