+open("http://www.antweb.org/images/casent0249453/casent0249453_h_1_high.jpg");

+//open("http://www.antweb.org/images/casent0902634/casent0902634_h_1_high.jpg");

+

+title=getTitle();

+getDimensions(width, height, channels, slices, frames);

+

+//-- duplicate the bottom right of the image to try and find the scale bar

+makeRectangle(width-floor(width*0.4), height-150, floor(width*0.4), 150);

+run("Duplicate...", "title=scale");

+run("8-bit");

+run("Median...", "radius=1");

+//setThreshold(0, 30);

+setAutoThreshold("Default light");

+

+setOption("BlackBackground", true);

+run("Convert to Mask");

+run("Analyze Particles...", "size=100-Infinity show=Masks clear add in_situ");

+

+//-- for each object check concavity or solidity

+numObj=roiManager("count");

+//-- record the squareness and the width

+squareness=newArray(numObj);

+sqW=newArray(numObj);

+for (i = 0; i < numObj; i++) {

+	roiManager("select", i);

+	//--calculate "squareness"

+	List.setMeasurements;

+	sqW[i]=List.getValue("Width");

+	//-- don't really need this other than to calculate the bounding box so replace every loop

+	sqH=List.getValue("Height");

+	squareness[i]=List.getValue("Area")/(sqW[i]*sqH);

+}

+//Array.print(squareness);

+//-- Rank the array from highest squareness to lowest

+squarenessRank=Array.reverse(Array.rankPositions(squareness));

+

+//-- may want to check that the squareness is above, eg. 0.96

+

+//-- now pull the width to use for calibration

+calibVal=sqW[squarenessRank[0]];

+//Array.print(squarenessRank);

+close("scale");

+selectWindow(title);

+run("Select None");

+

+//-- Set the scale on the origial 

+run( "Set Scale...", "distance=" + calibVal + " known=1 unit=mm" );

+

+//-- add the scale bar as an overlay

+roiManager("select", squarenessRank[0]);

+getSelectionBounds(sbX, sbY, sbW, sbH);

+makeRectangle(sbX+width-floor(width*0.4), sbY+height-150, sbW, sbH);

+Overlay.addSelection("magenta", 3);