JP2001238185A - Image signal converting apparatus, image signal conversion method, image display device using it, and device and method for generating coefficient data used for it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coefficient data generator that can optionally adjust the resolution of an image of an output image signal. SOLUTION: An image signal conversion section 100 converts an SD signal (525i) into an HD signal (525p or the like) and displays the image on a display section 111. A space class and a motion class are detected from pixel data corresponding to a target pixel of the HD signal selectively extracted from the SD signal to obtain a class code CL denoting a class of the target pixel of the HD signal. When a user selects a resolution, a controller 101 loads coefficient data by each class in the selected resolution into coefficient memory 134 from an information memory bank 135. An arithmetic circuit 127 applies an arithmetic operation to the pixel data of the target pixel of the HD signal by using an estimation equation from data xi of a tap corresponding to the target pixel of the HD signal extracted selectively by the SD signal by a tap selection circuit 121 and coefficient data wi read from the coefficient memory 134 by the class code CL.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
SIGNAL CONVERSION APPARATUS, IMAGE SIGNAL CONVERSION METHOD, AND IMAGE DISPLAY APPARATUS USING THE CONVERSION APPLICATION IN CONVERTING VIDEO SIGNALS TO HIGH-VISION VIDEO SIGNALS About the method. More specifically, when converting the first image signal into the second image signal, the pixel data of the pixel of interest according to the second image signal is generated in accordance with the resolution selected by the user, whereby the second image signal is generated. The present invention relates to an image signal conversion device or the like that enables a user to arbitrarily adjust the resolution of an image based on an image signal to a desired value.

[0002]

2. Description of the Related Art In recent years, with the increase in audio-visual orientation, it has been desired to develop a television receiver capable of obtaining a higher-resolution image. In response to this demand, a so-called Hi-Vision has been developed. The number of scanning lines for Hi-Vision is 1125, which is more than double that of 525 for the NTSC system. In addition, the aspect ratio of Hi-Vision is 9:16, while the aspect ratio of NTSC is 3: 4. For this reason, high-definition images can be displayed with higher resolution and a sense of realism as compared with the NTSC system.

[0003] Hi-Vision has such excellent characteristics, but it is impossible to display an image by the Hi-Vision system even if the video signal of the NTSC system is supplied as it is. This is because the standards differ between the NTSC system and Hi-Vision as described above.

Therefore, in order to display an image corresponding to an NTSC system video signal in a high-vision system, the present applicant has previously proposed a conversion device for converting an NTSC system video signal into a high-vision video signal. (See Japanese Patent Application No. 6-205934). In this converter, NT
From the SC video signal, extract pixel data of a block (region) corresponding to a target pixel related to a Hi-Vision video signal, determine the class of the target pixel based on a level distribution pattern of the pixel data of this block, The pixel data of the target pixel is generated corresponding to this class.

[0005]

In the above-described converter, the resolution of an image based on a high-definition video signal is fixed. Resolution could not be.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an image signal conversion device and the like that enable a user to arbitrarily adjust the resolution of an image based on an output image signal to a desired value.

[0007]

An image signal conversion apparatus according to the present invention is an image signal conversion apparatus for converting a first image signal comprising a plurality of pixel data into a second image signal comprising a plurality of pixel data. , From the first image signal, the second
A plurality of first pixels located around the pixel of interest related to the image signal
First data selecting means for selecting the pixel data of the first pixel data, class detecting means for detecting the class to which the target pixel belongs based on the plurality of first pixel data selected by the first data selecting means, Resolution selecting means for selecting the resolution of an image based on the second image signal, and pixel data generating means for generating pixel data of the pixel of interest corresponding to the class determined by the class detecting means and the resolution selected by the resolution selecting means. Is provided.

For example, the pixel data generating means has a memory for storing coefficient data of an estimation formula generated in advance for each combination of the class detected by the class detecting means and the resolution selected by the resolution selecting means. Coefficient data generating means for generating coefficient data corresponding to the class detected by the detecting means and the resolution selected by the resolution selecting means; and a position from the first image signal around the pixel of interest relating to the second image signal. A second data selecting means for selecting a plurality of second pixel data to be processed; and a plurality of second pixel data selected by the second data selecting means and coefficient data generated by the coefficient data generating means. Calculating means for calculating the pixel data of the pixel of interest using the estimation formula.

The image signal conversion method according to the present invention is the image signal conversion method for converting a first image signal composed of a plurality of pixel data into a second image signal composed of a plurality of pixel data. A first step of selecting, from an image signal, a plurality of first pixel data located around a pixel of interest relating to a second image signal; and a plurality of first pixel data selected in the first step A second step of detecting a class to which the pixel of interest belongs, based on
A third step of selecting a resolution of an image based on the image signal of the second step, and a fourth step of generating pixel data of the pixel of interest corresponding to the class detected in the second step and the resolution selected in the third step. And the following steps.

The image display device according to the present invention has an image signal input section for inputting a first image signal composed of a plurality of pixel data, and a first image signal input from the image signal input section.
Image signal converting means for converting the image signal into a second image signal composed of a plurality of pixel data and outputting the second image signal, and image display means for displaying an image based on the second image signal output from the image signal converting means And resolution selection means for selecting the resolution of an image displayed on the image display means. Then, the image signal converting means selects, from the first image signal, a plurality of first pixel data located around the pixel of interest relating to the second image signal, and a first data selecting means for selecting the first pixel data. Class detecting means for detecting the class to which the pixel of interest belongs based on the plurality of first pixel data selected by the data selecting means, and the class detected by the class detecting means and the resolution selected by the resolution selecting means. And pixel data generating means for generating pixel data of the target pixel.

In the present invention, from the first image signal,
A plurality of first pixel data located around the target pixel related to the second image signal is selected, and a class to which the target pixel belongs is detected based on the plurality of first pixel data. For example, a level distribution pattern of a plurality of first pixel data is detected, and a class to which the target pixel belongs is detected based on the level distribution pattern. The first
Is obtained, for example, from a broadcast signal. Also, by the user pressing the resolution up key and the resolution down key or rotating the resolution adjustment knob,
The resolution based on the second image signal is selected. The resolution thus selected is displayed as a numerical value, a bar graph, or the like on a screen of a display unit, for example, a display unit on which an image based on the second image signal is displayed. The first and second data selection means may be configured in common, so that the plurality of first pixel data and the plurality of second pixel data may be the same.

[0012] Then, pixel data of the image of interest is generated corresponding to the selected resolution and the detected class. For example, coefficient data of an estimation expression generated in advance for each combination of class and resolution is stored in a memory, and coefficient data corresponding to the selected resolution and detected class is read out from the memory, and the first data is read out. A plurality of pieces of second pixel data located around the target pixel related to the second image signal are selected from the image signals of, and the pixel data of the target pixel is calculated by the above estimation formula.

As described above, when converting the first image signal into the second image signal, the pixel data of the target pixel relating to the second image signal is generated in accordance with the resolution selected by the user. Is done. Therefore, the user can arbitrarily adjust the resolution of the image based on the second image signal to a desired value as in the conventional adjustment of contrast and sharpness.

Further, according to the present invention, there is provided a coefficient data generating apparatus for converting a first image signal including a plurality of pixel data into a second image signal including a plurality of pixel data. In an apparatus for generating data, a signal processing means for processing a teacher signal corresponding to a second image signal to obtain an input signal corresponding to the first image signal; Resolution selecting means for selecting a resolution, first data selecting means for selecting a plurality of first pixel data located around a pixel of interest relating to the teacher signal from the input signal, and first data selecting means. Class detection means for detecting a class to which the pixel of interest belongs based on the plurality of pieces of selected first pixel data; and a plurality of first pixels located around the pixel of interest related to the teacher signal from the input signal. A second data selecting means for selecting the pixel data, a class detected by the class detecting means, a plurality of second pixel data selected by the second data selecting means, and a pixel of interest relating to the teacher signal. Thus, for each class, there is provided a normal equation generating means for generating a normal equation for obtaining coefficient data, and a coefficient data calculating means for obtaining the coefficient data for each class by solving the normal equation.

Further, according to the coefficient data generating method of the present invention, the coefficient of the estimation formula used when converting the first image signal composed of a plurality of pixel data into the second image signal composed of a plurality of pixel data. In the method for generating data, a first step of processing a teacher signal corresponding to a second image signal to obtain an input signal corresponding to the first image signal, and a step of processing the input signal obtained in the first step A second step of selecting the resolution of the image, a third step of selecting a plurality of first pixel data located around the pixel of interest related to the teacher signal from the input signal, and a selection of the third step A fourth step of detecting a class to which the pixel of interest belongs based on the plurality of pieces of first pixel data thus obtained; and extracting a plurality of second pixel data located around the pixel of interest related to the teacher signal from the input signal. A fifth step of selecting, 4th
Generating a normal equation for obtaining coefficient data for each class from the class detected in the step, the plurality of second pixel data selected in the fifth step, and the target pixel related to the teacher signal. And a seventh step of solving the normal equation generated in the sixth step to obtain coefficient data for each class.

In the present invention, a second image signal, for example, a teacher signal corresponding to a high definition video signal is processed to obtain an input signal corresponding to a first image signal, for example, an NTSC video signal. In this case, the resolution of the image based on the input signal corresponds to the resolution selected in advance.

From this input signal, a plurality of first pixel data located around the target pixel related to the teacher signal are selected, and the class to which the target pixel belongs is detected based on the plurality of first pixel data. Is done. Further, from the input signal, a plurality of second pixel data located around the target pixel related to the teacher signal is selected.

Then, a normal equation for obtaining coefficient data for each class is generated from the detected class, the plurality of selected second pixel data, and the target pixel relating to the teacher signal, By solving this normal equation, coefficient data for each class can be obtained.

As described above, the first image signal is converted to the second image signal.
The coefficient data of the estimation formula used when converting the image signal into the image signal is generated. As the resolution of the image based on the input signal described above decreases, the resolution of the image based on the second image signal increases. . Thereby, the coefficient data is generated by sequentially changing the resolution of the image based on the input signal, and the coefficient data is selectively used when the first image signal is converted into the second image signal. 2 can arbitrarily adjust the resolution of the image signal.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a configuration of a television receiver 100 as an embodiment. This television receiver 100 converts an SD (Standard) signal from a broadcast signal.
Definition) A 525i signal is obtained as a signal.
25i signals as HD (High Definition) signals
25p signal or 1050i signal, and its 525
The image is displayed by the p signal or the 1050i signal.

Here, the 525i signal has 52 lines.
Five lines mean an interlaced image signal, and 525p
The signal means a progressive (non-interlaced) image signal having 525 lines, and 10
The 50i signal means an interlaced image signal having 1050 lines.

The tele-receiver 100 includes a microcomputer, and has a system controller 101 for controlling the operation of the entire system and a remote control signal receiving circuit 102 for receiving a remote control signal.
The remote control signal receiving circuit 102 is connected to the system controller 101 and outputs a remote control signal RM output from the remote control transmitter 200 in response to a user operation.
Is received, and an operation signal corresponding to the signal RM is supplied to the system controller 101.

The television receiver 100 is supplied with a receiving antenna 105 and a broadcast signal (RF modulated signal) captured by the receiving antenna 105, and performs channel selection processing, intermediate frequency amplification processing, detection processing, and the like. SD signal Va described above
(525i signal) and an external S
External input terminal 1 for inputting D signal Vb (525i signal)
07, a changeover switch 108 for selectively outputting one of these SD signals Va and Vb, and a changeover switch 1
And a buffer memory 109 for temporarily storing the SD signal output from the device 08.

The SD signal V output from the tuner 106
a is supplied to the fixed terminal on the a side of the changeover switch 108,
The SD signal Vb input from the external input terminal 107 is supplied to a fixed terminal on the b side of the changeover switch 108. The switching operation of the changeover switch 108 is controlled by the system controller 101.

Further, the television receiver 100 includes an image signal converter 110 for converting an SD signal (525i signal) temporarily stored in the buffer memory 109 into an HD signal (525p signal or 1050i signal), A display unit 111 for displaying an image based on the HD signal output from the signal conversion unit 110;
A display signal S for displaying a character graphic or the like on the screen 1
OSD (On Screen Display) for generating CH
It has a circuit 112 and a combiner 113 for combining the display signal SCH with the HD signal output from the image signal converter 110 and supplying the HD signal to the display unit 111.

The display unit 111 is, for example, a CRT
(Cathode-ray tube) display or LCD (l
It is composed of a flat panel display such as an iquid crystal display. The operation of generating the display signal SCH in the OSD circuit 112 is controlled by the system controller 101.

The operation of the television receiver 100 shown in FIG. 1 will be described.

When a mode for displaying an image corresponding to the SD signal Va output from the tuner 106 is selected by the user's operation of the remote control transmitter 200, the changeover switch 108 is connected to the a side under the control of the system controller 101. The changeover switch 108 sets the SD signal V
a is output. On the other hand, the user's remote control transmitter 200
The SD signal Vb input to the external input terminal 107 by the operation
Is selected, the changeover switch 108 is connected to the b side under the control of the system controller 101, and the SD signal Vb is output from the changeover switch 108.

The SD signal (525i signal) output from the changeover switch 108 is stored in the buffer memory 109 and is temporarily stored. And this buffer memory 1
09 is temporarily stored in the image signal conversion unit 1.
10 and the HD signal (525p signal or 105
0i signal). That is, the image signal conversion unit 1
In FIG. 10, the pixel data (hereinafter referred to as “S
D pixel data "), pixel data constituting the HD signal (hereinafter, referred to as" HD pixel data ") is obtained. Here, the selection of the 525p signal or the 1050i signal is performed by the user operating the remote control transmitter 200. The HD signal output from the image signal conversion unit 110 is supplied to the display unit 111 via the synthesizer 113, and an image based on the HD signal is displayed on the screen of the display unit 111.

In addition, the user can select the resolution of the image displayed on the screen of the display unit 111 by operating the remote control transmitter 200, as described above. For example, in the resolution selection mode, the resolution is selected by pressing the up key and the down key. Further, for example, in the resolution selection mode, the resolution is selected by rotating a knob such as a jog dial.

In the image signal converter 110, HD pixel data is calculated by an estimation formula, as described later. The coefficient data of the estimation formula corresponds to the resolution selected by the user's operation of the remote control transmitter 200. Is used. Thus, the resolution of the image based on the HD signal output from the image signal conversion unit 110 corresponds to the selected resolution.

In the state where the resolution selection operation is performed by the user's operation of the remote control transmitter 200,
The selected resolution is displayed on the screen of the display unit 111. Although not shown, this display is displayed as a numerical value or a bar graph. The user can select a resolution by referring to the resolution display. When displaying the selected resolution on the screen in this manner, the system controller 101 supplies display data to the OSD circuit 112. Thereby, the OSD circuit 112 generates a display signal SCH based on the display data, and generates the display signal SCH.
The CH is supplied to the display unit 111 via the synthesizer 113.

Next, the details of the image signal converter 110 will be described. The image signal conversion unit 110 includes a buffer memory 1
09 from the SD signal (525i signal) stored in
There are first to third tap selection circuits 121 to 123 for selectively extracting and outputting data of a plurality of SD pixels located around the target pixel related to the HD signal (1050i signal or 525p signal).

The first tap selection circuit 121 selectively extracts data of SD pixels (referred to as "prediction taps") used for prediction. Second tap selection circuit 1
Reference numeral 22 is for selectively extracting data of SD pixels (referred to as “space class taps”) used for class classification corresponding to the level distribution pattern of the SD pixel data. The third tap selection circuit 123 selectively extracts data of SD pixels (referred to as “motion class taps”) used for class classification corresponding to motion. When a space class is determined using SD pixel data belonging to a plurality of fields, the space class also includes motion information.

FIG. 2 shows a pixel positional relationship between the 525i signal and the 525p signal in an odd (o) field of a certain frame (F). Large dots are pixels of the 525i signal, and small dots are pixels of the 525p signal to be output. In the even (e) field, the line of the 525i signal is spatially shifted by 0.5 line. As can be seen from FIG. 2, the pixel data of the 525p signal includes line data L at the same position as the line of the 525i signal.
1 and line data L2 at an intermediate position between the upper and lower lines of the 525i signal. The number of pixels in each line of the 525p signal is twice the number of pixels in each line of the 525i signal.

FIG. 3 shows the pixel position relationship of a certain frame (F) with the 525i signal and the 1050i signal. The pixel position of the odd (o) field is indicated by a solid line, and the pixel position of the even (e) field is indicated by a solid line. This is indicated by a broken line. A large dot is a pixel of the 525i signal, and a small dot is a pixel of the 1050i signal to be output. As can be seen from FIG. 3, the pixel data of the 1050i signal is 5
Line data L1, L at positions near the line of the 25i signal
1 'and line data L2, L2' located far from the line of the 525i signal. Here, L1 and L2 are line data of odd fields, and L1 'and L2' are line data of even fields. The number of pixels in each line of the 1050i signal is twice as many as the number of pixels in each line of the 525i signal.

FIG. 4 and FIG.
When converting to a 5p signal, the first tap selection circuit 12
1 shows a specific example of a prediction tap (SD pixel) selected at 1. FIGS. 4 and 5 show vertical pixel positional relationships of odd (o) and even (e) fields of temporally continuous frames F-1, F, and F + 1.

As shown in FIG. 4, the prediction taps for predicting the line data L1 and L2 of the field F / o are:
The SD which is included in the next field F / e and spatially adjacent to the pixel of the 525p signal to be created (pixel of interest)
Pixels T1, T2, T3 and included in field F / o,
SD pixels T4, T5, T6 spatially adjacent to the 525p signal pixel to be created, and the previous field F-1
/ E, the SD pixels T7, T8, T9 spatially adjacent to the pixel of the 525p signal to be created, and the pixels of the 525p signal to be created, included in the preceding F-1 / o. Is an SD pixel T10 at a spatially neighboring position with respect to.

As shown in FIG. 5, the prediction taps for predicting the line data L1 and L2 of the field F / e are:
525p to be created, included in the next field F + 1 / o
SD pixel T1, spatially adjacent to the pixel of the signal
T2, T3, and SD pixels T4, T5, and T6 that are included in the field F / e and spatially adjacent to the pixel of the 525p signal to be created, and are included in the previous field F / o and created. The SD pixels T7, T8, T9 spatially adjacent to the pixel of the power 525p signal and the F-1
/ E, which is an SD pixel T10 spatially adjacent to the pixel of the 525p signal to be created.

When the line data L1 is predicted, the SD pixel T9 is not selected as a prediction tap.
On the other hand, when predicting the line data L2, the SD pixel T4 may not be selected as the prediction tap.

FIG. 6 and FIG.
When converting to a 50i signal, the first tap selection circuit 1
21 shows a specific example of a prediction tap (SD pixel) selected at 21. FIGS. 6 and 7 show vertical pixel positional relationships in odd (o) and even (e) fields of temporally continuous frames F-1, F, and F + 1.

As shown in FIG. 6, the prediction taps for predicting the line data L1 and L2 of the field F / o are:
1050i included in the next field F / e and to be created
S spatially adjacent to the pixel of the signal (pixel of interest)
D pixels T1 and T2, SD pixels T3, T4, T5, and T6 included in the field F / o and spatially adjacent to the pixel of the 525p signal to be created;
These are SD pixels T7 and T8 that are included in -1 / e and spatially adjacent to the pixel of the 1050i signal to be created.

As shown in FIG. 7, the prediction taps for predicting the line data L1 'and L2' of the field F / e are included in the next field F + 1 / o and must be created.
The SD pixels T1 and T2 spatially adjacent to the pixel of the 50ip signal and the S pixels S10 included in the field F / e and spatially adjacent to the pixel of the 1050i signal to be created.
D pixels T3, T4, T5, T6 and the previous field F /
The SD pixels T7 and T8 included in o and spatially adjacent to the pixel of the 525p signal to be created.

When predicting the line data L1 and L1 ', the SD pixel T6 is not selected as a prediction tap. On the other hand, when predicting the line data L2 and L2', the SD pixel T3 is selected as a prediction tap. It may not be done.

Further, as shown in FIGS. 4 to 7, one or more SD pixels in the horizontal direction may be selected as prediction taps in addition to SD pixels at the same position in a plurality of fields.

FIG. 8 and FIG.
When converting to a 5p signal, the second tap selection circuit 12
2 shows a specific example of a space class tap (SD pixel) selected in 2. FIG. 8 and FIG. 9 show vertical pixel positional relationships of odd (o) and even (e) fields of temporally continuous frames F-1, F, and F + 1.

As shown in FIG. 8, the space class tap for predicting the line data L1 and L2 of the field F / o is included in the next field F / e and should be created 52.
SD pixels T1 and T2 spatially adjacent to the pixel (target pixel) of the 5p signal and included in field F / o,
The SD pixels T3, T4, T5 spatially adjacent to the pixel of the 525p signal to be created and the previous field F-1
/ E, which are SD pixels T6 and T7 spatially adjacent to the pixel of the 525p signal to be created.

As shown in FIG. 9, the space class tap for predicting the line data L1 and L2 of the field F / e is included in the next field F + 1 / o and should be created.
SD pixels T1 and T2 spatially adjacent to the pixel of the 25p signal and SD pixels T3 and T4 included in the field F / e and spatially adjacent to the pixel of the 525p signal to be created. T5 and T6, and SD pixels T6 and T7 included in the previous field F / o and spatially adjacent to the pixel of the 525p signal to be created.

It should be noted that the SD pixel T7 is not selected as a space class tap when predicting the line data L1, while the SD pixel T6 is not selected as a space class tap when predicting the line data L2. Is also good.

FIGS. 10 and 11 show specific examples of space class taps (SD pixels) selected by the second tap selection circuit 122 when converting a 525i signal to a 1050i signal. FIG. 10 and FIG. 11 show the vertical pixel positions of the odd (o) and even (e) fields of temporally continuous frames F-1, F and F + 1.

As shown in FIG. 10, the space class tap for predicting the line data L1 and L2 of the field F / o is included in the field F / o and should be created 105
The SD pixels T1, T2, T3 spatially adjacent to the pixel of the 0i signal (pixel of interest) and the previous field F-1 /
e, SD pixels T4, T5, T6, and T7 spatially adjacent to the pixel of the 1050i signal to be created.

As shown in FIG. 11, the space class tap for predicting the line data L1 'and L2' of the field F / e is included in the field F / e, and is to be created.
SD pixels T1, T2 and T3 spatially adjacent to the pixel of the 050i signal and SD pixels included in the previous field F / o and spatially adjacent to the pixel of the 1050i signal to be created T4, T5, T6, and T7.

When predicting the line data L1 and L1 ', the SD pixel T7 should not be selected as a space class tap. On the other hand, when predicting the line data L2 and L2', the SD pixel T4 should be selected as a space class tap. May not be selected.

Further, as shown in FIGS. 8 to 11, one or more SD pixels in the horizontal direction may be selected as space class taps in addition to SD pixels at the same position in a plurality of fields.

FIG. 12 shows a specific example of a motion class tap (SD pixel) selected by the third tap selection circuit 123 when converting a 525i signal to a 525p signal. FIG. 12 shows a vertical pixel positional relationship between odd-numbered (o) and even-numbered (e) fields of temporally continuous frames F-1 and F. As shown in FIG. 12, the motion class tap for predicting the line data L1 and L2 of the field F / o is included in the next field F / e and corresponds to the pixel of the 525p signal to be created (pixel of interest). SD pixels n2, n4, and n6 spatially adjacent to each other, and SD pixels n1, n3, and n5 spatially adjacent to the pixel of the 525p signal to be created and included in the field F / o.
525p to be created, included in the previous field F-1 / e
SD pixel m2, spatially adjacent to the pixel of the signal
m4, m6, and SD pixels m1, m3, and m5 included in the previous field F-1 / o and spatially adjacent to the pixel of the 525p signal to be created. SD pixel n
The vertical position of each of 1 to n6 is the SD pixel m1
The vertical positions of m6 coincide with each other.

FIG. 13 shows a specific example of a motion class tap (SD pixel) selected by the third tap selection circuit 123 when converting a 525i signal to a 1050i signal. FIG. 13 shows frames F-1, F that are temporally continuous.
Of the odd (o) and even (e) fields of FIG. As shown in FIG. 13, the motion class tap for predicting the line data L1 and L2 of the field F / o is included in the next field F / e.
The SD pixels n2, n4, and n6 spatially adjacent to the pixel of the 1050i signal to be created and the field F / o
And the SD pixels n1, n3, and n5 spatially adjacent to the pixel of the 1050i signal to be created and the pixels of the 1050i signal to be created included in the previous field F-1 / e. And the spatially neighboring SD pixels m2 and m
4, m6 and included in the previous field F-1 / o,
The SD pixels m1, m3, and m5 are spatially close to the pixel of the 1050i signal to be created. SD pixel n1
To n6 in the vertical direction are SD pixels m1 to m6, respectively.
The respective vertical positions of m6 coincide.

Returning to FIG. 1, the image signal converter 11
0 indicates a level distribution pattern of space class tap data (SD pixel data) selectively extracted by the second tap selection circuit 122, detects a space class based on the level distribution pattern, and obtains class information. Is output.

In the space class detection circuit 124, for example,
An operation for compressing each SD pixel data from 8-bit data to 2-bit data is performed. Then, from the space class detection circuit 124, compressed data corresponding to each SD pixel data is output as space class information. In the present embodiment, ADRC (Adaptive Dyn
Data compression is performed by amic range coding. As information compression means, other than ADRC, DP
CM (prediction coding), VQ (vector quantization), or the like may be used.

Originally, ADRC is a VTR (Video Tape R)
ecorder) is an adaptive requantization method developed for high-performance coding. However, since local patterns at the signal level can be efficiently expressed with a short word length, it is suitable for use in the data compression described above. Things. When using ADRC, the maximum value of the space class tap data (SD pixel data) is MAX, the minimum value is MIN, and the dynamic range of the space class tap data is DR (= MAX-MIN +
1) Assuming that the number of requantization bits is P, for each SD pixel data ki as data of a space class tap,
By the operation of the expression (1), a requantized code Qi as compressed data is obtained. However, in equation (1), []
Means truncation processing. When there are Na SD pixel data as space class tap data, i =
1 to Na.

Qi = [(ki−MIN + 0.5). 2 ^P / DR] (1) Further, the image signal conversion unit 110 mainly determines the degree of motion from the data (SD pixel data) of the motion class tap selectively extracted by the third tap selection circuit 123. Has a motion class detection circuit 125 which detects a motion class for representing the class and outputs the class information.

In the motion class detection circuit 125, the third
, A difference between frames is calculated from the motion class tap data (SD pixel data) mi and ni selectively extracted by the tap selection circuit 123, and threshold processing is performed on the average value of the absolute values of the differences. Then, a motion class, which is an index of the motion, is detected. That is, in the motion class detection circuit 125, the average value AV of the absolute value of the difference is calculated by Expression (2). Third tap selection circuit 123
Thus, for example, as described above, the 12 SD pixel data m1
When 〜m6, n1 to n6 are extracted, Nb in equation (2) is 6.

[0062]

(Equation 1)

Then, in the motion class detection circuit 125,
The average value AV calculated as described above is compared with one or a plurality of threshold values, and class information MV of the motion class is obtained.
Is obtained. For example, three thresholds th1, th2,
th3 (th1 <th2 <th3) is prepared, and when detecting four motion classes, MV when AV ≦ th1
= 0, th1 <AV ≦ th2, MV = 1, th2
MV = 2 when <AV ≦ th3, and MV = 3 when th3 <AV.

Further, the image signal converter 110 converts the requantization code Qi as the class information of the space class output from the space class detector 124 and the class information MV of the motion class output from the motion class detector 125. Based on the HD signal (525p signal or 105
It has a class synthesis circuit 126 for obtaining a class code CL indicating the class to which the pixel (signal of interest 0i) belongs.

In the class synthesizing circuit 126, the calculation of the class code CL is performed by the equation (3). In addition,
In Equation (3), Na indicates the number of data (SD pixel data) of the space class tap, and P indicates the number of requantization bits in ADRC.

[0066]

(Equation 2)

The image signal conversion unit 110 has registers 130 to 133 and a coefficient memory 134.
The line-sequential conversion circuit 128 described later needs to switch its operation between outputting a 525p signal and outputting a 1050i signal. The register 130 stores operation specifying information for specifying the operation of the line sequential conversion circuit 128. The line-sequential conversion circuit 128 includes the register 1
The operation is performed according to the operation designation information supplied from 30.

The register 131 stores tap position information of a prediction tap selected by the first tap selection circuit 121. The first tap selection circuit 121 selects a prediction tap according to the tap position information supplied from the register 131. The tap position information is for, for example, numbering a plurality of SD pixels that may be selected and designating the number of the SD pixel to be selected. The same applies to the following tap position information.

The register 132 stores tap position information of the space class tap selected by the second tap selection circuit 122. Second tap selection circuit 122
Selects a space class tap according to the tap position information supplied from the register 132.

Here, the register 132 stores tap position information A when the movement is relatively small and tap position information B when the movement is relatively large. Either of the tap position information A and B is assigned to the second tap selection circuit 12.
2 is selected by the motion class information MV output from the motion class detection circuit 125.

That is, when there is no motion or the motion is small and MV = 0 or MV = 1, the tap position information A is supplied to the second tap selection circuit 122 and the second tap selection circuit 122 The space class tap selected by the circuit 122 extends over two fields as shown in FIGS. When MV = 2 or MV = 3 because the motion is relatively large, the tap position information B is supplied to the second tap selection circuit 122, and the space selected by the second tap selection circuit 122 is selected. Although not shown, the class tap is only an SD pixel in the same field as a pixel to be created.

The register 131 stores the tap position information when the movement is relatively small and the tap position information when the movement is relatively large.
May be selected based on the motion class information MV output from the motion class detection circuit 125.

The register 133 stores the tap position information of the motion class tap selected by the third tap selection circuit 123. Third tap selection circuit 123
Selects a motion class tap according to the tap position information supplied from the register 133.

Further, the coefficient memory 134 stores coefficient data of an estimation formula used in the estimation prediction operation circuit 127 described later for each class. The coefficient data is information for converting a 525i signal as an SD signal into a 525p signal or a 1050i signal as an HD signal. The class memory CL supplied from the class synthesizing circuit 126 is supplied as read address information to the coefficient memory 134, and coefficient data corresponding to the class code CL is read from the coefficient memory 134, and the estimated prediction operation circuit 127 Will be supplied.

The image signal conversion section 110 has an information memory bank 135. This information memory bank 1
In 35, operation designation information to be stored in the register 130, tap position information to be stored in the registers 131 to 133, and coefficient data to be stored in the coefficient memory 134 are stored in advance.

Here, as the operation designation information to be stored in the register 130, the information memory bank 135 includes first operation designation information for operating the line sequential conversion circuit 128 to output the 525p signal, Second operation designation information for operating the line-sequential conversion circuit 128 to output the 1050i signal is stored in advance.

By operating the remote control transmitter 200, the user can select a first conversion method for outputting a 525p signal as an HD signal or a second conversion method for outputting a 1050i signal as an HD signal. Information memory bank 1
Selection information of the conversion method is supplied to the system controller 101 from the system controller 101, and the first operation designation information or the second operation designation information is loaded from the information memory bank 135 to the register 130 according to the selection information.

Further, as the tap position information of the prediction tap to be stored in the register 131, the first conversion method (5
25p) and second tap position information corresponding to the second conversion method (1050i) are stored in advance. This information memory bank 135
The first tap position information or the second tap position information is loaded into the register 131 in accordance with the above-described conversion method selection information.

The tap position information of the space class tap to be stored in the register 132 corresponds to the first tap position information corresponding to the first conversion method (525p) and the second conversion method (1050i). And second tap position information to be stored are stored in advance. Note that the first and second
Are composed of tap position information when the movement is relatively small and tap position information when the movement is relatively large. This information memory bank 13
5, the first tap position information or the second tap position information is loaded into the register 132 in accordance with the above-described conversion method selection information.

Further, the tap position information of the motion class tap to be stored in the register 133 corresponds to the first tap position information corresponding to the first conversion method (525p) and the second conversion method (1050i). And second tap position information to be stored are stored in advance. The information memory bank 135 loads the register 133 with the first tap position information or the second tap position information in accordance with the above-described conversion method selection information.

As coefficient data to be stored in the coefficient memory 134, coefficient data for each class at a plurality of resolutions corresponding to each of the first and second conversion methods is stored in advance. A method of generating coefficient data corresponding to the plurality of resolutions will be described later.

Even if not described above, the user can use the remote control transmitter 2
By pressing an up key and a down key or rotating a knob such as a jog dial in the operation unit 00, the resolution of an image based on the HD signal output from the image conversion unit 110 can be arbitrarily selected. The information memory bank 135 is supplied with selection information of the resolution from the system controller 101, and the information memory bank 13
5, the coefficient memory 134 is loaded with coefficient data corresponding to the selected resolution and the selected conversion method described above.

The image signal conversion unit 110 further includes prediction tap data (SD pixel data) xi selectively extracted by the first tap selection circuit 121 and a coefficient memory 134.
H to be created from the coefficient data wi read from
D signal pixel (target pixel) data (HD pixel data)
Is calculated.

In the estimation / prediction calculation circuit 127, 525
When outputting the p signal, as shown in FIG. 2 described above, the odd (o) field and the even (e) field
Line data L1 at the same position as the line of the 25i signal;
It is necessary to generate line data L2 at the intermediate position between the upper and lower lines of the 525i signal and to double the number of pixels in each line. Also, in this estimation operation circuit 127, 105
When outputting the 0i signal, as shown in FIG.
In the odd (o) and even (e) fields,
The line data L1 at a position close to the line of the 525i signal
It is necessary to generate L1 'and line data L2 and L2' located far from the line of the 525i signal, and to double the number of pixels in each line.

Therefore, in the estimation / prediction calculation circuit 127, H
Data of four pixels constituting the D signal are simultaneously generated. For example, the data of the four pixels are simultaneously generated using estimation equations having different coefficient data, and the coefficient memory 134 supplies coefficient data of each estimation equation. Here, in the estimation prediction operation circuit 127, the HD pixel data to be created is obtained from the prediction tap data (SD pixel data) xi and the coefficient data wi read from the coefficient memory 134 by the linear estimation expression of the expression (4). y is calculated. First tap selection circuit 121
When the number of prediction taps selected by is 10 as shown in FIGS. 4 and 5, n in equation (4) is 10.

[0086]

(Equation 3)

The image signal conversion section 110 performs line double speed processing for doubling the horizontal period, and outputs the line data L 1, L 2 (L
1 ′, L2 ′) is line-sequentially converted.

FIG. 14 shows the line double speed processing when outputting a 525p signal by using an analog waveform. As described above, the line data L1 and L2 are generated by the estimation prediction operation circuit 127. Line data L
1 includes lines a1, a2, a3,... In order, and b1, b2, b3,.
・ Lines are included. The line-sequential conversion circuit 128 compresses the data of each line by に in the time axis direction and alternately selects the compressed data, thereby providing a line-sequential output a
0, b0, a1, b1,...

When outputting the 1050i signal, the line-sequential conversion circuit 128 generates a line-sequential output so as to satisfy the interlace relationship in the odd field and the even field. Therefore, the line sequential conversion circuit 128
It is necessary to switch the operation between the case of outputting a 525p signal and the case of outputting a 1050i signal.
The operation specifying information is supplied from the register 130 as described above.

Next, the operation of the image signal converter 110 will be described.

S stored in the buffer memory 109
From the D signal (525i signal), the second tap selection circuit 1
At 22, the data of the space class tap (SD pixel data)
Are selectively taken out. In this case, the second tap selection circuit 122 performs tapping based on the conversion method selected by the user supplied from the register 132 and tap position information corresponding to the motion class detected by the motion class detection circuit 125. Is selected.

The space class tap data (SD pixel data) selectively extracted by the second tap selection circuit 122 is supplied to a space class detection circuit 124. In this space class detection circuit 124, each SD pixel data as the data of the space class tap is subjected to ADRC processing, and is regenerated as class information of a space class (mainly a class classification for representing a waveform in space). The quantization code Qi is obtained (see equation (1)).

The third tap selection circuit 123 selectively extracts motion class tap data (SD pixel data) from the SD signal (525i signal) stored in the buffer memory 109. In this case, the third tap selection circuit 123 selects a tap based on tap position information supplied from the register 133 and corresponding to the conversion method selected by the user.

The data (SD pixel data) of the motion class tap selectively extracted by the third tap selection circuit 123 is supplied to the motion class detection circuit 125. The motion class detection circuit 125 obtains class information MV of a motion class (mainly a class classification for representing a degree of motion) from each SD pixel data as motion class tap data.

The motion information MV and the above-described requantized code Qi are supplied to the class synthesis circuit 126. The class synthesizing circuit 126 obtains a class code CL indicating the class to which the pixel (target pixel) of the HD signal (525p signal or 1050i signal) to be created belongs from the motion information MV and the requantized code Qi ( (See equation (3)). The class code CL is stored in the coefficient memory 13
4 is supplied as read address information.

In the coefficient memory 134, coefficient data for each class in the resolution and conversion method selected by the user are loaded from the information memory bank 135 and stored. As described above, by supplying the class code CL as the read address information, the coefficient data wi corresponding to the class code CL is read from the coefficient memory 134 and supplied to the estimation prediction operation circuit 127.

Further, based on the SD signal (525i signal) stored in the buffer memory 109, the first tap selection circuit 121 uses the prediction tap data (SD pixel data).
Are selectively taken out. In this case, the first tap selection circuit 121 selects a tap based on tap position information supplied from the register 131 and corresponding to the conversion method selected by the user. The prediction tap data (SD pixel data) xi selectively extracted by the first tap selection circuit 121 is calculated by the estimated prediction operation circuit 1
27.

In the estimation prediction operation circuit 127, the data (SD pixel data) xi of the prediction tap and the coefficient memory 134
H to be created from the coefficient data wi read from
D signal pixel (target pixel) data (HD pixel data)
y is calculated (see equation (4)). In this case, data of four pixels constituting the HD signal is simultaneously generated.

Thus, the first 525p signal is output.
Is selected, line data L1 at the same position as the line of the 525i signal and line data L2 at the intermediate position between the upper and lower lines of the 525i signal in the odd (o) field and the even (e) field. Is generated (see FIG. 2). When the second conversion method for outputting the 1050i signal is selected, the line data L1 and L1 'at positions close to the line of the 525i signal in the odd (o) field and the even (e) field, and 52
Line data L2 and L at positions far from the 5i signal line
2 'are generated (see FIG. 3).

The line data L1 and L2 (L1 ', L2') generated by the estimation / prediction operation circuit 127 are supplied to the line-sequential conversion circuit 128. In the line sequential conversion circuit 128, the line data L1, L2 (L
1 ′, L2 ′) are line-sequentially generated to generate an HD signal. In this case, the line-sequential conversion circuit 128
The operation is performed according to the operation instruction information supplied from 0 and corresponding to the conversion method selected by the user. Therefore, when the first conversion method (525p) is selected by the user, the line-sequential conversion circuit 128 outputs
A signal is output. On the other hand, when the second conversion method (1050i) is selected by the user, the line-sequential conversion circuit 128 outputs a 1050i signal.

As described above, the coefficient data of each class stored in the coefficient memory 134 corresponds to the resolution selected by the user. Therefore, when the user performs an operation of changing the resolution with the remote control transmitter 200, the coefficient data of each class stored in the coefficient memory 134 is also changed accordingly, and the pixel data of the HD signal is Is generated according to the resolution selected. Accordingly, the resolution of the image based on the HD signal output from the line-sequential conversion circuit 128 is also changed, and the user can change the resolution of the image based on the HD signal obtained by the conversion as in the conventional adjustment of contrast and sharpness. , Can be arbitrarily adjusted to a desired value.

As described above, the information memory bank 135
Stores coefficient data for each class at a plurality of resolutions. The coefficient data is generated in advance by learning.

First, the learning method will be described.
The coefficient data wi (i = 1 to 1) based on the estimation expression of the expression (4)
Here, an example is shown in which n) is obtained by the least square method. As a generalized example, X is input data, W is coefficient data,
Consider the observation equation (5) with Y as the predicted value. In the equation (5), m indicates the number of learning data, and n indicates the number of prediction taps.

[0104]

(Equation 4)

The least squares method is applied to the data collected by the observation equation (5). Based on the observation equation (5), the residual equation (6) is considered.

[0106]

(Equation 5)

From the residual equation of the equation (6), it is considered that the most probable value of each wi is a case where the condition for minimizing e ² in the equation (7) is satisfied. That is, the condition of equation (8) may be considered.

[0108]

(Equation 6)

That is, n conditions based on i in equation (8) are considered, and w ₁ , w ₂ ,..., W _n satisfying these conditions may be calculated. Then, from the residual equation of equation (6), (9)
An expression is obtained. Further, from equations (9) and (5),
Equation (10) is obtained.

[0110]

(Equation 7)

Then, from equations (6) and (10),
The normal equation of the equation (11) is obtained.

[0112]

(Equation 8)

The normal equation of the equation (11) is expressed by the number n of unknowns.
Since it is possible to make the same number of equations as
The most probable value of i can be obtained. In this case, the simultaneous equations are solved using a sweeping-out method (Guss-Jordan elimination method) or the like.

FIG. 15 shows a learning flow of the coefficient data described above. In order to perform learning, an input signal and a teacher signal to be predicted are prepared.

First, in step ST11, a combination of target pixel data obtained from a teacher signal and n pixel data of prediction taps obtained from an input signal is generated as learning data. Next, in step ST12, it is determined whether or not the generation of the learning data has been completed. If the generation of the learning data has not been completed, in step ST13, the class to which the pixel data of interest in the learning data belongs is determined. The determination of the class is performed based on a predetermined number of pixel data obtained from the input signal corresponding to the target pixel data.

In step ST14, for each class, the learning data generated in step ST11, that is, the target pixel data and the n pixel data of the prediction taps are used to obtain the equation (11). Generate a normal equation. The operations in steps ST11 to ST14 are repeated until the generation of the learning data ends, and a normal equation in which a large amount of learning data is registered is generated.

When the generation of the learning data is completed in step ST12, in step ST15, the normal equation generated for each class is solved to obtain n coefficient data wi for each class. Then, in step ST16, the coefficient data wi is registered in the memory divided into addresses by class, and the learning flow ends.

Next, the coefficient data wi for each class at a plurality of resolutions stored in the information memory bank 135 in the image signal converter 110 of the television receiver 100 shown in FIG. Details of the coefficient data generation device 150 generated in advance will be described. FIG. 16 shows a configuration example of the coefficient data generation device 150.

The coefficient data generating device 150 outputs an HD signal (525p signal / 1050i signal) as a teacher signal.
And a two-dimensional thinning filter 152 that performs horizontal and vertical thinning filter processing on the HD signal to obtain an SD signal as an input signal.
And

A conversion method selection signal is supplied to the two-dimensional thinning filter 152 as a control signal. The first conversion method (5 from the 525i signal by the image signal conversion unit 110 in FIG. 1)
When “obtain 25p signal” is selected, the two-dimensional decimation filter 152 performs a decimation process on the 525p signal to generate an SD signal (see FIG. 2). On the other hand, the second
(The 1050i signal is obtained from the 525i signal by the image signal conversion unit 110 in FIG. 1) is selected, the two-dimensional decimation filter 152 performs a thinning process on the 1050i signal to generate an SD signal. (See FIG. 3).

Further, the two-dimensional thinning filter 152 includes:
A resolution selection signal is supplied as a control signal. This resolution has the same meaning as the resolution that the user can select by operating the remote control transmitter 200 in the television receiver 100 shown in FIG. The higher the resolution indicated by the resolution selection signal, the lower the resolution of the image based on the SD signal generated by the two-dimensional thinning filter 152.

For example, the two-dimensional thinning filter 152 is configured using a Gaussian filter. In this case, HD
The pixel data in the vertical direction forming the signal is thinned out by the one-dimensional Gaussian filter expressed by the equation (12), and the pixel data in the horizontal direction making up the HD signal is similarly thinned out by the same one-dimensional Gaussian filter. Thus, an SD signal is generated. When the two-dimensional decimation filter 152 is configured using a Gaussian filter as described above, the standard deviation σ is determined by the above-described resolution selection signal.
Is changed.

[0123]

(Equation 9)

The coefficient data generating device 150 outputs the SD signal (52) output from the two-dimensional thinning filter 152.
5i signal), the HD signal (1050i signal or 52
5p signal), a plurality of SDs located around the pixel of interest
1st to 3rd for selectively extracting and outputting pixel data
Tap selection circuits 153 to 155.

These first to third tap selection circuits 153
To 155 have the same configuration as the first to third tap selection circuits 121 to 123 of the image signal conversion unit 110 described above. These first to third tap selection circuits 153 to 155
Is selected by tap position information from the tap selection control unit 156.

The tap selection control circuit 156 is supplied with a conversion method selection signal as a control signal. Tap position information supplied to the first to third tap selection circuits 153 to 155 is different between a case where the first conversion method is selected and a case where the second conversion method is selected. . The tap selection control circuit 156 is supplied with the motion class information MV output from the motion class detection circuit 158 described later. Thereby, the tap position information supplied to the second tap selection circuit 154 is made different depending on whether the movement is large or small.

Further, the coefficient data generation device 150
, A level distribution pattern of the data (SD pixel data) of the space class taps selectively extracted by the tap selection circuit 154, a space class is detected based on this level distribution pattern, and the space class for outputting the class information is output. It has a detection circuit 157. The space class detection circuit 157 has the same configuration as the space class detection circuit 124 of the image signal conversion unit 110 described above. From this space class detection circuit 157, a requantization code Qi for each SD pixel data as space class tap data is output as class information indicating a space class.

Further, the coefficient data generating device 150
The motion class detection circuit 158 detects a motion class mainly representing the degree of motion from the data (SD pixel data) of the motion class taps selectively extracted by the tap selection circuit 155, and outputs the class information MV. have. The motion class detection circuit 158 has the same configuration as the motion class detection circuit 125 of the image signal conversion unit 110 described above. In the motion class detection circuit 158, an inter-frame difference is calculated from the data (SD pixel data) of the motion class tap selectively extracted by the third tap selection circuit 155, and the average of the absolute values of the differences is calculated. Then, a threshold value process is performed to detect a motion class that is a motion index.

Further, the coefficient data generation device 150 includes a re-quantization code Qi as the class information of the space class output from the space class detection circuit 157, and the class information MV of the motion class output from the motion class detection circuit 158.
And a class synthesizing circuit 159 for obtaining a class code CL indicating the class to which the pixel of interest relating to the HD signal (525p signal or 1050i signal) belongs.
This class synthesizing circuit 159 is configured similarly to the class synthesizing circuit 126 of the image signal conversion unit 110 described above.

Further, the coefficient data generating device 150 outputs the first HD pixel data y as target pixel data obtained from the HD signal supplied to the input terminal 151, and the first HD pixel data y corresponding to each of the HD pixel data y. Tap selection circuit 15
From the prediction tap data (SD pixel data) xi selectively extracted in step 3 and the class code CL output from the class synthesizing circuit 159 corresponding to each HD pixel data y. Has a normal equation generation unit 160 for generating a normal equation (see equation (11)) for obtaining the coefficient data wi.

In this case, the learning data described above is generated by a combination of one HD pixel data y and its corresponding n prediction tap pixel data. Therefore, a large amount of learning data is registered in the normal equation generation unit 160. A normal equation is generated. Although not shown, by arranging a delay circuit for time alignment in the preceding stage of the first tap selection circuit 153, the SD pixel data supplied from the first tap selection circuit 153 to the normal equation generation unit 160 The timing of xi can be adjusted.

The coefficient data generating device 150 is supplied with the data of the normal equation generated for each class by the normal equation generating section 160, solves the normal equation generated for each class, and solves the normal equation for each class. A coefficient data determining unit 161 for obtaining coefficient data wi;
and a coefficient memory 162 for storing i. In the coefficient data determination unit 161, the normal equation is solved by, for example, a sweeping-out method, and coefficient data wi is obtained.

The operation of the coefficient data generator 150 shown in FIG. 16 will be described. An HD signal (525p signal or 1050i signal) as a teacher signal is supplied to an input terminal 151. The HD signal is subjected to horizontal and vertical thinning processing by a two-dimensional thinning filter 152, and the SD signal as an input signal is obtained. A signal (525i signal) is generated.

In this case, when the first conversion method (the 525p signal is obtained from the 525i signal by the image signal conversion unit 110 in FIG. 1) is selected, the two-dimensional decimation filter 152 performs the thinning process on the 525p signal. Thus, an SD signal is generated. On the other hand, when the second conversion method (a 1050i signal is obtained from the 525i signal by the image signal conversion unit 110 in FIG. 1) is selected, the two-dimensional decimation filter 152 performs a thinning process on the 1050i signal to generate an SD signal. Is generated.

In this case, the resolution of the image based on the generated SD signal corresponds to the resolution selection signal.
The higher the resolution indicated by the resolution selection signal, the lower the resolution of the image based on the SD signal generated by the two-dimensional thinning filter 152. As the resolution of the image based on the SD signal becomes lower, the image signal converter 110 shown in FIG.
Thus, coefficient data for increasing the resolution of the image based on the HD signal generated in step (1) is obtained.

From this SD signal (525i signal), the second
The tap selection circuit 154 selectively extracts data (SD pixel data) of a space class tap located around the target pixel related to the HD signal (525p signal or 1050i signal). In the second tap selection circuit 154, taps are supplied based on the selected conversion method supplied from the tap selection control circuit 156 and the tap position information corresponding to the motion class detected by the motion class detection circuit 158. Is selected.

The space class tap data (SD pixel data) selectively extracted by the second tap selection circuit 154 is supplied to the space class detection circuit 157. In this space class detection circuit 157, each SD pixel data as the data of the space class tap is subjected to ADRC processing, and regenerated as class information of a space class (mainly a class classification for representing a waveform in space). The quantization code Qi is obtained (see equation (1)).

The third tap selection circuit 155 uses the SD signal generated by the two-dimensional thinning filter 152
Data (SD pixel data) of a motion class tap located around the target pixel related to the HD signal is selectively extracted. In this case, the third tap selection circuit 155 selects a tap based on tap position information supplied from the tap selection control circuit 156 and corresponding to the selected conversion method.

The data (SD pixel data) of the motion class tap selectively extracted by the third tap selection circuit 155 is supplied to the motion class detection circuit 158. The motion class detection circuit 158 obtains the class information MV of the motion class (mainly a class classification for representing the degree of motion) from each SD pixel data as the data of the motion class tap.

The motion information MV and the above-described requantized code Qi are supplied to a class synthesis circuit 159. The class synthesis circuit 159 uses the motion information MV and the requantized code Qi to generate an HD signal (525p signal or 10
A class code CL indicating the class to which the pixel of interest pertaining to the 50i signal) belongs is obtained (see equation (3)).

The first tap selection circuit 153 converts the SD signal generated by the two-dimensional thinning filter 152
The data (SD pixel data) of the prediction tap located around the target pixel related to the HD signal is selectively extracted. In this case, the first tap selection circuit 153 selects a tap based on tap position information supplied from the tap selection control circuit 156 and corresponding to the selected conversion method.

Then, the HD supplied to the input terminal 151
Each HD pixel data y as target pixel data obtained from a signal, and data (SD pixel data) xi of a prediction tap selectively extracted by the first tap selection circuit 121 in correspondence with each HD pixel data y From the class code CL output from the class synthesizing circuit 159 corresponding to each of the HD pixel data y, the normal equation generating unit 160 generates a normal code for generating n coefficient data wi for each class. An equation is generated.

Then, the normal equation is solved by the coefficient data determination section 161 to obtain coefficient data wi for each class, and the coefficient data wi is stored in the coefficient memory 162 divided into addresses by class.

As described above, the coefficient data generator 150 shown in FIG. 16 can generate the coefficient data wi for each class stored in the information memory bank 135 of the image signal converter 110 shown in FIG.

In this case, the two-dimensional decimation filter 152 outputs the 525p signal or the 1-bit signal depending on the selected conversion method.
An SD signal (525i signal) is generated using the 050i signal. A first conversion method (obtains a 525p signal from the 525i signal in the image signal conversion unit 110) and a second conversion method (image signal conversion) The unit 110 can generate coefficient data corresponding to (a 1050i signal is obtained from a 525i signal).

The resolution of the image based on the SD signal generated by the two-dimensional thinning filter 152 can be changed by the resolution selection signal. Therefore, by sequentially changing the resolution of the image based on the SD signal and determining the coefficient data for each class, coefficient data for each class at a plurality of resolutions can be generated.

In the above-described embodiment, a linear linear equation is used as an estimation equation when generating an HD signal. However, a higher-order equation may be used as the estimation equation.

In the above embodiment, the SD signal (525i signal) is converted to the HD signal (525p signal or 1 signal).
050i signal), the present invention is not limited to this example, and the same applies to other cases where the first image signal is converted to the second image signal using an estimation formula. Of course, it can be applied.

[0149]

According to the present invention, when the first image signal is converted into the second image signal, the pixel data of the target pixel related to the second image signal is converted according to the resolution selected by the user. The user can arbitrarily adjust the resolution of the image based on the second image signal to a desired value as in the conventional adjustment of contrast, sharpness, and the like.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a television receiver as an embodiment.

FIG. 2 is a diagram for explaining a pixel positional relationship between a 525i signal and a 525p signal.

FIG. 3 is a diagram illustrating a pixel positional relationship between a 525i signal and a 1050i signal.

FIG. 4 is a diagram showing an example of a pixel positional relationship between 525i and 525p and a prediction tap.

FIG. 5 is a diagram illustrating an example of a pixel positional relationship between 525i and 525p and a prediction tap.

FIG. 6 is a diagram illustrating an example of a pixel positional relationship between 525i and 1050i and a prediction tap.

FIG. 7 is a diagram illustrating an example of a pixel positional relationship between 525i and 1050i and a prediction tap.

FIG. 8 is a diagram showing an example of a pixel positional relationship between 525i and 525p and a space class tap.

FIG. 9 is a diagram illustrating an example of a pixel positional relationship between 525i and 525p and a space class tap.

FIG. 10 is a diagram illustrating an example of a pixel positional relationship between 525i and 1050i and a space class tap.

FIG. 11 is a diagram illustrating an example of a pixel position relationship between 525i and 1050i and a space class tap.

FIG. 12 is a diagram illustrating an example of a pixel positional relationship between 525i and 525p and a motion class tap.

FIG. 13 is a diagram illustrating an example of a pixel positional relationship between 525i and 1050i and a motion class tap.

FIG. 14 is a diagram for explaining line double-speed processing when a 525p signal is output.

FIG. 15 is a flowchart showing a learning flow of coefficient data.

FIG. 16 is a block diagram illustrating a configuration example of a coefficient data generation device.

[Explanation of symbols]

100: television receiver, 101: system controller, 102: remote control signal receiving circuit, 105
... Reception antenna, 106 ... Tuner, 107
..External input terminals, 110, image signal converters, 11
DESCRIPTION OF SYMBOLS 1 ... Display part 111, 112 ... OSD circuit, 121 ... 1st tap selection circuit, 122 ...
2nd tap selection circuit, 123 ... 3rd tap selection circuit, 124 ... space class detection circuit, 125 ...
Motion class detection circuit, 126... Class synthesis circuit, 1
27 ... Estimation prediction operation circuit, 128 ... Line-sequential conversion circuit, 130-133 ... Register, 134 ... Coefficient memory, 135 ... Information memory bank, 150 ...
.Coefficient data generation device, 151 ... input terminal, 152
... two-dimensional thinning filter, 153 ... first tap selection circuit, 154 ... second tap selection circuit, 15
5 ... third tap selection circuit, 156 ... tap selection control circuit, 157 ... space class detection circuit, 158
... Motion class detection circuit, 159 ... Class synthesis circuit, 160 ... Normal equation generation unit, 161 ... Coefficient data determination unit, 162 ... Coefficient memory, 200 ...
Remote control transmitter

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Kazushi Yoshikawa 6-35 Kita Shinagawa, Shinagawa-ku, Tokyo F-term in Sony Corporation (reference) 5C063 AA01 AA11 BA04 BA06 CA01 CA16

Claims (19)

[Claims] 1. An image signal conversion apparatus for converting a first image signal composed of a plurality of pixel data into a second image signal composed of a plurality of pixel data, comprising: First data selecting means for selecting a plurality of first pixel data located around a target pixel relating to a signal; and the plurality of first pixel data selected by the first data selecting means.
Class detection means for detecting the class to which the pixel of interest belongs, based on the pixel data, resolution selection means for selecting the resolution of the image based on the second image signal, and the class detected by the class detection means An image signal conversion device, comprising: pixel data generation means for generating pixel data of the pixel of interest in accordance with the resolution selected by the resolution selection means. 2. The pixel data generating means has a memory for storing coefficient data of an estimation formula generated in advance for each combination of a class detected by the class detecting means and a resolution selected by the resolution selecting means. And
Coefficient data generating means for generating the coefficient data corresponding to the class detected by the class detecting means and the resolution selected by the resolution selecting means; and from the first image signal to the second image signal Second data selecting means for selecting a plurality of second pixel data located around the target pixel; and the coefficient data generated by the coefficient data generating means and the second data selecting means selected by the second data selecting means. Multiple second
2. The image signal conversion apparatus according to claim 1, further comprising: a calculating unit that calculates pixel data of the target pixel from the pixel data of the target pixel using the estimation formula. 3. The first coefficient data generating means stores coefficient data of the estimation formula generated in advance for each combination of a class detected by the class detecting means and a resolution selected by the resolution selecting means. A first data readout unit that reads coefficient data of each class corresponding to the resolution selected by the resolution selection unit from the first memory unit; and a first data readout unit that reads out the coefficient data. A second memory for storing coefficient data of each class, and second data reading means for reading coefficient data corresponding to the class detected by the class detecting means from the second memory. 3. The image signal conversion device according to claim 2, wherein: 4. The method according to claim 1, wherein the class detecting means includes the plurality of first
The image signal conversion device according to claim 1, wherein a level distribution pattern of the pixel data is detected, and a class to which the target pixel belongs is detected based on the level distribution pattern. 5. The image signal conversion apparatus according to claim 1, wherein said resolution selection means is configured to select said resolution by pressing an up key and a down key. 6. The image signal conversion apparatus according to claim 1, wherein said resolution selection means is configured to select said resolution by rotating a knob. 7. The image signal conversion device according to claim 1, further comprising display means for displaying a resolution selected by said resolution selection means. 8. An image signal conversion method for converting a first image signal composed of a plurality of pixel data into a second image signal composed of a plurality of pixel data, the method comprising: converting the first image signal into the second image signal; A first step of selecting a plurality of first pixel data located around the pixel of interest relating to the signal; and the pixel of interest based on the plurality of first pixel data selected in the first step. A second step of detecting a class to which the image belongs, and a third step of selecting an image resolution based on the second image signal.
And the class detected in the second step and the third class
And a fourth step of generating the pixel data of the pixel of interest in accordance with the resolution selected in the step (a). 9. In the fourth step, the class detected in the second step and the third
Generating the coefficient data corresponding to the resolution selected in the step; and, from the first image signal, converting a plurality of second pixel data located around the pixel of interest according to the second image signal Selecting; and generating the generated coefficient data and the selected plurality of second data.
And calculating the pixel data of the target pixel from the pixel data of the target pixel using the estimation equation. 10. The method according to claim 1, wherein in the second step, a level distribution pattern of the plurality of first pixel data is detected, and a class to which the target pixel belongs is detected based on the level distribution pattern. Item 9. The image signal conversion method according to Item 8. 11. The method according to claim 8, further comprising a fifth step of displaying the resolution selected in the third step. 12. An image signal input section for inputting a first image signal composed of a plurality of pixel data, and a second image signal composed of a plurality of pixel data, the first image signal being input from the image signal input section. Image signal conversion means for converting the image into an image signal and outputting the image signal; image display means for displaying an image based on the second image signal output from the image signal conversion means; Resolution selecting means for selecting a resolution, wherein the image signal converting means comprises: a plurality of first pixels located around a pixel of interest according to the second image signal from the first image signal; First data selection means for selecting data; and the plurality of first data selection means selected by the first data selection means.
Class detection means for detecting a class to which the pixel of interest belongs, based on the pixel data of the pixel of interest, and a pixel of the pixel of interest corresponding to the class detected by the class detection means and the resolution selected by the resolution selection means. An image display device comprising: pixel data generation means for generating data. 13. The pixel data generating means has a memory for storing coefficient data of an estimation formula generated in advance for each combination of a class detected by the class detecting means and a resolution selected by the resolution selecting means. And
Coefficient data generating means for generating the coefficient data corresponding to the class detected by the class detecting means and the resolution selected by the resolution selecting means; and from the first image signal to the second image signal Second data selecting means for selecting a plurality of second pixel data located around the target pixel; and the coefficient data generated by the coefficient data generating means and the second data selecting means selected by the second data selecting means. Multiple second
13. The image display device according to claim 12, further comprising: a calculating unit that calculates the pixel data of the target pixel from the pixel data using the estimation formula. 14. The method according to claim 1, wherein the class detecting means detects a level distribution pattern of the plurality of first pixel data, and detects a class to which the target pixel belongs based on the level distribution pattern. 13. The image display device according to 12. 15. The image display apparatus according to claim 12, further comprising display control means for displaying the resolution selected by said resolution selection means on a screen of said image display means. 16. The image display device according to claim 12, further comprising receiving means for receiving a broadcast signal to obtain the first image signal. 17. An apparatus for generating coefficient data of an estimation formula used when converting a first image signal consisting of a plurality of pixel data into a second image signal consisting of a plurality of pixel data, Signal processing means for processing a teacher signal corresponding to the first image signal to obtain an input signal corresponding to the first image signal; and resolution selecting means for selecting a resolution of an image based on the input signal obtained by the signal processing means. First data selecting means for selecting, from the input signal, a plurality of first pixel data located around the pixel of interest relating to the teacher signal; and the plurality of first pixel data selected by the first data selecting means. First
A class detecting means for detecting a class to which the pixel of interest belongs based on the pixel data of Data selection means, a class detected by the class detection means, the plurality of second pixel data selected by the second data selection means, and data of a pixel of interest according to the teacher signal, A coefficient comprising: a normal equation generating means for generating a normal equation for obtaining the coefficient data for each class; and a coefficient data calculating means for obtaining the coefficient data for each class by solving the normal equation. Data generator. 18. The signal processing means includes a Gaussian filter that performs vertical and horizontal decimation processing on the teacher signal to obtain the input signal corresponding to the first image signal. 18. The coefficient data generation device according to claim 17, wherein the selection unit selects a resolution of the image based on the input signal by selecting a standard deviation of the Gaussian filter. 19. A method for generating coefficient data of an estimation formula used when converting a first image signal composed of a plurality of pixel data into a second image signal composed of a plurality of pixel data, A first step of processing a teacher signal corresponding to the first image signal to obtain an input signal corresponding to the first image signal, and selecting a resolution of an image based on the input signal obtained in the first step. 2) a third step of selecting a plurality of first pixel data located around the pixel of interest relating to the teacher signal from the input signal; and a plurality of the first pixel data selected in the third step. A fourth step of detecting a class to which the pixel of interest belongs based on the first pixel data; and detecting a plurality of second pixel data located around the pixel of interest related to the teacher signal from the input signal. 5th step, the class detected in the 4th step, the plurality of second pixel data selected in the 5th step, and data of the pixel of interest according to the teacher signal. A sixth step of generating a normal equation for obtaining the coefficient data for each class; and a sixth step of solving the normal equation generated in the sixth step to obtain the coefficient data of each class. 7. A method for generating coefficient data, comprising: