Applies binary segmentation to a bitmap by filtering the specified bitmap to detect colors in a specified intensity range, in the specified color channel(s).
#include "l_bitmap.h"
L_LTIMGCLR_API L_INT L_IntensityDetectBitmap(pBitmap, uLow, uHigh, crInColor, crOutColor, uChannel, uFlags)
Pointer to the bitmap handle referencing the bitmap.
Lowest intensity to detect. Possible values range from 0 - 65535 for 64-bit, 48-bit and 16-bit grayscale images and from 0 - 4095 for 12-bit grayscale images. Otherwise, it is from 0 to 255.
Highest intensity to detect. Possible values range from 0 - 65535 for 64-bit, 48-bit and 16-bit grayscale images and from 0 - 4095 for 12-bit grayscale images. Otherwise, it is from 0 to 255.
The color used to fill those pixels having an intensity value between uLow
and uHigh
. This parameter has no effect if the uChannel
parameter is set to IDB_CHANNEL_MASTER. If for example the uChannel parameter is set to IDB_CHANNEL_RED, then the red component of crInColor will be used to fill the pixels having a red component value between uLow and uHigh.
The color used to fill those pixels having an intensity value less than uLow
or greater than uHigh
. This parameter has no effect if the uChannel
parameter is IDB_CHANNEL_MASTER. If for example the uChannel parameter is set to IDB_CHANNEL_RED, then the red component of crOutColor will be used to fill the pixels having a red component value less than uLow or greater than uHigh.
A value that indicates the channel to process. Possible values are:
Value | Meaning |
---|---|
IDB_CHANNEL_MASTER * | [0x0000] Grayscale Channel. |
IDB_CHANNEL_RED | [0x0001] Red Channel. |
IDB_CHANNEL_GREEN | [0x0010] Green Channel. |
IDB_CHANNEL_BLUE | [0x0100] Blue Channel. |
Reserved for future use. Must be 0.
Value | Meaning |
---|---|
SUCCESS | The function was successful. |
< 1 | An error occurred. Refer to Return Codes. |
This function is useful for pre-processing images to improve barcode recognition results.
The image is divided into two parts: inner and outer, corresponding to the values of uLow
and uHigh
.
Process 2 or more channels at a time by OR-ing two or more flags.
To obtain the same result as the old L_IntensityDetectBitmap(pBitmap, uLow, uHigh) of version 13 and earlier, pass the following parameters:
L_IntensityDetectBitmap(pBitmap, uLow, uHigh, RGB(0, 0, 0), RGB(255, 255, 255), CHANNEL_RED | CHANNEL_GREEN | CHANNEL_BLUE);
This function also supports 12- and 16-bit grayscale and 48- and 64-bit color images. Support for 12- and 16-bit grayscale and 48- and 64-bit color images is available in the Document and Medical Imaging toolkits.
This function does not support 32-bit grayscale images. It returns the error code ERROR_GRAY32_UNSUPPORTED if a 32-bit grayscale image is passed to this function.
To update a status bar or detect a user interrupt during execution of this function, refer to L_SetStatusCallback.
In order to speed up widely used image processing filters in LEADTOOLS, the grayscale value (master channel) of a colored image is calculated using the following formulas:
#define CalcGrayValue(r, g, b) ((L_UCHAR)(((L_UCHAR) (((2 * (L_UINT) (r)) + (5 * (L_UINT) (g)) + (L_UINT) (b) + 4) / 8))))
#define CalcGrayValue16(r, g, b) ((L_UINT16) (((2 * (L_UINT32) (r)) + (5 * (L_UINT32) (g)) + (L_UINT32) (b) + 4) / 8))
#define CalcGrayValue32(r, g, b) ((L_UINT32) (((2 * (L_UINT32) (r)) + (5 * (L_UINT32) (g)) + (L_UINT32) (b) + 4) / 8))
Intensity Detect Function - Before
Intensity Detect Function - After
View additional platform support for this Intensity Detect function.
Win32, x64, Linux.
This example loads a bitmap and applies the filter on it.
L_INT IntensityDetectBitmapExample(L_VOID)
{
L_INT nRet;
BITMAPHANDLE LeadBitmap; /* Bitmap handle to hold the loaded image. */
/* Load the bitmap, keeping the bits per pixel of the file */
nRet = L_LoadBitmap(MAKE_IMAGE_PATH(TEXT("redeye.cmp")), &LeadBitmap, sizeof(BITMAPHANDLE), 0, ORDER_BGR, NULL, NULL);
if (nRet != SUCCESS)
return nRet;
/* Apply the filter*/
nRet = L_IntensityDetectBitmap(&LeadBitmap, 128, 255, RGB(0, 0, 0), RGB(255, 255, 255), IDB_CHANNEL_MASTER, 0);
if (nRet != SUCCESS)
return nRet;
nRet = L_SaveBitmap(MAKE_IMAGE_PATH(TEXT("Result.BMP")), &LeadBitmap, FILE_BMP, 24, 0, NULL);
if (nRet != SUCCESS)
return nRet;
//free bitmap
if (LeadBitmap.Flags.Allocated)
L_FreeBitmap(&LeadBitmap);
return SUCCESS;
}
Help Collections
Raster .NET | C API | C++ Class Library | HTML5 JavaScript
Document .NET | C API | C++ Class Library | HTML5 JavaScript
Medical .NET | C API | C++ Class Library | HTML5 JavaScript
Medical Web Viewer .NET
Multimedia
Direct Show .NET | C API | Filters
Media Foundation .NET | C API | Transforms
Supported Platforms
.NET, Java, Android, and iOS/macOS Assemblies
Imaging, Medical, and Document
C API/C++ Class Libraries
Imaging, Medical, and Document
HTML5 JavaScript Libraries
Imaging, Medical, and Document
Your email has been sent to support! Someone should be in touch! If your matter is urgent please come back into chat.
Chat Hours:
Monday - Friday, 8:30am to 6pm ET
Thank you for your feedback!
Please fill out the form again to start a new chat.
All agents are currently offline.
Chat Hours:
Monday - Friday
8:30AM - 6PM EST
To contact us please fill out this form and we will contact you via email.