Method and device for recording real-time information

• US 20040131332A1
• Filed: 12/17/2003
• Published: 07/08/2004
• Est. Priority Date: 11/16/1998
• Status: Active Grant

• Current Assignee: Patricia E.M. Wilson, Robert A. Brondijk
• Original Assignee: Patricia E.M. Wilson, Robert A. Brondijk
• Inventors: Wilson, Patricia E.M., Brondijk, Robert A.
• Granted Patent: US 7,283,723 B2
• Time in Patent Office: Days
• US Class Current: 386/68
• CPC Class Codes: G11B 2220/213 Read-only discs
• CPC Class Codes: G11B 2220/216 Rewritable discs
• CPC Class Codes: G11B 2220/218 Write-once discs
• CPC Class Codes: G11B 2220/2545 CDs
• CPC Class Codes: G11B 2220/2562 DVDs [digital versatile discs]; Digital video discs; MMCDs; HDCDs
• CPC Class Codes: G11B 2220/2575 DVD-RAMs
• 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 27/11 by using information not detectable on the record carrier
• CPC Class Codes: G11B 27/3027 used signal is digitally coded
• CPC Class Codes: G11B 27/329 on a disc [VTOC]
• CPC Class Codes: G11B 27/34 Indicating arrangements indicating means incorporated in magazine or cassette G11B23/046 and G11B23/0875; indicating measured values in general G01D
• CPC Class Codes: H04N 5/85 on discs or drums
• CPC Class Codes: H04N 9/8042 involving data reduction

Abstract

A method and device for recording real time information on a record carrier, e.g. video on an optical disc. The information is arranged according to a recording format, e.g. DVD video, for being playable in standardized players. The information is subdivided into units and playback parameters for reproducing sequences of the units are included in the units. The format prescribes forward pointers to units that are located at a large distance from the unit which includes the forward pointers. However for home recording it is required that a recording is made in one pass, i.e. the video is to be recorded directly at its final location without a large buffer. So the device has a small buffer (30), and a processing unit (20,28) for determining pointers to nearby units based on the buffer contents, while values for pointers pointing far forward are set arbitrarily, based on nearby units and/or default values indicating that the unit intended to be pointed to does not exist. Standard playback devices can still play the recorded material in trickplay modes with only minor deviations in the fast forward scanning speed.

Claims

1. Method of recording real time information and playback parameters related thereto on a record carrier arranged according to a recording format, in which method the real time information is subdivided into units and the playback parameters are generated and included in the units, which playback parameters comprise pointers to units located at a forward and/or backward distance relative to the unit in which the pointers are included, characterized in that the method comprises the steps of

buffering the real time information for a period before recording,

determining a value for at least one of said pointers based on the buffered real time information,

calculating a value for at least a further one of said pointers intended to point to a unit located at a forward distance larger than said period, based on the buffered real time information and/or a predefined value, and

recording the buffered real time information together with said determined and calculated values.

2. Method as claimed in claim 1, wherein, while said pointers comprise forward speed pointers to units located at predefined amounts of time forward for reproducing sequences of the units at different speeds, the value is calculated for forward speed pointers that are intended to point to units a larger amount of time forward than said period.

3. Method as claimed in claim 2, wherein the value is calculated to be indicative of the last unit within said period or is a predefined value indicative of the non-existence of the unit intended to be pointed to.

4. Method as claimed in claim 2, wherein the value is calculated to be indicative of the last unit within said period for a first predefined number of said forward speed pointers and is a predefined value indicative of the non-existence of the unit intended to be pointed to for a second predefined number of said forward pointers.

5. Method as claimed in claim 2, wherein, while said pointers further comprise backward speed pointers to units located at predefined amounts of time backward for reverse reproducing sequences of the units at different speeds, the values are calculated for the backward speed pointers similarly to the values calculated for the forward speed pointers.

6. Method as claimed in claim 1, wherein the recording format is the DVD format.

7. Device for recording real time information and playback parameters related thereto on a record carrier arranged according to a recording format, the recorder comprising processing means (20,28) for subdividing the real time information into units and for generating the playback parameters to be included in the units, which playback parameters comprise pointers to units located at a forward and/or backward distance relative to the unit in which the pointers are to be included, characterized in that the device comprises buffer means (30) for buffering the real time information for a period before recording, and in that the processing means (20,28) are arranged for

determining a value for at least one of said pointers based on the buffered real time information,

calculating a value for at least a further one of said pointers intended to point to a unit located at a forward distance larger than said period, based on the buffered real time information and/or a predefined value, and

recording the buffered real time information together with said determined and calculated values.

8. Device as claimed in claim 7, wherein, while said pointers comprise forward speed pointers (FWDIn in VOBU_SRI) to units located at predefined amounts of time forward for reproducing sequences of the units at different speeds, the processing means (20,28) are arranged for calculating values for forward speed pointers that are intended to point to units a larger amount of time forward than said period, the calculated value being the address of the last unit in the buffer or a predefined value (3F FF FF FF).

9. Device as claimed in claim 7, wherein the calculated values are indicative of the last unit within said period and/or a predefined value indicative of the non-existence of the unit intended to be pointed to.

10. Device as claimed in claim 7, wherein the recording format is the DVD format.

11. Device as claimed in claim 7, wherein the pointer is an audio synchronizing pointer (A_SYNCA in SYNCI) for which the calculated value is a default value or the buffer means (30) have a size to cover a period at least equal to a maximum skew between audio and video to enable determining value for the audio synchronizing pointer.

12. Device as claimed in claim 7, wherein the processing means (20,28) are arranged for generating fixed size cells (Cell,VOB) and the pointer is a playing time indicator (VOB_V_E_PTM) for which the value is calculated from said fixed size.