Class OutputProfiler.SimpleImageAction

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      float resample​(OutputProfiler profiler, PDFImage image, java.util.Map<java.lang.String,​java.lang.Object> properties)
      Optionally causes an image embedded in the PDF to be resampled or recompressed.
      void setRule​(OutputProfiler.ImageType type, float threshold, float target)
      Set a resampling rule.
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Constructor Detail

      • SimpleImageAction

        public SimpleImageAction()
    • Method Detail

      • setRule

        public void setRule​(OutputProfiler.ImageType type,
                            float threshold,
                            float target)
        Set a resampling rule. Any images of the specified type that have a minimum DPI of above the "threshold" value will be resampled to "target". For example, setRule(ImageType.Color, 450, 300) will resample any images above 450dpi down to 300dpi, and leave any images under 450dpi unchanged.

        This method is called by OutputProfiler.setMaxImageDPI(org.faceless.pdf2.OutputProfiler.ImageType, float, float)

        Parameters:
        type - the image type
        threshold - the threshold resolution
        target - the target resolution
        Since:
        2.28.3
      • resample

        public float resample​(OutputProfiler profiler,
                              PDFImage image,
                              java.util.Map<java.lang.String,​java.lang.Object> properties)
        Description copied from interface: OutputProfiler.ImageAction

        Optionally causes an image embedded in the PDF to be resampled or recompressed. Returning a value other than 0 from this method will cause the image to be rebuilt; a value of less than 1 will downsample the image but that scaling factor, and the Map of properties may be modified to change the way the image is compressed.

        The supplied map will have at least the following properties:

        compressionThe compression algorithm; normally one of flate, lzw, dct, ccitfax, jbig2 or jpx
        occurranceThe number of times this image occurs in the PDF
        minResolutionThe lowest resolution the image appears at. This is normally the one used to make resampling decisions
        maxResolutionThe highest resolution the image appears at.
        compressionRatioThe compression ratio of the image
        inlineOptional, but if this property exists the image is inline

        The Map may be modified to change the way the image is compressed; specifically the "compression" property may be changed to one of "flate", "dct", "jpx", "ccittfax" ("jbig2" will hopefully be added at some point), and "compressionRatio" may be set - this will be a fairly accurate setting for "jpx", an estimate for "dct", and unused for other types of compression. A valud of "1" for "jpx" will losslessly recompress the image.

        Specified by:
        resample in interface OutputProfiler.ImageAction
        Parameters:
        profiler - the OutputProfiler this action is being run on
        image - the image being considered
        properties - a list of properties which describe how the image is stored. This map can be altered to control how the image is recompressed
        Returns:
        the scaling factor to apply to the image, or 0 for no action.