ImageXObject.cs :  » PDF » PDF-Clown » it » stefanochizzolini » clown » documents » contents » xObjects » C# / CSharp Open Source

/*
  Copyright 2006,2007,2008 Stefano Chizzolini. http://clown.stefanochizzolini.it

  Contributors:
    * Stefano Chizzolini (original code developer, http://www.stefanochizzolini.it)

  This file should be part of the source code distribution of "PDF Clown library"
  (the Program): see the accompanying README files for more info.

  This Program is free software; you can redistribute it and/or modify it under
  the terms of the GNU General Public License as published by the Free Software
  Foundation; either version 2 of the License, or (at your option) any later version.

  This Program is distributed in the hope that it will be useful, but WITHOUT ANY
  WARRANTY, either expressed or implied; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the License for more details.

  You should have received a copy of the GNU General Public License along with this
  Program (see README files); if not, go to the GNU website (http://www.gnu.org/).

  Redistribution and use, with or without modification, are permitted provided that such
  redistributions retain the above copyright notice, license and disclaimer, along with
  this list of conditions.
*/

using it.stefanochizzolini.clown;
using it.stefanochizzolini.clown.documents;
using it.stefanochizzolini.clown.objects;

using System;
using System.Drawing;

namespace it.stefanochizzolini.clown.documents.contents.xObjects{
  /**
    <summary>Image external object [PDF:1.6:4.8.4].</summary>
  */
  public class ImageXObject
    : XObject
  {
    #region dynamic
    #region constructors
    public ImageXObject(
      Document context,
      PdfStream baseDataObject
      ) : base(
        context,
        baseDataObject
        )
    {
      /*
        NOTE: It's caller responsability to adequately populate the stream
        header and body in order to instantiate a valid object; header entries like
        'Width', 'Height', 'ColorSpace', 'BitsPerComponent' MUST be defined
        appropriately.
      */
      baseDataObject.Header[PdfName.Subtype] = PdfName.Image;
    }

    internal ImageXObject(
      PdfDirectObject baseObject
      ) : base(baseObject)
    {}
    #endregion

    #region interface
    #region public
    /**
      <summary>Gets the number of bits per color component.</summary>
    */
    public int BitsPerComponent
    {get{return ((PdfInteger)BaseDataObject.Header[PdfName.BitsPerComponent]).RawValue;}}

    public override object Clone(
      Document context
      )
    {throw new NotImplementedException();}

    /**
      <summary>Gets the color space in which samples are specified.</summary>
    */
    public string ColorSpace
    {get{return ((PdfName)BaseDataObject.Header[PdfName.ColorSpace]).RawValue;}}

    public override double[] GetMatrix(
      )
    {
      Size size = Size;

      /*
        NOTE: Image-space-to-user-space matrix is [1/w 0 0 1/h 0 0],
        where w and h are the width and height of the image in samples [PDF:1.6:4.8.3].
      */
      return new double[]
        {
          1d / size.Width, // a.
          0, // b.
          0, // c.
          1d / size.Height, // d.
          0, // e.
          0 // f.
        };
    }

    /**
      <summary>Gets the size of the image (in samples).</summary>
    */
    public override Size Size
    {
      get
      {
        PdfDictionary header = BaseDataObject.Header;

        return new Size(
          ((PdfInteger)header[PdfName.Width]).RawValue,
          ((PdfInteger)header[PdfName.Height]).RawValue
          );
      }
      set{throw new NotSupportedException();}
    }
    #endregion
    #endregion
    #endregion
  }
}