Abstract:
Disclosed is a mobile communication terminal and a method for reproducing digital broadcasting by a mobile communication terminal equipped with a moving picture player, the method including receiving digital broadcasting data, detecting CODEC information necessary for reproduction of the digital broadcasting, while parsing the received digital broadcasting data into video and audio data, setting the detected CODEC information in the moving picture player, and reproducing the video and audio data by the moving picture player in which the CODEC information has been set. The mobile communication terminal can reproduce digital broadcasting without a separate multimedia chip, thereby reducing the power consumption of the terminal.

Description:
PRIORITY  
       [0001]     This application claims the benefit under 35 U.S.C. §119 of applications filed in the Korean Industrial Property Office on Aug. 25, 2005 and assigned Serial No. 2005-78361, and filed on Aug. 18, 2006 and assigned Serial No. 2006-78330, the contents of each of which are incorporated herein by reference.  
       BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates generally to digital broadcasting, and more particularly to a mobile communication terminal and a method for reproducing digital broadcasting by using a moving picture player.  
         [0004]     2. Description of the Related Art  
         [0005]     In general, digital broadcasting refers to a high class broadcasting service that provides a higher quality screen and sound over that of the conventional analog broadcasting.  
         [0006]     With the recent development in digital broadcasting and mobile communication technologies, extensive research is being conducted on providing a digital broadcasting service which allows users to view digital broadcasting even when in motion. Particular research is being conducted on the Digital Multimedia Broadcasting (DMB) service using mobile communication terminals. DMB refers to a broadcasting service which allows a user to view various multimedia broadcasts through multiple channels even when in motion by using a personal portable receiver or an automobile-installed receiver equipped with a non-directional antenna.  
         [0007]      FIG. 1  is a view illustrating a conventional system for providing a digital broadcasting service.  
         [0008]     Referring to  FIG. 1 , the system includes a data transmission center  10 , a satellite  20  and receivers including, for example, a mobile communication terminal  30 , an automobile receiver  40  and a home receiver  50 .  
         [0009]     The data transmission center  10  compresses and modulates digital multimedia broadcasting data such as image, voice and data signals, and then transmits the modulated data to the satellite  20 .  
         [0010]     The satellite  20  receives, amplifies and frequency-converts the signals transmitted from the data transmission center  10 , and then transmits the signals back to the ground.  
         [0011]     The receivers  30 ,  40  and  50  receive the signals transmitted back from the satellite  20 , demodulate and de-compress the received signals into original signals, and then output the restored original signals.  
         [0012]     Due to the rapid development in digital broadcasting service technology as described above, users can now view clear digital broadcasting without noise even while within a vehicle moving at a high rate of speed.  
         [0013]     Meanwhile, in order to implement the digital broadcasting receiving function, conventional mobile communication terminals require a separate multimedia chip in addition to a communication modem chip, such as a mobile station modem (MSM), to control the mobile communication function. In a mobile communication terminal equipped with the multimedia chip, the communication modem chip performs the mobile communication function in the manner of a telephone, and the multimedia chip performs the digital broadcasting receiving function.  
         [0014]     However, use of the multimedia chip increases power consumption, and the addition of the multimedia chip within a mobile communication terminal creates a limit in the design of the mobile communication terminal.  
       SUMMARY OF THE INVENTION  
       [0015]     Accordingly, the present invention has been made to solve the above-mentioned problems occurring in the prior art, and an object of the present invention is to provide a mobile communication terminal and a method for reproducing digital broadcasting without a multimedia chip.  
         [0016]     It is another object of the present invention to provide a mobile communication terminal and a method for reproducing digital broadcasting by using a moving picture player.  
         [0017]     In order to accomplish these objects, there is provided a first embodiment of a method for reproducing digital broadcasting by a mobile communication terminal equipped with a moving picture player, the method including receiving digital broadcasting data, detecting coder/decoder (CODEC) information necessary for reproduction of the digital broadcasting, while parsing the received digital broadcasting data into video and audio data, setting the detected CODEC information in the moving picture player, and reproducing the video and the audio data by the moving picture player in which the CODEC information has been set.  
         [0018]     In accordance with the present invention, there is provided a second embodiment of a method for reproducing digital broadcasting by a mobile communication terminal equipped with a moving picture player, the method including receiving digital broadcasting data in response to a request for reproduction of the digital broadcasting, detecting CODEC information necessary for reproduction of the digital broadcasting, while parsing the received digital broadcasting data into video and audio data, converting the detected CODEC information into session description protocol (SDP) formatted information and setting the converted information in the moving picture player, and reproducing the parsed video and audio data by the moving picture player in which the CODEC information has been set.  
         [0019]     In accordance with the present invention, there is provided a first embodiment of a mobile communication terminal equipped with a moving picture player, the mobile communication terminal including a digital broadcasting receiver for receiving digital broadcasting data, a demodulator for demodulating the received digital broadcasting data, a control unit which detects CODEC information necessary for reproduction of the digital broadcasting, while parsing the demodulated digital broadcasting data into video and audio data, sets the detected CODEC information in the moving picture player, and controls the moving picture player to reproduce the video, and the audio data.  
         [0020]     In accordance with the present invention, there is provided a second embodiment of a mobile communication terminal equipped with a moving picture player, the mobile communication terminal including a digital broadcasting receiver for receiving digital broadcasting data, a demodulator for demodulating the received digital broadcasting data, a control unit which detects CODEC information necessary for reproduction of the digital broadcasting while parsing the demodulated digital broadcasting data into video and audio data, converts the CODEC information into Session Description Protocol (SDP) formatted information, sets the converted information in the moving picture player, and controls the moving picture player to reproduce the video and the audio data, and a Real-Time Protocol (RTP) parser for transmitting the video and the audio data to the moving picture player according to a real-time protocol scheme. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0021]     The above and other objects, features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:  
         [0022]      FIG. 1  is a view illustrating a conventional system for providing a digital broadcasting service;  
         [0023]      FIG. 2  is a block diagram of a mobile communication terminal according to a first embodiment of the present invention;  
         [0024]      FIG. 3  is a flowchart for illustrating an operation process of the mobile communication terminal according to the first embodiment of the present invention;  
         [0025]      FIG. 4  is a block diagram of a mobile communication terminal according to a second embodiment of the present invention; and  
         [0026]      FIG. 5  is a flowchart for illustrating an operation process of the mobile communication terminal according to the second embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0027]     Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, a detailed description of known functions and configurations incorporated herein will be omitted for the sake of clarity and conciseness.  
         [0028]      FIG. 2  is a block diagram of a mobile communication terminal according to a first embodiment of the present invention. The following description is based on the mobile communication terminal being equipped with a communication modem chip.  
         [0029]     The mobile communication terminal according to the first embodiment includes a digital broadcasting receiver  110 , a demodulator  120 , a key input unit  130 , a control unit  140 , a memory  150 , a speaker  160  and a display unit  170 .  
         [0030]     The digital broadcasting receiver  110  receives digital broadcasting data and outputs the received data to the demodulator  120 . The digital broadcasting data is received in transport stream (TS) packets. In digital broadcasting, one broadcasting program includes multiple element streams (ESs) on the same temporal basis. That is, streams in the form of H.264 for image signals, advanced audio coding (AAC+) for voice signals, and for transmission of additional data are transmitted according to a time division scheme. Herein, H.264 is identical to MPEG 4 advanced video coding (AVC), and AAC+ is an audio codec.  
         [0031]     The TS includes 188 bytes of consecutive packets and four bytes of packet header. The structure of the TS packet is well-known in the art, so a description thereof is omitted here.  
         [0032]     The demodulator  120  demodulates the digital broadcasting data received by the digital broadcasting receiver  110  into a digital data stream and then outputs the demodulated digital data stream to the control unit  140 .  
         [0033]     The key input unit  130  may include character keys, number keys and various function keys, and outputs a key input signal corresponding to the key input by the user to the control unit  140 .  
         [0034]     The control unit  140  controls the general operation of the mobile communication terminal according to the first embodiment of the present invention. The control unit  140  may include a TS parser  141  and a moving picture player  145 . The TS parser  141  parses the digital broadcasting data in TS packets into video and audio data. The moving picture player  145  can provide a streaming service, such as a video on-demand (VOD) player. The moving picture player  145  includes an audio player  143  for decoding and outputting the audio data and a video player  144  for decoding and outputting the video data. Although not shown, the moving picture player  145  further includes a decoder for decoding the video and audio data.  
         [0035]     The control unit  140  controls the TS parser  141  to parse the demodulated digital broadcasting data into video and audio data, while detecting CODEC information necessary for reproduction of the digital broadcasting data. When H.264 contents are used in the digital satellite broadcasting, the sequence parameter set (SPS) and picture parameter set (PPS) information located after the network adaptation layer (NAL) header of the H.264 ES is used as CODEC information. The PPS corresponds to information about a picture that includes multiple consecutive slices, and the SPS corresponds to information about a sequence that includes several consecutive pictures. Further, when AAC+ contents are transmitted, an audio data transport stream (ADTS) header of an ADTS, which uses an audio data format, is used as the CODEC information.  
         [0036]     The TS parser  141  extracts decoding time stamp (DTS) information for indicating the decoding time and presentation time stamp (PTS) information for indicating digital broadcasting reproduction time from the digital broadcasting data, and then parses the video and audio data, that is, ESs. The parsed video data may be stored in either the memory  150  or a separate storage area. Thereafter, under the control of the control unit  140 , the moving picture player  145  reads and reproduces the video and audio data frame by frame. The stored video data corresponds to frames including the NAL header, and the stored audio data corresponds to frames without the ADTS header.  
         [0037]     The control unit  140  sets the detected CODEC information in the moving picture player  145 . Specifically, the control unit  140  sets the H.246 video CODEC information including the SPS and PPS information in the video player  144 , and sets the AAC+ audio CODEC information including the ADTS information in the audio player  143 .  
         [0038]     After completing the CODEC information setup for the moving picture player  145 , the control unit  140  causes the moving picture player  145  to reproduce the parsed video and audio data. The reproduced video and audio data are output through the speaker  160  and the display unit  170 .  
         [0039]     The memory  150  stores various information necessary for controlling the operation of the mobile communication terminal according to the first embodiment of the present invention. Further, the memory  150  may store digital broadcasting data or digital broadcasting program guide data (EPG) received by the digital broadcasting receiver  110 .  
         [0040]     The display unit  170  preferably includes a liquid crystal display (LCD) which can sufficiently support the resolution necessary for reproduction of digital broadcasting. When the LCD includes a touch screen, the display unit  170  can serve as an input unit.  
         [0041]      FIG. 3  is a flowchart illustrating an operation process of the mobile communication terminal according to the first embodiment of the present invention, in which the digital broadcasting is reproduced by transferring the CODEC information and the digital broadcasting data directly to a decoder without using an SDP or an RTP, which are used in the VOD protocol.  
         [0042]     Referring to  FIGS. 2 and 3 , the control unit  140  determines whether there is a request from a user for reproduction of digital broadcasting (step S 110 ). The user can request reproduction of the digital broadcasting either through a reserved key input or a key input according to a menu.  
         [0043]     The control unit  140  receives digital broadcasting data in response to the request for reproduction of digital broadcasting (step S 120 ). The received digital broadcasting data is demodulated into a digital data stream by the demodulator  120 .  
         [0044]     The control unit  140  causes the TS parser  141  to parse the demodulated digital broadcasting data into video and audio data, while detecting CODEC information necessary for reproduction of the digital broadcasting data (step S 130 ). The parsed video and audio data become an ES instead of the TS.  
         [0045]     The control unit  140  detects the CODEC information by scanning a program map table (PMT) of the TS packet. Specifically, the control unit  140  scans the PMT and detects CODEC information in a descriptor named “DecoderSpecificinfo” within the PMT. The PMT is one of four tables constituting program specific information (PSI) data in a PSI area of the TS packet. The PMT reports the location of each stream for the service, and reports the location of a stream having a program clock reference (PCR) necessary for the service.  
         [0046]     When the CODEC information has been detected, the control unit  140  sets the detected CODEC information in the moving picture player  145  (step S 140 ).  
         [0047]     Then, the control unit  140  reproduces the parsed video and audio data through the moving picture player  145  (step S 150 ). The reproduced video and audio data are output through the speaker  160  and the display unit  170 .  
         [0048]      FIG. 4  is a block diagram of a mobile communication terminal according to a second embodiment of the present invention. The following description is based on the mobile communication terminal being equipped with a communication modem chip, and that the digital broadcasting is reproduced by using an SDP and an RTP.  
         [0049]     The mobile communication terminal according to the second embodiment includes a digital broadcasting receiver  210 , a demodulator  220 , a key input unit  230 , a control unit  240 , a memory  250 , a speaker  260  and a display unit  270 .  
         [0050]     The digital broadcasting receiver  210  receives digital broadcasting data and outputs the received data to the demodulator  220 .  
         [0051]     The demodulator  220  demodulates the digital broadcasting data received by the digital broadcasting receiver  210  into a digital data stream and then outputs the demodulated digital data stream to the control unit  240 .  
         [0052]     The key input unit  230  may include character keys, number keys and various function keys, and outputs a key input signal corresponding to the key input by the user to the control unit  240 .  
         [0053]     The control unit  240  controls the general operation of the mobile communication terminal according to the second embodiment of the present invention. The control unit  240  may include a TS parser  241 , an RTP parser  242  and a moving picture player  245 . The TS parser  241  parses the digital broadcasting data in TS packets into video and audio data. The RTP parser  242  transfers the parsed video and audio data according to an RTP scheme. The moving picture player  245  can provide a streaming service, and includes an audio player  243  and a video player  244 . Further, the moving picture player  245  reproduces an SDP and an RTP which are currently used in the VOD protocol.  
         [0054]     The control unit  240  causes the TS parser  241  to parse the demodulated digital broadcasting data into video and audio data, while detecting CODEC information necessary for reproduction of the digital broadcasting data. When H.264 contents are used in the digital satellite broadcasting, the SPS and PPS information located after the NAL header of the H.264 ES is used as the CODEC information. The PPS corresponds to information about a picture that includes multiple consecutive slices, and the SPS corresponds to information about a sequence that includes several consecutive pictures. Further, when AAC+ contents are transmitted, an ADTS header in an audio data format is used as the CODEC information.  
         [0055]     The TS parser  241  extracts decoding time stamp (DTS) information indicating the decoding time and presentation time stamp (PTS) information indicating digital broadcasting reproduction time from the digital broadcasting data, and then parses the video and the audio data, i.e., the ESs. The parsed video and audio data may be stored in either the memory  250  or a separate storage area. Thereafter, under the control of the control unit  240 , the moving picture player  245  reads and reproduces the video and audio data frame by frame. The stored video data corresponds to frames including the NAL header, and the stored audio data corresponds to frames without the ADTS header.  
         [0056]     The control unit  240  sets the detected CODEC information in the moving picture player  245  according to an SDP format. The CODEC information may be stored as an SDP file in the memory  250 .  
         [0057]     The memory  250  stores various information necessary for controlling the operation of the mobile communication terminal according to the second embodiment of the present invention. Specifically, the memory  250  stores CODEC information for reproduction of the digital broadcasting data in SDP files, so as to use the SDP currently used in the VOD protocol.  
         [0058]     Further, the memory  250  may store digital broadcasting data or digital broadcasting program guide data (EPG) received by the digital broadcasting receiver  210 .  
         [0059]     The display unit  270  preferably includes an LCD which can sufficiently support the resolution necessary for reproduction of the digital broadcasting. When the LCD includes a touch screen, the display unit  270  can serve as an input unit.  
         [0060]      FIG. 5  is a flowchart for illustrating an operation process of the mobile communication terminal according to the second embodiment of the present invention, in which the digital broadcasting is reproduced by using an SDP and an RTP which are currently used in the VOD protocol.  
         [0061]     Referring to  FIGS. 4 and 5 , the control unit  240  determines whether there is a request from a user for reproduction of digital broadcasting (step S 210 ).  
         [0062]     The control unit  240  receives digital broadcasting data in response to the request for reproduction of the digital broadcasting (step S 220 ). When the digital broadcasting data is stored in the memory  250 , the control unit  240  may read the stored digital broadcasting data.  
         [0063]     The control unit  240  causes the TS parser  241  to parse the demodulated digital broadcasting data into video and audio data, while detecting CODEC information (step S 230 ). The CODEC information includes video and audio CODEC information necessary for reproduction of the digital broadcasting data.  
         [0064]     The control unit  240  converts the detected CODEC information into SDP formatted information, and then sets the converted CODEC information in the moving picture player  245  (step S 240 ). At this time, the control unit  240  may store the CODEC information as an SDP file in the memory  250 . Then, the control unit  240  can immediately set the SDP file into the moving picture player  245  without a separate detection of the CODEC information when it reproduces the digital broadcasting.  
         [0065]     The control unit  240  causes the RTP parser  242  to transmit the parsed video and audio data to the moving picture player  245  (step S 250 ). The RTP parser  242  transfers the video and audio data to the moving picture player  245  according to an RTP scheme. That is, the RTP parser  242  transfers the video and audio data to the moving picture player  245  by using a protocol of the moving picture player  245  having a real-time streaming function. The RTP is well-known in the art, so a detailed description thereof will be omitted here.  
         [0066]     The control unit  240  controls the moving picture player  245 , in which the CODEC information has been set, to reproduce the video and audio data transferred to the RTP parser  242  (step S 260 ). The moving picture player  245  decodes the video and audio data based on the setup CODEC information, and then reproduces the decoded video and audio data through the speaker  260  and the display unit  270 .  
         [0067]     According to the present invention, a mobile communication terminal can reproduce digital broadcasting without a separate multimedia chip for reproduction of digital broadcasting. Therefore, the present invention can reduce the power consumption in a mobile communication terminal.  
         [0068]     Further, the present invention provides a mobile communication terminal which can reproduce digital broadcasting by using a moving picture player mounted therein. Therefore, it is unnecessary for a user to purchase a dedicated terminal for reproduction and viewing of digital broadcasting.  
         [0069]     While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.