Method for recording a digital broadcast program and time-based playback of a recorded broadcast program and apparatus therefor

• US 20030081939A1
• Filed: 09/27/2002
• Published: 05/01/2003
• Est. Priority Date: 10/29/2001
• Status: Active Grant

• Current Assignee: Humax Company Limited
• Original Assignee: Humax Company Limited
• Inventors: Lee, Bang Hyun, Kim, Jong Soon
• Granted Patent: US 8,045,843 B2
• Time in Patent Office: Days
• US Class Current: 386/67
• CPC Class Codes: G11B 2220/20 Disc-shaped record carriers
• CPC Class Codes: G11B 27/005 Reproducing at a different information rate from the information rate of recording for television signals H04N5/783
• CPC Class Codes: G11B 27/034 on discs G11B27/036, G11B27/038 take precedence
• CPC Class Codes: G11B 27/105 of operating discs
• CPC Class Codes: G11B 27/329 on a disc [VTOC]
• CPC Class Codes: H04N 21/4334 Recording operations recording of a television signal H04N5/76; arrangements for recording or accumulating broadcast information or broadcast-related information H04H60/27
• CPC Class Codes: H04N 21/8455 involving pointers to the content, e.g. pointers to the I-frames of the video stream
• CPC Class Codes: H04N 5/76 Television signal recording
• CPC Class Codes: H04N 5/781 on disks or drums
• CPC Class Codes: H04N 9/8042 involving data reduction

Abstract

A method and apparatus for receiving and recording a digital broadcast program and reproducing a recorded digital broadcast program with time-based trick play features. While recording a broadcast program on a storage medium, the apparatus creates an index file regarding random access points of the program. Receiving a request for a jump or trick play operation given in terms of time, the apparatus detects the time interval between each of the random access points based on the created file. Referring to the time interval, the apparatus determines the position to be reached by the jump and begins playback from the position or determines the number of access points to be skipped for the trick play and begins the requested trick play by skipping random access points by the number, thereby providing a user-friendly interface having time-based trick play features.

Claims

1. A method for recording a digital broadcast program, comprising the steps of:

(a) selecting a program composed of packets from received digital broadcast programs;

(b) recording said selected program onto a storage medium while outputting said selected program; and

(c) detecting data access points contained in said packets and storing the position index of each of said data access points in a file.

2. The method set forth in claim 1, wherein said step (c) detects said data access points based on a flag included in a header of each packet being recorded, the flag indicating start of an MPEG-defined PES (Packetized Elementary Stream) packet.

3. The method set forth in claim 2, wherein said step (c) detects whether each interval between successive data access points corresponds to a picture or an MPEG-defined GOP (Group of Pictures) based on the average of time intervals or amounts of data between successive data access points.

4. The method set forth in claim 3, wherein an interval between successive data access points corresponds to a field or a frame.

5. The method set forth in claim 4, wherein said step (c), if said interval corresponds to a picture, stores additional information indicative of a type of each data unit that corresponds to the interval between adjacent two data access points in association with each position index of the related data access point, the type being either an I-picture or a non-I-picture and said additional information being obtained based on the time intervals or amounts of data between successive data access points.

6. The method set forth in claim 1, wherein each interval between successive data access points corresponds to an MPEG-defined GOP.

7. The method set forth in claim 1, wherein said step (c) further comprises the step of calculating a presentation time interval between successive data access points based on a type of each data unit that corresponds to an interval between adjacent two successive data access points and adding the calculated presentation time interval to a set of the position indices, the type being either a picture or an MPEG-defined GOP.

8. The method set forth in claim 7, wherein said step (c) detects the number of pictures contained in a GOP by decoding the GOP and calculates said presentation time interval based on the detected number, if each interval between successive data access points corresponds to a GOP.

9. The method set forth in claim 7, wherein said step (c) names the file differently based on whether the data access point is inserted every picture or every MPEG-defined GOP.

10. A method for reproducing a digital broadcast program, comprising the steps of:

(a) receiving a time interval to jump from a present position on a recorded broadcast program;

(b) determining a position index of a data access point distant as far as the received time interval from the present position, based on position indexes for all data access points that are stored for the broadcast program and a presentation time of data between successive data access points; and

(c) decoding and outputting packets starting from a packet pointed by the determined position index or a packet near the pointed packet.

11. The method set forth in claim 10, wherein the presentation time is calculated based on whether the data access point has been created every picture or every MPEG-defined GOP.

12. The method set forth in claim 10, wherein said step (b) further comprises the step of detecting whether the data access point has been created every picture or every MPEG-defined GOP.

13. The method set forth in claim 12, wherein said step (b) detects whether the data access point has been created every picture or every MPEG-defined GOP, based on a name of a file storing a set of position indices of the data access points.

14. The method set forth in claim 13, wherein said step (c), if the data access point has been created every picture, decodes and outputs packets starting from a packet pointed by the determined position index if the determined position index is related to an I-picture, and otherwise from a packet pointed by an I-picture-related position index closest to the determined position index.

15. The method set forth in claim 10, wherein said step (b), if the received time interval to jump reaches a different program, detects a position index of a data access point distant as much as the received time interval from the present position by additionally referring to position indices of all data access points and a presentation time of data between successive data access points that are stored for the different program.

16. A method for reproducing a digital broadcast program, comprising the steps of:

(a) receiving a desired playback speed for a recorded program;

(b) determining the number of position indices of data access points to be skipped to meet the playback speed, based on a set of position indices of data access points and a presentation time of data between successive data access points that are stored for the recorded program; and

(c) repeating a process of selecting a position index after skipping as many position indices as the determined number and decoding and outputting a picture from a packet pointed by the selected position index or a packet near the pointed packet.

17. The method set forth in claim 16, wherein said step (c), in case that the data access point has been created every picture, decodes and outputs a picture from a packet pointed by the selected position index if the selected position index is related to an I-picture, and otherwise from a packet pointed by an I-picture-related position index closest to the selected position index.

18. The method set forth in claim 16, wherein the presentation time is calculated based on whether the data access point has been created every picture or every MPEG-defined GOP.

19. An apparatus for receiving a digital broadcast program, comprising:

selecting means for selecting a program from received digital broadcast programs;

output means for decoding and outputting packets constituting said selected program;

recording means for recording packets constituting said selected program on a storage medium; and

search information creating means for detecting data access points contained in said packets and recording every position index of the detected data access points in a file.

20. The apparatus set forth in claim 19, wherein said search information creating means detects the data access points based on a flag included in a header of each packet being recorded, the flag indicating start of a MPEG-defined PES packet.

21. The apparatus set forth in claim 20, wherein said search information creating means detects whether each interval between successive data access points corresponds to a picture or an MPEG-defined GOP (Group of Pictures) based on the average of time intervals or amounts of data between successive data access points.

22. The apparatus set forth in claim 19, wherein said search information creating means further performs a process of calculating a presentation time interval between successive data access points based on a type of each data unit that corresponds to an interval between adjacent two successive data access points and adding the calculated presentation time interval to a set of the position indices, the type being either a picture or an MPEG-defined GOP.

23. The apparatus set forth in claim 22, wherein said search information creating means detects the number of pictures contained in a GOP by decoding the GOP and calculates a presentation time interval between successive ones of said access points based on the detected number, if each interval between successive data access points corresponds to a GOP.

24. An apparatus for receiving a digital broadcast program, comprising:

storage means for storing a broadcast program and search information including a set of position indices of data access points of the broadcast program and a presentation time of data between successive data access points;

output means for decoding and outputting the stored broadcast program; and

control means for receiving a time interval to jump from a present position on the stored broadcast program, determining a position index of a data access point distant as far as the received time interval based on the search information, and providing packets starting from a packet pointed by the determining position index or a packet near the pointed packet for said output means so that the packets are decoded and outputted.

25. An apparatus for receiving a digital broadcast program, comprising:

storage means for storing a broadcast program and search information including a set of position indices of data access points of the broadcast program and a presentation time of data between successive data access points;

output means for decoding and outputting the stored broadcast program; and

control means for receiving a desired playback speed for the stored broadcast program, determining the number of position indices of data access points to be skipped to meet the playback speed based on the search information, and repeating a process of selecting a position index after skipping as many position indices as the determined number and providing at least one picture data from a packet pointed by the selected position index or a packet near the pointed packet for said output means so that the picture data is decoded and outputted.