Creating a custom gradient from Sample Image

[Jason Burnett]

I have a simple noise-like gradient with lot of stops. I need a script that will sample each column of my document to get the color and add a stop to a gradient with that color. The end result would be a gradient fill pattern that matched the gradient in my image.

Ultimately, I want to use this new gradient to do a gradient map on a separate image.

This seems like it would be pretty easy to do, but I am having a hard time understanding JS in Photoshop...even with scriptListener installed. 

Any help would be greatly appreciated.

[Jason Burnett]

I am trying to figure out the Photoshop DOM and it seems really strange to me. Here is some basic pseudocode that I thought I could just modify to work with PS, but it is not that easy I am finding.

let doc=document; //grab a reference to the current document
let cols=doc.getColumns(); //grab an array of references for 1px wide columns for the document;

let stops=[]; //these will be the gradient stops
let colCount=cols.length; //get the total count of columns
for (let colNum=0;colNum<colCount;colNum++) { //iterate through columns
    let theCol=cols[colNum]; //grab a reference to the column
    let colColor=getColorValue(theCol,[0,0]); //sample the top pixel in the column
stops.push({color:createColor(colColor), pos:createPos(colNum, colCount)});//push the color and the stop pct
}
let props={name:"testGradient"} //set any properties needed here
let grad=new PSgradient(props, stops); //creates the new gradient fill.
doc.addFill(grad); //adds the new gradient fill to the document

function getColorValue(colRef,pixelPos) {
//whatever it takes to sample the color of a column reference at a coordinate
}
function createColor(colorRef) {
    //whatever it takes to define a color in photoshop

}
function createPos (stopNum, stopCount) {
    return stopNum/stopCount; //may need to have integer stop percentages?
}

[erinferinferinf]

The Photoshop DOM is indeed very confusing... 

ScriptListener is rapidly becoming the old way of doing things. You might give the Alchemist plugin a try... here's a video about it: https://www.davidebarranca.com/development/adobe-uxp-things-you-need-to-know-7-batchplay-part-2-alch...