Files
Umbraco-CMS/src/Umbraco.Web/Media/ImageHelper.cs

63 lines
2.3 KiB
C#

using System;
using System.Drawing;
using System.IO;
using Umbraco.Core;
using Umbraco.Web.Media.Exif;
namespace Umbraco.Web.Media
{
public static class ImageHelper
{
/// <summary>
/// Gets the dimensions of an image.
/// </summary>
/// <param name="stream">A stream containing the image bytes.</param>
/// <returns>The dimension of the image.</returns>
/// <remarks>First try with EXIF as it is faster and does not load the entire image
/// in memory. Fallback to GDI which means loading the image in memory and thus
/// use potentially large amounts of memory.</remarks>
public static Size GetDimensions(Stream stream)
{
//Try to load with exif
try
{
var jpgInfo = ImageFile.FromStream(stream);
if (jpgInfo != null
&& jpgInfo.Format != ImageFileFormat.Unknown
&& jpgInfo.Properties.ContainsKey(ExifTag.PixelYDimension)
&& jpgInfo.Properties.ContainsKey(ExifTag.PixelXDimension))
{
var height = Convert.ToInt32(jpgInfo.Properties[ExifTag.PixelYDimension].Value);
var width = Convert.ToInt32(jpgInfo.Properties[ExifTag.PixelXDimension].Value);
if (height > 0 && width > 0)
{
return new Size(width, height);
}
}
}
catch
{
//We will just swallow, just means we can't read exif data, we don't want to log an error either
}
//we have no choice but to try to read in via GDI
try
{
using (var image = Image.FromStream(stream))
{
var fileWidth = image.Width;
var fileHeight = image.Height;
return new Size(fileWidth, fileHeight);
}
}
catch (Exception)
{
//We will just swallow, just means we can't read via GDI, we don't want to log an error either
}
return new Size(Constants.Conventions.Media.DefaultSize, Constants.Conventions.Media.DefaultSize);
}
}
}