With the increasing number of users outsourcing images to cloud servers, privacy-preserving content-based image retrieval (PP-CBIR) has become a critical research area. Generating searchable cipher images that provide both robustness against attacks and efficient retrieval remains a challenge. Towards this, several PP-CBIR techniques are proposed; however, they often either compromise on search accuracy, lack sufficient security resilience, or suffer from high computational complexity. To address these challenges, we propose a PP-CBIR scheme that integrates sub-block processing-based perceptual encryption with the Color Edge Directivity Descriptor (CEDD). This method enables the calculation of feature histograms in the encrypted domain, striking a better balance between accuracy, security, and computational efficiency. Experimental evaluations conducted on the Coral-1K dataset demonstrate that both plain and cipher images exhibit comparable retrieval accuracy. Furthermore, we optimize the proposed scheme by analyzing the impact of varying feature block sizes and sub-block configurations, ensuring a comprehensive evaluation of its performance.