/// <summary>
/// Decodes the image data from a specified IFD.
/// </summary>
/// <typeparam name="TPixel">The pixel format.</typeparam>
/// <param name="tags">The IFD tags.</param>
/// <param name="cancellationToken">The token to monitor cancellation.</param>
/// <returns> The tiff frame. </returns>
private ImageFrame <TPixel> DecodeFrame <TPixel>(ExifProfile tags, CancellationToken cancellationToken)
where TPixel : unmanaged, IPixel <TPixel>
{
var imageFrameMetaData = new ImageFrameMetadata();
if (!this.ignoreMetadata)
{
imageFrameMetaData.ExifProfile = tags;
}
TiffFrameMetadata tiffFrameMetaData = imageFrameMetaData.GetTiffMetadata();
TiffFrameMetadata.Parse(tiffFrameMetaData, tags);
this.VerifyAndParse(tags, tiffFrameMetaData);
int width = GetImageWidth(tags);
int height = GetImageHeight(tags);
var frame = new ImageFrame <TPixel>(this.Configuration, width, height, imageFrameMetaData);
int rowsPerStrip = tags.GetValue(ExifTag.RowsPerStrip) != null ? (int)tags.GetValue(ExifTag.RowsPerStrip).Value : TiffConstants.RowsPerStripInfinity;
var stripOffsetsArray = (Array)tags.GetValueInternal(ExifTag.StripOffsets).GetValue();
var stripByteCountsArray = (Array)tags.GetValueInternal(ExifTag.StripByteCounts).GetValue();
IMemoryOwner <ulong> stripOffsetsMemory = this.ConvertNumbers(stripOffsetsArray, out Span <ulong> stripOffsets);
IMemoryOwner <ulong> stripByteCountsMemory = this.ConvertNumbers(stripByteCountsArray, out Span <ulong> stripByteCounts);
if (this.PlanarConfiguration == TiffPlanarConfiguration.Planar)
{
this.DecodeStripsPlanar(
frame,
rowsPerStrip,
stripOffsets,
stripByteCounts,
cancellationToken);
}
else
{
this.DecodeStripsChunky(
frame,
rowsPerStrip,
stripOffsets,
stripByteCounts,
cancellationToken);
}
stripOffsetsMemory?.Dispose();
stripByteCountsMemory?.Dispose();
return(frame);
}
private static void VerifyRequiredFieldsArePresent(ExifProfile exifProfile, TiffFrameMetadata frameMetadata)
{
if (exifProfile.GetValueInternal(ExifTag.StripOffsets) is null)
{
TiffThrowHelper.ThrowImageFormatException("StripOffsets are missing and are required for decoding the TIFF image!");
}
if (exifProfile.GetValueInternal(ExifTag.StripByteCounts) is null)
{
TiffThrowHelper.ThrowImageFormatException("StripByteCounts are missing and are required for decoding the TIFF image!");
}
if (frameMetadata.BitsPerPixel == null)
{
TiffThrowHelper.ThrowNotSupported("The TIFF BitsPerSample entry is missing which is required to decode the image!");
}
}
public void DamagedFiles <TPixel>(TestImageProvider <TPixel> provider)
where TPixel : unmanaged, IPixel <TPixel>
{
Assert.Throws <ImageDifferenceIsOverThresholdException>(() => TestTiffDecoder(provider));
using Image <TPixel> image = provider.GetImage(TiffDecoder);
ExifProfile exif = image.Frames.RootFrame.Metadata.ExifProfile;
// PhotometricInterpretation is required tag: https://www.awaresystems.be/imaging/tiff/tifftags/photometricinterpretation.html
Assert.Null(exif.GetValueInternal(ExifTag.PhotometricInterpretation));
}
public void WritingImagePreservesExifProfile(TestImageWriteFormat imageFormat)
{
// Arrange
var image = new Image <Rgba32>(1, 1);
image.Metadata.ExifProfile = CreateExifProfile();
// Act
Image <Rgba32> reloadedImage = WriteAndRead(image, imageFormat);
// Assert
ExifProfile actual = reloadedImage.Metadata.ExifProfile;
Assert.NotNull(actual);
foreach (KeyValuePair <ExifTag, object> expectedProfileValue in TestProfileValues)
{
IExifValue actualProfileValue = actual.GetValueInternal(expectedProfileValue.Key);
Assert.NotNull(actualProfileValue);
Assert.Equal(expectedProfileValue.Value, actualProfileValue.GetValue());
}
}
public void ProfileToByteArray()
{
// Arrange
byte[] exifBytesWithoutExifCode = ExifConstants.LittleEndianByteOrderMarker;
ExifProfile expectedProfile = CreateExifProfile();
var expectedProfileTags = expectedProfile.Values.Select(x => x.Tag).ToList();
// Act
byte[] actualBytes = expectedProfile.ToByteArray();
var actualProfile = new ExifProfile(actualBytes);
// Assert
Assert.NotNull(actualBytes);
Assert.NotEmpty(actualBytes);
Assert.Equal(exifBytesWithoutExifCode, actualBytes.Take(exifBytesWithoutExifCode.Length).ToArray());
foreach (ExifTag expectedProfileTag in expectedProfileTags)
{
IExifValue actualProfileValue = actualProfile.GetValueInternal(expectedProfileTag);
IExifValue expectedProfileValue = expectedProfile.GetValueInternal(expectedProfileTag);
Assert.Equal(expectedProfileValue.GetValue(), actualProfileValue.GetValue());
}
}
public void ReadWriteLargeProfileJpg()
{
ExifTag <string>[] tags = new[] { ExifTag.Software, ExifTag.Copyright, ExifTag.Model, ExifTag.ImageDescription };
foreach (ExifTag <string> tag in tags)
{
// Arrange
var junk = new StringBuilder();
for (int i = 0; i < 65600; i++)
{
junk.Append("a");
}
var image = new Image <Rgba32>(100, 100);
ExifProfile expectedProfile = CreateExifProfile();
var expectedProfileTags = expectedProfile.Values.Select(x => x.Tag).ToList();
expectedProfile.SetValue(tag, junk.ToString());
image.Metadata.ExifProfile = expectedProfile;
// Act
Image <Rgba32> reloadedImage = WriteAndRead(image, TestImageWriteFormat.Jpeg);
// Assert
ExifProfile actualProfile = reloadedImage.Metadata.ExifProfile;
Assert.NotNull(actualProfile);
foreach (ExifTag expectedProfileTag in expectedProfileTags)
{
IExifValue actualProfileValue = actualProfile.GetValueInternal(expectedProfileTag);
IExifValue expectedProfileValue = expectedProfile.GetValueInternal(expectedProfileTag);
Assert.Equal(expectedProfileValue.GetValue(), actualProfileValue.GetValue());
}
IExifValue <string> expected = expectedProfile.GetValue(tag);
IExifValue <string> actual = actualProfile.GetValue(tag);
Assert.Equal(expected, actual);
}
}
/// <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);
}
