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

    Modifier and Type
    Method
    Description
    void
    Method called when device has been closed.
    void
    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
    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
    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 Details

    • displayOpen

      void displayOpen() throws GhostscriptException
      Method called when new device has been opened. This is the first event from this device.
      Throws:
      GhostscriptException
    • 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
    • displayClose

      void displayClose() throws GhostscriptException
      Method called when device has been closed. This is the last event from this device.
      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
    • displaySync

      void displaySync() throws GhostscriptException
      Method called on page flush.
      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