Need some help regarding color detection and it's position

7 次查看（过去 30 天）
i Venky
i Venky 2012-1-13
编辑： DGM 2023-2-14
I want to detect the color and it's position in an image. I don't get the output. I would be really happy if you could guide me.
Example: Take a red box in a white background at some position. I want to detect the red color and it's position (i.e. co-ordinates) in the image.
Thanks in advance.

请先登录，再回答此问题。

采纳的回答

Chandra Kurniawan
Chandra Kurniawan 2012-1-14
Hi, i Venky
from my previous post, I've improved the code.
This picture below is test image :
Here the code :
Irgb = imread('multiplecolors.jpg');
Ihsv = rgb2hsv(Irgb);
low = 0;
high = 0.04;
h = (Ihsv(:,:,1) >= low) & (Ihsv(:,:,1) <= high);
s = (Ihsv(:,:,2) >= 0.9) & (Ihsv(:,:,2) <= 1);
v = (Ihsv(:,:,3) >= 0) & (Ihsv(:,:,3) <= 1);
mask = uint8(h & s & v);
mask = imclose(mask, strel('disk', 5));
mR = mask .* Irgb(:,:,1);
mG = mask .* Irgb(:,:,2);
mB = mask .* Irgb(:,:,3);
Icolor = cat(3, mR, mG, mB);
Igray = rgb2gray(Icolor);
Ibw = im2bw(Igray,graythresh(Igray));
Ilabel = bwlabel(Ibw);
stat = regionprops(Ilabel,'boundingbox','centroid');
imshow(Irgb); hold on;
for x = 1 : length(stat)
bb = stat(x).BoundingBox;
xc = stat(x).Centroid(1);
yc = stat(x).Centroid(2);
txt = sprintf('x : %.2f\ny : %.2f',xc,yc);
rectangle('position',bb,'edgecolor','b','linewidth',2);
plot(xc,yc,'bo');
text(xc,yc+30,txt,'color','y','fontweight','normal');
end
And the result shown below :
The pink colored object is not detected anymore.
It is so simple like I said. Just adjusting the values of hue, saturation, intensity.
  9 个评论
显示 7更早的评论
jyothi
jyothi 2014-5-14
hey thank u very much then what are the values for other different colors
Image Analyst
Image Analyst 2014-5-14
Extract them, then enter in a location and find out:
% Extract the individual red, green, and blue color channels.
redChannel = rgbImage(:, :, 1);
greenChannel = rgbImage(:, :, 2);
blueChannel = rgbImage(:, :, 3);

请先登录，再进行评论。

更多回答（1 个）

Walter Roberson
Walter Roberson 2012-1-13
You have already been guided in your previous copy of this question.
In order to be guided further, you need to answer the question there as to how exactly you define each color.

类别

在 Help Center 和 File Exchange 中查找有关 Image Processing Toolbox 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by