// USE CASE: Single click field text extraction
public static void Single_click_field_text_extraction(IEngine engine)
{
// We want to implement a feature allowing the user of our application to
// match fields on the page by simply clicking on the text in the image.
trace("Create a sample document...");
IDocument document = PrepareNewRecognizedDocument(engine);
trace("Extract all background text regions on a page...");
IPage page = document.Pages[0];
ITextRegions textRegions = page.ExtractTextRegions();
traceBegin("Create a list of found text regions...");
for (int i = 0; i < textRegions.Count; i++)
{
ITextRegion textRegion = textRegions[i];
string text = textRegion.Text.Text;
IRectangle r = textRegion.Region.BoundingRectangle;
trace(string.Format("'{0}' - [{1},{2},{3},{4}]", text, r.Left, r.Top, r.Right, r.Bottom));
}
traceEnd("");
// Now it is quite simple to implement the desired behavior.
// Suppose the user 'sees' the word 'ENGLAND' and clicks on it.
// In this sample we find the clicked region by text, in a real
// application we would find it as containing the clicked point
ITextRegion clickedRegion = null;
for (int i = 0; i < textRegions.Count; i++)
{
ITextRegion textRegion = textRegions[i];
if (textRegion.Text.Text == "ENGLAND")
{
clickedRegion = textRegion;
break;
}
}
assert(clickedRegion != null);
// In our implementation we can either use the prerecognized text for the region (which is
// fast and usually quite accurate) or set the required field region to enclose the found text
// region and rerecognize the field to apply field-specific recognition parameters:
IField theField = document.Sections[0].Children[2];
assert(theField.Name == "DeliveryAddress");
IBlock theBlock = theField.Blocks[0];
IRegion newRegion = engine.CreateRegion();
IRectangle br = clickedRegion.Region.BoundingRectangle;
newRegion.AddRect(br.Left, br.Top, br.Right, br.Bottom);
theBlock.Region = newRegion;
IBlocksCollection blocksToRerecognize = engine.CreateBlocksCollection();
blocksToRerecognize.Add(theBlock);
document.RecognizeBlocks(blocksToRerecognize);
assert(theField.Value.AsString == "ENGLAND");
}
