With such integration, the only other components on the board are a camera sensor, DDR2-SDRAMs, Flash memory, and an Ethernet PHY chip. Figure 2 shows the different components in such a system.

Figure 2. Different Components of an HD Surveillance Camera

Design Details: H.264 Encoder Module
The H.264 Encoder used in this design is an IP core available from EyeLytics that has optimized this core for surveillance applications. This core contains many surveillance features including multi-channel support, constant quality rate control, intra/inters modes, QPEL, CABAC, and a low gate count.

Figure 3. The H.264 Encoder Architecture

The 'Raster to Block' module (shown at the left of Figure 3) reads images from the frame buffer in raster scan order and rearranges it in macroblock format. The macroblock is then sent to the Motion Estimation Engine and the Spatial Estimation Engine. The Motion Estimation Engine reads a reference image from the frame buffer and finds the motion vector of the current macroblock by searching the reference image. The Motion Estimation Engine also determines the best partition used for each macroblock. 

The H.264 specification allows four different inter-prediction macroblock partitions and four different sub-macroblock partitions. The best motion vector and the best partition together with the corresponding estimated macroblock coding cost are sent to the Mode Decision Module. 
The best motion vector and the best partition information are also sent to the Motion Compensation Engine. The Motion Compensation Engine fetches the corresponding reference region, performs half pel and quarter pel filtering and generates the inter prediction for the current macroblock.

<< PREVIOUS NEXT>>

• R&M unveils new cabling module, Cat. 6A

• USB 3.0: Simplifying validation and debug

• Imation ships world's first wireless USB HD

• NaviSite inks deal with InMobi

• India, China add big buzz to wireless broadband