HDR

(1) (High Data Rate) A wireless data technology from QUALCOMM that provides up to a 2.4 Mbps data rate in a standard 1.25MHz CDMA voice channel. HDR can be used to enhance data capabilities in existing cdmaOne networks or in stand-alone data networks. With existing CDMA networks, some number of channels are changed from voice to data. Using a combination of TDM and CDMA, HDR shares each channel among several users, but on an as-needed basis rather than a fixed time slot as in TDMA. Optimized for IP packets and Internet access, the HDR data rate will vary depending on the distance from the mobile phone to the base station.

HDR is being used as the 3G technology for cdmaOne network carriers, known as CDMA2000. A data-only version (1XEv-Data Only) and an integrated voice-data version (1XEv-Data Voice) are available (see CDMA2000). See cellular generations.

(2) (High Dynamic Range) A photographic technique in which several shots are taken of the same high-contrast scene at different exposures. Highlights from the underexposed images and shadows from the overexposed frames are blended together to create a more natural look.

HDR and More

This image was produced in HDRSoft's Photomatix Pro, which blended the three exposures (top) into an HDR composite (below). It then applied "tone mapping," which further enhances the details in the highlights and shadows. (Image courtesy of Jacques Joffre, HDRSoft, www.hdrsoft.com)