Method and apparatus for analyzing computer screens

In a computer system, an automated method for detecting differences between first and second screen images produced by different versions of a computer application, the method comprising the steps of:

• interpreting the first screen image to generate a first set of machine-readable attributes describing visual attributes of the first screen image;
• interpreting the second screen image to generate a second set of machine-readable attributes describing visual attributes of the second screen image;
• and
• automatically processing the first and second sets of machine-readable attributes to provide a comparison between the first and second screen images.

In a computer system, a method for comparing first and second digital images respectively corresponding to first and second outputs of first and second different computer applications, the method comprising the steps of:

• populating a first data structure with a set of machine-readable attributes describing the first digital image by determining related picture elements (pixels) comprising components of the first digital image;
• populating a second data structure with a set of machine-readable attributes describing the second digital image by determining related pixels comprising components of the second digital image;
• and
• analyzing the machine-readable attributes represented in the first and second data structures to automatically generate a comparison of the first and second digital images.

A computer-readable medium having instructions for determining differences between first and second screen images generated by first and second computer applications respectively, the instructions performing the steps of:

• capturing imaging data into a first image file for the first screen image, where the imaging data has been generated by a first computer application for rendering the first screen image from machine-readable source data;
• capturing imaging data into a second image file for the second screen image, where the imaging data has been generated by a second computer application, that is different from the first computer application, for rendering the second screen image from the same machine-readable source data that generated the imaging data for the first screen image;
• automatically comparing the imaging data in the first and second image files;
• and
• generating from the comparison of the image files a data structure containing visual differences between the first and second screen images.