To restore the original image dimension after applying masks.

Hello Sir,

How to get the original image dimension , when i apply

mask = img >= 190 & img <= 226;
img( mask) =255

my images size is 712x1825 uint8, some are greater than 3000 , matlb does give me my original size of the image,

when i resize the image" img = imresize(I, 0.4 )" after getting output of the images. I want to take the precision , recall and F_measure with ground_thruth of the dataset, it gives me the error "Matrix dimensions must agree.".. Now my question is that after apply mask how get the original size or dimension of the images???

Answer 1

[Walter Roberson]

Your code to apply the mask to img does not change the size of img.

If you need to get out something that is the size of I after you did

img = imresize(I, 0.4);
mask = img >= 190 & img <= 226;
img( mask) =255

then proceed to

img_I_sized = imresize(img, [size(I,1), size(I,2)]);

[Noor Afridi]

HI Sir,

Hope u will be fine and shine.

it givee the following warning , which effect my precision , recall and F1

"Warning: Image is too big to fit on screen; displaying at 67%

> In images.internal.initSize (line 71)

In imshow (line 337)

In color_patches (line 39) "

[Noor Afridi]

Sir,

If i wanna save the image without resizing then please tell the method how to save it without show the image in png directly using the code.

[Noor Afridi]

Thank you Sir for your help

it help me alot. i also find other solution too.

[Walter Roberson]

it givee the following warning , which effect my precision , recall and F1

That warning has absolutely no effect on your precision, recall, or F1 calculations. It is telling you that when you did the imshow() that the image was larger than your available monitor size, so it has scaled the visual image down to fit on the screen. The content of your image arrays has not been changed.

imshow() has nothing to do with saving images... not unless the way you are saving images is to imshow() and then use the menu to Save the image as a file.

If i wanna save the image without resizing

imwrite() the array. You do not need to display it to imwrite() it.

imwrite(img, 'YourOutputFileNameGoesHere.png');