Encoder, decoder and methods employing partial data encryption

A method of encoding and encrypting input data (D1) to generate corresponding encoded and encrypted data (E2), via an encoder (110), wherein the encoder (110) includes a data processing arrangement for processing the input data (D1), wherein the method includes:

• (a) operating the data processing arrangement to encode the input data (D1) using a plurality of coding methods to generate a plurality of intermediate encoded data streams, wherein the plurality of intermediate encoded data streams comprises at least two critical data streams that are critical and essential for subsequent decoding of one or more remaining data streams of the plurality of intermediate encoded data streams, wherein the at least two critical data streams represents only a part of the plurality of intermediate encoded data streams;
• (b) operating the data processing arrangement to encrypt the at least one critical data stream using one or more encryption algorithms to generate at least one intermediate encrypted data stream;
• and
• (c) operating the data processing arrangement to merge unencrypted portions of the plurality of intermediate encoded data streams together with the at least two intermediate encrypted data streams to generate the encoded and encrypted data (E2).

A decoder (120) for decrypting and decoding encoded and encrypted data (E2) to generate corresponding decrypted and decoded data (D3), wherein the decoder (120) includes a data processing arrangement for processing the encoded and encrypted data (E2), wherein:

• (i) the data processing arrangement is configured to process the encoded and encrypted data (E2) to determine one or more encrypted portions and one or more unencrypted portions thereof, wherein the one or more unencrypted portions of the encoded and encrypted data (E2) comprise encoded information of a plurality of data blocks and/or data packets;
• (ii) the data processing arrangement is configured to decrypt the at least two or more encrypted portions to determine sizes and/or relative positions and/or one or more encoding methods that are associated with the plurality of data blocks and/or data packets;
• (iii) the data processing arrangement is configured to apply an inverse of the one or more encoding methods to the encoded information of the plurality of data blocks and/or data packets to decode the encoded information of the plurality of data blocks and/or data packets to generate a plurality of decoded data blocks and/or data packets;
• and
• (iv) the data processing arrangement is configured to assemble the plurality of decoded data blocks and/or data packets based on the sizes and/or relative positions associated with the plurality of data blocks and/or data packets to generate the decrypted and decoded data (D3).

A method of decrypting and decoding encoded and encrypted data (E2) to generate corresponding decrypted and decoded data (D3), via a decoder (120), wherein the decoder (120) includes a data processing arrangement for processing the encoded and encrypted data (E2), wherein the method includes:

• (i) operating the data processing arrangement to process the encoded and encrypted data (E2) to determine one or more encrypted portions and one or more unencrypted portions thereof, wherein the one or more unencrypted portions of the encoded and encrypted data (E2) comprise encoded information of a plurality of data blocks and/or data packets;
• (ii) operating the data processing arrangement to decrypt the one or more encrypted portions to determine sizes and/or relative positions and/or one or more encoding methods that are associated with the plurality of data blocks and/or data packets;
• (iii) operating the data processing arrangement to apply an inverse of the one or more encoding methods to the encoded information of the plurality of data blocks and/or data packets to decode the encoded information of the plurality of data blocks and/or data packets to generate a plurality of decoded data blocks and/or data packets;
• and
• (iv) operating the data processing arrangement to assemble the plurality of decoded data blocks and/or data packets based on the sizes and/or relative positions associated with the plurality of data blocks and/or data packets to generate the decrypted and decoded data (D3).