/// <summary>
/// Progressively decodes the background image
/// </summary>
/// <param name="backgroundMap"></param>
public IWPixelMap ProgressiveDecodeBackground(IWPixelMap backgroundMap)
{
using (DjvuReader reader = Reader.CloneReader(_dataLocation, Length))
{
backgroundMap.Decode(reader);
}
return backgroundMap;
}
/// <summary>
/// Gets the background image for the page
/// </summary>
/// <returns></returns>
private System.Drawing.Bitmap GetBackgroundImage(int subsample, bool resizeImage = false)
{
BG44Chunk[] backgrounds = PageForm.GetChildrenItems <BG44Chunk>();
if (backgrounds == null || backgrounds.Count() == 0)
{
return(CreateBlankImage(Brushes.White, Info.Width, Info.Height));
}
// Get the composite background image
Wavelet.IWPixelMap backgroundMap = null;
lock (_loadingLock)
{
foreach (var background in backgrounds)
{
if (backgroundMap == null)
{
// Get the initial image
backgroundMap = background.BackgroundImage;
}
else
{
if (_isBackgroundDecoded == false)
{
background.ProgressiveDecodeBackground(backgroundMap);
}
}
}
_isBackgroundDecoded = true;
}
Bitmap result = backgroundMap.GetPixmap().ToImage();
return(resizeImage == true?ResizeImage(result, Info.Width / subsample, Info.Height / subsample) : result);
}
/// <summary>
/// Decodes the background image for this chunk
/// </summary>
/// <returns></returns>
private IWPixelMap DecodeBackgroundImage()
{
using (DjvuReader reader = Reader.CloneReader(_dataLocation, Length))
{
IWPixelMap background = new IWPixelMap();
background.Decode(reader);
return background;
}
}
/// <summary>
/// Decodes the thumbnail image for this chunk
/// </summary>
/// <returns></returns>
private IWPixelMap DecodeThumbnailImage()
{
using (DjvuReader reader = Reader.CloneReader(_dataLocation, Length))
{
IWPixelMap thumbnail = new IWPixelMap();
thumbnail.Decode(reader);
return thumbnail;
}
}
