Abstract:
An image mode selecting method and apparatus for a television receiver which can display n images corresponding to n image modes on a screen utilizing a picture-in-picture (PIP) display function, so that a user can easily select an optimum image among the displayed images. According to the method and apparatus, the n images corresponding to the n image modes are displayed on the n PIP regions of the screen, respectively, by pressing an image selection key, and then the optimum image among the n displayed images can be selected by pressing a numeral key corresponding to the selected image.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to image mode selection for television receivers. In particular, the present invention relates to a method and apparatus for selecting an image mode which can display a plurality of images on a plurality of divided portions of a display screen, respectively, whereby an optimum image among the displayed images can be selected by a user. 
     2. Description of the Prior Art 
     Generally, a television receiver, as shown in FIG. 1, is provided with a tuner section  101  for selecting a desired channel signal from radio frequency (RF) broadcasting signals received through an antenna ANT and converting the selected channel signal to video and audio intermediate frequency (IF) signals, an audio IF section  102  for processing the audio IF signal provided from the tuner section  101  to provide an audio signal to a loudspeaker  103 , a video IF section  104  for processing the video IF signal provided from the tuner section  101  to provide a video signal, a color picture tube (CPT) processing section  105  for processing the video signal provided from the video IF section  104  so that the video signal is suitable for being displayed on a color picture tube (CPT)  106 , a remote controller  107  for selecting a desired function or channel, a remote controller receiving section  108  for receiving an output signal of the remote controller  107 , and a microcomputer  109  for receiving an output signal of the remote controller receiving section  108  and controlling the overall operation of the television receiver, the microcomputer  109  discriminating an input of an image mode selection key through the remote controller  107  and providing image data corresponding to the selected image mode to the video IF section  104 . 
     The image mode selecting operation performed by the conventional television receiver as constructed above will now be explained. 
     The tuner section  101  selects a channel broadcasting signal among the broadcasting signals received through the antenna ANT, and converts the selected channel broadcasting signal to video and audio IF signals. The audio IF section  102  processes the audio IF signal outputted from the tuner section  101  to provide an audio signal to the loudspeaker  103 . The video IF section  104  processes the video IF signal outputted from the tuner section  101  to provide a video signal. This video signal is inputted to the CPT processing section  105  and is converted to a format suitable for display on the CPT  106 . 
     At this time, if a user is not satisfied with the present display state of the image being displayed on the CPT  106  screen, and thus enters the image mode selection key in the remote controller  107  to select an optimum image mode, the microcomputer  109  receives the image mode selection key signal through the remote controller receiving section  108 , and determines the present mode as an image selection mode. 
     If the image selection mode is determined as above, the microcomputer  109  outputs to the video IF section  104  a pulse-width-modulated (PWM) signal corresponding to the present image mode, so that the present image and an on-screen display (OSD) for identifying that the present mode is the image selection mode are displayed on the CPT  106  screen. 
     Thereafter, if the user enters the image mode selection key in the remote controller  107  again, the microcomputer  109  outputs a PWM signal corresponding to another image mode to the video IF section  104 . As a result, every time when the image selection key is entered, the selected image mode is displayed on the CPT  106  screen in the order of “image  1 →image  2 →image  3 → . . . image n”. Accordingly, only one image is displayed on the CPT  106  screen in accordance with the input of the image selection key. 
     The user may select an optimum image among the images which are sequentially displayed on the CPT  106  screen in accordance with the input of the image selection key in the remote controller  107 . 
     However, the conventional image mode selecting method for a television receiver has drawbacks in that since only one image is displayed on the screen by each input of the image selection key, the user may have difficulty in accurately comparing a plurality of images with one another, and thus the user&#39;s selection of the optimum image among them will become difficult. Especially, in the event that the image data is precisely changed for each image mode, it becomes more difficult for the user to recognize such an image change for each image mode. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to solve the problems involved in the prior art, and to provide a method and apparatus for selecting an image mode for a television receiver which can display n images on n divided picture-in-picture (PIP) regions of a display screen, respectively, by entering an image selection key, whereby a user can easily select an optimum image by comparing the n images with one another which are simultaneously displayed on the display screen. 
     In order to achieve the above object, the present invention can be implemented by providing hardware capable of performing an n-PIP-scene process, and software capable of controlling an n-image display and selection. 
     In one aspect of the present invention, there is provided an image mode selecting method for a television receiver comprising the steps of: 
     determining whether or not an image selection key is inputted; 
     displaying in order n images on corresponding picture-in-picture (PIP) regions of a display screen if it is determined that the image selection key is inputted; 
     determining whether or not the present on-screen display (OSD) is for an image selection mode if it is determined that the image selection key is not inputted; 
     determining whether or not a numeral key corresponding to an image to be selected is inputted if it is determined that the present OSD is for the image selection mode; and 
     setting the image mode corresponding to the inputted numeral key if it is determined that the numeral key is inputted, turning off the PIP-scene process, and clearing the OSD displayed on the display screen. 
     In another aspect of the present invention, there is provided an image mode selecting apparatus for a television receiver comprising: 
     a tuner for selecting a channel broadcasting signal from channel broadcasting signals received through an antenna by tuning, and converting said selected channel broadcasting signal to video and audio intermediate frequency (IF) signals; 
     audio IF processing means for processing said audio IF signal provided from said tuner to provide an audio signal; 
     video IF processing means for processing said video IF signal provided from said tuner to provide main color signals; 
     video encoding means for converting said color signals to a composite video signal by compression of said color signals provided from said video IF processing means; 
     picture-in-picture (PIP) processing means for converting said composite video signal provided from said video encoding means to sub-color signals in accordance with position data; 
     color picture tube (CPT) processing means for synthesizing said main color signals from said video IF processing means and said sub-color signals from said PIP processing means, and converting said synthesized color signals into a format suitable for displaying on a CPT; 
     key input means for entering an image selection key and numeral keys corresponding to n image modes, respectively; and 
     control means for controlling said video IF processing means and said PIP processing means so that n image modes are displayed on corresponding PIP regions of a screen of said CPT when said image selection key is inputted, and for controlling said video IF processing means and said PIP processing means so that an image mode selected among said n image modes is displayed on said CPT screen when one of said numeral keys corresponding to said selected image mode is inputted. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above objects, other features, and advantages of the present invention will become more apparent through the following description of the preferred embodiment of the present invention made with reference to the attached drawings, in which: 
     FIG. 1 is a block diagram illustrating the construction of a television receiver implementing a conventional image mode selecting method. 
     FIG. 2 is an algorithm diagram incorporating a conventional image mode selecting method. 
     FIG. 3 is a view explaining the image display state when an image selection mode is set according to a conventional method. 
     FIG. 4 is a block diagram illustrating the construction of the image mode selecting apparatus according to the present invention. 
     FIG. 5 is a view explaining the image display state when an image selection mode is set according to the present invention. 
     FIG. 6 is an algorithm diagram incorporating the image mode selecting method according to the present invention. 
     FIG. 7 is a table exemplifying the image data for each image mode according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 4 is a block diagram of the image mode selecting apparatus for a television receiver according to the present invention. 
     Referring to FIG. 4, the image mode selecting apparatus according to the present invention is provided with a tuner  201  for selecting a channel broadcasting signal among high frequency channel broadcasting signals received through an antenna ANT by tuning and converting the selected channel broadcasting signal to video and audio IF signals, an audio IF processing section  202  for processing the audio IF signal outputted from the tuner  201  to provide an audio signal to a loudspeaker  203 , a video IF processing section  204  for processing the video IF signal provided from the tuner  201  to R, G, and B main color signals, and a video encoder  210  for converting the R, G, and B color signals provided from the video IF processing section  204  to a composite video signal by performing compression with respect to the R, G, and B color signals. 
     The image mode selecting apparatus according to the present invention is also provided with a PIP processing section  211  for converting the composite video signal provided from the video encoder  210  to R, G, and B sub-color signals in accordance with position data, a CPT processing section  205  for synthesizing the main color signals from the video IF processing section  204  and the sub-color signals from the PIP processing section  211  to provide the synthesized color signals to a CPT  206 , a remote controller  207  for entering an image selection key and numeral keys for selecting one of n image modes, a remote controller receiving section  208  for receiving the output signal of the remote controller  207 , and a microcomputer  209  for providing a control signal corresponding to the present image mode to the video IF processing section  204 , and providing another control signal corresponding to a selected image mode to the video IF processing section  204  if it is determined that the image selection key is inputted by checking the output signal of the remote controller receiving section  208 , the microcomputer  209  providing the position data for displaying the corresponding image mode to the PIP processing section  211 . 
     The operation of the image mode selecting apparatus according to the present invention as constructed above will be explained with reference to FIGS. 4 to  7 . 
     If a user selects a desired channel using the remote controller  207 , the remote control signal outputted from the remote controller  207  is received to the remote controller receiving section  208 . The microcomputer  209  recognizes the selected channel from the output signal of the remote controller receiving section  208 , and outputs a control signal for selecting the corresponding channel broadcasting signal to the tuner  201 . 
     The tuner  201  selects the corresponding channel broadcasting signal among the broadcasting signals received through the antenna ANT in accordance with the control signal received from the microcomputer  209 , and converts the channel broadcasting signal to the video and audio IF signals. 
     The audio IF processing section  202  processes the audio IF signal outputted from the tuner  201  and provides an audio signal to the loudspeaker  203 . The video IF section  204  processes and converts the video IF signal outputted from the tuner  201  to the R, G, and B color signals in accordance with the control signal provided from the microcomputer  209  to provide the R, G, and B color signals to the CPT processing section  205 . The CPT processing section  205  converts the inputted color signals into a format suitable for displaying on the CPT  206 , and provides the color signals to the CPT  206 , so that the image is displayed on the CPT screen. 
     At this time, if a user is not satisfied with the present state of the image being displayed on the CPT  206  screen, and thus enters the image selection key in the remote controller  207 , the microcomputer  209  recognizes that the image selection mode is selected (step S 1  in FIG.  6 ). At this time, if a PIP-scene is displayed on the screen, the microcomputer  209  controls the PIP processing section  211  to turn off the PIP-scene (step S 2  in FIG.  6 ), outputs to the video IF processing section  204  a PWM-modulated image data corresponding to a first image (step S 3  in FIG.  6 ), and outputs to the PIP processing section  211  a position data for displaying the first image (step S 4  in FIG.  6 ). 
     The video IF processing section  204  processes the image data provided from the tuner  201  in compliance with the PWM-modulated data provided from the microcomputer  209 , and outputs the R, G, and B color signals processed as above to the CPT processing section  205  and the video encoder  210 . 
     At this time, the video encoder  210  converts the R, G, and B color signals inputted from the video IF processing section  204  to a composite video signal CVBS by compressing the inputted R, G, and B color signals by a compression factor of 1/n, and the PIP processing section  211  outputs R, G, and B color signals corresponding to the composite video signal to the CPT processing section  205  so that the compressed composite video signal is displayed on a corresponding PIP region of the CPT  206  screen by calculating the position data provided from the microcomputer  209 . 
     The CPT processing section  205  synthesizes the R, G, and B main color signals outputted from the video IF processing section  204  and the R, G and B sub-color signals outputted from the PIP processing section  211  to provide the synthesized color signals to the CPT  206 . Accordingly, the first image corresponding to the first image mode data as shown in FIG. 7 is displayed on the CPT  206  screen as shown in FIG.  5 . 
     Thereafter, if it is determined that the first image has been displayed for a predetermined time, the microcomputer  209  converts the first image being displayed to a still image (step S 5  in FIG.  6 ), and then outputs a second PWM-modulated image mode data as shown in FIG. 7 to the video IF processing section  204  so that a second image corresponding to the second image mode data is displayed on a corresponding PIP region of the CPT  206  screen (step S 6  in FIG.  6 ). The second image is displayed on the corresponding PIP region as shown in FIG. 5 in the same manner as the first image display (step S 7  in FIG.  6 ). 
     Thereafter, if the second image is converted to a still image (step S 8  in FIG.  6 ), the microcomputer  209  performs a control operation for displaying a third image. As shown in FIG. 5, such a display operation is repeated until the n-th image is displayed on the CPT screen as a still image as shown in FIG. 5 (steps S 9 , S 10 , and S 11  in FIG.  6 ). 
     Specifically, if the image selection key in the remote controller  207  is pressed, the microcomputer  209  sequentially outputs the PWM-modulated signals corresponding to the first to n-th images to the video IF processing section  204 , while it sequentially outputs the position data for the corresponding images to the PIP processing section  211 . At this time, after a predetermined time has elapsed since an image was displayed on a corresponding PIP region of the CPT screen, the displayed image is fixed as a still image. By repeating the above operation n times, all the first to n-th images are displayed on the CPT screen as still images as shown in FIG.  5 . 
     As the n images are simultaneously displayed on the screen of the CPT  206  as described above, the user can compare the image display states of the n images on the CPT  206  screen simultaneously. At this time, the microcomputer  209  outputs a PWM-modulated signal to the video IF processing section  204  as well as outputs the position data to the PIP processing section  211  so that the on-screen characters such as “PLEASE SELECT THE BEST IMAGE BY ENTERING A CORRESPONDING NUMERAL KEY” are displayed on the predetermined OSD region of the CPT screen as shown in FIG. 5 (step S 12  in FIG.  6 ). 
     In the event that the present OSD is for the image selection mode, the microcomputer  209  recognizes it (step S 13  in FIG.  6 ), and thus waits for the entry of a numeral key. 
     In this state, if the user enters a numeral key corresponding to the optimum image by comparing the n images displayed on the CPT  206  screen, the microcomputer  209  recognizes it (step S 14  in FIG.  6 ), and sets the image mode selected by the corresponding numeral key (step S 15  in FIG.  6 ). Specifically, the microcomputer  209  controls the PIP processing section  211  to turn off the PIP-scenes (step S 16  in FIG.  6 ), and outputs the PWM-modulated signal corresponding to the selected image mode to the video IF processing section  204  (step S 17  in FIG.  6 ), and then clears the OSD (step S 18  in FIG. 6) to complete the image selection operation. 
     Thereafter, the optimum image corresponding to the image mode data selected by the user is displayed on the screen of the CPT  206 . 
     From the foregoing, it will be apparent that the present invention provides advantages in that it can display n images for the user&#39;s selection on the screen simultaneously, and thus the user can easily select the optimum image among them, providing convenience in use. 
     While the present invention has been described and illustrated herein with reference to the preferred embodiment 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.