cdesktopenv/cde/lib/DtHelp/il/ilcomppackbits.c

271 lines
11 KiB
C

/*
* CDE - Common Desktop Environment
*
* Copyright (c) 1993-2012, The Open Group. All rights reserved.
*
* These libraries and programs are free software; you can
* redistribute them and/or modify them under the terms of the GNU
* Lesser General Public License as published by the Free Software
* Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* These libraries and programs are distributed in the hope that
* they will be useful, but WITHOUT ANY WARRANTY; without even the
* implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
* PURPOSE. See the GNU Lesser General Public License for more
* details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with these libraries and programs; if not, write
* to the Free Software Foundation, Inc., 51 Franklin Street, Fifth
* Floor, Boston, MA 02110-1301 USA
*/
/* $XConsortium: ilcomppackbits.c /main/3 1995/10/23 15:42:43 rswiston $ */
/**---------------------------------------------------------------------
***
*** (c)Copyright 1991 Hewlett-Packard Co.
***
*** RESTRICTED RIGHTS LEGEND
*** Use, duplication, or disclosure by the U.S. Government is subject to
*** restrictions as set forth in sub-paragraph (c)(1)(ii) of the Rights in
*** Technical Data and Computer Software clause in DFARS 252.227-7013.
*** Hewlett-Packard Company
*** 3000 Hanover Street
*** Palo Alto, CA 94304 U.S.A.
*** Rights for non-DOD U.S. Government Departments and Agencies are as set
*** forth in FAR 52.227-19(c)(1,2).
***
***-------------------------------------------------------------------*/
#include "ilint.h"
#include "ilpipelem.h"
#include "ilcompress.h"
#include "ilerrors.h"
/* ========================================================================
Compression private data structure definition
======================================================================== */
typedef struct {
int stripHeight;
int height;
int width;
int widthbytes;
int beingRecalled;
ilBool firstStrip;
} ilCompPBPrivRec, *ilCompPBPrivPtr;
/* ========================================================================
-------------------- ilComppackbitsInit -------------------
======================================================================== */
static ilError ilComppackbitsInit(
ilCompPBPrivPtr pPrivate,
ilImageInfo *pSrcImage,
ilImageInfo *pDstImage
)
{
pPrivate->firstStrip = TRUE;
return IL_OK;
}
/* End ilComppackbitsInit() */
/* ========================================================================
-------------------- ilComppackbitsExecute() -------------------
======================================================================== */
static ilError ilComppackbitsExecute(
ilExecuteData *pData,
unsigned long dstLine,
unsigned long *pNLines
)
{
#define PB_MAX_BUFFER_WRITE 140 /* max bytes written after check for room in compressed buffer */
unsigned long nBytes = 0; /* Number of source image bytes to unpack for current strip */
unsigned long nLines; /* Number of lines per source image strip */
ilPtr pSrcByte; /* Pointer to source image data first byte */
ilPtr pSrcLine; /* Pointer to source image data first byte of line */
ilPtr pDstByte; /* Pointer to destination image data */
ilPtr pDstBufferEnd; /* Ptr to byte "PB_MAX_BUFFER_WRITE" from end of compressed buffer */
unsigned long srcNBytes; /* Number of source image bytes per row */
ilCompPBPrivPtr pPriv; /* Pointer to private image data */
ilImagePlaneInfo *pSrcPlane, *pDstPlane;
long offset; /* difference between current dst image address pointer and the
start address of the dst image buffer */
long length; /* number of bytes written to dst image */
int count; /* run count value */
int start, j; /* indices into source data */
int nBytesM1; /* bytes per row of data minus one */
/* ========================================================================
Set up for execution of compression algorithm code
======================================================================== */
pPriv = (ilCompPBPrivPtr) pData->pPrivate;
nLines = *pNLines;
if (nLines <= 0) return IL_OK;
pSrcPlane = &pData->pSrcImage->plane[0];
srcNBytes = pSrcPlane->nBytesPerRow;
pSrcLine = pSrcPlane->pPixels + pData->srcLine * srcNBytes;
/* allocate destination buffer space */
if (pPriv->firstStrip) {
if (!_ilReallocCompressedBuffer (pData->pDstImage, 0, PB_MAX_BUFFER_WRITE))
return IL_ERROR_MALLOC;
pPriv->firstStrip = FALSE;
}
pDstPlane = &pData->pDstImage->plane[0];
pDstBufferEnd = pDstPlane->pPixels + (pDstPlane->bufferSize - PB_MAX_BUFFER_WRITE);
/* exit. Pointer pPixels must not be NULL */
if (!pDstPlane->pPixels) return IL_ERROR_NULL_COMPRESSED_IMAGE;
pDstByte = pDstPlane->pPixels + *pData->compressed.pDstOffset;
/* write out image, one strip at a time */
nBytesM1 = pPriv->widthbytes - 1;
while ( nLines-- > 0 ) {
pSrcByte = pSrcLine;
start = 0;
j = 0;
while (j <= nBytesM1) {
start = j;
if ( pSrcByte[j] == pSrcByte[j+1] ) { /* repeat run */
while ((pSrcByte[j] == pSrcByte[j+1]) && (j < nBytesM1) && ((j-start) < 127) ) j++;
/* output buffer size handling code */
if (pDstByte >= pDstBufferEnd) {
offset = pDstByte - pDstPlane->pPixels;
if (!_ilReallocCompressedBuffer (pData->pDstImage, 0, offset + PB_MAX_BUFFER_WRITE))
return IL_ERROR_MALLOC;
pDstByte = pDstPlane->pPixels + offset;
pDstBufferEnd = pDstPlane->pPixels + (pDstPlane->bufferSize - PB_MAX_BUFFER_WRITE);
}
j++;
count = 1 - (j-start);
*pDstByte++ = count;
*pDstByte++ = pSrcByte[j-1];
}
else { /* literal run */
while ( (pSrcByte[j] != pSrcByte[j+1]) && (j <= nBytesM1) && ((j-start) < 128) ) j++;
/* output buffer size handling code */
if (pDstByte >= pDstBufferEnd) {
offset = pDstByte - pDstPlane->pPixels;
if (!_ilReallocCompressedBuffer (pData->pDstImage, 0, offset + PB_MAX_BUFFER_WRITE))
return IL_ERROR_MALLOC;
pDstByte = pDstPlane->pPixels + offset;
pDstBufferEnd = pDstPlane->pPixels + (pDstPlane->bufferSize - PB_MAX_BUFFER_WRITE);
}
count = j-start - 1;
*pDstByte++ = count;
do {
*pDstByte++ = pSrcByte[start++];
} while (--count >= 0);
}
} /* end row loop */
pSrcLine += srcNBytes;
} /* end while */
/* Return the number of bytes written, = dst ptr - beginning of dst buffer */
*pData->compressed.pNBytesWritten = pDstByte - (pDstPlane->pPixels + *pData->compressed.pDstOffset);
return IL_OK;
}
/* ========================================================================
-------------------- ilCompressPackbits --------------------
======================================================================== */
IL_PRIVATE ilBool _ilCompressPackbits (
ilPipe pipe,
ilPipeInfo *pinfo,
ilImageDes *pimdes,
ilImageFormat *pimformat,
ilSrcElementData *pSrcData
)
{
ilDstElementData dstdata;
ilCompPBPrivPtr pPriv;
ilImageDes des;
ilBool bitPerPixel;
/* Validate that image is bit/pixel, or if not bit, convert to byte if fits. */
if (pimdes->nSamplesPerPixel != 1)
return ilDeclarePipeInvalid (pipe, IL_ERROR_IMAGE_TYPE);
if (pimformat->nBitsPerSample[0] == 1)
bitPerPixel = TRUE;
else {
bitPerPixel = FALSE;
if (pimformat->nBitsPerSample[0] != 8)
if (!ilConvert (pipe, (ilImageDes *)NULL, IL_FORMAT_BYTE, 0, (ilPtr)NULL))
return FALSE;
}
/* dstdata describes strips being output to next pipe element */
dstdata.producerObject = (ilObject) NULL;
des = *pimdes;
des.compression = IL_PACKBITS;
dstdata.pDes = &des;
dstdata.pFormat = (bitPerPixel) ? IL_FORMAT_BIT : IL_FORMAT_BYTE;
dstdata.width = pinfo->width;
dstdata.height = pinfo->height;
dstdata.stripHeight = pSrcData->stripHeight;
dstdata.constantStrip = pSrcData->constantStrip;
dstdata.pPalette = pinfo->pPalette;
dstdata.pCompData = (ilPtr)NULL;
/* ========================================================================
Add the filter to the pipeline
======================================================================== */
pPriv = (ilCompPBPrivPtr) ilAddPipeElement(pipe, IL_FILTER, sizeof(ilCompPBPrivRec), 0, pSrcData, &dstdata,
ilComppackbitsInit, IL_NPF, IL_NPF, ilComppackbitsExecute, 0);
if (!pPriv) return FALSE; /* EXIT */
/* save private date */
pPriv->stripHeight = dstdata.stripHeight;
pPriv->height = pinfo->height;
pPriv->width = pinfo->width;
pPriv->widthbytes = (bitPerPixel) ? (pPriv->width + 7) / 8 : pPriv->width;
pPriv->beingRecalled = FALSE;
return TRUE;
}