GetText Method (original) (raw)
Summary
Gets the recognition OCR data for a zone in this IOcrPage as a string.
Syntax
C#
Objective-C
C++/CLI
Java
Python
- (nullable NSString *)textForZoneAtIndex:(NSInteger)index error:(NSError **)error NS_SWIFT_NAME(zoneText(at:)); Parameters
zoneIndex
0-based index of the zone. Pass -1 for this parameter to get the text for all page zones at once.
Return Value
A String containing the recognized characters found (or an empty string if zones on the page contains no recognition data).
Example
This example gets the values of particular fields from a document.
using Leadtools;
using Leadtools.Codecs;
using Leadtools.Ocr;
using Leadtools.Forms.Common;
using Leadtools.WinForms;
using Leadtools.Drawing;
public void RecognizeTextExample()
{
// Get the form file name
Console.WriteLine("Setting up the form...");
string formFileName = GetMyForm();
// Assume we get the field information from an external source such as a database or an XML file
string[] fieldNames =
{
"Name",
"Address",
"SSN"
};
LeadRect[] fieldBounds =
{
new LeadRect(800, 160, 1500, 220),
new LeadRect(800, 560, 1500, 220),
new LeadRect(800, 960, 1500, 220)
};
int fieldCount = fieldNames.Length;
string[] fieldValues = new string[fieldCount];
// Create an instance of the engine
using (IOcrEngine ocrEngine = OcrEngineManager.CreateEngine(OcrEngineType.LEAD))
{
// Start the engine using default parameters
Console.WriteLine("Starting up the engine...");
ocrEngine.Startup(null, null, null, LEAD_VARS.OcrLEADRuntimeDir);
// Create a page from the image file
Console.WriteLine("Creating a page...");
using (IOcrPage ocrPage = ocrEngine.CreatePage(ocrEngine.RasterCodecsInstance.Load(formFileName, 1), OcrImageSharingMode.AutoDispose))
{
// Get our fields
for (int i = 0; i < fieldCount; i++)
{
// Clear all the zones in the page
ocrPage.Zones.Clear();
// Add our field zone
OcrZone ocrZone = new OcrZone();
ocrZone.ZoneType = OcrZoneType.Text;
ocrZone.Bounds = fieldBounds[i];
ocrZone.Name = fieldNames[i]; // Optional
Console.WriteLine("Adding the zone for field {0} to the page...", ocrZone.Name);
ocrPage.Zones.Add(ocrZone);
// Recognize the page. This will only recognize the zone we added
Console.WriteLine("Recognizing the page...");
ocrPage.Recognize(null);
fieldValues[i] = ocrPage.GetText(0);
}
}
// Shutdown the engine
// Note: calling Dispose will also automatically shutdown the engine if it has been started
Console.WriteLine("Shutting down...");
ocrEngine.Shutdown();
}
// We are done, show the fields
Console.WriteLine("-------------------------------------");
Console.WriteLine("Done, values extracted from the form:");
Console.WriteLine("-------------------------------------");
for (int i = 0; i < fieldCount; i++)
Console.WriteLine("{0} : {1}", fieldNames[i], fieldValues[i]);
}
private string GetMyForm()
{
string formFileName = LEAD_VARS.ImagesDir + "MyForm.tif";
// In this example we will create the form every time
// This will be a TIF file 11 by 8.5 inches in size containing a name, address and social security fields
using (RasterImage image = new RasterImage(
RasterMemoryFlags.Conventional,
2544,
3294,
24,
RasterByteOrder.Bgr,
RasterViewPerspective.BottomLeft,
null,
IntPtr.Zero,
0))
{
image.XResolution = 300;
image.YResolution = 300;
// Draw our fields into this image
IntPtr hdc = RasterImagePainter.CreateLeadDC(image);
try
{
using (Graphics g = Graphics.FromHdc(hdc))
{
g.FillRectangle(Brushes.White, 0, 0, image.ImageWidth - 1, image.ImageHeight - 1);
using (Font f = new Font("Times New Roman", 80, FontStyle.Regular))
{
using (Pen p = new Pen(Color.Black, 4))
{
using (StringFormat sf = new StringFormat())
{
sf.LineAlignment = StringAlignment.Center;
// Draw the fields
// Name
g.DrawString("Name:", f, Brushes.Black, 200, 200);
Rectangle rc = new Rectangle(800, 160, 1500, 220);
g.DrawRectangle(p, rc);
string value = "John Doe";
g.DrawString(value, f, Brushes.Black, rc, sf);
// Address
g.DrawString("Address:", f, Brushes.Black, 200, 600);
rc = new Rectangle(800, 560, 1500, 220);
g.DrawRectangle(p, rc);
value = "1234 Main Street, USA";
g.DrawString(value, f, Brushes.Black, rc, sf);
// Social security number
g.DrawString("SSN:", f, Brushes.Black, 200, 1000);
rc = new Rectangle(800, 960, 1500, 220);
g.DrawRectangle(p, rc);
value = "123-45-6789";
g.DrawString(value, f, Brushes.Black, rc, sf);
}
}
}
}
}
finally
{
RasterImagePainter.DeleteLeadDC(hdc);
}
// Save this image to disk
using (RasterCodecs codecs = new RasterCodecs())
{
codecs.Save(image, formFileName, RasterImageFormat.CcittGroup4, 1);
}
}
return formFileName;
}
static class LEAD_VARS
{
public const string ImagesDir = @"C:\LEADTOOLS22\Resources\Images";
public const string OcrLEADRuntimeDir = @"C:\LEADTOOLS22\Bin\Common\OcrLEADRuntime";
}