GARbro-mirror/GameRes/ImageJPEG.cs
2014-07-21 23:26:28 +04:00

80 lines
2.8 KiB
C#

//! \file ImageJPEG.cs
//! \date Thu Jul 17 15:56:27 2014
//! \brief JPEG image implementation.
//
using System;
using System.IO;
using System.Text;
using System.ComponentModel.Composition;
using System.Windows.Media.Imaging;
using GameRes.Utility;
namespace GameRes
{
[Export(typeof(ImageFormat))]
public class JpegFormat : ImageFormat
{
public override string Tag { get { return "JPEG"; } }
public override string Description { get { return "JPEG image file format"; } }
public override uint Signature { get { return 0; } }
public int Quality { get; set; }
public JpegFormat ()
{
Extensions = new string[] { "jpg", "jpeg" };
Quality = 90;
}
public override ImageData Read (Stream file, ImageMetaData info)
{
var decoder = new JpegBitmapDecoder (file,
BitmapCreateOptions.None, BitmapCacheOption.OnLoad);
var frame = decoder.Frames[0];
frame.Freeze();
return new ImageData (frame, info);
}
public override void Write (Stream file, ImageData image)
{
var encoder = new JpegBitmapEncoder();
encoder.QualityLevel = Quality;
encoder.Frames.Add (BitmapFrame.Create (image.Bitmap));
encoder.Save (file);
}
public override ImageMetaData ReadMetaData (Stream stream)
{
if (0xff != stream.ReadByte() || 0xd8 != stream.ReadByte())
return null;
using (var file = new ArcView.Reader (stream))
{
while (-1 != file.PeekChar())
{
ushort marker = Binary.BigEndian (file.ReadUInt16());
if ((marker & 0xff00) != 0xff00)
break;
int length = Binary.BigEndian (file.ReadUInt16());
if ((marker & 0x00f0) == 0xc0 && marker != 0xffc4)
{
if (length < 8)
break;
int bits = file.ReadByte();
uint height = Binary.BigEndian (file.ReadUInt16());
uint width = Binary.BigEndian (file.ReadUInt16());
int components = file.ReadByte();
return new ImageMetaData {
Width = width,
Height = height,
BPP = bits * components,
};
}
file.BaseStream.Seek (length-2, SeekOrigin.Current);
}
return null;
}
}
}
}