private static EditableImage ReadPaletteBmp(byte[] buffer, Color[] palette, BmpInfoHeader header, int bpp)
{
int ppb = 8 / bpp; // Pixels per byte (bits per pixel)
int width = (header.Width + ppb - 1) / ppb;
int alignment = width % 4; // Rows are aligned on 4 byte boundaries
int mask = (0xFF >> (8 - bpp)); // Bit mask
int rowbase;
int colbase;
int offset;
int realRow;
Color color;
EditableImage image = new EditableImage(header.Width, header.Height);
if (alignment != 0)
{
alignment = 4 - alignment; // Calculate row padding
}
for (int row = 0; row < header.Height; row++)
{
rowbase = (row * (width + alignment));
for (int col = 0; col < width; col++)
{
offset = rowbase + col;
colbase = col * ppb;
realRow = header.Height - row - 1; // Reverse row
for (int shift = 0; ((shift < ppb) && ((colbase + shift) < header.Width)); shift++)
{
color = palette[((buffer[offset]) >> (8 - bpp - (shift * bpp))) & mask];
image.SetPixel(colbase + shift, realRow, color.R, color.G, color.B, 255);
}
}
}
return image;
}
private static EditableImage Read8BitBmp(byte[] buffer, Color[] palette, BmpInfoHeader header)
{
int alignment = header.Width % 4; // Rows are aligned on 4 byte boundaries
int rowbase = 0;
int offset;
int realRow;
Color color;
EditableImage image = new EditableImage(header.Width, header.Height);
if (alignment != 0)
{
alignment = 4 - alignment; // Calculate row padding
}
for (int row = 0; row < header.Height; row++)
{
rowbase = (row * (header.Width + alignment));
for (int col = 0; col < header.Width; col++)
{
offset = rowbase + col;
realRow = header.Height - row - 1; // Reverse row
color = palette[buffer[offset]];
image.SetPixel(col, realRow, color.R, color.G, color.B, color.A);
}
}
return image;
}
private static EditableImage Read565Bmp(byte[] buffer, BmpInfoHeader header)
{
int rowbase = 0;
int offset;
int realRow;
short color;
byte red;
byte green;
byte blue;
int scaleR = 256 / 32;
int scaleG = 256 / 64;
EditableImage image = new EditableImage(header.Width, header.Height);
for (int row = 0; row < header.Height; row++)
{
rowbase = (row * header.Width * 2);
for (int col = 0; col < header.Width; col++)
{
offset = rowbase + (col * 2);
realRow = header.Height - row - 1; // Reverse row
// Get color and convert
color = BitConverter.ToInt16(buffer, offset);
red = (byte)(((color & _REDMASK) >> 11) * scaleR);
green = (byte)(((color & _GREENMASK) >> 5) * scaleG);
blue = (byte)(((color & _BLUEMASK)) * scaleR);
// Set pixel
image.SetPixel(col, realRow, red, green, blue, 255);
}
}
return image;
}
private static EditableImage Read4BitBmp(byte[] buffer, Color[] palette, BmpInfoHeader header)
{
int width = (header.Width + 1) / 2;
int alignment = width % 4; // Rows are aligned on 4 byte boundaries
int rowbase = 0;
int colbase = 0;
int offset;
int realRow;
Color color1;
Color color2;
EditableImage image = new EditableImage(header.Width, header.Height);
if (alignment != 0)
{
alignment = 4 - alignment; // Calculate row padding
}
for (int row = 0; row < header.Height; row++)
{
rowbase = (row * (width + alignment));
for (int col = 0; col < width; col++)
{
colbase = col * 2;
offset = rowbase + col;
realRow = header.Height - row - 1; // Reverse row
color1 = palette[(buffer[offset]) >> 4];
color2 = palette[(buffer[offset]) & 0x0F];
image.SetPixel(colbase, realRow, color1.R, color1.G, color1.B, 255);
image.SetPixel(colbase + 1, realRow, color2.R, color2.G, color2.B, 255);
}
}
return image;
}
private static EditableImage Read24BitBmp(byte[] buffer, BmpInfoHeader header)
{
int alignment = (header.Width * 3) % 4; // Rows are aligned on 4 byte boundaries
int rowbase = 0;
int offset;
int realRow;
EditableImage image = new EditableImage(header.Width, header.Height);
if (alignment != 0)
{
alignment = 4 - alignment; // Calculate row padding
}
for (int row = 0; row < header.Height; row++)
{
rowbase = (row * ((header.Width * 3) + alignment));
for (int col = 0; col < header.Width; col++)
{
offset = rowbase + (col * 3);
realRow = header.Height - row - 1; // Reverse row
if (offset >= buffer.Length)
{
HtmlPage.Window.Alert("Error - outside of bounds and not sure why");
}
image.SetPixel(col, realRow, buffer[offset + 2], buffer[offset + 1], buffer[offset], 255);
}
}
return image;
}
/// <summary>
///
/// </summary>
/// <param name="stream"></param>
/// <returns></returns>
public static BmpInfoHeader FillFromStream(Stream stream)
{
byte[] buffer = new byte[_SIZE];
BmpInfoHeader header = new BmpInfoHeader();
stream.Read(buffer, 0, _SIZE);
// Fill
header.HeaderSize = BitConverter.ToInt32(buffer, 0);
header.Width = BitConverter.ToInt32(buffer, 4);
header.Height = BitConverter.ToInt32(buffer, 8);
header.BitsPerPixel = BitConverter.ToInt16(buffer, 14);
header.Compression = BitConverter.ToInt32(buffer, 16);
header.ImageSize = BitConverter.ToInt32(buffer, 20);
header.ColorCount = BitConverter.ToInt32(buffer, 32);
// Fix for no ImageSize in the header
if (header.ImageSize == 0)
{
int rowSize = 4 * (int)Math.Ceiling(header.Width * (header.BitsPerPixel / 32));
int fileSize = header.HeaderSize + (4 * (int)Math.Pow(2, header.BitsPerPixel)) + rowSize + header.Height;
header.ImageSize = (int)fileSize;
}
if (header.ColorCount == 0)
{
header.ColorCount = (1 << header.BitsPerPixel);
}
// Return results
return header;
}
