HK1095004B - A method of recording video data in an information storage medium - Google Patents

Description

Method of recording video data in information storage medium

Technical Field

This application is a divisional application of a patent application having an application date of 27/2/2002, an application number of 02106401.6, entitled "method and apparatus for recording and reproducing video data".

Background

The video data and the hypertext data are multiplexed together in the digital broadcasting signal. The video data and the hypertext data are transmitted in the form of an MPEG Transport (TS) stream. The user receives and records the MPEG TS stream in the information storage medium, and can reproduce the MPEG TS stream when he/she wants to view it.

Fig. 17 is a diagram for explaining a problem of the related art. Referring to fig. 17, the video data (a) and the hypertext data (b) are respectively decoded and synthesized, thereby reproducing the MPEG TS stream as shown in synthesis (c). However, when the video data (a) in the MPEG TS stream is decoded and the video data (a ') re-encoded in other ways is recorded, the video data (a') and the hypertext data (b) cannot be properly synthesized and displayed during reproduction.

Disclosure of Invention

In order to solve the above-mentioned problems, it is an object of the present invention to provide a method and apparatus for correctly reproducing video data and hypertext data even if the video data has been re-encoded and recorded in a different manner, and an information storage medium therefor.

To achieve the above object of the present invention, in one embodiment, a method of recording video data in an information storage medium is provided. The method comprises the following steps: (a) decoding the video data; (b) encoding the decoded video data differently from the initial encoding; (c) generating video conversion information that is referred to when decoding video data into an initial state; and (d) recording the generated video transform information and the re-encoded video data.

In another embodiment, a method of recording video data in an information storage medium is provided. The method comprises the following steps: (a) separating video data from a bitstream containing the video data and hypertext data and decoding the video data; (b) encoding the decoded video data differently from the initial encoding; (c) generating video transform information that is referred to when the re-encoded video data is decoded to an initial state; (d) multiplexing the generated video conversion information, the re-encoded video data, and the hypertext data into a bitstream; and (e) recording the multiplexed bitstream in an information storage medium.

In still another embodiment, a method of recording video data in an information storage medium is provided. The method comprises the following steps: (a) separating video data from a bitstream in which the video data and the hypertext data are multiplexed and decoding the video data; (b) encoding the decoded video data differently from the initial encoding; (c) generating video conversion information that is referred to when decoding video data into an initial state; (d) recording the generated video conversion information in a navigation data area of the information storage medium; (e) multiplexing the re-encoded video data and hypertext data to be reproduced together with the video data into a bitstream; and (f) recording the multiplexed bitstream in a program area of the information storage medium.

To achieve the object of the present invention, there is also provided an information storage medium including video data that has been encoded in a different manner from an initial encoding manner, and video transform information that should be referred to when decoding the video data to an initial state.

Preferably, the information storage medium further includes audio data reproduced together with the video data, hypertext data displayed together with the video data, and program configuration data necessary for reproducing the video data.

Preferably, the video data, the audio data, and the video conversion information are multiplexed and recorded in the program area, or the video data, the audio data, and the hypertext data are multiplexed and recorded in the program area, and the video conversion information is recorded in the navigation data area as the program configuration data.

Preferably, the video data, the audio data, and the hypertext data are multiplexed and recorded in the program area in a format of a Moving Picture Experts Group (MPEG) transport stream, and the video transform information is recorded in the navigation data area as Program Map Table (PMT) configuration information.

Preferably, the video conversion information is embedded in the video element descriptor as a video conversion descriptor, and the video conversion descriptor includes a horizontal resolution, a vertical resolution, and an aspect ratio as variables.

An apparatus for receiving and recording a bitstream in an information storage medium is also provided. The device includes: a filter for extracting video data from an input bitstream; a recorder for decoding the extracted video data, re-encoding the decoded video data in a different manner from an original encoding manner, recording the encoded video data, and recording video transform information that is referred to when the video data is decoded to an original state; and a controller for generating and providing the video conversion information to the recorder.

Preferably, the recorder records the video transform information together with the re-encoded video data in the program area, or records the video transform information in the navigation data area.

The filter includes a demultiplexer for demultiplexing an input bitstream into video data, audio data, hypertext data, and program information data. The controller includes a video transition information generator for generating and outputting video transition information referred to when decoding video data into an initial state. The recorder includes: a video decoder for decoding the video data received from the demultiplexer; a video encoder for re-encoding the decoded video data; and a multiplexer for multiplexing the generated video transform information and the re-encoded video data.

Preferably, the controller includes: a filter for extracting a PMT packet from the program information data outputted from the demultiplexer; and a generator for generating PMT configuration information including video conversion information from the extracted PMT packet. The recorder records PMT configuration information in the navigation data area.

To achieve the object of the present invention, in one embodiment, there is provided a method of reproducing video data from an information storage medium in which video data encoded in a different encoding manner from an original encoding manner and video transform information that should be referred to when decoding the video data to an original state are recorded. The method comprises the following steps: (a) reading video data and hypertext data from the program area; (b) reading video conversion information from the navigation data area; and (c) multiplexing the video data, the hypertext data, and the video conversion information, and outputting the multiplexed result.

In another embodiment, there is provided a method of reproducing video data from an information storage medium in which video data encoded in a different encoding manner from an original encoding manner and video transform information that should be referred to when decoding the video data to an original state are recorded. The method comprises the following steps: (a) reading a bitstream to which video data, hypertext data, and video conversion information have been multiplexed from a program area; (b) demultiplexing the bitstream into video data, hypertext data, and video conversion information; (c) decoding the video data with reference to the video transform information; (d) decoding the hypertext data; and (e) mixing the decoded video data and the decoded hypertext data, and outputting a mixed result.

To achieve the object of the present invention, in one embodiment, there is provided an apparatus for reproducing video data from an information storage medium in which video data encoded in a different encoding manner from an original encoding manner and video transform information that should be referred to when decoding the video data to an original state are recorded. The device includes: a reader for reading the video data and the hypertext data recorded in the bit stream format from the program area and for reading program information data containing video conversion information from the navigation data area; a video conversion information extractor for extracting video conversion information from the program information data; and a remultiplexer for multiplexing the video data and the hypertext data supplied from the reader and the video conversion information supplied from the video conversion information extractor and outputting the multiplexed result.

The device also includes: a demultiplexer for demultiplexing the bitstream into video data and hypertext data; a video decoder for decoding the video data received from the demultiplexer with reference to the extracted video transform information; a hypertext data decoder for decoding the hypertext data received from the demultiplexer; and a mixer for mixing the decoded hypertext data and the decoded video data and outputting a result of the mixing.

Preferably, the reader reads an MPEG transport stream in which video data, audio data, and hypertext data are multiplexed. Preferably, the video transform information extractor generates a PMT packet containing the video transform information as PMT configuration information. Preferably, the remultiplexer multiplexes the MPEG transport stream and the PMT packet and outputs the multiplexed result.

In another embodiment, there is provided an apparatus for reproducing video data from an information storage medium in which video data encoded in a different encoding manner from an original encoding manner and video transform information that should be referred to when decoding the video data to an original state are recorded. The device includes: a reader for reading a transport stream in which video data, hypertext data, and video conversion information are multiplexed, from a program area; a demultiplexer for demultiplexing the read bitstream into video data, hypertext data, and video transform information; the analyzer is used for extracting video conversion information; a video decoder for decoding the video data received from the demultiplexer with reference to the extracted video transform information; a hypertext data decoder for decoding the hypertext data received from the demultiplexer; and a mixer for mixing the decoded hypertext data and the decoded video data and outputting a result of the mixing.

Drawings

The above objects and advantages of the present invention will become more apparent by the following detailed description of the preferred embodiments with reference to the attached drawings, in which:

fig. 1 is a block diagram of a recording apparatus according to a first embodiment of the present invention;

fig. 2 is a block diagram of a recording apparatus according to a second embodiment of the present invention;

fig. 3 and 4 are diagrams for explaining an MPEG Transport (TS) stream;

FIG. 5 is a data structure diagram in an information storage medium in which an MPEG TS stream is recorded by a recording apparatus of the present invention;

fig. 6A and 6B are diagrams of data structures of video transform information recorded according to an embodiment of the present invention;

FIG. 7 is a data structure diagram of navigation data according to an embodiment of the present invention;

fig. 8 is a data structure diagram of video transform information according to an embodiment of the present invention;

fig. 9 is a flowchart of a recording method according to the first embodiment of the present invention;

fig. 10 is a flowchart of a recording method according to a second embodiment of the present invention;

fig. 11 is a block diagram of a reproducing apparatus according to a first embodiment of the present invention;

fig. 12 is a block diagram of a reproducing apparatus according to a second embodiment of the present invention;

fig. 13 is a block diagram of a reproducing apparatus according to a third embodiment of the present invention;

fig. 14 is a flowchart of a reproducing method according to the first embodiment of the present invention;

fig. 15 is a flowchart of a reproducing method according to a second embodiment of the present invention;

fig. 16 is a flowchart of a reproducing method according to a third embodiment of the present invention; and

fig. 17 is a diagram for explaining a problem of the related art.

Detailed Description

Fig. 1 is a block diagram of a recording apparatus according to a first embodiment of the present invention. Referring to fig. 1, the recording apparatus includes a filter 1, a controller 2, and a recorder 3.

The filter 1 extracts video data from an input bitstream. The recorder 3 decodes the extracted video data, encodes the decoded video data in a different encoding manner from the original encoding manner, and records the encoded video data in an information storage medium, such as the disc 100. The controller 2 generates video transform information that is referred to when decoding video data into an initial state and transmits it to the recorder 3.

For example, when the bit stream is a digital broadcast stream transmitted from a digital television broadcasting station, the filter 1 filters packets containing program information data for reproduction and recording. In addition, the filter 1 filters the data packets of the selected program.

A digital broadcast stream is a sequence of data packets and information packets of a broadcast program. Packets are divided into two types. One is a first packet indicating an identifier of a packet in which a packet identifier of at least one broadcast program is recorded, and the other is a second packet indicating an identifier of a packet of a broadcast program. In other words, the identifier of the second packet is recorded in the first packet, and the identifier of the data packet of the broadcast program is recorded in the second packet. When multiple lanes are supported, there will be as many second packets as there are lanes. Each packet may physically comprise a plurality of packets.

In the case where the digital broadcast stream is an MPEG Transport (TS) stream, the packets containing program information data for reproduction and recording are a Program Association Table (PAT) packet and a Program Map Table (PMT) packet. The PAT packet is a first packet and the PMT packet is a second packet. The data packets are video packets, audio packets, and/or hypertext data packets.

Fig. 2 is the embodiment of fig. 1. Referring to fig. 2, a recording apparatus for receiving an MPEG TS stream and re-encoding it in a different manner from the original encoding includes a Demultiplexer (DEMUX)50, a video decoder 51, a video encoder 53, a filter 55, a Program Specific Information (PSI) generator 56, and a Multiplexer (MUX) 57. In addition, the recording apparatus may further include an audio decoder 52 and an audio encoder 54.

The DEMUX 50 receives and separates an MPEG TS stream into video data (and audio data), hypertext data, and program information data. More specifically, the MPEG TS stream is separated into a video Packet Element Stream (PES), an audio PES, hypertext data, and program information data, and is input to the video decoder 51, the audio decoder 52, and the filter 55, respectively. The video decoder 51 decodes the video PES, and the video encoder 53 encodes the decoded video PES in a different manner. Encoding in different ways includes compression methods, reduction or enlargement of data size, and so on. The audio decoder 52 decodes the audio PES, and the audio encoder 54 encodes the decoded audio PES in a different manner. When the audio decoder 52 and the audio encoder 54 are not configured, the audio PES is directly input to the MUX 57.

The filter 55 filters the hypertext data and the desired program information data. More specifically, the filter 55 filters a desired packet from PAT packets and PMT packets included in the MPEG TS stream, and periodically transmits the filtered packet. Program information data required for recording, reproducing, and searching for programs constituting the MPEG TS stream are recorded in the PAT packet and the PMT packet. The PSI generator 56 generates PSI that describes the program. The data structure of the PSI is defined in the MPEG system standard. Further, the PSI generator 56 extracts vertical and horizontal resolutions and an aspect ratio of video data from the output of the video decoder 51, embeds them into PMT packets as video conversion information, and transmits the generated PMT packets to the MUX 57. The vertical and horizontal resolutions and aspect ratios of video data are recorded in the header of the video data. The MUX 57 multiplexes the input video data, audio data, hypertext data, and PMT packets containing video conversion information, and outputs the multiplexed data stream. The multiplexed data stream is recorded in a program area of the disc 200.

Alternatively, instead of multiplexing the PMT packet with the video data, the audio data, and the hypertext data, the MUX 57 may transmit the PMT packet as it is so as to record only the PMT packet in the program information data area of the disc 200. The PMT packet may be recorded in a PMT format in which PMT configuration information is recorded.

Fig. 3 and 4 are diagrams for explaining an MPEG TS stream. Referring to fig. 3, video packets 31, 33, 34, and 37, and audio packets 32, 35, and 36 are multiplexed into an input MPEG TS stream 300. Upon receipt of the MPEG TS stream 300, the video packets 31, 33, 34, and 37 and the audio packets 32, 35, and 36 are separated and recombined into a video stream 302 and an audio stream 301.

Referring to fig. 4, each of MPEG TS packets 41, 42, 43, 44, 45, 46 and 47 constituting an MPEG TS stream 400 is assigned a packet identifier. Similarly, upon receipt of the MPEG TS stream 400, the packets are separated during decoding, and the packets having the same identifier are combined into one file. In other words, as shown in fig. 4, a group integrated flow 401 having a group identifier 1 and a group integrated flow 402 having a group identifier 2. The PAT packet is assigned a special packet identifier. In fig. 4, the packet having the packet identifier 0 is a PAT packet. The same number of PMT packet identifiers as the number of supported channels are recorded in the PAT packet. For simplicity, the PAT packet is represented as a single packet, but as described above, the PAT packet may include a plurality of packets.

Fig. 5 is a diagram illustrating an information storage medium in which an MPEG broadcast program is recorded by a recording apparatus according to the present invention. Referring to fig. 5, a data recording area of an information storage medium is divided into a navigation data area in which navigation data is recorded and a program area in which programs #1, # 2., # n are recorded. A program is composed of a bit stream in which video data (and audio data) and hypertext data are multiplexed. Each of the programs #1, #2, # n is one logical unit of content recorded in the information storage medium. The navigation data is information required for recording, reproducing, or editing a program and general information described in the program.

Fig. 6A and 6B are diagrams of data structures of video transform information recorded according to an embodiment of the present invention. Referring to fig. 6A, a PMT including PMT configuration information is recorded in the navigation data area. Referring to fig. 6B, the PMT containing PMT configuration information is embedded in a bitstream and recorded in a program data area.

Fig. 7 is a data structure diagram of navigation data according to an embodiment of the present invention. Referring to fig. 7, the navigation data includes a volume manager table. The volume manager table contains management information for a plurality of programs recorded in the information storage medium. The volume manager table includes volume general information VOL _ GL about the information storage medium, a program search pointer table PG _ SRPT indicating the location of program information, and a program information table PG _ IT # about each program.

The VOL _ GL contains the numbers PG _ Ns of all programs recorded in the information storage medium. PG _ SRPT indicates an offset value PG _ IT _ SRP # of the corresponding program information table to the start position of the volume manager table. There are as many offset values PG _ IT _ SRP # as the number of programs.

The program information table PG _ IT contains information necessary for reproducing a program. The fields constituting the program information table PG _ IT will be sequentially described below. The PAT _ SA is a start address of the PAT, and indicates an offset value of the PAT to the start position of PG _ IT. The PMT _ SA is a start address of the PMT, and indicates an offset value of the PMT to the start position of PG _ IT. TMAP _ SA is the start address of the Time Map (TMAP) and indicates the offset value of the start location of the associated PAT to PG _ IT. The PAT has the same structure as the program association table structure defined in the MPEG-2 standard. The PAT may be modified to have a structure in which PMT information recorded in a PMT packet is used only for a predetermined program reference at the time of recording. PMT configuration information contained in the PMT packet is recorded in the PMT. In addition, the video transform information according to the present invention is embedded in the PMT. TMAP is a table that maps time to location (address). The TMAP may have the same structure as that of a DVD-VR or DVD-Streamer (DVD-Streamer).

The video conversion information contains resolution and aspect ratio. The resolution indicates the resolution of the video data of the initial state contained in the bitstream. The aspect ratio indicates the aspect ratio of the pixel, and may indicate the aspect ratio of the display screen as needed.

Fig. 8 is a data structure diagram of video conversion information according to an embodiment of the present invention. Referring to fig. 8, video transform information is embedded in a PMT or PMT packet. The video element descriptors according to the MPEG specification are defined in PMT packets. The video element descriptor is used to record information indicating, for example, which of MPEG-1, MPEG-2, and MPEG-4 video data specifications is to be followed. A video transform descriptor, which is video transform information according to the present invention, is added in the video element descriptor. The video transform descriptor indicates a resolution and an aspect ratio of video data before re-encoding. The following is an example of a video conversion descriptor contained in a video element descriptor.

Here, "descriptor _ tag" represents an identifier of the video conversion descriptor, "descriptor _ length" represents a data size of the video conversion descriptor, "horizontal _ size" represents a horizontal resolution, "vertical _ size" represents a vertical resolution, and "aspect _ ratio _ information" represents an aspect ratio.

The PMT packet according to the MPEG specification is defined as follows.

[0062] Here, "stream _ type ═ 0x 02" indicates video data. In other words, when "stream _ type ═ 0x 02", the "descriptor ()" is a video element descriptor that describes video data. The video transform descriptor according to the present invention is embedded in the video element descriptor, as shown below.

A recording method according to the present invention will be described below based on the above-described structure.

Fig. 9 is a flowchart of a recording method according to a first embodiment of the present invention. Referring to fig. 9, the recording apparatus generates video conversion information for the received MPEG TS stream, embeds the video conversion information into the PMT as PMT configuration information, and records the PMT in a navigation data area separate from an area where a program is recorded, in step 901. Here, the recording device may record the PMT configuration information in a format in which a PMT packet replaces a PMT. Although the PMT occupies less recording space, PMT configuration information in the PMT must be rearranged into a PAT packet and a PMT packet before being transmitted to an MPEG decoder during reproduction. When recording the PAT packet and the PMT packet, rearrangement is no longer necessary, but the recording space for the PAT packet and the PMT packet increases. In step 902, the recording apparatus extracts MPEG TS packets of a program requested to be recorded by a user, encodes video data of the MPEG TS packets in a different encoding manner from the original encoding manner, and records the encoded video data in the program area. Whether to record the PAT packet and the PMT packet together with the recorded video data is optional. Both step 901 and step 902 may be performed before each other. Alternatively, steps 901 and 902 may be performed synchronously by a time-sharing method.

Fig. 10 is a flowchart of a recording method according to a second embodiment of the present invention. Referring to fig. 10, the recording apparatus receives an MPEG TS stream in which video data and hypertext data are multiplexed, and changes the resolution of the video data at the time of recording. In other words, the video decoder 51 decodes the video data in step 1001. The video encoder 53 re-encodes the decoded video data of which the resolution has been changed in step 1002. The filter 55 provides the hypertext data demultiplexed from the MPEG TS stream to the MUX 57 in step 1003. The PSI generator 56 generates and embeds video transform information (video transform descriptor) into the video element descriptor at step 1004. The MUX 57 multiplexes the encoded video data (and audio data) and hypertext data and outputs the multiplexed result in step 1005. The recording apparatus records PMT configuration information including video transform information (video transform descriptor) embedded in the video element descriptor in the navigation data area in step 1006, and records the multiplexed bitstream in the program area in step 1007.

Fig. 11 is a block diagram of a reproducing apparatus according to the present invention. Referring to fig. 11, the reproducing apparatus includes a decoder 5, a video conversion information extractor 6, and a reader 4. The reader 4 reads the bit stream data and the video conversion information from the disc 300. The video conversion information extractor 6 extracts video conversion information from the bitstream data read by the reader 4 and supplies it to the decoder 5. The decoder 5 decodes the bit stream data into an initial state with reference to the video conversion information.

Fig. 12 illustrates an embodiment of the reproducing apparatus of fig. 11. Referring to fig. 12, the reproducing apparatus includes a reader 4, a DEMUX 60, a video decoder 61, an audio decoder 62, a filter 65, a PSI parser 66, a hypertext data decoder 63, and a mixer 64. In this embodiment, the PSI parser 66 is configured as the video conversion information extractor 6.

The reader 4 reads a bitstream from a disc 500 serving as an information storage medium and outputs the bitstream. Video data (and audio data) and hypertext data are multiplexed in the bit stream. In particular, according to the present invention, the video transform information has been multiplexed into a bitstream in the form of PMT packets. The bit stream is output as a digital signal or input into the DEMUX 60. The DEMUX 60 demultiplexes the bitstream into video data, audio data, hypertext data, and program information data. The filter 65 filters out the hypertext data and the program information data so as to output only the necessary hypertext data and program information data. The PSI parser 66 parses the video conversion information from the program information data and transmits the video conversion information to the video decoder 61. The video decoder 61 decodes the video data according to the initial resolution and the aspect ratio (video conversion information) provided by the PSI parser 66, and provides the decoded video data to the mixer 64. The audio decoder 62 decodes the audio data and supplies the decoded audio data to the sound output device. The hypertext data decoder 63 decodes the hypertext data output from the filter 65 and supplies the decoded hypertext data to the mixer 64. The mixer 64 mixes the video data and the hypertext data and outputs the result of the mixing.

Fig. 13 shows another embodiment of fig. 11. Referring to fig. 13, the reproducing apparatus includes a reader 4, a video conversion information extractor 6, a REMUX67, a DEMUX 60, a video decoder 61, an audio decoder 62, a filter 65, a PSI parser 66, a hypertext data decoder 63, and a mixer 64. Specifically, in the present embodiment, the PSI parser 66 is included in the decoder 5, and the video conversion information extractor 6 is separately configured independently of the PSI parser 66. Further, unlike the reproduction apparatus of fig. 12, the decoder 5 further includes a REMUX 67.

The reader 4 reads a bitstream from a disc 400, which is an information storage medium, and outputs it to the video conversion information extractor 6 and/or the DEMUX 60. Video data (and audio data) and hypertext data are multiplexed in the bit stream. Further, the reader 4 reads video conversion information, which has been recorded as PMT configuration information, from the navigation data area and outputs it to the video conversion information extractor 6.

The video transform information extractor 6 extracts the video transform information and provides it to the REMUX67 and/or the video decoder 61. The REMUX67 multiplexes the bit stream and the video conversion information to output a digital signal. The DEMUX 60 demultiplexes the bitstream into video data, audio data, hypertext data, and program information data. The video decoder 61 decodes the video data according to the initial resolution and the aspect ratio (video conversion information) supplied from the video conversion information extractor 6, and supplies the decoded video data to the mixer 64. The audio decoder 62 decodes the audio data and supplies the decoded audio data to the sound output device. The hypertext data decoder 63 decodes the hypertext data output from the filter 65 and supplies the decoded hypertext data to the mixer 64. The mixer 64 mixes the video data and the hypertext data and outputs the result of the mixing. The program information data is processed by the filter 65 and parsed by the PSI parser 66.

A reproducing method according to the present invention will be described below based on the above-described structure.

Fig. 14 is a flowchart of a reproducing method according to the first embodiment of the present invention. Referring to fig. 14, the video transform information extractor 6 transmits PMT configuration information corresponding to a program to be reproduced to the decoder 5 in step 1401. The PMT configuration information contains video transform information. The reader 4 reads the bit stream of the program in step 1402 and sends it to the decoder 5 in step 1403. The decoder 5 multiplexes the bit stream and the video conversion information into a digital signal.

Fig. 15 is a flowchart of a reproducing method according to a second embodiment of the present invention. Referring to fig. 15, the reader 4 reads an MPEG TS stream in which video conversion information is multiplexed into PMT configuration information from the disc 500 and outputs the MPEG TS stream in step 1501. The reproducing apparatus reads and reproduces an MPEG TS stream containing video data recorded at the changed resolution. In other words, the DEMUX 60 demultiplexes the MPEG TS stream read from the disc 500 into video data, audio data, hypertext data, and program information data in step 1502. The filter 65 performs filtering in step 1503 to output the required hypertext data and program information data. The PSI parser 66 parses the video transition descriptor received from the filter 65 and provides the parsed video transition descriptor to the video decoder 61 at step 1504. The video decoder 61 decodes video data with reference to the video transform descriptor so that the video data has an original resolution in step 1505. The audio decoder 62 decodes the audio data at step 1506 and outputs the decoded audio data to a sound output device (speaker). The hypertext data decoder 63 decodes the hypertext data in step 1507. The mixer 64 mixes the decoded video data and the decoded hypertext data and outputs the mixed result to a display device (not shown) in step 1508. Accordingly, the video data and the hypertext data can be displayed in an initial state.

Fig. 16 is a flowchart of a reproducing method according to a third embodiment of the present invention. Referring to fig. 16, the reader 4 reads an MPEG TS stream from a program area of the disc 400 and outputs it to the REMUX67 and the DEMUX 60 in step 1601. At step 1602, the reader 4 reads PMT configuration information from the navigation data area of the disc 400, and the video conversion information extractor 6 generates a PMT packet according to the PMT configuration information and provides the PMT packet to the REMUX 67. The REMUX67 multiplexes the MPEG TS stream and PMT packet into a digital signal at step 1603. The DEMUX 60 demultiplexes the MPEG TS stream into video data, audio data, hypertext data, and program information data at step 1604. The filter 65 performs filtering in step 1605 to output the required hypertext data and program information data. The video transform information extractor 6 provides the video transform information (video transform descriptor) to the video decoder 61 at step 1606. The video decoder 61 decodes the video data with reference to the video conversion information (video conversion descriptor) so that the video data can have the original resolution in step 1607. The audio decoder 62 decodes the audio data and outputs the decoded audio data to a sound output device (speaker) at step 1608. The hypertext data decoder 63 decodes the hypertext data in step 1609. The mixer 64 mixes the decoded video data and the decoded hypertext data and outputs the mixed result to a display device (not shown) at step 1610. Accordingly, the video data and the hypertext data can be displayed in an initial state.

The above-described recording and reproducing methods may be embodied as computer programs. Codes and code segments constituting the program can be easily derived by computer programmers in the art. Further, the program is recorded on a computer-readable medium. The program is read and executed by a computer, thereby implementing a method of recording and reproducing an MPEG broadcast program. The computer readable medium may be a magnetic recording medium, an optical recording medium, or a carrier wave medium.

As described above, according to the present invention, even if video data has been re-encoded in a different manner from the original encoding manner, video data and hypertext data can be correctly reproduced.

Claims (2)

1. A method of recording video data in an information storage medium, the method comprising:

decoding the initially encoded video data;

encoding the decoded video data in a different manner than the original encoding;

generating video transform information including an initial resolution and an aspect ratio of the initially encoded video data;

multiplexing the generated video transform information and the re-encoded video data into a bitstream; and

the multiplexed bitstream is recorded in an information storage medium.

2. The method of claim 1, wherein the video transform information is included in a program map table packet.