Nova Patents
EP0675645A2

Apparatus for discriminating video kinds and automatic aspect ratio discrimination apparatus and television receiver using it.

Abstract

The object of the present invention is to improve viewer's manipulation for television receivers such as wide television receivers, HighVision receivers by automatically discriminating the aspect ratio of the receiving signal at the receiver side. An automatic aspect ratio discrimination apparatus of the present invention can detect a picture starting position, a picture ending position and a subtitle ending position by generating three histograms segmented by two slice levels S and T at every line from a luminance signal Y at a comparison circuit and counters, judging which the line is black, picture or subtitle by inputting the obtained histograms to the comparison circuit, detecting lines varying from black to picture, from picture to black and from subtitle to black at an edge detection circuit and judging if the lines varying from black to picture and from picture to black is stable in time or not at a temporal filter.

EP0675645A2, drawing sheet 1
Sheet 1 of 20

Term

Term ended

Projected expiry passed 21 March 2015, 11.5 years ago.

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20 claims: 10 independent, 10 dependent

  1. 1
    An apparatus for discriminating video kinds comprising:(1) histogram generation means for detecting luminance signal level at every first designated period of an input video signal and for generating histograms expressing frequency (rate of recurrence) distributions for each brightness level;(2) comparison means for classifying the frequency distributions for each brightness level of the output at every second designated period of said histogram generation means as a plurality of video kinds;(3) edge detection means for detecting variation of said video kinds from the output of said comparison means;(4) counter means for generating timing signals for specifying positions of the variation points to different video kinds detected at said edge detection means;and (5) temporal filter means for generating a position signal of the video signal when a time untill the next variation is detected lasts for a designated period after the variation of the video kind at said edge detection means;and    wherein    video kinds of the information included in said onput video signal is discriminated from the output of said temporal filter means.
  2. 2
    An automatic aspect ratio discrimination apparatus comprising:(1) histogram generation means for detecting luminance signal level at every first designated period of an input video signal and for generating histograms expressing frequency distributions for each brightness level;(2) comparison means for classifying the frequency distributions for each brightness level of the output at every second designated period of said histogram generation means as a plurality of video kinds;(3) edge detection means for detecting variation of said video kinds from the output of said comparison means;(4) means for discriminating an aspect ratio of the picture portion of said input video signal from the outputs of said comparison means and said edge detection means.
  3. 5
    An apparatus for discriminating video kinds comprising:(1) histogram generation means for sampling a luminance signal of the onput video signal and for generating histograms expressing frequency distributions for each brightness level at every scanning line;(2) comparison means for onputting the histograms generated at said histogram generation means in order and for classifying said histograms as a video kind;(3) edge detection means for detecting a variation of said input video signal to a video kind with a different scanning line, from the output of said comparison means;(4) counter means for generating a timing signal to specify a position on said input video signal corresponding to the point varying to a different video kind detected at said edge detection means;and (5) temporal filter means for generating a position signal when a time until the next variation is detected lasts for a designated period after the variation of video kind is detected at said edge detection means;and    wherein    a video kind of the information included in said onput video signal from the output of said temporal filter means.
  4. 6
    An automatic aspect ratio discrimination apparatus comprising:(1) histogram generation means for sampling a luminance signal of the onput video signal and for generating histograms expressing frequency distributions for each brightness level at every scanning line;(2) comparison means for onputting the histograms generated at said histogram generation means in order and for classifying said histograms as a video kind;(3) edge detection means for detecting a variation of said input video signal to a video kind with a different scanning line, from the output of said comparison means;(4) means for discriminating an aspect ratio of the picture portion of said input video signal from the outputs of said comparison means and said edge detection means.
  5. 11
    An apparatus for discriminating video kinds comprising:(1) first comparison means    comparing a luminance signal Y and slice levels S and T and    outputting a first output which becomes a level H when said luminance signal Y is smaller than said slice level S (YT);(2) first, second and third counter means counting said first, second and third outputs of said first comparison means, respectively;(3) second comparison means    comparing outputs N1, N2 and N3 of said first, second and third counters, respectively and constants A, B, C and D and    outputting a first output which becomes a level H when said third counter output N1 is larger than said constant A (N1>A),    outputting a third output which becomes a level H when said first counter output N1 is larger than said constant B (N1>B), said second counter output N2 is smaller than said constant C (N2D), and    outputting a second output which becomes a level H when said first and third counter outputs N1 and N3 are both L levels;(4) fourth counter    inputting a horizontal sync signal as a clock input and    counting the horizontal input pulses from zero one by one;(5) edge detection means    inputting the first, second and third outputs CP1, CP2 and CP3 of said second comparison means, respectively and the output of said fourth counter and    outputting a first output m detecting the value of said fourth counter when the output of a second comparison circuit varies from CP1 to CP2,    outputting a second output n detecting the value of said fourth counter when the output of a second comparison circuit varies from CP2 to CP1, and    outputting a third output 1 detecting the value of said fourth counter when the output of a second comparison circuit varies from CP3 to CP1;and (6) temporal filter means    inputting the first and second outputs m and n of said edge detection means as first and second outputs, respectively,    outputting the input values m and n as first and second outputs, respectively, when input values m and n are constant during a period longer than a specified time and    outputting the values m' and n' held in said temporal filter means as first and second outputs, respectively, independent of the input values, in the other cases.
  6. 12
    An automatic aspect ratio discrimination apparatus comprising:(1) first comparison means    comparing a luminance signal Y and slice levels S and T and    outputting a first output which becomes a level H when said luminance signal Y is smaller than said slice level S (YT);(2) first, second and third counter means counting said first, second and third outputs of said first comparison means, respectively;(3) second comparison means    comparing outputs N1, N2 and N3 of said first, second and third counters, respectively and constants A, B, C and D and    outputting a first output which becomes a level H when said third counter output N1 is larger than said constant A (N1>A),    outputting a third output which becomes a level H when said first counter output N1 is larger than said constant B (N1>B), said second counter output N2 is smaller than said constant C (N2D), and    outputting a second output which becomes a level H when said first and third counter outputs N1 and N3, respectively are both L levels;(4) fourth counter    inputting a horizontal sync signal as a clock input and    counting the horizontal input pulses from zero one by one;(5) edge detection means    inputting the first, second and third outputs CP1, CP2 and CP3 of said second comparison means, respectively and the output of said fourth counter and    outputting a first output m detecting the value of said fourth counter when the output of a second comparison circuit varies from CP1 to CP2,    outputting a second output n detecting the value of said fourth counter when the output of a second comparison circuit varies from CP2 to CP1, and    outputting a third output 1 detecting the value of said fourth counter when the output of a second comparison circuit varies from CP3 to CP1;(6) temporal filter means    inputting the first and second outputs m and n of said edge detection means as first and second outputs, respectively,    outputting the input values m and n as first and second outputs, respectively, when input values m and n are constant during a period longer than a specified time and    outputting the values m' and n' held in said temporal filter means as first and second outputs, respectively, independent of the input values, in the other cases;and (7) means for discriminating an aspect ratio of the picture portion of said input video signal from the output of said temporal filter.
  7. 17
    An automatic aspect ratio discrimination apparatus comprising:(1) first comparison means    comparing a luminance signal Y and slice levels S and T and    outputting a first output which becomes a level H when said luminance signal Y is smaller than said slice level S (YT);(2) first, second and third counter means counting said first, second and third outputs of said first comparison means, respectively;(3) second comparison means    comparing outputs N1, N2 and N3 of said first, second and third counters, respectively and constants A, B, C and D and    outputting a first output which becomes a level H when said third counter output N1 is larger than said constant A (N1>A),    outputting a third output which becomes a level H when said first counter output N1 is larger than said constant B (N1>B), said second counter output N2 is smaller than said constant C (N2D), and    outputting a second output which becomes a level H when said first and third counter outputs N1 and N3 are both L levels;(4) vertical filter means    inputting the outputs CP1, CP2 and CP3 of said second comparison means and    outputting the first, second and third outputs CP1', CP2' and CP3', respectively after removing heterogeneous points generated during one field period;(5) fourth counter    inputting a horizontal sync signal as a clock input and a vertical sync signal as a reset input and    counting the horizontal and vertical input pulses from zero one by one;(6) edge detection means    inputting the first, second and third outputs CP1', CP2' and CP3' of said second comparison means, respectively and the output of said fourth counter and    outputting a first output detecting the value of said fourth counter when the output of said vertical filter means varies from CP1' to CP2',    outputting a second output detecting the value of said fourth counter when the output of said vertical filter means varies from CP2' to CP1', and    outputting a third output detecting the value of said fourth counter when the output of said vertical filter means varies from CP3' to CP1';(7) verification means    inputting the first, second and third outputs m, n and 1 of said edge detection means, respectively and specified values a , b , c and d ,    outputting the input values m, n and 1 as first, second and third outputs, respectively, when the values m and n are determined each in one value, m is larger than a and smaller than b ( a R);(10) fifth counter    inputting an output of said third comparison means and inputting a horizontal sync signal as a clock input;(11) fourth comparison means    inputting an output k of said fifth counter and a constant v and    outputting a level H when said output k is larger than said constant v;(12) enable/disable control means    inputting an output m'' of said time filter as a first input and an output of said fourth counter as a second input and    outputting a level H during a period which said fourth counter output varies from zero to m'' and    outputting a level L in the other cases;(13) sixth counter means    inputting an output of said enable/disable control means as a first input,    inputting the first output CP1'of said vertical filter means as a second input, and    inputting a horizontal sync signal as a clock input;(14) sixth comparison means    inputting the output BN of said sixth counter means as a first input, and    inputting a constant Q as a second input, and    outputting a level H when said sixth counter means output BN is larger than said constant Q (BN>Q);and (15) selector means    inputting outputs of said fourth and sixth comparison means as first and second inputs, respectively and a control signal zon, and    outputting a signal SO to said temporal filter means as a fourth input;and (16) means for discriminating an aspect ratio of the picture portion of said input video signal from the output of said temporal filter.
  8. 18
    An automatic aspect ratio discrimination apparatus comprising:(1) first comparison means    comparing a luminance signal Y and slice levels S and T and    outputting a first output which becomes a level H when said luminance signal Y is smaller than said slice level S (Y=S) and said luminance signal Y is not larger than said slice level T (YT);(2) first, second and third counter means counting said first, second and third outputs of said first comparison means, respectively;(3) second comparison means    comparing outputs N1, N2 and N3 of said first, second and third counters, respectively and constants A, B, C and D and    outputting a first output which becomes a level H when said third counter output N1 is larger than said constant A (N1>A),    outputting a third output which becomes a level H when said first counter output N1 is larger than said constant B (N1>B), said second counter output N2 is smaller than said constant C (N2D), and    outputting a second output which becomes a level H when said first and third counter outputs N1 and N3,respaectively are both L levels;(4) vertical filter means    inputting the outputs CP1, CP2 and CP3 of said second comparison means and    outputting the first, second and third outputs CP1', CP2' and CP3', respectively after removing heterogeneous points generated during one field period;(5) fourth counter    inputting a horizontal sync signal as a clock input and a vertical sync signal as a reset input and    counting the horizontal and vertical input pulses from zero one by one;(6) edge detection means    inputting the first, second and third outputs CP1', CP2' and CP3' of said second comparison means, respectively and the output of said fourth counter and    outputting a first output detecting the value of said fourth counter when the output of said vertical filter means varies from CP1' to CP2',    outputting a second output detecting the value of said fourth counter when the output of said vertical filter means varies from CP2' to CP1', and    outputting a third output detecting the value of said fourth counter when the output of said vertical filter means varies from CP3' to CP1';(7) verification means    inputting the first, second and third outputs m, n and 1 of said edge detection means, respectively and specified values a , b , c and d ,    outputting the input values m, n and 1 as first, second and third outputs, respectively, when the values m and n are determined each in one value, m is larger than a and smaller than b ( a Q);and (15) selector means    inputting outputs of said fourth and sixth comparison means as first and second inputs, respectively and a control signal zon, and    outputting a signal SO to said temporal filter means as a fourth input;and (16) means for discriminating an aspect ratio of the picture signal portion of said input video signal from the output of said temporal filter.
  9. 19
    A television receiver comprising:(1) receiving means for inputting an input video signal;(2) first signal processing means for executing demodulation processing of a luminance signal and a chrominance signal of the video signal inputted from said receiving means;(3) second signal processing means for executing secondary signal processing such as picture quality improvement for the signal processed at said first signal processing means;(4) drive means for outputting a drive signal for displaying said video signal information using the signal processed at said second signal processing means;and (5) display means being driven by a drive signal outputted from said drive means and for displaying said video signal information;and    wherein    said first signal processing means comprises (a) histogram generation means detecting luminance signal level at every first specified period of said digital video signal and for generating histograms expressing frequency distribution for each brightness level;(b) comparison means for classifying frequency distribution for each brightness level of the output at every second specified period of said histogram generation means as a plurality of video kinds;(c) edge detection means for detecting variation of said video kind from the output of said comparison means;and (d) means for discriminating an aspect ratio of the picture portion of said input video signal from the outputs of said comparison means and said edge detection means.
  10. 20
    A television receiver comprising:(1) receiving means for inputting an input video signal;(2) first signal processing means for converting an analog video signal inputted from said receiving means to degital video signal and for executing demodulation processing of a luminance signal and a chrominance signal of the video signal inputted from said receiving means;(3) second signal processing means for executing secondary signal processing such as picture quality improvement for the signal processed at said first signal processing means;(4) drive means for outputting a driving signal for displaying said video signal information using an analog signal converted at said second signal processing means;and (5) display means being driven by a drive signal outputted from said drive means and for displaying said video signal information;and    wherein    said first signal processing means comprises (a) histogram generation means detecting luminance signal level at every first specified period of said digital video signal and for generating histograms expressing frequency distribution for each brightness level;(b) comparison means for classifying frequency distribution for each brightness level of the output at every second specified period of said histogram generation means as a plurality of video kinds;(c) edge detection means for detecting variation of said video kind from the output of said comparison means;and (d) means for discriminating an aspect ratio of the picture portion of said input video signal from the outputs of said comparison means and said edge detection means.
Independent claims10