Background of the Invention
This invention relates to the control and display of simultaneous plural video images on standard television equipment. The invention is a menu-driven multi-channel system in which a user easily selects channels by executing page up and page down commands.
The invention utilizes the picture-in-picture (PIP) function of existing and well-known television and video cassette recorder (VCR) technology. However, current technology displays only one sub-screen video image in the corner of a main screen. This invention displays more than one sub-screen in a main screen.
Summary of the Invention
An object of the invention is to display plural images on a single television screen.
Another object of the invention is to provide a convenient and easy-to-use menu system for television channel selection.
The invention provides a menu-type multi-channel video display system with page up/down mode comprising:
a skip memory,
a television tuner circuit,
a VCR signal processing circuit,
a switching circuit,
a PIP processing circuit
an input selector for the main screen,
an output selector for the sub-screen,
a microcomputer,
an on-screen display integrated circuit (OSDIC),
a mixer,
an audio circuit,
two tuners, and
a multiplexer.
Television channels are stored in the skip memory and assigned to a particular sub-screen. When the main screen is in PIP mode, and a multi-channel signal is received (from a user activating the multi-channel capability), the channels stored in skip memory are displayed in menu format, and can be selected by a novel page up/page down feature. This allows a user to easily and conveniently select the channel of his choice.
Brief Description of Drawings
FIGS. 1(A) and 1B are the waveforms for PIP and tuning for the exemplary embodiment of the present invention;
FIG. 1(C) is a representation of skip memory showing the position in the memory of various television channels.
FIG. 1(D) and 1E are status diagrams of multi-channel displays which are displayed in a main screen;
FIG. 2 (A) is a multi-channel strobing time chart;
FIG. 2 (B) is a reference time variation chart;
FIGS. 3(A), 3B, 3C and 3D are strobing charts of screens depicting the relationship of channel memory location to sub-screen location;
FIGS. 4A, 4B, 4C, 4D and 4E are the display charts of the main screen and sub-screen of tuner 1 and tuner 2;
FIGS. 5(A), 5C, 5B and 5D are hardware block diagrams of tuner 1 and tuner 2, respectively;
FIG. 6 is the total hardware block diagram for the multi-channel operation of this invention; and
FIGS. 7A and 7B are flow chart for the multi-channel operation of this invention.
Detailed Description of the Preferred Embodiment
Multi-channel mode is defined as n PIP sub-screens within a main screen, where each screen data of said PIP sub-screens is fetched from skip memory and displayed on the n PIP sub-screens at the same time.
Multi-channel mode can work on the PIP system with either tuner 1 or tuner 2. In multi-channel mode, the procedure of PIP control is as follows: when a multi-channel signal is received (as when a multi-channel key is actuated by a user), the multi-channel mode activates, and the skip memory is scanned. FIG. 4B describes the TV screen on which the main screen is a blue screen not receiving a broadcasting signal and the subscreens are multi-channel screens when the TV is turned on but is not in playback mode.
If there is a synchronized signal on a channel during the multi-channel mode, the channel becomes an effective channel as shown in timing diagram FIG. 1 (A):
In FIG. 1 (A), a multi-channel signal is received from a user. Following this signal, the user initiates a command to rotate the subscreen images (shown as .pi.). (1) is the current output of the PIP which corresponds to the current video sub-screen image. (2) is the requested data output or sub-screen image. (3) is an output signal activated when the tuner selects a channel. (4) represents an auto fine tuning (AFT) function completed after the channel is initially tuned. (5) represents the output of new data from the PIP replacing the prior image. It is assumed that the channels K to N are stored in the skip memory.
If no synchronized signal is found in the multi-channel mode, the channel becomes an ineffective channel as shown in FIG. 1 (B):
In FIG. 1-(B), 1'to 3' execute the same function as 1 to 3 of FIG. 1 (A). 4' is an output signal transmitted when no synchronized signal is found for the channel. 5' is an output signal jumping to a corresponding channel. 6' is an output signal for repeating the processes of 1' to 5' until the channel position having a synchronized signal is found, and 7' executes the process of FIG. 1-(A) when a synchronized signal is found.
Thus, the channels stored in the skip-memory become active as shown in FIG. 1 (C), where it is assumed that a NON-ADDED channel exists in position 3 and an ineffective channel is in position 4.
The NON-ADDED channel for a particular position, as shown, is defined as a channel not stored in the skip memory position.
The screen displayed by the operation of FIG. 1 (B) represents the display of channels K, L, N and O, as shown in FIG. 1-(D), where channel M, which does not have a synchronization signal of FIGS. 1-(A), is skipped. If a specific channel, for example channel N is selected from the displayed channels K, L, N, and O, by a user as shown in FIG. 1 (E), the selected channel N will then be displayed on the main screen.
FIGS. 2A and 2B show the waveform strobing time of multi-channel page up/page down operation. FIG. 2-(A) indicates the time (t) between successive channel selections.
FIG. 2-(B) shows the process of making the strobing time 0.2 second per step when the reference time of the changed time (At) is 1 second.
FIG. 3-(A) shows a skip memory consisting of 32 positions. FIG. 3-(B) shows one page of a TV screen on which four channels corresponding to four positions of the skip memory are displayed when the multi-channel feature is on.
It is possible to have P pages in the skip memory. If each page is defined to display 4 positions then 4P channel positions are available overall.
It was assumed in FIG. 3-(A) that position 4 and position 6 are non-added channels, and position 3 and position 10 are ineffective channels (having no synchronized signal). In the case of FIG. 3(B), each of four channels corresponding to four positions of the skip memory is displayed on one page of one TV screen, and it is possible to change the display by use of a page up or page down command.
The arrow of FIG. 3-(B) indicates the direction of the progress of strobing according to each channel.
FIG. 3-(C) shows the progress of the page up/down display. FIG. 3(D) indicates channels added to the skip memory.
If there are channels which do not have synchronous signals, the channel selector skips the channels. Thus, multi-channel mode is realized through the selection of positions having synchronous signals. As an example, if position 3 is an ineffective channel not having a synchronous signal, the channel is skipped over and an effective channel becomes active.
FIGS. 4A-4E show that multiple channels are displayed on a single screen.
FIG. 4A shows that a main screen is a playback screen (PB screen) and the sub-screens are multi-channel screens when tuner I is in play back mode.
FIG. 4C shows that the main screen is a playback (PB) screen and the sub-screens are multi-channel screens when tuner 2 is i n a playback mode.
FIG. 4D shows that, when there is a synchronizing signal in a main screen but the screen is not in the playback mode, the main screen displays tuner 1 or a single line and the sub-screen displays tuner 2.
FIG. 4E shows that, when there is a synchronizing signal in a main screen but the screen is not in the playback mode, the main screen displays tuner 2 or a line screen and the sub-screen displays tuner 1 or tuner 2.
FIG. 5 (A) is the tuner I system and FIG. 5-(B) is the tuner 2 system.
The tuner I system comprises a TV tuner circuit (501), a VCR signal processing circuit (502), a switching circuit (503) which selects blue-screen signal whose channel does not receive any broadcasting signal and is controlled by control signals for the main screen (Q7) and the sub-screen (Q6), and PIP block (504) for controlling the PIP.
The tuner 2 system comprises a main screen input selector (510), sub-screen output selector (511), signal processing block (512) for the VCR, switching circuit (513) which selects blue screen and is controlled by control signals for the main screen (Q7) and the subscreen (Q6), and PIP block (514) for processing them in PIP mode.
FIGS. 5C and 5D describe the operation of the tuner 1 and tuner 2 systems. "X" denotes a NORMAL state which has a synchronous signal and "Y" indicates an ineffective channel (having no synchronous signal ).
In the example of FIG. 5D, Q6 becomes L (low) and selects the playback (PB) screen as the main screen (during playback mode).
Q7 sets "X" to L if a synchronous signal is detected and selects the received channel as a sub-screen. If no synchronous signal is detected, then Q7 sets "Y" to (high) and selects blue-screen as a sub-screen.
Next, in the non-playback mode, Q6 and Q7 select either the received channel or blue screen as main screen or sub-screen according to whether a synchronous signal is found for the channel.
FIG. 6 shows a complete system composed of tuners 1 and 2 of FIGS. 5A-5D, and a microcomputer as a controller.
FIGS. 7A and 7B are flow charts for the system of FIG. 6.
If microcomputer (600) receives a channel input (step 701), it makes a decision whether the channel is the tuner 1 system or tuner 2 system (step 704). If the channel is tuner 1, it will determine whether the channel is in playback mode or not (step 705).
If it is not in playback mode, it selects the blue screen as a main screen (707). If the tuner system is tuner 2, it will determine whether the present mode is playback mode or not (step 708). If it is in playback mode, it selects the playback screen as the main screen (step 706). If it is not in playback mode, it will determine whether it is a main screen or a sub-screen (step 710).
If it is a main screen, it will check the existence of a synchronous signal (step 711). If no synchronous signal is detected, it selects the blue screen as the main screen (step 712). If the signal is a sub-screen (step 710), it reverses the mode of main/sub again (step 713) and selects a main screen according to the kind of input: tuner 1, tuner 2 or LINE (step 714).
If the input is tuner 1, the controller sets Q2 to H (step 715) and controls the tuner 1 (step 716).
If the input is tuner 2, the controller sets Q2 to low (step 717) and controls tuner 2 (step 718).
If the input is LINE, the controller keeps the previous state of Q2 (step 719) and does nothing for control (step 720).
When a main screen is selected according to the above process, the controller selects the blue screen as a main screen (step 722) according to the existence of a synchronous signal (step 721).
In contrast, the selection of a sub-screen is determined according to whether the output selector is tuner 1, tuner 2 or LINE (step 725).
If the output selector is tuner 1, the controller sets the signal Q2 to high (step 726), and controls tuner 1 (step 727). If it is tuner 2, the controller sets the signal Q2 low (step 728), and controls tuner 2 (step 729).
If it is LINE, the controller keeps the previous state of Q2 (step 730) and does nothing for control (step 731).
Selection of the sub-screen is completed according to the above process. The microcomputer executes the multi-channel screen according to screen 1, 2 or n (step 732), outputs both the current PIP data and the ROTATE key data (step 733), begins the selection of a tuner, performs the AFT action, and then outputs the PIP data again (step 734).
The microcomputer makes a decision based on the presence of a synchronous signal for the sub-screen (step 735).
If there is no synchronous signal, the controller jumps over to the next position (step 736). If there is a synchronous signal, the strobing is completed (step 736-1). The controller executes the strobing in progress (step 737), increases the content of the page counter (step 739) when the page up command is issued (step 738), decreases the content of the page counter (step 741) when the page down command is issued (step 740), and makes a decision as to the existence of multi-channel key input (step 742) inputted again. If there is input, the multi-channel function ceases (step 743), and the multi-channel function reverts to the state it was in prior to activation (step 745).
If there is no multi-channel key input (step 746), a corresponding channel is displayed on the corresponding screen (step 747).
Thus, according to this invention, a television screen is converted to a multi-channel display by using an existing PIP or multiscreen function, with the effect of improving the convenience and reliability of channel selection so that a user may easily select channels through a menu-based selection.