AutoCropper

Overview

This tool will automatically crop an image sequence based on how it differs from a reference image.

This file was originally hosted on the InvisibleThreads website until 2008. It has now been archived. The original layout and formatting for this document is missing from the archives — sorry!

Quick Links

Requirements

This utility was written by Kendall Anderson, with a valuable portion of code by Werner Sharp, posted publicly on the lingo-l discussion list.

User Guide

This document describes how to install and use AutoCropper v1.2 within Macromedia Director 8.0 or greater.

Installing AutoCropper v1.2

  1. Close Director if it is running.
  2. Copy the source file (AutoCropper v1.2.dir) into your Macromedia Director XTRAS folder. For example, on a Windows machine, this might be located in: C:\Program Files\Macromedia\Director 8\Xtras\
  3. Restart Director.

Starting AutoCropper v1.2

  1. The installation step installs AutoCropper v1.2 as a MIAW Xtra. You should now see AutoCropper v1.2 listed in your Xtras menu. To start the program, select: Xtras -> AutoCropper v1.2. AutoCropper should be found under the Xtras menu

Using AutoCropper v1.2

  1. Define the reference image. Select the reference bitmap
  2. Define the images to crop. Select the bitmaps to crop
  3. Choose the cropping method.
  4. Begin the cropping process.

Cropping Modes

There are two cropping modes: normal crop and fast crop. This document will illustrate the differences between them.

Normal Crop   Fast Crop
  • returns all pixels within a rectangular region defining the changing area from the reference image
 
  • returns an image containing only the pixels which have changed from the reference image
Pros & Cons   Pros & Cons
  • PRO: resultant image can be composited on the stage using the fastest ink mode, copy ink
 
  • PRO: resultant image typically is smaller (kb) than Normal Crop because only the differing pixels are contained
  • PRO: cropping process is faster
  • CON: cropping process is slower than Fast Crop
 
  • CON: cannot use copy ink with resultant image

Given a reference image and an image to crop:

reference image
reference image
  image to crop
image to crop

The final cropped image for each cropping type is as follows:

output of Normal Crop method
cropped using Normal Crop method
  output of Fast Crop method
cropped using Fast Crop method

If there are any questions about this document or how to use AutoCropper, please feel free to contact me.


Copyright © 2001 Kendall Anderson | Invisible Threads