Leptonica  1.77.0
Image processing and image analysis suite
Functions
arrayaccess.c File Reference
#include "allheaders.h"

Go to the source code of this file.

Functions

l_int32 l_getDataBit (void *line, l_int32 n)
 
void l_setDataBit (void *line, l_int32 n)
 
void l_clearDataBit (void *line, l_int32 n)
 
void l_setDataBitVal (void *line, l_int32 n, l_int32 val)
 
l_int32 l_getDataDibit (void *line, l_int32 n)
 
void l_setDataDibit (void *line, l_int32 n, l_int32 val)
 
void l_clearDataDibit (void *line, l_int32 n)
 
l_int32 l_getDataQbit (void *line, l_int32 n)
 
void l_setDataQbit (void *line, l_int32 n, l_int32 val)
 
void l_clearDataQbit (void *line, l_int32 n)
 
l_int32 l_getDataByte (void *line, l_int32 n)
 
void l_setDataByte (void *line, l_int32 n, l_int32 val)
 
l_int32 l_getDataTwoBytes (void *line, l_int32 n)
 
void l_setDataTwoBytes (void *line, l_int32 n, l_int32 val)
 
l_int32 l_getDataFourBytes (void *line, l_int32 n)
 
void l_setDataFourBytes (void *line, l_int32 n, l_int32 val)
 

Detailed Description

Access within an array of 32-bit words

      l_int32     l_getDataBit()
      void        l_setDataBit()
      void        l_clearDataBit()
      void        l_setDataBitVal()
      l_int32     l_getDataDibit()
      void        l_setDataDibit()
      void        l_clearDataDibit()
      l_int32     l_getDataQbit()
      void        l_setDataQbit()
      void        l_clearDataQbit()
      l_int32     l_getDataByte()
      void        l_setDataByte()
      l_int32     l_getDataTwoBytes()
      void        l_setDataTwoBytes()
      l_int32     l_getDataFourBytes()
      void        l_setDataFourBytes()

Note that these all require 32-bit alignment, and hence an input
ptr to l_uint32.  However, this is not enforced by the compiler.
Instead, we allow the use of a void* ptr, because the line ptrs
are an efficient way to get random access (see pixGetLinePtrs()).
It is then necessary to cast internally within each function
because ptr arithmetic requires knowing the size of the units
being referenced.

Definition in file arrayaccess.c.

Function Documentation

◆ l_clearDataBit()

void l_clearDataBit ( void *  line,
l_int32  n 
)

l_clearDataBit()

Parameters
[in]lineptr to beginning of data line
[in]npixel index
Returns
void

Action: sets the 1-bit pixel to 0

Definition at line 108 of file arrayaccess.c.

◆ l_clearDataDibit()

void l_clearDataDibit ( void *  line,
l_int32  n 
)

l_clearDataDibit()

Parameters
[in]lineptr to beginning of data line
[in]npixel index
Returns
void

Action: sets the 2-bit pixel to 0

Definition at line 194 of file arrayaccess.c.

◆ l_clearDataQbit()

void l_clearDataQbit ( void *  line,
l_int32  n 
)

l_clearDataQbit()

Parameters
[in]lineptr to beginning of data line
[in]npixel index
Returns
void

Action: sets the 4-bit pixel to 0

Definition at line 248 of file arrayaccess.c.

◆ l_getDataBit()

l_int32 l_getDataBit ( void *  line,
l_int32  n 
)

l_getDataBit()

Parameters
[in]lineptr to beginning of data line
[in]npixel index
Returns
val of the nth 1-bit pixel.

Definition at line 74 of file arrayaccess.c.

◆ l_getDataByte()

l_int32 l_getDataByte ( void *  line,
l_int32  n 
)

l_getDataByte()

Parameters
[in]lineptr to beginning of data line
[in]npixel index
Returns
value of the n-th byte pixel

Definition at line 263 of file arrayaccess.c.

◆ l_getDataDibit()

l_int32 l_getDataDibit ( void *  line,
l_int32  n 
)

l_getDataDibit()

Parameters
[in]lineptr to beginning of data line
[in]npixel index
Returns
val of the nth 2-bit pixel.

Definition at line 155 of file arrayaccess.c.

◆ l_getDataFourBytes()

l_int32 l_getDataFourBytes ( void *  line,
l_int32  n 
)

l_getDataFourBytes()

Parameters
[in]lineptr to beginning of data line
[in]npixel index
Returns
value of the n-th 4-byte pixel

Definition at line 343 of file arrayaccess.c.

Referenced by l_uncompressGrayHistograms().

◆ l_getDataQbit()

l_int32 l_getDataQbit ( void *  line,
l_int32  n 
)

l_getDataQbit()

Parameters
[in]lineptr to beginning of data line
[in]npixel index
Returns
val of the nth 4-bit pixel.

Definition at line 209 of file arrayaccess.c.

◆ l_getDataTwoBytes()

l_int32 l_getDataTwoBytes ( void *  line,
l_int32  n 
)

l_getDataTwoBytes()

Parameters
[in]lineptr to beginning of data line
[in]npixel index
Returns
value of the n-th 2-byte pixel

Definition at line 303 of file arrayaccess.c.

◆ l_setDataBit()

void l_setDataBit ( void *  line,
l_int32  n 
)

l_setDataBit()

Parameters
[in]lineptr to beginning of data line
[in]npixel index
Returns
void

Action: sets the pixel to 1

Definition at line 91 of file arrayaccess.c.

◆ l_setDataBitVal()

void l_setDataBitVal ( void *  line,
l_int32  n,
l_int32  val 
)

l_setDataBitVal()

Parameters
[in]lineptr to beginning of data line
[in]npixel index
[in]valval to be inserted: 0 or 1
Returns
void
Notes:
     (1) This is an accessor for a 1 bpp pix.
     (2) It is actually a little slower than using:
           if (val == 0)
               l_ClearDataBit(line, n);
           else
               l_SetDataBit(line, n);

Definition at line 134 of file arrayaccess.c.

◆ l_setDataByte()

void l_setDataByte ( void *  line,
l_int32  n,
l_int32  val 
)

l_setDataByte()

Parameters
[in]lineptr to beginning of data line
[in]npixel index
[in]valval to be inserted: 0 - 0xff
Returns
void

Definition at line 283 of file arrayaccess.c.

◆ l_setDataDibit()

void l_setDataDibit ( void *  line,
l_int32  n,
l_int32  val 
)

l_setDataDibit()

Parameters
[in]lineptr to beginning of data line
[in]npixel index
[in]valval to be inserted: 0 - 3
Returns
void

Definition at line 171 of file arrayaccess.c.

◆ l_setDataFourBytes()

void l_setDataFourBytes ( void *  line,
l_int32  n,
l_int32  val 
)

l_setDataFourBytes()

Parameters
[in]lineptr to beginning of data line
[in]npixel index
[in]valval to be inserted: 0 - 0xffffffff
Returns
void

Definition at line 359 of file arrayaccess.c.

Referenced by l_compressGrayHistograms().

◆ l_setDataQbit()

void l_setDataQbit ( void *  line,
l_int32  n,
l_int32  val 
)

l_setDataQbit()

Parameters
[in]lineptr to beginning of data line
[in]npixel index
[in]valval to be inserted: 0 - 0xf
Returns
void

Definition at line 225 of file arrayaccess.c.

◆ l_setDataTwoBytes()

void l_setDataTwoBytes ( void *  line,
l_int32  n,
l_int32  val 
)

l_setDataTwoBytes()

Parameters
[in]lineptr to beginning of data line
[in]npixel index
[in]valval to be inserted: 0 - 0xffff
Returns
void

Definition at line 323 of file arrayaccess.c.