This document describes two novel image hiding schemes: Optimal Pixel Pair Matching (OPAP) and Diamond Encoding (DE). OPAP embeds secret data by adjusting pixel values at their optimal level using least significant bit substitution to minimize embedding distortion. DE extends the Exploiting Modification Direction method by concealing secret digits in a diamond-shaped neighborhood of pixel pairs using a diamond characteristic value. Experimental results show that both OPAP and DE provide acceptable image quality while embedding a significant amount of data, with DE able to embed larger payloads than OPAP by exploiting a diamond-shaped pixel neighborhood. DE selectively embeds data according to a specific notational system but maintains imperceptible stego-image quality