DA8223: Real-time 2D to 3D video and still image conversion

Converting 2D images to 3D

DA8223 operates in real-time on the RGB image data typically provided by the host application processor. The conversion to 3D is a three-stage process:

• Each 2D image (picture still or video frame) is converted into a depth map separating picture elements into foreground and background.
• Each pixel from the original 2D image is assigned a depth tag identifying if it is located in the foreground or background. The perceived degree of separation between foreground and background is realised by shifting the foreground pixels. The greater the shift, the deeper the 3D effect will appear to the viewer.
• The shifted pixel image is processed by the image formatter. This aligns and synchronises each left and right eye pixel to the 3D display’s parallax barrier filter with the resulting image appearing in 3D without the need for 3D glasses.

The whole conversion process has a latency time of less than one frame, resulting in near-instantaneous 3D conversion. This super fast conversion enables instant switching between portrait and landscape modes allowing the viewer to rotate the display at will.

Dual parallax barrier driver

DA8223 is designed to integrate seamlessly with the latest 3D displays utilising parallax barrier technology. The parallax filter layer when applied to standard handheld displays creates small slits that prevent each eye from seeing the wrong pixels.

Application

DA8223 fits between the host application processor’s display interface and the display driver IC in a typical smartphone or tablet PC application.

The small chip package is designed to mount on either the PCB, alongside the host application processor, or as a chip-on-flex, as part of the display module. This provides product designers with complete flexibility and opens up the possibility of retro fitting DA8223 into existing 3D designs.

Three operating modes allow the display of original 2D and 3D content as well as the conversion of 2D content to 3D.

• Native 3D mode. DA8223 passes 3D content direct from the host application processor and synchronises control of the parallax barrier for 3D display. This includes support for field-based stereoscopic display technologies, with a mode to dynamically produce alternating left-eye and right-eye views from traditional 2D content.
• 2D mode: DA8223 is in full bypass mode passing 2D content from the host application processor to the display with the parallax barrier switched off.
• 2D to 3D mode: DA8223 converts incoming RGB data to 3D and outputs to the display while synchronising control of the parallax barrier.

DA8223 is configured and controlled using an internal register set accessed via a standard I2C interface or SPI. The one-time-set display and parallax barrier configuration is fully programmable in order to accommodate a wide range of display technologies, screen resolutions and sizes. Once set, the configuration can be hard coded using the one-time-programmable (OTP) memory. Depth perception diagram

DA8223 provides a comfortable 3D viewing experience allowing users to watch complete movies without feeling too tired. Because different people perceive the 3D effect in different ways, DA8223 can be controlled by the user to personalise the 3D depth effect. These setting can be adjusted on-the-fly and have an immediate effect on the screen image.