Abstract: A device (3400) for processing an encrypted data stream (3401), wherein the device (3400) comprises a decrypting unit (3402) for generating a decrypted data stream (3403) from the encrypted data stream (3401), a detecting unit (3404) for detecting position information of at least one intra-coded frame in the decrypted data stream (3403), and a replacement unit (3405) for replacing, based on the detected position information, portions of the encrypted data stream (3401) by corresponding portions of the decrypted data stream (3403).

Abstract: A device (3200) for processing an encrypted data stream (3201) in a cryptographic system, in which decryption data (3204) are provided for decrypting each segment (3202) of the encrypted data stream (3201) for reproduction of the decrypted data stream, wherein the device (3200) comprises a first determining unit (3209) for determining, in case of switching from a first reproduction mode (1501) of reproducing the data stream (3201) to a second reproduction mode (1502) of reproducing the data stream (3201), a current position of reproduction within the data stream, and a second determining unit (3210) for determining a starting position for starting reproduction in the second reproduction mode (1502) based on the determined current position.

Abstract: A device (3000) for processing an encrypted data stream (3001), wherein decryption messages are provided for decrypting each segment (1403) of the encrypted data stream (3001), wherein each decryption message comprises a number of decryption elements, wherein the device (3000) comprises a detection unit (3002) for detecting the number of decryption elements per decryption message, and a determining unit (3003) for determining a position for providing the decryption messages in relation to the sequence of the segments (1403), based on the detected number.

Abstract: Video information is transmitted encrypted as part of a video stream, so as to provide conditional access to the video information. The video stream comprising mutually interspersed first and second subsets of the image frames. The information for the image frames of the first subset is encrypted. A stream is broadcast (10) that contains, interspersed with one another, the information for the first subset in encrypted form and the information for the image frames of the second subset at least partly in plain form. This permits receivers (12) to detect the unencrypted parts without decryption and to generate and store pointer information (124) to the unencrypted parts. The pointer information can be used later for the purpose of trick play (126) at the receiver.