/// <inheritdoc/>
public Task <IImageInfo> IdentifyAsync(Configuration configuration, Stream stream, CancellationToken cancellationToken)
{
Guard.NotNull(stream, nameof(stream));
var decoder = new TiffDecoderCore(configuration, this);
return(decoder.IdentifyAsync(configuration, stream, cancellationToken));
}
/// <inheritdoc/>
public IImageInfo Identify(Configuration configuration, Stream stream)
{
Guard.NotNull(stream, nameof(stream));
var decoder = new TiffDecoderCore(configuration, this);
return(decoder.Identify(configuration, stream));
}
/// <inheritdoc/>
public Task <Image <TPixel> > DecodeAsync <TPixel>(Configuration configuration, Stream stream, CancellationToken cancellationToken)
where TPixel : unmanaged, IPixel <TPixel>
{
Guard.NotNull(stream, nameof(stream));
var decoder = new TiffDecoderCore(configuration, this);
return(decoder.DecodeAsync <TPixel>(configuration, stream, cancellationToken));
}
/// <inheritdoc/>
public Image <TPixel> Decode <TPixel>(Configuration configuration, Stream stream)
where TPixel : unmanaged, IPixel <TPixel>
{
Guard.NotNull(stream, "stream");
var decoder = new TiffDecoderCore(configuration, this);
return(decoder.Decode <TPixel>(configuration, stream));
}
private static void ParseCompression(this TiffDecoderCore options, TiffCompression?compression, ExifProfile exifProfile)
{
// Default 1 (No compression) https://www.awaresystems.be/imaging/tiff/tifftags/compression.html
switch (compression ?? TiffCompression.None)
{
case TiffCompression.None:
{
options.CompressionType = TiffDecoderCompressionType.None;
break;
}
case TiffCompression.PackBits:
{
options.CompressionType = TiffDecoderCompressionType.PackBits;
break;
}
case TiffCompression.Deflate:
case TiffCompression.OldDeflate:
{
options.CompressionType = TiffDecoderCompressionType.Deflate;
break;
}
case TiffCompression.Lzw:
{
options.CompressionType = TiffDecoderCompressionType.Lzw;
break;
}
case TiffCompression.CcittGroup3Fax:
{
options.CompressionType = TiffDecoderCompressionType.T4;
options.FaxCompressionOptions = exifProfile.GetValue(ExifTag.T4Options) != null ? (FaxCompressionOptions)exifProfile.GetValue(ExifTag.T4Options).Value : FaxCompressionOptions.None;
break;
}
case TiffCompression.CcittGroup4Fax:
{
options.CompressionType = TiffDecoderCompressionType.T6;
options.FaxCompressionOptions = exifProfile.GetValue(ExifTag.T4Options) != null ? (FaxCompressionOptions)exifProfile.GetValue(ExifTag.T4Options).Value : FaxCompressionOptions.None;
break;
}
case TiffCompression.Ccitt1D:
{
options.CompressionType = TiffDecoderCompressionType.HuffmanRle;
break;
}
case TiffCompression.Jpeg:
{
options.CompressionType = TiffDecoderCompressionType.Jpeg;
break;
}
default:
{
TiffThrowHelper.ThrowNotSupported($"The specified TIFF compression format '{compression}' is not supported");
break;
}
}
}
/// <summary>
/// Determines the TIFF compression and color types, and reads any associated parameters.
/// </summary>
/// <param name="options">The options.</param>
/// <param name="exifProfile">The exif profile of the frame to decode.</param>
/// <param name="frameMetadata">The IFD entries container to read the image format information for current frame.</param>
public static void VerifyAndParse(this TiffDecoderCore options, ExifProfile exifProfile, TiffFrameMetadata frameMetadata)
{
if (exifProfile.GetValueInternal(ExifTag.TileOffsets) is not null || exifProfile.GetValueInternal(ExifTag.TileByteCounts) is not null)
{
TiffThrowHelper.ThrowNotSupported("Tiled images are not supported.");
}
if (exifProfile.GetValueInternal(ExifTag.ExtraSamples) is not null)
{
TiffThrowHelper.ThrowNotSupported("ExtraSamples is not supported.");
}
TiffFillOrder fillOrder = (TiffFillOrder?)exifProfile.GetValue(ExifTag.FillOrder)?.Value ?? TiffFillOrder.MostSignificantBitFirst;
if (fillOrder == TiffFillOrder.LeastSignificantBitFirst && frameMetadata.BitsPerPixel != TiffBitsPerPixel.Bit1)
{
TiffThrowHelper.ThrowNotSupported("The lower-order bits of the byte FillOrder is only supported in combination with 1bit per pixel bicolor tiff's.");
}
if (frameMetadata.Predictor == TiffPredictor.FloatingPoint)
{
TiffThrowHelper.ThrowNotSupported("TIFF images with FloatingPoint horizontal predictor are not supported.");
}
TiffSampleFormat[] sampleFormats = exifProfile.GetValue(ExifTag.SampleFormat)?.Value?.Select(a => (TiffSampleFormat)a).ToArray();
TiffSampleFormat? sampleFormat = null;
if (sampleFormats != null)
{
sampleFormat = sampleFormats[0];
foreach (TiffSampleFormat format in sampleFormats)
{
if (format != TiffSampleFormat.UnsignedInteger && format != TiffSampleFormat.Float)
{
TiffThrowHelper.ThrowNotSupported("ImageSharp only supports the UnsignedInteger and Float SampleFormat.");
}
}
}
ushort[] ycbcrSubSampling = exifProfile.GetValue(ExifTag.YCbCrSubsampling)?.Value;
if (ycbcrSubSampling != null && ycbcrSubSampling.Length != 2)
{
TiffThrowHelper.ThrowImageFormatException("Invalid YCbCrSubsampling, expected 2 values.");
}
if (ycbcrSubSampling != null && ycbcrSubSampling[1] > ycbcrSubSampling[0])
{
TiffThrowHelper.ThrowImageFormatException("ChromaSubsampleVert shall always be less than or equal to ChromaSubsampleHoriz.");
}
if (exifProfile.GetValue(ExifTag.StripRowCounts)?.Value != null)
{
TiffThrowHelper.ThrowNotSupported("Variable-sized strips are not supported.");
}
VerifyRequiredFieldsArePresent(exifProfile, frameMetadata);
options.PlanarConfiguration = (TiffPlanarConfiguration?)exifProfile.GetValue(ExifTag.PlanarConfiguration)?.Value ?? DefaultPlanarConfiguration;
options.Predictor = frameMetadata.Predictor ?? TiffPredictor.None;
options.PhotometricInterpretation = frameMetadata.PhotometricInterpretation ?? TiffPhotometricInterpretation.Rgb;
options.SampleFormat = sampleFormat ?? TiffSampleFormat.UnsignedInteger;
options.BitsPerPixel = frameMetadata.BitsPerPixel != null ? (int)frameMetadata.BitsPerPixel.Value : (int)TiffBitsPerPixel.Bit24;
options.BitsPerSample = frameMetadata.BitsPerSample ?? new TiffBitsPerSample(0, 0, 0);
options.ReferenceBlackAndWhite = exifProfile.GetValue(ExifTag.ReferenceBlackWhite)?.Value;
options.YcbcrCoefficients = exifProfile.GetValue(ExifTag.YCbCrCoefficients)?.Value;
options.YcbcrSubSampling = exifProfile.GetValue(ExifTag.YCbCrSubsampling)?.Value;
options.FillOrder = fillOrder;
options.JpegTables = exifProfile.GetValue(ExifTag.JPEGTables)?.Value;
options.ParseColorType(exifProfile);
options.ParseCompression(frameMetadata.Compression, exifProfile);
}
private static void ParseColorType(this TiffDecoderCore options, ExifProfile exifProfile)
{
switch (options.PhotometricInterpretation)
{
case TiffPhotometricInterpretation.WhiteIsZero:
{
if (options.BitsPerSample.Channels != 1)
{
TiffThrowHelper.ThrowNotSupported("The number of samples in the TIFF BitsPerSample entry is not supported.");
}
ushort bitsPerChannel = options.BitsPerSample.Channel0;
if (bitsPerChannel > 32)
{
TiffThrowHelper.ThrowNotSupported("Bits per sample is not supported.");
}
switch (bitsPerChannel)
{
case 32:
{
if (options.SampleFormat == TiffSampleFormat.Float)
{
options.ColorType = TiffColorType.WhiteIsZero32Float;
return;
}
options.ColorType = TiffColorType.WhiteIsZero32;
break;
}
case 24:
{
options.ColorType = TiffColorType.WhiteIsZero24;
break;
}
case 16:
{
options.ColorType = TiffColorType.WhiteIsZero16;
break;
}
case 8:
{
options.ColorType = TiffColorType.WhiteIsZero8;
break;
}
case 4:
{
options.ColorType = TiffColorType.WhiteIsZero4;
break;
}
case 1:
{
options.ColorType = TiffColorType.WhiteIsZero1;
break;
}
default:
{
options.ColorType = TiffColorType.WhiteIsZero;
break;
}
}
break;
}
case TiffPhotometricInterpretation.BlackIsZero:
{
if (options.BitsPerSample.Channels != 1)
{
TiffThrowHelper.ThrowNotSupported("The number of samples in the TIFF BitsPerSample entry is not supported.");
}
ushort bitsPerChannel = options.BitsPerSample.Channel0;
if (bitsPerChannel > 32)
{
TiffThrowHelper.ThrowNotSupported("Bits per sample is not supported.");
}
switch (bitsPerChannel)
{
case 32:
{
if (options.SampleFormat == TiffSampleFormat.Float)
{
options.ColorType = TiffColorType.BlackIsZero32Float;
return;
}
options.ColorType = TiffColorType.BlackIsZero32;
break;
}
case 24:
{
options.ColorType = TiffColorType.BlackIsZero24;
break;
}
case 16:
{
options.ColorType = TiffColorType.BlackIsZero16;
break;
}
case 8:
{
options.ColorType = TiffColorType.BlackIsZero8;
break;
}
case 4:
{
options.ColorType = TiffColorType.BlackIsZero4;
break;
}
case 1:
{
options.ColorType = TiffColorType.BlackIsZero1;
break;
}
default:
{
options.ColorType = TiffColorType.BlackIsZero;
break;
}
}
break;
}
case TiffPhotometricInterpretation.Rgb:
{
TiffBitsPerSample bitsPerSample = options.BitsPerSample;
if (bitsPerSample.Channels != 3)
{
TiffThrowHelper.ThrowNotSupported("The number of samples in the TIFF BitsPerSample entry is not supported.");
}
if (!(bitsPerSample.Channel0 == bitsPerSample.Channel1 && bitsPerSample.Channel1 == bitsPerSample.Channel2))
{
TiffThrowHelper.ThrowNotSupported("Only BitsPerSample with equal bits per channel are supported.");
}
if (options.PlanarConfiguration == TiffPlanarConfiguration.Chunky)
{
ushort bitsPerChannel = options.BitsPerSample.Channel0;
switch (bitsPerChannel)
{
case 32:
if (options.SampleFormat == TiffSampleFormat.Float)
{
options.ColorType = TiffColorType.RgbFloat323232;
return;
}
options.ColorType = TiffColorType.Rgb323232;
break;
case 24:
options.ColorType = TiffColorType.Rgb242424;
break;
case 16:
options.ColorType = TiffColorType.Rgb161616;
break;
case 14:
options.ColorType = TiffColorType.Rgb141414;
break;
case 12:
options.ColorType = TiffColorType.Rgb121212;
break;
case 10:
options.ColorType = TiffColorType.Rgb101010;
break;
case 8:
options.ColorType = TiffColorType.Rgb888;
break;
case 4:
options.ColorType = TiffColorType.Rgb444;
break;
case 2:
options.ColorType = TiffColorType.Rgb222;
break;
default:
TiffThrowHelper.ThrowNotSupported("Bits per sample is not supported.");
break;
}
}
else
{
ushort bitsPerChannel = options.BitsPerSample.Channel0;
switch (bitsPerChannel)
{
case 32:
options.ColorType = TiffColorType.Rgb323232Planar;
break;
case 24:
options.ColorType = TiffColorType.Rgb242424Planar;
break;
case 16:
options.ColorType = TiffColorType.Rgb161616Planar;
break;
default:
options.ColorType = TiffColorType.Rgb888Planar;
break;
}
}
break;
}
case TiffPhotometricInterpretation.PaletteColor:
{
options.ColorMap = exifProfile.GetValue(ExifTag.ColorMap)?.Value;
if (options.ColorMap != null)
{
if (options.BitsPerSample.Channels != 1)
{
TiffThrowHelper.ThrowNotSupported("The number of samples in the TIFF BitsPerSample entry is not supported.");
}
options.ColorType = TiffColorType.PaletteColor;
}
else
{
TiffThrowHelper.ThrowNotSupported("The TIFF ColorMap entry is missing for a palette color image.");
}
break;
}
case TiffPhotometricInterpretation.YCbCr:
{
options.ColorMap = exifProfile.GetValue(ExifTag.ColorMap)?.Value;
if (options.BitsPerSample.Channels != 3)
{
TiffThrowHelper.ThrowNotSupported("The number of samples in the TIFF BitsPerSample entry is not supported.");
}
ushort bitsPerChannel = options.BitsPerSample.Channel0;
if (bitsPerChannel != 8)
{
TiffThrowHelper.ThrowNotSupported("Only 8 bits per channel is supported for YCbCr images.");
}
options.ColorType = options.PlanarConfiguration == TiffPlanarConfiguration.Chunky ? TiffColorType.YCbCr : TiffColorType.YCbCrPlanar;
break;
}
default:
{
TiffThrowHelper.ThrowNotSupported($"The specified TIFF photometric interpretation is not supported: {options.PhotometricInterpretation}");
}
break;
}
}