404 lines
13 KiB
C++
404 lines
13 KiB
C++
|
/* -----------------------------------------------------------------------------
|
||
|
|
|
||
|
|
Copyright (c) 2006 Simon Brown si@sjbrown.co.uk
|
||
|
|
|
||
|
|
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.
|
||
|
|
|
||
|
|
-------------------------------------------------------------------------- */
|
||
|
|
|
||
|
|
#include <string.h>
|
||
|
|
#include "squish.h"
|
||
|
|
#include "colourset.h"
|
||
|
|
#include "maths.h"
|
||
|
|
#include "rangefit.h"
|
||
|
|
#include "clusterfit.h"
|
||
|
|
#include "colourblock.h"
|
||
|
|
#include "alpha.h"
|
||
|
|
#include "singlecolourfit.h"
|
||
|
|
|
||
|
|
namespace squish {
|
||
|
|
|
||
|
|
static int FixFlags( int flags )
|
||
|
|
{
|
||
|
|
// grab the flag bits
|
||
|
|
int method = flags & ( kDxt1 | kDxt3 | kDxt5 | kBc4 | kBc5 );
|
||
|
|
int fit = flags & ( kColourIterativeClusterFit | kColourClusterFit | kColourRangeFit );
|
||
|
|
int extra = flags & (kWeightColourByAlpha | kToLinear);
|
||
|
|
|
||
|
|
// set defaults
|
||
|
|
if ( method != kDxt3
|
||
|
|
&& method != kDxt5
|
||
|
|
&& method != kBc4
|
||
|
|
&& method != kBc5 )
|
||
|
|
{
|
||
|
|
method = kDxt1;
|
||
|
|
}
|
||
|
|
if( fit != kColourRangeFit && fit != kColourIterativeClusterFit )
|
||
|
|
fit = kColourClusterFit;
|
||
|
|
|
||
|
|
// done
|
||
|
|
return method | fit | extra;
|
||
|
|
}
|
||
|
|
|
||
|
|
void CompressMasked( u8 const* rgba, int mask, void* block, int flags, float* metric )
|
||
|
|
{
|
||
|
|
// fix any bad flags
|
||
|
|
flags = FixFlags( flags );
|
||
|
|
|
||
|
|
if ( ( flags & ( kBc4 | kBc5 ) ) != 0 )
|
||
|
|
{
|
||
|
|
u8 alpha[16*4];
|
||
|
|
for( int i = 0; i < 16; ++i )
|
||
|
|
{
|
||
|
|
alpha[i*4 + 3] = rgba[i*4 + 0]; // copy R to A
|
||
|
|
}
|
||
|
|
|
||
|
|
u8* rBlock = reinterpret_cast< u8* >( block );
|
||
|
|
CompressAlphaDxt5( alpha, mask, rBlock );
|
||
|
|
|
||
|
|
if ( ( flags & ( kBc5 ) ) != 0 )
|
||
|
|
{
|
||
|
|
for( int i = 0; i < 16; ++i )
|
||
|
|
{
|
||
|
|
alpha[i*4 + 3] = rgba[i*4 + 1]; // copy G to A
|
||
|
|
}
|
||
|
|
|
||
|
|
u8* gBlock = reinterpret_cast< u8* >( block ) + 8;
|
||
|
|
CompressAlphaDxt5( alpha, mask, gBlock );
|
||
|
|
}
|
||
|
|
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
|
||
|
|
// get the block locations
|
||
|
|
void* colourBlock = block;
|
||
|
|
void* alphaBlock = block;
|
||
|
|
if( ( flags & ( kDxt3 | kDxt5 ) ) != 0 )
|
||
|
|
colourBlock = reinterpret_cast< u8* >( block ) + 8;
|
||
|
|
|
||
|
|
// create the minimal point set
|
||
|
|
ColourSet colours( rgba, mask, flags );
|
||
|
|
|
||
|
|
// check the compression type and compress colour
|
||
|
|
if( colours.GetCount() == 1 )
|
||
|
|
{
|
||
|
|
// always do a single colour fit
|
||
|
|
SingleColourFit fit( &colours, flags );
|
||
|
|
fit.Compress( colourBlock );
|
||
|
|
}
|
||
|
|
else if( ( flags & kColourRangeFit ) != 0 || colours.GetCount() == 0 )
|
||
|
|
{
|
||
|
|
// do a range fit
|
||
|
|
RangeFit fit( &colours, flags, metric );
|
||
|
|
fit.Compress( colourBlock );
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
// default to a cluster fit (could be iterative or not)
|
||
|
|
ClusterFit fit( &colours, flags, metric );
|
||
|
|
fit.Compress( colourBlock );
|
||
|
|
}
|
||
|
|
|
||
|
|
// compress alpha separately if necessary
|
||
|
|
if( ( flags & kDxt3 ) != 0 )
|
||
|
|
CompressAlphaDxt3( rgba, mask, alphaBlock );
|
||
|
|
else if( ( flags & kDxt5 ) != 0 )
|
||
|
|
CompressAlphaDxt5( rgba, mask, alphaBlock );
|
||
|
|
}
|
||
|
|
|
||
|
|
void Decompress( u8* rgba, void const* block, int flags )
|
||
|
|
{
|
||
|
|
// fix any bad flags
|
||
|
|
flags = FixFlags( flags );
|
||
|
|
|
||
|
|
// get the block locations
|
||
|
|
void const* colourBlock = block;
|
||
|
|
void const* alphaBlock = block;
|
||
|
|
if( ( flags & ( kDxt3 | kDxt5 ) ) != 0 )
|
||
|
|
colourBlock = reinterpret_cast< u8 const* >( block ) + 8;
|
||
|
|
|
||
|
|
// decompress colour
|
||
|
|
DecompressColour( rgba, colourBlock, ( flags & kDxt1 ) != 0 );
|
||
|
|
|
||
|
|
// decompress alpha separately if necessary
|
||
|
|
if( ( flags & kDxt3 ) != 0 )
|
||
|
|
DecompressAlphaDxt3( rgba, alphaBlock );
|
||
|
|
else if( ( flags & kDxt5 ) != 0 )
|
||
|
|
DecompressAlphaDxt5( rgba, alphaBlock );
|
||
|
|
}
|
||
|
|
|
||
|
|
int GetStorageRequirements( int width, int height, int flags )
|
||
|
|
{
|
||
|
|
// fix any bad flags
|
||
|
|
flags = FixFlags( flags );
|
||
|
|
|
||
|
|
// compute the storage requirements
|
||
|
|
int blockcount = ( ( width + 3 )/4 ) * ( ( height + 3 )/4 );
|
||
|
|
int blocksize = ( ( flags & ( kDxt1 | kBc4 ) ) != 0 ) ? 8 : 16;
|
||
|
|
return blockcount*blocksize;
|
||
|
|
}
|
||
|
|
|
||
|
|
void CopyRGBA( u8 const* source, u8* dest, int flags )
|
||
|
|
{
|
||
|
|
if (flags & kSourceBGRA)
|
||
|
|
{
|
||
|
|
// convert from bgra to rgba
|
||
|
|
dest[0] = source[2];
|
||
|
|
dest[1] = source[1];
|
||
|
|
dest[2] = source[0];
|
||
|
|
dest[3] = source[3];
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
for( int i = 0; i < 4; ++i )
|
||
|
|
*dest++ = *source++;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void CompressImage( u8 const* rgba, int width, int height, int pitch, void* blocks, int flags, float* metric )
|
||
|
|
{
|
||
|
|
// fix any bad flags
|
||
|
|
flags = FixFlags( flags );
|
||
|
|
|
||
|
|
// loop over blocks
|
||
|
|
#ifdef SQUISH_USE_OPENMP
|
||
|
|
# pragma omp parallel for
|
||
|
|
#endif
|
||
|
|
for( int y = 0; y < height; y += 4 )
|
||
|
|
{
|
||
|
|
// initialise the block output
|
||
|
|
u8* targetBlock = reinterpret_cast< u8* >( blocks );
|
||
|
|
int bytesPerBlock = ( ( flags & ( kDxt1 | kBc4 ) ) != 0 ) ? 8 : 16;
|
||
|
|
targetBlock += ( (y / 4) * ( (width + 3) / 4) ) * bytesPerBlock;
|
||
|
|
|
||
|
|
for( int x = 0; x < width; x += 4 )
|
||
|
|
{
|
||
|
|
// build the 4x4 block of pixels
|
||
|
|
u8 sourceRgba[16*4];
|
||
|
|
u8* targetPixel = sourceRgba;
|
||
|
|
int mask = 0;
|
||
|
|
for( int py = 0; py < 4; ++py )
|
||
|
|
{
|
||
|
|
for( int px = 0; px < 4; ++px )
|
||
|
|
{
|
||
|
|
// get the source pixel in the image
|
||
|
|
int sx = x + px;
|
||
|
|
int sy = y + py;
|
||
|
|
|
||
|
|
// enable if we're in the image
|
||
|
|
if( sx < width && sy < height )
|
||
|
|
{
|
||
|
|
// copy the rgba value
|
||
|
|
u8 const* sourcePixel = rgba + pitch*sy + 4*sx;
|
||
|
|
CopyRGBA(sourcePixel, targetPixel, flags);
|
||
|
|
// enable this pixel
|
||
|
|
mask |= ( 1 << ( 4*py + px ) );
|
||
|
|
}
|
||
|
|
|
||
|
|
// advance to the next pixel
|
||
|
|
targetPixel += 4;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// compress it into the output
|
||
|
|
CompressMasked( sourceRgba, mask, targetBlock, flags, metric );
|
||
|
|
|
||
|
|
// advance
|
||
|
|
targetBlock += bytesPerBlock;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void CompressImage( u8 const* rgba, int width, int height, void* blocks, int flags, float* metric )
|
||
|
|
{
|
||
|
|
CompressImage(rgba, width, height, width*4, blocks, flags, metric);
|
||
|
|
}
|
||
|
|
|
||
|
|
void DecompressImage( u8* rgba, int width, int height, int pitch, void const* blocks, int flags )
|
||
|
|
{
|
||
|
|
// fix any bad flags
|
||
|
|
flags = FixFlags( flags );
|
||
|
|
|
||
|
|
// loop over blocks
|
||
|
|
#ifdef SQUISH_USE_OPENMP
|
||
|
|
# pragma omp parallel for
|
||
|
|
#endif
|
||
|
|
for( int y = 0; y < height; y += 4 )
|
||
|
|
{
|
||
|
|
// initialise the block input
|
||
|
|
u8 const* sourceBlock = reinterpret_cast< u8 const* >( blocks );
|
||
|
|
int bytesPerBlock = ( ( flags & ( kDxt1 | kBc4 ) ) != 0 ) ? 8 : 16;
|
||
|
|
sourceBlock += ( (y / 4) * ( (width + 3) / 4) ) * bytesPerBlock;
|
||
|
|
|
||
|
|
for( int x = 0; x < width; x += 4 )
|
||
|
|
{
|
||
|
|
// decompress the block
|
||
|
|
u8 targetRgba[4*16];
|
||
|
|
Decompress( targetRgba, sourceBlock, flags );
|
||
|
|
|
||
|
|
// write the decompressed pixels to the correct image locations
|
||
|
|
u8 const* sourcePixel = targetRgba;
|
||
|
|
for( int py = 0; py < 4; ++py )
|
||
|
|
{
|
||
|
|
for( int px = 0; px < 4; ++px )
|
||
|
|
{
|
||
|
|
// get the target location
|
||
|
|
int sx = x + px;
|
||
|
|
int sy = y + py;
|
||
|
|
|
||
|
|
// write if we're in the image
|
||
|
|
if( sx < width && sy < height )
|
||
|
|
{
|
||
|
|
// copy the rgba value
|
||
|
|
u8* targetPixel = rgba + pitch*sy + 4*sx;
|
||
|
|
CopyRGBA(sourcePixel, targetPixel, flags);
|
||
|
|
}
|
||
|
|
|
||
|
|
// advance to the next pixel
|
||
|
|
sourcePixel += 4;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// advance
|
||
|
|
sourceBlock += bytesPerBlock;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void DecompressImage( u8* rgba, int width, int height, void const* blocks, int flags )
|
||
|
|
{
|
||
|
|
DecompressImage( rgba, width, height, width*4, blocks, flags );
|
||
|
|
}
|
||
|
|
|
||
|
|
static double ErrorSq(double x, double y)
|
||
|
|
{
|
||
|
|
return (x - y) * (x - y);
|
||
|
|
}
|
||
|
|
|
||
|
|
static void ComputeBlockWMSE(u8 const *original, u8 const *compressed, unsigned int w, unsigned int h, double &cmse, double &amse)
|
||
|
|
{
|
||
|
|
// Computes the MSE for the block and weights it by the variance of the original block.
|
||
|
|
// If the variance of the original block is less than 4 (i.e. a standard deviation of 1 per channel)
|
||
|
|
// then the block is close to being a single colour. Quantisation errors in single colour blocks
|
||
|
|
// are easier to see than similar errors in blocks that contain more colours, particularly when there
|
||
|
|
// are many such blocks in a large area (eg a blue sky background) as they cause banding. Given that
|
||
|
|
// banding is easier to see than small errors in "complex" blocks, we weight the errors by a factor
|
||
|
|
// of 5. This implies that images with large, single colour areas will have a higher potential WMSE
|
||
|
|
// than images with lots of detail.
|
||
|
|
|
||
|
|
cmse = amse = 0;
|
||
|
|
unsigned int sum_p[4]; // per channel sum of pixels
|
||
|
|
unsigned int sum_p2[4]; // per channel sum of pixels squared
|
||
|
|
memset(sum_p, 0, sizeof(sum_p));
|
||
|
|
memset(sum_p2, 0, sizeof(sum_p2));
|
||
|
|
for( unsigned int py = 0; py < 4; ++py )
|
||
|
|
{
|
||
|
|
for( unsigned int px = 0; px < 4; ++px )
|
||
|
|
{
|
||
|
|
if( px < w && py < h )
|
||
|
|
{
|
||
|
|
double pixelCMSE = 0;
|
||
|
|
for( int i = 0; i < 3; ++i )
|
||
|
|
{
|
||
|
|
pixelCMSE += ErrorSq(original[i], compressed[i]);
|
||
|
|
sum_p[i] += original[i];
|
||
|
|
sum_p2[i] += (unsigned int)original[i]*original[i];
|
||
|
|
}
|
||
|
|
if( original[3] == 0 && compressed[3] == 0 )
|
||
|
|
pixelCMSE = 0; // transparent in both, so colour is inconsequential
|
||
|
|
amse += ErrorSq(original[3], compressed[3]);
|
||
|
|
cmse += pixelCMSE;
|
||
|
|
sum_p[3] += original[3];
|
||
|
|
sum_p2[3] += (unsigned int)original[3]*original[3];
|
||
|
|
}
|
||
|
|
original += 4;
|
||
|
|
compressed += 4;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
unsigned int variance = 0;
|
||
|
|
for( int i = 0; i < 4; ++i )
|
||
|
|
variance += w*h*sum_p2[i] - sum_p[i]*sum_p[i];
|
||
|
|
if( variance < 4 * w * w * h * h )
|
||
|
|
{
|
||
|
|
amse *= 5;
|
||
|
|
cmse *= 5;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void ComputeMSE( u8 const *rgba, int width, int height, int pitch, u8 const *dxt, int flags, double &colourMSE, double &alphaMSE )
|
||
|
|
{
|
||
|
|
// fix any bad flags
|
||
|
|
flags = FixFlags( flags );
|
||
|
|
colourMSE = alphaMSE = 0;
|
||
|
|
|
||
|
|
// initialise the block input
|
||
|
|
squish::u8 const* sourceBlock = dxt;
|
||
|
|
int bytesPerBlock = ( ( flags & squish::kDxt1 ) != 0 ) ? 8 : 16;
|
||
|
|
|
||
|
|
// loop over blocks
|
||
|
|
for( int y = 0; y < height; y += 4 )
|
||
|
|
{
|
||
|
|
for( int x = 0; x < width; x += 4 )
|
||
|
|
{
|
||
|
|
// decompress the block
|
||
|
|
u8 targetRgba[4*16];
|
||
|
|
Decompress( targetRgba, sourceBlock, flags );
|
||
|
|
u8 const* sourcePixel = targetRgba;
|
||
|
|
|
||
|
|
// copy across to a similar pixel block
|
||
|
|
u8 originalRgba[4*16];
|
||
|
|
u8* originalPixel = originalRgba;
|
||
|
|
|
||
|
|
for( int py = 0; py < 4; ++py )
|
||
|
|
{
|
||
|
|
for( int px = 0; px < 4; ++px )
|
||
|
|
{
|
||
|
|
int sx = x + px;
|
||
|
|
int sy = y + py;
|
||
|
|
if( sx < width && sy < height )
|
||
|
|
{
|
||
|
|
u8 const* targetPixel = rgba + pitch*sy + 4*sx;
|
||
|
|
CopyRGBA(targetPixel, originalPixel, flags);
|
||
|
|
}
|
||
|
|
sourcePixel += 4;
|
||
|
|
originalPixel += 4;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// compute the weighted MSE of the block
|
||
|
|
double blockCMSE, blockAMSE;
|
||
|
|
ComputeBlockWMSE(originalRgba, targetRgba, std::min(4, width - x), std::min(4, height - y), blockCMSE, blockAMSE);
|
||
|
|
colourMSE += blockCMSE;
|
||
|
|
alphaMSE += blockAMSE;
|
||
|
|
// advance
|
||
|
|
sourceBlock += bytesPerBlock;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
colourMSE /= (width * height * 3);
|
||
|
|
alphaMSE /= (width * height);
|
||
|
|
}
|
||
|
|
|
||
|
|
void ComputeMSE( u8 const *rgba, int width, int height, u8 const *dxt, int flags, double &colourMSE, double &alphaMSE )
|
||
|
|
{
|
||
|
|
ComputeMSE(rgba, width, height, width*4, dxt, flags, colourMSE, alphaMSE);
|
||
|
|
}
|
||
|
|
|
||
|
|
} // namespace squish
|