Video's presence and importance in the information and media industries has increased dramatically. With consumers no longer satisfied by still pictures, video is becoming a mainstream entertainment component on a variety of portable devices such as mobile phones, PDA's, PMP's etc.

In 2007, 22.4 billion views were logged for User-Generated Videos (UGV), up 70 percent from 2006. Most of these videos were generated on cell phones or low-quality recording equipment, making the viewing experience less than desirable.

Users expect clear, sharp images with vivid colors. Artefacts such as distortion, noise, faded colors, blurred motion and poor lighting are all distractions that minimize the entertainment experience.

Video transmission and processing systems used with digital portable devices today have many inherent problems that cause the delivery of poor-quality video. The main reasons for this are:

• Bandwidth of wireless communication is still low with respect to what is required for real time video transmission.
• Displays on digital portable devices are relatively small. Enlarging the display size significantly increases the cost, drains batteries, and makes the unit too bulky to carry.
• Current technology constraints -- both the computational power and the battery life of embedded systems used for digital portable devices -- restrict many solutions available on the market today.
• Distortions arise during all phases of video capture, compression, transmission, decompression and display.

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Figure 1: Conventional video processing flow.

Consider the typical flow for a conventional video processing pipeline depicted in Figure 1. Distortions can be induced throughout the entire procedure. Specifically:

• Discontinuities between pixels occur in the CCD when natural scenes are captured and digitized.
• Noise is generated during video capture and transmission, both spatially and temporally. In particular, temporal noise is more discernible and annoying.
• Blocky and mosquito effects are produced due to loss in some high-frequency components in DCT (Discrete Cosine Transform) domain and motion estimations by sub-pixel interpolations during video encoding. Blocky artifacts form horizontal and vertical pseudo-boundaries are very obvious in playback, especially in case of low bit-rate encoding due to higher quantization factors.
• During video encoding, deep quantization on high-frequency components in DCT domain also make video frames/fields lose details. Edges are also blurred for the same reason.
• Because only a limited gamut of colors can be received by video capturing system, colors become dim and diverge from those in real world, which causes contrast to be decreased as well.

Next: Video enhancement chips and Ipera Technology's Pixel Magic Video Engine