How to get Brightness/Contrast levels of a layer, using .jsx Adobe Photoshop scripting?

[antond99983697]

I have a .jsx Photoshop script workflow that begins by first applying a Brightness/Contrast adjustment to the current image, then uses the "Auto" setting.

For the next step, I'd like to get the properties of that Brightness/Contrast layer, and then IF the brightness meets a certain criteria? Change the brightness to some other value. Same for the contrast.

What's the best way to automate this in my .jsx file?

Thanks!

[c.pfaffenbichler]

You should be able to get the Layer’s settings via AM-code. 

[Stephen_A_Marsh]

@c.pfaffenbichler - Easier said than done, at least for me!

[antond99983697]

Any idea what that code would look like? I tried for HOURS yesterday and just couldn't get it to work. Kept throwing errors. Here's one I tried that outputs a Photoshop general error:

    var ref = new ActionReference();

    ref.putEnumerated(charIDToTypeID("Lyr "), charIDToTypeID("Ordn"), charIDToTypeID("Trgt"));

    var desc = executeActionGet(ref);

    var adjs = desc.getList(charIDToTypeID("Adjs"));

    var brConDesc = adjs.getObjectValue(0);

    var brightness = brConDesc.getInteger(charIDToTypeID("Brgh"));

    var contrast = brConDesc.getInteger(charIDToTypeID("Cntr"));

    alert("Brightness: " + brightness + "\nContrast: " + contrast);

[r-bin]

Any idea what that code would look like? I tried for HOURS yesterday and just couldn't get it to work. Kept throwing errors.

By @antond99983697

It would be better if you looked at the topics nearby or used the search.

[antond99983697]

adj.brightness is showing up as undefined when I run this function. Not sure why because the active layer should be a Brightness/Contrast layer.

    // Apply auto brightness/contrast adjustment

    var autoDescriptor = new ActionDescriptor();

    var reference = new ActionReference();

    reference.putClass(stringIDToTypeID("adjustmentLayer"));

    autoDescriptor.putReference(stringIDToTypeID("null"), reference);

    var typeDescriptor = new ActionDescriptor();

    var brightnessDescriptor = new ActionDescriptor();

    brightnessDescriptor.putBoolean(stringIDToTypeID("auto"), true);

    brightnessDescriptor.putBoolean(stringIDToTypeID("useLegacy"), false);

    typeDescriptor.putObject(stringIDToTypeID("type"), stringIDToTypeID("brightnessEvent"), brightnessDescriptor);

    autoDescriptor.putObject(stringIDToTypeID("using"), stringIDToTypeID("adjustmentLayer"), typeDescriptor);

    var resultDesc = executeAction(stringIDToTypeID("make"), autoDescriptor, DialogModes.NO);

    var ref = new ActionReference();

    ref.putEnumerated(charIDToTypeID('Lyr '), charIDToTypeID('Ordn'), charIDToTypeID('Trgt')); // reference is active layer

    var layerDesc = executeActionGet(ref);

    var layerID = layerDesc.getInteger(stringIDToTypeID('layerID'));

    // Use the function you found to get the brightness descriptor

    var brConDesc = get_contrast_desc(layerID);

function get_contrast_desc(id) {

    try {

        var r = new ActionReference();

        var d = new ActionDescriptor();

        r.putProperty(stringIDToTypeID("property"), stringIDToTypeID("json"));

        r.putEnumerated(stringIDToTypeID("document"), stringIDToTypeID("ordinal"), stringIDToTypeID("targetEnum"));

        d.putReference(stringIDToTypeID("null"), r);

        d.putInteger(stringIDToTypeID("layerID"), id);

        d.putBoolean(stringIDToTypeID("layerInfo"), true);

        d.putBoolean(stringIDToTypeID( "includeAncestors" ), false);

        eval("var json="+executeAction(stringIDToTypeID("get"), d, DialogModes.NO).getString(stringIDToTypeID("json")));

        var d = new ActionDescriptor();

        if (!json.layers) return d;

        if (json.layers.length != 1) return d;

        if (json.layers[0].id != id) return d;

        var adj = json.layers[0].adjustment;

        alert(adj.brightness); // shows undefined, even though the active layer is a Brightness/Contrast layer

        if (!adj) return d;

        if (adj.brightness != undefined) d.putInteger(stringIDToTypeID("brightness"), adj.brightness);

        if (adj.center     != undefined) d.putInteger(stringIDToTypeID("center"),     adj.center);

        if (adj.useLegacy  != undefined) d.putBoolean(stringIDToTypeID("useLegacy"),  adj.useLegacy);

        return d;

        }

    catch (e) { throw(e); }

}

[r-bin]

Yes, cool. Photoshop never ceases to please with its bugs. This is all due to the use of the "Auto" button.

Here is a crutch that fixes a bug.

// Apply auto brightness/contrast adjustment
    var autoDescriptor = new ActionDescriptor();
    var reference = new ActionReference();
    reference.putClass(stringIDToTypeID("adjustmentLayer"));
    autoDescriptor.putReference(stringIDToTypeID("null"), reference);
    var typeDescriptor = new ActionDescriptor();
    var brightnessDescriptor = new ActionDescriptor();
    brightnessDescriptor.putBoolean(stringIDToTypeID("auto"), true);
    brightnessDescriptor.putBoolean(stringIDToTypeID("useLegacy"), false);
    typeDescriptor.putObject(stringIDToTypeID("type"), stringIDToTypeID("brightnessEvent"), brightnessDescriptor);
    autoDescriptor.putObject(stringIDToTypeID("using"), stringIDToTypeID("adjustmentLayer"), typeDescriptor);
    var resultDesc = executeAction(stringIDToTypeID("make"), autoDescriptor, DialogModes.NO);

    ///////////////////////////////////////////////////////////////////////////////////////////
    // idle correction change so that photoshop removes the "auto" parameter from the adjustment object.
    var d = new ActionDescriptor();
    var r = new ActionReference();
    r.putEnumerated(stringIDToTypeID("adjustmentLayer"), stringIDToTypeID("ordinal"), stringIDToTypeID("targetEnum"));
    d.putReference(stringIDToTypeID("null"), r);
    var data = new ActionDescriptor();
    d.putObject(stringIDToTypeID("to"), stringIDToTypeID("brightnessEvent"), data);
    executeAction(stringIDToTypeID("set"), d, DialogModes.NO);
    ///////////////////////////////////////////////////////////////////////////////////////////


    var ref = new ActionReference();
    ref.putEnumerated(charIDToTypeID('Lyr '), charIDToTypeID('Ordn'), charIDToTypeID('Trgt')); // reference is active layer
    var layerDesc = executeActionGet(ref);
    var layerID = layerDesc.getInteger(stringIDToTypeID('layerID'));

    // Use the function you found to get the brightness descriptor
    var brConDesc = get_contrast_desc(layerID);
 
function get_contrast_desc(id) {
    try {
        var r = new ActionReference();
        var d = new ActionDescriptor();

        r.putProperty(stringIDToTypeID("property"), stringIDToTypeID("json"));
        r.putEnumerated(stringIDToTypeID("document"), stringIDToTypeID("ordinal"), stringIDToTypeID("targetEnum"));
        d.putReference(stringIDToTypeID("null"), r);

        d.putInteger(stringIDToTypeID("layerID"), id);
        d.putBoolean(stringIDToTypeID("layerInfo"), true);

        d.putBoolean(stringIDToTypeID( "includeAncestors" ), false);

        eval("var json="+executeAction(stringIDToTypeID("get"), d, DialogModes.NO).getString(stringIDToTypeID("json")));

        var d = new ActionDescriptor();

        if (!json.layers) return d;
        if (json.layers.length != 1) return d;
        if (json.layers[0].id != id) return d;

        var adj = json.layers[0].adjustment;
        alert(adj.brightness); // shows undefined, even though the active layer is a Brightness/Contrast layer

        if (!adj) return d;

        if (adj.brightness != undefined) d.putInteger(stringIDToTypeID("brightness"), adj.brightness);
        if (adj.center     != undefined) d.putInteger(stringIDToTypeID("center"),     adj.center);
        if (adj.useLegacy  != undefined) d.putBoolean(stringIDToTypeID("useLegacy"),  adj.useLegacy);

        return d;
        }
    catch (e) { throw(e); }
}