ultimatepp/bazaar/plugin/gdal/alg/gdalmediancut.cpp
cxl 23ff1e7e82 .gdal moved to bazaar
git-svn-id: svn://ultimatepp.org/upp/trunk@9273 f0d560ea-af0d-0410-9eb7-867de7ffcac7
2015-12-07 13:36:24 +00:00

1126 lines
39 KiB
C++

/******************************************************************************
* $Id: gdalmediancut.cpp 28085 2014-12-07 14:36:00Z rouault $
*
* Project: CIETMap Phase 2
* Purpose: Use median cut algorithm to generate an near-optimal PCT for a
* given RGB image. Implemented as function GDALComputeMedianCutPCT.
* Author: Frank Warmerdam, warmerdam@pobox.com
*
******************************************************************************
* Copyright (c) 2001, Frank Warmerdam
* Copyright (c) 2007-2010, Even Rouault <even dot rouault at mines-paris dot org>
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
******************************************************************************
*
* This code was based on the tiffmedian.c code from libtiff (www.libtiff.org)
* which was based on a paper by Paul Heckbert:
*
* "Color Image Quantization for Frame Buffer Display", Paul
* Heckbert, SIGGRAPH proceedings, 1982, pp. 297-307.
*
*/
#include "gdal_priv.h"
#include "gdal_alg.h"
#include "gdal_alg_priv.h"
CPL_CVSID("$Id: gdalmediancut.cpp 28085 2014-12-07 14:36:00Z rouault $");
#define HISTOGRAM(h,n,r,g,b) h[((r)*(n)+(g))*(n)+(b)]
#define MAKE_COLOR_CODE(r,g,b) ((r)+(g)*256+(b)*256*256)
typedef struct /* NOTE: if changing the size of this structure, edit MEDIAN_CUT_AND_DITHER_BUFFER_SIZE_65536 */
{
GUInt32 nColorCode;
int nCount;
GUInt32 nColorCode2;
int nCount2;
GUInt32 nColorCode3;
int nCount3;
} HashHistogram;
typedef struct colorbox {
struct colorbox *next, *prev;
int rmin, rmax;
int gmin, gmax;
int bmin, bmax;
int total;
} Colorbox;
static void splitbox(Colorbox* ptr, const int* histogram,
const HashHistogram* psHashHistogram,
int nCLevels,
Colorbox **pfreeboxes, Colorbox **pusedboxes,
GByte* pabyRedBand,
GByte* pabyGreenBand,
GByte* pabyBlueBand, int nPixels);
static void shrinkbox(Colorbox* box,
const int* histogram,
int nCLevels);
static Colorbox* largest_box(Colorbox *usedboxes);
/************************************************************************/
/* GDALComputeMedianCutPCT() */
/************************************************************************/
/**
* Compute optimal PCT for RGB image.
*
* This function implements a median cut algorithm to compute an "optimal"
* pseudocolor table for representing an input RGB image. This PCT could
* then be used with GDALDitherRGB2PCT() to convert a 24bit RGB image into
* an eightbit pseudo-colored image.
*
* This code was based on the tiffmedian.c code from libtiff (www.libtiff.org)
* which was based on a paper by Paul Heckbert:
*
* \verbatim
* "Color Image Quantization for Frame Buffer Display", Paul
* Heckbert, SIGGRAPH proceedings, 1982, pp. 297-307.
* \endverbatim
*
* The red, green and blue input bands do not necessarily need to come
* from the same file, but they must be the same width and height. They will
* be clipped to 8bit during reading, so non-eight bit bands are generally
* inappropriate.
*
* @param hRed Red input band.
* @param hGreen Green input band.
* @param hBlue Blue input band.
* @param pfnIncludePixel function used to test which pixels should be included
* in the analysis. At this time this argument is ignored and all pixels are
* utilized. This should normally be NULL.
* @param nColors the desired number of colors to be returned (2-256).
* @param hColorTable the colors will be returned in this color table object.
* @param pfnProgress callback for reporting algorithm progress matching the
* GDALProgressFunc() semantics. May be NULL.
* @param pProgressArg callback argument passed to pfnProgress.
*
* @return returns CE_None on success or CE_Failure if an error occurs.
*/
extern "C" int CPL_STDCALL
GDALComputeMedianCutPCT( GDALRasterBandH hRed,
GDALRasterBandH hGreen,
GDALRasterBandH hBlue,
int (*pfnIncludePixel)(int,int,void*),
int nColors,
GDALColorTableH hColorTable,
GDALProgressFunc pfnProgress,
void * pProgressArg )
{
return GDALComputeMedianCutPCTInternal(hRed, hGreen, hBlue,
NULL, NULL, NULL,
pfnIncludePixel, nColors,
5,
NULL,
hColorTable,
pfnProgress, pProgressArg);
}
/*static int nMaxCollisions = 0;*/
static inline int FindColorCount(const HashHistogram* psHashHistogram,
GUInt32 nColorCode)
{
GUInt32 nIdx = nColorCode % PRIME_FOR_65536;
/*int nCollisions = 0; */
while( TRUE )
{
if( (int)psHashHistogram[nIdx].nColorCode < 0 )
{
return 0;
}
if( psHashHistogram[nIdx].nColorCode == nColorCode )
{
return psHashHistogram[nIdx].nCount;
}
if( (int)psHashHistogram[nIdx].nColorCode2 < 0 )
{
return 0;
}
if( psHashHistogram[nIdx].nColorCode2 == nColorCode )
{
return psHashHistogram[nIdx].nCount2;
}
if( (int)psHashHistogram[nIdx].nColorCode3 < 0 )
{
return 0;
}
if( psHashHistogram[nIdx].nColorCode3 == nColorCode )
{
return psHashHistogram[nIdx].nCount3;
}
do
{
/*nCollisions ++;*/
nIdx+=257;
if( nIdx >= PRIME_FOR_65536 )
nIdx -= PRIME_FOR_65536;
}
while( (int)psHashHistogram[nIdx].nColorCode >= 0 &&
psHashHistogram[nIdx].nColorCode != nColorCode &&
(int)psHashHistogram[nIdx].nColorCode2 >= 0 &&
psHashHistogram[nIdx].nColorCode2 != nColorCode&&
(int)psHashHistogram[nIdx].nColorCode3 >= 0 &&
psHashHistogram[nIdx].nColorCode3 != nColorCode );
/*if( nCollisions > nMaxCollisions )
{
nMaxCollisions = nCollisions;
printf("median cut: nCollisions = %d for R=%d,G=%d,B=%d\n",
nCollisions, nColorCode&0xFF, (nColorCode>>8)&0xFF, (nColorCode>>16)&0xFF);
}*/
}
}
static inline int* FindAndInsertColorCount(HashHistogram* psHashHistogram,
GUInt32 nColorCode)
{
GUInt32 nIdx = nColorCode % PRIME_FOR_65536;
/*int nCollisions = 0;*/
while( TRUE )
{
if( psHashHistogram[nIdx].nColorCode == nColorCode )
{
return &(psHashHistogram[nIdx].nCount);
}
if( (int)psHashHistogram[nIdx].nColorCode < 0 )
{
psHashHistogram[nIdx].nColorCode = nColorCode;
psHashHistogram[nIdx].nCount = 0;
return &(psHashHistogram[nIdx].nCount);
}
if( psHashHistogram[nIdx].nColorCode2 == nColorCode )
{
return &(psHashHistogram[nIdx].nCount2);
}
if( (int)psHashHistogram[nIdx].nColorCode2 < 0 )
{
psHashHistogram[nIdx].nColorCode2 = nColorCode;
psHashHistogram[nIdx].nCount2 = 0;
return &(psHashHistogram[nIdx].nCount2);
}
if( psHashHistogram[nIdx].nColorCode3 == nColorCode )
{
return &(psHashHistogram[nIdx].nCount3);
}
if( (int)psHashHistogram[nIdx].nColorCode3 < 0 )
{
psHashHistogram[nIdx].nColorCode3 = nColorCode;
psHashHistogram[nIdx].nCount3 = 0;
return &(psHashHistogram[nIdx].nCount3);
}
do
{
/*nCollisions ++;*/
nIdx+=257;
if( nIdx >= PRIME_FOR_65536 )
nIdx -= PRIME_FOR_65536;
}
while( (int)psHashHistogram[nIdx].nColorCode >= 0 &&
psHashHistogram[nIdx].nColorCode != nColorCode &&
(int)psHashHistogram[nIdx].nColorCode2 >= 0 &&
psHashHistogram[nIdx].nColorCode2 != nColorCode&&
(int)psHashHistogram[nIdx].nColorCode3 >= 0 &&
psHashHistogram[nIdx].nColorCode3 != nColorCode );
/*if( nCollisions > nMaxCollisions )
{
nMaxCollisions = nCollisions;
printf("median cut: nCollisions = %d for R=%d,G=%d,B=%d\n",
nCollisions, nColorCode&0xFF, (nColorCode>>8)&0xFF, (nColorCode>>16)&0xFF);
}*/
}
}
int
GDALComputeMedianCutPCTInternal( GDALRasterBandH hRed,
GDALRasterBandH hGreen,
GDALRasterBandH hBlue,
GByte* pabyRedBand,
GByte* pabyGreenBand,
GByte* pabyBlueBand,
int (*pfnIncludePixel)(int,int,void*),
int nColors,
int nBits,
int* panHistogram, /* NULL, or at least of size (1<<nBits)^3 * sizeof(int) bytes */
GDALColorTableH hColorTable,
GDALProgressFunc pfnProgress,
void * pProgressArg )
{
VALIDATE_POINTER1( hRed, "GDALComputeMedianCutPCT", CE_Failure );
VALIDATE_POINTER1( hGreen, "GDALComputeMedianCutPCT", CE_Failure );
VALIDATE_POINTER1( hBlue, "GDALComputeMedianCutPCT", CE_Failure );
int nXSize, nYSize;
CPLErr err = CE_None;
/* -------------------------------------------------------------------- */
/* Validate parameters. */
/* -------------------------------------------------------------------- */
nXSize = GDALGetRasterBandXSize( hRed );
nYSize = GDALGetRasterBandYSize( hRed );
if( GDALGetRasterBandXSize( hGreen ) != nXSize
|| GDALGetRasterBandYSize( hGreen ) != nYSize
|| GDALGetRasterBandXSize( hBlue ) != nXSize
|| GDALGetRasterBandYSize( hBlue ) != nYSize )
{
CPLError( CE_Failure, CPLE_IllegalArg,
"Green or blue band doesn't match size of red band.\n" );
return CE_Failure;
}
if( pfnIncludePixel != NULL )
{
CPLError( CE_Failure, CPLE_IllegalArg,
"GDALComputeMedianCutPCT() doesn't currently support "
" pfnIncludePixel function." );
return CE_Failure;
}
if ( nColors <= 0 )
{
CPLError( CE_Failure, CPLE_IllegalArg,
"GDALComputeMedianCutPCT() : nColors must be strictly greater than 1." );
return CE_Failure;
}
if ( nColors > 256 )
{
CPLError( CE_Failure, CPLE_IllegalArg,
"GDALComputeMedianCutPCT() : nColors must be lesser than or equal to 256." );
return CE_Failure;
}
if( pfnProgress == NULL )
pfnProgress = GDALDummyProgress;
/* ==================================================================== */
/* STEP 1: create empty boxes. */
/* ==================================================================== */
int i;
Colorbox *box_list, *ptr;
int* histogram;
Colorbox *freeboxes;
Colorbox *usedboxes;
int nCLevels = 1 << nBits;
int nColorShift = 8 - nBits;
int nColorCounter = 0;
GByte anRed[256], anGreen[256], anBlue[256];
int nPixels = 0;
HashHistogram* psHashHistogram = NULL;
if( nBits == 8 && pabyRedBand != NULL && pabyGreenBand != NULL &&
pabyBlueBand != NULL && nXSize < INT_MAX / nYSize )
{
nPixels = nXSize * nYSize;
}
if( panHistogram )
{
if( nBits == 8 && (GIntBig)nXSize * nYSize <= 65536 )
{
/* If the image is small enough, then the number of colors */
/* will be limited and using a hashmap, rather than a full table */
/* will be more efficient */
histogram = NULL;
psHashHistogram = (HashHistogram*)panHistogram;
memset(psHashHistogram, 0xFF, sizeof(HashHistogram) * PRIME_FOR_65536);
}
else
{
histogram = panHistogram;
memset(histogram, 0, nCLevels*nCLevels*nCLevels * sizeof(int));
}
}
else
{
histogram = (int*) VSICalloc(nCLevels*nCLevels*nCLevels,sizeof(int));
if( histogram == NULL )
{
CPLError( CE_Failure, CPLE_OutOfMemory,
"VSICalloc(): Out of memory in GDALComputeMedianCutPCT" );
return CE_Failure;
}
}
usedboxes = NULL;
box_list = freeboxes = (Colorbox *)CPLMalloc(nColors*sizeof (Colorbox));
freeboxes[0].next = &freeboxes[1];
freeboxes[0].prev = NULL;
for (i = 1; i < nColors-1; ++i) {
freeboxes[i].next = &freeboxes[i+1];
freeboxes[i].prev = &freeboxes[i-1];
}
freeboxes[nColors-1].next = NULL;
freeboxes[nColors-1].prev = &freeboxes[nColors-2];
/* ==================================================================== */
/* Build histogram. */
/* ==================================================================== */
GByte *pabyRedLine, *pabyGreenLine, *pabyBlueLine;
int iLine, iPixel;
/* -------------------------------------------------------------------- */
/* Initialize the box datastructures. */
/* -------------------------------------------------------------------- */
ptr = freeboxes;
freeboxes = ptr->next;
if (freeboxes)
freeboxes->prev = NULL;
ptr->next = usedboxes;
usedboxes = ptr;
if (ptr->next)
ptr->next->prev = ptr;
ptr->rmin = ptr->gmin = ptr->bmin = 999;
ptr->rmax = ptr->gmax = ptr->bmax = -1;
ptr->total = nXSize * nYSize;
/* -------------------------------------------------------------------- */
/* Collect histogram. */
/* -------------------------------------------------------------------- */
pabyRedLine = (GByte *) VSIMalloc(nXSize);
pabyGreenLine = (GByte *) VSIMalloc(nXSize);
pabyBlueLine = (GByte *) VSIMalloc(nXSize);
if (pabyRedLine == NULL ||
pabyGreenLine == NULL ||
pabyBlueLine == NULL)
{
CPLError( CE_Failure, CPLE_OutOfMemory,
"VSIMalloc(): Out of memory in GDALComputeMedianCutPCT" );
err = CE_Failure;
goto end_and_cleanup;
}
for( iLine = 0; iLine < nYSize; iLine++ )
{
if( !pfnProgress( iLine / (double) nYSize,
"Generating Histogram", pProgressArg ) )
{
CPLError( CE_Failure, CPLE_UserInterrupt, "User Terminated" );
err = CE_Failure;
goto end_and_cleanup;
}
GDALRasterIO( hRed, GF_Read, 0, iLine, nXSize, 1,
pabyRedLine, nXSize, 1, GDT_Byte, 0, 0 );
GDALRasterIO( hGreen, GF_Read, 0, iLine, nXSize, 1,
pabyGreenLine, nXSize, 1, GDT_Byte, 0, 0 );
GDALRasterIO( hBlue, GF_Read, 0, iLine, nXSize, 1,
pabyBlueLine, nXSize, 1, GDT_Byte, 0, 0 );
for( iPixel = 0; iPixel < nXSize; iPixel++ )
{
int nRed, nGreen, nBlue;
nRed = pabyRedLine[iPixel] >> nColorShift;
nGreen = pabyGreenLine[iPixel] >> nColorShift;
nBlue = pabyBlueLine[iPixel] >> nColorShift;
ptr->rmin = MIN(ptr->rmin, nRed);
ptr->gmin = MIN(ptr->gmin, nGreen);
ptr->bmin = MIN(ptr->bmin, nBlue);
ptr->rmax = MAX(ptr->rmax, nRed);
ptr->gmax = MAX(ptr->gmax, nGreen);
ptr->bmax = MAX(ptr->bmax, nBlue);
int* pnColor;
if( psHashHistogram )
{
pnColor = FindAndInsertColorCount(psHashHistogram,
MAKE_COLOR_CODE(nRed, nGreen, nBlue));
}
else
{
pnColor = &HISTOGRAM(histogram, nCLevels, nRed, nGreen, nBlue);
}
if( *pnColor == 0 )
{
if( nColorShift == 0 && nColorCounter < nColors )
{
anRed[nColorCounter] = nRed;
anGreen[nColorCounter] = nGreen;
anBlue[nColorCounter] = nBlue;
}
nColorCounter++;
}
(*pnColor) ++;
}
}
if( !pfnProgress( 1.0, "Generating Histogram", pProgressArg ) )
{
CPLError( CE_Failure, CPLE_UserInterrupt, "User Terminated" );
err = CE_Failure;
goto end_and_cleanup;
}
if( nColorShift == 0 && nColorCounter <= nColors )
{
//CPLDebug("MEDIAN_CUT", "%d colors found <= %d", nColorCounter, nColors);
for(int iColor = 0;iColor<nColorCounter;iColor++)
{
GDALColorEntry sEntry;
sEntry.c1 = (GByte) anRed[iColor];
sEntry.c2 = (GByte) anGreen[iColor];
sEntry.c3 = (GByte) anBlue[iColor];
sEntry.c4 = 255;
GDALSetColorEntry( hColorTable, iColor, &sEntry );
}
goto end_and_cleanup;
}
/* ==================================================================== */
/* STEP 3: continually subdivide boxes until no more free */
/* boxes remain or until all colors assigned. */
/* ==================================================================== */
while (freeboxes != NULL) {
ptr = largest_box(usedboxes);
if (ptr != NULL)
splitbox(ptr, histogram, psHashHistogram, nCLevels, &freeboxes, &usedboxes,
pabyRedBand, pabyGreenBand, pabyBlueBand, nPixels);
else
freeboxes = NULL;
}
/* ==================================================================== */
/* STEP 4: assign colors to all boxes */
/* ==================================================================== */
for (i = 0, ptr = usedboxes; ptr != NULL; ++i, ptr = ptr->next)
{
GDALColorEntry sEntry;
sEntry.c1 = (GByte) (((ptr->rmin + ptr->rmax) << nColorShift) / 2);
sEntry.c2 = (GByte) (((ptr->gmin + ptr->gmax) << nColorShift) / 2);
sEntry.c3 = (GByte) (((ptr->bmin + ptr->bmax) << nColorShift) / 2);
sEntry.c4 = 255;
GDALSetColorEntry( hColorTable, i, &sEntry );
}
end_and_cleanup:
CPLFree( pabyRedLine );
CPLFree( pabyGreenLine );
CPLFree( pabyBlueLine );
/* We're done with the boxes now */
CPLFree(box_list);
freeboxes = usedboxes = NULL;
if( panHistogram == NULL )
CPLFree( histogram );
return err;
}
/************************************************************************/
/* largest_box() */
/************************************************************************/
static Colorbox *
largest_box(Colorbox *usedboxes)
{
Colorbox *p, *b;
int size;
b = NULL;
size = -1;
for (p = usedboxes; p != NULL; p = p->next)
if ((p->rmax > p->rmin || p->gmax > p->gmin ||
p->bmax > p->bmin) && p->total > size)
size = (b = p)->total;
return (b);
}
static void shrinkboxFromBand(Colorbox* ptr,
const GByte* pabyRedBand,
const GByte* pabyGreenBand,
const GByte* pabyBlueBand, int nPixels)
{
int rmin_new = 255, rmax_new = 0,
gmin_new = 255, gmax_new = 0,
bmin_new = 255, bmax_new = 0;
for(int i=0;i<nPixels;i++)
{
int iR = pabyRedBand[i];
int iG = pabyGreenBand[i];
int iB = pabyBlueBand[i];
if( iR >= ptr->rmin && iR <= ptr->rmax &&
iG >= ptr->gmin && iG <= ptr->gmax &&
iB >= ptr->bmin && iB <= ptr->bmax )
{
if( iR < rmin_new ) rmin_new = iR;
if( iR > rmax_new ) rmax_new = iR;
if( iG < gmin_new ) gmin_new = iG;
if( iG > gmax_new ) gmax_new = iG;
if( iB < bmin_new ) bmin_new = iB;
if( iB > bmax_new ) bmax_new = iB;
}
}
CPLAssert(rmin_new >= ptr->rmin && rmin_new <= rmax_new && rmax_new <= ptr->rmax);
CPLAssert(gmin_new >= ptr->gmin && gmin_new <= gmax_new && gmax_new <= ptr->gmax);
CPLAssert(bmin_new >= ptr->bmin && bmin_new <= bmax_new && bmax_new <= ptr->bmax);
ptr->rmin = rmin_new;
ptr->rmax = rmax_new;
ptr->gmin = gmin_new;
ptr->gmax = gmax_new;
ptr->bmin = bmin_new;
ptr->bmax = bmax_new;
}
static void shrinkboxFromHashHistogram(Colorbox* box,
const HashHistogram* psHashHistogram)
{
int ir, ig, ib;
//int count_iter;
if (box->rmax > box->rmin) {
//count_iter = 0;
for (ir = box->rmin; ir <= box->rmax; ++ir) {
for (ig = box->gmin; ig <= box->gmax; ++ig) {
for (ib = box->bmin; ib <= box->bmax; ++ib) {
//count_iter ++;
if (FindColorCount(psHashHistogram,
MAKE_COLOR_CODE(ir, ig, ib)) != 0) {
//if( count_iter > 65536 ) printf("iter rmin=%d\n", count_iter);
box->rmin = ir;
goto have_rmin;
}
}
}
}
}
have_rmin:
if (box->rmax > box->rmin) {
//count_iter = 0;
for (ir = box->rmax; ir >= box->rmin; --ir) {
for (ig = box->gmin; ig <= box->gmax; ++ig) {
ib = box->bmin;
for (; ib <= box->bmax; ++ib) {
//count_iter ++;
if (FindColorCount(psHashHistogram,
MAKE_COLOR_CODE(ir, ig, ib)) != 0) {
//if( count_iter > 65536 ) printf("iter rmax=%d\n", count_iter);
box->rmax = ir;
goto have_rmax;
}
}
}
}
}
have_rmax:
if (box->gmax > box->gmin) {
//count_iter = 0;
for (ig = box->gmin; ig <= box->gmax; ++ig) {
for (ir = box->rmin; ir <= box->rmax; ++ir) {
for (ib = box->bmin; ib <= box->bmax; ++ib) {
//count_iter ++;
if (FindColorCount(psHashHistogram,
MAKE_COLOR_CODE(ir, ig, ib)) != 0) {
//if( count_iter > 65536 ) printf("iter gmin=%d\n", count_iter);
box->gmin = ig;
goto have_gmin;
}
}
}
}
}
have_gmin:
if (box->gmax > box->gmin) {
//count_iter = 0;
for (ig = box->gmax; ig >= box->gmin; --ig) {
for (ir = box->rmin; ir <= box->rmax; ++ir) {
ib = box->bmin;
for (; ib <= box->bmax; ++ib) {
//count_iter ++;
if (FindColorCount(psHashHistogram,
MAKE_COLOR_CODE(ir, ig, ib)) != 0) {
//if( count_iter > 65536 ) printf("iter gmax=%d\n", count_iter);
box->gmax = ig;
goto have_gmax;
}
}
}
}
}
have_gmax:
if (box->bmax > box->bmin) {
//count_iter = 0;
for (ib = box->bmin; ib <= box->bmax; ++ib) {
for (ir = box->rmin; ir <= box->rmax; ++ir) {
for (ig = box->gmin; ig <= box->gmax; ++ig) {
//count_iter ++;
if (FindColorCount(psHashHistogram,
MAKE_COLOR_CODE(ir, ig, ib)) != 0) {
//if( count_iter > 65536 ) printf("iter bmin=%d\n", count_iter);
box->bmin = ib;
goto have_bmin;
}
}
}
}
}
have_bmin:
if (box->bmax > box->bmin) {
//count_iter = 0;
for (ib = box->bmax; ib >= box->bmin; --ib) {
for (ir = box->rmin; ir <= box->rmax; ++ir) {
ig = box->gmin;
for (; ig <= box->gmax; ++ig) {
//count_iter ++;
if (FindColorCount(psHashHistogram,
MAKE_COLOR_CODE(ir, ig, ib)) != 0) {
//if( count_iter > 65536 ) printf("iter bmax=%d\n", count_iter);
box->bmax = ib;
goto have_bmax;
}
}
}
}
}
have_bmax:
;
}
/************************************************************************/
/* splitbox() */
/************************************************************************/
static void
splitbox(Colorbox* ptr, const int* histogram,
const HashHistogram* psHashHistogram,
int nCLevels,
Colorbox **pfreeboxes, Colorbox **pusedboxes,
GByte* pabyRedBand,
GByte* pabyGreenBand,
GByte* pabyBlueBand, int nPixels)
{
int hist2[256];
int first=0, last=0;
Colorbox *new_cb;
const int *iptr;
int *histp;
int i, j;
int ir,ig,ib;
int sum, sum1, sum2;
enum { RED, GREEN, BLUE } axis;
/*
* See which axis is the largest, do a histogram along that
* axis. Split at median point. Contract both new boxes to
* fit points and return
*/
i = ptr->rmax - ptr->rmin;
if (i >= ptr->gmax - ptr->gmin && i >= ptr->bmax - ptr->bmin)
axis = RED;
else if (ptr->gmax - ptr->gmin >= ptr->bmax - ptr->bmin)
axis = GREEN;
else
axis = BLUE;
/* get histogram along longest axis */
int nIters = (ptr->rmax - ptr->rmin + 1) * (ptr->gmax - ptr->gmin + 1) *
(ptr->bmax - ptr->bmin + 1);
//printf("nIters = %d\n", nIters);
switch (axis) {
case RED:
{
if( nPixels != 0 && nIters > nPixels )
{
memset(hist2, 0, sizeof(hist2));
const int rmin = ptr->rmin,
rmax = ptr->rmax,
gmin = ptr->gmin,
gmax = ptr->gmax,
bmin = ptr->bmin,
bmax = ptr->bmax;
for(int i=0;i<nPixels;i++)
{
int iR = pabyRedBand[i];
int iG = pabyGreenBand[i];
int iB = pabyBlueBand[i];
if( iR >= rmin && iR <= rmax &&
iG >= gmin && iG <= gmax &&
iB >= bmin && iB <= bmax )
{
hist2[iR] ++;
}
}
}
else if( psHashHistogram )
{
histp = &hist2[ptr->rmin];
for (ir = ptr->rmin; ir <= ptr->rmax; ++ir) {
*histp = 0;
for (ig = ptr->gmin; ig <= ptr->gmax; ++ig) {
for (ib = ptr->bmin; ib <= ptr->bmax; ++ib)
{
*histp += FindColorCount(psHashHistogram,
MAKE_COLOR_CODE(ir, ig, ib));
}
}
histp++;
}
}
else
{
histp = &hist2[ptr->rmin];
for (ir = ptr->rmin; ir <= ptr->rmax; ++ir) {
*histp = 0;
for (ig = ptr->gmin; ig <= ptr->gmax; ++ig) {
iptr = &HISTOGRAM(histogram,nCLevels,ir,ig,ptr->bmin);
for (ib = ptr->bmin; ib <= ptr->bmax; ++ib)
*histp += *iptr++;
}
histp++;
}
}
first = ptr->rmin;
last = ptr->rmax;
break;
}
case GREEN:
{
if( nPixels != 0 && nIters > nPixels )
{
memset(hist2, 0, sizeof(hist2));
const int rmin = ptr->rmin,
rmax = ptr->rmax,
gmin = ptr->gmin,
gmax = ptr->gmax,
bmin = ptr->bmin,
bmax = ptr->bmax;
for(int i=0;i<nPixels;i++)
{
int iR = pabyRedBand[i];
int iG = pabyGreenBand[i];
int iB = pabyBlueBand[i];
if( iR >= rmin && iR <= rmax &&
iG >= gmin && iG <= gmax &&
iB >= bmin && iB <= bmax )
{
hist2[iG] ++;
}
}
}
else if( psHashHistogram )
{
histp = &hist2[ptr->gmin];
for (ig = ptr->gmin; ig <= ptr->gmax; ++ig) {
*histp = 0;
for (ir = ptr->rmin; ir <= ptr->rmax; ++ir) {
for (ib = ptr->bmin; ib <= ptr->bmax; ++ib)
{
*histp += FindColorCount(psHashHistogram,
MAKE_COLOR_CODE(ir, ig, ib));
}
}
histp++;
}
}
else
{
histp = &hist2[ptr->gmin];
for (ig = ptr->gmin; ig <= ptr->gmax; ++ig) {
*histp = 0;
for (ir = ptr->rmin; ir <= ptr->rmax; ++ir) {
iptr = &HISTOGRAM(histogram,nCLevels,ir,ig,ptr->bmin);
for (ib = ptr->bmin; ib <= ptr->bmax; ++ib)
*histp += *iptr++;
}
histp++;
}
}
first = ptr->gmin;
last = ptr->gmax;
break;
}
case BLUE:
{
if( nPixels != 0 && nIters > nPixels )
{
memset(hist2, 0, sizeof(hist2));
const int rmin = ptr->rmin,
rmax = ptr->rmax,
gmin = ptr->gmin,
gmax = ptr->gmax,
bmin = ptr->bmin,
bmax = ptr->bmax;
for(int i=0;i<nPixels;i++)
{
int iR = pabyRedBand[i];
int iG = pabyGreenBand[i];
int iB = pabyBlueBand[i];
if( iR >= rmin && iR <= rmax &&
iG >= gmin && iG <= gmax &&
iB >= bmin && iB <= bmax )
{
hist2[iB] ++;
}
}
}
else if( psHashHistogram )
{
histp = &hist2[ptr->bmin];
for (ib = ptr->bmin; ib <= ptr->bmax; ++ib) {
*histp = 0;
for (ir = ptr->rmin; ir <= ptr->rmax; ++ir) {
for (ig = ptr->gmin; ig <= ptr->gmax; ++ig) {
*histp += FindColorCount(psHashHistogram,
MAKE_COLOR_CODE(ir, ig, ib));
}
}
histp++;
}
}
else
{
histp = &hist2[ptr->bmin];
for (ib = ptr->bmin; ib <= ptr->bmax; ++ib) {
*histp = 0;
for (ir = ptr->rmin; ir <= ptr->rmax; ++ir) {
iptr = &HISTOGRAM(histogram,nCLevels,ir,ptr->gmin,ib);
for (ig = ptr->gmin; ig <= ptr->gmax; ++ig) {
*histp += *iptr;
iptr += nCLevels;
}
}
histp++;
}
}
first = ptr->bmin;
last = ptr->bmax;
break;
}
}
/* find median point */
sum2 = ptr->total / 2;
histp = &hist2[first];
sum = 0;
for (i = first; i <= last && (sum += *histp++) < sum2; ++i)
;
if (i == first)
i++;
/* Create new box, re-allocate points */
new_cb = *pfreeboxes;
*pfreeboxes = new_cb->next;
if (*pfreeboxes)
(*pfreeboxes)->prev = NULL;
if (*pusedboxes)
(*pusedboxes)->prev = new_cb;
new_cb->next = *pusedboxes;
*pusedboxes = new_cb;
histp = &hist2[first];
for (sum1 = 0, j = first; j < i; j++)
sum1 += *histp++;
for (sum2 = 0, j = i; j <= last; j++)
sum2 += *histp++;
new_cb->total = sum1;
ptr->total = sum2;
new_cb->rmin = ptr->rmin;
new_cb->rmax = ptr->rmax;
new_cb->gmin = ptr->gmin;
new_cb->gmax = ptr->gmax;
new_cb->bmin = ptr->bmin;
new_cb->bmax = ptr->bmax;
switch (axis) {
case RED:
new_cb->rmax = i-1;
ptr->rmin = i;
break;
case GREEN:
new_cb->gmax = i-1;
ptr->gmin = i;
break;
case BLUE:
new_cb->bmax = i-1;
ptr->bmin = i;
break;
}
if( nPixels != 0 &&
(new_cb->rmax - new_cb->rmin + 1) * (new_cb->gmax - new_cb->gmin + 1) *
(new_cb->bmax - new_cb->bmin + 1) > nPixels )
{
shrinkboxFromBand(new_cb, pabyRedBand, pabyGreenBand, pabyBlueBand, nPixels);
}
else if( psHashHistogram != NULL )
{
shrinkboxFromHashHistogram(new_cb, psHashHistogram);
}
else
{
shrinkbox(new_cb, histogram, nCLevels);
}
if( nPixels != 0 &&
(ptr->rmax - ptr->rmin + 1) * (ptr->gmax - ptr->gmin + 1) *
(ptr->bmax - ptr->bmin + 1) > nPixels )
{
shrinkboxFromBand(ptr, pabyRedBand, pabyGreenBand, pabyBlueBand, nPixels);
}
else if( psHashHistogram != NULL )
{
shrinkboxFromHashHistogram(ptr, psHashHistogram);
}
else
{
shrinkbox(ptr, histogram, nCLevels);
}
}
/************************************************************************/
/* shrinkbox() */
/************************************************************************/
static void
shrinkbox(Colorbox* box, const int* histogram, int nCLevels)
{
const int *histp;
int ir, ig, ib;
//int count_iter;
if (box->rmax > box->rmin) {
//count_iter = 0;
for (ir = box->rmin; ir <= box->rmax; ++ir) {
for (ig = box->gmin; ig <= box->gmax; ++ig) {
histp = &HISTOGRAM(histogram, nCLevels, ir, ig, box->bmin);
for (ib = box->bmin; ib <= box->bmax; ++ib) {
//count_iter ++;
if (*histp++ != 0) {
//if( count_iter > 65536 ) printf("iter rmin=%d\n", count_iter);
box->rmin = ir;
goto have_rmin;
}
}
}
}
}
have_rmin:
if (box->rmax > box->rmin) {
//count_iter = 0;
for (ir = box->rmax; ir >= box->rmin; --ir) {
for (ig = box->gmin; ig <= box->gmax; ++ig) {
histp = &HISTOGRAM(histogram, nCLevels, ir, ig, box->bmin);
ib = box->bmin;
for (; ib <= box->bmax; ++ib) {
//count_iter ++;
if (*histp++ != 0) {
//if( count_iter > 65536 ) printf("iter rmax=%d\n", count_iter);
box->rmax = ir;
goto have_rmax;
}
}
}
}
}
have_rmax:
if (box->gmax > box->gmin) {
//count_iter = 0;
for (ig = box->gmin; ig <= box->gmax; ++ig) {
for (ir = box->rmin; ir <= box->rmax; ++ir) {
histp = &HISTOGRAM(histogram, nCLevels, ir, ig, box->bmin);
for (ib = box->bmin; ib <= box->bmax; ++ib) {
//count_iter ++;
if (*histp++ != 0) {
//if( count_iter > 65536 ) printf("iter gmin=%d\n", count_iter);
box->gmin = ig;
goto have_gmin;
}
}
}
}
}
have_gmin:
if (box->gmax > box->gmin) {
//count_iter = 0;
for (ig = box->gmax; ig >= box->gmin; --ig) {
for (ir = box->rmin; ir <= box->rmax; ++ir) {
histp = &HISTOGRAM(histogram, nCLevels, ir, ig, box->bmin);
ib = box->bmin;
for (; ib <= box->bmax; ++ib) {
//count_iter ++;
if (*histp++ != 0) {
//if( count_iter > 65536 ) printf("iter gmax=%d\n", count_iter);
box->gmax = ig;
goto have_gmax;
}
}
}
}
}
have_gmax:
if (box->bmax > box->bmin) {
//count_iter = 0;
for (ib = box->bmin; ib <= box->bmax; ++ib) {
for (ir = box->rmin; ir <= box->rmax; ++ir) {
histp = &HISTOGRAM(histogram, nCLevels, ir, box->gmin, ib);
for (ig = box->gmin; ig <= box->gmax; ++ig) {
//count_iter ++;
if (*histp != 0) {
//if( count_iter > 65536 ) printf("iter bmin=%d\n", count_iter);
box->bmin = ib;
goto have_bmin;
}
histp += nCLevels;
}
}
}
}
have_bmin:
if (box->bmax > box->bmin) {
//count_iter = 0;
for (ib = box->bmax; ib >= box->bmin; --ib) {
for (ir = box->rmin; ir <= box->rmax; ++ir) {
histp = &HISTOGRAM(histogram, nCLevels, ir, box->gmin, ib);
ig = box->gmin;
for (; ig <= box->gmax; ++ig) {
//count_iter ++;
if (*histp != 0) {
//if( count_iter > 65536 ) printf("iter bmax=%d\n", count_iter);
box->bmax = ib;
goto have_bmax;
}
histp += nCLevels;
}
}
}
}
have_bmax:
;
}