JPH05236313A - Television system converter - Google Patents

Abstract

PURPOSE:To easily obtain a TV system converter which has an electronic beam function and a TV system exchange function by performing the scanning line conversion processing and the picture image conversion processing in a mode in accordant with the magnification of an electronic beam. CONSTITUTION:The input terminals N of the changeover switches 6, 7 and 14 are selected for acquisition of the NTSC system image signals. In this case, the output data of an A/D converter 4 are written into a and field memory 8 in an NTSC system and then, read out in the reference signal timing of the NTSC system. Meanwhile, an input terminal P is selected for acquisition of the PAL system image signals. The weighting coefficients are previously and separately prepared in both NTSC and PAL systems for interpolation required between a scanning line and a picture element. Then, the input terminals P or N of the changeover switches 25-50 and furthermore an input terminal NOR (NORMAL) or ZOOM are selected for acquisition of a desired weight coefficient.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television system conversion device, and more particularly to a television system conversion device for performing optimum conversion processing according to an electronic zoom magnification. 2. Description of the Related Art For example, an NTSC image signal is transmitted to a PA.
In order to convert to an L-system image signal, it is necessary to eliminate the difference between the specifications of both types as shown in FIG. 10 by interpolation or thinning processing. That is, when converting the NTSC system to the PAL system, the data amount of 1H is 85 in the NTSC system.
In contrast to the 8 pixels, the PAL method has 864 pixels, and therefore it is necessary to interpolate one pixel every 143 clocks (CLK). The number of scanning lines in one field is NTS
Since there are 262.5 lines in the C method and 312.5 lines in the PAL method, one line is interpolated for every five lines.
The field frequency is 59.94 Hz (1
While it is 6.7 msec cycle), in the PAL system, it is 50.0 Hz (20 msec cycle), and therefore it is necessary to perform one-field thinning processing every 6 fields. FIG. 11 shows a processing mode of the above-mentioned scanning line interpolation processing. In such an interpolation process, an interpolation process using two adjacent NTSC scan lines is performed to generate 6 PAL scan lines from 5 NTSC scan lines. That is, since the 0th and 5th scanning lines of the NTSC system coincide with the 0th and 6th scanning lines of the PAL system, no interpolation processing is required, but the 1st scanning line of the PAL system is used. -To generate the fifth scan line, it is necessary to perform interpolation processing using two adjacent NTSC scan lines including the scan line. At that time, in order to suppress deterioration of image quality, interpolation is performed with weighting according to the distance between the scanning line and each of the two scanning lines of the NTSC system. For example, since the scan line of the 1st PAL system corresponds to the distance 0.833 from the 0th scan line to the 1st scan line, the weight of 0.167 is assigned to the 0th scan line. Multiply by the coefficient and 0.
The weighting coefficient of 833 is multiplied, and both multiplication results are added to obtain the first PAL scanning line. Similarly, the first NTSC scan line is multiplied by a weighting factor of 0.333, the second NTSC scan line is multiplied by a weighting factor of 0.667, and the result of addition of the two is the second PA.
L scan lines will be obtained. Similarly, the third
The 5th to 5th PAL scan lines are obtained. Such interpolation processing is also applied when converting the data amount of 1H from 858 pixels of NTSC system to 864 pixels of PAL system. FIG. 12 shows a field frequency conversion processing mode. NTSC system field cycle 1
In order to convert 6.7 msec into 20 msec of the PAL system, field thinning processing is performed as shown in the figure.
That is, when each of the 1 to 5 fields of the NTSC system is converted into a field of 20 msec, the fifth field conversion end timing of the PAL system coincides with the sixth field end timing (100 msec) of the NTSC system, and eventually the NTSC system Six fields are not needed. Therefore, the conversion of the field frequency is performed by the field thinning process. FIG. 13 shows PAL from the conventional NTSC system.
The block diagram of one structural example of the conversion apparatus to a system is shown. NTS
The input Y signal of the C method is converted into a digital signal at a sampling frequency of 13.5 MHz, and the field memory 5
Written to 2. This writing is performed at the NTSC rate clock timing from the write controller 53. Reading from the field memory 52
It is performed at the PAL rate clock timing from the read controller 54. The writing and reading of the field memory 52 completes the conversion of the field frequency. The data read from the field memory 52 is subjected to the above-described scanning line interpolation processing in the scanning line interpolation processing unit including the 1H delay unit 55, the multipliers 56 and 57, and the adder 58. Read controller 54
From the weighting factors K and 1-K supplied to the multipliers 56 and 57 from
Corresponds to the weighting coefficient shown in FIG. The data subjected to the scanning line interpolation processing from the adder 58 is the 1-clock delay unit 59 and the multipliers 60, 6
In the pixel interpolation processing unit including 1 and the adder 62,
Interpolation processing based on two adjacent pixel data is performed by the same circuit operation as the above scanning line interpolation processing. Here, the weighting factors k and 1-k supplied from the read controller 54 to the multipliers 60 and 61 are determined by the same criteria as K and 1-K. The weighting coefficient used in the above interpolation process is usually stored in the ROM. This ROM
FIG. 14 and FIG. 15 show the relationship between the storage of the weighting coefficient in the address, the address (V address, H address) and the outputs of the adders 58 and 62. 14 shows the scanning line interpolation processing, and FIG. 15 shows the pixel interpolation processing. In this way, the conversion from the NTSC system to the PAL system is completed by the conversion processing on the specifications of the field frequency, the scanning line, the number of pixels, etc. as shown in FIG.
The converted output data from the adder 62 is converted into an analog signal at a 13.5 MHz clock in the D / A converter 63, and a PAL system image signal is obtained. Although the above description is for the Y signal, the same conversion is performed for the C signal to obtain the PAL C image signal. [0008] As described above, in the television type conversion device such as the conversion from the conventional NTSC system to the PAL system, the conversion processing of the field frequency, the scanning line and the pixel data number is performed. Has been applied. by the way,
In recent years, image processing apparatuses are often equipped with an electronic zoom function. When the electronic zoom is performed, the weighting coefficient in the above conversion processing is different and cannot be simply handled. This problem is not limited to the conversion from the NTSC system to the PAL system, and is similar to other television system conversion devices. Therefore, an object of the present invention is to simplify the configuration of a device having both an electronic zoom function and a television system conversion function. In order to solve the above-mentioned problems, the television system converter according to the present invention has one condition that it has a first number of scanning lines and a first number of horizontal pixels. The image information according to the first television system defined as is converted into the image information according to the second television system defined as one condition that the second scanning line number and the second horizontal pixel number are provided. Therefore, a predetermined interpolation calculation process is performed on each position information and level information regarding each scanning line according to the first television system, and then the second information is obtained.
Scanning line conversion processing means for forming respective position information and level information regarding each scanning line conforming to the television system, and respective position information and level information regarding each horizontal pixel according to the first television system. A television system conversion device having pixel conversion processing means for performing predetermined interpolation calculation processing to form respective position information and level information regarding each pixel compatible with the second television system, The scanning line conversion processing means and the pixel conversion processing means are configured to execute the scanning line conversion processing and the pixel conversion processing according to the zoom magnification set by the electronic zoom magnification setting means. According to the present invention, a part of the electronic zoom function is utilized by performing the scanning line conversion processing and the pixel conversion processing required for the television system conversion in a mode according to the set electronic zoom magnification. It enables the conversion of television systems. The present invention will now be described with reference to the drawings. FIG. 1 is a configuration block diagram of an embodiment of a television system conversion apparatus according to the present invention. The image formed on the image sensor (CCD) 2 of the NTSC system via the optical lens 1 is converted into an electric signal (image signal) to be converted into the NTS.
It is supplied to the C type imaging process circuit 3. The image pickup process circuit 3 performs well-known image pickup processing such as Y / C separation on the image signal, and outputs the obtained Y signal to the A / D converter 4. The digital signal (image data) from the A / D converter 4 is transferred to the first field memory 5
Written in. The SSG circuit 10 generates a reference signal for NTSC system operation, defines the operation of the imaging process circuit 3, and defines the operation of the drive circuit 9 that drives the CCD 2. Further, the reference signal from the SSG circuit 10 is
It is sent to the line controller 11 and controls the timing of writing data to the first field memory 5. A changeover switch 6 is provided between the first field memory 5 and the second field memory 8, and the terminal N of the two input terminals on the side of the first field memory 5 is the A / D converter 4. Output (input of the first field memory 5) is connected, and the terminal P is connected to the output of the first field memory 5. An SSG circuit 12 for generating a reference signal for PAL system operation is provided, and the read / write controller 13 is controlled by the output reference signal. The read / write controller 13 defines the read timing of the first field memory 5, and also defines the write timing of the second field memory 8 supplied to the second field memory 8 via the changeover switch 7. The input terminal P of the changeover switch 7 is connected to the output of the read / write controller 13, and the input terminal N is connected to the output of the write controller 11.
The reference signal from the SSG circuit 12 is supplied to the input terminal P of the changeover switch 14, the reference signal from the SSG 10 is supplied to the input N terminal, and the reference signal from the selected terminals P and N is supplied to the read controller 15. It The read controller 15 generates a reference signal for controlling the second field memory 8 for pixel interpolation when compatible with electronic zoom described later,
The read timing from the second field memory 8 is defined. The changeover switches 6, 7 and 14 are NTSC.
The input terminal N is selected when a system image signal is desired,
The input terminal P is selected when an image signal of the PAL system is desired. For example, when it is desired to obtain an NTSC image signal, the input terminals N of the changeover switches 6, 7 and 14 are selected. At this time, the output data of the A / D converter 4 is written in the second field memory 8 by the NTSC system reference signal from the write controller 11, and the read from the second field memory 8 is performed by the read controller 15.
From the NTSC standard signal timing.
When it is desired to obtain the PAL system image signal, the input terminals P of the changeover switches 6, 7 and 14 are selected. At this time, the writing to the first field memory 5 is NTSC.
It is performed at the reference signal timing, the reading is performed at the PAL reference timing, and the writing to the second field memory 8 is also performed at the PAL reference signal timing. Second
The reading from the field memory 8 is performed at the PAL reference signal timing from the read controller 15. The output data from the second field memory 8 has its scanning line interpolated by a scanning line interpolation processing unit having a 1H delay unit 16, multipliers 17 and 18 and an adder 19 having the same circuit configuration as described above. 1 clock delay 20,
A digital signal in which pixels are interpolated by a pixel interpolation processing unit including the multipliers 21 and 22 and the adder 23, and the image signal obtained by the adder 23 and subjected to the electronic zoom process is converted from the NTSC system to the PAL system. Is a D / A converter 2
At 4, it is converted into an analog signal and output to the recording system. The read controller 15 is controlled by the V address data and the H address data obtained by the following processing to give the read address data and timing to the second field memory 8. As shown in Figure 2,
Normal state (NORMA) in scanning line (V) direction interpolation and pixel (H) direction interpolation of NTSC system and PAL system
L) and the weighting coefficient at the time of 2 × zoom (ZOOM) change. Therefore, in the present embodiment, the weighting coefficient is prepared separately for the NTSC system and the PAL system in advance, and the input terminals P or N of the changeover switches 25 to 30, and further the input terminal NOR (NORMAL) or ZOOM
Is selected to obtain a desired weighting coefficient. That is, in the NTSC NORMAL state, the V and H direction interpolation coefficients are each “1”, and in the 2 × zoom state, both coefficients are 0.5.
Are obtained as V data and H data from the adders 31 and 3
2 is supplied to one input terminal. The outputs of the adders 31 and 32 are delayed by the 1H delay device 33 and the 1-clock delay device 34, respectively, and the respective outputs are supplied to the other input terminals of the adders 31 and 32. The integer parts of the data obtained from the 1H delay device 33 and the 1-clock delay device 34 are output to the other input terminals of the adders 37 and 38, respectively. The fractional part of the data obtained from the 1H delay unit 33 and the 1-clock delay unit 34 is used as the weighting factors K and k, respectively, in the multiplier 1
7 and 21, the subtractors 35 and 36 perform subtraction processing from 1 and output to the multipliers 18 and 22 as 1-K and 1-k weighting factors, respectively. In the adders 37 and 38, the integer part supplied to each one input terminal and 1 are added and the added data is supplied to the read controller 15 as the V address data and the H address data. Similarly, P
In the AL system NORMAL state, the coefficient in the V direction is 0.8.
33 and the coefficient 0.933 in the H direction are selected, and in the case of the 2 × zoom, 0.417 and 0.497 are selected, and the V address data and the H address data are supplied to the read controller 15. The configuration shown in FIG. 1 shows the processing system for the Y signal obtained by the image pickup process section 3, but the processing is the same for the C signal, and its configuration block diagram is shown in FIG. .. In FIG. 3, the A / D converter 4C,
First field memory 5C, changeover switch 6C, second
Field memory 8C, 1H delay device 16C, multiplier 1
7C, 18C, 21C, 22C, 1-clock delay unit 20
The C and the adders 19C and 23C are respectively the A / D converter 4, the first field memory 5, the changeover switch 6, the second field memory 8 and the 1H delay device 1 in FIG.
6, it has the same function as the multipliers 17, 18, 21, 22, 1-clock delay unit 20 and the adders 19, 23. Also,
The control circuits of the first field memory 5C and the second field memory 8C are the same circuits as in FIG. The C signal thus obtained from the adder 23C is decoded by the NTSC encoder 39 and the PAL encoder 40, respectively, and the input terminals N and P of the changeover switch 41 are decoded.
Are output respectively. The changeover switch 41 is NTSC
The outputs from the encoder 39 and the PAL encoder 40 are selectively output, converted into an analog signal by the D / A converter 24C, and output to the recording system. FIG. 4 is a block diagram showing the configuration of another embodiment of the television system converter according to the present invention. Figure 1
In contrast to the embodiment shown in FIG. 2, the coefficient data is set in advance corresponding to the NTSC system, the PAL system and the electronic zoom magnification, and desired coefficient data is selected from among them by the changeover switch. In the present embodiment, the zoom switch 42 is provided, and the microcomputer 43 receives the zoom magnification information from the zoom switch 42, and the built-in ROM is stored in advance.
The coefficients stored in the above are selected and supplied to the adders 31 and 32 as V data and H data. A change-over switch 44 for setting the NTSC system and the PAL system is connected to the microcomputer 43, and the NTSC system is set when the terminal N is selected and the PAL system is set when the terminal P is selected. FIG. 5 shows the relationship between the writing of the first field memory 5 and the writing and reading timing of the second field memory 8 in the embodiment shown in FIGS. Writing to the first field memory 5 is performed in the NTSC system 16.7 msec cycle. Further, the reading from the first field memory 5 is performed at a cycle of 20 msec of the PAL system, and the writing to the second field memory 8 is also performed in this 2
It is performed at a cycle timing of 0 msec. As a result, as described above, the sixth image data of the NTSC system is thinned out. FIG. 6 shows that in the embodiment shown in FIG.
NTSC zoom data corresponding to addresses that change up to 256, and PAL V data and H data are stored. The ROM address “0” has a zoom ratio of 1 ×,
ROM address “256” corresponds to a zoom factor of 2
The zoom magnification of 1 to 2 is divided into 256. NT
In the case of the SC system, the zoom data is set to 1.00 for zoom magnification of 1 and 0.500 for zoom magnification of 2. On the other hand, in the PAL system, V data is multiplied by 0.83 and H data is multiplied by 0.993 with respect to NTSC system data. FIG. 7 shows the operation timing of the microcomputer 43 of FIG. Teleswitch (SW) of electronic zoom switch that operates with VSYNC as the reference clock
When is operated, the zoom is increased and the ROM address is 1
Is incremented by one. On the contrary, the wide switch (S
When W) is operated, the address of the ROM is lowered by 1 and zoomed down. FIG. 8 is a block diagram showing the configuration of still another embodiment of the television system converter according to the present invention.
The present embodiment is applicable to a reproducing device such as a VTR instead of the image pickup device, and the image pickup system (optical lens 1, CCD 2, image pickup process unit 3, drive circuit 9) of the embodiment shown in FIG. 1 is deleted. The reproduced Y signal is directly input to the A / D converter 4. In addition, the zoom switch 42 and the microcomputer 43 of FIG.
And a changeover switch 44 are provided. The converted data obtained from the adder 23 is converted into an analog signal by the D / A converter 24, and then added with the C signal processed in the same manner as described above in the adder 45 to output a video signal. FIG. 9 shows a block diagram of a processing system for the reproduced C signal similar to that of FIG. 8, and the basic configuration is the same as that of FIG. The reproduced C signal is converted into digital data by the A / D converter 46 and then decoded by the decoder 47 to convert the color difference (RY / BY) signal into the first field memory 5C and the changeover switch 6C. Supply to the input terminal N. Other configurations are similar to those in FIG. 3, and the analog signal obtained by the D / A converter 24C is supplied to another mixing system such as the adder 45 in FIG. As described above, in the television system conversion apparatus according to the present invention, the scanning line conversion process and the pixel conversion process necessary for the television system conversion are performed in accordance with the set electronic zoom magnification. Therefore, a device having both an electronic zoom function and a conversion function of a television system can be configured very easily.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a configuration block diagram showing an embodiment of a television system converter according to the present invention. FIG. 2 is a block diagram showing a basic configuration of a conversion processing unit for a C signal in the embodiment shown in FIG. FIG. 3 is a block diagram showing a basic configuration of a conversion processing unit for a C signal in the embodiment shown in FIG. FIG. 4 is a configuration block diagram showing another embodiment of the television system converter according to the present invention. FIG. 5 is a diagram showing write / read timing of the field memory in the embodiment of the present invention. 6 is a diagram showing an example of data stored in a ROM in the microcomputer of the embodiment shown in FIG. 7 is a diagram showing the timing of the microcomputer operation of the embodiment shown in FIG. FIG. 8 is a third television system converter according to the present invention.
3 is a configuration block diagram showing an embodiment of FIG. 9 is a configuration block diagram of a basic part of a C signal processing system of the embodiment shown in FIG. FIG. 10 is a diagram showing a difference in specifications between the NTSC system and the PAL system. FIG. 11 is a diagram showing a mode of scanning line interpolation processing from the NTSC system to the PAL system. FIG. 12 is a diagram showing a field thinning processing mode for field frequency conversion from the NTSC system to the PAL system. FIG. 13 is an example configuration block diagram showing a conventional NTSC system to PAL system conversion device. FIG. 14 is a diagram for explaining a weighting coefficient, an address, and an operation stored in the ROM in the scanning line interpolation processing in the conventional conversion device. FIG. 15 is a diagram for explaining a weighting coefficient, an address, and an operation stored in the ROM in the pixel interpolation processing in the conventional conversion device. [Explanation of reference signs] 4,46 A / D converter 5, 5C, 8, 8C Field memory 6, 7, 14, 25 to 30, 41, 44 Changeover switch 10 (NTSC) SSG circuit 11 Write controller 12 (PAL) SSG Circuit 13 Read / write controller 15 Read controller 24 D / A converter 39 NTSC encoder 40 PAL encoder 42 Zoom switch 43 Microcomputer 45 Adder 47 Decoder

Claims (1)

What is claimed is: 1. Having a first number of scan lines and a first number of horizontal pixels
The image information according to the first television system defined as one condition is converted into the image information according to the second television system defined as one condition that it has the second scanning line number and the second horizontal pixel number. In order to perform conversion, a predetermined interpolation calculation process is performed on each position information and level information regarding each scanning line according to the first television system, and each position information and level information regarding each scanning line according to the second television system are converted. Scanning line conversion processing means for forming position information and level information; and a second interpolation processing for performing predetermined interpolation calculation processing on each position information and level information regarding each horizontal pixel according to the first television system. Pixel conversion processing means for forming respective position information and level information regarding each pixel compatible with the television system. In the system conversion device, the scanning line conversion processing means and the pixel conversion processing means are configured to execute the scanning line conversion processing and the pixel conversion processing according to the zoom magnification set by the electronic zoom magnification setting means. A television conversion device characterized by the above.