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Deskew Library (royalties free)

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This deskew sdk (API) allows the automatic skew detection and correction in scanned or faxed images. The skew is the inevitable slope present in the images acquired by scanners using an ADF (automatic document feeder) or received by fax. Straightening the images is a very important pre-processing step for improving the compression rate, the visualization aspect, the line-removal and the accuracy using ICR/OCR

Prima dell'applicazione della libreria DESKEW   Dopo l'applicazione della libreria DESKEW 
While other libraries usually allow users to deskew only monochrome images, Recogniform library allows you to deskew both grayscale and color images!

Using interpolation in skew correction, the aliasing due to the rotation is minimized and really perfect images are obtained (as rotating the paper!).

You can perform the deskew (skew detection and correction) in one-step, or in two distinct steps.

You can set the following parameters:

  • Max Angle: system will try to detect and correct skew only from -MaxAngle to +MaxAngle.
  • Resolution: the smallest skew to detect. It is Usually  0.1, but if you need fast processing you can increase this value.
  • Speed and accuracy: the value for  balancing speed/accuracy ratio.
  • Background Color: the color of the new background after the rotation
  • Interpolation: this option performs interpolation to obtain a better result and to avoid  aliasing

You have to supply the DIB (Device Independent Bitmap) in input to the process.

The deskew procedure is fast and accurate.

For testing this library you can download a demo application (400 KB) that allows you to use this function with your TIF images: please give us your feedback and your comments after the test !

Here is source code in Microsoft Visual C++ of a sample application using the deskew library:

#include "stdafx.h"
#include "stdio.h"
#include "recodeskew.c"

int APIENTRY WinMain(HINSTANCE hInstance,
                     HINSTANCE hPrevInstance,
                     LPSTR     lpCmdLine,
                     int       nCmdShow)

 // Load dynamically the library

 // Init the DESKEW session
 int Session= DESKEW_Init("demo", "demo");

 long hBitmap;

 // Check if a DIB is available in clipboard
 bool bAvail= IsClipboardFormatAvailable(CF_DIB);

 hBitmap = 0;

 if (bAvail)
   // Open the Clipboard
   // Retrieve the DIB from clipboard 
   hBitmap = (long) GetClipboardData(CF_DIB);

   // Detect and correct skew on the DIB
   double SkewAngle= DESKEW_DetectAndCorrect(Session, (long) hBitmap);


   // Set the deskewed DIB to clipboard
   SetClipboardData(CF_DIB, (void*)hBitmap);

   // Close the Clipboard	

   char  buffer[200];

   // Format the output message
   if (SkewAngle!=0)

    sprintf( buffer, "Image deskewed by %f degree !
      You can paste in your application...", SkewAngle);


    sprintf( buffer, "Image don't need to be deskewd !");

   // Show the result
  MessageBox(NULL, buffer, "RESULT", MB_OK);
 // Show an error message
 else MessageBox(NULL, "Unable to paste DIB", "ERROR", MB_OK);

 // Close the session

 // Unload the library	

 return 0;

Price and orders
The price of this library is 599 EUR. The library is royalties free so, till 1000 runtimes, it can be distributed with any end-user application without paying licenses fee: if you need distribute a larger number of runtimes you have to buy further licenses of the product. You can order on-line in our e-commerce store or using our contacts page.

Evaluation Version
You can download an evaluation version of this product for Visual Basic, Visual C++ or Delphi.

More Info
For more info about this product please use the
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