Image Processing: Edge detection of the tumor on tomogram. Сalculation area of the tumor

Question

The task is to identify the image region of the tumor.

I try to use example from documentation centre:

tom1 = Import["https://i.sstatic.net/mZ4fR.jpg"];
tumor = SelectComponents[
          DeleteBorderComponents[ Binarize[ tom1, {0.75, 1}]], 
          {"Area", "Holes"}, 2800 < #1 < 2900 && #2 > 0 &];
circle = ComponentMeasurements[ 
           ImageMultiply[ tom1, tumor], 
           {"Centroid", "EquivalentDiskRadius"}][[All, 2]];
Show[ tom1, Graphics[{Red, Thick, Circle @@ # & /@ circle}]]

but get unsatisfactory result:

i try to identify tumor like this but selection was noisy:

SelectComponents[
  DeleteBorderComponents[ Binarize[ tom1, {0.75, 1}]], 
  {"Area", "Holes"}, 2800 < #1 < 2900 && #2 > 0 &]

So, can you help me to make clearer allocation of the tumor and then calculate the area of ​​selection?

Answer 1

Your approach is quite good. I would smooth the data a bit and do an Opening to cut one extra part:

tom1 = Import["https://i.sstatic.net/mZ4fR.jpg"];
smooth = GaussianFilter[tom1, 2];
tumor = SelectComponents[
  DeleteBorderComponents[
   Opening[Binarize[smooth, {0.8, 1}], 1]], {"Area", "Holes"}, 
  2000 < #1 < 2200 &];

HighlightImage[tom1, tumor]

And for the second part of your question, you can then use, as pointed out by bobthechemist

ComponentMeasurements[tumor, "Area"]
(* {1 -> 2062.} *)