PanoramaImageSplit.js for scriptable.app

PanoramaImageSplit.js

// Variables used by Scriptable.
// These must be at the very top of the file. Do not edit.
// icon-color: gray; icon-glyph: vector-square;



// script     : PanoramaImageSplit.js
// version    : 1.0.0 
// description: Splits Panorama Images into multiple for InstaStories
// author     : @wolfposd
// date       : 2022-03-17


let image = await Photos.fromLibrary();

let splitDimensions = calculateSplits(image);

if(splitDimensions)
  performSplits(image, splitDimensions)

Script.complete();


function calculateSplits(img) {
  const ratio = 0.5625; 
  // ratio based on instagram story 1080 x 1920 = 0.5625

  let w = img.size.width; 
  let h = img.size.height;
  console.log(w + " x " + h);  
  
  if(h > w) {
    showAlert("Dimension error", "Image width is smaller than height");
    return;
  }
  let desiredWidth = h * ratio; 
  let divisions = w / desiredWidth;
  //console.log("desiredWidth " + desiredWidth);
  //console.log(w / desiredWidth); 
  //console.log("divisions " + divisions);
  
  let offset = 0.25 * Math.abs(desiredWidth - (w / Math.floor(divisions)) ); 
  //console.log("offset: " + offset);

  let result = [];

  for(var i = 0 ; i < divisions; i++) {
    let s;
    if( i == 0) {
      s = {"start" : 0, "end" : Math.floor(desiredWidth)};
    }
    else {
      let start = (i * desiredWidth) - offset;
      s = {"start" : Math.floor(start),  "end" : Math.floor(start + desiredWidth)};
    }

    result.push(s);
  }

  return result;
}

function performSplits(image, splitDimensions) {
  console.log("Starting splits " + splitDimensions.size);
 
  const targetHeight = image.size.height;
  const imageWidth = image.size.width;

  for(var split of splitDimensions) {
    let ctx = new DrawContext();

    let targetWidth = split.end - split.start;
    ctx.size = new Size(targetWidth, targetHeight);
    
    let rect = new Rect(-1 * split.start, 0, imageWidth, targetHeight );
 
    //console.log("Rect:" + JSON.stringify(rect));
    ctx.drawImageInRect(image, rect);

    let splitImage = ctx.getImage(); 
    Photos.save(splitImage);
  }

  showAlert("Done", "Created " + splitDimensions.length + " photos");
}


function showAlert(title, text) {
  let alert = new Alert();
  alert.title = title;
  alert.message = text;
  alert.present();
}