//”JStablet.jsx” by Ana Tam 2011 for use in Adobe Photoshop 
//www.anatam.co.uk/projects.html
//For re-sizing an image based on in-image scale of known color and size.
//copy and paste into text or script editor and save with .jsx extension


//Setting ruler units.  Tells app to set units as CM if it isn't already set that way.


#target photoshop


function selectBlue(){ //using eyedropper in Color Range selector


var id2382 = charIDToTypeID( "ClrR" );
    var desc488 = new ActionDescriptor();
    var id2383 = charIDToTypeID( "Fzns" );
    desc488.putInteger( id2383, 40 );
    var id2384 = charIDToTypeID( "Mnm " );
        var desc489 = new ActionDescriptor();
        var id2385 = charIDToTypeID( "Lmnc" );
        desc489.putDouble( id2385, 13.910000 );
        var id2386 = charIDToTypeID( "A   " );
        desc489.putDouble( id2386, 44.920000 );
        var id2387 = charIDToTypeID( "B   " );
        desc489.putDouble( id2387, -73.620000 );
    var id2388 = charIDToTypeID( "LbCl" );
    desc488.putObject( id2384, id2388, desc489 );
    var id2389 = charIDToTypeID( "Mxm " );
        var desc490 = new ActionDescriptor();
        var id2390 = charIDToTypeID( "Lmnc" );
        desc490.putDouble( id2390, 13.910000 );
        var id2391 = charIDToTypeID( "A   " );
        desc490.putDouble( id2391, 44.920000 );
        var id2392 = charIDToTypeID( "B   " );
        desc490.putDouble( id2392, -73.620000 );
    var id2393 = charIDToTypeID( "LbCl" );
    desc488.putObject( id2389, id2393, desc490 );
executeAction( id2382, desc488, DialogModes.NO );
}


function getSelectionBounds (doc) { //alternative to using bounds function


var l = srcDoc.artLayers.add(); 
srcDoc.selection.fill(app.foregroundColor); 
var bnds = l.bounds; 
var hs = srcDoc.historyStates; 
        if (hs[hs.length-2].name == "Layer Order") { 
        srcDoc.activeHistoryState = hs[hs.length-4]; 
        } else { 
        srcDoc.activeHistoryState = hs[hs.length-3]; 
        } 


        for (var i = 0; i < bnds.length; i++) { 
        bnds[i] = bnds[i].value; 
        } 
return bnds; 
}; 




//script work starts


var strtRulerUnits = app.preferences.rulerUnits;
if (strtRulerUnits != Units.CM)
{
  app.preferences.rulerUnits = Units.CM;
}




// Pops open a dialog for the user to choose the folder of documents to process
var inputFolder = Folder.selectDialog("Select a folder of documents to process");




// Pops open a dialog for the user to set the output folder
var outputFolder = Folder.selectDialog("Select a folder for the output files");


// see if we got something interesting from the dialog 
if (inputFolder != null && outputFolder != null)


//function openAllInFolder(){
 //Get all the files in the folder \
        var fileList = inputFolder.getFiles() // open each file  \
        for (var i = 0; i < fileList.length; i++) { 
 // The fileList is folders and files so open only files \
        if (fileList[i] instanceof File && fileList[i].hidden == false) { 


//source document
        var srcDoc = open(fileList[i]) 


//openAllInFolder()




//define target resolution - this is a fixed quantity
var n = 300; //resolution in dpi


selectBlue()




//<CS4 only> var BlueSquare = activeDocument.selection.bounds;
//for other versions using the function above to get the selection bounds
var BlueSquare = getSelectionBounds()


var horizBlue = BlueSquare[2] - BlueSquare[0];//lower right corner x - upper left corner x value
var vertBlue = BlueSquare [3] - BlueSquare[1];//lower right corner y - upper right corner y value




if ((horizBlue / vertBlue) > 1)  // it really is around 1.33; then 5cm scale
{ 
var c =(0.77/horizBlue);//target size in cm / actual size


}


else //((horizBlue / vertBlue) < 1) // it really is around 1; then 2cm scale
{
var c = (0.3 / horizBlue);
}


//only works if image is rotated correctly, e.g. not on its side




//resize image into pixel count defined by "n" - required so that resize using pixels works properly
srcDoc.resizeImage(null,null,n,ResampleMethod.BICUBIC);


var scale = (c * srcDoc.width*n/2.54);//new size of image in pixels - 2.54 to convert dpi into pixels/cm




srcDoc.resizeImage(UnitValue(scale,"px"),null,null,ResampleMethod.BICUBIC);


//saveAs(saveIn, options, asCopy, extensionType)
TiffSaveOptions = new TiffSaveOptions(); 
{
TiffSaveOptions.imageCompression = TIFFEncoding.TIFFLZW
}
srcDoc.saveAs(outputFolder,TiffSaveOptions,false,Extension.LOWERCASE);
srcDoc.close(SaveOptions.DONOTSAVECHANGES)
}
}