Patent Publication Number: US-2005117885-A1

Title: DVD player and method of reproducing multimedia file using the DVD player

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
      This application is related to Korean Patent Application No. 2003-002960, filed on Jan. 16, 2003 and laid open Jul. 23, 2004, in the Korean Intellectual Property Office.  
     BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to a digital versatile disc (DVD) player. More particularly, the present invention relates to a DVD player and a method of reproducing multimedia files using a DVD player that can improve the practical applicability and usefulness of a common DVD player by enabling reproduction of multimedia information stored in various multimedia formats (such as, moving picture experts group (MPEG)-4, digital video express (DivX)) even in a typical DVD player via codecs. Codecs that correspond to various multimedia formats are downloaded via a memory stick or other external port so that not only moving picture multimedia information stored in MPEG-2 format, which is the basic DVD format, but also the multimedia information recorded in various other multimedia formats such as MEPG-4 and DivX can be reproduced.  
      2. Description of the Related Art  
      Generally, a DVD is an optical disc with a diameter of about 12 cm on which about 135 minutes of audio and video data (that is, multimedia information) that can be reproduced are digitalized and recorded. The DVD can record multimedia information such as a movie with image quality similar to television broadcasting on a disk having the same diameter as a compact disc (CD). The recording capacity of a DVD is six to eight times greater than the recording capacity of a typical CD. The recording capacity can be increased by, for example, increasing the numerical aperture of an objective lens that focuses a red semiconductor laser, whose wavelength (635-650 nm) is shorter than that of an infrared semiconductor laser (about 780 mm), used as a light source for CDs. Multimedia data (information) recorded (stored) on DVDs is condensed in an MPEG-2 format, which is an international standard format.  
      DVDs are usually used as a moving picture recording storage medium that can store moving picture multimedia information such as high quality movies. However, DVDs can also be used as DVD-ROMs, which represent the next generation version of CD-ROM, a read-only computer memory device. Therefore, software, personal computer (PC), and game device manufacturing industries are focusing a great deal of attention on DVDs.  
      As demand for access to multimedia information including moving pictures through the Internet increases, various multimedia (hereinafter, “multimedia” includes “moving picture”) formats such as MPEG-4 and DivX are being used. Along with the varied multimedia formats, codecs that correspond to the various multimedia formats also vary. For example, multimedia contents in DivX format are now more widespread than DVD titles on the Internet. Moreover, moving picture multimedia files in other types of formats are provided as well. For reference, codec is an abbreviation for “coder/decoder” or “compression/decompression.” A codec utilizes a compression algorithm for minimizing the memory storage space required for large or complex files such as video files. Decompression restores the compressed file to its original or substantially its original form. There are several standard methods for compressing and decompressing files used by codecs. Some of these methods are usually applied to the Internet in order to reduce file transmission time, while others are aimed at recording (storing) as much data as possible on a disc with a limited capacity such as a CD-ROM. Codecs are used in DVD players as well as numerous Internet products, for example, QuickTime, Netmeeting, Cu-SeeMe, and VDOphone.  
      In the conventional art, a codec appropriate for each multimedia format is needed to reproduce multimedia information in various formats. However, only a codec appropriate for the MPEG-2 format is installed in the conventional DVD player. Therefore, the conventional DVD player cannot reproduce moving picture multimedia information recorded in formats other than MPEG-2.  
     SUMMARY OF THE INVENTION  
      The present invention provides a digital versatile disc (DVD) player and a method of reproducing multimedia files using the DVD player that can improve the practical applicability and usefulness of a conventional DVD player by enabling reproduction of multimedia information stored in various multimedia formats (such as, moving picture experts group (MPEG)-4, digital video express (DivX)) even in a typical DVD player via codecs. Codecs that correspond to various multimedia formats are downloaded via a memory stick or other external port so that not only moving picture multimedia information stored in MPEG-2 format, which is the basic DVD format, but also multimedia information recorded in various other multimedia formats such as MEPG-4 and DivX can be reproduced.  
      According to an aspect of the present invention, there is provided a DVD player, comprising a loader that reads multimedia file data stored on a DVD; a memory that stores the multimedia file data read by the loader, and multimedia file data of a personal computer (PC) or multimedia file data downloaded from the Internet; and a controller that controls the loader and the memory. The controller comprises a file system module that controls the reading of the multimedia file data by the loader and controls the read multimedia file data by extracting a portion of or the entire multimedia file from the multimedia file data; a codec module that decodes the multimedia file using a codec driver that corresponds to the file extension of the multimedia file stored in the memory; and a user interface module that outputs video and or audio data of the decoded multimedia file to a video and or audio output device. The codec module includes a plurality of codec drivers to decode multimedia files in a plurality of formats and the memory is preferably composed of a memory stick or a CD-R.  
      The file system module may comprise a recording format recognizer that recognizes a recording format of the multimedia file data stored in the memory; a memory manager that manages the memory; a loader controller that controls a loading location of the multimedia file data; and a decoding controller that controls a first decoding of the multimedia file data read by the loader.  
      The codec module preferably includes at least an MPEG-2 codec driver, an MPEG-4 codec driver, and a DivX codec driver according to the file extension of the multimedia file stored in the memory, and other codec drivers that decode a plurality of multimedia files can be added in the codec module through software upgrades.  
      The user interface module preferably includes a key input unit that receives signals input by a user; a display controller that controls output of video data of the multimedia file decoded in the codec module; an audio input and or output controller that controls the output of the audio data of the multimedia file decoded in the codec module; and a reproduction mode controller that outputs a control signal that controls the reproduction mode of the multimedia file to the file system module.  
      The loader preferably includes an optical pickup that reads multimedia file data stored in the DVD; a radio frequency amplifier that converts the multimedia file data read by the optical pickup into high-frequency signals; and a digital signal processor that converts the high-frequency signals into digital signals.  
      According to another aspect of the present invention, there is provided a method of reproducing multimedia files using a DVD player. The method includes reading a multimedia file stored on a DVD and performing a first decoding; storing the multimedia file that went through the first decoding, and storing a multimedia file of a PC or a multimedia file downloaded from the Internet; performing a second decoding by a codec driver that corresponds to a file extension of the stored multimedia file; and outputting video and or audio data of the multimedia file that went through the second decoding to a video and or audio output device. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The above and other features and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which:  
       FIG. 1  is a schematic diagram of a digital versatile disc (DVD) player according to an embodiment of the present invention;  
       FIG. 2  is a detailed structural diagram of a loader of the DVD player illustrated in  FIG. 1  according to an embodiment of the present invention;  
       FIG. 3  is a detailed structural diagram of a file system module of the DVD player illustrated in  FIG. 1  according to an embodiment of the present invention;  
       FIG. 4  is a detailed structural diagram of a codec module of the DVD player illustrated in  FIG. 1  according to an embodiment of the present invention;  
       FIG. 5  is a detailed structural diagram of a user interface module of the DVD player illustrated in  FIG. 1  according to an embodiment of the present invention;  
       FIG. 6  is a flowchart illustrating a method of reproducing a multimedia file according to an embodiment of the present invention;  
       FIG. 7  is a flowchart illustrating a first decoding step of a method of reproducing a multimedia file according to an embodiment of the present invention; and  
       FIG. 8  is a flowchart illustrating a second decoding step of a method of reproducing a multimedia file according to an embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS  
      A digital versatile disc (DVD) player and a method of reproducing multimedia files using the same will now be described more fully with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. Descriptions of techniques or structures not central to the present invention have been omitted for the sake of clarity. In addition, the terminology that follows is defined according to the functions of the devices in the embodiments of the present invention and may change according to, for example, conventional usage or the intentions of a user or operator. Therefore, definitions should be derived based on the overall contents of the present application.  
       FIG. 1  is a schematic diagram of a DVD player according to an embodiment of the present invention.  FIGS. 2 through 5  are detailed structural diagrams of a loader  200 , a file system module  211 , a codec module  212 , and a user interface module  213 , respectively.  
      Referring to  FIG. 1 , the DVD player includes the loader  200 , a controller  210 , a memory  220 , an audio-to-digital (A/D) converter  230 , a digital-to-audio (D/A) converter  240 , a keypad  250 , a display unit  260 , a microphone  270 , and a speaker  280 . The memory  220  includes a storage medium (such as, a memory stick, a CD-R or other suitable memory device). The memory  220  reads multimedia files via the reader  210  and also stores multimedia files input through a personal computer (PC)  101  or downloaded from the Internet  103 .  
      The loader  200  reads data stored in a DVD  300  and outputs the data to the controller  210 . The loader  200 , as illustrated in  FIG. 2 , comprises an optical pickup  302 , a radio frequency (RF) amplifier  304 , a digital signal processor  306 , a DVD decoder  308 , and a motor driver  310 .  
      The controller  210  stores the data input from the loader  200  in the memory  220  or outputs the data through the speaker  280  via the D/A converter  240  or the display unit  260 . The controller  210  is configured as software so that it can perform multi-tasking. In this embodiment, if the software for multi-tasking is categorized according to its types of operations, the controller  210  includes the file system module  211 , the codec module  212 , the user interface module  213 , an audio post-processing module  214 , and a game engine module  215 . The file system module  211  extracts multimedia files from the data read from the DVD  300 , or from the PC  101 , or downloaded from the Internet  103 , and manages the multimedia files. The file system module  211  includes a recording format recognizer  402 , a memory controller  404 , and a loader controller  406 , as illustrated in  FIG. 3 .  
      The codec module  212  decodes the multimedia files extracted at the file system module  211 , and restores the multimedia files into video and audio data. Here, the codec module  212  includes a plurality of codec drivers to decode multimedia files in various formats extracted at the file system module  211 . That is, the codec module  212 , as illustrated in  FIG. 4 , includes at least an MPEG-2 codec driver  500 , an MPEG-4 codec driver  502 , and a DivX codec driver  504 , to decode the multimedia files read at the file system module  211  and output the multimedia files to the user interface module  213 .  
      The user interface module  213  reads the multimedia files from the file system module  211  according to a selection signal input via the keypad  250 , and outputs the data decoded at the codec module  212  to the display unit  260  or the D/A converter  240 . In this embodiment, the user interface module  213  includes a key input unit  600  to receive the selection signals and or key signals input from the keypad  250 , a display controller  260  to control the display unit  260 , an audio input/output controller  604  to control the A/D converter  230  and the D/A converter  240 , and a reproduction mode controller  606  to control a reproduction mode of multimedia files, as illustrated in  FIG. 5 . The audio post-processing module  214 , shown in  FIG. 2 , is configured to add various types of sound effects to audio signals decoded at the codec module  212 . The game engine module  215  is configured to operate games according to game data read from a DVD  300 .  
      The keypad  250  includes a plurality of function keys (such as, a power key, a reproduction mode selection key, and a sound effect operation key) to generate operation signals of a multimedia file player. The DVD player according to the present invention may further include a program memory (not shown) to store predetermined programs needed in initializing the controller  210 . In addition, the DVD player can be configured as a portable device.  
      In the operation of the DVD player, the optical pickup  302  of the loader  200  reads multimedia file data in various formats stored in the DVD  300 . Also, multimedia file data of the PC  101  and multimedia file data on the Internet  103  may be downloaded and stored in the memory  220 . Here, the controller  210  recognizes the data recording format of the DVD  300  using the recording format recognizer  402  of the file system module  211  and controls the DVD player so that the multimedia file data can be read via the optical pickup  302 . In addition, the controller  210  recognizes a recording format of the multimedia file data stored in the memory  220  via the recording format recognizer  402  of the file system module  211 . The memory  220  for storing multimedia files may include a memory stick or CD-R, as described above.  
      As is widely known, the RF amplifier  304  in  FIG. 2  converts the read multimedia file data into high-frequency signals (RF signals) via the optical pickup  302 , and outputs the high-frequency signals. The digital signal processor  306  converts the high-frequency signals into digital signals and outputs the digital signals to the DVD decoder  308 . The DVD decoder  308  corrects errors in the digital signals, descrambles the corrected data, and outputs the resulting data to the controller  210 . Here, the DVD decoder  308  is controlled by the loader controller  406  of the file system module  211  within the controller  210 , and the multimedia file data recorded on the DVD  300  is encoded or scrambled.  
      The motor driver  310  that is controlled by the load controller  406  of the file system module alters the rotation speed of the DVD  300  and the data reading location of the optical pickup  302 .  
      The memory controller  404  of the file system module  211  controls the storing of the processed multimedia files input from the loader  200  in the memory  220 , and manages the multimedia files of the PC  101  and the multimedia files downloaded from the Internet  103 .  
      The key input unit  600  of the user interface module  213  in  FIGS. 1 and 5  receives a multimedia file reproduction signal input via the keypad  250 , and outputs the multimedia file reproduction signal to the memory controller  404 . The memory controller  404  outputs a multimedia file that corresponds to the multimedia reproduction signal among the multimedia files stored in the memory  220  to the codec module  212 . The codec module  212  operates one of the MPEG-2 codec driver  500 , the MPEG-4 codec driver  502 , and the DivX codec driver  504  that corresponds to a file extension of the multimedia file. For example, the MPEG-2 codec driver  500  is operated when a multimedia (moving picture) file has the file extension “*.mpg”, the MPEG-4 codec driver  502  is operated when a multimedia (moving picture) file has the file extension “*.asf”, and the DivX codec driver  504  is operated when a multimedia (moving picture) file has the file extension “*.avi”. The codec module  212  decodes multimedia files by operating the MPEG-2 codec driver  500 , the MPEG-4 codec driver  502 , and the DivX codec driver  504 , corresponding to each type of multimedia file, restores the multimedia files into video and audio data, and outputs the video and audio data to the user interface module  213 . The display controller  602  of the user interface module  213  controls the output of the video data input from the codec module  212  via the display unit  206 . In addition, the audio input/output controller  604  of the user interface module  213  outputs the audio data, which is input from the codec module  212 , to the D/A converter  240 . The D/A converter  240  converts the audio data into analog audio data, and outputs the analog audio data via the speaker  280 .  
      Meanwhile, the audio input/output controller  604  encodes an audio signal via the codec module  212 , and stores the audio signal in the memory  220 . The audio signal is input via the microphone  270  and converted into digital data by the AID converter  230 . Audio signals stored in the memory  220  are output to the speaker  280  through the audio signal reproducing operation described above. When the video and or audio data input from the codec module  212  are output to the display unit  260  and or speaker  280 , the reproduction mode controller  606  of the user interface module  213  outputs control signals to manage the reproduction mode. Here, the reproduction mode includes numerous modes such as replay, fast forward, and rewind. That is, when the video and or audio data is output via the display unit  260  and the speaker  280 , the reproduction mode controller  606  outputs control signals for replaying, fast forwarding, and rewinding or reversing the video and or audio data, which is reproduced according to key input signals via the key input unit  600 , output from the display unit  260  and or the speaker  280 .  
      The audio post-processing module  214  outputs control signals for volume control, base and treble control, and 3D effect, according to the sound effect operation signals input via the key input unit  600 , and controls the sound effects of the audio signals output through the speaker  280 .  
      The game engine module  215  decodes the game data stored on the DVD  300  by successive operations of the file system module  211  and the codec module  212 , and performs the game using the decoded game data.  
      The reproduction of multimedia files using the DVD player according to an embodiment of the present invention described above will now be explained in more detail. First, a reproduction signal of a multimedia file of the DVD  300 , the PC  101 , or downloaded from the Internet  103 , is input. Then, the key input unit  600  of the user interface module  213  receives a multimedia file reproduction signal from the keypad  250 . The controller  210  selectively reads a multimedia file that corresponds to the reproduction signal input from the DVD  300  or the memory  220  via the key input unit  600 , via the loader  200 .  
      The controller  210  decodes a multimedia file stored in the memory  220  via one of the MPEG-2 codec driver  500 , the MPEG-4 codec driver  502 , and the DivX codec driver  504  of the codec module  212  that corresponds to the multimedia file. Then, the multimedia file is divided into video and audio data. The MPEG-2 codec driver  500 , the MPEG-4 codec driver  502 , or the DivX codec driver  504  of the codec module  212  that corresponds to the multimedia file outputs the video data to the display unit  260  through the control of the display controller  210  of the user interface module  213 . In addition, the corresponding codec driver outputs the audio data, which is decoded and divided, to the D/A converter  240  through the control of the audio input/output controller  604 . The D/A converter  240  converts the audio data into an analog signal and outputs it to the speaker  280 . Here, the audio post-processing module  214  outputs sound effect control signals (such as, a volume control signal, a base and treble control signal, and a 3D effect signal) to the D/A converter  240  according to the sound effect operation signal input via the keypad  250  by a user. The D/A converter  240  outputs the audio signal, whose sound effects are controlled in various ways according to the sound effect control signal, to the speaker  280 .  
      A method of reproducing multimedia files using the DVD player according to the embodiment of the present invention described above will now be described.  
       FIG. 6  is a flowchart illustrating a method of reproducing a multimedia file according to an embodiment of the present invention. First, multimedia file data recorded on the DVD  300 , a multimedia file of the PC  101 , or a multimedia file downloaded from the Internet  103  is read (S 700 ). Next, the read multimedia file data is subject to descrambling and error correction (S 702 ). Then, a first decoding is performed on the resulting multimedia file data and the resulting multimedia file data is stored in the memory  220  (S 704 ). In operation S 704 , the controller  210  recognizes a recording format of the read multimedia file via the recording format recognizer  402 . Also, in the case of the DVD  300 , after the multimedia file data is read according to its recognized recording format and converted into a high-frequency signal, the controller  210  decodes the multimedia file data converted into the high-frequency signal to correct errors in the multimedia file data and to descramble the multimedia file data. Here, the overall operation of the loader  200  is controlled by the controller  210 . Next, the controller  210  performs a second decoding via one of the MPEG-2 codec driver  500 , the MPEG-4 codec driver  502 , and the DivX codec driver  504  that corresponds to the file extension of the multimedia file stored in the memory  220  (S 706 ). Here, the second decoding decodes the multimedia file and outputs video and audio data.  
      The controller  210  outputs video and or audio data of the multimedia file that went through second decoding to the display unit  260  and speaker  280  via the D/A converter  240 .  
      The first decoding process in the method of reproducing the multimedia file according to an embodiment of the present invention will now be described in more detail with reference to  FIG. 7 , which is a flowchart illustrating an exemplary first decoding process. First, multimedia file data recorded on the DVD  300 , a multimedia file of the PC  101 , or a multimedia file downloaded from the Internet  103  is decoded (S 800 ). The controller  210  checks whether any errors are included within the read multimedia file data (s 802 ). If errors are detected in the read multimedia file in S 800 , the DVD  300  corrects the errors (S 804 ) and performs descrambling to decode the encoded multimedia file data (S 806 ).  
      An exemplary second decoding process in the method of reproducing the multimedia file according to an embodiment of the present invention will now be described in more detail with reference to  FIG. 8 , which is a flowchart illustrating the second decoding process. First, the controller  210  determines the file extension of the multimedia file stored in the memory  220  (S 900 ), and selects one of the MPEG-2 codec driver  500 , the MPEG-4 codec driver  502 , and the DivX codec driver  504  that corresponds to the determined file extension (S 902 ). That is, the controller  210  selects the MPEG-2 codec driver  500  when the multimedia file has the file extension “*.mpg”, selects the MPEG-4 codec driver  502  when the multimedia file has the file extension “*.asf”, and selects the DivX codec driver  504  when the multimedia file has the file extension “*.avi”. Afterwards, the controller  210  decodes the multimedia file via the selected codec driver, and outputs video and audio data (S 904 ).  
      According to a DVD player and a method of reproducing multimedia files using the same, embodiments of the present invention can improve the practical applicability and the usefulness of a common DVD player by enabling reproduction of multimedia information stored in various multimedia formats (e.g., MPEG-4, DivX) via codecs. Codecs that correspond to each of the multimedia format are downloaded via a memory stick or other external port so that not only moving picture multimedia information stored in MPEG-2 format, which is the basic DVD format, but also multimedia information recorded in various other multimedia formats such as MEPG-4 and DivX, can be reproduced.  
      While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims.