Photoshop动作来填充图像以达到一定的比例

#target photoshop

main ();

function main ()
{
    if (app.documents.length < 1)
    {
        alert ("No document open to resize.");
        return;
    }

    // These can be changed to create images with different aspect ratios.
    var arHeight = 4;
    var arWidth = 5;

    // Apply the resize to Photoshop's active (selected) document.
    var doc = app.activeDocument;

    // Get the image size in pixels.
    var pixelWidth = new UnitValue (doc.width, doc.width.type);
    var pixelHeight = new UnitValue (doc.height, doc.height.type);
    pixelWidth.convert ('px');
    pixelHeight.convert ('px');

    // Determine the target aspect ratio and the current aspect ratio of the image.
    var targetAr = arWidth / arHeight;
    var sourceAr = pixelWidth / pixelHeight;

    // Start by setting the current dimensions.
    var resizedWidth = pixelWidth;
    var resizedHeight = pixelHeight;

    // The source image aspect ratio determines which dimension, if any, needs to be changed.
    if (sourceAr < targetAr)
        resizedWidth = (arWidth * pixelHeight) / arHeight;
    else
        resizedHeight = (arHeight * pixelWidth) / arWidth;

    // Apply the change to the image.
    doc.resizeCanvas (resizedWidth, resizedHeight, AnchorPosition.MIDDLECENTER);
}

 ...
 var pixelWidth = new UnitValue (doc.width, doc.width.type);
 pixelWidth.baseUnit = UnitValue (doc.width.baseUnit, "in");
 var pixelHeight = new UnitValue (doc.height, doc.height.type);
 pixelHeight.baseUnit = UnitValue (doc.height.baseUnit, "in");
 ...