# US 5,708,846 A · System for retrieving initial data sequence corresponding to next data sequence while locating next data sequence when branch point is reached during current data sequence > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,708,846 A - Document ID: US5708846A - Status: Granted - Kind: A - Application number: 08/394,156 - Filed: 1995-02-24 - Granted: 1998-01-13 - Earliest claimed: 1995-02-24 - Assignees: Intel Corporation - Inventors: Lawrence D. Ryan - Web page: https://patentgrep.com/patent/US5708846A ## CPC - H04N 7/17336: {Handling of requests in head-ends} - G11B 27/105: {of operating discs} - H04N 7/24: Systems for the transmission of television signals using pulse code modulation (H04N21/00 takes precedence) - G11B 2220/213: Read-only discs - G11B 2220/2545: CDs - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION - G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R) ## Abstract A method and apparatus for branching among a plurality of data sequences received from a relatively high latency mass storage device. According to a preferred embodiment, a plurality of initial data sequences respectively representative of the initial portions of data sequences of the plurality of data sequences are retrieved from the mass storage device, wherein the length of each initial data sequence is selected in accordance with the latency of the mass storage device. The plurality of initial data sequences is stored in a storage device having a low latency relative to the mass storage device. There is determined a next data sequence to be retrieved from the mass storage device when a branch point is reached during a current data sequence. The initial data sequence corresponding to the next data sequence is retrieved from the low latency storage device while the high latency mass storage device locates the next data sequence. ## Claims ### Claim 1 A method for branching among a plurality of data sequences received from a relatively high latency mass storage device, the method comprising the steps of: (a) retrieving from the mass storage device a plurality of initial data sequences respectively representative of the initial portions of data sequences of the plurality of data sequences, wherein the length of each initial data sequence is selected in accordance with the latency of the mass storage device; (b) storing the plurality of initial data sequences in a storage means having a low latency relative to the mass storage device; (c) determining a next data sequence to be retrieved from the mass storage device when a branch point is reached during a current data sequence; and (d) retrieving from the storage means the initial data sequence corresponding to the next data sequence while the mass storage device locates the next data sequence. ### Claim 2 (depends on 1) The method of claim 1, wherein the next data sequence is determined in accordance with input received from a user at or before the branch point. ### Claim 3 (depends on 1) The method of claim 1, wherein the mass storage device comprises a compact disk read-only memory drive which reads a compact disk that stores the plurality of data sequences. ### Claim 4 (depends on 3) The method of claim 3, wherein the compact disk comprises an initial sector that stores the plurality of initial data sequences and a data sector that stores the plurality of data sequences. ### Claim 5 (depends on 1) The method of claim 1, wherein the storage means comprises a hard disk drive. ### Claim 6 (depends on 1) The method of claim 1, wherein the storage means comprises random-access memory. ### Claim 7 (depends on 1) The method of claim 1, wherein: each data sequence represents a video sequence comprising a plurality of video frames; and each initial data sequence represents an initial video sequence representative of a subset of the plurality of video frames of the corresponding video sequence. ### Claim 8 (depends on 1) The method of claim 1, wherein the length of each initial data sequence is approximately equal to the maximum latency of the mass storage device. ### Claim 9 (depends on 1) The method of claim 1, wherein the length of each respective initial data sequence is approximately equal to the maximum latency of the mass storage device solely with respect to branching to the data sequence corresponding to each respective initial data sequence. ### Claim 10 (depends on 1) The method of claim 1, wherein the entire plurality of initial data sequences are retrieved from the mass storage device and stored in the storage means prior to retrieving any complete data sequences from the mass storage device. ### Claim 11 (depends on 1) The method of claim 1, wherein a second plurality of initial data sequences are retrieved from the mass storage device from a data subsequence and stored in the storage means while retrieving a current data sequence from the mass storage device, wherein the second plurality of initial data sequences are a subset of the plurality of initial data sequences and are respectively representative of the initial portions of a second plurality of data sequences that may be branched to from the current data sequence. ### Claim 12 (depends on 1) The method of claim 1, wherein: each data sequence represents a video sequence comprising a plurality of video frames; each initial data sequence represents an initial video sequence representative of a subset of the plurality of video frames of the corresponding video sequence; the mass storage device comprises a compact disk read-only memory drive which reads a compact disk that stores the plurality of data sequences; the compact disk comprises an initial sector that stores the plurality of initial data sequences and a data sector that stores the plurality of data sequences; the storage means comprises a hard disk drive; the next data sequence is determined in accordance with input received from a user at or before the branch point; the length of each initial data sequence is approximately equal to the maximum latency of the mass storage device; and the entire plurality of initial data sequences are retrieved from the mass storage device and stored in the storage means prior to retrieving any complete data sequences from the mass storage device. ### Claim 13 An apparatus for branching among a plurality of data sequences received from a relatively high latency mass storage device, the apparatus comprising: (a) means for retrieving from the mass storage device a plurality of initial data sequences respectively representative of the initial portions of data sequences of the plurality of data sequences, wherein the length of each initial data sequence is selected in accordance with the latency of the mass storage device; (b) means for storing the plurality of initial data sequences in a storage means having a low latency relative to the mass storage device; (c) means for determining a next data sequence to be retrieved from the mass storage device when a branch point is reached during a current data sequence; and (d) means for retrieving from the storage means the initial data sequence corresponding to the next data sequence while the mass storage device locates the next data sequence. ### Claim 14 (depends on 13) The apparatus of claim 13, wherein means (c) determines the next data sequence in accordance with input received from a user at or before the branch point. ### Claim 15 (depends on 13) The apparatus of claim 13, wherein the mass storage device comprises a compact disk read-only memory drive which reads a compact disk that stores the plurality of data sequences. ### Claim 16 (depends on 15) The apparatus of claim 15, wherein the compact disk comprises an initial sector that stores the plurality of initial data sequences and a data sector that stores the plurality of data sequences. ### Claim 17 (depends on 13) The apparatus of claim 13, wherein the storage means comprises a hard disk drive. ### Claim 18 (depends on 13) The apparatus of claim 13, wherein the storage means comprises random-access memory. ### Claim 19 (depends on 13) The apparatus of claim 13, wherein: each data sequence represents a video sequence comprising a plurality of video frames; and each initial data sequence represents an initial video sequence representative of a subset of the plurality of video frames of the corresponding video sequence. ### Claim 20 (depends on 13) The apparatus of claim 13, wherein the length of each initial data sequence is approximately equal to the maximum latency of the mass storage device. ### Claim 21 (depends on 13) The apparatus of claim 13, wherein the length of each respective initial data sequence is approximately equal to the maximum latency of the mass storage device solely with respect to branching to the data sequence corresponding to each respective initial data sequence. ### Claim 22 (depends on 13) The apparatus of claim 13, wherein the entire plurality of initial data sequences are retrieved from the mass storage device and stored in the storage means prior to retrieving any complete data sequences from the mass storage device. ### Claim 23 (depends on 13) The apparatus of claim 13, wherein a second plurality of initial data sequences are retrieved from the mass storage device from a data subsequence and stored in the storage means while retrieving a current data sequence from the mass storage device, wherein the second plurality of initial data sequences are a subset of the plurality of initial data sequences and are respectively representative of the initial portions of a second plurality of data sequences that may be branched to from the current data sequence. ### Claim 24 (depends on 13) The apparatus of claim 13, further comprising: bus means electrically connected to the apparatus; and memory means electrically connected to the bus. ### Claim 25 (depends on 13) The apparatus of claim 13, wherein: each data sequence represents a video sequence comprising a plurality of video frames; each initial data sequence represents an initial video sequence representative of a subset of the plurality of video frames of the corresponding video sequence; the mass storage device comprises a compact disk read-only memory drive which reads a compact disk that stores the plurality of data sequences; the compact disk comprises an initial sector that stores the plurality of initial data sequences and a data sector that stores the plurality of data sequences; the storage means comprises a hard disk drive; means (c) determines the next data sequence in accordance with input received from a user at or before the branch point; the length of each initial data sequence is approximately equal to the maximum latency of the mass storage device; and the entire plurality of initial data sequences are retrieved from the mass storage device and stored in the storage means prior to retrieving any complete data sequences from the mass storage device. ### Claim 26 (depends on 25) The apparatus of claim 25, further comprising: bus means electrically connected to the apparatus; and memory means electrically connected to the bus.