public ImportedImage ImportImage(StreamReaderHelper stream, PdfDocument document)
{
try
{
stream.CurrentOffset = 0;
int offsetImageData;
if (TestBitmapFileHeader(stream, out offsetImageData))
{
// Magic: TestBitmapFileHeader updates stream.CurrentOffset on success.
ImagePrivateDataBitmap ipd = new ImagePrivateDataBitmap(stream.Data, stream.Length);
ImportedImage ii = new ImportedImageBitmap(this, ipd, document);
if (TestBitmapInfoHeader(stream, ii, offsetImageData))
{
//stream.CurrentOffset = offsetImageData;
return(ii);
}
}
}
// ReSharper disable once EmptyGeneralCatchClause
catch (Exception)
{
}
return(null);
}
internal override ImageData PrepareImageData()
{
ImagePrivateDataBitmap data = (ImagePrivateDataBitmap)Data;
ImageDataBitmap imageData = new ImageDataBitmap(_document);
//imageData.Data = data.Data;
//imageData.Length = data.Length;
data.CopyBitmap(imageData);
return(imageData);
}
private bool TestBitmapInfoHeader(StreamReaderHelper stream, ImportedImage ii, int offset)
{
int size = (int)stream.GetDWord(0, false);
if (size == 40 || size == 108 || size == 124) // sizeof BITMAPINFOHEADER == 40, sizeof BITMAPV4HEADER == 108, sizeof BITMAPV5HEADER == 124
{
uint width = stream.GetDWord(4, false);
int height = (int)stream.GetDWord(8, false);
int planes = stream.GetWord(12, false);
int bitcount = stream.GetWord(14, false);
int compression = (int)stream.GetDWord(16, false);
int sizeImage = (int)stream.GetDWord(20, false);
int xPelsPerMeter = (int)stream.GetDWord(24, false);
int yPelsPerMeter = (int)stream.GetDWord(28, false);
uint colorsUsed = stream.GetDWord(32, false);
uint colorsImportant = stream.GetDWord(36, false);
// TODO Integrity and plausibility checks.
if (sizeImage != 0 && sizeImage + offset > stream.Length)
{
return(false);
}
ImagePrivateDataBitmap privateData = (ImagePrivateDataBitmap)ii.Data;
// Return true only for supported formats.
if (compression == 0 || compression == 3) // BI_RGB == 0, BI_BITFIELDS == 3
{
((ImagePrivateDataBitmap)ii.Data).Offset = offset;
((ImagePrivateDataBitmap)ii.Data).ColorPaletteOffset = stream.CurrentOffset + size;
ii.Information.Width = width;
ii.Information.Height = (uint)Math.Abs(height);
ii.Information.HorizontalDPM = xPelsPerMeter;
ii.Information.VerticalDPM = yPelsPerMeter;
privateData.FlippedImage = height < 0;
if (planes == 1 && bitcount == 24)
{
// RGB24
ii.Information.ImageFormat = ImageInformation.ImageFormats.RGB24;
// TODO: Verify Mask if size >= 108 && compression == 3.
return(true);
}
if (planes == 1 && bitcount == 32)
{
// ARGB32
//ii.Information.ImageFormat = ImageInformation.ImageFormats.ARGB32;
ii.Information.ImageFormat = compression == 0 ?
ImageInformation.ImageFormats.RGB24 :
ImageInformation.ImageFormats.ARGB32;
// TODO: tell RGB from ARGB. Idea: assume RGB if alpha is always 0.
// TODO: Verify Mask if size >= 108 && compression == 3.
return(true);
}
if (planes == 1 && bitcount == 8)
{
// Palette8
ii.Information.ImageFormat = ImageInformation.ImageFormats.Palette8;
ii.Information.ColorsUsed = colorsUsed;
return(true);
}
if (planes == 1 && bitcount == 4)
{
// Palette8
ii.Information.ImageFormat = ImageInformation.ImageFormats.Palette4;
ii.Information.ColorsUsed = colorsUsed;
return(true);
}
if (planes == 1 && bitcount == 1)
{
// Palette8
ii.Information.ImageFormat = ImageInformation.ImageFormats.Palette1;
ii.Information.ColorsUsed = colorsUsed;
return(true);
}
// TODO Implement more formats!
}
}
return(false);
}
/// <summary>
/// Initializes a new instance of the <see cref="ImportedImageBitmap"/> class.
/// </summary>
public ImportedImageBitmap(IImageImporter importer, ImagePrivateDataBitmap data, PdfDocument document)
: base(importer, data, document)
{
}