Feature/pdf blackwhite

src/EPPlus.Export.Pdf.Tests/PdfTests.cs

@@ -1336,5 +1336,33 @@ public void PdfIsDraftTest1()
             string path = _pdfPath + "DraftTest1.pdf";
             ws.SaveAsPdf(path);
         }
+
+        [TestMethod]
+        public void PdfIsBlackAndWhiteTest1()
+        {
+            using var p = OpenTemplatePackage("PDFTest.xlsx");
+            var ws = p.Workbook.Worksheets[0];
+            ws.PrinterSettings.BlackAndWhite = true;
+            string path = _pdfPath + "BlackAndWhiteTest1.pdf";
+            ws.SaveAsPdf(path);
+        }
+        [TestMethod]
+        public void PdfIsBlackAndWhiteTest2()
+        {
+            using var p = OpenTemplatePackage("CMYK.xlsx");
+            var ws = p.Workbook.Worksheets[0];
+            ws.PrinterSettings.BlackAndWhite = true;
+            string path = _pdfPath + "BlackAndWhiteTest2.pdf";
+            ws.SaveAsPdf(path);
+        }
+        [TestMethod]
+        public void PdfIsBlackAndWhiteTest3()
+        {
+            using var p = OpenTemplatePackage("ProgressiveJPEG.xlsx");
+            var ws = p.Workbook.Worksheets[0];
+            ws.PrinterSettings.BlackAndWhite = true;
+            string path = _pdfPath + "BlackAndWhiteTest3.pdf";
+            ws.SaveAsPdf(path);
+        }
     }
 }

src/EPPlus.Export.Pdf/DocumentObjects/PdfContentStream.cs

@@ -235,7 +235,7 @@ public void AddText(PdfCellContentLayout cell, Vector2 position, double textRota
                         commands.Add($"S");
                     }
                     commands.Add("BT");
-                    commands.Add(color.ToFillCommand());
+                    commands.Add((pageSettings.BlackAndWhite ? Color.Black : color).ToFillCommand());
                     commands.Add($"{textMatrix.A.ToPdfStringF4()} {textMatrix.B.ToPdfStringF4()} {textMatrix.C.ToPdfStringF4()} {textMatrix.D.ToPdfStringF4()} {textMatrix.E.ToPdfStringF4()} {textMatrix.F.ToPdfStringF4()} Tm");
                     byte currentFontId = shapedText.ShapedText.Glyphs.Length > 0 ? shapedText.ShapedText.Glyphs[0].FontId : (byte)0;
                     string currentFontLabel = shapedText.FontIdMap.ContainsKey(currentFontId)

src/EPPlus.Export.Pdf/DocumentObjects/PdfImageXObject.cs

@@ -30,7 +30,7 @@ internal class PdfImageXObject : PdfObject
         internal byte[] SoftMaskData { get; }
         internal int SoftMaskObjectNumber { get; set; }
 
-        public PdfImageXObject(int objectNumber, byte[] imageBytes, int version = 0)
+        public PdfImageXObject(int objectNumber, byte[] imageBytes, bool blackAndWhite, int version = 0)
             : base(objectNumber, version)
         {
             byte[] icoDib = null;
@@ -46,6 +46,7 @@ public PdfImageXObject(int objectNumber, byte[] imageBytes, int version = 0)
                 BitsPerComponent = 8;
                 ColorSpace = "/DeviceRGB";
                 Filter = "FlateDecode";
+                if (blackAndWhite) GrayscaleRgb(icoRgb);
                 _bytes = PdfFlate.CompressLeaveOpen(icoRgb);
                 if (icoAlpha != null)
                 {
@@ -55,20 +56,32 @@ public PdfImageXObject(int objectNumber, byte[] imageBytes, int version = 0)
             }
             else if (JpegDecoder.IsJpeg(imageBytes))
             {
-                _bytes = imageBytes;
-                Filter = "DCTDecode";
-                BitsPerComponent = 8;
-                JpegDecoder.ReadJpegInfo(imageBytes, out int width, out int height, out int components, out bool adobe);
-                Width = width;
-                Height = height;
-                if (components == 4)
+                if (blackAndWhite && JpegCmykHelper.TryDecode(imageBytes, out int gw, out int gh, out byte[] grayPixels))
                 {
-                    ColorSpace = "/DeviceCMYK";
-                    if (adobe) Decode = "[ 1 0 1 0 1 0 1 0 ]";
+                    Width = gw;
+                    Height = gh;
+                    BitsPerComponent = 8;
+                    ColorSpace = "/DeviceGray";
+                    Filter = "FlateDecode";
+                    _bytes = PdfFlate.CompressLeaveOpen(grayPixels);
                 }
                 else
                 {
-                    ColorSpace = components == 1 ? "/DeviceGray" : "/DeviceRGB";
+                    JpegDecoder.ReadJpegInfo(imageBytes, out int width, out int height, out int components, out bool adobe);
+                    _bytes = blackAndWhite ? JpegBlackWhiteHelper.MakeGrayscale(imageBytes) : imageBytes;
+                    Filter = "DCTDecode";
+                    BitsPerComponent = 8;
+                    Width = width;
+                    Height = height;
+                    if (components == 4)
+                    {
+                        ColorSpace = "/DeviceCMYK";
+                        if (adobe) Decode = "[ 1 0 1 0 1 0 1 0 ]";
+                    }
+                    else
+                    {
+                        ColorSpace = components == 1 ? "/DeviceGray" : "/DeviceRGB";
+                    }
                 }
             }
             else if (PngDecoder.IsPng(imageBytes))
@@ -81,11 +94,18 @@ public PdfImageXObject(int objectNumber, byte[] imageBytes, int version = 0)
                 {
                     BitsPerComponent = 8;
                     ColorSpace = colorType == 6 ? "/DeviceRGB" : "/DeviceGray";
-                    PngDecoder.DecodePngWithAlpha(imageBytes, width, height, colorType, out byte[] color, out byte[] alpha);
+                    PngDecoder.DecodePngWithAlpha(imageBytes, width, height, blackAndWhite, colorType, out byte[] color, out byte[] alpha);
                     _bytes = color;
                     SoftMaskData = alpha;
                     HasSoftMask = true;
                 }
+                else if (colorType == 2 && blackAndWhite)
+                {
+                    BitsPerComponent = 8;
+                    ColorSpace = "/DeviceRGB";
+                    PngDecoder.DecodePngTruecolor(imageBytes, width, height, blackAndWhite, out byte[] grayRgb);
+                    _bytes = grayRgb;
+                }
                 else
                 {
                     BitsPerComponent = bitDepth;
@@ -98,6 +118,8 @@ public PdfImageXObject(int objectNumber, byte[] imageBytes, int version = 0)
                             colors = 1;
                             break;
                         case 3:
+                            if (blackAndWhite && palette != null)
+                                GrayscaleRgb(palette);
                             int hival = palette == null || palette.Length < 3 ? 0 : (palette.Length / 3) - 1;
                             ColorSpace = "[ /Indexed /DeviceRGB " + hival + " <" + PngDecoder.ToHex(palette) + "> ]";
                             colors = 1;
@@ -124,6 +146,7 @@ public PdfImageXObject(int objectNumber, byte[] imageBytes, int version = 0)
                 BitsPerComponent = 8;
                 ColorSpace = "/DeviceRGB";
                 Filter = "FlateDecode";
+                if (blackAndWhite) GrayscaleRgb(bmpRgb);
                 _bytes = PdfFlate.CompressLeaveOpen(bmpRgb);
             }
             else if (GifDecoder.TryDecode(imageBytes, out int gifW, out int gifH, out byte[] gifRgb, out byte[] gifAlpha))
@@ -132,6 +155,7 @@ public PdfImageXObject(int objectNumber, byte[] imageBytes, int version = 0)
                 BitsPerComponent = 8;
                 ColorSpace = "/DeviceRGB";
                 Filter = "FlateDecode";
+                if (blackAndWhite) GrayscaleRgb(gifRgb);
                 _bytes = PdfFlate.CompressLeaveOpen(gifRgb);
                 if (gifAlpha != null) { SoftMaskData = PdfFlate.CompressLeaveOpen(gifAlpha); HasSoftMask = true; }
             }
@@ -142,6 +166,7 @@ public PdfImageXObject(int objectNumber, byte[] imageBytes, int version = 0)
                 BitsPerComponent = 8;
                 ColorSpace = "/DeviceRGB";
                 Filter = "FlateDecode";
+                if (blackAndWhite) GrayscaleRgb(tifRgb);
                 _bytes = PdfFlate.CompressLeaveOpen(tifRgb);
                 if (tifAlpha != null)
                 {
@@ -170,6 +195,15 @@ private PdfImageXObject(int objectNumber, int version, byte[] deflatedGray, int
             Filter = "FlateDecode";
         }
 
+        internal static void GrayscaleRgb(byte[] rgb)
+        {
+            for (int i = 0; i + 2 < rgb.Length; i += 3)
+            {
+                byte y = (byte)(0.2126 * rgb[i] + 0.7152 * rgb[i + 1] + 0.0722 * rgb[i + 2] + 0.5);
+                rgb[i] = rgb[i + 1] = rgb[i + 2] = y;
+            }
+        }
+
         internal static PdfImageXObject CreateSoftMask(int objectNumber, byte[] deflatedGray, int width, int height) => new PdfImageXObject(objectNumber, 0, deflatedGray, width, height);
 
         internal static bool CanEmbed(byte[] imageBytes)

src/EPPlus.Export.Pdf/ExcelPdf.cs

@@ -137,7 +137,7 @@ private void AddImageData()
         {
             foreach (var image in _dictionaries.Images)
             {
-                var img = image.Value.GetImageObject(_document.Count + 1);
+                var img = image.Value.GetImageObject(_document.Count + 1, _documentSettings.BlackAndWhite);
                 if (img.HasSoftMask)
                 {
                     var mask = PdfImageXObject.CreateSoftMask(_document.Count + 1, img.SoftMaskData, img.Width, img.Height);