How to apply fluorescent filtering on an already working edge detection code?

3 次查看（过去 30 天）
Ben Timm
Ben Timm 2020-7-11
评论： Image Analyst 2020-7-18
Hi all, back again!
I have a really great piece of code for edge detection (see attached) however prior to getting it working, my previous code created fluorescent style images such as attached. The code for it is seen here:
"
Function Vid_Edge_Detection_flourescent
v = VideoReader('VID00125.AVI');
n = v.NumFrames;
for i = 1:n
I0 = read(v,i);
I1 = im2bw(I0,graythresh(I0)-0.03); % binarize image with treshold
I2 = bwareaopen(I1,50); % remove small regions (50 pixels)
I3 = edge(I2);
II = imfuse(I0,I3);
imshow(II,'initialmagnification','fit')
pause(0.1)
end
end
"
From what I understand, the old code produced a double layer, the background one being altered to a green background and the forground being the edge detection. Essentially, I'm trying to get the same thing for the new attached code but because of all the for loops, I really have no idea where/what to change. Can anyone assist?
Thanks in advance,
Ben

请先登录，再回答此问题。

采纳的回答

Image Analyst
Image Analyst 2020-7-11
Not sure what you want. Do you just want the edges overlaid on the original image frames, perhaps in some specified color, like magenta? Do you want the main image converted to grayscale and then put into the green channel while the edges to into the blue and red channel? Like this:
rgbImage = cat(3, edgeImage, rgb2gray(thisFrame), edgeImage);
where thisFrame is the original RGB image, and edgeImage is a grayscale image with values of 0 and 255 only?
  6 个评论
显示 4更早的评论
Ben Timm
Ben Timm 2020-7-13
编辑：Ben Timm 2020-7-13
Apologies for the daft questions, I'm still very much new to video processing. I get why you've changed the image size but im not too sure why the rgbImage wont work, because its greyscaled?
More importatly, Ive meddled around with the for loop where I think youre suggested code is supposed to go, but it wont recognise 'rgbImage' despite me changing it. I feel that I've overlapped some old and new code but havent clicked to what it is..
"
for frame = 1 : numberOfFrames
% Extract the frame from the movie structure.
% thisFrame = read(videoReaderObject, frame);
I0 = read(videoReaderObject, frame);
rgbImage = I0;
if size(rgbImage, 3) == 3
grayImage = rgb2gray(rgbImage);
else
grayImage = rgbImage;
end
I1 = im2bw(I0,graythresh(I0)-0.03); % binarize image with threshold
I2 = bwareaopen(I1,50); % remove small regions (50 pixels)
grayImage = rgb2gray(rgbImage);
thisFrame = edge(grayImage, 'Canny');
edgeImage = imdilate(edgeImage, true(3));
edgeImage = 255 * uint8(edgeImage);
thisFrame = uint8(255 * thisFrame);
% Make RGB
thisFrame = cat(3, edgeImage, grayImage, edgeImage);
"
It simply says Unrecognized function or variable 'rgbImage'.
Error in Test_4 (line 65)
if size(rgbImage, 3) == 3
Thank you as always, youve been a great help!
Ben Timm
Ben Timm 2020-7-14
Hi again!
Still having trouble with the rbg2gray part. Though I did manage to figure out the other two sections of the cat function working (see below). Even if I change the final, middle part to grayImage instead of rgb2gray, it wont work. Could I ask what the appropriate lines are to get the correct background?
% Extract the frame from the movie structure.
% thisFrame = read(videoReaderObject, frame);
I0 = read(videoReaderObject, frame);
I1 = im2bw(I0,graythresh(I0)-0.03); % binarize image with threshold
I2 = bwareaopen(I1,50) ; % remove small regions (50 pixels)
%edgeImage = edge(grayImage, 'Canny');
I3 = edge(I2);
% Thicken the edges a bit to make them more visible.
thisFrame = I3;
thisFrame = imdilate(I3, true(3));
% Make uint8
thisFrame = uint8(255 * thisFrame);
rgbImage = I0;
if size(rgbImage, 3) == 3
grayImage = rgb2gray(rgbImage);
else
grayImage = rgbImage;
end
% Make RGB
thisFrame = cat(3, I3, rgb2gray(thisFrame), I3);

请先登录，再进行评论。

更多回答（1 个）

Ben Timm
Ben Timm 2020-7-16
编辑：Image Analyst 2020-7-16
Figured it out for future users. You simply change the middle thisFrame to grayImage as seen below:
thisFrame = cat(3, thisFrame, (grayImage), I3);
The bold ones can seemingly change the the colour of the edge detection lines, will definitely play around with it more.
Once again thank you for the assistance Image Analyst, couldn't have done it without you.
  4 个评论
显示 2更早的评论
Ben Timm
Ben Timm 2020-7-18
Back again! Thought it was probably best to comment on this again to save time. It seems that once I run the code it works up until the prompt "Do you want to recall the individual frames as a movie". Which then works for a certain number of frames within the video (this varies) and then produces this error:
"
Error using VideoWriter/writeVideo (line 368)
Frame must be 964 by 544
Error in Test_3 (line 284)
writeVideo(videoWriterObject, thisFrame);
"
I have absolutely no clue why it is doing this despite efforts to find out. Could you/anyone else advise?
See attached for the file. Any AVI should work, thanks as always..
Image Analyst
Image Analyst 2020-7-18
It's probably recalling a still image that's not the same size as the others that it has been using to build the movie with so far. Check the size of thisFrame and see what it is for each frame, like
fprintf('For %s\n Frame #%d, rows = %d, columns = %d\n', ...', ...
outputFullFileName, frame, size(thisFrame, 1), size(thisFrame, 2));
When if throws the error, look in the command window for what it said for all the frames up to that point.

请先登录，再进行评论。

类别

在 Help Center 和 File Exchange 中查找有关 Watermarking 的更多信息

标签

产品

Community Treasure Hunt

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

Start Hunting!

Translated by