VIDEOTAPE INDEXING SYSTEM

Abstract: The system creates an index of video stored on a videotape. It includes a video recorder which generates a video signal that corresponds to the video stored on the videotape, and which adds an index marker to the videotape in response to a command. A computing device receives the video signal from the video recorder, detects a predetermined feature based on the video signal, issues the command to the video recorder to add the index marker to the videotape at a location of the predetermined feature, and stores the index marker. The computing device also issues a second command to the video recorder to forward the videotape to a particular location, which command includes an index marker which specifies the location. The video recorder receives this second command and, in response, searches through the videotape for the index marker included in the second command, and forwards the videotape to the location of the index marker.

Description: Videotape indexing system. BACKGROUND OF THE INVENTION Field Of The Invention The present invention is directed to system which maintains an index of information stored on videotape or other recordable media, and which uses that index to locate information on the videotape automatically. The system includes a video recorder which adds index markers (e.g., AVASS≡ pulses) to specific locations of the videotape, and a computing device (e.g., a personal computer) which stores these index markers in memory, together with identification information corresponding thereto. The personal computer is used to retrieve one of these index markers from memory based, e.g., on the identification information, and to command the video recorder to forward the videotape to a specific location identified by the index marker. Description Of The Related Art Information stored on digital storage media, such as digital video disks (ADVDss) and compact disks (ACDss), can be accessed rather easily due to direct addressing. Unfortunately, this is not the case for information stored on analog storage media, and in particular VHS videotape which comprises most home video libraries and other non- indexed material. More specifically, in order to access information stored on videotape, it is necessary to scroll through the videotape until the desired information is reached. When videotape was first introduced, this process was especially tedious, since there was no way to differentiate the information stored on the videotape. Rather, it was necessary to view the videotape, and to scroll through the tape manually (e.g., in Afast- forward≡ mode) in order to reach the desired information. Recognizing the inefficiency of this process, engineers developed improved ways of accessing information stored on videotape. For example, the VHS Index Search System (AVISS≡) places an electronic marker at the beginning of each new recording session (e.g., television program, home movie, video clip, or the like) on a videotape. A video recorder which recognizes these electronic markers can thus scroll from the beginning of one clip to the beginning of another clip with relative ease. While VISS markers constitute an advancement in the art, they have their drawbacks. For example, VISS markers do not identify information stored at each marker. As a result, they are of limited value, particularly if a user is unsure as to what is stored on the videotape. Moreover, it is inconvenient to use VISS markers to access intermediary portions of a video clip, since VISS markers must be inserted manually at the intermediary portions (as opposed to the beginning, where they are inserted automatically). For these reasons, conventional videotape indexing systems that rely on VISS markers have not proven wholly satisfactory. Accordingly, there exists a need for an improved videotape indexing system. In particular, there exists a need for a videotape indexing system which can identify video clips stored on a videotape, and which can access a video clip, or intermediary portions thereof, automatically. SUMMARY OF THE INVENTION The present invention addresses the foregoing needs. In particular, the invention is a system comprised of a computing device, such as a personal computer, and a video recorder. In operation, the video recorder adds index markers, preferably VASS pulses, to locations of the videotape in response to commands from the personal computer. The personal computer stores these index markers, together with information which identifies portions of video (e.g., video clips) on the videotape that correspond to the index markers. To access a selected portion of video, the personal computer retrieves an index marker therefor based, e.g., on its identification information, and sends a command to the video recorder instructing the video recorder to forward the videotape to the location of the index marker. The video recorder then responds accordingly, giving the user access to the selected video portion. Accordingly, unlike its conventional counterparts, the present invention is both able to identify video (e.g., video clips) on a videotape and, once a portion of video has been selected, to access that portion automatically. Moreover, by using VASS pulses, which can be added to a videotape at each video scene change, the invention provides a way to access intermediary portions of video clips on the videotape. For at least these reasons, the invention constitutes an advancement over its conventional counterparts. Thus, according to one aspect, the present invention is a system (e.g., a method, an apparatus, and computer-executable process steps) for creating an index of video stored on a videotape. In operation, the system detects a predetermined feature in the video, and then adds a unique index marker, preferably a VASS pulse, to the videotape at a location of the predetermined feature. The index marker is then stored in memory. In preferred embodiments, the invention also stores identification information together with this index marker. In this way, the invention is able to associate each index marker, and thus each portion of video on the videotape, with corresponding identification information. As a result, the index markers can be retrieved from memory using this identification information. In particularly preferred embodiments, the foregoing predetermined feature of the video comprises a scene change. In these embodiments, scene changes are detected by determining a difference between adjacent frames of the video, and comparing the difference to a predetermined threshold. When the difference meets or exceeds the predetermined threshold, a scene change is detected. On the other hand, when the difference is below the predetermined threshold, a scene change is not detected. Adding the index markers at scene changes provides the invention with greater indexing flexibility than its conventional counterparts. That is, unlike its conventional counterparts which rely on VISS pulses, the present invention can add index markers at intermediary portions of video. According to another aspect, the present invention is a system for accessing portions of video stored on a videotape, where the videotape includes a plurality of pre-set index markers, preferably VASS pulses. In operation, the system inputs an index marker that corresponds to one of the plurality of pre-set index markers on the videotape, and then searches through the videotape for a pre-set index marker that corresponds to the input index marker. The videotape is then forwarded to a location of the pre-set index marker that corresponds to the input index marker. According to still another aspect, the present invention is an apparatus, such as a personal computer, for creating an index of video stored on a videotape. The apparatus includes a processor and a memory which stores computer-executable process steps. The processor executes the process steps so as (i) to detect a predetermined feature in the video, (ii) to issue a command to a video recorder to add a unique index marker, preferably a VASS pulse, to the videotape at a location of the predetermined feature, and (iii) to store the index marker in memory. According to still another aspect, the present invention is an apparatus, such as a video recorder, for accessing portions of video stored on a videotape, which videotape includes a plurality of pre-set index markers. The apparatus includes a control signal connection over which is received an index marker that corresponds to one of the plurality of pre-set index markers on the videotape. Also included in the apparatus is circuitry which searches through the videotape for a pre-set index marker that corresponds to the received index marker, and which controls the videotape to forward to a location of the pre-set index marker that to corresponds to the received index marker. According to still another aspect, the present invention is a system for creating an index of video stored on a videotape. The system includes a video recorder which generates a video signal that corresponds to the video stored on the videotape, and which adds a unique index marker to the videotape in response to a command. Also included in the system is a computing device which receives the video signal from the video recorder, which detects a predetermined feature based on the video signal, which issues the command to the video recorder to add the index marker to the videotape at a location of the predetermined feature, and which stores the index marker. This brief summary has been provided so that the nature of the invention may be understood quickly. A more complete understanding of the invention can be obtained by reference to the following detailed description of the preferred embodiment thereof in connection with the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows a system on which the present invention may be implemented, which includes a personal computer, a video recorder, and a television. Figure 2 shows the architecture of the personal computer. Figure 3 shows the architecture of the video recorder. Figure 4 shows process steps of the present invention for generating an index for a videotape in the video recorder. Figure 5 shows process steps of the present invention for accessing video on a videotape using an index therefor. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Figure 1 shows a system on which the present invention may be implemented. As shown, system 1 includes a computing device, a video recorder, and a display device. In preferred embodiments, the computing device comprises a personal computer (APC≡) and the display device comprises a video display device/monitor, such as a television; although other types of devices may be used in both cases. Accordingly, although the invention will be described herein with respect to a personal computer 2 and a television 4, the invention is not limited to use with this particular hardware. In brief, television 4 comprises a standard television capable of receiving analog video signals from video recorder 3 and of generating and displaying video based on those signals. Video recorder 3 comprises any device, such as a videocassette recorder (AVCR≡) or videotape player, which generates such video signals from videotape and which outputs those signals, in this case, to television 4 and PC 2. As described in detail below, video recorder 3 is also capable of adding, recognizing, and erasing index markers on the videotape and of controlling operation thereof in response to commands from PC 2. In this regard, PC 2 can comprise any type of device, such as an LBM7 compatible computer, an Apple7 computer, or the like, which can exchange signals with video recorder 3 in the manner described below. As shown in Figure 1, PC 2 includes control signal connection 5 (e.g., a data line, such as a parallel, serial, or I C port) and baseband analog connection 6, both of which interface to video recorder 3. PC 2 also includes display screen 7 for displaying information (including images/video) to a user, keyboard 9 for inputting text and user commands, mouse 8 for positioning a cursor on display screen 7 and for inputting user commands, disk drive 10 for reading from and writing to floppy disks installed therein, and CD-ROM drive 11 for accessing data stored on CD-ROM. Of course, PC 2 is not limited to use with these digital recording media; others may be used as well. Figure 2 shows the internal structure of PC 2. As shown, PC 2 also includes memory 12, display interface 14, keyboard interface 15, mouse interface 16, disk drive interface 17, CD-ROM drive interface 19, computer bus 20, random access memory (ARAMΞS) 21, analog-to-digital (AA/D≤) converter 22, frame grabber circuit 24, and processor 25. Processor 25 comprises a microprocessor, or the like, for executing applications 26 out of RAM 21. Memory 12 comprises a computer-readable medium, such as a computer hard disk and/or RAID (Aredundant array of inexpensive disks≡), for storing these applications. Among the applications stored in memory 12 is videotape indexer 27. Videotape indexer 27 is used in implementing the present invention, as described below. In addition to applications 26, memory 12 also stores data 29 and operating system 30. In preferred embodiments of the invention, operating system 30 is a windowing operating system; although other operating systems may be used. The applications stored in memory 12, including videotape indexer 27, alternatively may be stored on a floppy disk in disk drive 10 or a CD-ROM in CD-ROM drive 11. In this case, processor 25 uses disk drive interface 17 to access applications stored on floppy disk, and CD-ROM drive interface 19 to access applications stored on CD-ROM. o Wherever the applications are stored, their execution may be initiated using keyboard 9 or mouse 8, commands from which are transmitted to processor 25 via keyboard interface 15 and mouse interface 16, respectively. Output results from applications running on PC 2 may be processed by display interface 14 and then displayed to a user on display 7 or, in the case of output results from videotape indexer 27, output to video recorder 3 via control signal connection 5. In this regard, display interface 14 preferably comprises a display processor which forms images based on image data provided by processor 25, and which outputs those images to display 7. Regarding the remaining components of PC 2, A/D converter 22 is an analog-to-digital converter which digitizes an analog video signal received over baseband analog connection 6 in order to produce a digital video signal therefrom. Frame grabber circuit 24 inputs this digital video signal, generates frames of digital video based thereon, and provides these frames to processor 25 via bus 20 for processing by videotape indexer 27, as described below. In brief, videotape indexer 27 comprises computer-executable code (i.e., process steps) for creating an index of video stored on a videotape. To this end, videotape indexer 27 includes code to detect one or more predetermined features in the video, to issue a first command to a video recorder to add a unique index marker to the videotape at a location of the predetermined feature, and to store the index marker in a memory, such as memory 12. Videotape indexer 27 also comprises computer-executable code for using the foregoing index to select a portion of the video on the videotape. To this end, videotape indexer 27 includes code to retrieve an index marker from the index, and to issue a second command to the video recorder instructing the video recorder to locate the index marker on the videotape and to forward the videotape to the location of the index marker. A more detailed description of videotape indexer 27 is provided below. As shown in Figure 1, video recorder 3 includes control signal connection 5 and baseband analog connection 6 for interfacing to PC 2, and television connection 34 for interfacing with television 4. Television connection 34 is used to transmit analog video signals from video recorder 3 to television 4. Baseband analog connection 6 comprises an interface over which analog video signals are transmitted to PC 2, and control signal connection 5 comprises a bi-directional interface over which commands are received from, and other information is exchanged with, PC 2. Video recorder 3 also includes various control buttons 35. These control buttons include a play button, a fast-forward button, a re- wind button, a stop button, and program button, among others. Since the functions of these buttons are well known, detailed descriptions thereof are omitted. Figure 3 shows the architecture of video recorder 3. As shown, video recorder 3 includes, among other things, baseband analog interface 36, control signal interface 37, baseband analog interface 38, VASS pulse circuitry 39, video processing circuitry 40, and tape drive 41. Baseband analog interface 36 outputs signals to baseband analog connection 6, and baseband analog interface 38 inputs signals (e.g., video information to be recorded) from television 4. Control signal interface 37 receives and processes commands from PC 2, as well as commands received from an external device, such as a remote control. Tape drive 41 includes a mechanical portion which controls videotape movement and circuitry which reads information from the various tracks on a videotape. In particular, tape drive 41 includes an audio head which reads audio information from audio tracks of the videotape and which writes information thereto, a control track head which reads and writes control information (e.g., the VASS — VHS Address Search System — pulses described below) on a control track of the videotape, and a video head which reads and writes video information on a video track of the videotape. Video processing circuitry 40 generates an analog video signal from video information read by the video head in tape drive 41, and provides that analog video signal to PC 2 via baseband analog connection 6. Video processing circuitry 40 also writes video information to videotapes in tape drive 41. VASS pulse circuitry 39 writes and reads VASS pulses on the control track of an installed videotape in response to commands received from PC 2. These VASS pulses comprise the Aindex markers≡ of the preferred embodiment of the present invention. Using current technology, up to 10,000 VASS pulses, numbered 0 to 9999, may be written to a single control track of a single videotape. A detailed description of the technical aspects of VASS pulses is provided in ANSI/SMPTE Standard 12M-1995, the contents of which are hereby incorporated by reference into the subject application as if set forth herein in full. Figures 4 and 5 are flow diagrams showing process steps for implementing the present invention on the system of Figure 1. Specifically, Figure 4 shows creating a videotape index, and Figure 5 shows accessing portions of video on the videotape using the videotape index. Whether a step is performed on PC 2 (e.g., by videotape indexer 27) or on video recorder 3 is indicated in Figures 4 and 5 by A(PC)s or A(VTR)≡, respectively. Starting with Figure 4, in step S401 video recorder 3 generates an analog video signal from an installed videotape and provides that analog video signal to PC 2. More specifically, in the preferred embodiment of the invention, a video head in tape drive 41 reads o video information from a video track of the videotape, and then provides that video information to video processing circuitry 40. Using this video information, video processing circuitry 40 generates the analog video signal, and then outputs that analog video signal to PC 2 via baseband analog connection 6. In step S402, PC 2 receives the analog video signal via baseband analog connection 6, and processes the analog video signal to generate frames of video data therefrom. In particular, A/D converter 22 receives and digitizes the analog video signal, and frame grabber circuit 24 generates frames of video data using the digitized video signal. These frames of video data are then stored temporarily in a memory, such as memory 12 or RAM 21, from which they may be accessed by processor 25 or, more particularly, by videotape indexer 27 running on processor 25. In preferred embodiments of the invention, alternate frames may be stored in different memory banks (e.g., in different areas of a single memory or in different memory devices). For example, the first frame may be stored in bank 1, the second frame in bank 2, the third frame in bank 1, the fourth frame in bank 2, etc. Storing alternate frames of video in this manner facilitates access thereto by processor 25, and thereby increases the speed and efficiency of the system overall. In this regard, in step S403 videotape indexer 27 retrieves two adjacent frames of video from memory in order to detect predetermined features thereof. In preferred embodiments of the invention, these predetermined features comprise scene changes; although it should be noted that the invention is not limited to detecting scene changes. Step S403 detects a scene change in the video by determining differences between the adjacent frames of the video, and comparing the differences to a predetermined threshold. For example, step S403 may detect differences, such as differences in luminance, chromaticity, etc., in corresponding pixels of preceding or succeeding frames in time, and then compare these differences to a predetermined numerical value stored, e.g., in memory 12. One particular method that may be used to detect scene changes in step S403 is described in U.S. Patent Application No. 08/867,140, filed June 2, 1997, entitled ASignificant Scene Detection And Frame Filtering For A Visual Indexing Systems, the contents of which are hereby incorporated by reference into the subject application as if set forth herein in full. Next, in step S404, videotape indexer 27 issues a command to video recorder 3 over control signal connection 5, which instructs video recorder 3 to add a VASS pulse to the control track of the videotape at a location corresponding to a detected scene change. This is preferably done automatically, meaning without user intervention; although it may also be done in response to a user=s input as well. In addition, step S404 preferably instructs the video recorder to add VASS pulses that are numbered, so that various pulses on the videotape can be distinguished from one another. In step S405, the foregoing command is received by video recorder 3 via control signal connection 5, and provided to VASS pulse circuitry 39. In response to this command, VASS pulse circuitry 39 writes a numbered VASS pulse to the control track of the videotape. Meanwhile, in step S406 (which may be performed concurrently with step S405), PC 2 stores in memory the number of the VASS pulse written in step S405, together with the frame(s) of video corresponding thereto. In preferred embodiments of the invention, individual index markers are stored in temporary storage, such as RAM 21 and, when a list of index markers has been established, that list is stored in more permanent memory, such as memory 12. Processing then proceeds to step S407, which determines if there are any frames of video remaining to be processed. If there are, processing returns to step S403, whereafter the foregoing is repeated in order to generate, and to store in memory, an index for the video on the videotape, which index includes a list of VASS pulses for all detected scene changes in the video. On the other hand, if no frames remain, then processing proceeds to step S408. Step S408 determines whether to eliminate similar scenes and Auni-color≡ scenes from the videotape index generated above. In this regard, uni-color scenes are detected based on frame Asignatures≡ from various parts of the frame. This step is optional, and is performed by videotape indexer 27 in response, e.g., to a user input or predetermined setting. Thus, if step S408 determines that similar or uni-color scenes are not to be eliminated, processing proceeds to step S410. Otherwise, processing proceeds to step S409, in which VASS pulses corresponding to similar or uni-color scenes are eliminated from the videotape and the index. To this end, step S409 retrieves frames from memory 12, determines differences between adjacent retrieved frames, and compares these differences to a second threshold, which is lower than the first threshold used above in step S403. If the differences between two adjacent frames meet or exceed the second threshold, it is determined that the two frames do not comprise similar scenes, in which case VASS pulses corresponding thereto are not eliminated. On the other hand, if the differences are below this second threshold, it is determined that the two frames comprise similar scenes. In this case, a command is output from PC 2 to video recorder 3 via control signal connection 5. This command instructs the control head in tape drive 41 to search through the control track of the videotape and VASS pulse circuitry 39 to erase VASS pulses, by number, which correspond to similar or uni-color scenes. For example, if step S409 determines that VASS pulse number 570 is at the point of a similar or uni-color frame, a command is output to the control head to search through the videotape for VASS pulse number 570, and to VASS pulse circuitry 39 to erase that pulse. While the VASS pulses are being erased from the videotape, processor 25 also deletes, from the videotape index (i.e., from memory), those VASS pulses which were determined to correspond to similar or uni-color scenes. The VASS pulses and the index thereof may also be renumbered during this elimination process, if desired, so as to maintain continuity thereof. Once all undesired VASS pulses have been eliminated, and their numbers erased from the videotape index, processing proceeds to step S410. In step S410, a user may add identification information to the index, which is then stored along with each respective VASS pulse. Specifically, the user may retrieve the videotape index from memory, and then add this information thereto. The identification information may include, for example, a description of video on the videotape that corresponds to each VASS pulse. Of course, the invention is not limited to adding descriptive information. In fact, a user can add any information that the user wishes. Once all identification information has been added, processing ends. The videotape index generated by the steps of Figure 4 may be used to automatically access video stored on a videotape in the video recorder. Figure 5 shows steps for performing this process. To begin, a videotape having a stored index is inserted into the video recorder. In step S501, videotape indexer 27 retrieves the index for that videotape from memory in response to a user=s input via, e.g., keyboard 9. This can be done simply by querying the memory for a particular index/tape ID. (e.g., tape #XYZ), or by retrieving all indices stored in memory, displaying the indices on display 7, and then selecting the index for the installed videotape in response to the user=s input. The user may then select a VASS pulse from the selected index. To facilitate selection, identification information corresponding to each VASS pulse in the index is also displayed. Thus, the user may the select a VASS pulse that corresponds, e.g., to a particular television program, home movie, etc. In any event, once the appropriate VASS pulse has been selected, processing proceeds to step S502. In step S502, videotape indexer 27 issues a second command to video recorder 3 over control signal connection 5. This second command includes the numbered VASS pulse selected in step S501, together with instructions for the video recorder to forward the videotape to that VASS pulse on the videotape. In preferred embodiments of the invention, this second command may alternatively be input to video recorder 3 via a remote control device or the like. This second command is received by the video recorder in step S503. Next, in response to the second command, in step S504, tape drive 41 (in particular the control head) searches through the videotape for a VASS pulse that corresponds to the VASS pulse received with the second command, and controls the videotape to forward to a location of that VASS pulse. In particular, the control head Aknows≡ the current position of the videotape and then starts rewinding or fast-forwarding the tape, whichever is appropriate, while reading the videotape=s control head in order to detect the first VASS pulse. If the first detected VASS pulse number is greater than the VASS pulse number in the second command, the video recorder switches to, or continues in, rewind mode. On the other hand, if the first detected VASS pulse number is smaller than the VASS pulse number from the second command, the video recorder switches to, or continues in, fast-forward mode. Thereafter, the video recorder continues, in the appropriate mode, with the control head reading the VASS pulses until it reaches the VASS pulse from the second command. Once it reaches this pulse, the video recorder stops the tape at the location of the pulse. If, for some reason, that particular pulse is missing, the video recorder stops at the location of the next pulse. Thereafter, in step S505, the user may play the tape beginning at the appropriate location. The process then ends. At this point, it is noted that although the invention is described herein using various hardware circuitry in addition to computer code, the functions of much of this circuitry alternatively can be performed by computer code. For example, A/D converter 22 and frame grabber circuit 24 in PC 2 could be implemented, in part, as computer code; although hardware is preferred. Likewise, video processing circuitry 40 and VASS pulse circuitry 39 could also be implemented in one device, such as in a single discrete circuit or even in a microprocessor (not shown) executing appropriate computer code. Moreover, it is noted that certain of the functions described above which are executed by computer code could likewise be implemented using discrete hardware circuitry. For example, the foregoing steps relating to detection of scene changes could be implemented by appropriate hardware. Furthermore, it is noted that while the preferred embodiment of the invention utilizes VASS pulses as index markers, the invention is not necessarily limited to using VASS pulses. That is, the invention can use any type of unique (e.g., numbered) index marker that can be written to analog tape and subsequently tracked on that tape. Since this is the case, the invention is not necessarily even limited to the realm of videotape. That is, it could be used with any type of analog tape, such as audiotape, to which index markers can be written and on which such markers can be tracked. Finally it noted that the process steps shown in Figures 4 and 5 need not necessarily be executed in the exact order shown, and that the order shown is merely one way for the invention to operate. Thus, other orders of execution are permissible, so long as the functionality of the invention is substantially maintained. The present invention has been described with respect to a particular illustrative embodiment. It is to be understood that the invention is not limited to the above-described embodiment and modifications thereto, and that various changes and modifications may be made by those of ordinary skill in the art without departing from the spirit and scope of the appended claims.

Claims: CLAIMS: 1. A method of creating an index of video stored on a videotape, the method comprising the steps of: detecting a predetermined feature in the video; adding an index marker to the videotape at a location of the predetermined feature; and storing the index marker in memory. 2. A method according to Claim 1, wherein the predetermined feature comprises a scene change in the video. 3. A method according to Claim 2, wherein the detecting step detects a scene change in the video by (i) determining a difference between adjacent frames of the video, and (ii) comparing the difference to a predetermined threshold, wherein the detecting step detects a scene change in a case that the difference meets or exceeds the predetermined threshold, and wherein the detecting step does not detect a scene change in a case that the difference is below the predetermined threshold. 4. A method according to Claim 1, wherein the index marker comprises a VASS pulse. 5. A method according to Claim 1, wherein the adding step is performed in response to a user input. 6. A method according to Claim 1, wherein the storing step further comprises storing identification information along with the index marker. 7. A method according to Claim 6, wherein the identification information comprises a description of video on the videotape that corresponds to the index marker. 8. A method according to Claim 1, wherein the detecting and storing steps are performed on a personal computer and the adding step is performed on a video recorder. 9. A method of accessing portions of video stored on a videotape, where the videotape includes a plurality of pre-set index markers, the method comprising the steps of: inputting an index marker that corresponds to one of the plurality of pre-set index markers on the videotape; searching through the videotape for a pre-set index marker that corresponds to the input index marker; and forwarding the videotape to a location of the pre-set index marker that corresponds to the index marker. 10. A method according to Claim 9, wherein the input index marker and the plurality of pre-set index markers comprise VASS pulses. 11. A method according to Claim 9, wherein the inputting step comprises: retrieving a list of pre-stored index markers from memory, and selecting the index marker from the list. 12. A method according to Claim 9, wherein the inputting step is performed on a personal computer and the searching and forwarding steps are performed by a video recorder. 13. An apparatus for creating an index of video stored on a videotape, the apparatus comprising: a memory which stores computer-executable process steps; and a processor which executes the process steps so as (i) to detect a predetermined feature in the video, (ii) to issue a command to a video recorder to add an index marker to the videotape at a location of the predetermined feature, and (iii) to store the index marker in memory. 14. An apparatus according to Claim 13, further comprising: an interface over which an analog signal that corresponds to the video on the videotape is received from the video recorder; an analog-to-digital converter which digitizes the analog signal to produce a digital video signal; and a frame grabber circuit which generates frames of video based on the digital video signal, and which outputs the frames of video to the processor; wherein the processor detects the predetermined feature in the video based on the frames of the video. 15. An apparatus according to Claim 14, wherein the processor detects the predetermined feature by (i) determining a difference between adjacent frames of the video, and (ii) comparing the difference to a predetermined threshold; wherein the predetermined feature is detected in a case that the difference meets or exceeds the predetermined threshold, and the predetermined feature is not detected in a case that the difference is below the predetermined threshold. 16. An apparatus according to Claim 13, wherein the predetermined feature comprises a scene change in the video. 17. An apparatus according to Claim 13, wherein the index marker comprises a VASS pulse. 18. An apparatus according to Claim 13, wherein the processor issues the command in response to a user input. 19. An apparatus according to Claim 13, wherein the processor executes process steps so as to store identification information along with the index marker. 20. An apparatus according to Claim 19, wherein the identification information comprises a description of video on the videotape corresponding to the index marker. 21. An apparatus according to Claim 13, wherein the processor executes process steps so as (i) to retrieve the index marker from memory, and (ii) to issue a second command to the video recorder instructing the video recorder to locate the index marker on the videotape and to forward the videotape to the location of the index marker. 10 22. An apparatus according to Claim 21, wherein the processor retrieves the index marker by (i) retrieving a list comprised of plural index markers from memory, (ii) displaying the list, and (iii) retrieving the index marker in response to a user selection from the list. 23. An apparatus according to Claim 13, wherein the apparatus is a personal computer. 24. An apparatus for accessing portions of video stored on a videotape, where the videotape includes a plurality of pre-set index markers, the apparatus comprising: an interface over which an index marker is received that corresponds to one of the plurality of pre-set index markers on the videotape; and circuitry which searches through the videotape for a pre-set index marker that corresponds to the received index marker, and which controls the videotape to forward to a location of the pre-set index marker that corresponds to the received index marker. 25. An apparatus according to Claim 24, further comprising circuitry which, prior to receiving the index marker, adds the plurality of pre-set index markers to the videotape in response to commands received from an external device. 26. An apparatus according to Claim 24, wherein the received index marker and the plurality of pre-set index markers comprise VASS pulses. 27. An apparatus according to Claim 24, wherein index marker is received over a data line from a personal computer. 28. An apparatus according to Claim 24, wherein the apparatus is a video recorder. 29. Computer-executable process steps stored on a computer-readable medium, the computer-executable process steps to create an index of video stored on a videotape, the computer-executable process steps comprising: code to detect a predetermined feature in the video; code to issue a command to a video recorder to add an index marker to the videotape at a location of the predetermined feature; and code to store the index marker in memory. 30. Computer-executable process steps according to Claim 29, wherein detecting code detects the predetermined feature by (i) determining a difference between adjacent frames of the video, and (ii) comparing the difference to a predetermined threshold; wherein the predetermined feature is detected in a case that the difference meets or exceeds the predetermined threshold, and the predetermined feature is not detected in a case that the difference is below the predetermined threshold. 31. Computer-executable process steps according to Claim 29, wherein the predetermined feature comprises a scene change in the video. 32. Computer-executable process steps according to Claim 29, wherein the index marker comprises a VASS pulse. 33. Computer-executable process steps according to Claim 29, wherein the issuing code issues the command in response to a user input. 34. Computer-executable process steps according to Claim 29, wherein the storing code stores identification information in memory along with the index marker. 35. Computer-executable process steps according to Claim 29, wherein the identification information comprises a description of video on the videotape corresponding to the index marker. 36. Computer-executable process steps according to Claim 29, further comprising: code to retrieve the index marker from memory; and code to issue a second command to the video recorder instructing the video recorder to locate the index marker on the videotape and to forward the videotape to the location of the index marker. 37. Computer-executable process steps according to Claim 36, wherein the retrieving code comprises: code to retrieve a list comprised of plural index markers from the memory; code to display the list, and lo code to retrieve the index marker in response to a user selection from the list. 38. A system for creating an index of video stored on a videotape, the system comprising: a video recorder which generates a video signal that corresponds to the video stored on the videotape, and which adds an index marker to the videotape in response to a command; and a computing device which receives the video signal from the video recorder, which detects a predetermined feature based on the video signal, which issues the command to the video recorder to add the index marker to the videotape at a location of the predetermined feature, and which stores the index marker. 39. A system according to Claim 38, wherein the computing device issues a second command to the video recorder to forward the videotape to a particular location, the command including an index marker which specifies the location; and wherein the video recorder receives the second command from the computing device, and in response, (i) searches through the videotape for the index marker included in the second command, and (ii) forwards the videotape to the location of the index marker. 40. A system according to Claim 38, wherein the predetermined feature comprises a scene change in the video. 41. A system according to Claim 38, wherein the index marker comprises a VASS pulse. 42. A system according to Claim 38, wherein the videotape includes plural tracks, one of which comprises a control track; and wherein the VASS pulse is added to the control track by the video recorder. 43. An apparatus for accessing portions of video stored on a videotape, where the videotape includes a plurality of pre-set index markers, the apparatus comprising: means for receiving an index marker that corresponds to one of the plurality of pre-set index markers on the videotape; means for searching through the videotape for a pre-set index marker that corresponds to the received index marker; and means for controlling the videotape to forward to a location of the pre-set index marker that to corresponds to the received index marker.

Inventors: LEYVI EVGENIY, LEYVI, EVGENIY
Applicants: KONINKL PHILIPS ELECTRONICS NV, KONINKLIJKE PHILIPS ELECTRONICS N.V.
Application year: 1999
Main classification: G11B27
IPC codes: G11B27, H04N5