In v2015R1, Qoppa added an optional module to our PDF editing and annotating component jPDFEditor that allows to compare 2 PDF documents or drawings by by overlaying / superimposing them.
Compare Overlay allows to superimpose 2 drawings or documents and immediately identify the differences using color coding:
- Elements present only in first drawing appear in red (customizable color).
- Elements present only in second drawing appear in green (customizable color).
- Alignment tools allow moving and resizing second document dynamically for perfect match.
- Option to export the overlay comparison as a new PDF, with the 2 drawings included as layers.
At any time during the comparison, using the toolbar, annotate or markup onto the main document (Document A). - Switch over to the Side by Side Comparison mode by clicking on the “Side by Side” button in the Overlay Comparison dialog.
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Comparison Adjustment Options
The following adjustment options are available:
- View – choose to display both or each document individually
- Color – select the color of each document (the default colors generally provide the best results). Read our KB entry regarding Choosing colors for overlay PDF comparison.
- X & Y – adjust the X & Y values of Document B to move it left, right, up, or down
- Rotate – adjust the rotation of Document B if needed
- Scale – make Document B smaller or larger if needed
Exporting Comparison as a PDF
The comparison can be exported as a single document with the overlay as the base layer and Documents A & B as layers within the document. To export, click on the “Export” button in the “Compare Overlay” dialog.
- The overlay comparison view will be rasterized (turned into an image per page) as the base layer.
- The original Document A – Layer 1
- The original Document B – Layer 2
Exiting Comparison Mode
To exit the comparison mode, just click on the “Close” button on the Overlay Compare dialog to return back to Document A.
Contact info@qoppa.com if you’re interested in licensing this new module.