mlib_ImageHistogram2(3MLIBmediaLib Library Functionmlib_ImageHistogram2(3MLIB)NAMEmlib_ImageHistogram2 - histogram
SYNOPSIS
cc [ flag... ] file... -lmlib [ library... ]
#include <mlib.h>
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 a given range for each
channel of the image, and then generating a histogram.
The image can have 1, 2, 3 or 4 channels. The data type of the image
can be MLIB_BYTE, MLIB_SHORT, MLIB_USHORT, or MLIB_INT. The histogram
must have the same number of channels as the image has.
One entry of the histogram, or a bin, is used to accumulate the 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 xPe‐
riod 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
It is the user's responsibility to clear the histogram table before
this function is called and to ensure that the histogram table supplied
is suitable for the source image and the parameters. Otherwise, the
result of this function is undefined.
The range from lowValue[k] to (highValue[k] - 1) must be a valid sub‐
range of the image type range.
PARAMETERS
The function takes the following arguments:
histo Pointer to histogram. The format of the histogram is
histo[channel][index]. The index values for 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 channel.
highValue The highest pixel value checked for each channel. 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
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│Interface Stability │Committed │
├─────────────────────────────┼─────────────────────────────┤
│MT-Level │MT-Safe │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOmlib_ImageHistogram(3MLIB), attributes(5)SunOS 5.10 2 Mar 2007 mlib_ImageHistogram2(3MLIB)
