| 摘要 |
<p>A decoder (25) excludes an encryption code or key from decrypted or non-encrypted program output data. Decrypted program representative data is generated (33, 50) from an input datastream containing encrypted program data and an associated encryption code. The encrypted program data is decrypted (130, 33, 50) using the encryption code to provide decrypted program data. An output datastream is formed containing the decrypted program data but excluding the encryption code. The encryption code may be excluded by substituting (110, 55, 60, 115) non-encryption code data for the encryption code. The output datastream may also contain ancillary data formed (115) to support decoding of the decrypted program data.</p> |
