Developed multi-key decryption support for MOV and DASH formats in the FFmpeg/FFmpeg repository, focusing on enhancing encrypted media handling. The work introduced new options for decryption_keys and cenc_decryption_keys, allowing users to configure multiple keys as dictionaries that map key identifiers to hexadecimal keys. This approach leveraged C programming and AV_OPT_TYPE_DICT to align with the CENC DRM workflow, primarily modifying the avformat/mov component. By enabling flexible key management, the changes broadened support for encrypted content, reduced manual intervention, and improved security. The project demonstrated depth in media encryption and video processing, addressing practical challenges in digital rights management workflows.