private static Image LoadUncompressedTrueColorImage(BinaryReader fileStream, TgaHeader header)
{
if (header.depth == 24)
{
var img = new Image();
img.width = header.width;
img.height = header.height;
img.pitch = (ushort)(img.width * 3);
img.Format = ImageFormat.RGB_888;
img.data = new byte[img.height * img.pitch];
int pos = 0;
while (pos < img.data.Length)
{
var len = fileStream.Read(img.data, pos, img.data.Length - pos);
if (len <= 0)
{
break;
}
pos += len;
}
if ((header.descriptor & 0x20) == 0)
{
img.FlipVerticaly();
}
return img;
}
else if (header.depth == 32)
{
var img = new Image();
img.width = header.width;
img.height = header.height;
img.pitch = (ushort)(img.width * 4);
img.Format = ImageFormat.ABGR_8888;
img.data = new byte[img.height * img.pitch];
int pos = 0;
while (pos < img.data.Length)
{
var len = fileStream.Read(img.data, pos, img.data.Length - pos);
if (len <= 0)
{
break;
}
pos += len;
}
if ((header.descriptor & 0x20) == 0)
{
img.FlipVerticaly();
}
for (int i = 0; i < img.data.Length; i += 4)
{
byte b = img.data[i];
img.data[i] = img.data[i + 2];
img.data[i + 2] = b;
}
return img;
}
throw new FormatException();
}
private static Image LoadTGA(string filePath)
{
using (var fileStream = new BinaryReader(File.OpenRead(filePath)))
{
TgaHeader header = new TgaHeader();
header.imageIDLength = fileStream.ReadByte();
header.colorMapType = fileStream.ReadByte();
header.imageType = fileStream.ReadByte();
header.firstEntryIndex = fileStream.ReadUInt16();
header.colorMapLength = fileStream.ReadUInt16();
header.colorMapEntrySize = fileStream.ReadByte();
header.xOrigin = fileStream.ReadUInt16();
//absolute coordinate of lower-left corner for displays where origin is at the lower left
header.yOrigin = fileStream.ReadUInt16(); //as for X-origin
header.width = fileStream.ReadUInt16();
header.height = fileStream.ReadUInt16();
header.depth = fileStream.ReadByte();
header.descriptor = fileStream.ReadByte();
if (header.colorMapType != 0)
{
throw new FormatException("image file contains color map");
}
if (header.imageType == 2)
{
return LoadUncompressedTrueColorImage(fileStream, header);
}
throw new FormatException("Only uncompressed true-color image supported");
}
}