Create one-color jpgs from csv file

Thank you for your help! I just tried the script and when I use 8-bit PNGs there are color shifts. As long as I use 24-bit PNGs no color shifts accure. I also adjustet some parameters:

//the save for web PNG Options 
var so = new ExportOptionsSaveForWeb();
so.format = SaveDocumentType.PNG;
so.PNG24 = true;

app.preferences.rulerUnits = Units.PIXELS;

var w = 1080;
var h = 1080;
var r = 96;

 As a result I get a 2kb PNG with no colorshifts.

Do you get the same results using the adjusted script or am I missing something which can cause some problems?

Most likely the problem is that JPEG is not the best format for storing accurate color values. JPEG uses the YCbCr color space, i.e. all colors of your image are converted into it before saving. Since JPEG was originally conceived as a lossy format, due to limited computational accuracy, not all colors can be converted correctly.

For example, if we perform operations without rounding, then after converting RGB-> YCbCr-> RGB:

/*
	BT.601	BT.709	BT.2020
a	0.299	0.2126	0.2627
b	0.587	0.7152	0.6780
c	0.114	0.0722	0.0593
d	1.772	1.8556	1.8814
e	1.402	1.5748	1.4747
*/

makeRGB('010093')

function makeRGB(a) {
    var colorobj = new RGBColor();
    colorobj.hexValue = a;

    with (colorobj) {
        var Y =0.2627 * red + 0.6780 * green + 0.0593 * blue,
            Cb = (blue - Y) / 1.8814,
            Cr = (red - Y) / 1.4747;

        red = Y + 1.4747 * Cr
        green = Y - (0.2627 * 1.4747 / 0.6780) * Cr - (0.0593 * 1.8814 / 0.6780) * Cb
        blue = Y + 1.8814 * Cb

    }
$.writeln (colorobj.hexValue)
};

we get the same color:

Result: 010093

But if we round up the values during conversion:

/*
	BT.601	BT.709	BT.2020
a	0.299	0.2126	0.2627
b	0.587	0.7152	0.6780
c	0.114	0.0722	0.0593
d	1.772	1.8556	1.8814
e	1.402	1.5748	1.4747
*/

makeRGB('010093')

function makeRGB(a) {
    var colorobj = new RGBColor();
    colorobj.hexValue = a;

    with (colorobj) {
        var Y = Math.round(0.2627 * red + 0.6780 * green + 0.0593 * blue),
            Cb = Math.round((blue - Y) / 1.8814),
            Cr = Math.round((red - Y) / 1.4747);

        red = Math.round(Y + 1.4747 * Cr)
        green = Math.round(Y - (0.2627 * 1.4747 / 0.6780) * Cr - (0.0593 * 1.8814 / 0.6780) * Cb)
        blue = Math.round(Y + 1.8814 * Cb)

    }
$.writeln (colorobj.hexValue)
};

we get exactly the color that you see after opening the file:

Result: 020092

We could assume that only Photoshop does this, but no, it looks like rounding is spelled out in the standard. I generated a tiff file with color # 010093 and tried converting it in various programs (including ImageMagik, which is famous for its exact adherence to all standards) - in all cases I got a JPG with color # 020092

So, I recommend using a different image format.

You can read and write files with javascript. You should be able to read your CSV file in a Photoshop script.

This Photoshop will read its temp files in your system  temp space and display its content.  If the File does not exists it will create the file when you run it.  So if you  run the script it will both write and read the file.

#target photoshop
app.bringToFront();



//Set First Time Defaults here
var dfltCpys = 12;	// default number of copies including the original
var dfltPos = 4;	// default Middle Center
//End Defaults

var Prefs ={}; //Object to hold preferences.
var prefsFile = File(Folder.temp + "/RotateLayerAboutPreferences.dat");
//If preferences do not exit use defaults
if(!prefsFile.exists){
	alert("Create Preference File");
	Prefs.Cpys  = dfltCpys;
	Prefs.Pos  = dfltPos;
	prefsFile.open('w');
	prefsFile.write(Prefs.toSource());
	prefsFile.close();
	}
else{//Preferences exist so open them
	alert("Read Preference File");
	prefsFile.open('r');
	Prefs = eval(prefsFile.read());
	prefsFile.close();
    }

alert(Prefs.Cpys + " , " + Prefs.Pos);