1366384 - How to enable image anti-aliasing in JRC DHTML Viewer?

SAP Knowledge Base Article - Public

1366384 - How to enable image anti-aliasing in JRC DHTML Viewer?

Symptom

  • Image in the chart is blurred in JRC DHTML Viewer
  • Quality of rendered image is very low
  • Image aliasing occurs in DHTML Viewer
  • (-) minus sign is missing in front of some negative numbers on Y-axis when the zoom level of the viewer is set to certain value (for instance: 100%, 150%); However, minus sign shows as expected when the zoom level of the viewer is set to 200%.

Reproducing the Issue

  1. Create a crystal report containing the chart object
  2. JRC SDK application is used to view this report
  3. The image in the chart is blurred or distorted in the DHTML Viewer
  • Crystal Reports for Eclipse version 1
  • Crystal Reports for Eclipse version 2
  • Crystal Reports XI R2
  • Cause

    By default, JRC engine sends the high DPI images to the browser as it is then askes the browser to scale down to 100% zoom. Image aliasing occurs when the browser (especially IE) scales down the image.     

    Resolution

    In web.xml file, there is a configuration option to enable image anti-aliasing. Once enabled images that are used for charts should be properly scaled by the DHTML Viewer (scaling is done at the server side then sends the scaled down image to the browser); Otherwise, the viewer will rely on the browser for image scaling.
     
    To enable this please add the following to the web.xml configuration file
          <context-param>
                <param-name>crystal_image_anti_alias</param-name>
                <param-value>on</param-value>
          </context-param>

    Keywords

    image, chart, distort, blurred, low-quality, missing, minus, Y-axis , KBA , BI-DEV-JAV , BI Software Development Kits (SDKs) - Java , Problem

    Product

    Crystal Reports, version for Eclipse 2.0