/// <summary>
/// Returns a string that represents the current object.
/// </summary>
/// <returns>Returns a string that represents the current object.</returns>
public override string ToString()
{
var sb = new StringBuilder();
sb.AppendFormat("IDLength : {0}\r\n", IDLength);
sb.AppendFormat("ColorMapType : {0}({1})\r\n", ColorMapType, ColorMapTypes.ToFormattedText(ColorMapType));
sb.AppendFormat("ImageType : {0}({1})\r\n", ImageType, ImageTypes.ToFormattedText(ImageType));
sb.AppendFormat("ColorMapStart : {0}\r\n", ColorMapStart);
sb.AppendFormat("ColorMapLength : {0}\r\n", ColorMapLength);
sb.AppendFormat("ColorMapDepth : {0}\r\n", ColorMapDepth);
sb.AppendFormat("XOffset : {0}\r\n", XOffset);
sb.AppendFormat("YOffset : {0}\r\n", YOffset);
sb.AppendFormat("Width : {0}\r\n", Width);
sb.AppendFormat("Height : {0}\r\n", Height);
sb.AppendFormat("PixelDepth : {0}\r\n", PixelDepth);
sb.AppendFormat("ImageDescriptor: 0x{0:X02}(attribute bits: {1}, image origin: {2})\r\n",
ImageDescriptor,
AttributeBits,
ImageOriginTypes.ToFormattedText(ImageOrigin));
return(sb.ToString());
}
/// <summary>
/// Read an image data.
/// </summary>
/// <param name="reader">A binary reader that contains TGA file. Caller must dipose the binary reader.</param>
private void ReadImageBytes(BinaryReader reader)
{
switch (Header.ImageType)
{
case ImageTypes.ColorMapped:
case ImageTypes.TrueColor:
case ImageTypes.Monochrome:
ReadUncompressedData(reader);
break;
case ImageTypes.CompressedColorMapped:
case ImageTypes.CompressedTrueColor:
case ImageTypes.CompressedMonochrome:
DecodeRunLengthEncoding(reader);
break;
default:
throw new NotSupportedException(
string.Format("Image type \"{0}({1})\" isn't supported.", Header.ImageType, ImageTypes.ToFormattedText(Header.ImageType)));
}
}
/// <summary>
/// Extracts a pixel data.
/// </summary>
/// <param name="rawPixelData">A raw pixel data in the TGA file.</param>
/// <returns>
/// Returns a pixel data in the palette, if an image type is color-mapped.
/// Returns a raw pixel data, if an image type is RGB or grayscale.
/// </returns>
private byte[] ExtractPixelData(byte[] rawPixelData)
{
byte[] pixelData = null;
switch (Header.ImageType)
{
case ImageTypes.ColorMapped:
case ImageTypes.CompressedColorMapped:
{
// Extracts a pixel data in the palette.
var paletteIndex = GetPaletteIndex(rawPixelData);
var bytesPerPixel = GetBytesPerPixel();
var realPixelData = new byte[bytesPerPixel];
Array.Copy(ColorMap,
(Header.ColorMapStart + paletteIndex) * bytesPerPixel,
realPixelData,
0,
realPixelData.Length);
pixelData = realPixelData;
}
break;
case ImageTypes.TrueColor:
case ImageTypes.Monochrome:
case ImageTypes.CompressedTrueColor:
case ImageTypes.CompressedMonochrome:
// Returns a raw pixel data as is.
pixelData = rawPixelData;
break;
default:
throw new NotSupportedException(
string.Format("Image type \"{0}({1})\" isn't supported.", Header.ImageType, ImageTypes.ToFormattedText(Header.ImageType)));
}
if (!HasAlpha() && !useAlphaChannelForcefully_ && (GetPixelFormat() == PixelFormats.Bgra32))
{
pixelData[ArgbOffset.Alpha] = 0xFF;
}
return(pixelData);
}
/// <summary>
/// Gets a pixel format of TGA image.
/// </summary>
/// <returns>Returns a pixel format of TGA image.</returns>
private PixelFormat GetPixelFormat()
{
switch (Header.ImageType)
{
case ImageTypes.ColorMapped:
case ImageTypes.CompressedColorMapped:
{
// color depth of color-mapped image is defined in the palette
switch (Header.ColorMapDepth)
{
case ColorDepth.Bpp15:
case ColorDepth.Bpp16:
return(PixelFormats.Bgr555);
case ColorDepth.Bpp24:
return(PixelFormats.Bgr24);
case ColorDepth.Bpp32:
return(PixelFormats.Bgra32);
default:
throw new NotSupportedException(string.Format("Color depth isn't supported({0}bpp).", Header.ColorMapDepth));
}
}
case ImageTypes.TrueColor:
case ImageTypes.CompressedTrueColor:
{
switch (Header.PixelDepth)
{
case ColorDepth.Bpp15:
case ColorDepth.Bpp16:
return(PixelFormats.Bgr555);
case ColorDepth.Bpp24:
return(PixelFormats.Bgr24);
case ColorDepth.Bpp32:
return(PixelFormats.Bgra32);
default:
throw new NotSupportedException(string.Format("Color depth isn't supported({0}bpp).", Header.PixelDepth));
}
}
case ImageTypes.Monochrome:
case ImageTypes.CompressedMonochrome:
{
switch (Header.PixelDepth)
{
case ColorDepth.Bpp8:
return(PixelFormats.Gray8);
default:
throw new NotSupportedException(string.Format("Color depth isn't supported({0}bpp).", Header.PixelDepth));
}
}
default:
throw new NotSupportedException(
string.Format("Image type \"{0}({1})\" isn't supported.", Header.ImageType, ImageTypes.ToFormattedText(Header.ImageType)));
}
}
