mediaLib Library Functions mlib_ImageHistogram2(3MLIB)
NAME
mlib_ImageHistogram2 - histogram
SYNOPSIS
cc [ flag... ] file... -lmlib [ library... ]
#include
mlib_status mlib_ImageHistogram2(mlib_s32 **histo, const mlib_image *img,
const mlib_s32 *numBins, const mlib_s32 *lowValue,
const mlib_s32 *highValue, mlib_s32 xStart, mlib_s32 yStart,
mlib_s32 xPeriod, mlib_s32 yPeriod);
DESCRIPTION
The mlib_ImageHistogram2() function creates a histogram by
scanning an image, counting the number of pixels within agiven range for each channel of the image, and then generat-
ing a histogram. The image can have 1, 2, 3 or 4 channels. The data type ofthe image can be MLIB_BYTE, MLIB_SHORT, MLIB_USHORT, or
MLIB_INT. The histogram must have the same number of chan-
nels as the image has. One entry of the histogram, or a bin, is used to accumulatethe number of pixels within a certain sub-range. The legal
pixel range and the number of bins may be controlled separately.If binWidth is defined as (highValue - lowValue )/numBins
then bin i counts pixel values in the following range: lowValue + i*binWidth < x < lowValue + (i + 1)*binWidth The set of pixels scanned may furthermore be reduced by specifying xPeriod and yPeriod parameters that specify the sampling rate along each axis. The set of pixels to be accumulated may be obtained from the following equation:x = xStart + p*xPeriod; 0 < p < (w - xStart)/xPeriod
y = yStart + q*yPeriod; 0 < q < (h - yStart)/yPeriod
SunOS 5.11 Last change: 2 Mar 2007 1
mediaLib Library Functions mlib_ImageHistogram2(3MLIB)
It is the user's responsibility to clear the histogram tablebefore this function is called and to ensure that the histo-
gram table supplied is suitable for the source image and theparameters. Otherwise, the result of this function is unde-
fined.The range from lowValue[k] to (highValue[k] - 1) must be a
valid subrange of the image type range.PARAMETERS
The function takes the following arguments:histo Pointer to histogram. The format of the histo-
gram is histo[channel][index]. The index valuesfor channel i can be 0, 1, ..., numBins[i]-1.
img Pointer to source image. numBins The number of bins for each channel of the image.lowValue The lowest pixel value checked for each chan-
nel.highValue The highest pixel value checked for each chan-
nel. When counting the pixel values, highValue is not included. xStart The initial X sample coordinate. yStart The initial Y sample coordinate. xPeriod The X sampling rate. xPeriod > 1. yPeriod The Y sampling rate. yPeriod > 1.RETURN VALUES
The function returns MLIB_SUCCESS if successful. Otherwise
it returns MLIB_FAILURE.
ATTRIBUTES
SunOS 5.11 Last change: 2 Mar 2007 2
mediaLib Library Functions mlib_ImageHistogram2(3MLIB)
See attributes(5) for descriptions of the following attri-
butes:____________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|_____________________________|_____________________________|
| Interface Stability | Committed ||_____________________________|_____________________________|
| MT-Level | MT-Safe |
|_____________________________|_____________________________|
SEE ALSO
mlib_ImageHistogram(3MLIB), attributes(5)
SunOS 5.11 Last change: 2 Mar 2007 3