mlib_ImageLookUp(3MLIB) mediaLib Library Functions mlib_ImageLookUp(3MLIB)NAMEmlib_ImageLookUp - table lookup
SYNOPSIS
cc [ flag... ] file... -lmlib [ library... ]
#include <mlib.h>
mlib_status mlib_ImageLookUp(mlib_image *dst, const mlib_image *src,
const void **table);
DESCRIPTION
The mlib_ImageLookUp() function maps the source image to the destina‐
tion image by using the user-specified lookup table.
The source and destination images must have the same width and height.
The source image can be a single channel image or can have the same
number of channels as the destination image. One of the following equa‐
tions is used accordingly:
dst[x][y][i] = table[i][src[x][y][0]]
dst[x][y][i] = table[i][src[x][y][i]]
The source and destination images can have different data types. See
the following table for available variations of the table lookup func‐
tion on image types:
Type [*] BYTE SHORT USHORT INT FLOAT DOUBLE
────────────────────────────────────────────────────────────────────────────────────────
MLIB_BIT Y
MLIB_BYTE Y Y Y Y Y Y
────────────────────────────────────────────────────────────────────────────────────────
MLIB_SHORT Y Y Y Y Y Y
────────────────────────────────────────────────────────────────────────────────────────
MLIB_USHORT Y Y Y Y Y Y
────────────────────────────────────────────────────────────────────────────────────────
MLIB_INT Y Y Y Y Y Y
[*] Each row represents a source data type. Each column represents a
destination data type.
PARAMETERS
The function takes the following arguments:
dst Pointer to destination image.
src Pointer to source image.
table Pointer to lookup table. The data type of the lookup table is
the same as the destination image. The number of entries in
the lookup table is determined by the type of the input image.
The format of the lookup table is:
table[channel][index]
The MLIB_BIT type entries are indexed from 0 to 1. The
MLIB_BYTE type entries are indexed from 0 to 255. The
MLIB_SHORT type entries are indexed from -32768 to -1, then
from 0 to 32767. The MLIB_USHORT type entries are indexed from
0 to 65535. The MLIB_INT type entries are indexed from
-2147483648 to -1, and then from 0 to 2147483647.
If a table covering the full range of input data type is not
available or not realistic, which is mostly true for doing ta‐
ble lookup with an MLIB_INT input image, a smaller table can
be used. In this case, the pointer to the table has to be
adjusted as if it is pointing to the element for the smallest
value of the input data type. For example, to use a table
covering input data range of [-65536, 65535], the pointer
needs to be adjusted as follows:
table_16_32[0] += MLIB_S32_MIN + 65536;
This might cause a pointer arithmetic overflow in 32-bit mode,
but probably works if the overflow is handled as a wrap-
around. If possible, function mlib_ImageLookUp2() should be
used instead.
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_ImageLookUp_Inp(3MLIB), mlib_ImageLookUp2(3MLIB),
mlib_ImageLookUpMask(3MLIB), attributes(5)SunOS 5.10 12 Sep 2007 mlib_ImageLookUp(3MLIB)
