Recently, mobile devices such as smart-phones and tablets have become the most important medium for delivering internet traffic, especially multimedia content, to end users. However, mobile embedded memory incurs large power consumption owing to the highly frequent access and extensive computation. This paper presents a sizing-priority based memory design methodology for low-power mobile video applications. We investigate the size dependent memory failure characteristics and effectively reduce the memory failure rate with low area overhead. Also, we develop a model for the influence of the memory failure on video output, connecting the hardware design process and application requirement. A 64-byte SRAM was fabricated and test results confirm the effectiveness of the proposed technique.