public static void ReadPixels(ref BITMAP_READ_DETAILS info, BitmapCorePixelFormat imgDestFmt, byte *sourceBufferStart, byte *destBufferStart, uint bcrFlags)
{
bool forcebgra32 = (bcrFlags & BC_READ_FORCE_BGRA32) > 0;
bool preserveFormat = (bcrFlags & BC_READ_STRICT_PRESERVE_FORMAT) > 0;
bool preserveAlpha = (bcrFlags & BC_READ_PRESERVE_INVALID_ALPHA) > 0;
bool ignoreColorProfile = (bcrFlags & BC_READ_IGNORE_COLOR_PROFILE) > 0;
if (preserveFormat && (info.imgSourceFmt != imgDestFmt))
{
throw new NotSupportedException("StrictPreserveFormat was set while the source and/or target format is not supported.");
}
if (forcebgra32 && imgDestFmt != BitmapCorePixelFormat.Bgra32)
{
throw new InvalidOperationException("ForceBGRA32 was set but this is not supported with the source pixel format.");
}
if (imgDestFmt == null)
{
throw new ArgumentNullException(nameof(imgDestFmt));
}
var compr = info.compression;
if (compr == BitmapCompressionMode.BI_JPEG || compr == BitmapCompressionMode.BI_PNG)
{
throw new NotSupportedException("BI_JPEG and BI_PNG passthrough compression is not supported.");
}
else if (compr == BitmapCompressionMode.BI_RLE4 || compr == BitmapCompressionMode.BI_RLE8 || compr == BitmapCompressionMode.OS2_RLE24)
{
if (imgDestFmt != BitmapCorePixelFormat.Bgra32)
{
throw new NotSupportedException("RLE only supports being translated to Bgra32");
}
BitmapCorePixelReader.ReadRLE_32(ref info, sourceBufferStart, destBufferStart);
}
else if (compr == BitmapCompressionMode.OS2_HUFFMAN1D)
{
BitmapCorePixelReader.ReadHuffmanG31D(ref info, sourceBufferStart, destBufferStart);
}
else if (info.imgSourceFmt == imgDestFmt && info.cTrueAlpha == imgDestFmt.HasAlpha)
{
// if the source is a known/supported/standard format, we can basically just copy the buffer straight over with no further processing
if (info.imgTopDown)
{
var size = info.imgStride * info.imgHeight;
Buffer.MemoryCopy(sourceBufferStart, destBufferStart, size, size);
}
else
{
uint stride = info.imgStride;
int y, height = info.imgHeight, h = height;
while (--h >= 0)
{
y = height - h - 1;
byte *sourceln = sourceBufferStart + (y * stride);
byte *destln = destBufferStart + (h * stride);
Buffer.MemoryCopy(sourceln, destln, stride, stride);
}
}
}
else if (info.bbp <= 8)
{
if (imgDestFmt != BitmapCorePixelFormat.Bgra32)
{
throw new NotSupportedException("RLE only supports being translated to Bgra32");
}
BitmapCorePixelReader.ReadIndexedTo32(ref info, sourceBufferStart, destBufferStart);
}
else if (info.bbp > 8)
{
BitmapCorePixelReader.ConvertChannelBGRA(ref info, imgDestFmt, sourceBufferStart, destBufferStart, preserveAlpha);
}
else
{
throw new NotSupportedException("Pixel format / compression not supported");
}
// translate pixels to sRGB via embedded color profile
if (!ignoreColorProfile && info.colorProfile != null && !info.colorProfile.IsInvalid && !imgDestFmt.IsIndexed && imgDestFmt.MscmsFormat.HasValue)
{
try
{
uint stride = StructUtil.CalcStride(imgDestFmt.BitsPerPixel, info.imgWidth);
mscms.TransformPixelsTo_sRGB(info.colorProfile, imgDestFmt.MscmsFormat.Value, destBufferStart, info.imgWidth, info.imgHeight, stride, info.colorProfileIntent);
}
catch
{
// ignore color transformation errors
}
}
}
public static void ReadHeader(byte *source, int sourceLength, out BITMAP_READ_DETAILS info, uint bcrFlags)
{
var ptr = source;
if ((sourceLength) < 12) // min header size
{
throw new InvalidOperationException(ERR_HEOF);
}
bool hasFileHeader = StructUtil.ReadU16(ptr) == BFH_BM;
var size_fh = Marshal.SizeOf <BITMAPFILEHEADER>();
int offset = 0;
var fh = default(BITMAPFILEHEADER);
if (hasFileHeader)
{
var fhsize = Marshal.SizeOf <BITMAPFILEHEADER>();
if (offset + fhsize > sourceLength)
{
throw new InvalidOperationException(ERR_HEOF);
}
fh = StructUtil.Deserialize <BITMAPFILEHEADER>(ptr);
ptr += fhsize;
offset += fhsize;
}
// we'll just unpack all the various header types we support into a standard BMPV5 header
// this makes subsequent code easier to maintain as it only needs to refer to one place
if ((sourceLength - offset) < 12) // min header size
{
throw new InvalidOperationException(ERR_HEOF);
}
var header_size = StructUtil.ReadU32(ptr);
var bi = default(BITMAPV5HEADER);
bool is_os21x_ = false;
if (header_size == 12)
{
var bich = StructUtil.Deserialize <BITMAPCOREHEADER>(ptr);
bi.bV5Size = bich.bcSize;
bi.bV5Width = bich.bcWidth;
bi.bV5Height = bich.bcHeight;
bi.bV5Planes = bich.bcPlanes;
bi.bV5BitCount = bich.bcBitCount;
bi.bV5CSType = ColorSpaceType.LCS_sRGB;
is_os21x_ = true;
}
else if (/*header_size == 14 || */ header_size == 16 || header_size == 42 || header_size == 46 || header_size == 64)
{
var biih = StructUtil.Deserialize <BITMAPINFOHEADER>(ptr);
bi.bV5Size = biih.bV5Size;
bi.bV5Width = biih.bV5Width;
bi.bV5Height = biih.bV5Height;
bi.bV5Planes = biih.bV5Planes;
bi.bV5BitCount = biih.bV5BitCount;
if (header_size > 16)
{
bi.bV5Compression = biih.bV5Compression;
bi.bV5SizeImage = biih.bV5SizeImage;
bi.bV5XPelsPerMeter = biih.bV5XPelsPerMeter;
bi.bV5YPelsPerMeter = biih.bV5YPelsPerMeter;
bi.bV5ClrUsed = biih.bV5ClrUsed;
bi.bV5ClrImportant = biih.bV5ClrImportant;
}
// https://www.fileformat.info/mirror/egff/ch09_05.htm (G31D)
if (bi.bV5Compression == (BitmapCompressionMode)3 && bi.bV5BitCount == 1)
{
bi.bV5Compression = BitmapCompressionMode.OS2_HUFFMAN1D;
}
else if (bi.bV5Compression == (BitmapCompressionMode)4 && bi.bV5BitCount == 24)
{
bi.bV5Compression = BitmapCompressionMode.OS2_RLE24;
}
bi.bV5CSType = ColorSpaceType.LCS_sRGB;
}
else if (header_size == 40)
{
var biih = StructUtil.Deserialize <BITMAPINFOHEADER>(ptr);
bi.bV5Size = biih.bV5Size;
bi.bV5Width = biih.bV5Width;
bi.bV5Height = biih.bV5Height;
bi.bV5Planes = biih.bV5Planes;
bi.bV5BitCount = biih.bV5BitCount;
bi.bV5Compression = biih.bV5Compression;
bi.bV5SizeImage = biih.bV5SizeImage;
bi.bV5XPelsPerMeter = biih.bV5XPelsPerMeter;
bi.bV5YPelsPerMeter = biih.bV5YPelsPerMeter;
bi.bV5ClrUsed = biih.bV5ClrUsed;
bi.bV5ClrImportant = biih.bV5ClrImportant;
bi.bV5CSType = ColorSpaceType.LCS_sRGB;
}
else if (header_size == 52 || header_size == 56)
{
var biih = StructUtil.Deserialize <BITMAPV3INFOHEADER>(ptr);
bi.bV5Size = biih.bV5Size;
bi.bV5Width = biih.bV5Width;
bi.bV5Height = biih.bV5Height;
bi.bV5Planes = biih.bV5Planes;
bi.bV5BitCount = biih.bV5BitCount;
bi.bV5Compression = biih.bV5Compression;
bi.bV5SizeImage = biih.bV5SizeImage;
bi.bV5XPelsPerMeter = biih.bV5XPelsPerMeter;
bi.bV5YPelsPerMeter = biih.bV5YPelsPerMeter;
bi.bV5ClrUsed = biih.bV5ClrUsed;
bi.bV5ClrImportant = biih.bV5ClrImportant;
bi.bV5RedMask = biih.bV5RedMask;
bi.bV5GreenMask = biih.bV5GreenMask;
bi.bV5BlueMask = biih.bV5BlueMask;
if (header_size == 56) // 56b header adds alpha mask
{
bi.bV5AlphaMask = biih.bV5AlphaMask;
}
bi.bV5CSType = ColorSpaceType.LCS_sRGB;
}
else if (header_size == 108)
{
var biih = StructUtil.Deserialize <BITMAPV4HEADER>(ptr);
bi.bV5Size = biih.bV5Size;
bi.bV5Width = biih.bV5Width;
bi.bV5Height = biih.bV5Height;
bi.bV5Planes = biih.bV5Planes;
bi.bV5BitCount = biih.bV5BitCount;
bi.bV5Compression = biih.bV5Compression;
bi.bV5SizeImage = biih.bV5SizeImage;
bi.bV5XPelsPerMeter = biih.bV5XPelsPerMeter;
bi.bV5YPelsPerMeter = biih.bV5YPelsPerMeter;
bi.bV5ClrUsed = biih.bV5ClrUsed;
bi.bV5ClrImportant = biih.bV5ClrImportant;
bi.bV5RedMask = biih.bV5RedMask;
bi.bV5GreenMask = biih.bV5GreenMask;
bi.bV5BlueMask = biih.bV5BlueMask;
bi.bV5AlphaMask = biih.bV5AlphaMask;
bi.bV5CSType = biih.bV5CSType;
bi.bV5Endpoints_1x = biih.bV5Endpoints_1x;
bi.bV5Endpoints_1y = biih.bV5Endpoints_1y;
bi.bV5Endpoints_1z = biih.bV5Endpoints_1z;
bi.bV5Endpoints_2x = biih.bV5Endpoints_2x;
bi.bV5Endpoints_2y = biih.bV5Endpoints_2y;
bi.bV5Endpoints_2z = biih.bV5Endpoints_2z;
bi.bV5Endpoints_3x = biih.bV5Endpoints_3x;
bi.bV5Endpoints_3y = biih.bV5Endpoints_3y;
bi.bV5Endpoints_3z = biih.bV5Endpoints_3z;
bi.bV5GammaRed = biih.bV5GammaRed;
bi.bV5GammaGreen = biih.bV5GammaGreen;
bi.bV5GammaBlue = biih.bV5GammaBlue;
}
else if (header_size == 124)
{
bi = StructUtil.Deserialize <BITMAPV5HEADER>(ptr);
}
else
{
throw new NotSupportedException($"Bitmap header size '{header_size}' not known / supported.");
}
ptr += header_size;
offset += (int)header_size;
ushort nbits = bi.bV5BitCount;
//if (bi.bV5Planes != 1)
// throw new NotSupportedException($"Bitmap bV5Planes of '{bi.bV5Planes}' is not supported.");
// we don't support linked profiles, custom windows profiles, etc - so default to sRGB instead of throwing...
if (bi.bV5CSType != ColorSpaceType.LCS_CALIBRATED_RGB && bi.bV5CSType != ColorSpaceType.PROFILE_EMBEDDED)
{
bi.bV5CSType = ColorSpaceType.LCS_sRGB;
}
uint maskR = 0;
uint maskG = 0;
uint maskB = 0;
uint maskA = 0;
bool hasAlphaChannel = false;
bool skipVerifyBppAndMasks = false;
switch (bi.bV5Compression)
{
case BitmapCompressionMode.BI_BITFIELDS:
var rgb = StructUtil.Deserialize <MASKTRIPLE>(ptr);
maskR = rgb.rgbRed;
maskG = rgb.rgbGreen;
maskB = rgb.rgbBlue;
offset += Marshal.SizeOf <MASKTRIPLE>();
break;
case BitmapCompressionMode.BI_ALPHABITFIELDS:
var rgba = StructUtil.Deserialize <MASKQUAD>(ptr);
maskR = rgba.rgbRed;
maskG = rgba.rgbGreen;
maskB = rgba.rgbBlue;
maskA = rgba.rgbAlpha;
offset += Marshal.SizeOf <MASKQUAD>();
hasAlphaChannel = true;
break;
case BitmapCompressionMode.BI_RGB:
switch (nbits)
{
case 32:
// windows wrongly uses the 4th byte of BI_RGB 32bit dibs as alpha
// but we need to do it too if we have any hope of reading alpha data
maskB = 0xff;
maskG = 0xff00;
maskR = 0xff0000;
maskA = 0xff000000; // fake transparency?
break;
case 24:
maskB = 0xff;
maskG = 0xff00;
maskR = 0xff0000;
break;
case 16:
maskB = 0x001f;
maskG = 0x03e0;
maskR = 0x7c00;
// we can check for transparency in 16b RGB but it is slower and is very uncommon
// maskA = 0x8000; // fake transparency?
break;
}
break;
case BitmapCompressionMode.BI_JPEG:
case BitmapCompressionMode.BI_PNG:
case BitmapCompressionMode.BI_RLE4:
case BitmapCompressionMode.BI_RLE8:
case BitmapCompressionMode.OS2_RLE24:
if (bi.bV5Height < 0)
{
throw new NotSupportedException("Top-down bitmaps are not supported with RLE/JPEG/PNG compression.");
}
skipVerifyBppAndMasks = true;
break;
case BitmapCompressionMode.OS2_HUFFMAN1D:
if (bi.bV5Height < 0)
{
throw new NotSupportedException("Top-down bitmaps are not supported with Huffman1D compression.");
}
if (bi.bV5BitCount != 1)
{
throw new NotSupportedException("Huffman1D compression is only supported with 1bpp bitmaps");
}
skipVerifyBppAndMasks = true;
break;
default:
throw new NotSupportedException($"Bitmap with bV5Compression of '{bi.bV5Compression.ToString()}' is not supported.");
}
// lets use the v3/v4/v5 masks if present instead of RGB
// according to some readers (FIREFOX!) these masks are only valid if the compression mode is
// BI_BITFIELDS, meaning they might write garbage here when the compression is RGB
if (bi.bV5Size >= 52 && bi.bV5Compression == BitmapCompressionMode.BI_BITFIELDS)
{
if (bi.bV5RedMask != 0)
{
maskR = bi.bV5RedMask;
}
if (bi.bV5BlueMask != 0)
{
maskB = bi.bV5BlueMask;
}
if (bi.bV5GreenMask != 0)
{
maskG = bi.bV5GreenMask;
}
}
// if an alpha mask has been provided in the header, lets use it.
if (bi.bV5Size >= 56 && bi.bV5AlphaMask != 0)
{
maskA = bi.bV5AlphaMask;
hasAlphaChannel = true;
}
// try to infer alpha if 32bpp & no alpha mask was set (ie, BI_BITFIELDS)
// this will only be used if the PRESERVE_FAKE_ALPHA flag is set
if (maskA == 0 && nbits == 32)
{
maskA = (maskB | maskG | maskR) ^ 0xFFFFFFFF;
}
bool smBit = nbits == 1 || nbits == 2 || nbits == 4 || nbits == 8;
bool lgBit = nbits == 16 || nbits == 24 || nbits == 32;
if (!skipVerifyBppAndMasks)
{
if (!lgBit && !smBit)
{
throw new NotSupportedException($"Bitmap with bits per pixel of '{nbits}' are not valid.");
}
if (lgBit && maskR == 0 && maskB == 0 && maskG == 0)
{
throw new NotSupportedException($"Bitmap (bbp {nbits}) color masks could not be determined, this usually indicates a malformed bitmap file.");
}
}
// The number of entries in the palette is either 2n (where n is the number of bits per pixel) or a smaller number specified in the header
// always allocate at least 256 entries so we can ignore bad data which seeks past the end of palette data.
var pallength = nbits < 16 ? (1 << nbits) : 0;
if (bi.bV5ClrUsed > 0)
{
pallength = (int)bi.bV5ClrUsed;
}
if (pallength > 256) // technically the max is 256..? some bitmaps have invalidly/absurdly large palettes
{
if (hasFileHeader)
{
// if we have a file header, we can correct our pixel data offset below, so the only
// important thing is that we don't read too many colors.
pallength = 256;
}
else
{
throw new NotSupportedException("Bitmap has an oversized/invalid color palette.");
}
}
RGBQUAD[] palette = new RGBQUAD[pallength];
var clrSize = is_os21x_ ? Marshal.SizeOf <RGBTRIPLE>() : Marshal.SizeOf <RGBQUAD>();
for (int i = 0; i < palette.Length; i++)
{
if (is_os21x_)
{
var small = StructUtil.Deserialize <RGBTRIPLE>(ptr);
palette[i] = new RGBQUAD {
rgbBlue = small.rgbBlue, rgbGreen = small.rgbGreen, rgbRed = small.rgbRed
};
}
else
{
palette[i] = StructUtil.Deserialize <RGBQUAD>(ptr);
}
ptr += clrSize;
}
offset += pallength * clrSize;
// For RGB DIBs, the image orientation is indicated by the biHeight member of the BITMAPINFOHEADER structure.
// If biHeight is positive, the image is bottom-up. If biHeight is negative, the image is top-down.
// DirectDraw uses top-down DIBs. In GDI, all DIBs are bottom-up.
// Also, any DIB type that uses a FOURCC in the biCompression member, should express its biHeight as a positive number
// no matter what its orientation is, since the FOURCC itself identifies a compression scheme whose image orientation
// should be understood by any compatible filter. Common YUV formats such as UYVY, YV12, and YUY2 are top-down oriented.
// It is invalid to store an image with these compression types in bottom-up orientation.
// The sign of biHeight for such formats must always be set positive
var width = bi.bV5Width;
var height = bi.bV5Height;
bool topDown = false;
if (height < 0)
{
height = -height;
topDown = true;
}
if (width < 0)
{
throw new NotSupportedException("Bitmap with negative width is not allowed");
}
uint source_stride = StructUtil.CalcStride(nbits, width);
uint dataOffset = hasFileHeader ? fh.bfOffBits : (uint)offset;
uint dataSize = bi.bV5SizeImage > 0 ? bi.bV5SizeImage : (source_stride * (uint)height);
if (dataOffset + dataSize > sourceLength)
{
throw new InvalidOperationException(ERR_HEOF);
}
var profileSize = bi.bV5ProfileSize;
uint profileOffset = (hasFileHeader ? (uint)size_fh : 0) + bi.bV5ProfileData;
if (profileOffset + profileSize > sourceLength)
{
throw new InvalidOperationException(ERR_HEOF);
}
var masks = new BITMASKS
{
maskRed = maskR,
maskGreen = maskG,
maskBlue = maskB,
maskAlpha = maskA,
};
var fmt = BitmapCorePixelFormat.Formats.SingleOrDefault(f => f.IsMatch(nbits, masks));
// currently we only support RLE -> Bgra32
if (bi.bV5Compression == BitmapCompressionMode.BI_RLE4 || bi.bV5Compression == BitmapCompressionMode.BI_RLE8 || bi.bV5Compression == BitmapCompressionMode.OS2_RLE24)
{
fmt = null;
}
double pixelPerMeterToDpi(int pels)
{
if (pels == 0)
{
return(96);
}
return(pels * 0.0254d);
}
mscms.SafeProfileHandle clrsource = null;
mscms.mscmsIntent clrintent = mscms.mscmsIntent.INTENT_PERCEPTUAL;
bool ignoreColorProfile = (bcrFlags & BC_READ_IGNORE_COLOR_PROFILE) > 0;
if (!ignoreColorProfile)
{
try
{
if (bi.bV5CSType == ColorSpaceType.LCS_CALIBRATED_RGB)
{
clrsource = mscms.CreateProfileFromLogicalColorSpace(bi);
}
else if (bi.bV5CSType == ColorSpaceType.PROFILE_EMBEDDED)
{
clrsource = mscms.OpenProfile((source + profileOffset), profileSize);
}
switch (bi.bV5Intent)
{
case Bv5Intent.LCS_GM_BUSINESS:
clrintent = mscms.mscmsIntent.INTENT_RELATIVE_COLORIMETRIC;
break;
case Bv5Intent.LCS_GM_GRAPHICS:
clrintent = mscms.mscmsIntent.INTENT_SATURATION;
break;
case Bv5Intent.LCS_GM_ABS_COLORIMETRIC:
clrintent = mscms.mscmsIntent.INTENT_ABSOLUTE_COLORIMETRIC;
break;
}
if (clrsource != null && fmt != null && fmt.MscmsFormat.HasValue && fmt.IsIndexed)
{
// transform color table if indexed image
palette = mscms.TransformColorsTo_sRGB(clrsource, palette, clrintent);
}
}
catch
{
// ignore color profile errors
}
}
info = new BITMAP_READ_DETAILS
{
dibHeader = bi,
bbp = nbits,
compression = bi.bV5Compression,
dpiX = pixelPerMeterToDpi(bi.bV5XPelsPerMeter),
dpiY = pixelPerMeterToDpi(bi.bV5YPelsPerMeter),
cMasks = masks,
cIndexed = smBit,
cTrueAlpha = hasAlphaChannel,
imgColorTable = palette,
imgHeight = height,
imgTopDown = topDown,
imgWidth = width,
imgDataOffset = dataOffset,
imgDataSize = dataSize,
imgStride = source_stride,
imgSourceFmt = fmt,
colorProfile = clrsource,
colorProfileIntent = clrintent,
};
}
public static void ReadIndexedTo32(ref BITMAP_READ_DETAILS info, byte *sourceBufferStart, byte *destBufferStart)
{
var palette = info.imgColorTable;
var nbits = info.bbp;
var width = info.imgWidth;
var height = info.imgHeight;
var upside_down = info.imgTopDown;
uint source_stride = StructUtil.CalcStride(nbits, width);
uint dest_stride = StructUtil.CalcStride(32, width);
RGBQUAD color;
int pal = palette.Length;
byte i4;
byte * source;
uint * dest;
int y, x, w, h = height, nbytes = (nbits / 8);
if (nbits == 1)
{
while (--h >= 0)
{
y = height - h - 1;
dest = (uint *)(destBufferStart + ((upside_down ? y : h) * dest_stride));
source = sourceBufferStart + (y * source_stride);
for (x = 0; x < source_stride - 1; x++)
{
i4 = *source++;
for (int bit = 7; bit >= 0; bit--)
{
color = palette[(i4 & (1 << bit)) >> bit];
*dest++ = (uint)((color.rgbBlue) | (color.rgbGreen << 8) | (color.rgbRed << 16) | (0xFF << 24));
}
}
// last bits in a row might not make up a whole byte
i4 = *source++;
for (int bit = 7; bit >= 8 - (width - ((source_stride - 1) * 8)); bit--)
{
color = palette[(i4 & (1 << bit)) >> bit];
*dest++ = (uint)((color.rgbBlue) | (color.rgbGreen << 8) | (color.rgbRed << 16) | (0xFF << 24));
}
}
}
else if (nbits == 2)
{
var px_remain = width % 4;
if (px_remain == 0)
{
px_remain = 4;
}
while (--h >= 0)
{
y = height - h - 1;
dest = (uint *)(destBufferStart + ((upside_down ? y : h) * dest_stride));
source = sourceBufferStart + (y * source_stride);
for (x = 0; x < source_stride - 1; x++)
{
i4 = *source++;
color = palette[((i4 & 0b_1100_0000) >> 6) % pal];
public static void ConvertChannelBGRA(ref BITMAP_READ_DETAILS info, BitmapCorePixelFormat convertToFmt, byte *sourceBufferStart, byte *destBufferStart, bool preserveFakeAlpha)
{
var nbits = info.bbp;
var width = info.imgWidth;
var height = info.imgHeight;
var upside_down = info.imgTopDown;
var hasAlphaChannel = info.cTrueAlpha;
var maskR = info.cMasks.maskRed;
var maskG = info.cMasks.maskGreen;
var maskB = info.cMasks.maskBlue;
var maskA = info.cMasks.maskAlpha;
int shiftR = 0, shiftG = 0, shiftB = 0, shiftA = 0;
uint maxR = 0, maxG = 0, maxB = 0, maxA = 0;
uint multR = 0, multG = 0, multB = 0, multA = 0;
if (maskR != 0)
{
shiftR = StructUtil.CalcShift(maskR);
maxR = maskR >> shiftR;
multR = (uint)(Math.Ceiling(255d / maxR * 65536 * 256)); // bitshift << 24
}
if (maskG != 0)
{
shiftG = StructUtil.CalcShift(maskG);
maxG = maskG >> shiftG;
multG = (uint)(Math.Ceiling(255d / maxG * 65536 * 256));
}
if (maskB != 0)
{
shiftB = StructUtil.CalcShift(maskB);
maxB = maskB >> shiftB;
multB = (uint)(Math.Ceiling(255d / maxB * 65536 * 256));
}
if (maskA != 0)
{
shiftA = StructUtil.CalcShift(maskA);
maxA = maskA >> shiftA;
multA = (uint)(Math.Ceiling(255d / maxA * 65536 * 256)); // bitshift << 24
}
var write = convertToFmt.Write;
uint source_stride = StructUtil.CalcStride(nbits, width);
uint dest_stride = StructUtil.CalcStride(convertToFmt.BitsPerPixel, width);
restartLoop:
byte b, r, g, a;
uint i32;
byte *source, dest;
int y, w, h = height, nbytes = (nbits / 8);
if (hasAlphaChannel)
{
while (--h >= 0)
{
y = height - h - 1;
dest = destBufferStart + ((upside_down ? y : h) * dest_stride);
source = sourceBufferStart + (y * source_stride);
w = width;
while (--w >= 0)
{
i32 = *(uint *)source;
b = (byte)((((i32 & maskB) >> shiftB) * multB) >> 24);
g = (byte)((((i32 & maskG) >> shiftG) * multG) >> 24);
r = (byte)((((i32 & maskR) >> shiftR) * multR) >> 24);
a = (byte)((((i32 & maskA) >> shiftA) * multA) >> 24);
dest = write(dest, b, g, r, a);
source += nbytes;
}
}
}
else if (maskA != 0 && preserveFakeAlpha) // hasAlpha = false, and maskA != 0 - we might have _fake_ alpha.. need to check for it
{
while (--h >= 0)
{
y = height - h - 1;
dest = destBufferStart + ((upside_down ? y : h) * dest_stride);
source = sourceBufferStart + (y * source_stride);
w = width;
while (--w >= 0)
{
i32 = *(uint *)source;
b = (byte)((((i32 & maskB) >> shiftB) * multB) >> 24);
g = (byte)((((i32 & maskG) >> shiftG) * multG) >> 24);
r = (byte)((((i32 & maskR) >> shiftR) * multR) >> 24);
a = (byte)((((i32 & maskA) >> shiftA) * multA) >> 24);
if (a != 0)
{
// this BMP should not have an alpha channel, but windows likes doing this and we need to detect it
hasAlphaChannel = true;
goto restartLoop;
}
dest = write(dest, b, g, r, 0xFF);
source += nbytes;
}
}
}
else // simple bmp, no transparency
{
while (--h >= 0)
{
y = height - h - 1;
dest = destBufferStart + ((upside_down ? y : h) * dest_stride);
source = sourceBufferStart + (y * source_stride);
w = width;
while (--w >= 0)
{
i32 = *(uint *)source;
b = (byte)((((i32 & maskB) >> shiftB) * multB) >> 24);
g = (byte)((((i32 & maskG) >> shiftG) * multG) >> 24);
r = (byte)((((i32 & maskR) >> shiftR) * multR) >> 24);
dest = write(dest, b, g, r, 0xFF);
source += nbytes;
}
}
}
}
public unsafe static BitmapSource Read(ref BITMAP_READ_DETAILS info, byte *pixels, uint bcrFlags)
{
// we do this parsing here since BitmapCore has no references to PresentationCore
if (info.compression == BitmapCompressionMode.BI_PNG)
{
var stream = new PointerStream(pixels, info.imgDataSize);
var png = new PngBitmapDecoder(stream, BitmapCreateOptions.None, BitmapCacheOption.OnLoad);
return(png.Frames[0]);
}
else if (info.compression == BitmapCompressionMode.BI_JPEG)
{
var stream = new PointerStream(pixels, info.imgDataSize);
var jpg = new JpegBitmapDecoder(stream, BitmapCreateOptions.None, BitmapCacheOption.OnLoad);
return(jpg.Frames[0]);
}
PixelFormat wpfFmt = PixelFormats.Bgra32;
BitmapCorePixelFormat coreFmt = BitmapCorePixelFormat.Bgra32;
bool forceBgra32 = (bcrFlags & BitmapCore.BC_READ_FORCE_BGRA32) > 0;
if (!forceBgra32 && info.imgSourceFmt != null)
{
var origFmt = info.imgSourceFmt;
var pxarr = Formats.Where(m => m.coreFmt == origFmt).ToArray();
if (pxarr.Length > 0)
{
var px = pxarr.First();
wpfFmt = px.wpfFmt;
coreFmt = px.coreFmt;
}
}
BitmapPalette palette = null;
if (info.imgColorTable.Length > 0)
{
var clrs = info.imgColorTable.Select(c => Color.FromRgb(c.rgbRed, c.rgbGreen, c.rgbBlue));
if (info.imgColorTable.Length > 256) // wpf throws on oversized palettes
{
clrs = clrs.Take(256);
}
palette = new BitmapPalette(clrs.ToList());
}
var bitmap = new WriteableBitmap(
info.imgWidth,
info.imgHeight,
info.dpiX,
info.dpiY,
wpfFmt,
palette);
var buf = (byte *)bitmap.BackBuffer;
bitmap.Lock();
BitmapCore.ReadPixels(ref info, coreFmt, pixels, buf, bcrFlags);
bitmap.AddDirtyRect(new System.Windows.Int32Rect(0, 0, info.imgWidth, info.imgHeight));
bitmap.Unlock();
bitmap.Freeze(); // dispose back buffer
return(bitmap);
}
