JpegBitmapEncoder.cs source code in C# .NET

Source code for the .NET framework in C#

                        
Code:

                         / DotNET / DotNET / 8.0 / untmp / WIN_WINDOWS / lh_tools_devdiv_wpf / Windows / wcp / Core / System / Windows / Media / Imaging / JpegBitmapEncoder.cs / 1 / JpegBitmapEncoder.cs
                        

                        
                            //------------------------------------------------------------------------------ 
//  Microsoft Avalon
//  Copyright (c) Microsoft Corporation, All Rights Reserved
//
//  File: JpegBitmapEncoder.cs 
//
//----------------------------------------------------------------------------- 
 
using System;
using System.Security; 
using System.Security.Permissions;
using System.Collections;
using System.ComponentModel;
using System.ComponentModel.Design.Serialization; 
using System.Reflection;
using MS.Internal; 
using MS.Win32.PresentationCore; 
using System.Diagnostics;
using System.Windows.Media; 
using System.Globalization;
using System.Runtime.InteropServices;
using System.Windows.Media.Imaging;
 
using SR=MS.Internal.PresentationCore.SR;
using SRID=MS.Internal.PresentationCore.SRID; 
 
namespace System.Windows.Media.Imaging
{ 
    #region JpegBitmapEncoder

    /// 
    /// Built-in Encoder for Jpeg files. 
    /// 
    public sealed class JpegBitmapEncoder : BitmapEncoder 
    { 
        #region Constructors
 
        /// 
        /// Constructor for JpegBitmapEncoder
        /// 
        ///  
        /// Critical - will eventually create unmanaged resources
        /// PublicOK - all inputs are verified 
        ///  
        [SecurityCritical ]
        public JpegBitmapEncoder() : 
            base(true)
        {
            _supportsPreview = false;
            _supportsGlobalThumbnail = false; 
            _supportsGlobalMetadata = false;
            _supportsFrameThumbnails = true; 
            _supportsMultipleFrames = false; 
            _supportsFrameMetadata = true;
        } 

        #endregion

        #region Public Properties 

        ///  
        /// Set the quality level for the encoding. 
        /// The quality level must be between 1-100, inclusive.
        /// This property is mutually exclusive with doing lossless encoding. 
        /// 
        public int QualityLevel
        {
            get 
            {
                return _qualityLevel; 
            } 
            set
            { 
                if ((value < 1) || (value > 100))
                {
                    throw new System.ArgumentOutOfRangeException("value", SR.Get(SRID.ParameterMustBeBetween, 1, 100));
                } 

                _qualityLevel = value; 
            } 
        }
 
        /// 
        /// Set a lossless rotation value of Rotation degrees.
        /// This replaces any previous lossless transformation.
        ///  
        public Rotation Rotation
        { 
            get 
            {
                if (Rotate90) 
                {
                    return Rotation.Rotate90;
                }
                else if (Rotate180) 
                {
                    return Rotation.Rotate180; 
                } 
                else if (Rotate270)
                { 
                    return Rotation.Rotate270;
                }
                else
                { 
                    return Rotation.Rotate0;
                } 
            } 

            set 
            {
                Rotate90 = false;
                Rotate180 = false;
                Rotate270 = false; 

                switch(value) 
                { 
                    case(Rotation.Rotate0):
                        // do nothing, we reset everything above 
                        // case statement is here for clearness
                        break;

                    case(Rotation.Rotate90): 
                        Rotate90 = true;
                        break; 
 
                    case(Rotation.Rotate180):
                        Rotate180 = true; 
                        break;

                    case(Rotation.Rotate270):
                        Rotate270 = true; 
                        break;
                } 
            } 
        }
 
        /// 
        /// Set a lossless horizontal flip.
        /// This replaces any previous lossless transformation.
        ///  
        public bool FlipHorizontal
        { 
            get 
            {
                return (Convert.ToBoolean((int)_transformation & (int)WICBitmapTransformOptions.WICBitmapTransformFlipHorizontal)); 
            }
            set
            {
                if (value != this.FlipHorizontal) 
                {
                    if (value) 
                    { 
                        _transformation |= WICBitmapTransformOptions.WICBitmapTransformFlipHorizontal;
                    } 
                    else
                    {
                        _transformation &= ~WICBitmapTransformOptions.WICBitmapTransformFlipHorizontal;
                    } 
                }
            } 
        } 

        ///  
        /// Set a lossless vertical flip.
        /// This replaces any previous lossless transformation.
        /// 
        public bool FlipVertical 
        {
            get 
            { 
                return (Convert.ToBoolean((int)_transformation & (int)WICBitmapTransformOptions.WICBitmapTransformFlipVertical));
            } 
            set
            {
                if (value != this.FlipVertical)
                { 
                    if (value)
                    { 
                        _transformation |= WICBitmapTransformOptions.WICBitmapTransformFlipVertical; 
                    }
                    else 
                    {
                        _transformation &= ~WICBitmapTransformOptions.WICBitmapTransformFlipVertical;
                    }
                } 
            }
        } 
 
        #endregion
 
        #region Internal Properties / Methods

        /// 
        /// Returns the container format for this encoder 
        /// 
        ///  
        /// Critical - uses guid to create unmanaged resources 
        /// 
        internal override Guid ContainerFormat 
        {
            [SecurityCritical]
            get
            { 
                return _containerFormat;
            } 
        } 

        ///  
        /// Setups the encoder and other properties before encoding each frame
        /// 
        /// 
        /// Critical - calls Critical Initialize() 
        /// 
        [SecurityCritical] 
        internal override void SetupFrame(SafeMILHandle frameEncodeHandle, SafeMILHandle encoderOptions) 
        {
            PROPBAG2 propBag = new PROPBAG2(); 
            PROPVARIANT propValue = new PROPVARIANT();

            // There are only two encoder options supported here:
 
            if (_transformation != c_defaultTransformation)
            { 
                try 
                {
                    propBag.Init("BitmapTransform"); 
                    propValue.Init((byte) _transformation);

                    HRESULT.Check(UnsafeNativeMethods.IPropertyBag2.Write(
                        encoderOptions, 
                        1,
                        ref propBag, 
                        ref propValue)); 
                }
                finally 
                {
                    propBag.Clear();
                    propValue.Clear();
                } 
            }
 
            if (_qualityLevel != c_defaultQualityLevel) 
            {
                try 
                {
                    propBag.Init("ImageQuality");
                    propValue.Init( ((float)_qualityLevel) / 100.0f);
 
                    HRESULT.Check(UnsafeNativeMethods.IPropertyBag2.Write(
                        encoderOptions, 
                        1, 
                        ref propBag,
                        ref propValue)); 
                }
                finally
                {
                    propBag.Clear(); 
                    propValue.Clear();
                } 
            } 

            HRESULT.Check(UnsafeNativeMethods.WICBitmapFrameEncode.Initialize( 
                frameEncodeHandle,
                encoderOptions
                ));
        } 

        ///  
        /// Set a lossless rotation value of 90 degrees. 
        /// This replaces any previous lossless transformation.
        /// We can coexist with Flip operation 
        /// 
        private bool Rotate90
        {
            get 
            {
                return ((Convert.ToBoolean((int)_transformation & (int)WICBitmapTransformOptions.WICBitmapTransformRotate90) && (!Rotate270))); 
            } 
            set
            { 
                if (value != this.Rotate90)
                {
                    bool IsFlipH = FlipHorizontal;
                    bool IsFlipV = FlipVertical; 
                    if (value)
                    { 
                        _transformation = WICBitmapTransformOptions.WICBitmapTransformRotate90; 
                    }
                    else 
                    {
                        _transformation = WICBitmapTransformOptions.WICBitmapTransformRotate0;
                    }
                    FlipHorizontal = IsFlipH; 
                    FlipVertical = IsFlipV;
                } 
            } 
        }
 
        /// 
        /// Set a lossless rotation value of 180 degrees.
        /// This replaces any previous lossless transformation.
        /// We can coexist with Flip operation 
        /// 
        private bool Rotate180 
        { 
            get
            { 
                return ((Convert.ToBoolean((int)_transformation & (int)WICBitmapTransformOptions.WICBitmapTransformRotate180) && (!Rotate270)));
            }
            set
            { 
                if (value != this.Rotate180)
                { 
                    bool IsFlipH = FlipHorizontal; 
                    bool IsFlipV = FlipVertical;
                    if (value) 
                    {
                        _transformation = WICBitmapTransformOptions.WICBitmapTransformRotate180;
                    }
                    else 
                    {
                        _transformation = WICBitmapTransformOptions.WICBitmapTransformRotate0; 
                    } 
                    FlipHorizontal = IsFlipH;
                    FlipVertical = IsFlipV; 
                }
            }
        }
 
        /// 
        /// Set a lossless rotation value of 270 degrees. 
        /// This replaces any previous lossless transformation. 
        /// We can coexist with Flip operation
        ///  
        private bool Rotate270
        {
            get
            { 
                return (Convert.ToBoolean(((int)_transformation & (int)WICBitmapTransformOptions.WICBitmapTransformRotate270) == (int)WICBitmapTransformOptions.WICBitmapTransformRotate270));
            } 
            set 
            {
                if (value != this.Rotate270) 
                {
                    bool IsFlipH = FlipHorizontal;
                    bool IsFlipV = FlipVertical;
                    if (value) 
                    {
                        _transformation = WICBitmapTransformOptions.WICBitmapTransformRotate270; 
                    } 
                    else
                    { 
                        _transformation = WICBitmapTransformOptions.WICBitmapTransformRotate0;
                    }
                    FlipHorizontal = IsFlipH;
                    FlipVertical = IsFlipV; 
                }
            } 
        } 

        #endregion 

        #region Internal Abstract

        /// Need to implement this to derive from the "sealed" object 
        internal override void SealObject()
        { 
            throw new NotImplementedException(); 
        }
 
        #endregion

        #region Data Members
 
        /// 
        /// Critical - CLSID used for creation of critical resources 
        ///  
        [SecurityCritical]
        private Guid _containerFormat = MILGuidData.GUID_ContainerFormatJpeg; 

        // This happens to be the default used by the jpeg lib.
        private const int c_defaultQualityLevel = 75;
        private int _qualityLevel = c_defaultQualityLevel; 

        private const WICBitmapTransformOptions c_defaultTransformation = WICBitmapTransformOptions.WICBitmapTransformRotate0; 
        private WICBitmapTransformOptions _transformation = c_defaultTransformation; 

        #endregion 
    }

    #endregion // JpegBitmapEncoder
} 


// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.

Link Menu

Network programming in C#, Network Programming in VB.NET, Network Programming in .NET
This book is available now!
Buy at Amazon US or
Buy at Amazon UK