KR20000046849A - Method for image pick up/play back of digital broadcasting receiver - Google Patents

Abstract

PURPOSE: A method for image pick up/play back of a digital broadcasting receiver is provided to display the information on the picked up image in a list and to display desired image based on user selection. CONSTITUTION: A method for image pick up/play back of a digital broadcasting receiver includes a first thru third steps. At the first step, whether an image pickup is required is determined. At the second step, whether a particular port of a MPEG(moving picture experts group) A/V decoder is at a predetermined level is determined when the image pickup is required. At the third step, a particular picture data at the particular port is stored in an auxiliary flash memory when the particular port of the MPEG A/V decoder is at the predetermined level.

Description

Image Acquisition / Playback Method of Digital Broadcast Receiver

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a broadcast receiver, and more particularly, to a method of acquiring / reproducing an image of a digital broadcast receiver, which enables acquisition, storage, and reproduction of a desired scene while watching a broadcast in a digital TV system.

Currently, digital TV broadcasting includes digital satellite broadcasting through satellites and terrestrial digital broadcasting using terrestrial waves, and cable digital broadcasting will also be implemented.

The transmission media (satellite, terrestrial, and cable) are significantly different in these three broadcasting methods, but the rest of the video and audio compression and packet composition are almost the same.

Therefore, the configuration of these broadcast receivers also differs only in the part related to the transmission method, and the rest are almost similar.

Currently, the basic transmission format of digital broadcasting is shown in FIG. 1 (d), which is an MPEG2 TS (Transport Stream) set as an international standard, and is defined in the ISO / IEC 13818-1 standard.

'TS' includes various additions such as a video packet (Video PES; Packetized Elenentary Stream) as shown in FIG. 1 (a), an audio packet (audio PES) as shown in FIG. 1 (b), and a program guide as shown in FIG. Program packets (PSI) are multiplexed, and each packet is composed of a header and an elementary system (ES), as shown in FIG.

At this time, the video ES is usually composed of data of a video picture layer.

Therefore, by properly collecting the picture layer data in the video ES, one picture can be constructed, and usually one picture is the same as one picture frame.

The one picture layer data is composed of a picture header and the remaining part (video data) as shown in FIG.

At this time, a form in which multiple packets of video, audio, and additional information are multiplexed with each other is transmitted by a digital broadcast transmitter as shown in FIG.

That is, in the digital broadcast transmitter, when the video compression unit 101 compresses the video signal and the audio compression unit 102 compresses the audio signal, the multiplexer 103 adds the video compression signal and the audio compression signal as additional information (PSI). Will be multiplexed with.

Accordingly, the modulator 104 modulates and outputs the output signal of the multiplexer 103.

Accordingly, the digital broadcast receiver tunes a desired channel to restore the original video / audio signal by receiving a broadcast signal, thereby allowing the viewer to listen to the audio corresponding to the video output through the speaker while watching the video displayed on the screen.

FIG. 5 is a block diagram showing a signal processing apparatus of a general digital broadcast receiver. As shown in FIG. 5, a tuner 211 tunes a desired channel from a broadcast signal received by an antenna and a tuner signal of the tuner 211. An analog / digital converter 212 for converting the signal into a form signal, a link unit 213 for demodulating the output signal of the analog / digital converter 212 to correct an error, and an output signal of the link unit 213. A microcomputer 222 that demultiplexes and separates the MPEG compressed video, audio streams and additional information into a database which is provided with information that can be provided to the viewer, and the microcomputer 222 sends user commands on the remote control or keypad; Interface unit 221 to be input to the flash memory, a flash memory 223 storing an execution program of the microcomputer 222, and the microcomputer 222 of the The DRAM 224 stores variables according to signal processing, and MPEG compressed video and audio streams input from the microcomputer 222 are temporarily stored in the SDRAM 231 to store original MPEG video / audio data. The NTSC encoder 233 for signal processing the MPEG A / V decoder 232 to be restored and the original MPEG video data output from the MPEG A / V decoder 232 to output NTSC signals (Y, C, CVBS). And a digital-to-analog converter 234 that outputs analog voice signals R and L by inputting signals SD, CLK and R / L from the MPEG A / V decoder 232.

The microcomputer 222 may control the tuning operation of the tuner 211 through the IIC bus and transmit graphic information indicating a result of the execution of the user command to the NTSC encoder 233.

Referring to the operation of the conventional device as follows.

When the broadcast signal is received by the antenna and the tuner 211 tunes to a specific broadcast channel under the control of the microcomputer 222, the analog / digital converter 212 converts the tuned signal into a digital signal and the link unit 213. ) Performs demodulation and error correction as the input of the digital signal.

The tuner 211 uses a tuner that fits the frequency spectrum of satellite, terrestrial, and cable broadcasts. The error correction scheme of the link unit 213 is generally similar in three broadcasts, and the demodulation scheme is determined according to each broadcast transmission medium. different.

At this time, the microcomputer 222 demultiplexes the output signal of the link unit 213 to separate the MPEG compressed video / audio stream and the additional information, and outputs the MPEG compressed video / audio stream to the MPEG A / V decoder 232. The additional information is databased into information that can be provided to the viewer through an analysis and combination process.

Accordingly, the MPEG A / V decoder 232 stores the MPEG multiplexed video / audio stream demultiplexed in the microcomputer 222 in the SDRAM 231 and decodes the MPEG video / audio data extended to the original signal. Will be restored.

That is, the MPEG A / V decoder 232 internally uses the PES as a sub-unit of the MPEG compressed video stream (video PES), a picture layer as a component of the ES, a slice layer as a lower layer of the picture layer, and a lower portion thereof. After sequentially separating and processing the macroblock layer, which is a hierarchical layer, and outputting the video data which has been expanded as it is, the decoding and dividing the video stream by layer is called decoding.

Here, some types of buffers are required for the restoration of the video stream, which are located in the SDRAM 231.

Accordingly, the NTSC encoder 233 converts the MPEG video data from the MPEG A / V decoder 232 into an analog signal and then generates the NC signals Y, C, and CVBS.

The digital-to-analog converter 234 outputs an analog audio signal by inputting MPEG audio data (SD, CLK, R / L) from the MPEG A / V decoder 232.

In addition, since the microcomputer 222 may be connected to the NTSC encoder 233 through a bus, a result of performing a user command input to the interface unit 221 while transmitting an MPEG compressed video / audio stream to the MPEG A / V decoder 232. Graphic information indicating may be transmitted to the NTSC encoder 233.

If the user screen mode is set, the microcomputer 222 recognized through the interface unit 221 generates graphic information from the databased information and outputs the graphic information to the NTSC encoder 233 through the IIC bus.

At this time, the MPEG A / V decoder 232 decodes the MPEG compressed video / audio stream from the microcomputer 222 to restore the original MPEG video / audio data and output the MPEG video data to the NTSC encoder 233. do.

Accordingly, the NTSC encoder 233 synthesizes the reconstructed video signal from the MPEG A / V decoder 232 and the graphic video signal from the microcomputer 222 to output the NTS signal (Y / C, CVBS). Information is displayed.

The NTSC encoder 233 is replaced with an encoder of PAL or SECAM type according to the broadcasting area.

However, in the conventional technology, when a still mode is set, a predetermined amount of video is repeatedly displayed, but there is a disadvantage in that the viewer feels bored when there is no signal during TV viewing or when the channel and input terminal are changed.

Therefore, in order to solve the conventional problem, when the user sets up image acquisition, the user detects a specific signal when decoding specific picture data, acquires a specific picture, and stores the information together with the relevant information of the acquired image. An object of the present invention is to provide an image acquisition / reproduction method of a digital broadcast receiver, which can easily find a desired image.

Another object of the present invention is to menu the information on the acquired image as a list and display the desired image on the screen by selecting an item of the list.

1 is an exemplary view showing a format of a digital broadcast signal.

FIG. 2 is an exemplary diagram illustrating a format of each packet included in the MPEG2 TS in FIG. 1. FIG.

FIG. 3 is an exemplary diagram illustrating a format of an ES included in a video PES in FIG. 2. FIG.

4 is a block diagram of a general digital broadcast transmitter.

5 is a block diagram of a signal processing apparatus of a conventional digital broadcast receiver.

6 is a block diagram of an apparatus according to an embodiment of the present invention.

7 is an operation flowchart showing a process for image acquisition in the present invention.

FIG. 8 is an exemplary view illustrating a storage structure of an image acquisition flash memory in FIG. 7; FIG.

9 is an exemplary view showing a process for displaying an acquired image in the present invention.

Explanation of symbols on the main parts of the drawings

311 tuner 312 analog-to-digital converter

313: link unit 321: interface unit

322: microcomputer 323,335: flash memory

324: DRAM 331: SDRAM

332: MPEG A / V Decoder 333: NTSC Encoder

334: Digital to Analog Converters

According to an aspect of the present invention, there is provided a method for determining an image acquisition request in a normal operation to achieve the above object, and when determining a request for image acquisition, a second port for determining whether a specific port of an MPEG A / V decoder has a predetermined level is determined. And if the specific port of the MPEG A / V decoder is at a certain level, reading the status register of the decoder to determine whether the desired picture is decoded; and if the decoding of the desired picture is determined as the decoding of the desired picture, the specific port of the decoder is at a predetermined level. Acquiring the decoded I-picture data during the process, and storing the relevant information of the acquired image together in a separate flash memory when the desired image is obtained.

In addition, the present invention is to determine whether to request the video playback in order to achieve the above object, to display the list of the acquired video when determining the video playback request, the step of determining the item selection of the list And displaying the acquired image on the sub screen whenever each item of the list is selected.

Hereinafter, the present invention will be described in detail with reference to the drawings.

Fig. 6 is a block diagram of a device showing an embodiment of the present invention. As shown therein, a tuner 311 tunes a desired channel from a broadcast signal received by an antenna, and a tuner signal of the tuner 311 in digital form. The analog-to-digital converter 312 converts the signal to the signal of the signal, the link unit 313 for demodulating the output signal of the analog-to-digital converter 312 to correct an error, and the MPEG-compressed video and audio stream. MPEG A / V decoder 332 which temporarily stores a specific port and maintains the level of a specific port while decoding a specific picture while temporarily storing it in the MPEG A / V decoder 332. NTSC encoder 333 for signal processing the original MPEG video data output from the NTSC signal (Y, C, CVBS) and the signals SD, CLK, R / in the MPEG A / V decoder 332. Input L) to analog voice signal (R, L) A digital-to-analog converter 334, an acquired image flash memory 335 for compressing and storing a desired image, an interface unit 321 for inputting a user command from a remote controller or a keypad, and this interface. In the case of channel selection by checking the output signal of the unit 321, the tuner 311 is controlled, and the output signal of the link unit 313 is demultiplexed into an MPEG compressed video, an audio stream, and additional information, and then the MPEG is controlled. The compressed video and audio streams are output to the MPEG A / V decoder 332, and the additional information is databased into information that can be provided to viewers. Check the level of the port to view the I picture data decoded by the MPEG A / V decoder 332 and the related information extracted from the additional information while the port maintains the specific level. The microcomputer 322 which stores the acquired image flash memory 335, the flash memory 323 which stores the execution program of the microcomputer 322, and the variable according to the signal processing of the microcomputer 322 It consists of a DRAM (DRAM) 324 to store.

In addition, when the user screen mode is set when the image acquisition is completed, the microcomputer 322 transmits the graphic information to the NTSC encoder 333 via the IIC bus for display on a screen of a display device (not shown). When the information to be stored together with the acquired image is input by the keypad or the remote controller, the user input information is added to the related information stored in the flash memory 335.

Referring to the operation and effect of the embodiment of the present invention configured as described above are as follows.

In the normal mode of the present invention, an image of broadcasting of a channel selected by a user through a tuner 321, a link unit 313, a microcomputer 322, an MPEG A / V decoder 332, and an NTSC encoder 333 is sequentially provided. Is displayed on a display device (not shown), which is the same as the operation of the prior art.

The present invention provides an image acquisition method and a method for displaying the obtained image, which will be described below.

An MPEG-2 standard video packet (or video PES) is composed of a video header and a video ES. The video ES is composed of picture layer data, and the picture layer data is composed of a picture header and the rest of the picture as illustrated in FIG.

The picture header contains various pieces of information, and one of the important pieces of information is a picture type. There are three types of pictures, I picture, P picture, and B picture.

Here, the I picture compresses one frame of the original image as it is, the P picture compresses the difference of motion by estimating the motion of the image based on the I picture, and the B picture compresses the difference of I and P. The motion difference is compressed by using a picture or P and P pictures in both directions before and after temporally.

Therefore, in order to acquire an image in the present invention, an I picture may be acquired, and the reason thereof is as follows.

If the scene at the moment when the viewer requests the image acquisition is a P or B picture, I picture or I picture and several P pictures are required to restore the picture.

Therefore, the digital image receiver should always be prepared for the acquisition command of the viewer, which may occur when the I picture or the P picture is input, whenever the I picture or the P picture is input, in order to acquire the B picture or the P picture.

Therefore, in such a case, the microcomputer of the system must determine and process the type of the picture whenever each picture is input. Since the input of the picture occurs very frequently, the determination and execution of the processing function may cause the microcomputer to receive the broadcast. The likelihood of causing serious impairments in the performance of other necessary functions is increased.

Since there is usually one I picture for every 15 pictures (i.e. for every 15 frames), the maximum frame difference from an I picture is 15 frames, even if the scene at the moment the viewer requested acquisition is a P or B picture. Since the frame difference is almost indistinguishable from the eye, even if the I picture is a representative value in all cases, it is not a problem.

Therefore, on the basis of the above reason, in the present invention, when the viewer requests the image acquisition, the I picture is decoded by the MPEG A / V decoder 332 under the control of the microcomputer 332.

In addition, in the present invention, a specific port of the MPEG A / V decoder 323 is checked for image acquisition, for the following reason.

The MPEG A / V decoder 332 decodes a PES level or lower and is provided with status registers for grasping the current decoding state among several registers provided therein.

Therefore, when the MPEG A / V decoder 332 is decoding the picture level, one of the state registers provided therein is recorded with the type of the picture being decoded.

In other words, if the MPEG A / V decoder 332 is currently decoding an I picture, it is recorded in a specific status register that the I picture is being decoded, whereas the B picture or P picture if it is decoding a B picture or a P picture. It is recording the state that it is decoding.

Therefore, in order to acquire the I picture, the microcomputer 322 grasps the picture information recorded in the specific state register of the MPEG A / V decoder 332, and the MPEG A / V decoder 332 is currently decoding the I picture. In this case, the decoded I picture data may be stored in the flash memory 335.

However, since most of the MPEG A / V decoder 332 is designed to output a specific signal through a specific port while decoding one picture, the microcomputer 322 always identifies the MPEG A / V decoder 332. It is only necessary to read the status register of the MPEG A / V decoder 332 to store the desired I picture in the flash memory 335 only when a specific signal generated during the decoding of the I picture is checked.

As a result, the burden on the microcomputer 322 to always read the status register in the MPEG A / V decoder 332 is eliminated.

In addition, since one picture frame is configured by combining several picture packets, the MPEG A / V decoder 332 outputs the same signal to a specific port while packets of the same type are continuously input.

Accordingly, the microcomputer 322 may store the picture data decoded by the MPEG A / V decoder 332 in the flash memory 335 while a specific port of the MPEG A / V decoder 332 outputs the same signal. .

That is, the image acquisition process as described above is performed in the same process as the operation flowchart of FIG. 7.

First, the microcomputer 322 determines the image acquisition request by the user by checking the output signal of the interface unit 321 while restoring the video and audio of the currently tuned broadcast by controlling the overall operation of the system.

At this time, upon recognizing a capture command for acquiring an image, the microcomputer 322 checks a specific port of the MPEG A / V decoder 323 and checks whether it is at a specific level.

Accordingly, if the specific port of the MPEG A / V decoder 323 is at a certain level, the microcomputer 322 checks the specific status register in the MPEG A / V decoder 323 to determine whether the picture currently being decoded is an I picture. do.

If the current decoded image is not an I picture, the microcomputer 322 repeats the operation of checking a specific status register in the MPEG A / V decoder 323.

Subsequently, if the current state to be decoded is recognized as an I picture by checking a specific status register in the MPEG A / V decoder 323, the microcomputer 322 determines that the specific port of the MPEG A / V decoder 323 is at a specific level. During the maintenance, the I picture data decoded by the MPEG A / V decoder 323 is stored in the image acquisition flash memory 335.

Thereafter, when a specific port of the MPEG A / V decoder 323 is released from the specific level, the microcomputer 322 stops the image storing operation to the flash memory 335.

The image acquisition process as described above is repeatedly performed whenever the user requests image acquisition.

In addition, when the picture data acquired through the same process as the operation flowchart of FIG. 7 is stored, the related information is stored together. The related information is classified into two types as follows.

1. Information obtained from additional information (PSI) existing in the original digital broadcast signal. 2. Information entered directly by the viewer.

The process of storing such related information is as follows.

First, when the image acquisition is completed, the microcomputer 322 determines the current time (time at which the image was acquired) from the additional information PSI included in the video packet (or video PES) as related information to be stored with the acquired image. The broadcasting station, broadcasting program name, etc., which have acquired the image, are extracted and stored in the flash memory 335.

If the user sets the user screen mode to input the desired information when the image acquisition is completed, the microcomputer 322 reads the relevant information stored in the flash memory 335 and generates an on-screen image to generate the NTSC encoder. To 333.

At this time, the NTSC encoder 333 displays the graphic image from the microcomputer 322 on the screen of the display device (not shown), and the user inputs information to be stored together with the acquired image by using a keypad or a remote controller. .

Accordingly, the microcomputer 322 stores the input information of the user in the flash memory 335 in addition to the related information.

That is, in the present invention, the current time extracted from the additional information PSI included in the video packet (or video PES) as the related information to be stored together with the acquired image (same as the time at which the image was obtained), the broadcasting station that acquired the image, The program name and the like are basically stored, and the information directly input by the viewer is also stored in the flash memory 335 together.

The structure of the acquired image and related information stored in the flash memory 335 is the same as the example of FIG. 8.

Meanwhile, in the present invention, reproduction of the acquired image basically has a form of a graphical user interface (GUI), and the process thereof will be described below.

First, when a viewer sets a menu display with a remote controller or a keypad to reproduce an acquired image, the microcomputer 322 outputs the on-screen image of the initial menu to the NTSC encoder 333 to display on the screen of the display device (not shown). An initial menu as shown in Fig. 9A is displayed.

At this time, when the user selects the image playback in the initial menu, the microcomputer 322 reads and texts each item of the relevant information on the acquired image currently stored in the flash memory 35 and converts the characterized list into an on-screen image. By making the output to the NTSC encoder 333, a list as shown in the example of Fig. 9B is displayed on the screen of the display device (not shown).

Accordingly, when the user selects an item of an acquired image to be played back using a keypad or a remote controller while viewing the list displayed on the screen, the microcomputer 322 NTSC displays the corresponding image of the selected item among the acquired images stored in the flash memory 335. It outputs to the encoder 333 and displays it on the screen of a display device (not shown).

At this time, whenever the user selects each item of the list, the microcomputer 322 outputs the corresponding image of the selected item among the acquired images stored in the flash memory 335 to the NTSC encoder 333 to display the display device (not shown). On the screen, the NTSC encoder 333 combines the acquired image with the main image under the control of the microcomputer 322 to display the acquired image on the sub picture PIP as illustrated in FIG. have.

Therefore, whenever an item of the list is selected, the acquired image is displayed on the sub-screen so that the viewer can easily find and play the desired image even if the viewer forgets what the acquired image is.

Thereafter, when the viewer recognizes the acquired image to be played back through the list search process and presses a selection button in the corresponding item, the viewer displays the stored acquired image on the entire screen.

As described in detail above, the present invention enables the viewer to acquire and store an image of a desired scene while watching a broadcast, and then play the scene again to enjoy the scene. It is effective to provide satisfaction to the viewer.

Claims (10)

A first step of determining whether to request an image acquisition; a second step of determining whether a specific port of the MPEG A / V decoder is at a predetermined level when the request for image acquisition is determined; and And storing the specific picture data decoded during the predetermined level of the specific port in a separate flash memory when the specific port reaches a predetermined level. The method of claim 1, wherein the specific picture data is I picture data. The method of claim 1, further comprising storing related information of the acquired image in a separate flash memory when the acquisition of the desired image is completed. 4. The method of claim 3, wherein the related information is information extracted from additional information (PSI) (image acquisition time, broadcast station name, broadcast program name). The method of claim 4, wherein the related information further comprises user input information. A first step of determining whether to request an image acquisition; a second step of determining whether a specific port of the MPEG A / V decoder is at a predetermined level when the request for image acquisition is determined; and A third step of checking whether a specific port is decoded by reading a status register inside the decoder when the specific port is at a predetermined level; and when the specific port of the decoder is decoded during a predetermined level when the decoding is performed on the specific picture data. And acquiring the picture data and storing the picture data together with the related information of the picture data in a separate flash memory. The method of claim 6, further comprising determining whether the user screen mode is set when acquiring a desired image is completed, and adding input information by the user to the related information in the user screen mode. Image acquisition method of a broadcast receiver. A method of acquiring and storing an image and displaying the image on a viewer screen, the method comprising: a first step of determining whether an acquired image is reproduced; a second step of displaying a list of acquired images when determining a reproduction request of the acquired image; Selecting an item in the list and performing a third step of displaying an acquired image corresponding to the item; The method of claim 8, wherein the third step includes displaying a corresponding acquired image on the sub-screen every time an item of the list is selected, and pressing the select button for the item of the acquired image displayed above to display the acquired image as a whole. And a second process of displaying on the screen. 10. The method of claim 8, wherein the list of acquired images in the second step is obtained by reading and texting related information.