raze-gles/source/common/textures/formats/pngtexture.cpp
2021-05-21 21:06:11 +02:00

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/*
** pngtexture.cpp
** Texture class for PNG images
**
**---------------------------------------------------------------------------
** Copyright 2004-2007 Randy Heit
** Copyright 2005-2019 Christoph Oelckers
** All rights reserved.
**
** Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions
** are met:
**
** 1. Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** 2. Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in the
** documentation and/or other materials provided with the distribution.
** 3. The name of the author may not be used to endorse or promote products
** derived from this software without specific prior written permission.
**
** THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
** IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
** OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
** IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
** NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
** THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
**---------------------------------------------------------------------------
**
**
*/
#include "files.h"
#include "templates.h"
#include "m_png.h"
#include "bitmap.h"
#include "imagehelpers.h"
#include "image.h"
#include "printf.h"
#include "texturemanager.h"
#include "filesystem.h"
//==========================================================================
//
// A PNG texture
//
//==========================================================================
class FPNGTexture : public FImageSource
{
public:
FPNGTexture (FileReader &lump, int lumpnum, int width, int height, uint8_t bitdepth, uint8_t colortype, uint8_t interlace);
int CopyPixels(FBitmap *bmp, int conversion) override;
TArray<uint8_t> CreatePalettedPixels(int conversion) override;
protected:
void ReadAlphaRemap(FileReader *lump, uint8_t *alpharemap);
void SetupPalette(FileReader &lump);
uint8_t BitDepth;
uint8_t ColorType;
uint8_t Interlace;
bool HaveTrans;
uint16_t NonPaletteTrans[3];
uint8_t *PaletteMap = nullptr;
int PaletteSize = 0;
uint32_t StartOfIDAT = 0;
uint32_t StartOfPalette = 0;
};
FImageSource* StbImage_TryCreate(FileReader& file, int lumpnum);
//==========================================================================
//
//
//
//==========================================================================
FImageSource *PNGImage_TryCreate(FileReader & data, int lumpnum)
{
union
{
uint32_t dw;
uint16_t w[2];
uint8_t b[4];
} first4bytes;
// This is most likely a PNG, but make sure. (Note that if the
// first 4 bytes match, but later bytes don't, we assume it's
// a corrupt PNG.)
data.Seek(0, FileReader::SeekSet);
if (data.Read (first4bytes.b, 4) != 4) return NULL;
if (first4bytes.dw != MAKE_ID(137,'P','N','G')) return NULL;
if (data.Read (first4bytes.b, 4) != 4) return NULL;
if (first4bytes.dw != MAKE_ID(13,10,26,10)) return NULL;
if (data.Read (first4bytes.b, 4) != 4) return NULL;
if (first4bytes.dw != MAKE_ID(0,0,0,13)) return NULL;
if (data.Read (first4bytes.b, 4) != 4) return NULL;
if (first4bytes.dw != MAKE_ID('I','H','D','R')) return NULL;
// The PNG looks valid so far. Check the IHDR to make sure it's a
// type of PNG we support.
int width = data.ReadInt32BE();
int height = data.ReadInt32BE();
uint8_t bitdepth = data.ReadUInt8();
uint8_t colortype = data.ReadUInt8();
uint8_t compression = data.ReadUInt8();
uint8_t filter = data.ReadUInt8();
uint8_t interlace = data.ReadUInt8();
if (compression != 0 || filter != 0 || interlace > 1)
{
Printf(TEXTCOLOR_YELLOW"WARNING: failed to load PNG %s: the compression, filter, or interlace is not supported!\n", fileSystem.GetFileFullName(lumpnum));
return NULL;
}
if (!((1 << colortype) & 0x5D))
{
Printf(TEXTCOLOR_YELLOW"WARNING: failed to load PNG %s: the colortype (%u) is not supported!\n", fileSystem.GetFileFullName(lumpnum), colortype);
return NULL;
}
if (!((1 << bitdepth) & 0x116))
{
// Try STBImage for 16 bit PNGs.
auto tex = StbImage_TryCreate(data, lumpnum);
if (tex)
{
// STBImage does not handle grAb, so do that here and insert the data into the texture.
data.Seek(33, FileReader::SeekSet);
int len = data.ReadInt32BE();
int id = data.ReadInt32();
while (id != MAKE_ID('I', 'D', 'A', 'T') && id != MAKE_ID('I', 'E', 'N', 'D'))
{
if (id != MAKE_ID('g', 'r', 'A', 'b'))
{
data.Seek(len, FileReader::SeekCur);
}
else
{
int ihotx = data.ReadInt32BE();
int ihoty = data.ReadInt32BE();
if (ihotx < -32768 || ihotx > 32767)
{
Printf("X-Offset for PNG texture %s is bad: %d (0x%08x)\n", fileSystem.GetFileFullName(lumpnum), ihotx, ihotx);
ihotx = 0;
}
if (ihoty < -32768 || ihoty > 32767)
{
Printf("Y-Offset for PNG texture %s is bad: %d (0x%08x)\n", fileSystem.GetFileFullName(lumpnum), ihoty, ihoty);
ihoty = 0;
}
tex->SetOffsets(ihotx, ihoty);
}
data.Seek(4, FileReader::SeekCur); // Skip CRC
len = data.ReadInt32BE();
id = MAKE_ID('I', 'E', 'N', 'D');
id = data.ReadInt32();
}
return tex;
}
Printf(TEXTCOLOR_YELLOW"WARNING: failed to load PNG %s: the bit-depth (%u) is not supported!\n", fileSystem.GetFileFullName(lumpnum), bitdepth);
return NULL;
}
// Just for completeness, make sure the PNG has something more than an IHDR.
data.Seek (4, FileReader::SeekSet);
data.Read (first4bytes.b, 4);
if (first4bytes.dw == 0)
{
if (data.Read(first4bytes.b, 4) != 4 || first4bytes.dw == MAKE_ID('I','E','N','D'))
{
Printf(TEXTCOLOR_YELLOW"WARNING: failed to load PNG %s: the file ends immediately after the IHDR.\n", fileSystem.GetFileFullName(lumpnum));
return NULL;
}
}
return new FPNGTexture (data, lumpnum, width, height, bitdepth, colortype, interlace);
}
//==========================================================================
//
//
//
//==========================================================================
FPNGTexture::FPNGTexture (FileReader &lump, int lumpnum, int width, int height,
uint8_t depth, uint8_t colortype, uint8_t interlace)
: FImageSource(lumpnum),
BitDepth(depth), ColorType(colortype), Interlace(interlace), HaveTrans(false)
{
uint8_t trans[256];
uint32_t len, id;
int i;
bMasked = false;
Width = width;
Height = height;
memset(trans, 255, 256);
// Parse pre-IDAT chunks. I skip the CRCs. Is that bad?
lump.Seek(33, FileReader::SeekSet);
lump.Read(&len, 4);
lump.Read(&id, 4);
while (id != MAKE_ID('I','D','A','T') && id != MAKE_ID('I','E','N','D'))
{
len = BigLong((unsigned int)len);
switch (id)
{
default:
lump.Seek (len, FileReader::SeekCur);
break;
case MAKE_ID('g','r','A','b'):
// This is like GRAB found in an ILBM, except coordinates use 4 bytes
{
int ihotx = lump.ReadInt32BE();
int ihoty = lump.ReadInt32BE();
if (ihotx < -32768 || ihotx > 32767)
{
Printf ("X-Offset for PNG texture %s is bad: %d (0x%08x)\n", fileSystem.GetFileFullName (lumpnum), ihotx, ihotx);
ihotx = 0;
}
if (ihoty < -32768 || ihoty > 32767)
{
Printf ("Y-Offset for PNG texture %s is bad: %d (0x%08x)\n", fileSystem.GetFileFullName (lumpnum), ihoty, ihoty);
ihoty = 0;
}
LeftOffset = ihotx;
TopOffset = ihoty;
}
break;
case MAKE_ID('P','L','T','E'):
PaletteSize = MIN<int> (len / 3, 256);
StartOfPalette = (uint32_t)lump.Tell();
lump.Seek(len, FileReader::SeekCur);
break;
case MAKE_ID('t','R','N','S'):
lump.Read (trans, len);
HaveTrans = true;
// Save for colortype 2
NonPaletteTrans[0] = uint16_t(trans[0] * 256 + trans[1]);
NonPaletteTrans[1] = uint16_t(trans[2] * 256 + trans[3]);
NonPaletteTrans[2] = uint16_t(trans[4] * 256 + trans[5]);
break;
}
lump.Seek(4, FileReader::SeekCur); // Skip CRC
lump.Read(&len, 4);
id = MAKE_ID('I','E','N','D');
lump.Read(&id, 4);
}
StartOfIDAT = (uint32_t)lump.Tell() - 8;
switch (colortype)
{
case 4: // Grayscale + Alpha
bMasked = true;
// intentional fall-through
case 0: // Grayscale
if (colortype == 0 && HaveTrans && NonPaletteTrans[0] < 256)
{
bMasked = true;
PaletteSize = 256;
}
else
{
PaletteMap = GPalette.GrayMap;
}
break;
case 3: // Paletted
for (i = 0; i < PaletteSize; ++i)
{
if (trans[i] == 0)
{
bMasked = true;
}
}
break;
case 6: // RGB + Alpha
bMasked = true;
break;
case 2: // RGB
bMasked = HaveTrans;
break;
}
}
void FPNGTexture::SetupPalette(FileReader &lump)
{
union
{
uint32_t palette[256];
uint8_t pngpal[256][3];
} p;
uint8_t trans[256];
uint32_t len, id;
int i;
auto pos = lump.Tell();
memset(trans, 255, 256);
// Parse pre-IDAT chunks. I skip the CRCs. Is that bad?
lump.Seek(33, FileReader::SeekSet);
lump.Read(&len, 4);
lump.Read(&id, 4);
while (id != MAKE_ID('I', 'D', 'A', 'T') && id != MAKE_ID('I', 'E', 'N', 'D'))
{
len = BigLong((unsigned int)len);
switch (id)
{
default:
lump.Seek(len, FileReader::SeekCur);
break;
case MAKE_ID('P', 'L', 'T', 'E'):
lump.Read(p.pngpal, PaletteSize * 3);
if (PaletteSize * 3 != (int)len)
{
lump.Seek(len - PaletteSize * 3, FileReader::SeekCur);
}
for (i = PaletteSize - 1; i >= 0; --i)
{
p.palette[i] = MAKERGB(p.pngpal[i][0], p.pngpal[i][1], p.pngpal[i][2]);
}
break;
case MAKE_ID('t', 'R', 'N', 'S'):
lump.Read(trans, len);
break;
}
lump.Seek(4, FileReader::SeekCur); // Skip CRC
lump.Read(&len, 4);
id = MAKE_ID('I', 'E', 'N', 'D');
lump.Read(&id, 4);
}
StartOfIDAT = (uint32_t)lump.Tell() - 8;
switch (ColorType)
{
case 0: // Grayscale
if (HaveTrans && NonPaletteTrans[0] < 256)
{
PaletteMap = (uint8_t*)ImageArena.Alloc(PaletteSize);
memcpy(PaletteMap, GPalette.GrayMap, 256);
PaletteMap[NonPaletteTrans[0]] = 0;
}
break;
case 3: // Paletted
PaletteMap = (uint8_t*)ImageArena.Alloc(PaletteSize);
MakeRemap((uint32_t*)GPalette.BaseColors, p.palette, PaletteMap, trans, PaletteSize);
for (i = 0; i < PaletteSize; ++i)
{
if (trans[i] == 0)
{
PaletteMap[i] = 0;
}
}
break;
default:
break;
}
lump.Seek(pos, FileReader::SeekSet);
}
//==========================================================================
//
//
//
//==========================================================================
void FPNGTexture::ReadAlphaRemap(FileReader *lump, uint8_t *alpharemap)
{
auto p = lump->Tell();
lump->Seek(StartOfPalette, FileReader::SeekSet);
for (int i = 0; i < PaletteSize; i++)
{
uint8_t r = lump->ReadUInt8();
uint8_t g = lump->ReadUInt8();
uint8_t b = lump->ReadUInt8();
int palmap = PaletteMap ? PaletteMap[i] : i;
alpharemap[i] = palmap == 0 ? 0 : Luminance(r, g, b);
}
lump->Seek(p, FileReader::SeekSet);
}
//==========================================================================
//
//
//
//==========================================================================
TArray<uint8_t> FPNGTexture::CreatePalettedPixels(int conversion)
{
FileReader *lump;
FileReader lfr;
lfr = fileSystem.OpenFileReader(SourceLump);
lump = &lfr;
TArray<uint8_t> Pixels(Width*Height, true);
if (StartOfIDAT == 0)
{
memset (Pixels.Data(), 0x99, Width*Height);
}
else
{
uint32_t len, id;
lump->Seek (StartOfIDAT, FileReader::SeekSet);
lump->Read(&len, 4);
lump->Read(&id, 4);
bool alphatex = conversion == luminance;
if (ColorType == 0 || ColorType == 3) /* Grayscale and paletted */
{
M_ReadIDAT (*lump, Pixels.Data(), Width, Height, Width, BitDepth, ColorType, Interlace, BigLong((unsigned int)len));
if (Width == Height)
{
if (conversion != luminance)
{
if (!PaletteMap) SetupPalette(lfr);
ImageHelpers::FlipSquareBlockRemap (Pixels.Data(), Width, PaletteMap);
}
else if (ColorType == 0)
{
ImageHelpers::FlipSquareBlock (Pixels.Data(), Width);
}
else
{
uint8_t alpharemap[256];
ReadAlphaRemap(lump, alpharemap);
ImageHelpers::FlipSquareBlockRemap(Pixels.Data(), Width, alpharemap);
}
}
else
{
TArray<uint8_t> newpix(Width*Height, true);
if (conversion != luminance)
{
if (!PaletteMap) SetupPalette(lfr);
ImageHelpers::FlipNonSquareBlockRemap (newpix.Data(), Pixels.Data(), Width, Height, Width, PaletteMap);
}
else if (ColorType == 0)
{
ImageHelpers::FlipNonSquareBlock (newpix.Data(), Pixels.Data(), Width, Height, Width);
}
else
{
uint8_t alpharemap[256];
ReadAlphaRemap(lump, alpharemap);
ImageHelpers::FlipNonSquareBlockRemap(newpix.Data(), Pixels.Data(), Width, Height, Width, alpharemap);
}
return newpix;
}
}
else /* RGB and/or Alpha present */
{
int bytesPerPixel = ColorType == 2 ? 3 : ColorType == 4 ? 2 : 4;
uint8_t *tempix = new uint8_t[Width * Height * bytesPerPixel];
uint8_t *in, *out;
int x, y, pitch, backstep;
M_ReadIDAT (*lump, tempix, Width, Height, Width*bytesPerPixel, BitDepth, ColorType, Interlace, BigLong((unsigned int)len));
in = tempix;
out = Pixels.Data();
// Convert from source format to paletted, column-major.
// Formats with alpha maps are reduced to only 1 bit of alpha.
switch (ColorType)
{
case 2: // RGB
pitch = Width * 3;
backstep = Height * pitch - 3;
for (x = Width; x > 0; --x)
{
for (y = Height; y > 0; --y)
{
if (HaveTrans && in[0] == NonPaletteTrans[0] && in[1] == NonPaletteTrans[1] && in[2] == NonPaletteTrans[2])
{
*out++ = 0;
}
else
{
*out++ = ImageHelpers::RGBToPalette(alphatex, in[0], in[1], in[2]);
}
in += pitch;
}
in -= backstep;
}
break;
case 4: // Grayscale + Alpha
pitch = Width * 2;
backstep = Height * pitch - 2;
if (!PaletteMap) SetupPalette(lfr);
for (x = Width; x > 0; --x)
{
for (y = Height; y > 0; --y)
{
*out++ = alphatex? ((in[0] * in[1]) / 255) : in[1] < 128 ? 0 : PaletteMap[in[0]];
in += pitch;
}
in -= backstep;
}
break;
case 6: // RGB + Alpha
pitch = Width * 4;
backstep = Height * pitch - 4;
for (x = Width; x > 0; --x)
{
for (y = Height; y > 0; --y)
{
*out++ = ImageHelpers::RGBToPalette(alphatex, in[0], in[1], in[2], in[3]);
in += pitch;
}
in -= backstep;
}
break;
}
delete[] tempix;
}
}
return Pixels;
}
//===========================================================================
//
// FPNGTexture::CopyPixels
//
//===========================================================================
int FPNGTexture::CopyPixels(FBitmap *bmp, int conversion)
{
// Parse pre-IDAT chunks. I skip the CRCs. Is that bad?
PalEntry pe[256];
uint32_t len, id;
static char bpp[] = {1, 0, 3, 1, 2, 0, 4};
int pixwidth = Width * bpp[ColorType];
int transpal = false;
FileReader *lump;
FileReader lfr;
lfr = fileSystem.OpenFileReader(SourceLump);
lump = &lfr;
lump->Seek(33, FileReader::SeekSet);
for(int i = 0; i < 256; i++) // default to a gray map
pe[i] = PalEntry(255,i,i,i);
lump->Read(&len, 4);
lump->Read(&id, 4);
while (id != MAKE_ID('I','D','A','T') && id != MAKE_ID('I','E','N','D'))
{
len = BigLong((unsigned int)len);
switch (id)
{
default:
lump->Seek (len, FileReader::SeekCur);
break;
case MAKE_ID('P','L','T','E'):
for(int i = 0; i < PaletteSize; i++)
{
pe[i].r = lump->ReadUInt8();
pe[i].g = lump->ReadUInt8();
pe[i].b = lump->ReadUInt8();
}
break;
case MAKE_ID('t','R','N','S'):
if (ColorType == 3)
{
for(uint32_t i = 0; i < len; i++)
{
pe[i].a = lump->ReadUInt8();
if (pe[i].a != 0 && pe[i].a != 255)
transpal = true;
}
}
else
{
lump->Seek(len, FileReader::SeekCur);
}
break;
}
lump->Seek(4, FileReader::SeekCur); // Skip CRC
lump->Read(&len, 4);
id = MAKE_ID('I','E','N','D');
lump->Read(&id, 4);
}
if (ColorType == 0 && HaveTrans && NonPaletteTrans[0] < 256)
{
pe[NonPaletteTrans[0]].a = 0;
transpal = true;
}
uint8_t * Pixels = new uint8_t[pixwidth * Height];
lump->Seek (StartOfIDAT, FileReader::SeekSet);
lump->Read(&len, 4);
lump->Read(&id, 4);
M_ReadIDAT (*lump, Pixels, Width, Height, pixwidth, BitDepth, ColorType, Interlace, BigLong((unsigned int)len));
switch (ColorType)
{
case 0:
case 3:
bmp->CopyPixelData(0, 0, Pixels, Width, Height, 1, Width, 0, pe);
break;
case 2:
if (!HaveTrans)
{
bmp->CopyPixelDataRGB(0, 0, Pixels, Width, Height, 3, pixwidth, 0, CF_RGB);
}
else
{
bmp->CopyPixelDataRGB(0, 0, Pixels, Width, Height, 3, pixwidth, 0, CF_RGBT, nullptr,
NonPaletteTrans[0], NonPaletteTrans[1], NonPaletteTrans[2]);
transpal = true;
}
break;
case 4:
bmp->CopyPixelDataRGB(0, 0, Pixels, Width, Height, 2, pixwidth, 0, CF_IA);
transpal = -1;
break;
case 6:
bmp->CopyPixelDataRGB(0, 0, Pixels, Width, Height, 4, pixwidth, 0, CF_RGBA);
transpal = -1;
break;
default:
break;
}
delete[] Pixels;
return transpal;
}
#include "textures.h"
//==========================================================================
//
// A savegame picture
// This is essentially a stripped down version of the PNG texture
// only supporting the features actually present in a savegame
// that does not use an image source, because image sources are not
// meant to be transient data like the savegame picture.
//
//==========================================================================
class FPNGFileTexture : public FTexture
{
public:
FPNGFileTexture (FileReader &lump, int width, int height, uint8_t colortype);
virtual FBitmap GetBgraBitmap(const PalEntry *remap, int *trans) override;
protected:
FileReader fr;
uint8_t ColorType;
int PaletteSize;
};
//==========================================================================
//
//
//
//==========================================================================
FGameTexture *PNGTexture_CreateFromFile(PNGHandle *png, const FString &filename)
{
if (M_FindPNGChunk(png, MAKE_ID('I','H','D','R')) == 0)
{
return nullptr;
}
// Savegame images can only be either 8 bit paletted or 24 bit RGB
auto &data = png->File;
int width = data.ReadInt32BE();
int height = data.ReadInt32BE();
uint8_t bitdepth = data.ReadUInt8();
uint8_t colortype = data.ReadUInt8();
uint8_t compression = data.ReadUInt8();
uint8_t filter = data.ReadUInt8();
uint8_t interlace = data.ReadUInt8();
// Reject anything that cannot be put into a savegame picture by GZDoom itself.
if (compression != 0 || filter != 0 || interlace > 0 || bitdepth != 8 || (colortype != 2 && colortype != 3)) return nullptr;
else return MakeGameTexture(new FPNGFileTexture (png->File, width, height, colortype), nullptr, ETextureType::Override);
}
//==========================================================================
//
//
//
//==========================================================================
FPNGFileTexture::FPNGFileTexture (FileReader &lump, int width, int height, uint8_t colortype)
: ColorType(colortype)
{
Width = width;
Height = height;
Masked = false;
bTranslucent = false;
fr = std::move(lump);
}
//===========================================================================
//
// FPNGTexture::CopyPixels
//
//===========================================================================
FBitmap FPNGFileTexture::GetBgraBitmap(const PalEntry *remap, int *trans)
{
FBitmap bmp;
// Parse pre-IDAT chunks. I skip the CRCs. Is that bad?
PalEntry pe[256];
uint32_t len, id;
int pixwidth = Width * (ColorType == 2? 3:1);
FileReader *lump = &fr;
bmp.Create(Width, Height);
lump->Seek(33, FileReader::SeekSet);
lump->Read(&len, 4);
lump->Read(&id, 4);
while (id != MAKE_ID('I','D','A','T') && id != MAKE_ID('I','E','N','D'))
{
len = BigLong((unsigned int)len);
if (id != MAKE_ID('P','L','T','E'))
lump->Seek (len, FileReader::SeekCur);
else
{
PaletteSize = std::min<int> (len / 3, 256);
for(int i = 0; i < PaletteSize; i++)
{
pe[i].r = lump->ReadUInt8();
pe[i].g = lump->ReadUInt8();
pe[i].b = lump->ReadUInt8();
pe[i].a = 255;
}
}
lump->Seek(4, FileReader::SeekCur); // Skip CRC
lump->Read(&len, 4);
id = MAKE_ID('I','E','N','D');
lump->Read(&id, 4);
}
auto StartOfIDAT = (uint32_t)lump->Tell() - 8;
TArray<uint8_t> Pixels(pixwidth * Height);
lump->Seek (StartOfIDAT, FileReader::SeekSet);
lump->Read(&len, 4);
lump->Read(&id, 4);
M_ReadIDAT (*lump, Pixels.Data(), Width, Height, pixwidth, 8, ColorType, 0, BigLong((unsigned int)len));
if (ColorType == 3)
{
bmp.CopyPixelData(0, 0, Pixels.Data(), Width, Height, 1, Width, 0, pe);
}
else
{
bmp.CopyPixelDataRGB(0, 0, Pixels.Data(), Width, Height, 3, pixwidth, 0, CF_RGB);
}
return bmp;
}