Class PDFRenderer


  • public class PDFRenderer
    extends java.lang.Object
    Renders a PDF document to an AWT BufferedImage. This class may be overridden in order to perform custom rendering.
    • Field Detail

      • LOG

        private static final org.apache.commons.logging.Log LOG
      • annotationFilter

        private AnnotationFilter annotationFilter
        Default annotations filter, returns all annotations
      • subsamplingAllowed

        private boolean subsamplingAllowed
      • renderingHints

        private java.awt.RenderingHints renderingHints
      • pageImage

        private java.awt.image.BufferedImage pageImage
      • kcmsLogged

        private static boolean kcmsLogged
      • imageDownscalingOptimizationThreshold

        private float imageDownscalingOptimizationThreshold
    • Constructor Detail

      • PDFRenderer

        public PDFRenderer​(PDDocument document)
        Creates a new PDFRenderer.
        Parameters:
        document - the document to render
    • Method Detail

      • getAnnotationsFilter

        public AnnotationFilter getAnnotationsFilter()
        Return the AnnotationFilter.
        Returns:
        the AnnotationFilter
      • setAnnotationsFilter

        public void setAnnotationsFilter​(AnnotationFilter annotationsFilter)
        Set the AnnotationFilter.

        Allows to only render annotation accepted by the filter.

        Parameters:
        annotationsFilter - the AnnotationFilter
      • isSubsamplingAllowed

        public boolean isSubsamplingAllowed()
        Value indicating if the renderer is allowed to subsample images before drawing, according to image dimensions and requested scale. Subsampling may be faster and less memory-intensive in some cases, but it may also lead to loss of quality, especially in images with high spatial frequency.
        Returns:
        true if subsampling of images is allowed, false otherwise.
      • setSubsamplingAllowed

        public void setSubsamplingAllowed​(boolean subsamplingAllowed)
        Sets a value instructing the renderer whether it is allowed to subsample images before drawing. The subsampling frequency is determined according to image size and requested scale. Subsampling may be faster and less memory-intensive in some cases, but it may also lead to loss of quality, especially in images with high spatial frequency.
        Parameters:
        subsamplingAllowed - The new value indicating if subsampling is allowed.
      • getDefaultDestination

        public RenderDestination getDefaultDestination()
        Returns:
        the defaultDestination
      • setDefaultDestination

        public void setDefaultDestination​(RenderDestination defaultDestination)
        Parameters:
        defaultDestination - the defaultDestination to set
      • getRenderingHints

        public java.awt.RenderingHints getRenderingHints()
        Get the rendering hints.
        Returns:
        the rendering hints or null if none are set.
      • setRenderingHints

        public void setRenderingHints​(java.awt.RenderingHints renderingHints)
        Set the rendering hints. Use this to influence rendering quality and speed. If you don't set them yourself or pass null, PDFBox will decide at runtime depending on the destination.
        Parameters:
        renderingHints -
      • getImageDownscalingOptimizationThreshold

        public float getImageDownscalingOptimizationThreshold()
        Returns:
        get the image downscaling optimization threshold. See getImageDownscalingOptimizationThreshold() for details.
      • setImageDownscalingOptimizationThreshold

        public void setImageDownscalingOptimizationThreshold​(float imageDownscalingOptimizationThreshold)
        Set the image downscaling optimization threshold. This must be a value between 0 and 1. When rendering downscaled images and rendering hints are set to bicubic+quality and the scaling is smaller than the threshold, a more quality-optimized but slower method will be used. The default is 0.5 which is a good compromise.
        Parameters:
        imageDownscalingOptimizationThreshold -
      • renderImage

        public java.awt.image.BufferedImage renderImage​(int pageIndex)
                                                 throws java.io.IOException
        Returns the given page as an RGB image at 72 DPI
        Parameters:
        pageIndex - the zero-based index of the page to be converted.
        Returns:
        the rendered page image
        Throws:
        java.io.IOException - if the PDF cannot be read
      • renderImage

        public java.awt.image.BufferedImage renderImage​(int pageIndex,
                                                        float scale)
                                                 throws java.io.IOException
        Returns the given page as an RGB image at the given scale. A scale of 1 will render at 72 DPI.
        Parameters:
        pageIndex - the zero-based index of the page to be converted
        scale - the scaling factor, where 1 = 72 DPI
        Returns:
        the rendered page image
        Throws:
        java.io.IOException - if the PDF cannot be read
      • renderImageWithDPI

        public java.awt.image.BufferedImage renderImageWithDPI​(int pageIndex,
                                                               float dpi)
                                                        throws java.io.IOException
        Returns the given page as an RGB image at the given DPI.
        Parameters:
        pageIndex - the zero-based index of the page to be converted
        dpi - the DPI (dots per inch) to render at
        Returns:
        the rendered page image
        Throws:
        java.io.IOException - if the PDF cannot be read
      • renderImageWithDPI

        public java.awt.image.BufferedImage renderImageWithDPI​(int pageIndex,
                                                               float dpi,
                                                               ImageType imageType)
                                                        throws java.io.IOException
        Returns the given page as an RGB image at the given DPI.
        Parameters:
        pageIndex - the zero-based index of the page to be converted
        dpi - the DPI (dots per inch) to render at
        imageType - the type of image to return
        Returns:
        the rendered page image
        Throws:
        java.io.IOException - if the PDF cannot be read
      • renderImage

        public java.awt.image.BufferedImage renderImage​(int pageIndex,
                                                        float scale,
                                                        ImageType imageType)
                                                 throws java.io.IOException
        Returns the given page as an RGB or ARGB image at the given scale.
        Parameters:
        pageIndex - the zero-based index of the page to be converted
        scale - the scaling factor, where 1 = 72 DPI
        imageType - the type of image to return
        Returns:
        the rendered page image
        Throws:
        java.io.IOException - if the PDF cannot be read
      • renderImage

        public java.awt.image.BufferedImage renderImage​(int pageIndex,
                                                        float scale,
                                                        ImageType imageType,
                                                        RenderDestination destination)
                                                 throws java.io.IOException
        Returns the given page as an RGB or ARGB image at the given scale.
        Parameters:
        pageIndex - the zero-based index of the page to be converted
        scale - the scaling factor, where 1 = 72 DPI
        imageType - the type of image to return
        destination - controlling visibility of optional content groups
        Returns:
        the rendered page image
        Throws:
        java.io.IOException - if the PDF cannot be read
      • renderPageToGraphics

        public void renderPageToGraphics​(int pageIndex,
                                         java.awt.Graphics2D graphics)
                                  throws java.io.IOException
        Renders a given page to an AWT Graphics2D instance at 72 DPI.

        Read renderPageToGraphics(int, Graphics2D, float, float, RenderDestination) before using this.

        Parameters:
        pageIndex - the zero-based index of the page to be converted
        graphics - the Graphics2D on which to draw the page
        Throws:
        java.io.IOException - if the PDF cannot be read
      • renderPageToGraphics

        public void renderPageToGraphics​(int pageIndex,
                                         java.awt.Graphics2D graphics,
                                         float scale)
                                  throws java.io.IOException
        Renders a given page to an AWT Graphics2D instance.

        Read renderPageToGraphics(int, Graphics2D, float, float, RenderDestination) before using this.

        Parameters:
        pageIndex - the zero-based index of the page to be converted
        graphics - the Graphics2D on which to draw the page
        scale - the scaling factor, where 1 = 72 DPI
        Throws:
        java.io.IOException - if the PDF cannot be read
      • renderPageToGraphics

        public void renderPageToGraphics​(int pageIndex,
                                         java.awt.Graphics2D graphics,
                                         float scaleX,
                                         float scaleY)
                                  throws java.io.IOException
        Renders a given page to an AWT Graphics2D instance.

        Read renderPageToGraphics(int, Graphics2D, float, float, RenderDestination) before using this.

        Parameters:
        pageIndex - the zero-based index of the page to be converted
        graphics - the Graphics2D on which to draw the page
        scaleX - the scale to draw the page at for the x-axis, where 1 = 72 DPI
        scaleY - the scale to draw the page at for the y-axis, where 1 = 72 DPI
        Throws:
        java.io.IOException - if the PDF cannot be read
      • renderPageToGraphics

        public void renderPageToGraphics​(int pageIndex,
                                         java.awt.Graphics2D graphics,
                                         float scaleX,
                                         float scaleY,
                                         RenderDestination destination)
                                  throws java.io.IOException
        Renders a given page to an AWT Graphics2D instance.

        Known problems:

        • rendering of PDF files with transparencies is not supported on Ubuntu, see PDFBOX-4581 and JDK-6689349. Rendering will not abort, but the pages will be rendered incorrectly.
        • Clipping the Graphics2D will not work properly, see PDFBOX-4583.
        If you encounter these problems, then you should render into an image by using the renderImage methods.
        Parameters:
        pageIndex - the zero-based index of the page to be converted
        graphics - the Graphics2D on which to draw the page
        scaleX - the scale to draw the page at for the x-axis, where 1 = 72 DPI
        scaleY - the scale to draw the page at for the y-axis, where 1 = 72 DPI
        destination - controlling visibility of optional content groups
        Throws:
        java.io.IOException - if the PDF cannot be read
      • isGroupEnabled

        public boolean isGroupEnabled​(PDOptionalContentGroup group)
        Indicates whether an optional content group is enabled.
        Parameters:
        group - the group
        Returns:
        true if the group is enabled
      • transform

        private void transform​(java.awt.Graphics2D graphics,
                               PDPage page,
                               float scaleX,
                               float scaleY)
      • isBitonal

        private boolean isBitonal​(java.awt.Graphics2D graphics)
      • createDefaultRenderingHints

        private java.awt.RenderingHints createDefaultRenderingHints​(java.awt.Graphics2D graphics)
      • createPageDrawer

        protected PageDrawer createPageDrawer​(PageDrawerParameters parameters)
                                       throws java.io.IOException
        Returns a new PageDrawer instance, using the given parameters. May be overridden.
        Throws:
        java.io.IOException
      • hasBlendMode

        private boolean hasBlendMode​(PDPage page)
      • getPageImage

        java.awt.image.BufferedImage getPageImage()
        Returns the image to which the current page is being rendered. May be null if the page is rendered to a Graphics2D object instead of a BufferedImage.
      • suggestKCMS

        private static void suggestKCMS()
      • isGoodVersion

        private static boolean isGoodVersion​(java.lang.String version,
                                             java.lang.String regex,
                                             int min)
      • isMinJdk8

        private static boolean isMinJdk8()