/******************************************************************************

* tif_overview.c,v 1.9 2005/05/25 09:03:16 dron Exp

*

* Project: TIFF Overview Builder

* Purpose: Library function for building overviews in a TIFF file.

* Author: Frank Warmerdam, warmerdam@pobox.com

*

* Notes:

* o Currently only images with bits_per_sample of a multiple of eight

* will work.

*

* o The downsampler currently just takes the top left pixel from the

* source rectangle. Eventually sampling options of averaging, mode, and

* ``center pixel'' should be offered.

*

* o The code will attempt to use the same kind of compression,

* photometric interpretation, and organization as the source image, but

* it doesn't copy geotiff tags to the reduced resolution images.

*

* o Reduced resolution overviews for multi-sample files will currently

* always be generated as PLANARCONFIG_SEPARATE. This could be fixed

* reasonable easily if needed to improve compatibility with other

* packages. Many don't properly support PLANARCONFIG_SEPARATE.

*

******************************************************************************

* Copyright (c) 1999, Frank Warmerdam

*

* 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.

******************************************************************************

*/

/* TODO: update notes in header above */

#include <stdio.h>

#include <assert.h>

#include <stdlib.h>

#include <string.h>

#include "tiffio.h"

#include "tif_ovrcache.h"

#ifndef FALSE

# define FALSE 0

# define TRUE 1

#endif

#ifndef MAX

# define MIN(a,b) ((a<b) ? a : b)

# define MAX(a,b) ((a>b) ? a : b)

#endif

void TIFFBuildOverviews( TIFF *, int, int *, int, const char *,

int (*)(double,void*), void * );

/************************************************************************/

/* TIFF_WriteOverview() */

/* */

/* Create a new directory, without any image data for an overview. */

/* Returns offset of newly created overview directory, but the */

/* current directory is reset to be the one in used when this */

/* function is called. */

/************************************************************************/

uint32 TIFF_WriteOverview( TIFF *hTIFF, uint32 nXSize, uint32 nYSize,

int nHorSubsampling, int nVerSubsampling )

{

toff_t nBaseDirOffset;

toff_t nOffset;

(void) bUseSubIFDs;

nBaseDirOffset = TIFFCurrentDirOffset( hTIFF );

TIFFCreateDirectory( hTIFF );

/* -------------------------------------------------------------------- */

/* Setup TIFF fields. */

/* -------------------------------------------------------------------- */

TIFFSetField( hTIFF, TIFFTAG_IMAGEWIDTH, nXSize );

TIFFSetField( hTIFF, TIFFTAG_IMAGELENGTH, nYSize );

if( nSamples == 1 )

TIFFSetField( hTIFF, TIFFTAG_PLANARCONFIG, PLANARCONFIG_CONTIG );

else

TIFFSetField( hTIFF, TIFFTAG_PLANARCONFIG, nPlanarConfig );

TIFFSetField( hTIFF, TIFFTAG_BITSPERSAMPLE, nBitsPerPixel );

TIFFSetField( hTIFF, TIFFTAG_SAMPLESPERPIXEL, nSamples );

TIFFSetField( hTIFF, TIFFTAG_COMPRESSION, nCompressFlag );

TIFFSetField( hTIFF, TIFFTAG_PHOTOMETRIC, nPhotometric );

TIFFSetField( hTIFF, TIFFTAG_SAMPLEFORMAT, nSampleFormat );

if( bTiled )

{

TIFFSetField( hTIFF, TIFFTAG_TILEWIDTH, nBlockXSize );

TIFFSetField( hTIFF, TIFFTAG_TILELENGTH, nBlockYSize );

}

else

TIFFSetField( hTIFF, TIFFTAG_ROWSPERSTRIP, nBlockYSize );

TIFFSetField( hTIFF, TIFFTAG_SUBFILETYPE, FILETYPE_REDUCEDIMAGE );

if( nPhotometric == PHOTOMETRIC_YCBCR || nPhotometric == PHOTOMETRIC_ITULAB )

{

TIFFSetField( hTIFF, TIFFTAG_YCBCRSUBSAMPLING, nHorSubsampling, nVerSubsampling);

/* TODO: also write YCbCrPositioning and YCbCrCoefficients tag identical to source IFD */

}

/* TODO: add command-line parameter for selecting jpeg compression quality

* that gets ignored when compression isn't jpeg */

/* -------------------------------------------------------------------- */

/* Write color table if one is present. */

/* -------------------------------------------------------------------- */

if( panRed != NULL )

{

TIFFSetField( hTIFF, TIFFTAG_COLORMAP, panRed, panGreen, panBlue );

}

/* -------------------------------------------------------------------- */

/* Write directory, and return byte offset. */

/* -------------------------------------------------------------------- */

if( TIFFWriteCheck( hTIFF, bTiled, "TIFFBuildOverviews" ) == 0 )

return 0;

TIFFWriteDirectory( hTIFF );

TIFFSetDirectory( hTIFF, (tdir_t) (TIFFNumberOfDirectories(hTIFF)-1) );

nOffset = TIFFCurrentDirOffset( hTIFF );

TIFFSetSubDirectory( hTIFF, nBaseDirOffset );

return nOffset;

}

/************************************************************************/

/* TIFF_GetSourceSamples() */

/************************************************************************/

static void

TIFF_GetSourceSamples( double * padfSamples, unsigned char *pabySrc,

int nPixelBytes, int nSampleFormat,

uint32 nXSize, uint32 nYSize,

int nPixelOffset, int nLineOffset )

{

uint32 iXOff, iYOff;

int iSample;

iSample = 0;

for( iYOff = 0; iYOff < nYSize; iYOff++ )

{

for( iXOff = 0; iXOff < nXSize; iXOff++ )

{

unsigned char *pabyData;

pabyData = pabySrc + iYOff * nLineOffset + iXOff * nPixelOffset;

if( nSampleFormat == SAMPLEFORMAT_UINT && nPixelBytes == 1 )

{

padfSamples[iSample++] = *pabyData;

}

else if( nSampleFormat == SAMPLEFORMAT_UINT && nPixelBytes == 2 )

{

padfSamples[iSample++] = ((uint16 *) pabyData)[0];

}

else if( nSampleFormat == SAMPLEFORMAT_UINT && nPixelBytes == 4 )

{

padfSamples[iSample++] = ((uint32 *) pabyData)[0];

}

else if( nSampleFormat == SAMPLEFORMAT_INT && nPixelBytes == 2 )

{

padfSamples[iSample++] = ((int16 *) pabyData)[0];

}

else if( nSampleFormat == SAMPLEFORMAT_INT && nPixelBytes == 32 )

{

padfSamples[iSample++] = ((int32 *) pabyData)[0];

}

else if( nSampleFormat == SAMPLEFORMAT_IEEEFP && nPixelBytes == 4 )

{

padfSamples[iSample++] = ((float *) pabyData)[0];

}

else if( nSampleFormat == SAMPLEFORMAT_IEEEFP && nPixelBytes == 8 )

{

padfSamples[iSample++] = ((double *) pabyData)[0];

}

}

}

}

/************************************************************************/

/* TIFF_SetSample() */

/************************************************************************/

static void

TIFF_SetSample( unsigned char * pabyData, int nPixelBytes, int nSampleFormat,

double dfValue )

{

if( nSampleFormat == SAMPLEFORMAT_UINT && nPixelBytes == 1 )

{

*pabyData = (unsigned char) MAX(0,MIN(255,dfValue));

}

else if( nSampleFormat == SAMPLEFORMAT_UINT && nPixelBytes == 2 )

{

*((uint16 *)pabyData) = (uint16) MAX(0,MIN(65535,dfValue));

}

else if( nSampleFormat == SAMPLEFORMAT_UINT && nPixelBytes == 4 )

{

*((uint32 *)pabyData) = (uint32) dfValue;

}

else if( nSampleFormat == SAMPLEFORMAT_INT && nPixelBytes == 2 )

{

*((int16 *)pabyData) = (int16) MAX(-32768,MIN(32767,dfValue));

}

else if( nSampleFormat == SAMPLEFORMAT_INT && nPixelBytes == 32 )

{

*((int32 *)pabyData) = (int32) dfValue;

}

else if( nSampleFormat == SAMPLEFORMAT_IEEEFP && nPixelBytes == 4 )

{

*((float *)pabyData) = (float) dfValue;

}

else if( nSampleFormat == SAMPLEFORMAT_IEEEFP && nPixelBytes == 8 )

{

*((double *)pabyData) = dfValue;

}

}

/************************************************************************/

/* TIFF_DownSample() */

/* */

/* Down sample a tile of full res data into a window of a tile */

/* of downsampled data. */

/************************************************************************/

static

void TIFF_DownSample( unsigned char *pabySrcTile,

int nSampleFormat, const char * pszResampling )

{

uint32 i, j;

int k, nPixelBytes = (nBitsPerPixel) / 8;

int nPixelGroupBytes = (nBitsPerPixel+nPixelSkewBits)/8;

unsigned char *pabySrc, *pabyDst;

double *padfSamples;

assert( nBitsPerPixel >= 8 );

padfSamples = (double *) malloc(sizeof(double) * nOMult * nOMult);

/* ==================================================================== */

/* Loop over scanline chunks to process, establishing where the */

/* data is going. */

/* ==================================================================== */

for( j = 0; j*nOMult < nBlockYSize; j++ )

{

if( j + nTYOff >= nOBlockYSize )

break;

pabyDst = pabyOTile + ((j+nTYOff)*nOBlockXSize + nTXOff)

* nPixelBytes * nPixelGroupBytes;

/* -------------------------------------------------------------------- */

/* Handler nearest resampling ... we don't even care about the */

/* data type, we just do a bytewise copy. */

/* -------------------------------------------------------------------- */

if( strncmp(pszResampling,"nearest",4) == 0

|| strncmp(pszResampling,"NEAR",4) == 0 )

{

pabySrc = pabySrcTile + j*nOMult*nBlockXSize * nPixelGroupBytes;

for( i = 0; i*nOMult < nBlockXSize; i++ )

{

if( i + nTXOff >= nOBlockXSize )

break;

/*

* For now use simple subsampling, from the top left corner

* of the source block of pixels.

*/

for( k = 0; k < nPixelBytes; k++ )

pabyDst[k] = pabySrc[k];

pabyDst += nPixelBytes * nPixelGroupBytes;

pabySrc += nOMult * nPixelGroupBytes;

}

}

/* -------------------------------------------------------------------- */

/* Handle the case of averaging. For this we also have to */

/* handle each sample format we are concerned with. */

/* -------------------------------------------------------------------- */

else if( strncmp(pszResampling,"averag",6) == 0

|| strncmp(pszResampling,"AVERAG",6) == 0 )

{

pabySrc = pabySrcTile + j*nOMult*nBlockXSize * nPixelGroupBytes;

for( i = 0; i*nOMult < nBlockXSize; i++ )

{

double dfTotal;

uint32 nXSize, nYSize, iSample;

if( i + nTXOff >= nOBlockXSize )

break;

nXSize = MIN((uint32)nOMult,nBlockXSize-i);

nYSize = MIN((uint32)nOMult,nBlockYSize-j);

TIFF_GetSourceSamples( padfSamples, pabySrc,

nPixelBytes, nSampleFormat,

nXSize, nYSize,

nPixelGroupBytes,

nPixelGroupBytes * nBlockXSize );

dfTotal = 0;

for( iSample = 0; iSample < nXSize*nYSize; iSample++ )

{

dfTotal += padfSamples[iSample];

}

TIFF_SetSample( pabyDst, nPixelBytes, nSampleFormat,

dfTotal / (nXSize*nYSize) );

pabySrc += nOMult * nPixelGroupBytes;

pabyDst += nPixelBytes;

}

}

}

free( padfSamples );

}

/************************************************************************/

/* TIFF_DownSample_Subsampled() */

/************************************************************************/

static

void TIFF_DownSample_Subsampled( unsigned char *pabySrcTile, int nSample,

int nHorSubsampling, int nVerSubsampling )

{

/* TODO: test with variety of subsampling values, and incovinient tile/strip sizes */

int nSampleBlockSize;

int nSourceSampleRowSize;

int nDestSampleRowSize;

uint32 nSourceX, nSourceY;

uint32 nSourceXSec, nSourceYSec;

uint32 nSourceXSecEnd, nSourceYSecEnd;

uint32 nDestX, nDestY;

int nSampleOffsetInSampleBlock;

unsigned int nCummulator;

unsigned int nCummulatorCount;

nSampleBlockSize = nHorSubsampling * nVerSubsampling + 2;

nSourceSampleRowSize =

( ( nBlockXSize + nHorSubsampling - 1 ) / nHorSubsampling ) * nSampleBlockSize;

nDestSampleRowSize =

( ( nOBlockXSize + nHorSubsampling - 1 ) / nHorSubsampling ) * nSampleBlockSize;

if( strncmp(pszResampling,"nearest",4) == 0

|| strncmp(pszResampling,"NEAR",4) == 0 )

{

if( nSample == 0 )

{

for( nSourceY = 0, nDestY = nTYOff;

nSourceY < nBlockYSize;

nSourceY += nOMult, nDestY ++)

{

if( nDestY >= nOBlockYSize )

break;

for( nSourceX = 0, nDestX = nTXOff;

nSourceX < nBlockXSize;

nSourceX += nOMult, nDestX ++)

{

if( nDestX >= nOBlockXSize )

break;

* ( pabyOTile + ( nDestY / nVerSubsampling ) * nDestSampleRowSize

+ ( nDestY % nVerSubsampling ) * nHorSubsampling

+ ( nDestX / nHorSubsampling ) * nSampleBlockSize

+ ( nDestX % nHorSubsampling ) ) =

* ( pabySrcTile + ( nSourceY / nVerSubsampling ) * nSourceSampleRowSize

+ ( nSourceY % nVerSubsampling ) * nHorSubsampling

+ ( nSourceX / nHorSubsampling ) * nSampleBlockSize

+ ( nSourceX % nHorSubsampling ) );

}

}

}

else

{

nSampleOffsetInSampleBlock = nHorSubsampling * nVerSubsampling + nSample - 1;

for( nSourceY = 0, nDestY = ( nTYOff / nVerSubsampling );

nSourceY < ( nBlockYSize / nVerSubsampling );

nSourceY += nOMult, nDestY ++)

{

if( nDestY*nVerSubsampling >= nOBlockYSize )

break;

for( nSourceX = 0, nDestX = ( nTXOff / nHorSubsampling );

nSourceX < ( nBlockXSize / nHorSubsampling );

nSourceX += nOMult, nDestX ++)

{

if( nDestX*nHorSubsampling >= nOBlockXSize )

break;

* ( pabyOTile + nDestY * nDestSampleRowSize

+ nDestX * nSampleBlockSize

+ nSampleOffsetInSampleBlock ) =

* ( pabySrcTile + nSourceY * nSourceSampleRowSize

+ nSourceX * nSampleBlockSize

+ nSampleOffsetInSampleBlock );

}

}

}

}

else if( strncmp(pszResampling,"averag",6) == 0

|| strncmp(pszResampling,"AVERAG",6) == 0 )

{

if( nSample == 0 )

{

for( nSourceY = 0, nDestY = nTYOff; nSourceY < nBlockYSize; nSourceY += nOMult, nDestY ++)

{

if( nDestY >= nOBlockYSize )

break;

for( nSourceX = 0, nDestX = nTXOff; nSourceX < nBlockXSize; nSourceX += nOMult, nDestX ++)

{

if( nDestX >= nOBlockXSize )

break;

nSourceXSecEnd = nSourceX + nOMult;

if( nSourceXSecEnd > nBlockXSize )

nSourceXSecEnd = nBlockXSize;

nSourceYSecEnd = nSourceY + nOMult;

if( nSourceYSecEnd > nBlockYSize )

nSourceYSecEnd = nBlockYSize;

nCummulator = 0;

for( nSourceYSec = nSourceY; nSourceYSec < nSourceYSecEnd; nSourceYSec ++)

{

for( nSourceXSec = nSourceX; nSourceXSec < nSourceXSecEnd; nSourceXSec ++)

{

nCummulator += * ( pabySrcTile + ( nSourceYSec / nVerSubsampling ) * nSourceSampleRowSize

+ ( nSourceYSec % nVerSubsampling ) * nHorSubsampling

+ ( nSourceXSec / nHorSubsampling ) * nSampleBlockSize

+ ( nSourceXSec % nHorSubsampling ) );

}

}

nCummulatorCount = ( nSourceXSecEnd - nSourceX ) * ( nSourceYSecEnd - nSourceY );

* ( pabyOTile + ( nDestY / nVerSubsampling ) * nDestSampleRowSize

+ ( nDestY % nVerSubsampling ) * nHorSubsampling

+ ( nDestX / nHorSubsampling ) * nSampleBlockSize

+ ( nDestX % nHorSubsampling ) ) =

( ( nCummulator + ( nCummulatorCount >> 1 ) ) / nCummulatorCount );

}

}

}

else

{

nSampleOffsetInSampleBlock = nHorSubsampling * nVerSubsampling + nSample - 1;

for( nSourceY = 0, nDestY = ( nTYOff / nVerSubsampling ); nSourceY < ( nBlockYSize / nVerSubsampling );

nSourceY += nOMult, nDestY ++)

{

if( nDestY*nVerSubsampling >= nOBlockYSize )

break;

for( nSourceX = 0, nDestX = ( nTXOff / nHorSubsampling ); nSourceX < ( nBlockXSize / nHorSubsampling );

nSourceX += nOMult, nDestX ++)

{

if( nDestX*nHorSubsampling >= nOBlockXSize )

break;

nSourceXSecEnd = nSourceX + nOMult;

if( nSourceXSecEnd > ( nBlockXSize / nHorSubsampling ) )

nSourceXSecEnd = ( nBlockXSize / nHorSubsampling );

nSourceYSecEnd = nSourceY + nOMult;

if( nSourceYSecEnd > ( nBlockYSize / nVerSubsampling ) )

nSourceYSecEnd = ( nBlockYSize / nVerSubsampling );

nCummulator = 0;

for( nSourceYSec = nSourceY; nSourceYSec < nSourceYSecEnd; nSourceYSec ++)

{

for( nSourceXSec = nSourceX; nSourceXSec < nSourceXSecEnd; nSourceXSec ++)

{

nCummulator += * ( pabySrcTile + nSourceYSec * nSourceSampleRowSize

+ nSourceXSec * nSampleBlockSize

+ nSampleOffsetInSampleBlock );

}

}

nCummulatorCount = ( nSourceXSecEnd - nSourceX ) * ( nSourceYSecEnd - nSourceY );

* ( pabyOTile + nDestY * nDestSampleRowSize

+ nDestX * nSampleBlockSize

+ nSampleOffsetInSampleBlock ) =

( ( nCummulator + ( nCummulatorCount >> 1 ) ) / nCummulatorCount );

}

}

}

}

}

/************************************************************************/

/* TIFF_ProcessFullResBlock() */

/* */

/* Process one block of full res data, downsampling into each */

/* of the overviews. */

/************************************************************************/

void TIFF_ProcessFullResBlock( TIFF *hTIFF, int nPlanarConfig,

int nSampleFormat, const char * pszResampling )

{

int iOverview, iSample;

for( iSample = 0; iSample < nSamples; iSample++ )

{

/*

* We have to read a tile/strip for each sample for

* PLANARCONFIG_SEPARATE. Otherwise, we just read all the samples

* at once when handling the first sample.

*/

if( nPlanarConfig == PLANARCONFIG_SEPARATE || iSample == 0 )

{

if( TIFFIsTiled(hTIFF) )

{

TIFFReadEncodedTile( hTIFF,

TIFFComputeTile(hTIFF, nSXOff, nSYOff,

0, (tsample_t)iSample ),

pabySrcTile,

TIFFTileSize(hTIFF));

}

else

{

TIFFReadEncodedStrip( hTIFF,

TIFFComputeStrip(hTIFF, nSYOff,

(tsample_t) iSample),

pabySrcTile,

TIFFStripSize(hTIFF) );

}

}

/*

* Loop over destination overview layers

*/

for( iOverview = 0; iOverview < nOverviews; iOverview++ )

{

TIFFOvrCache *poRBI = papoRawBIs[iOverview];

unsigned char *pabyOTile;

uint32 nTXOff, nTYOff, nOXOff, nOYOff, nOMult;

uint32 nOBlockXSize = poRBI->nBlockXSize;

uint32 nOBlockYSize = poRBI->nBlockYSize;

int nSkewBits, nSampleByteOffset;

/*

* Fetch the destination overview tile

*/

nOMult = panOvList[iOverview];

nOXOff = (nSXOff/nOMult) / nOBlockXSize;

nOYOff = (nSYOff/nOMult) / nOBlockYSize;

if( bSubsampled )

{

pabyOTile = TIFFGetOvrBlock_Subsampled( poRBI, nOXOff, nOYOff );

/*

* Establish the offset into this tile at which we should

* start placing data.

*/

nTXOff = (nSXOff - nOXOff*nOMult*nOBlockXSize) / nOMult;

nTYOff = (nSYOff - nOYOff*nOMult*nOBlockYSize) / nOMult;

#ifdef DBMALLOC

malloc_chain_check( 1 );

#endif

TIFF_DownSample_Subsampled( pabySrcTile, iSample,

nBlockXSize, nBlockYSize,

pabyOTile,

poRBI->nBlockXSize, poRBI->nBlockYSize,

nTXOff, nTYOff,

nOMult, pszResampling,

nHorSubsampling, nVerSubsampling );

#ifdef DBMALLOC

malloc_chain_check( 1 );

#endif

}

else

{

pabyOTile = TIFFGetOvrBlock( poRBI, nOXOff, nOYOff, iSample );

/*

* Establish the offset into this tile at which we should

* start placing data.

*/

nTXOff = (nSXOff - nOXOff*nOMult*nOBlockXSize) / nOMult;

nTYOff = (nSYOff - nOYOff*nOMult*nOBlockYSize) / nOMult;

/*

* Figure out the skew (extra space between ``our samples'') and

* the byte offset to the first sample.

*/

assert( (nBitsPerPixel % 8) == 0 );

if( nPlanarConfig == PLANARCONFIG_SEPARATE )

{

nSkewBits = 0;

nSampleByteOffset = 0;

}

else

{

nSkewBits = nBitsPerPixel * (nSamples-1);

nSampleByteOffset = (nBitsPerPixel/8) * iSample;

}

/*

* Perform the downsampling.

*/

#ifdef DBMALLOC

malloc_chain_check( 1 );

#endif

TIFF_DownSample( pabySrcTile + nSampleByteOffset,

nBlockXSize, nBlockYSize,

nSkewBits, nBitsPerPixel, pabyOTile,

poRBI->nBlockXSize, poRBI->nBlockYSize,

nTXOff, nTYOff,

nOMult, nSampleFormat, pszResampling );

#ifdef DBMALLOC

malloc_chain_check( 1 );

#endif

}

}

}

}

/************************************************************************/

/* TIFF_BuildOverviews() */

/* */

/* Build the requested list of overviews. Overviews are */

/* maintained in a bunch of temporary files and then these are */

/* written back to the TIFF file. Only one pass through the */

/* source TIFF file is made for any number of output */

/* overviews. */

/************************************************************************/

void TIFFBuildOverviews( TIFF *hTIFF, int nOverviews, int * panOvList,

int bUseSubIFDs, const char *pszResampleMethod,

int (*pfnProgress)( double, void * ),

void * pProgressData )

{

TIFFOvrCache **papoRawBIs;

uint32 nXSize, nYSize, nBlockXSize, nBlockYSize;

uint16 nBitsPerPixel, nPhotometric, nCompressFlag, nSamples,

nPlanarConfig, nSampleFormat;

int bSubsampled;

uint16 nHorSubsampling, nVerSubsampling;

int bTiled, nSXOff, nSYOff, i;

unsigned char *pabySrcTile;

uint16 *panRedMap, *panGreenMap, *panBlueMap;

TIFFErrorHandler pfnWarning;

(void) pfnProgress;

(void) pProgressData;

/* -------------------------------------------------------------------- */

/* Get the base raster size. */

/* -------------------------------------------------------------------- */

TIFFGetField( hTIFF, TIFFTAG_IMAGEWIDTH, &nXSize );

TIFFGetField( hTIFF, TIFFTAG_IMAGELENGTH, &nYSize );

TIFFGetField( hTIFF, TIFFTAG_BITSPERSAMPLE, &nBitsPerPixel );

/* TODO: nBitsPerPixel seems misnomer and may need renaming to nBitsPerSample */

TIFFGetField( hTIFF, TIFFTAG_SAMPLESPERPIXEL, &nSamples );

TIFFGetFieldDefaulted( hTIFF, TIFFTAG_PLANARCONFIG, &nPlanarConfig );

TIFFGetFieldDefaulted( hTIFF, TIFFTAG_PHOTOMETRIC, &nPhotometric );

TIFFGetFieldDefaulted( hTIFF, TIFFTAG_COMPRESSION, &nCompressFlag );

TIFFGetFieldDefaulted( hTIFF, TIFFTAG_SAMPLEFORMAT, &nSampleFormat );

if( nPhotometric == PHOTOMETRIC_YCBCR || nPhotometric == PHOTOMETRIC_ITULAB )

{

if( nBitsPerPixel != 8 || nSamples != 3 || nPlanarConfig != PLANARCONFIG_CONTIG ||

nSampleFormat != SAMPLEFORMAT_UINT)

{

/* TODO: use of TIFFError is inconsistent with use of fprintf in addtiffo.c, sort out */

TIFFErrorExt( TIFFClientdata(hTIFF), "TIFFBuildOverviews",

"File `%s' has an unsupported subsampling configuration.\n",

TIFFFileName(hTIFF) );

/* If you need support for this particular flavor, please contact either

* Frank Warmerdam warmerdam@pobox.com

* Joris Van Damme info@awaresystems.be

*/

return;

}

bSubsampled = 1;

TIFFGetField( hTIFF, TIFFTAG_YCBCRSUBSAMPLING, &nHorSubsampling, &nVerSubsampling );

/* TODO: find out if maybe TIFFGetFieldDefaulted is better choice for YCbCrSubsampling tag */

}

else

{

if( nBitsPerPixel < 8 )

{

/* TODO: use of TIFFError is inconsistent with use of fprintf in addtiffo.c, sort out */

TIFFErrorExt( TIFFClientdata(hTIFF), "TIFFBuildOverviews",

"File `%s' has samples of %d bits per sample. Sample\n"

"sizes of less than 8 bits per sample are not supported.\n",

TIFFFileName(hTIFF), nBitsPerPixel );

return;

}

bSubsampled = 0;

nHorSubsampling = 1;

nVerSubsampling = 1;

}

/* -------------------------------------------------------------------- */

/* Turn off warnings to avoid alot of repeated warnings while */

/* rereading directories. */

/* -------------------------------------------------------------------- */

pfnWarning = TIFFSetWarningHandler( NULL );

/* -------------------------------------------------------------------- */

/* Get the base raster block size. */

/* -------------------------------------------------------------------- */

if( TIFFGetField( hTIFF, TIFFTAG_ROWSPERSTRIP, &(nBlockYSize) ) )

{

nBlockXSize = nXSize;

bTiled = FALSE;

}

else

{

TIFFGetField( hTIFF, TIFFTAG_TILEWIDTH, &nBlockXSize );

TIFFGetField( hTIFF, TIFFTAG_TILELENGTH, &nBlockYSize );

bTiled = TRUE;

}

/* -------------------------------------------------------------------- */

/* Capture the pallette if there is one. */

/* -------------------------------------------------------------------- */

if( TIFFGetField( hTIFF, TIFFTAG_COLORMAP,

&panRedMap, &panGreenMap, &panBlueMap ) )

{

uint16 *panRed2, *panGreen2, *panBlue2;

int nColorCount = 1 << nBitsPerPixel;

panRed2 = (uint16 *) _TIFFmalloc(2*nColorCount);

panGreen2 = (uint16 *) _TIFFmalloc(2*nColorCount);

panBlue2 = (uint16 *) _TIFFmalloc(2*nColorCount);

memcpy( panRed2, panRedMap, 2 * nColorCount );

memcpy( panGreen2, panGreenMap, 2 * nColorCount );

memcpy( panBlue2, panBlueMap, 2 * nColorCount );

panRedMap = panRed2;

panGreenMap = panGreen2;

panBlueMap = panBlue2;

}

else

{

panRedMap = panGreenMap = panBlueMap = NULL;

}

/* -------------------------------------------------------------------- */

/* Initialize overviews. */

/* -------------------------------------------------------------------- */

papoRawBIs = (TIFFOvrCache **) _TIFFmalloc(nOverviews*sizeof(void*));

for( i = 0; i < nOverviews; i++ )

{

uint32 nOXSize, nOYSize, nOBlockXSize, nOBlockYSize;

toff_t nDirOffset;

nOXSize = (nXSize + panOvList[i] - 1) / panOvList[i];

nOYSize = (nYSize + panOvList[i] - 1) / panOvList[i];

nOBlockXSize = MIN(nBlockXSize,nOXSize);

nOBlockYSize = MIN(nBlockYSize,nOYSize);

if( bTiled )

{

if( (nOBlockXSize % 16) != 0 )

nOBlockXSize = nOBlockXSize + 16 - (nOBlockXSize % 16);

if( (nOBlockYSize % 16) != 0 )

nOBlockYSize = nOBlockYSize + 16 - (nOBlockYSize % 16);

}

nDirOffset = TIFF_WriteOverview( hTIFF, nOXSize, nOYSize,

nBitsPerPixel, nPlanarConfig,

nSamples, nOBlockXSize, nOBlockYSize,

bTiled, nCompressFlag, nPhotometric,

nSampleFormat,

panRedMap, panGreenMap, panBlueMap,

bUseSubIFDs,

nHorSubsampling, nVerSubsampling );

papoRawBIs[i] = TIFFCreateOvrCache( hTIFF, nDirOffset );

}

if( panRedMap != NULL )

{

_TIFFfree( panRedMap );

_TIFFfree( panGreenMap );

_TIFFfree( panBlueMap );

}

/* -------------------------------------------------------------------- */

/* Allocate a buffer to hold a source block. */

/* -------------------------------------------------------------------- */

if( bTiled )

pabySrcTile = (unsigned char *) _TIFFmalloc(TIFFTileSize(hTIFF));

else

pabySrcTile = (unsigned char *) _TIFFmalloc(TIFFStripSize(hTIFF));

/* -------------------------------------------------------------------- */

/* Loop over the source raster, applying data to the */

/* destination raster. */

/* -------------------------------------------------------------------- */

for( nSYOff = 0; nSYOff < (int) nYSize; nSYOff += nBlockYSize )

{

for( nSXOff = 0; nSXOff < (int) nXSize; nSXOff += nBlockXSize )

{

/*

* Read and resample into the various overview images.

*/

TIFF_ProcessFullResBlock( hTIFF, nPlanarConfig,

bSubsampled,nHorSubsampling,nVerSubsampling,

nOverviews, panOvList,

nBitsPerPixel, nSamples, papoRawBIs,

nSXOff, nSYOff, pabySrcTile,

nBlockXSize, nBlockYSize,

nSampleFormat, pszResampleMethod );

}

}

_TIFFfree( pabySrcTile );

/* -------------------------------------------------------------------- */

/* Cleanup the rawblockedimage files. */

/* -------------------------------------------------------------------- */

for( i = 0; i < nOverviews; i++ )

{

TIFFDestroyOvrCache( papoRawBIs[i] );

}

if( papoRawBIs != NULL )

_TIFFfree( papoRawBIs );

TIFFSetWarningHandler( pfnWarning );

}

/*

* Local Variables:

* mode: c

* c-basic-offset: 8

* fill-column: 78

* End:

*/