Local Bit-plane Decoded Pattern: A Novel Feature Descriptor for Biomedical Image Retrieval A novel image feature descriptor based on local bit-plane decoded pattern (LBDP) is introduced for indexing and retrieval of biomedical images in this paper. A local bit-plane transformation scheme is proposed to compute the local bit-plane transformed values for each image pixel from the bit-plane binary contents of its each neighboring pixels. The introduced LBDP is generated by finding a binary pattern using the difference of centre pixel’s intensity value with the local bit-plane transformed values. The efficacy of LBDP is tested under biomedical image retrieval using average retrieval precision and average retrieval rate. Three benchmark databases Emphysema-CT, NEMA-CT and OASIS-MRI are used for the evaluation and comparison of the proposed approach with recent state-of-art methods. The experimental results confirm the discriminative ability and the efficiency of the proposed LBDP forbiomedical image indexing and retrieval and prove the outperformance of existing biomedical image retrieval approaches.