KEMBAR78
Automated visual-regression-testing | PPTX
A Visual Comparison
Approach to Automated
Regression Testing
(PDF to PDF Compare)
Regression Testing
• Type of software testing that seeks to uncover new bugs in
existing functional areas of a system after changes have been
made to them
• Ensure that a change has not introduced new faults and that
the intended results are still being produced
VisualRegressionTesting
2
Visual Regression Testing
• Compares visual output
• New file = or ≠ reference file
• Different underlying code can produce the same output
• Testing is necessary to see if anything changed
• Produce wanted results
• Produce unwanted results
• Break something that was working fine before
• Involves testing either
• A subset of documents
• A large collection of documents (preferred)
VisualRegressionTesting
3
The Antenna House Problem
• The need to regression test new releases of Antenna House
Formatter
• At least 8 maintenance releases a year
• Regression Testing (Visual Method)
• Has been done manually by visually comparing output of old and
new files
• Time consuming
• Prone to missing minor (but important) differences
• Can lead to delays in product releases
• Done only on candidate release versions
• Increase in support calls due to missed errors
VisualRegressionTesting
4
Going Automated Challenges
•Compare outputs visually, not the
underlying code
•High speed performance
•Support for large collection of
documents
•Method to generate meaningful
reports
VisualRegressionTesting
5
What is AHRTS?
• Java application
• Automated visual comparison tool
• Precision pixel-by-pixel comparison of output documents
• Scalable & fast regression testing
• Regression testing of new releases of AH Formatter
• An automated system for comparing versions of
rendering software or rendered output
• Beyond regression testing
• Pre-production system check
• Stylesheet development
• Installation validation
• System(s) certification
VisualRegressionTesting
6
Homogenize
Properties
Compare
Homogenize
Properties
Is the content
the same?
PDF2PDF
Select PDF
documents
to be
compared
PDF 1 PDF 2
Extract PDF
code as
character
strings
Extract PDF
code as
character
strings
Return XML
Report Page
No
Difference
Yes
How does it work?
VisualRegressionTesting
7
Are pages
the same?
PDF 1 PDF 2
Compare
Pixel by Pixel
Page by
Page
Convert
to Bitmap
Convert
to Bitmap
Return XML
Report Page
Difference
No
Create
Composite
Image of
Differences
No
Return XML
Report Page
No Difference
Yes
Format to PDF
using
XSL-FO
How does it work?
VisualRegressionTesting
8
Benefits
• Automates regression testing
• High speed performance
• 90%+ reduction in human effort
• Handles large document comparisons
• Significantly more accurate and reliable
• Able to catch more subtle differences
• Able to test more often, fewer problems results
in overall better product
• Fewer support issues
VisualRegressionTesting
9
Conclusion
Beyond regression testing, a PDF to PDF
comparison tool like Antenna House
Regression Testing System, can have a
significant impact on improving software as
it may play many roles in the development
cycle for any system generating visual
outputs.
VisualRegressionTesting
10
Thank you!
For more information:
www.antennahouse.com
celina@antennahouse.com

Automated visual-regression-testing

  • 1.
    A Visual Comparison Approachto Automated Regression Testing (PDF to PDF Compare)
  • 2.
    Regression Testing • Typeof software testing that seeks to uncover new bugs in existing functional areas of a system after changes have been made to them • Ensure that a change has not introduced new faults and that the intended results are still being produced VisualRegressionTesting 2
  • 3.
    Visual Regression Testing •Compares visual output • New file = or ≠ reference file • Different underlying code can produce the same output • Testing is necessary to see if anything changed • Produce wanted results • Produce unwanted results • Break something that was working fine before • Involves testing either • A subset of documents • A large collection of documents (preferred) VisualRegressionTesting 3
  • 4.
    The Antenna HouseProblem • The need to regression test new releases of Antenna House Formatter • At least 8 maintenance releases a year • Regression Testing (Visual Method) • Has been done manually by visually comparing output of old and new files • Time consuming • Prone to missing minor (but important) differences • Can lead to delays in product releases • Done only on candidate release versions • Increase in support calls due to missed errors VisualRegressionTesting 4
  • 5.
    Going Automated Challenges •Compareoutputs visually, not the underlying code •High speed performance •Support for large collection of documents •Method to generate meaningful reports VisualRegressionTesting 5
  • 6.
    What is AHRTS? •Java application • Automated visual comparison tool • Precision pixel-by-pixel comparison of output documents • Scalable & fast regression testing • Regression testing of new releases of AH Formatter • An automated system for comparing versions of rendering software or rendered output • Beyond regression testing • Pre-production system check • Stylesheet development • Installation validation • System(s) certification VisualRegressionTesting 6
  • 7.
    Homogenize Properties Compare Homogenize Properties Is the content thesame? PDF2PDF Select PDF documents to be compared PDF 1 PDF 2 Extract PDF code as character strings Extract PDF code as character strings Return XML Report Page No Difference Yes How does it work? VisualRegressionTesting 7
  • 8.
    Are pages the same? PDF1 PDF 2 Compare Pixel by Pixel Page by Page Convert to Bitmap Convert to Bitmap Return XML Report Page Difference No Create Composite Image of Differences No Return XML Report Page No Difference Yes Format to PDF using XSL-FO How does it work? VisualRegressionTesting 8
  • 9.
    Benefits • Automates regressiontesting • High speed performance • 90%+ reduction in human effort • Handles large document comparisons • Significantly more accurate and reliable • Able to catch more subtle differences • Able to test more often, fewer problems results in overall better product • Fewer support issues VisualRegressionTesting 9
  • 10.
    Conclusion Beyond regression testing,a PDF to PDF comparison tool like Antenna House Regression Testing System, can have a significant impact on improving software as it may play many roles in the development cycle for any system generating visual outputs. VisualRegressionTesting 10
  • 11.
    Thank you! For moreinformation: www.antennahouse.com celina@antennahouse.com

Editor's Notes

  • #7 While it was originally designed to be used for AH Formatter, we have found that it can test a PDF of any source, any rendering software, and we have been using to test other PDF products that we provide.