problem in cvtColor function
Hi,I have a native methode which play frame so i retreive the pixels of the image into a byte [] buffer and call a java methode to proceed the processing : public void processCameraImage(byte[] buffer,...
View Articlebuilding photoshop-style black-white-conversion
Hi all! I'm trying to separate some coloured object from my background. Before starting with OpenCV I'm using a test image in Photoshop to check which color channels or which combination of color...
View ArticleGrayscale to Lbp image
[Actual output](/upfiles/137882303996361.png) [Desired output](/upfiles/13788229926776895.jpg) Hi friends i am trying to implement paper on Rapid texture Based Moving Object Detection So in this the...
View Articlebgr image grayscale
I want to develop some color to grayscale algorithms in order to get an idea about how important a grayscale algorithm could be for feature extraction methods (lbp, hog, ...) and object recognition...
View ArticleSelect only gray pixels in color image
Hi To aid my OCR component in recognizinig text I'd like to binary threshold my image first. I'd like to try a new method of thresholding where I do not only define a threshold value, but als define...
View ArticleHow to convert ROI in gray (monochrome) on android?
Hello. How to convert ROI in gray (monochrome) on android? I try that, but it does not work: public Mat onCameraFrame(CvCameraViewFrame inputFrame) { Mat image = inputFrame.rgba(); Rect roi = new...
View ArticleHi we are beginner with opencv and we would like to obtain the code of the...
In matlab, I used imfill (img2 = imfill(img,'holes')) to the image to fill the holes in a gray image and we don't know how to use her in opencv 2.2. Help us please.
View Articlehow to know grayscale or color img loaded
I need to know, is loaded img grayscale or color to not process grayscale. My idea is get grayscale by cvtColor(src,src_gray,COLOR_BGR2GRAY) and compare with loaded img. Perhaps there is a standard or...
View Articlefastest way to access individual bytes in CV_8U1
I am hoping to squeeze every ounce of speed from opencv videocapture. Can someone please enlighten me as to whether there is a better method to access individual pixel grayscale values as i iterate...
View Articlefalse coloring of grayscale image
Hello, I have a grayscale image to which I want to apply false coloring. Below is a chunk of my code where I loop through all rows and cols of my matrix (matProcessed). For each pixel value, I lookup...
View ArticleGrayscale image instead of RGB image
Help me, please. I have 3 color components. When I merging them(function merge()) and then read matrix to image and save them on disk(function imread()), I get grayscale JPEG image instead of color...
View ArticleImproving line extraction from HoughLinesP
Hi, I am using `HoughLinesP` to extract lines from grayscale image. Below is my psudo code. threshold(img_tmp,bin_img,30,255,cv::THRESH_BINARY); Canny(bin_img, canny_img, 50, 255, 3); vector...
View ArticleHow to calculate the YUV values of a grayscale image ?
Is it possible to calculate the values YUV of a graycale image ? I found an article that confuses me: ***Interactive Image Colorization and Recoloring based on Coupled Map Lattices*** In which the...
View ArticleYUV values in grayscale images
YUV color space equations are done by:  This leads to: Y=(0.492*B - U)/0.492 Y=(0.877*R - V)/0.877 In...
View ArticleGrayScale Vs YUV comparaison
In some comments on previous questions, people told me that `Y` value of a `YUV` image converted using: image_in_yuv=cv2.cvtColor(image_in_bgr,cv2.COLOR_BGR2YUV) is the same as the L value of the same...
View ArticleConvert CV_16UC3 color image to CV_8U grayscale
Hi I'm trying to convert a CV_16UC3 color image to a CV_8U grayscale image. However, the cvtColor function does not accept CV_16UC3 input images. How could I do the desired conversion?
View Articlecustom grayscale conversion
I'm trying to improve my edge detection and found out, what is logical: some edges are detected better in the red channel, others in the green etc. I would like to use only one Canny-call and not three...
View ArticleMetal Edge Defect Detection
Hi, Need help in finding defects in metal(steel or aluminum) edge. Images are in gray scale, with edge in black background. If there is an impression formed by the improper cut of the edge, the images...
View ArticleGrayscale image conversion error in eclipse
I created an eclipse project according to the instructions found in [here](http://docs.opencv.org/3.0-beta/doc/tutorials/introduction/linux_eclipse/linux_eclipse.html#linux-eclipse-usage), and...
View ArticleCamShift on grayscael
Hi, I would like to use Camshift to track the head and retrieve the roll angle like this. Is there a way to use CamShift on a grayscale image? I'm using a Time-of-flight camera and I can only get a...
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