Recording medium for storing still pictures and a recording and/or reproducing method and apparatus

0001The present invention relates in general to recording and/or reproducing audio and/or video data using a rewriteable recording medium such as a DVD disk, and more particularly to a recording medium for storing and effectively processing a still picture and audio data added thereto, and recording and/or reproducing method and apparatus therefor.

0002Figure 1 shows a connection structure for various kinds of information in a moving picture and moving picture data, in recording/reproducing audio and/or video data on a recordable and/or rewriteable recording medium, specifically, a digital versatile disk (DVD), and more precisely, it illustrates the relationship between program chain (PGC) information 11 for treating data logically, moving picture information 12 consisting of video object (VOB) information, and a moving picture data file 13 in which actually compressed audio/video (A/V) data are recorded in VOB units.

0003First, terms used throughout the specification will now be described. Supposing a movie was recorded in first and second parts, the overall movie is a program chain (PGC) and the first and second parts are programs. Also, each program can be defined by further dividing the same into several cells called sub-units. The information in each cell can wholly or partially define a video object (VOB). In such an event, each cell is used as a basic accessing unit during reproduction, and the program and PGC are only the information for connectivity between a plurality of cells.

0004Also, since data is actually sub-divided into video object units (VOBUs) and recorded in a moving picture data file, the VOB information consists of various kinds of information relating to the VOBU data, that is, VOBU #1, VOBU #2,.... and the VOB data in the moving picture data file is accessed by the VOB information. Here, the VOB data is used as a random access unit of a disk recording/reproducing apparatus. The VOBU is based on a single GOP (Group of Pictures) in the case of an MPEG (Moving Picture Experts Group) video, and audio data corresponding to video data is collected, that is, A/V data is multiplexed into sectors, to constitute a VOBU.

0005The data format shown in Figure 1 is concerned with the moving picture, in which the unit of actual data, the VOB, comprises moving picture data for a fixed period of time. Synchronization or encoding of A/V signals is performed in units of VOBs. However, in the case of a still picture, each VOB constitutes a still picture. When a VOB is designated in a cell structure, a cell is necessary for each still picture. Thus, as more the still pictures are recorded, more information is added.

0006Generally, data errors may be generated if data is recorded on a recordable disk a predetermined number of times. Thus, there is a limit to the number of times data may be written on a disk without errors. All information is stored in the memory of a controller for controlling the system for the purpose of limiting the number of times recording is required and rapidly accessing data. However, as described above, in the case of a still picture, if the amount of information is increased, much time is required for reading the information. Also, there is a limit to the amount of information that can be stored in a memory with a limited size. Accordingly, it is not possible to record large-capacity still pictures.

0007It is an aim of a first aspect of the present invention to provide a recording medium for effectively storing large-capacity still pictures and preferably to provide easy management of the stored still pictures. Also, it is an aim to store video information for a still picture or video information for a still picture having audio data added thereto, and audio data, in the recording order of recorded bitstreams.

0008It is an aim of a second aspect of the present invention to provide a method for recording large-capacity still pictures in order to manage the still pictures and information related to reproduction, and for reproducing the still picture according to the recorded information. A preferred aim is to record video information for a still picture or video information for a still picture having audio data added thereto and audio data, and information related to reproduction, and for reproducing the still picture or the still picture having audio data added thereto according to the recorded information.

0009It is an aim of a third aspect of the present invention to provide an apparatus for recording large-capacity still pictures and audio data added thereto in order to manage the still pictures, and reproducing the still picture or both the still picture and the audio data added thereto according to the recorded information.

0010According to a first aspect of the present invention there is provided a recording medium as set forth in claim 1 appended hereto. The recording medium includes a first region having data for a plurality of still pictures, and a second region having still picture group information for separating the still picture data in the first region into a predetermined maximum number of groups in order to manage the still pictures at a group level.

0011Preferably, each of the first and second regions exists in the form of a separate file.

0012Preferably, the first region further includes audio data added to the still picture data.

0013Preferably, the still picture data and the audio data added thereto exist in one file.

0014Preferably, the still picture data and the audio data added thereto exist in a space having a logically one-dimensional order.

0015Preferably, the second region further includes information for managing the audio data.

0016Preferably, the second region further includes still picture general information containing the number of still picture groups.

0017Preferably, the still picture group information includes still picture group general information containing start position information of the still picture group and information relating to the number of video parts in the still picture group, and information for the respective still pictures, the information containing position information thereof.

0018Preferably, the still picture group general information further includes identification information of a still picture group.

0019Preferably, the position information for the respective still pictures includes size information of video parts.

0020Preferably, the position information for the respective still pictures further includes size information of audio parts for audio data for the still picture and playback time information thereof.

0021Preferably, the position information for the respective still pictures includes identification information of a still picture in a still picture group.

0022Preferably, the second region further stores playback information related to reproduction.

0023Preferably, the playback information includes identification information of a still picture group, and information for playback start and ending positions in the still picture group.

0024Preferably, the playback information is applied to all or some of the still picture groups.

0025According to a second aspect of the present invention there is provided a method for recording and/or reproducing audio and/or video data on a writeable and/or rewriteable recording medium as set forth in claim 16 appended hereto. The method includes the steps of (a) recording a plurality of input still pictures, and (b) separating the plurality of still pictures into a predetermined maximum number of groups, and recording still picture group information and playback information related to reproduction.

0026The method preferably further includes the steps of (c) reading still picture group information to be reproduced in accordance with the playback information, and (d) calculating the position of a desired still picture in accordance with the read still picture group information and reproducing the still picture data located at the calculated position.

0027According to a third aspect of the invention there is provided a reproduction method as set forth in claim 30 appended hereto. The method is for use with a recording medium comprising a first region having data for a plurality of still pictures, a second region having still picture group information for separating the still picture data in the first region into a predetermined maximum number of groups in order to manage the still pictures at a group level, the reproduction method comprising the step of reproducing the still picture data in the first region, based on the still picture group information in the second region.

0028According to a fourth aspect of the present invention there is provided an apparatus as set fourth in claim 37 appended hereto. The apparatus includes a recording processor for signal-processing a plurality of still pictures to be recorded in a first region on the recording medium, and a controller for generating still picture group information for separating still pictures in the first region into a predetermined maximum number of groups in order to manage the still pictures at a group level and playback information related to a reproduction order, and for controlling the generated information to be recorded in a second region.

0029Also, the apparatus may further include a playback processor for reproducing still picture data in the first region based on the still picture group information.

0030Other preferred features of the present invention will be apparent from the dependent claims and the detailed description which follows.

0031For a better understanding of the invention, and to show how embodiments of the same may be carried into effect, reference will now be made, by way of example, to the accompanying diagrammatic drawings in which: <ul id="ul0001" list-style="none"><li>Figure 1 illustrates a connection structure of various kinds of information and data in a moving picture;</li><li>Figure 2 shows an example of an overall information structure according to an embodiment of the present invention;</li><li>Figure 3 shows the relationship between various kinds of information and still picture data in a still picture according to an embodiment of the present invention;</li><li>Figure 4 is a block diagram of a recording/reproducing apparatus according to an embodiment of the present invention;</li><li>Figure 5 shows the relationship between still picture data and still picture group information according to an embodiment of the present invention;</li><li>Figure 6 shows the relationship between cell information and still picture group information;</li><li>Figure 7 illustrates the structure of still picture group information according to an embodiment of the present invention;</li><li>Figure 8 is a table showing an example of the detailed contents of the still picture group general information shown in Figure 7;</li><li>Figure 9 illustrates the structure of a still picture map table shown in Figure 7;</li><li>Figure 10 is a table showing an example of the detailed contents of a video map in the map table shown in Figure 9;</li><li>Figure 11 is a table showing an example of the detailed contents of an audio map connected to the video map shown in Figure 10;</li><li>Figure 12 is a table showing an example of the detailed contents of cell information for the still picture shown in Figure 6;</li><li>Figures 13A and 13B illustrate a flow chart showing a method for recording a still picture according to an embodiment of a present invention; and</li><li>Figure 14 is a flow chart showing a method for reproducing a still picture according to an embodiment of the present invention.</li></ul>

0032Hereinafter, preferred embodiments of recording media for storing the information for a still picture, and recording and/or reproducing method and apparatus therefor, will be described.

0033Figure 2 shows an example of an overall information structure according to the present invention, in which information comprising PGC information, moving picture information and still picture information can be recorded in an information file or an information area.

0034Here, PGC general information contains information such as the number of programs in a PGC. Program general information contains information such as the number of cells in a program. The cell information designates a VOB in the case of a moving picture, as shown in Figure 1, and designates a still picture VOB group (to be abbreviated as "still picture group" for brevity) instead of a VOB, in the case of a still picture, as shown in Figure 3. Since the moving picture information has already been described with reference to Figure 1, a description thereof will not be repeated here and still picture information according to an embodiment of the present invention will now be described. Still picture general information contains information relating to the number of kinds of still picture group information, and additional audio general information for the still picture contains information relating to the number of kinds of additional audio group information.

0035Figure 3 shows the connection structure of various kinds of information and still picture data in a still picture. In other words, in a still picture recorded in units of VOBs in a data file, a plurality of VOBs for still pictures are managed by a still picture group, and cell information contained in the PGC information 21 designates still picture group information (GVOB), rather than a single VOB information. Also, audio data may be recorded in addition to the still picture. The audio data is recorded consecutively after the still picture is recorded, thereby reducing the search time of a reproducing head during reproduction. The audio data recorded together with the still picture is called original audio data, which is contained in the still picture group. In the present invention, unless specifically defined, a still picture represents both one having only a video part and one having the original audio part and the video part.

0036By managing the still picture by grouping the same in such a manner, the amount of cell information and still picture information can be reduced. For example, video coding attributes or audio coding attributes in a still picture group are assimilated thus forming still picture group general information, and stored as common information. For the respective still pictures, the positions thereof in the still picture data file must be indicated. In the case when the still pictures are not separated into a plurality of groups, the start positions of the respective still pictures must be indicated. However, in the case when the still pictures are grouped, the start position at which the pertinent still picture group starts to be recorded in a file is stored in the still picture group general information and then only the sizes of the respective still pictures are recorded as the information for the respective still pictures. Since the amount of information indicative of the size of still picture data, i.e., the number of bytes, is generally less than that indicative of the position in a file, the overall amount of information can be reduced.

0037In order to locate a recording position of a specific still picture in the still picture group, the start position of the still picture group data contained in the still picture group general information is added to the size of the data preceding the still picture to be located. Also, in order to read audio data added to a still picture, the located position of the still picture is added to the size of video parts of the still picture.

0038In the case of a still picture group, video parts and audio parts are consecutively recorded in a file or space. Thus, the video information and the audio information each containing the size thereof are also recorded in a bitstream order in which the video data and the audio data are actually recorded. Thus, the respective regions shown in Figure 3 can exist in the form of still picture file 23 to which audio data may be added, and information file containing cell information contained in the PGC information 21 and still picture information 22. The still picture file 23 can be designated by a first region, and the information file containing the PGC information 21 and the still picture information 22 can be designated by a third region which is a logic region.

0039Figure 4 is a block diagram of a recording/reproducing apparatus for implementing the present invention. The function of an apparatus for recording/reproducing A/V (audio/video) data using a recordable and rewriteable disk is largely divided into recording and reproduction.

0040During recording, an AV codec 110 compression-codes an externally applied A/V signal by a predetermined compression scheme and supplies size information for compressed data. A digital signal processor (DSP) 120 receives A/V data supplied from the AV codec 110, adds additional data for ECC (error correction code) processing thereto and performs modulation using a predetermined modulation scheme. A radio frequency amplifier (RF AMP) 130 converts electrical data supplied from the DSP 120 into an RF signal. A pickup 140 drives a disk and records the RF signal supplied from the RF AMP 130, incorporating an actuator for focusing and tracking. A servo 150 receives information necessary for servo control from a system controller 160 and stably performs a servo function. The system controller 160 controls the overall system through interfacing with a user to thus control the still picture to be recorded on the disk and record separate information for the recorded still picture. Still picture data are managed at a group level by constructing the still picture group information of the information for the respective still pictures, including size information of still picture data, size information of audio data, playback time information of audio data and the like, and the position information of the respective still pictures, in the recording order of recorded still pictures and audio data. Cell information concerning the reproduction order is recorded as well as the above-described information. The cell information contains information indicative of the recorded still picture group so that the recorded still picture and audio data can be reproduced.

0041During playback, the pickup 140 picks up the optical signal from the disk having data stored therein and the data is extracted from the optical signal. The RF AMP 130 converts the optical signal into an RF signal, and extracts a servo signal for performing a servo function, and modulated data. The DSP 120 demodulates modulated data supplied from the RF AMP 130 corresponding to the modulation scheme used during modulation, performs an ECC process to correct errors and eliminates added data. The servo unit 150 receives information necessary for servo control from the RF AMP 130 and the system controller 160 and stably performs a servo function. The AV codec 110 decodes the compressed A/V data supplied from the DSP 120 to output an A/V signal. The system controller 160 controls the overall system for reproducing the user's desired data (still picture only, still picture + audio data or still picture + additional audio data) using the cell information and still picture group information stored on the disk while performing user interfacing such as processing of the user's key inputs.

0042In other words, in order to reproduce a specific still picture and audio data, the still picture group information having the still picture to be reproduced is obtained from the cell information, information such as the size of the still picture data and the information for the data size and playback time of audio data, if any, is obtained from the still picture group information, thereby reproducing only desired data. Here, the A/V codec 110, the DSP 120, the RF AMP 130 and the pickup 140 operating during recording can be referred to as a recording processor. Also, the pickup 140, the RF AMP 130, the DSP 120 and the A/V codec 110 operating during playback can be referred to a reproduction processor.

0043Figure 5 shows the relationship between still picture data and still picture group information, in which the information for a plurality of still pictures (e.g., 64 maximally) having the same attributes is recorded in the respective still picture group (GVOB) information 201. The number of the still pictures forming each still picture group is determined such that it is within the limit of the maximum number of still pictures. Each still picture group information 202 includes still picture group general information and information for the respective still pictures and is information for still picture data 203 composed of video parts and video or audio parts in a sequence of bitstreams recorded. The still picture group generation information has the start address of the corresponding still picture group.

0044Also, as information for the respective still pictures, still picture information having audio data exists in the form of map information composed of video part information for video parts and audio part information for audio parts. Here, a video map and an audio map for a still picture have the same identification information. If the still picture information is composed of only video parts, it exists in the form of a map having only the video part information. Here, still picture data is recorded in a VOB.

0045Figure 6 shows the relationship between cell information (which can also be referred to as playback information) and still picture group information, in which a cell is a logical unit in relation to indication of a reproduction order. The cell information includes still picture group identification information (GVOB_ID), still picture reproduction start identification information (START VOB_ID) of the corresponding still picture group and still picture reproduction ending identification information (END VOB_ID). The cell information may correspond to all the still picture groups or may correspond to some of still picture groups which are intended to be reproduced.

0046Figure 7 illustrates the structure of still picture group information according to the present invention, which includes still picture group general information and a still picture map table, and may further include attribute information for a still picture such as picture sizes or video encoding modes.

0047Figure 8 is a table showing an example of the detailed contents of still picture group general information shown in Figure 7, which includes GVOB_ID representing information for identifying a still picture group in a still picture file, GVOB_S_ADR representing the start address of first still picture data in the corresponding still picture group in the still picture file, GVOB_Ns representing the number of still pictures in the still picture group, and so on. Here, the identification information GVOB_ID can be expressly recorded as a unique one for each still picture group in a still picture file or can be suggestively indicated in the order of still picture groups, that is, #1, #2,...

0048Figure 9 illustrates the structure of the still picture map table shown in Figure 7. There are two types of maps; one is video maps VMAPs for video parts and the other is audio maps AMAPs for audio parts added to a still picture. The order of maps is the same as that of data of recorded bitstreams in a still picture file as shown in Figure 5. Thus, in the case when a still picture has only video parts, there are only video maps. In the case when a still picture has audio data in addition to the video parts, both video maps and audio maps are recorded and are practically considered as one map using the same identification information.

0049Figure 10 is a table showing an example of the detailed contents of a video map in the map table shown in Figure 9, containing MAP_TY indicating the type of a corresponding map and represented by a binary "0" in the case of a video map for video parts, VOB_ID indicating identification information for the video parts and ranging from 1 to 64 in preferred embodiments. Also, VOB_ID can be expressly indicated or suggestively indicated in the recording order, that is, #1, #2, #3,...

0050Also, the video map contains V_PART_SZ indicating the size of video parts. Here, VOB_ID and V_PART_SZ can be referred to as still picture position information.

0051Figure 11 is a table showing an example of the detailed contents of an audio map, containing MAP_TY indicating the type of a corresponding map and represented by a binary value "1" in the case of an audio map for audio parts, A_PSTM indicating the playback time of an audio part and A_PART_SZ indicating the size of an audio part.

0052Figure 12 is a table showing an example of the detailed contents of cell information for a still picture, shown in Figure 7, containing S_GVOB_ID indicating identification information for a still picture group, S_VOB_ID indicating identification information for a still picture in which reproduction starts, and E_VOB_ID indicating identification information for a still picture in which reproduction ends.

0053Figures 13A and 13B illustrate a flow chart showing a method for recording a still picture according to an embodiment of the present invention, that is, a method for recording a still picture and audio data. First, it is determined whether a still picture or both a still picture and audio data is recorded (step S101). Still picture group information is generated, identification for a still picture group is allocated, the number of still pictures in the still picture group is set to "0" and the start address of the still picture group in a still picture file is recorded (step S102). It is then determined whether a recording start signal of a still picture is input by a user or not (step S103). If the recording start signal is input, the still picture is recorded in the still picture file, identification information for the still picture is allocated to the still picture group information, the number of still pictures in the still picture group is increased by one and the size information of the still pictures is recorded in the video map (step S104).

0054It is determined whether or not a mode set by a user is for recording both a still picture and audio data (step S105). If yes, the audio data for the still picture is recorded following after the corresponding still picture on the still picture file and the audio size information is recorded in an audio map in the still picture group information (step S106).

0055It is determined whether the number of still pictures recorded is enough to constitute the information for a still picture group (e.g., 64 maximally) (step S107). If the still picture group information is completed, the procedure returns to step S102 to generate another still picture group information. Otherwise, the procedure proceeds to step S103 to determine whether a recording start signal of a still picture is input by a user or not.

0056If the mode set by a user is for recording only a still picture in step S105, step S106 is skipped and the procedure proceeds to step 107 to record the next still picture. If the recording start signal of a still picture is not input by a user in step S103, it is determined whether or not recording to terminate recording (step S108). If it is determined to terminate recording, cell information is recorded and the procedure ends (step S109). Here, the cell information is created for every still picture group so as for all still pictures to be reproduced.

0057Figure 14 is a flow chart showing a method for reproducing a still picture according to an embodiment of the present invention, that is, a method for reproducing a still picture and audio data added thereto. Referring to Figure 14, PGC information and cell information are read (step S201). Identification information for a still picture group to be reproduced, playback start identification information and playback ending identification information are read from the cell information to read the still picture group information pointed to by the cell (step S202). Video map information for the video part corresponding to the playback start identification information in the read still picture group information is obtained to read the size of a video part, or both video map information and audio map information are obtained in the case of a still picture having audio data to read the size of a video part and the size of an audio part (step S203).

0058The position of a desired still picture is calculated by the read video part information and video data located at the calculated position is read and decoded to reproduce the still picture (step S204). Here, the position of a desired still picture is obtained by summing the start position of a still picture group and the size of data preceding the desired still picture. While the still picture is reproduced, it is determined whether audio data is added to the still picture (step S205). If yes, the audio data is read and decoded to reproduce the audio data (step S206). Here, the reading position of the audio data is obtained by summing the calculated position of the still picture and the size of video parts of the still picture. It is checked whether all still pictures belonging to a cell are reproduced or not using the cell information and then it is determined whether or not there is a still picture to be reproduced next (step S207). If yes, the information for the video part of a still picture to be reproduced next is read (step S203). Otherwise, the procedure is terminated. In the case when there are a plurality of series of cell information, this routine is repeated.

0059Here, the step of determining whether audio data is added to a still picture (step S205) may be performed directly after the step of reading the still picture group information (step S202). This is because it is possible to determine that audio data is added to a still picture in the case when an audio map for audio parts is added subsequently to a video map for video parts, in accordance with the still picture group information.

0060Before reproduction, a reproduction mode may be set through a user interface to determine whether only a still picture is to be reproduced, or both a still picture and audio data are to be reproduced.

0061As described above, a plurality of still pictures and audio data added thereto can be recorded and/or reproduced using minimum information by storing still picture group information for separating the plurality of still pictures and audio data into within a predetermined maximum number of groups in order to manage the still pictures at a group level.

0062Also, since the still picture group information includes still picture group general information as the common information of in the recording order of bitstreams of still pictures and audio data added thereto, and video part information and audio part information are constructed for each still picture in the still picture group, effective management of information can be performed.

0063The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

0064All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

0065Each feature disclosed in this specification (including any accompanying claims, abstract and drawings), may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

0066The invention is not restricted to the details of the foregoing embodiment(s). The invention extend to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.