KR0123756B1 - Apparatus of image signal receiving having before picture search function - Google Patents

Abstract

The present invention provides a video signal receiver with previous picture searching function which stores picture information in an extra memory or a PIP memory, and when searching the information of a previous picture, reads out the stored picture information. This receiver includes a memory with plural memory areas divided by the unit of a picture; a previous picture searching key producing a previous picture searching instruction; a memory controller storing video signals of a channel currently turned at normality periodically in the memory area and reading the latest one of the picture information held in the memory areas in response to key input of the previous picture searching key; and an output part outputting the picture information to be displayed on the current screen.

Description

Video signal receiver with previous screen search function

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

2 is a detailed block diagram of an address generator that is a part of the memory controller 110 shown in FIG.

3A to 3E are waveform diagrams for starting screen search.

4A to 4D are waveform diagrams during screen navigation.

5 is a block diagram according to another embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

100: memory 110: memory control unit

120: MUX 500: Memory

510: memory controller 520: PIP screen signal processor

530: MUX

The present invention relates to a video signal receiving apparatus, and more particularly, to a video signal receiving apparatus having a previous screen searching function for storing screen information using an internal memory.

In the related art, when a viewer watches a television and wants to search a previous screen, the viewer searches for a content recorded in advance in a video cassette recorder (VCR). However, since a digital signal processing television includes a memory, storing the screen information of the channel being watched in the memory enables the previous screen to be searched without the VCR.

Accordingly, an object of the present invention is to provide a video signal receiving apparatus having a previous screen search function by reading the screen information stored in the memory when the screen information of the channel currently being watched is stored in the memory and the previous screen search is desired.

Another object of the present invention is to provide a video signal receiving apparatus having a previous screen search function for searching a screen to a PIP screen by using a picture in picture (PIP) function.

In order to achieve the above object, a video signal receiving apparatus having a previous screen searching function according to the present invention comprises: a memory including a plurality of memory regions divided by a screen unit; Previous screen search key for generating previous screen search command; Normally, the video signal of the channel currently being tuned is recorded in the plurality of memory areas every predetermined time, and from the most recent screen information among the screen information stored in the plurality of memory areas in response to the operation of the previous screen search key. A memory control unit to read out; And an output unit configured to output the screen information read from the memory controller to be displayed on a screen currently being viewed.

In order to achieve the above object, a video signal receiving apparatus having a previous screen search function according to the present invention inputs screen information of a plurality of channels, and the user selects a main screen and a sub-screen to attach a predetermined area within an area occupied by the main screen. A video signal receiving apparatus having a picture in picture (PIP) function for splitting and displaying a screen so as to occupy a screen, comprising: a memory in which a plurality of memory areas are divided on a screen basis; A multi-channel key for multi-channel viewing and a previous screen search key for generating a previous screen search command; Normally, the video signal of the channel currently being tuned is recorded in the plurality of memory areas every predetermined time, and the multi-channel video signal is recorded in the plurality of memory areas every predetermined time in response to the operation of the multi-channel key. A memory controller which reads from the most recent screen information among screen information stored in the plurality of memory areas in response to the operation of the previous screen search key; And an output unit configured to output the screen information read from the memory controller to be displayed on a screen currently being viewed in a screen division method.

An embodiment of the present invention will be described with reference to the accompanying drawings.

1 is a block diagram according to an exemplary embodiment of the present invention, which includes a memory 100 for storing screen information on a field-by-field basis, and a memory controller 110 for controlling reading and storing screen information in the memory 100. ) And a multiplex (MUX) 120 that selectively outputs screen information of the channel currently being viewed and previous screen information.

2 is a detailed block diagram of an address generator (not shown) embedded in the memory controller 120. The counter 200, the field address generator 210, the pixel address generator 220, and the address generation controller 230 are shown in FIG. It consists of.

Another embodiment of the present invention is a memory control unit 510 for storing the screen information in the unit of the field as shown in Figure 5 and the memory control unit 510 for controlling the reading and storage of the screen in the memory 500 and PIP sub-screen signal processing unit 520 for processing input channel screen information as sub-screen during PIP signal processing, multiplex (MUX) 530 for selectively outputting PIP screen information and screen search information, main screen and sub-screen A mixing unit 540 for mixing the screen and a selecting unit 550 for selecting the mixed screen and the normal screen.

Next, FIGS. 1 and 2 will be described with reference to FIGS. 3A to 4D.

In order to output the screen information to the image display unit (not shown) and simultaneously store the screen information in the memory 100, the memory controller 110 inputs the current channel information in units of screens and stores the screen information in the memory 100. . That is, the screen information received according to the address output from the address generator (not shown) in the memory controller 110 is stored in the memory 100 in units of fields.

This address generator generates an address for writing or reading the screen information as shown in FIG.

First, address generation for writing screen information will be described.

In the normal mode, that is, when there is no previous screen search signal SEARCH, the address generator generates an address for writing screen information. The previous screen search signal SERCH is generated by the operation of the previous screen search key (not shown). The counter 200 that counts the predetermined integer n generates a ripple carry (Figure 3b) after counting the predetermined integer n using the vertical synchronization signal V-SYNC as a clock. The counter 200 generates a ripple carry after a predetermined integer number of vertical synchronizations, i.e., every 1/60 x n seconds, which enables the field address generator 220. FIG. The storage interval of the field may be controlled by a predetermined integer n, and the storage time interval may vary according to the capacity of the memory. At this time, by adjusting the constant n, the displayed screen can be adjusted to a still image or a moving image. When the screen information is stored in every field, the moving image can be reproduced.

The field address generator 210 is enabled by the output signal of the counter 200 to generate a start address for each field as the field address and transmit it to the memory 100. As shown in FIG. 3D, the field address generator 210 generates a field address from field 1 to field k, and the memory 100 stores field screen information for recording accordingly.

When the address of one field is generated, the pixel address generator 220 generates a pixel address for storing a pixel corresponding to the field. At this time, the pixel address generator 220 sets the vertical synchronization signal V-SYNC to clear, and a logical product of the ripple carry and the data rate is given as a clock. It consists of a counter that counts. When the ripple carry occurs, the number of pixel bits according to the data change rate DATA RATE is counted and transmitted to the memory 100 during one period of the vertical synchronization signal V-SYNC. The memory 100 stores the pixel according to the pixel address generated by the pixel address generator 220 at the start address of one field generated by the field address generator 200.

The enable signal of the field address generator 210 and the clear signal and the clock signal of the pixel address generator 220 are controlled by the address generation controller 230.

The following describes address generation for reading the screen information.

In the previous screen search mode, that is, when there is a previous screen search signal SEARCH, the address generator generates an address for reading the screen information. At this time, the counter 200 does not operate and the previous screen search signal SEARCH directly becomes an enable signal of the field address generator 210 to generate the field address.

When the field address generator 210 is enabled, a start address for each field is generated as the field address and transmitted to the memory 100, and the memory 100 reads the field screen information accordingly.

At this time, if there is a previous screen search signal SEARCH, the pixel address generator 220 counts the number of pixel bits according to the data rate (DATA RATE) during one period of the vertical synchronization signal V-SYNC and transmits it to the memory 100. do. The memory 100 reads a pixel according to the pixel address generated by the pixel address generator 220 at the start address of one field generated by the field address generator 200. The previous screen search signal SEARCH includes a back screen search signal BACK-SEARCH and a forward screen search signal FORWARD-SEARCH, which are logical sum signals of the two signals. When the back screen search signal (BACK-SEARCH) is input, the down signal is inputted to the field address generator 210 so that the address decreases. When the forward screen search signal (FORWARD-SEARCH) is inputted, the address is increased. ) Signal is input to the field address generator 210.

When watching the screen of the desired channel in the normal mode, as described above, if the field address generator 210 generates the field address due to the ripple carry (Fig. 3B) output from the counter 200 of the address generator, the field screen accordingly Information (FIG. 3D) is stored in the memory 100. FIG. When a pause (figure 3c) signal is input for searching the previous screen, the controller 110 may apply the write control signal WE shown in FIG. 3a to stop storing screen information in the memory 100. Disable A field address of one field in which the most recent screen information is stored is generated, and the screen of one field stored at the address is read from the memory 100 and output to the image display unit. The field screen information read out according to the address is as shown in FIG. 3E. In other words, the moment the pause signal is sent, the screen is in a still state.

When the back screen search signal BACK-SEARCH (FIG. 4B) is input and the screen search mode is input, the memory controller 110 generates a decreasing address and displays screen information corresponding to the address from the memory 100 (4d). Read) and output to the image display unit through the MUX 120. When a forward screen search signal (FORWARD-SEARCH) (FIG. 4C) is input, an increasing address is generated, and the screen information corresponding to the address (FIG. 4D) is read from the memory 100, and the searched screen information is converted into MUX ( Output to the image display unit through 120. That is, after searching the screen by the back-screen search signal (BACK-SEARCH) to search the past screen, the screen after the desired screen can be seen by the forward screen-search signal (FORWARD-SEACH).

The MUX 120 outputs the screen information currently being viewed in the normal mode, and the screen information read from the memory 100 by the memory controller 110 when the previous screen search mode, that is, the previous screen search signal SEARCH is present. Outputs

5 is another embodiment of a previous picture searchable video signal receiving apparatus according to the present invention.

5 is an example applied to the sub picture signal processing circuit among the PIP signal processing circuits in a television having a PIP function. That is, the PIP signal processing inputs screen information of a plurality of channels so that a user selects a main screen and a sub-screen, and the sub-screen occupies a predetermined area within an area occupied by the main screen so that two screens can be simultaneously displayed on one screen. As it is a well-known technique as processing, detailed description is not carried out.

When the user selects and views a channel, the screen information is output to the image display unit (not shown), and at the same time, the screen information is transmitted through the A channel input to the memory controller 510 for storage in the memory 100. The memory controller 510 stores the screen information received in units of fields in the memory 500 according to the address output from the built-in address generator (not shown).

When the PIP normal mode is selected for the multi-channel screen viewing, the multi-channel screen control signal (MULTI-CH) is input to the memory controller 510 and the PIP sub-screen signal processor 520, respectively, and the screen of the channel selected as the sub-screen is selected. The information is transmitted through the B channel input to the PIP sub-screen signal processor 520. That is, in the PIP normal mode, image information input through the A channel is output to the main screen, and image information input through the B channel is signal-processed to the sub-screen and output to the image display unit through the MUX 530, and at the same time, the memory controller 510 stops storing image information input through the A channel viewed as the main screen and stores image information input through the B channel for the sub picture. The multi-channel screen control signal MULTI-CH is generated by the multi-channel key and the previous screen search signal SEARCH is generated by the previous screen search key. The screen information of the selected channel may be a channel viewed as the main screen or may be another channel.

When a pause signal is input for screen searching, the memory controller 510 stops storing B channel screen information in the memory 500 and generates a start address of a field in which the most recent screen information is stored. The screen of one field stored at the address is read from the memory 500.

When the back-screen search signal (BACK-SEARCH) is input, the screen search information corresponding to the address which decreases from the address where the most recent screen information is stored is read from the memory 500 to become sub-screen information through the MUX 530. When a forward screen search signal (FORWARD-SEARCH) is input, screen search information corresponding to an increasing address is read from the memory 500 to become sub-screen information through the MUX 530. The MUX 530 selects and outputs the PIP normal mode and the screen search mode in the PIP mode.

As described above, in the PIP mode, the sub-screen information output through the MUX 530 is mixed with the main screen information by the mixing unit 540 and output to the image display unit.

Even in the mode of viewing the screen using only the main screen instead of the PIP mode, the normal mode and the main screen search mode for watching the current viewing channel are possible.

In the normal mode, the current viewing screen flowing through the A channel is selected by the selector 550 and output to the display unit. In the main screen search mode, the screen information is output to the display unit in the normal mode and simultaneously stored in memory. The screen information stored in the 500 is read, selected by the selection unit 550 through the MUX 530, and output to the display unit.

As described above, the video signal receiving apparatus having the previous screen search function stores the screen information in a separate memory or a PIP memory, and reads the screen information stored in the memory when the screen information is to be searched. It is effective to search previous screen information.

Claims (7)

A video signal receiving device comprising: a memory in which a plurality of memory areas are divided by screen units; Previous screen search key for generating previous screen search command; Normally, the video signal of the channel currently being tuned is recorded in the plurality of memory areas every predetermined time, and the most recent screen information among the screen information stored in the plurality of memory areas in response to the operation of the previous screen search key. A memory controller to read from the memory; And an output unit for outputting the screen information read by the memory controller to be displayed on a screen currently being viewed. The image receiving apparatus having a previous screen search function of claim 1, wherein the memory controller comprises an address generator for generating an address for storing the screen information. 3. The apparatus of claim 2, wherein the address generator comprises: a counter for using the vertical synchronization signal V-SYNC as a clock and counting the desired number of predetermined first fields; A field address generator for generating a start address of a predetermined field by an enable signal; A pixel address generator for generating pixel addresses corresponding to the number of pixel bits to store and read pixels corresponding to a start address of a predetermined field output from the field address generator; And when it is not in the previous screen search mode, enable the field address generator by ripple carry, which is output when a desired first field is entered in the counter, and in the previous screen search mode in the previous screen search mode. And an address generation control unit for outputting a signal for enabling the field address generator by a signal SEARCH and for outputting a signal for controlling the pixel address generator according to a change rate of pixel data. Video receiver with previous screen search function. 4. The image receiving apparatus according to claim 3, wherein a still image and a moving image can be realized by adjusting the number of counting the counters. The apparatus of claim 1, wherein the previous screen search key performs a back search and a forward search. Video signal receiver with PIP (Picture In Picture) function that inputs screen information of a plurality of channels and the user selects the main screen and the sub-screen to divide the screen so that the sub-screen occupies a predetermined area within the area occupied by the main screen. A memory device comprising: a memory in which a plurality of memory areas are divided in units of screens; A multi-channel key for multi-channel viewing and a previous screen search key for generating a previous screen search command; Normally, the video signal of the channel currently being tuned is recorded in the plurality of memory areas every predetermined time, and the multi-channel video signal is recorded in the plurality of memory areas every predetermined time in response to the operation of the multi-channel key. A memory controller which reads from the latest screen information among screen information stored in the plurality of memory areas in response to the operation of the previous screen search key; And an output unit for outputting the screen information read from the memory controller to be displayed on a screen currently being viewed in a screen division method. 7. The apparatus of claim 6, wherein the output unit comprises a selection unit for selecting a screen and a main screen by screen division according to a multi-channel key.