testImageIdx $=$ randi$([1,3])$

testCoinImage $=$ imread$("$testCoinImage$"+$testImageIdx$+".$png$")$;

title$("$Original Coin Image"$)$;

$[$testcoinMask$,$MaskedtestCoin$]=$ segmentCoin$($testCoinImage$)$;

$\%$ Shrink the coin mask.

se $=$ strel$(\text{'}$disk$\text{'},20,0)$;

testcoinMask $=$ imfill$($testcoinMask$,$ 'holes'$)$; $\%$ Fill any holes in it$.$

testcoinMask $=$ imerode$($testcoinMask$,$ se$)$; $\%$ Shrink by $3$ layers of pixels.

$\%$ Find edges using original poster's code.

imgFilt $=$ imgaussfilt$($MaskedtestCoin$,0\mathrm{.}5,...$

Padding$=$"circular",FilterDomain$=$"frequency",FilterSize$=3)$;

faceEdgeMask $=$ edge$($imgFilt$,$"sobel",$0\mathrm{.}05,$"both"$)$;

$\%$ Erase outside the shrunken coin mask to get rid of outer boundary.

faceEdgeMask$($~testcoinMask$)=$ false;

imshow$($faceEdgeMask$)$;

title$("$Edge Mask Detection for Valid Coins"$)$

se $=$ strel$(\text{'}$disk$\text{'},5)$; $\%$ You can adjust the disk size based on your requirements

dilatedFaceEdgeMask $=$ imdilate$($faceEdgeMask$,$ se$)$;

$\%$ Step $5$: Logical combination of dilated face edge mask and foreground mask

validCoinMask $=$ dilatedFaceEdgeMask & testcoinMask;

$\%$ Step $6$: Display the original image, testCoinMask, faceEdgeMask, and validCoinMask

figure;

subplot$(2,2,1)$; imshow$($testCoinImage$)$; title$(\text{'}$Original Image'$)$;

subplot$(2,2,2)$; imshow$($testcoinMask$)$; title$(\text{'}$Foreground Mask'$)$;

subplot$(2,2,3)$; imshow$($faceEdgeMask$)$; title$(\text{'}$Face Edge Mask'$)$;

subplot$(2,2,4)$; imshow$($validCoinMask$)$; title$(\text{'}$Valid Coin Mask'$)$;

$\%$ Step $7$: Save the validCoinMask for further analysis or evaluation

save$("$validCoinMask$.$mat", "validCoinMask"$)$;

function $[$testcoinMask$,$MaskedtestCoin$]=$ segmentCoin$($X$)$

$\%$segmentImage Segment image using auto$-$generated code from Image Segmenter app

$\%[$BW$,$MASKEDIMAGE$]=$ segmentImage$($X$)$ segments image X using auto$-$generated

$\%$ code from the Image Segmenter app. The final segmentation is returned in

$\%$ BW$,$ and a masked image is returned in MASKEDIMAGE.

$\%$ Auto$-$generated by imageSegmenter app on $31-$Dec$-2022$

$\%----------------------------------------------------$

X $=$ im$2$gray$($X$)$;

$\%$ Threshold image $-$ manual threshold

testcoinMask $=$ im$2$gray$($X$)>150$;

$\%$ Close mask with default

radius $=12$;

decomposition $=4$;

se $=$ strel$(\text{'}$disk$\text{'},$ radius, decomposition$)$;

testcoinMask $=$ imclose$($testcoinMask$,$ se$)$;

$\%$ Create masked image.

MaskedtestCoin $=$ X;

MaskedtestCoin$($~testcoinMask$)=0$;

end

this is my code for the valid coin segmentations

testImageIdx $=$

$2$

Figure $2$ of $2$

the error imgetting is :

Assessment result: incorrectIs the valid coin mask correct?

Your coin mask is not capturing the full area of all valid coins.