Interface DisplayCallback

  • All Known Implementing Classes:
    ImageWriterDisplayCallback, PageRasterDisplayCallback

    public interface DisplayCallback
    Interface representing a display callback. A display callback provides method to interract with the Ghostscript interpreter display. This can be usefull if you are interested in capturing PS or PDF page rasters. Important: in order to use a display callback, Ghostscript must be initialized with -sDEVICE=display -sDisplayHandle and -dDisplayFormat arguments. Usually set -sDisplayHandle to 0 and use -dDisplayFormat to define how display data will be sent to the displayPage method. -dDisplayFormat=16#804 sets a standard RGB ouput. Please refer to http://ghostscript.com/doc/8.54/Devices.htm to see how to set display parameters.
    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method Description
      void displayClose()
      Method called when device has been closed.
      void displayOpen()
      Method called when new device has been opened.
      void displayPage​(int width, int height, int raster, int format, int copies, int flush, byte[] imageData)
      Method called on show page.
      void displayPreClose()
      Method called when device is about to be closed.
      void displayPreSize​(int width, int height, int raster, int format)
      Method called when device is about to be resized.
      void displaySize​(int width, int height, int raster, int format)
      Method called when device has been resized.
      void displaySync()
      Method called on page flush.
      void displayUpdate​(int x, int y, int width, int height)
      Method called to notify whenever a portion of the raster is updated.
    • Method Detail

      • displayPreClose

        void displayPreClose()
                      throws GhostscriptException
        Method called when device is about to be closed. Device will not be closed until this function returns.
        Throws:
        GhostscriptException
      • displayPreSize

        void displayPreSize​(int width,
                            int height,
                            int raster,
                            int format)
                     throws GhostscriptException
        Method called when device is about to be resized.
        Parameters:
        width - Width
        height - Height
        raster - Raster
        format - Format
        Throws:
        GhostscriptException
      • displaySize

        void displaySize​(int width,
                         int height,
                         int raster,
                         int format)
                  throws GhostscriptException
        Method called when device has been resized.
        Parameters:
        width - Width
        height - Height
        raster - Raster
        format - Format
        Throws:
        GhostscriptException
      • displayPage

        void displayPage​(int width,
                         int height,
                         int raster,
                         int format,
                         int copies,
                         int flush,
                         byte[] imageData)
                  throws GhostscriptException
        Method called on show page.
        Parameters:
        width - Width
        height - Height
        raster - Raster
        format - Format
        copies - Copies
        flush - Flush
        imageData - Byte array representing image data. Data layout and order is controlled by the -dDisplayFormat argument.
        Throws:
        GhostscriptException
      • displayUpdate

        void displayUpdate​(int x,
                           int y,
                           int width,
                           int height)
                    throws GhostscriptException
        Method called to notify whenever a portion of the raster is updated.
        Parameters:
        x - X coordinate
        y - Y coordinate
        width - Width
        height - Height
        Throws:
        GhostscriptException