feature: document template QR Code image extensions

Disco.BI/BI/Extensions/DocumentTemplateExtensions.cs

@@ -9,7 +9,6 @@ using Disco.Services.Interop.ActiveDirectory;
 using iTextSharp.text.pdf;
 using System;
 using System.Collections.Generic;
-using System.Data.Entity;
 using System.Drawing;
 using System.IO;
 using System.Linq;

Disco.BI/BI/Interop/Pdf/PdfGenerator.cs

@@ -1,8 +1,8 @@
 using Disco.BI.Extensions;
 using Disco.Data.Repository;
-using Disco.Models.BI.Expressions;
 using Disco.Models.Repository;
 using Disco.Models.Services.Documents;
+using Disco.Models.Services.Expressions.Extensions;
 using Disco.Services;
 using Disco.Services.Documents;
 using Disco.Services.Expressions;
@@ -270,14 +270,15 @@ namespace Disco.BI.Interop.Pdf
                         // Encode to QRCode byte array
                         var pageUniqueIdWidth = (int)pdfFieldPosition.position.Width;
                         var pageUniqueIdHeight = (int)pdfFieldPosition.position.Height;
-                        var pageUniqueIdEncoded = QRCodeBinaryEncoder.Encode(pageUniqueIdBytes, pageUniqueIdWidth, pageUniqueIdHeight);
+                        var pageUniqueIdEncoded = QRCodeBinaryEncoder.Encode(pageUniqueIdBytes, out var qrWidth, out var qrHeight);
 
                         // Encode byte array to Image
-                        var pageUniqueIdImageData = CCITTG4Encoder.Compress(pageUniqueIdEncoded, pageUniqueIdWidth, pageUniqueIdHeight);
+                        var pageUniqueIdImageData = CCITTG4Encoder.Compress(pageUniqueIdEncoded, qrWidth, qrHeight);
-                        var pageUniqueIdImage = iTextSharp.text.Image.GetInstance(pageUniqueIdWidth, pageUniqueIdHeight, false, 256, 1, pageUniqueIdImageData, null);
+                        var pageUniqueIdImage = iTextSharp.text.Image.GetInstance(qrWidth, qrHeight, false, 256, 1, pageUniqueIdImageData, null);
 
                         // Add to the pdf page
                         pageUniqueIdImage.SetAbsolutePosition(pdfFieldPosition.position.Left, pdfFieldPosition.position.Bottom);
+                        pageUniqueIdImage.ScaleToFit(pdfFieldPosition.position.Width, pdfFieldPosition.position.Height);
                         pdfStamper.GetOverContent(pdfFieldPosition.page).AddImage(pageUniqueIdImage);
                     }
                     // Hide Fields
@@ -315,7 +316,22 @@ namespace Disco.BI.Interop.Pdf
                                     for (int pdfFieldOrdinal = 0; pdfFieldOrdinal < fields.Size; pdfFieldOrdinal++)
                                     {
                                         AcroFields.FieldPosition pdfFieldPosition = pdfFieldPositions[pdfFieldOrdinal];
-                                        iTextSharp.text.Image pdfImage = iTextSharp.text.Image.GetInstance(imageResult.GetImage((int)(pdfFieldPosition.position.Width * 1.6), (int)(pdfFieldPosition.position.Height * 1.6)));
+
+                                        iTextSharp.text.Image pdfImage;
+                                        var imageWidth = (int)(pdfFieldPosition.position.Width * 1.6);
+                                        var imageHeight = (int)(pdfFieldPosition.position.Height * 1.6);
+                                        if (imageResult.Format == ImageExpressionFormat.Jpeg || imageResult.Format == ImageExpressionFormat.Png)
+                                        {
+                                            pdfImage = iTextSharp.text.Image.GetInstance(imageResult.GetImage(imageWidth, imageHeight));
+                                        }
+                                        else if (imageResult.Format == ImageExpressionFormat.CcittG4)
+                                        {
+                                            var imageData = imageResult.GetImage(out imageWidth, out imageHeight);
+                                            pdfImage = iTextSharp.text.Image.GetInstance(imageWidth, imageHeight, false, 256, 1, imageData.GetBuffer(), null);
+                                        }
+                                        else
+                                            throw new NotSupportedException($"Unexpected image format {imageResult.Format}");
+
                                         pdfImage.SetAbsolutePosition(pdfFieldPosition.position.Left, pdfFieldPosition.position.Bottom);
                                         pdfImage.ScaleToFit(pdfFieldPosition.position.Width, pdfFieldPosition.position.Height);
                                         pdfStamper.GetOverContent(pdfFieldPosition.page).AddImage(pdfImage);

Disco.BI/BI/Interop/Pdf/Utilities.cs

@@ -1,5 +1,7 @@
 using iTextSharp.text;
 using iTextSharp.text.pdf;
+using iTextSharp.text.pdf.codec;
+using System;
 using System.Collections.Generic;
 using System.IO;
 
@@ -7,6 +9,11 @@ namespace Disco.BI.Interop.Pdf
 {
     public static class Utilities
     {
+        public static Func<byte[], int, int, byte[]> GetCCITTG4EncoderCompressDelegate()
+        {
+            return CCITTG4Encoder.Compress;
+        }
+
         public static Stream JoinPdfs(bool InsertBlankPages, List<Stream> Pdfs)
         {
             if (Pdfs.Count == 0)

Disco.Models/Disco.Models.csproj

@@ -49,6 +49,7 @@
   </ItemGroup>
   <ItemGroup>
     <Compile Include="BI\Config\OrganisationAddress.cs" />
+    <Compile Include="Services\Expressions\Extensions\ImageExpressionFormat.cs" />
     <Compile Include="ClientServices\EnrolmentInformation\BaseBoard.cs" />
     <Compile Include="ClientServices\EnrolmentInformation\Battery.cs" />
     <Compile Include="ClientServices\EnrolmentInformation\Bios.cs" />
@@ -86,7 +87,7 @@
     <Compile Include="Services\Authorization\IClaimNavigatorItem.cs" />
     <Compile Include="Services\Authorization\IRoleToken.cs" />
     <Compile Include="Services\Documents\DocumentState.cs" />
-    <Compile Include="BI\Expressions\IImageExpressionResult.cs" />
+    <Compile Include="Services\Expressions\Extensions\IImageExpressionResult.cs" />
     <Compile Include="Services\Jobs\Statistics\DailyOpenedClosedItem.cs" />
     <Compile Include="ClientServices\EnrolResponse.cs" />
     <Compile Include="ClientServices\MacEnrol.cs" />

Disco.Models/Services/Expressions/Extensions/IImageExpressionResult.cs

@@ -1,13 +1,13 @@
 using System.IO;
 
-namespace Disco.Models.BI.Expressions
+namespace Disco.Models.Services.Expressions.Extensions
 {
     public interface IImageExpressionResult
     {
-        Stream GetImage(int Width, int Height);
+        MemoryStream GetImage(int width, int height);
-        Stream GetImage();
+        MemoryStream GetImage(out int width, out int height);
         byte Quality { get; set; }
-        bool LosslessFormat { get; set; }
+        ImageExpressionFormat Format { get; set; }
         bool ShowField { get; set; }
         string BackgroundColour { get; set; }
         bool BackgroundPreferTransparent { get; set; }

Disco.Models/Services/Expressions/Extensions/ImageExpressionFormat.cs

@@ -0,0 +1,9 @@
+namespace Disco.Models.Services.Expressions.Extensions
+{
+    public enum ImageExpressionFormat
+    {
+        Jpeg,
+        Png,
+        CcittG4,
+    }
+}

Disco.Services/Disco.Services.csproj

@@ -317,6 +317,7 @@
     <Compile Include="Expressions\Extensions\ImageResultImplementations\BitmapImageExpressionResult.cs" />
     <Compile Include="Expressions\Extensions\ImageResultImplementations\FileImageExpressionResult.cs" />
     <Compile Include="Expressions\Extensions\ImageResultImplementations\FileMontageImageExpressionResult.cs" />
+    <Compile Include="Expressions\Extensions\ImageResultImplementations\QrCodeImageExpressionResult.cs" />
     <Compile Include="Expressions\Extensions\UserExt.cs" />
     <Compile Include="Expressions\IExpressionPart.cs" />
     <Compile Include="Expressions\LazyDictionary.cs" />

Disco.Services/Documents/AttachmentImport/ImportPage.cs

@@ -113,18 +113,42 @@ namespace Disco.Services.Documents.AttachmentImport
         {
             var qrReader = new QRCodeMultiReader();
 
-            var qrReaderHints = new Dictionary<DecodeHintType, object>() {
-                { DecodeHintType.TRY_HARDER, true }
-            };
-
             var qrImageSource = new BitmapLuminanceSource((Bitmap)Image);
 
             var qrBinarizer = new HybridBinarizer(qrImageSource);
             var qrBinaryBitmap = new BinaryBitmap(qrBinarizer);
 
+            Result DetectDocumentUniqueIdentifier(BinaryBitmap bitmap)
+            {
+                var qrReaderHints = new Dictionary<DecodeHintType, object>() {
+                    { DecodeHintType.TRY_HARDER, true }
+                };
+
+                var qrCodeResults = qrReader.decodeMultiple(bitmap, qrReaderHints);
+
+                if (qrCodeResults != null && qrCodeResults.Length > 0)
+                {
+                    if (qrCodeResults.Length > 1)
+                    {
+                        // multiple qr codes on page, test for byte-mark
+                        foreach (var qr in qrCodeResults)
+                        {
+                            if (qr.ResultMetadata.TryGetValue(ResultMetadataType.BYTE_SEGMENTS, out var byteSegments))
+                            {
+                                var qrBytes = ((List<byte[]>)byteSegments)[0];
+                                if (DocumentUniqueIdentifier.IsDocumentUniqueIdentifier(qrBytes))
+                                    return qr;
+                            }
+                        }
+                    }
+                    return qrCodeResults[0];
+                }
+                return null;
+            }
+
             try
             {
-                qrCodeResult = qrReader.decodeMultiple(qrBinaryBitmap, qrReaderHints)?.FirstOrDefault();
+                qrCodeResult = DetectDocumentUniqueIdentifier(qrBinaryBitmap);
                 qrCodeResultScale = 1F;
             }
             catch (ReaderException)
@@ -148,7 +172,7 @@ namespace Disco.Services.Documents.AttachmentImport
 
                     try
                     {
-                        qrCodeResult = qrReader.decodeMultiple(qrBinaryBitmap, qrReaderHints)?.FirstOrDefault();
+                        qrCodeResult = DetectDocumentUniqueIdentifier(qrBinaryBitmap);
                         qrCodeResultScale = 1.75F;
                     }
                     catch (ReaderException)
@@ -171,7 +195,7 @@ namespace Disco.Services.Documents.AttachmentImport
 
                         try
                         {
-                            qrCodeResult = qrReader.decodeMultiple(qrBinaryBitmap, qrReaderHints)?.FirstOrDefault();
+                            qrCodeResult = DetectDocumentUniqueIdentifier(qrBinaryBitmap);
                             qrCodeResultScale = 2F;
                         }
                         catch (ReaderException)

Disco.Services/Documents/QRCodeBinaryEncoder.cs

@@ -8,8 +8,24 @@ namespace Disco.Services.Documents
 {
     public static class QRCodeBinaryEncoder
     {
+        public static byte[] Encode(string content, ErrorCorrectionLevel ecLevel, out int width, out int height)
+        {
+            var code = Encoder.encode(content, ecLevel, null);
 
-        public static byte[] Encode(byte[] Content, int Width, int Height)
+            var array = code.Matrix.Array;
+            width = code.Matrix.Width;
+            height = code.Matrix.Height;
+
+            return scaleMatrix(code.Matrix.Array, width, height);
+        }
+
+        public static byte[] Encode(string content, ErrorCorrectionLevel ecLevel, int width, int height)
+        {
+            var code = Encoder.encode(content, ecLevel, null);
+            return scaleMatrix(code.Matrix.Array, width, height);
+        }
+
+        public static byte[] Encode(byte[] content, out int width, out int height)
         {
             var ecLevel = ErrorCorrectionLevel.L;
             var bits = new BitArray();
@@ -17,7 +33,7 @@ namespace Disco.Services.Documents
             var mode = Mode.BYTE;
             var bitsNeeded = 4 +
                 mode.getCharacterCountBits(ZXing.QrCode.Internal.Version.getVersionForNumber(1)) +
-                (Content.Length * 8);
+                (content.Length * 8);
 
             var version = ChooseVersion(bitsNeeded, out ecLevel);
             var ecBlocks = version.getECBlocksForLevel(ecLevel);
@@ -28,12 +44,12 @@ namespace Disco.Services.Documents
             bits.appendBits(mode.Bits, 4);
 
             // Write the number of bytes
-            bits.appendBits(Content.Length, mode.getCharacterCountBits(version));
+            bits.appendBits(content.Length, mode.getCharacterCountBits(version));
 
             // Write the bytes
-            for (int i = 0; i < Content.Length; i++)
+            for (int i = 0; i < content.Length; i++)
             {
-                bits.appendBits(Content[i], 8);
+                bits.appendBits(content[i], 8);
             }
 
             // Terminate the bit stream
@@ -72,7 +88,10 @@ namespace Disco.Services.Documents
             MatrixUtil.buildMatrix(finalBits, ecLevel, version, maskPattern, matrix);
 
             // Render matrix to bytes
-            return scaleMatrix(matrix.Array, Width, Height);
+            width = matrix.Width;
+            height = matrix.Height;
+            return scaleMatrix(matrix.Array, width, height);
+            //return FlattenMatrix(matrix.Array, width, height);
         }
 
         private static ZXing.QrCode.Internal.Version ChooseVersion(int RequiredBits, out ErrorCorrectionLevel ECLevel)
@@ -242,17 +261,17 @@ namespace Disco.Services.Documents
             return bestMaskPattern;
         }
 
-        private static byte[] scaleMatrix(byte[][] matrix, int Width, int Height)
+        private static byte[] scaleMatrix(byte[][] matrix, int width, int height)
         {
             var matrixWidth = matrix[0].Length;
             var matrixHeight = matrix.Length;
-            Width = Math.Max(Width, matrixWidth);
+            width = Math.Max(width, matrixWidth);
-            Height = Math.Max(Height, matrixHeight);
+            height = Math.Max(height, matrixHeight);
-            var byteColumns = (Width + 7) / 8;
+            var byteColumns = (width + 7) / 8;
-            var outputBytes = new byte[byteColumns * Height];
+            var outputBytes = new byte[byteColumns * height];
-            var scale = Math.Min(Width / (matrixWidth + 1), Height / (matrixHeight + 1));
+            var scale = Math.Max(1, Math.Min(width / (matrixWidth + 1), height / (matrixHeight + 1)));
-            var offsetX = (Width - (matrixWidth * scale)) / 2;
+            var offsetX = (width - (matrixWidth * scale)) / 2;
-            var offsetY = (Height - (matrixHeight * scale)) / 2;
+            var offsetY = (height - (matrixHeight * scale)) / 2;
             // initialize output bytes
             for (int i = 0; i < outputBytes.Length; i++)
             {

Disco.Services/Expressions/Expression.cs

@@ -1,7 +1,7 @@
 using Disco.Data.Repository;
-using Disco.Models.BI.Expressions;
 using Disco.Models.Repository;
 using Disco.Models.Services.Documents;
+using Disco.Models.Services.Expressions.Extensions;
 using Disco.Services.Plugins.Features.DetailsProvider;
 using Spring.Core.TypeResolution;
 using Spring.Expressions;

Disco.Services/Expressions/Extensions/ImageExt.cs

@@ -118,15 +118,28 @@ namespace Disco.Services.Expressions.Extensions
         }
         public static BitmapImageExpressionResult OrganisationLogo()
         {
-            var configCache = new Disco.Data.Configuration.SystemConfiguration(null);
+            var configCache = new Data.Configuration.SystemConfiguration(null);
             BitmapImageExpressionResult result;
             using (var orgLogo = configCache.OrganisationLogo)
             {
                 result = ImageFromStream(orgLogo);
             }
-            result.LosslessFormat = true;
+            result.Format = Models.Services.Expressions.Extensions.ImageExpressionFormat.Png;
             return result;
         }
 
+        public static QrCodeImageExpressionResult QrCode(string content)
+        {
+            return new QrCodeImageExpressionResult(content, 'M');
+        }
+
+        public static QrCodeImageExpressionResult QrCode(string content, string errorCorrectionLevel)
+        {
+            if (string.IsNullOrWhiteSpace(errorCorrectionLevel))
+                errorCorrectionLevel = "M";
+
+            return new QrCodeImageExpressionResult(content, errorCorrectionLevel[0]);
+        }
+
     }
 }

Disco.Services/Expressions/Extensions/ImageResultImplementations/BaseImageExpressionResult.cs

@@ -1,4 +1,4 @@
-using Disco.Models.BI.Expressions;
+using Disco.Models.Services.Expressions.Extensions;
 using System;
 using System.Drawing;
 using System.IO;
@@ -8,33 +8,35 @@ namespace Disco.Services.Expressions.Extensions.ImageResultImplementations
     public abstract class BaseImageExpressionResult : IImageExpressionResult
     {
         public byte Quality { get; set; }
-        public bool LosslessFormat { get; set; }
+        public ImageExpressionFormat Format { get; set; }
         public bool ShowField { get; set; }
         public string BackgroundColour { get; set; }
         public bool BackgroundPreferTransparent { get; set; }
 
         public BaseImageExpressionResult()
         {
-            LosslessFormat = false;
+            Format = ImageExpressionFormat.Jpeg;
             Quality = 90;
             ShowField = false;
             BackgroundPreferTransparent = true;
         }
 
-        public abstract Stream GetImage(int Width, int Height);
+        public abstract MemoryStream GetImage(int width, int height);
-        public abstract Stream GetImage();
+        public abstract MemoryStream GetImage(out int width, out int height);
 
-        protected Stream RenderImage(Image SourceImage, int Width, int Height)
+        protected MemoryStream RenderBitmapImage(Image SourceImage, int Width, int Height)
         {
             if (SourceImage == null)
-                throw new ArgumentNullException("SourceImage");
+                throw new ArgumentNullException(nameof(SourceImage));
             if (Width <= 0)
-                throw new ArgumentOutOfRangeException("Width", "Width must be > 0");
+                throw new ArgumentOutOfRangeException(nameof(Width), "Width must be > 0");
             if (Height <= 0)
-                throw new ArgumentOutOfRangeException("Height", "Height must be > 0");
+                throw new ArgumentOutOfRangeException(nameof(Height), "Height must be > 0");
+            if (Format != ImageExpressionFormat.Jpeg && Format != ImageExpressionFormat.Png)
+                throw new NotSupportedException($"The format {Format} is not supported by this method");
 
             Brush backgroundBrush = null;
-            if (!LosslessFormat || !BackgroundPreferTransparent)
+            if (Format == ImageExpressionFormat.Jpeg || !BackgroundPreferTransparent)
             {
                 if (string.IsNullOrEmpty(BackgroundColour))
                     backgroundBrush = Brushes.White;
@@ -44,22 +46,28 @@ namespace Disco.Services.Expressions.Extensions.ImageResultImplementations
 
             using (Image resizedImage = SourceImage.ResizeImage(Width, Height, backgroundBrush))
             {
-                return OutputImage(resizedImage);
+                return OutputBitmapImage(resizedImage);
             }
         }
 
-        protected Stream OutputImage(Image SourceImage)
+        protected MemoryStream OutputBitmapImage(Image SourceImage)
         {
+            if (Format != ImageExpressionFormat.Jpeg && Format != ImageExpressionFormat.Png)
+                throw new NotSupportedException($"The format {Format} is not supported by this method");
+
             MemoryStream imageStream = new MemoryStream();
-            if (LosslessFormat)
+            if (Format == ImageExpressionFormat.Png)
             { // Lossless Format - PNG
                 SourceImage.SavePng(imageStream);
             }
-            else
+            else if (Format == ImageExpressionFormat.Jpeg)
             { // Lossy Format - JPG
                 var quality = Math.Min(100, Math.Max(1, (int)Quality));
                 SourceImage.SaveJpg(quality, imageStream);
             }
+            else
+                throw new NotSupportedException($"Unexpected format {Format}");
+
             imageStream.Position = 0;
             return imageStream;
         }

Disco.Services/Expressions/Extensions/ImageResultImplementations/BitmapImageExpressionResult.cs

@@ -16,14 +16,19 @@ namespace Disco.Services.Expressions.Extensions.ImageResultImplementations
             this.Image = Image;
         }
 
-        public override Stream GetImage(int Width, int Height)
+        public override MemoryStream GetImage(int width, int height)
         {
-            return RenderImage(Image, Width, Height);
+            return RenderBitmapImage(Image, width, height);
         }
 
-        public override Stream GetImage()
+        public override MemoryStream GetImage(out int width, out int height)
         {
-            return OutputImage(Image);
+            var image = Image;
+            
+            width = image.Width;
+            height = image.Height;
+            
+            return OutputBitmapImage(image);
         }
     }
 }

Disco.Services/Expressions/Extensions/ImageResultImplementations/FileImageExpressionResult.cs

@@ -18,20 +18,28 @@ namespace Disco.Services.Expressions.Extensions.ImageResultImplementations
             this.AbsoluteFilePath = AbsoluteFilePath;
         }
 
-        public override Stream GetImage(int Width, int Height)
+        public override MemoryStream GetImage(int width, int height)
         {
-            using (Image SourceImage = Bitmap.FromFile(AbsoluteFilePath))
+            using (var sourceImage = Image.FromFile(AbsoluteFilePath))
             {
-                return RenderImage(SourceImage, Width, Height);
+                return RenderBitmapImage(sourceImage, width, height);
             }
         }
 
-        public override Stream GetImage()
+        public override MemoryStream GetImage(out int width, out int height)
         {
             var stream = new MemoryStream();
             using (var fileStream = File.OpenRead(AbsoluteFilePath))
                 fileStream.CopyTo(stream);
             stream.Position = 0;
+
+            using (var sourceImage = Image.FromStream(stream))
+            {
+                width = sourceImage.Width;
+                height = sourceImage.Height;
+            }
+            stream.Position = 0;
+
             return stream;
         }
     }

Disco.Services/Expressions/Extensions/ImageResultImplementations/FileMontageImageExpressionResult.cs

@@ -27,17 +27,17 @@ namespace Disco.Services.Expressions.Extensions.ImageResultImplementations
             Padding = 4;
         }
 
-        public override Stream GetImage(int Width, int Height)
+        public override MemoryStream GetImage(int width, int height)
         {
-            return DoLayout(Width, Height);
+            return DoLayout(width, height, out _, out _);
         }
 
-        public override Stream GetImage()
+        public override MemoryStream GetImage(out int width, out int height)
         {
-            return DoLayout(width: null, height: null);
+            return DoLayout(width: null, height: null, out width, out height);
         }
 
-        private Stream DoLayout(int? width, int? height)
+        private MemoryStream DoLayout(int? width, int? height, out int resultWidth, out int resultHeight)
         {
             List<Image> images = new List<Image>();
             try
@@ -81,7 +81,7 @@ namespace Disco.Services.Expressions.Extensions.ImageResultImplementations
                         montageGraphics.SmoothingMode = SmoothingMode.HighQuality;
 
                         // Draw Background
-                        if (!LosslessFormat || !BackgroundPreferTransparent)
+                        if (Format == Models.Services.Expressions.Extensions.ImageExpressionFormat.Jpeg || !BackgroundPreferTransparent)
                         {
                             Brush backgroundBrush = Brushes.White;
                             if (!string.IsNullOrEmpty(BackgroundColour))
@@ -96,7 +96,9 @@ namespace Disco.Services.Expressions.Extensions.ImageResultImplementations
                         else
                             DoTableLayout(images, montageGraphics);
                     }
-                    return OutputImage(montageImage);
+                    resultWidth = width.Value;
+                    resultHeight = height.Value;
+                    return OutputBitmapImage(montageImage);
                 }
             }
             catch (Exception) { throw; }
@@ -111,7 +113,6 @@ namespace Disco.Services.Expressions.Extensions.ImageResultImplementations
 
         private void DoHorizontalLayout(List<Image> Images, Graphics MontageGraphics)
         {
-
             float imageScale;
             float imagePosition = 0;
             int imagesWidthTotal = Images.Sum(i => i.Width);

Disco.Services/Expressions/Extensions/ImageResultImplementations/QrCodeImageExpressionResult.cs

@@ -0,0 +1,122 @@
+using Disco.Models.Services.Expressions.Extensions;
+using Disco.Services.Documents;
+using System;
+using System.Drawing;
+using System.Drawing.Imaging;
+using System.IO;
+using System.Runtime.InteropServices;
+using ZXing.QrCode.Internal;
+
+namespace Disco.Services.Expressions.Extensions.ImageResultImplementations
+{
+    public class QrCodeImageExpressionResult : BaseImageExpressionResult
+    {
+        public static Func<byte[], int, int, byte[]> CCITTG4EncoderCompressDelegate;
+        public string Data { get; }
+        public char ErrorCorrectionLevel { get; }
+        private readonly ErrorCorrectionLevel ecLevel;
+
+        public QrCodeImageExpressionResult(string data, char errorCorrectionLevel)
+        {
+            Data = data;
+            ErrorCorrectionLevel = errorCorrectionLevel;
+
+            switch (errorCorrectionLevel)
+            {
+                case 'l':
+                case 'L':
+                    ecLevel = ZXing.QrCode.Internal.ErrorCorrectionLevel.L;
+                    break;
+                case 'm':
+                case 'M':
+                    ecLevel = ZXing.QrCode.Internal.ErrorCorrectionLevel.M;
+                    break;
+                case 'q':
+                case 'Q':
+                    ecLevel = ZXing.QrCode.Internal.ErrorCorrectionLevel.Q;
+                    break;
+                case 'h':
+                case 'H':
+                    ecLevel = ZXing.QrCode.Internal.ErrorCorrectionLevel.H;
+                    break;
+                default:
+                    throw new ArgumentException("Error correction level must be L, M, Q or H");
+            }
+
+            Format = ImageExpressionFormat.CcittG4;
+            Quality = 90;
+            ShowField = false;
+            BackgroundPreferTransparent = true;
+        }
+
+        public override MemoryStream GetImage(int width, int height)
+        {
+            var rawImage = QRCodeBinaryEncoder.Encode(Data, ecLevel, width, height);
+            return RenderStream(rawImage, width, height);
+        }
+
+        public override MemoryStream GetImage(out int width, out int height)
+        {
+            var rawImage = QRCodeBinaryEncoder.Encode(Data, ecLevel, out width, out height);
+            return RenderStream(rawImage, width, height);
+        }
+
+        private MemoryStream RenderStream(byte[] data, int width, int height)
+        {
+            if (Format == ImageExpressionFormat.CcittG4)
+            {
+                if (CCITTG4EncoderCompressDelegate == null)
+                    throw new InvalidOperationException($"The {CCITTG4EncoderCompressDelegate} delegate has not been initialized");
+
+                var result = CCITTG4EncoderCompressDelegate(data, width, height);
+                return new MemoryStream(result, 0, result.Length, false, true);
+            }
+            else
+            {
+                using (var bitmap = RenderBitmap(data, width, height))
+                {
+                    return OutputBitmapImage(bitmap);
+                }
+            }
+        }
+
+        private Image RenderBitmap(byte[] data, int width, int height)
+        {
+            var bitmap = new Bitmap(width, height, PixelFormat.Format1bppIndexed);
+            bitmap.Palette.Entries[0] = Color.Black;
+            bitmap.Palette.Entries[0] = Color.White;
+
+            var pixelData = bitmap.LockBits(new Rectangle(Point.Empty, bitmap.Size), ImageLockMode.WriteOnly, PixelFormat.Format1bppIndexed);
+            try
+            {
+                for (int y = 0; y < height; y++)
+                {
+                    var offset = y * width;
+                    var buffer = new byte[(width + 7) / 8];
+                    var bufferOffset = 0;
+                    var bitOffset = 0;
+                    for (int x = 0; x < width; x++)
+                    {
+                        var pixel = data[offset + x];
+                        if (pixel != 0)
+                        {
+                            buffer[bufferOffset] = (byte)(buffer[bufferOffset] | (byte)((128) >> bitOffset));
+                        }
+                        if (bitOffset == 8)
+                        {
+                            bufferOffset++;
+                            bitOffset = 0;
+                        }
+                    }
+                    Marshal.Copy(buffer, 0, pixelData.Scan0, buffer.Length);
+                }
+            }
+            finally
+            {
+                bitmap.UnlockBits(pixelData);
+            }
+
+            return bitmap;
+        }
+    }
+}

Disco.Web/App_Start/AppConfig.cs

@@ -53,6 +53,7 @@ namespace Disco.Web
             InitalizeCoreEnvironment(Database);
 
             // Initialize Expressions
+            Disco.Services.Expressions.Extensions.ImageResultImplementations.QrCodeImageExpressionResult.CCITTG4EncoderCompressDelegate = Disco.BI.Interop.Pdf.Utilities.GetCCITTG4EncoderCompressDelegate();
             Disco.Services.Expressions.Expression.InitializeExpressions();
 
             // Initialize Job Queues