/// <summary>
/// Creates a new <see cref="RasterImage"/> from the specified file.
/// </summary>
/// <param name="fileName">The path to the file containing the image.</param>
/// <param name="pageNumber">The number of the page in the file from which the image should be created, starting at 0. Only useful for multi-page formats, such as PDF.</param>
/// <param name="scale">The scale factor at which to render the image.</param>
/// <param name="alpha">A boolean value indicating whether transparency (alpha) data from the image should be preserved or not.</param>
/// <param name="interpolate">A boolean value indicating whether the image should be interpolated when it is resized or not.</param>
public RasterImageFile(string fileName, int pageNumber = 0, double scale = 1, bool alpha = true, bool interpolate = true)
{
using (MuPDFContext context = new MuPDFContext())
{
using (MuPDFDocument document = new MuPDFDocument(context, fileName))
{
RoundedRectangle roundedBounds = document.Pages[pageNumber].Bounds.Round(scale);
this.Width = roundedBounds.Width;
this.Height = roundedBounds.Height;
this.HasAlpha = alpha;
this.Interpolate = interpolate;
this.Id = Guid.NewGuid().ToString();
int imageSize = document.GetRenderedSize(pageNumber, scale, alpha ? MuPDFCore.PixelFormats.RGBA : MuPDFCore.PixelFormats.RGB);
this.ImageDataAddress = Marshal.AllocHGlobal(imageSize);
this.DataHolder = new DisposableIntPtr(this.ImageDataAddress);
GC.AddMemoryPressure(imageSize);
document.Render(pageNumber, scale, alpha ? MuPDFCore.PixelFormats.RGBA : MuPDFCore.PixelFormats.RGB, this.ImageDataAddress);
}
}
}
/// <summary>
/// Creates a new <see cref="RasterImage"/> from the specified stream.
/// </summary>
/// <param name="imageStream">The stream containing the image data.</param>
/// <param name="fileType">The type of the image contained in the stream.</param>
/// <param name="pageNumber">The number of the page in the file from which the image should be created, starting at 0. Only useful for multi-page formats, such as PDF.</param>
/// <param name="scale">The scale factor at which to render the image.</param>
/// <param name="alpha">A boolean value indicating whether transparency (alpha) data from the image should be preserved or not.</param>
/// <param name="interpolate">A boolean value indicating whether the image should be interpolated when it is resized or not.</param>
public RasterImageStream(Stream imageStream, InputFileTypes fileType, int pageNumber = 0, double scale = 1, bool alpha = true, bool interpolate = true)
{
using (MuPDFContext context = new MuPDFContext())
{
IntPtr originalImageAddress;
long originalImageLength;
IDisposable toBeDisposed = null;
GCHandle handleToFree;
if (imageStream is MemoryStream ms)
{
int origin = (int)ms.Seek(0, SeekOrigin.Begin);
originalImageLength = ms.Length;
handleToFree = GCHandle.Alloc(ms.GetBuffer(), GCHandleType.Pinned);
originalImageAddress = handleToFree.AddrOfPinnedObject();
}
else
{
MemoryStream mem = new MemoryStream((int)imageStream.Length);
imageStream.CopyTo(mem);
toBeDisposed = mem;
int origin = (int)mem.Seek(0, SeekOrigin.Begin);
originalImageLength = mem.Length;
handleToFree = GCHandle.Alloc(mem.GetBuffer(), GCHandleType.Pinned);
originalImageAddress = handleToFree.AddrOfPinnedObject();
}
using (MuPDFDocument document = new MuPDFDocument(context, originalImageAddress, originalImageLength, fileType))
{
RoundedRectangle roundedBounds = document.Pages[pageNumber].Bounds.Round(scale);
this.Width = roundedBounds.Width;
this.Height = roundedBounds.Height;
this.HasAlpha = alpha;
this.Interpolate = interpolate;
this.Id = Guid.NewGuid().ToString();
int imageSize = document.GetRenderedSize(pageNumber, scale, alpha ? MuPDFCore.PixelFormats.RGBA : MuPDFCore.PixelFormats.RGB);
this.ImageDataAddress = Marshal.AllocHGlobal(imageSize);
this.DataHolder = new DisposableIntPtr(this.ImageDataAddress);
GC.AddMemoryPressure(imageSize);
document.Render(pageNumber, scale, alpha ? MuPDFCore.PixelFormats.RGBA : MuPDFCore.PixelFormats.RGB, this.ImageDataAddress);
}
handleToFree.Free();
toBeDisposed?.Dispose();
}
}
/// <summary>
/// Generates a thumbnail of the page.
/// </summary>
/// <returns>A <see cref="WriteableBitmap"/> containing the thumbnail of the page.</returns>
private WriteableBitmap GenerateThumbnail()
{
//Render the whole page.
Rectangle bounds = Document.Pages[this.FindControl <PDFRenderer>("MuPDFRenderer").PageNumber].Bounds;
//Determine the appropriate zoom factor to render a thumbnail of the right size for the NavigatorCanvas, taking into account DPI scaling
double maxDimension = Math.Max(bounds.Width, bounds.Height);
double zoom = 200 / maxDimension * ((VisualRoot as ILayoutRoot)?.LayoutScaling ?? 1);
//Get the actual size in pixels of the image.
RoundedRectangle roundedBounds = bounds.Round(zoom);
//Initialize the image
WriteableBitmap bmp = new WriteableBitmap(new PixelSize(roundedBounds.Width, roundedBounds.Height), new Vector(96, 96), Avalonia.Platform.PixelFormat.Rgba8888, AlphaFormat.Unpremul);
//Render the page to the bitmap, without marshaling.
using (ILockedFramebuffer fb = bmp.Lock())
{
Document.Render(this.FindControl <PDFRenderer>("MuPDFRenderer").PageNumber, bounds, zoom, PixelFormats.RGBA, fb.Address);
}
return(bmp);
}