Low-Cost Unified Pixel Converter from the MIPI DSI Packets into Arbitrary Pixel Sizes

Abstract

The advance in semiconductors and image processing technologies has significantly improved visual quality, especially on mobile consumer devices. The devices require a low-cost and high-bandwidth interface to support various pixel formats on high-resolution displays; thus, the MIPI Alliance has proposed the industry-standard MIPI DSI (Display Serial Interface). The traditional implementation of DSI Rx has classified an incoming packet into three components, a header, a payload, and a checksum, by aligning the packet with the DSI PHY input width and then converting the payload into pixels. Its two-step approach has resulted in high implementation costs for supporting various pixels. This paper proposes a low-cost unified pixel converter, classifying each component and aligning the input payload into various pixel formats in only one step, thus achieving less area and lower power consumption overhead. Two terms are newly introduced for the proposal: a base and a remainder. The base size is the same as the DSI PHY input, and a remainder is a rest after the bases are aligned. The one-pixel size equals a sum of one or more bases and the remainder. The introduction allows us to implement the converter very straightforwardly due to the exact size of the base and the D-PHY input. Additionally, our approach does not require considering the header separately from the payload since the header size equals the base size. Therefore, the header detection unit is eliminated, thus reducing the complexity further. The proposed design was functionally verified in FPGA and synthesized through the Samsung 65 nm standard cell library. The synthesis result showed that the proposed design reduced by 25.7% in the area and 38.6% in the power consumption from the traditional design.