Background Form Image Considerations

Because ScanTools is a dropout ink system, attempting to perform OMR editing on a raw clip would simply show marked OMR response positions with no surrounding context information. Therefore, ScanTools supports a background form image, which is merged with the clips during editing and image archiving, resulting in clips positioned over a picture of the form.

ScanTools does not generate these background form TIFF files. Best results will be obtained if the TIFF is generated by the same software that was used to design the form, guaranteeing dimensional accuracy. The resolution of the TIFF should be the minimum required for a clear, usable image in the editor at the desired zoom factor - larger TIFFs will take more time to load and may cause noticeable delays during editing. The TIFF can, and probably should, be in color. For best performance, the TIFF should be a 16-color image.

There are no minimum requirements for the size or quality of the background form TIFF but it must be accurate dimensionally for clips to be superimposed on it. Good results are obtained with 150 dpi to 400 dpi resolution, 16-color TIFFs, with 400 dpi background form images providing the best image quality. Additionally, for best results, the background form files supplied by the vendor should be in the same orientation as the way the form is scanned.

Specifying Background Form Files for Your Application: Background form image files are specified for your application in the Add/Replace Background Form Images for Sheet # dialog.

Background Form File Name and Path Name Reference: The background form image file and path names for your application are identified in the Image Clips dialog.

Improving Background Form Alignment: If your form has the required form ID mark and timing marks, you can use the OMR/Merge Horizontal Adjustment in the Application Settings dialog to improve the alignment of the background form image to the scanned image. See Also: Horizontal Adjustment.

NOTE: If you install your application by using the Install Application function, and a background form image file is identified for the application on the Image Clips dialog, then ScanTools will search the directory path specified for it during installation of the application. If it does not find the directory, it will search the ScanTools Plus\Applications directory for the specified file. If it is found in the ScanTools Plus directory, the directory path will be updated to reflect that path. If it is not found, ScanTools Plus will return the error "A background form image cannot be loaded."