public Bitmap Load() { if (this.ImageWidth == 0 || this.ImageHeight == 0) { JpegThrowHelper.ThrowInvalidImageDimensions(this.ImageWidth, this.ImageHeight); } var buffer = new Buffer2D <Vector4>(MemoryGroup <Vector4> .Allocate(this.ImageWidth * this.ImageHeight, this.ImageWidth), this.ImageWidth, this.ImageHeight); using (var postProcessor = new JpegImagePostProcessor(this.RawData)) { postProcessor.PostProcess(buffer, new System.Threading.CancellationToken()); } var bitmap = new Bitmap(this.ImageWidth, this.ImageHeight); for (int y = 0; y < bitmap.Height; y++) { for (int x = 0; x < bitmap.Width; x++) { ref var p = ref buffer[x, y]; bitmap.PixelBufferView[x, y] = new Pixel() { A = p.W, B = p.Z, G = p.Y, R = p.X }; } }
/// <summary> /// Parses the input stream for file markers /// </summary> /// <param name="stream">The input stream</param> /// <param name="metadataOnly">Whether to decode metadata only.</param> /// <param name="cancellationToken">The token to monitor cancellation.</param> public void ParseStream(BufferedReadStream stream, bool metadataOnly = false, CancellationToken cancellationToken = default) { this.Metadata = new ImageMetadata(); // Check for the Start Of Image marker. stream.Read(this.markerBuffer, 0, 2); var fileMarker = new JpegFileMarker(this.markerBuffer[1], 0); if (fileMarker.Marker != JpegConstants.Markers.SOI) { JpegThrowHelper.ThrowInvalidImageContentException("Missing SOI marker."); } stream.Read(this.markerBuffer, 0, 2); byte marker = this.markerBuffer[1]; fileMarker = new JpegFileMarker(marker, (int)stream.Position - 2); this.QuantizationTables = new Block8x8F[4]; // Only assign what we need if (!metadataOnly) { const int maxTables = 4; this.dcHuffmanTables = new HuffmanTable[maxTables]; this.acHuffmanTables = new HuffmanTable[maxTables]; } // Break only when we discover a valid EOI marker. // https://github.com/SixLabors/ImageSharp/issues/695 while (fileMarker.Marker != JpegConstants.Markers.EOI || (fileMarker.Marker == JpegConstants.Markers.EOI && fileMarker.Invalid)) { cancellationToken.ThrowIfCancellationRequested(); if (!fileMarker.Invalid) { // Get the marker length int remaining = this.ReadUint16(stream) - 2; switch (fileMarker.Marker) { case JpegConstants.Markers.SOF0: case JpegConstants.Markers.SOF1: case JpegConstants.Markers.SOF2: this.ProcessStartOfFrameMarker(stream, remaining, fileMarker, metadataOnly); break; case JpegConstants.Markers.SOS: if (!metadataOnly) { this.ProcessStartOfScanMarker(stream, cancellationToken); break; } else { // It's highly unlikely that APPn related data will be found after the SOS marker // We should have gathered everything we need by now. return; } case JpegConstants.Markers.DHT: if (metadataOnly) { stream.Skip(remaining); } else { this.ProcessDefineHuffmanTablesMarker(stream, remaining); } break; case JpegConstants.Markers.DQT: this.ProcessDefineQuantizationTablesMarker(stream, remaining); break; case JpegConstants.Markers.DRI: if (metadataOnly) { stream.Skip(remaining); } else { this.ProcessDefineRestartIntervalMarker(stream, remaining); } break; case JpegConstants.Markers.APP0: this.ProcessApplicationHeaderMarker(stream, remaining); break; case JpegConstants.Markers.APP1: this.ProcessApp1Marker(stream, remaining); break; case JpegConstants.Markers.APP2: this.ProcessApp2Marker(stream, remaining); break; case JpegConstants.Markers.APP3: case JpegConstants.Markers.APP4: case JpegConstants.Markers.APP5: case JpegConstants.Markers.APP6: case JpegConstants.Markers.APP7: case JpegConstants.Markers.APP8: case JpegConstants.Markers.APP9: case JpegConstants.Markers.APP10: case JpegConstants.Markers.APP11: case JpegConstants.Markers.APP12: stream.Skip(remaining); break; case JpegConstants.Markers.APP13: this.ProcessApp13Marker(stream, remaining); break; case JpegConstants.Markers.APP14: this.ProcessApp14Marker(stream, remaining); break; case JpegConstants.Markers.APP15: case JpegConstants.Markers.COM: stream.Skip(remaining); break; } } // Read on. fileMarker = FindNextFileMarker(this.markerBuffer, stream); } }