A low-power hybrid video recording system with H.264/AVC and light-weight compression

An increasing demand for mobile video recording systems makes it important to decrease the power consumption for extending the battery lifetime. H.264/AVC video compression standard is widely used for most conventional video recording systems because it shows high compression efficiency. However, the H.264/AVC requires a large amount of computation and also large power consumption as well. Meanwhile, a light weight video compression (LWC) based on one-dimension DWT and SPIHT consumes much lower power than H.264/AVC thanks to its relatively simple coding structure although its compression efficiency is lower than that of H.264/AVC. This paper proposes a low-power hybrid video recording system that combines both H.264/AVC and LWC. LWC is used for the temporary storage and H.264/AVC is used for the permanent storage. The use of LWC for temporary storage contributes to power saving because LWC consumes much lower power than H.264/AVC does. For further power reduction, a down-sampling operation is utilized in the video recording system. The video frame scaled down by the down-sampling operation reduces the computational complexity and the power consumption for the video compression in proportion to the rate of scaling down. The estimation of power consumption shows that a power reduction of 72.5% is achieved compared to the conventional video recording system which uses only H.264/AVC.