public void TestGetComponentDescription() { var component1 = new JpegComponent(1, 0x22, 0); _directory.Set(JpegDirectory.TagComponentData1, component1); Assert.Equal("Y component: Quantization table 0, Sampling factors 2 horiz/2 vert", _directory.GetDescription(JpegDirectory.TagComponentData1)); Assert.Equal("Y component: Quantization table 0, Sampling factors 2 horiz/2 vert", _descriptor.GetComponentDataDescription(0)); }
public void TestGetComponent() { var component1 = new JpegComponent(1, 2, 3); var component2 = new JpegComponent(1, 2, 3); var component3 = new JpegComponent(1, 2, 3); var component4 = new JpegComponent(1, 2, 3); _directory.Set(JpegDirectory.TagComponentData1, component1); _directory.Set(JpegDirectory.TagComponentData2, component2); _directory.Set(JpegDirectory.TagComponentData3, component3); _directory.Set(JpegDirectory.TagComponentData4, component4); // component numbers are zero-indexed for this method Assert.Same(component1, _directory.GetComponent(0)); Assert.Same(component2, _directory.GetComponent(1)); Assert.Same(component3, _directory.GetComponent(2)); Assert.Same(component4, _directory.GetComponent(3)); }
/// <summary>Reads JPEG SOF values and returns them in a <see cref="JpegDirectory"/>.</summary> public JpegDirectory Extract(JpegSegment segment) { var directory = new JpegDirectory(); // The value of TagCompressionType is determined by the segment type found directory.Set(JpegDirectory.TagCompressionType, (int)segment.Type - (int)JpegSegmentType.Sof0); SequentialReader reader = new SequentialByteArrayReader(segment.Bytes); try { directory.Set(JpegDirectory.TagDataPrecision, reader.GetByte()); directory.Set(JpegDirectory.TagImageHeight, reader.GetUInt16()); directory.Set(JpegDirectory.TagImageWidth, reader.GetUInt16()); var componentCount = reader.GetByte(); directory.Set(JpegDirectory.TagNumberOfComponents, componentCount); // For each component, there are three bytes of data: // 1 - Component ID: 1 = Y, 2 = Cb, 3 = Cr, 4 = I, 5 = Q // 2 - Sampling factors: bit 0-3 vertical, 4-7 horizontal // 3 - Quantization table number for (var i = 0; i < componentCount; i++) { var componentId = reader.GetByte(); var samplingFactorByte = reader.GetByte(); var quantizationTableNumber = reader.GetByte(); var component = new JpegComponent(componentId, samplingFactorByte, quantizationTableNumber); directory.Set(JpegDirectory.TagComponentData1 + i, component); } } catch (IOException ex) { directory.AddError(ex.Message); } return(directory); }
/// <summary>Reads JPEG SOF values and returns them in a <see cref="JpegDirectory"/>.</summary> public JpegDirectory Extract(byte[] segmentBytes, JpegSegmentType segmentType) { var directory = new JpegDirectory(); // The value of TagCompressionType is determined by the segment type found directory.Set(JpegDirectory.TagCompressionType, (int)segmentType - (int)JpegSegmentType.Sof0); SequentialReader reader = new SequentialByteArrayReader(segmentBytes); try { directory.Set(JpegDirectory.TagDataPrecision, reader.GetByte()); directory.Set(JpegDirectory.TagImageHeight, reader.GetUInt16()); directory.Set(JpegDirectory.TagImageWidth, reader.GetUInt16()); var componentCount = reader.GetByte(); directory.Set(JpegDirectory.TagNumberOfComponents, componentCount); // for each component, there are three bytes of data: // 1 - Component ID: 1 = Y, 2 = Cb, 3 = Cr, 4 = I, 5 = Q // 2 - Sampling factors: bit 0-3 vertical, 4-7 horizontal // 3 - Quantization table number for (var i = 0; i < (int)componentCount; i++) { int componentId = reader.GetByte(); int samplingFactorByte = reader.GetByte(); int quantizationTableNumber = reader.GetByte(); var component = new JpegComponent(componentId, samplingFactorByte, quantizationTableNumber); directory.Set(JpegDirectory.TagComponentData1 + i, component); } } catch (IOException ex) { directory.AddError(ex.Message); } return directory; }