Read and write Exif Profile

src/ImageSharp/Formats/Tiff/TiffDecoderMetadataCreator.cs

@@ -4,7 +4,6 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
-using SixLabors.ImageSharp.Formats.Tiff;
 using SixLabors.ImageSharp.Metadata;
 using SixLabors.ImageSharp.Metadata.Profiles.Exif;
 using SixLabors.ImageSharp.Metadata.Profiles.Icc;
@@ -57,9 +56,14 @@ namespace SixLabors.ImageSharp.Formats.Tiff
                         }
                     }
 
+                    if (coreMetadata.ExifProfile == null)
+                    {
+                        coreMetadata.ExifProfile = frame?.ExifProfile.DeepClone();
+                    }
+
                     if (coreMetadata.IptcProfile == null)
                     {
-                        if (TryGetIptc(frame.ExifProfile.Values, out var iptcBytes))
+                        if (TryGetIptc(frame.ExifProfile.Values, out byte[] iptcBytes))
                         {
                             coreMetadata.IptcProfile = new IptcProfile(iptcBytes);
                         }
@@ -95,7 +99,7 @@ namespace SixLabors.ImageSharp.Formats.Tiff
                 // Some Encoders write the data type of IPTC as long.
                 if (iptc.DataType == ExifDataType.Long)
                 {
-                    var iptcValues = (uint[])iptc.GetValue();
+                    uint[] iptcValues = (uint[])iptc.GetValue();
                     iptcBytes = new byte[iptcValues.Length * 4];
                     Buffer.BlockCopy(iptcValues, 0, iptcBytes, 0, iptcValues.Length * 4);
                     if (iptcBytes[0] == 0x1c)

src/ImageSharp/Formats/Tiff/TiffEncoderEntriesCollector.cs

@@ -66,12 +66,15 @@ namespace SixLabors.ImageSharp.Formats.Tiff
 
                 this.collector.Add(width);
                 this.collector.Add(height);
-                this.collector.Add(software);
 
                 this.ProcessResolution(image.Metadata, frameMetadata);
-
                 this.ProcessProfiles(image.Metadata, frameMetadata);
                 this.ProcessMetadata(frameMetadata);
+
+                if (!this.collector.Entries.Exists(t => t.Tag == ExifTag.Software))
+                {
+                    this.collector.Add(software);
+                }
             }
 
             private static bool IsPureMetadata(ExifTag tag)
@@ -174,9 +177,20 @@ namespace SixLabors.ImageSharp.Formats.Tiff
 
             private void ProcessProfiles(ImageMetadata imageMetadata, TiffFrameMetadata tiffFrameMetadata)
             {
-                if (imageMetadata.ExifProfile != null)
+                if (imageMetadata.ExifProfile != null && imageMetadata.ExifProfile.Parts != ExifParts.None)
                 {
-                    // todo: implement processing exif profile
+                    imageMetadata.SyncProfiles();
+                    foreach (IExifValue entry in imageMetadata.ExifProfile.Values)
+                    {
+                        if (!this.collector.Entries.Exists(t => t.Tag == entry.Tag) && entry.GetValue() != null)
+                        {
+                            ExifParts entryPart = ExifTags.GetPart(entry.Tag);
+                            if (entryPart != ExifParts.None && imageMetadata.ExifProfile.Parts.HasFlag(entryPart))
+                            {
+                                this.collector.AddOrReplace(entry.DeepClone());
+                            }
+                        }
+                    }
                 }
                 else
                 {

src/ImageSharp/Metadata/Profiles/Exif/ExifParts.cs

@@ -24,12 +24,12 @@ namespace SixLabors.ImageSharp.Metadata.Profiles.Exif
         /// <summary>
         /// ExifTags
         /// </summary>
-        ExifTags = 4,
+        ExifTags = 2,
 
         /// <summary>
         /// GPSTags
         /// </summary>
-        GpsTags = 8,
+        GpsTags = 4,
 
         /// <summary>
         /// All

tests/ImageSharp.Tests/Formats/Tiff/TiffDecoderTests.cs

@@ -42,9 +42,9 @@ namespace SixLabors.ImageSharp.Tests.Formats.Tiff
         where TPixel : unmanaged, IPixel<TPixel> => Assert.Throws<NotSupportedException>(() => provider.GetImage(TiffDecoder));
 
         [Theory]
-        [InlineData(TestImages.Tiff.RgbUncompressed, 24, 256, 256, 300, 300, PixelResolutionUnit.PixelsPerInch)]
-        [InlineData(TestImages.Tiff.SmallRgbDeflate, 24, 32, 32, 96, 96, PixelResolutionUnit.PixelsPerInch)]
-        [InlineData(TestImages.Tiff.Calliphora_GrayscaleUncompressed, 8, 804, 1198, 96, 96, PixelResolutionUnit.PixelsPerInch)]
+        [InlineData(RgbUncompressed, 24, 256, 256, 300, 300, PixelResolutionUnit.PixelsPerInch)]
+        [InlineData(SmallRgbDeflate, 24, 32, 32, 96, 96, PixelResolutionUnit.PixelsPerInch)]
+        [InlineData(Calliphora_GrayscaleUncompressed, 8, 804, 1198, 96, 96, PixelResolutionUnit.PixelsPerInch)]
         public void Identify(string imagePath, int expectedPixelSize, int expectedWidth, int expectedHeight, double expectedHResolution, double expectedVResolution, PixelResolutionUnit expectedResolutionUnit)
         {
             var testFile = TestFile.Create(imagePath);

tests/ImageSharp.Tests/Formats/Tiff/TiffMetadataTests.cs

@@ -292,8 +292,6 @@ namespace SixLabors.ImageSharp.Tests.Formats.Tiff
             Assert.Equal(frameMeta.HorizontalResolution, frameMetaOut.HorizontalResolution);
             Assert.Equal(frameMeta.VerticalResolution, frameMetaOut.VerticalResolution);
 
-            Assert.Equal("ImageSharp", frameMetaOut.ExifProfile.GetValue(ExifTag.Software).Value);
-
             if (preserveMetadata)
             {
                 Assert.Equal(tiffMeta.XmpProfile, tiffMetaOut.XmpProfile);
@@ -311,6 +309,7 @@ namespace SixLabors.ImageSharp.Tests.Formats.Tiff
             {
                 Assert.Null(tiffMetaOut.XmpProfile);
 
+                Assert.Equal("ImageSharp", frameMetaOut.ExifProfile.GetValue(ExifTag.Software).Value);
                 Assert.Null(frameMeta.ExifProfile.GetValue(ExifTag.Software)?.Value);
                 Assert.Null(frameMeta.ExifProfile.GetValue(ExifTag.ImageDescription)?.Value);
                 Assert.Null(frameMeta.ExifProfile.GetValue(ExifTag.Make)?.Value);

tests/ImageSharp.Tests/Metadata/Profiles/Exif/ExifProfileTests.cs

@@ -6,7 +6,7 @@ using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Text;
-
+using SixLabors.ImageSharp.Formats.Tiff;
 using SixLabors.ImageSharp.Metadata;
 using SixLabors.ImageSharp.Metadata.Profiles.Exif;
 using SixLabors.ImageSharp.PixelFormats;
@@ -28,7 +28,12 @@ namespace SixLabors.ImageSharp.Tests
             /// <summary>
             /// Writes a png file.
             /// </summary>
-            Png
+            Png,
+
+            /// <summary>
+            /// Writes a tiff file.
+            /// </summary>
+            Tiff,
         }
 
         private static readonly Dictionary<ExifTag, object> TestProfileValues = new Dictionary<ExifTag, object>
@@ -69,7 +74,7 @@ namespace SixLabors.ImageSharp.Tests
         [Fact]
         public void ConstructorEmpty()
         {
-            new ExifProfile((byte[])null);
+            new ExifProfile(null);
             new ExifProfile(new byte[] { });
         }
 
@@ -92,6 +97,7 @@ namespace SixLabors.ImageSharp.Tests
         [Theory]
         [InlineData(TestImageWriteFormat.Jpeg)]
         [InlineData(TestImageWriteFormat.Png)]
+        [InlineData(TestImageWriteFormat.Tiff)]
         public void WriteFraction(TestImageWriteFormat imageFormat)
         {
             using (var memStream = new MemoryStream())
@@ -135,6 +141,7 @@ namespace SixLabors.ImageSharp.Tests
         [Theory]
         [InlineData(TestImageWriteFormat.Jpeg)]
         [InlineData(TestImageWriteFormat.Png)]
+        [InlineData(TestImageWriteFormat.Tiff)]
         public void ReadWriteInfinity(TestImageWriteFormat imageFormat)
         {
             Image<Rgba32> image = TestFile.Create(TestImages.Jpeg.Baseline.Floorplan).CreateRgba32Image();
@@ -161,9 +168,17 @@ namespace SixLabors.ImageSharp.Tests
         }
 
         [Theory]
-        [InlineData(TestImageWriteFormat.Jpeg)]
-        [InlineData(TestImageWriteFormat.Png)]
-        public void SetValue(TestImageWriteFormat imageFormat)
+        /* The original exif profile has 19 values, the written profile should be 3 less.
+         1 x due to setting of null "ReferenceBlackWhite" value.
+         2 x due to use of non-standard padding tag 0xEA1C listed in EXIF Tool. We can read those values but adhere
+         strictly to the 2.3.1 specification when writing. (TODO: Support 2.3.2)
+         https://exiftool.org/TagNames/EXIF.html */
+        [InlineData(TestImageWriteFormat.Jpeg, 16)]
+        [InlineData(TestImageWriteFormat.Png, 16)]
+        /* Note: The tiff format has 24 expected profile values, because some tiff specific exif
+         values will be written in addition to the original profile. */
+        [InlineData(TestImageWriteFormat.Tiff, 24)]
+        public void SetValue(TestImageWriteFormat imageFormat, int expectedProfileValueCount)
         {
             Image<Rgba32> image = TestFile.Create(TestImages.Jpeg.Baseline.Floorplan).CreateRgba32Image();
             image.Metadata.ExifProfile.SetValue(ExifTag.Software, "ImageSharp");
@@ -206,18 +221,12 @@ namespace SixLabors.ImageSharp.Tests
             // todo: duplicate tags
             Assert.Equal(2, image.Metadata.ExifProfile.Values.Count(v => (ushort)v.Tag == 59932));
 
-            int profileCount = image.Metadata.ExifProfile.Values.Count;
             image = WriteAndRead(image, imageFormat);
 
             Assert.NotNull(image.Metadata.ExifProfile);
             Assert.Equal(0, image.Metadata.ExifProfile.Values.Count(v => (ushort)v.Tag == 59932));
 
-            // Should be 3 less.
-            // 1 x due to setting of null "ReferenceBlackWhite" value.
-            // 2 x due to use of non-standard padding tag 0xEA1C listed in EXIF Tool. We can read those values but adhere
-            // strictly to the 2.3.1 specification when writing. (TODO: Support 2.3.2)
-            // https://exiftool.org/TagNames/EXIF.html
-            Assert.Equal(profileCount - 3, image.Metadata.ExifProfile.Values.Count);
+            Assert.Equal(expectedProfileValueCount, image.Metadata.ExifProfile.Values.Count);
 
             software = image.Metadata.ExifProfile.GetValue(ExifTag.Software);
             Assert.Equal("15", software.Value);
@@ -233,20 +242,42 @@ namespace SixLabors.ImageSharp.Tests
 
             latitude = image.Metadata.ExifProfile.GetValue(ExifTag.GPSLatitude);
             Assert.Equal(expectedLatitude, latitude.Value);
+        }
 
+        [Theory]
+        [InlineData(TestImageWriteFormat.Jpeg)]
+        [InlineData(TestImageWriteFormat.Png)]
+        public void WriteOnlyExifTags_Works(TestImageWriteFormat imageFormat)
+        {
+            // Arrange
+            Image<Rgba32> image = TestFile.Create(TestImages.Jpeg.Baseline.Floorplan).CreateRgba32Image();
             image.Metadata.ExifProfile.Parts = ExifParts.ExifTags;
 
+            // Act
             image = WriteAndRead(image, imageFormat);
 
+            // Assert
             Assert.NotNull(image.Metadata.ExifProfile);
-            Assert.Equal(8, image.Metadata.ExifProfile.Values.Count);
+            Assert.Equal(7, image.Metadata.ExifProfile.Values.Count);
+            foreach (IExifValue exifProfileValue in image.Metadata.ExifProfile.Values)
+            {
+                Assert.True(ExifTags.GetPart(exifProfileValue.Tag) == ExifParts.ExifTags);
+            }
+        }
+
+        [Fact]
+        public void RemoveEntry_Works()
+        {
+            // Arrange
+            Image<Rgba32> image = TestFile.Create(TestImages.Jpeg.Baseline.Floorplan).CreateRgba32Image();
+            int profileCount = image.Metadata.ExifProfile.Values.Count;
 
+            // Assert
             Assert.NotNull(image.Metadata.ExifProfile.GetValue(ExifTag.ColorSpace));
             Assert.True(image.Metadata.ExifProfile.RemoveValue(ExifTag.ColorSpace));
             Assert.False(image.Metadata.ExifProfile.RemoveValue(ExifTag.ColorSpace));
             Assert.Null(image.Metadata.ExifProfile.GetValue(ExifTag.ColorSpace));
-
-            Assert.Equal(7, image.Metadata.ExifProfile.Values.Count);
+            Assert.Equal(profileCount - 1, image.Metadata.ExifProfile.Values.Count);
         }
 
         [Fact]
@@ -382,6 +413,7 @@ namespace SixLabors.ImageSharp.Tests
         [Theory]
         [InlineData(TestImageWriteFormat.Jpeg)]
         [InlineData(TestImageWriteFormat.Png)]
+        [InlineData(TestImageWriteFormat.Tiff)]
         public void WritingImagePreservesExifProfile(TestImageWriteFormat imageFormat)
         {
             // Arrange
@@ -456,8 +488,10 @@ namespace SixLabors.ImageSharp.Tests
                     return WriteAndReadJpeg(image);
                 case TestImageWriteFormat.Png:
                     return WriteAndReadPng(image);
+                case TestImageWriteFormat.Tiff:
+                    return WriteAndReadTiff(image);
                 default:
-                    throw new ArgumentException("Unexpected test image format, only Jpeg and Png are allowed");
+                    throw new ArgumentException("Unexpected test image format, only Jpeg, Png and Tiff are allowed");
             }
         }
 
@@ -485,6 +519,18 @@ namespace SixLabors.ImageSharp.Tests
             }
         }
 
+        private static Image<Rgba32> WriteAndReadTiff(Image<Rgba32> image)
+        {
+            using (var memStream = new MemoryStream())
+            {
+                image.SaveAsTiff(memStream, new TiffEncoder());
+                image.Dispose();
+
+                memStream.Position = 0;
+                return Image.Load<Rgba32>(memStream, new TiffDecoder());
+            }
+        }
+
         private static void TestProfile(ExifProfile profile)
         {
             Assert.NotNull(profile);