GetHistogram method (ILEADRasterProcess)

Visual Basic example

Visual C++ 5.0 example

Delphi 4 example

C++ Builder example

 

Syntax

short GetHistogram (ILEADRaster *pRaster, long lFlags);

Overview

Refer to Using Histograms.

Remarks

Updates the array that charts how many times each intensity level occurs in the bitmap. This method can chart red, green, and blue separately or together.

You can access the array values using the HistogramTable property. Intensity levels range from 0 to 255. Therefore, the resulting array has 256 items, indexed by intensity value. The value of each item is the number of occurrences of the intensity level.

This method supports 12 and 16-bit grayscale images and 48 and 64-bit color images. Support for 12 and 16-bit grayscale images and 48 and 64-bit color images is available only in the Document/Medical toolkits.

For 48 and 64-bit images, the intensity levels range from 0 to 65535. Therefore, the resulting array has 65536 items, indexed by intensity value. The value of each item is the number of occurrences of the intensity level.

Specifically, the HistogramTable property holds at least 2^(HighBit – LowBit + 1) entries if HIST_LOWHIGH_BITS is set in lFlags. If HIST_ALL_BITS is set in lFlags, the table must hold at least 4096 for 12-bit bitmaps and 65536 for 16-bit bitmaps.

This method supports signed data images.

See Also

Topics:

Raster Images: Using Histograms

 

Raster Images: Where the Region Preempts the Bitmap

 

Changing Brightness and Contrast