Saxonite v1.2.6.0

SacsStandardBase/Base/Utils/ImageUtils.cs

@@ -1,8 +1,14 @@
 using Sarand.Net.Standard.Base.App;
+using Sarand.Net.Standard.Base.Core;
+using Sarand.Net.Standard.Base.Helpers;
 using SixLabors.ImageSharp;
+using SixLabors.ImageSharp.Advanced;
+using SixLabors.ImageSharp.Formats;
 using SixLabors.ImageSharp.PixelFormats;
+using SixLabors.ImageSharp.Processing;
 using System;
 using System.Collections.Generic;
+using System.IO;
 using System.Text;
 
 namespace Sarand.Net.Standard.Base.Utils
@@ -19,10 +25,20 @@ namespace Sarand.Net.Standard.Base.Utils
 		public class ImageConfig
 		{
 			public byte[] ImageData { get; set; }
+			public string ImageFormatName;
+			public string DefaultMimeType;
+			public Sacs.MimeType MimeType;
 			public bool ValidImage { get; set; }
 			public int Width { get; set; }
 			public int Height { get; set; }
 		}
+
+		//-------------------------------------------------------------------
+		/// <summary>
+		/// Convert the data stream to an image and extract width and height.
+		/// </summary>
+		/// <param name="imageData"></param>
+		/// <returns>Flag to indicate whether interpretation of image data succeeded.</returns>
 		public static ImageConfig VerifyImageData(byte[] imageData)
 		{
 			String fn = className + ".VerifyImageData";
@@ -30,12 +46,17 @@ namespace Sarand.Net.Standard.Base.Utils
 			imageConfig.ImageData = imageData;
 			try
 			{
-				var image = Image.Load<Rgba32>(imageData);
-				if (image == null) return imageConfig;
-				imageConfig.Width = image.Width;
-				imageConfig.Height = image.Height;
+				IImageFormat imageFormat = null;
+				using (var image = LoadImage(imageData, out imageFormat))
+				{
+					if (image == null) return imageConfig;
+					imageConfig.ImageFormatName = imageFormat.Name;
+					imageConfig.DefaultMimeType = imageFormat.DefaultMimeType;
+					imageConfig.MimeType = EnumUtil.ParseEnum(imageConfig.ImageFormatName, Sacs.MimeType.Unknown);
+					imageConfig.Width = image.Width;
+					imageConfig.Height = image.Height;
+				}
 				imageConfig.ValidImage = true;
-				return imageConfig;
 			}
 			catch (Exception exc)
 			{
@@ -44,12 +65,73 @@ namespace Sarand.Net.Standard.Base.Utils
 			return imageConfig;
 		}
 
+		//-------------------------------------------------------------------
 		// Load from byte array.
-		public static Image LoadImage(byte[] imageData)
+		/// <summary>Convert the data stream to an image.</summary>
+		public static SixLabors.ImageSharp.Image LoadImage(byte[] imageData)
 		{
 			var image = Image.Load<Rgba32>(imageData);
 			return image;
 		}
+		/// <summary>
+		/// Convert the data stream to an image.
+		/// <para>Identify the image's format on load.</para>
+		/// </summary>
+		public static SixLabors.ImageSharp.Image LoadImage(byte[] imageData, out IImageFormat format)
+		{
+			var image = Image.Load<Rgba32>(imageData, out format);
+			return image;
+		}
+
+		//-------------------------------------------------------------------
+		// Convert to byte array.
+		/// <summary>Convert the data stream to an image.</summary>
+		public static Byte[] GetImageData(this SixLabors.ImageSharp.Image image, IImageFormat imageFormat)
+		{
+			using (MemoryStream ms = new MemoryStream())
+			{
+				var imageEncoder = image.GetConfiguration().ImageFormatsManager.FindEncoder(imageFormat);
+				image.Save(ms, imageEncoder);
+				return ms.ToArray();
+			}
+		}
+
+		//-------------------------------------------------------------------
+		/// <summary>
+		/// Resize the image with the specified limits, if required.
+		/// </summary>
+		/// <param name="config">Image data</param>
+		/// <param name="widthMax"></param>
+		/// <param name="heightMax"></param>
+		/// <returns>Flag to indicate whether operation was successful.</returns>
+		public static bool ConstrainImage(ImageConfig config, ushort widthMax, ushort heightMax)
+		{
+			String fn = className + ".ConstrainImage";
+			if (widthMax < 1 || heightMax < 1) return false;
+			if (config.Width <= widthMax && config.Height <= heightMax) return true;
+			config.ValidImage = false;
+
+			try
+			{
+				// Resize the image.
+				IImageFormat imageFormat = null;
+				using (var image = LoadImage(config.ImageData, out imageFormat))
+				{
+					double resizeProportion = Math.Min(widthMax / (double)image.Width, heightMax / (double)image.Height);
+					image.Mutate(img => img.Resize((int)(image.Width * resizeProportion), (int)(image.Height * resizeProportion)));
+					config.ImageData = image.GetImageData(imageFormat);
+					config.Width = image.Width;
+					config.Height = image.Height;
+					config.ValidImage = true;
+				}
+			}
+			catch (Exception exc)
+			{
+				SaLogger.Warn(fn + " " + ExceptionUtil.GetLogMessage(exc));
+			}
+
+			return config.ValidImage;
+		}
 
 		//-------------------------------------------------------------------
 	}