Transport stream encryption device and its editing device and method for use therein

1. A transport stream encryption device, comprising:

a general-purpose bus connecting the transport stream encryption device to a storage device;

a detection unit for detecting headers including at least a TS header, and a PES header of a PES packet existing in a payload of a TS packet, a GOP header existing in a payload of a video PES packet from an input transport stream which is not encrypted;

an encryption unit for encrypting a remaining part of the input transport stream except at least the headers which are detected and storing an encrypted transport stream, which includes the headers not being encrypted and the remaining part being encrypted, into the storage device through the general-purpose bus;

a moving picture restoration unit for receiving the encrypted transport stream from the storage device through the general-purpose bus and for restoring a moving picture from the encrypted transport stream;

a representative image generation unit for generating representative images corresponding to all or a part of GOPs respectively from the restored moving picture and storing the representative images to the storage device together with time codes which are related to the representative images; and

a transport stream editing device, comprising:

a detection unit for detecting the headers from the encrypted transport stream stored in the storage device; and

an editing unit for editing the encrypted transport stream without decryption in such a way as to include a GOP selected by a user with reference to representative images in units of TS packets ranging from a TS packet where the GOP header is detected to a TS packet previous to a TS packet where a subsequent GOP header is detected out of TS packets having an identical PID.

2. The editing device according to claim 1

wherein said detection unit further detects a sequence header and a sequence end code existing in the payload of the video PES packet.

3. A transport stream encryption method, comprising the steps of:

detecting headers at least a TS header, and a PES header of a PES packet existing in a payload of a TS packet, a GOP header existing in a payload of a video PES packet from an input transport stream which is not encrypted;

encrypting a remaining part of the input transport stream except at least the headers which are detected and storing an encrypted transport stream, which includes the headers not being encrypted and the remaining part being encrypted, into a storage device through a general-purpose bus;

receiving the encrypted transport stream from the storage device through the general-purpose bus;

restoring a moving picture from the encrypted transport stream;

generating representative images corresponding to all or a part of GOPs respectively from the restored moving picture and storing the representative images to the storage device together with time codes which are related to the representative images; and

a transport stream editing device, comprising:

a detection unit for detecting the headers from the encrypted transport stream stored in the storage device; and

an editing unit for editing the encrypted transport stream without decryption in such a way as to include a GOP selected by a user with reference to representative images in units of TS packets ranging from a TS packet where the GOP header is detected to a TS packet previous to a TS packet where a subsequent GOP header is detected out of TS packets having an identical PID.

4. A transport stream editing method, comprising the steps of:

detecting headers from an encrypted transport stream stored in a storage device; and

editing the encrypted transport stream without decryption in such a way as to include a GOP selected by a user with reference to representative images generated from a restored moving picture in units of TS packets ranging from a TS packet where a GOP header is detected to a TS packet previous to a TS packet where a subsequent GOP header is detected out of TS packets having an identical PID.

5. The editing method according to claim 4 ,

wherein, in said detecting step, a sequence header and a sequence end code existing in a payload of a video PES packet are further detected.

6. A non-transitory computer readable recording medium with a computer program recorded thereon and comprising code that upon execution cause a computer to perform a transport stream encryption method, said method comprising the steps of:

detecting headers including at least a TS header, and a PES header of a PES packet existing in a payload of a TS packet, a GOP header existing in a payload of a video PES packet from an input transport stream which is not encrypted;

encrypting a remaining part of the input transport stream except at least the headers which are detected and storing an encrypted transport stream, which includes the headers not being encrypted and the remaining part being encrypted, into a storage device through a general-purpose bus;

receiving the encrypted transport stream from the storage device through the general-purpose bus;

restoring a moving picture from the encrypted transport stream; and

generating representative images corresponding to all or a part of GOPs respectively from the restored moving picture and storing the representative images to the storage device together with time codes which are related to the representative images;

transport stream editing method, comprising the steps of:

detecting the headers from the encrypted transport stream stored in the storage device;

editing the encrypted transport stream without decryption in such a way as to include a GOP selected by a user with reference to representative images in units of TS packets ranging from a TS packet where the GOP header is detected to a TS packet previous to a TS packet where a subsequent GOP header is detected out of TS packets having an identical PID; and

detecting the headers, a sequence header and a sequence end code existing in the payload of the video PES packet are further detected.