How can I get the blue line in google maps screenshot? And also how can I fill the blanks in line?

I need the coordinates of the blue road in google directions. But there are gaps because there are texts in between. I can't get the only blue part. I tried to do as below.

map = imread('map3.png');
subplot(3,3,1);
imshow(map, []);

[R,G,B] = imsplit(map);
subplot(3,3,2);
imshow(R, []);

Istrech = imadjust(R,stretchlim(R));
subplot(3,3,3);
imshow(Istrech, [])
 
filteredImage = imbothat(Istrech, true(50));
subplot(3,3,4);
imshow(filteredImage, []);
 
threshold = 130;
mask = imfill(filteredImage, 'holes');
subplot(3,3,5);

imshow(mask, []);
mask2 = mask > threshold;
subplot(3,3,6);
imshow(mask2, []);
 
mask3= bwareaopen(mask2, 9);
subplot(3,3,7);
imshow(mask3, []);

mask4 = bwareafilt(mask3, 1);
subplot(3,3,8);
imshow(mask4, []);

BW2 = bwpropfilt(mask4,'perimeter',20);
subplot(3,3,9);
imshow(BW2, []);

I also need to embed this path as a MAtlab function in simulink like shown in below. How can I do that?

function y = fcn(u)

y = u;

Answer 1

[Image Analyst]

Use the Color Thresholder tool on the Apps tab of the tool ribbon.

See attached demo.

[Zeynep Calik]

its very helpful thanks

but Is there a way to fill the blanks?

Answer 2

[Image Analyst]

Well you could try imclose() though that may change the shapes slightly. Or you could try searching for edge linking routines. See link and attachment, and do a web search yourself.

https://www.peterkovesi.com/matlabfns/#edgelink