ULIC: Ultra Lightweight Image Coder on Wearable Devices

Visual display-equipped wearable devices desire efficient-yet-fast image compression methods for pervasive visual computing. However, block-based JPEG is still computationally-expensive and power-exhaustive, which is hardly affordable by most low-power and general-purpose Micro Controller Units (MCUs). This paper thus proposes the ULIC - a pixel-based, ultra-lightweight lossy image coder to fulfill the purpose. The proposed ULIC is extended substantially from the lossless QOI (Quite OK Image Format) by applying a distortion-allowable copy of pixels or blocks. Through extensive evaluations on a low-power chip, ULIC outperforms well-optimized JPEG coders with about 6%–22% compression efficiency gains, 10 \(\times \) - 30 \(\times \) faster decoding, and 17% less power consumption, making it practically attractive in applications.