After Effect: create a composition per footage and postprocess it using Mettle Skybox Blur

blur_panoramas.jsx

/**
 * @file Creates a composition for every panorama and adds 360 blur.
 */

var renderQueue = app.project.renderQueue;

var footages = new Array();
for (i = 1; i <= app.project.numItems; i++){
	var item = app.project.item(i);
	if ((item instanceof FootageItem) && (item.mainSource instanceof FileSource) && (item.mainSource.isStill)){
		footages.push(item.id);
	}
}

var l = footages.length;
for (var i = 0; i < l; i++){
	var footage = app.project.itemByID(footages[i]);
	var comp = app.project.items.addComp("panorama-" + i, footage.width, footage.height, 1, 1, 1);
	var layer = comp.layers.add(footage);
	var effect = layer("Effects").addProperty("Skybox Blur");
	effect.Blurriness.setValue(175);

	var queueItem = renderQueue.items.add(comp);
	queueItem.outputModule(1).applyTemplate("PNG Sequence");
	queueItem.outputModule(1).file = new File("Output/panorama-" + i + "-[#].png");
}

renderQueue.render();