JPS59181789A - Television signal processing system - Google Patents

Abstract

PURPOSE:To obtain a television signal which generates no flicker by obtaining a signal of a line sequential scanning by an image pickup device, converting it to a television signal of an interlaced scanning by using a storing circuit, transmitting it, converting it to a signal of a line sequential scanning of a frame frequency of (n) times of a frame frequency in an image receiving side, and reproducing a picture. CONSTITUTION:Both of buffer storing circuits 213, 215 are storing circuits which have a storage capacity of a picture element of half of one scanning line, and can set independently a speed of write and a speed of read-out, and constituted of a semiconductor random access storage integrated circuit, a magnetic core random access storage device, etc. A television signal 201 and 204 are read to the center of a scanning line in a 0.5 scanning line buffer storing circuit 213 and 215, respectively, read out at a speed of two times to an output 213' and 215', respectively, and when the output 213' and 215' are switched and outputted alternately by a half period of a horizontal period by using a switching circuit 224, a converted television signal 225 which sets one field as one new frame and does not execute an interlaced scanning is obtained as shown by a waveform 225.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a television signal processing system, and more specifically, to a signal processing system for converting a television signal into a television signal that provides better image quality without causing eye fatigue. It is.

[Background of the invention]

Current standard television systems employ interlaced scanning to reduce the required frequency band. As a result, flickering appears in parts of the screen that change rapidly vertically.

The reason why flickering occurs will be explained using FIG. 1st
In the figure, the scanning line group 1 of the first field is sequentially scanned, then the scanning line group 2 of the second field located in the middle of the scanning line group 1 is sequentially scanned, and the scanning line group 1 of the first field is sequentially scanned. is scanned, and so on. Therefore, if the screen changes suddenly in the vertical direction, for example from black at the top to white at the bottom, as shown in Figure 1, the change from black to white in the first field 3 and the location of the change from black to white in the second field 4 are shifted by one scanning line interval. Therefore, the location of the change in black and white moves up and down with the frame period, which causes a flicker to appear in areas of the screen where there is a sudden vertical change.

The above-mentioned flicker does not bother you much on a normal screen, but it becomes very noticeable on a screen where many horizontal lines are arranged regularly or near-horizontal lines are concentrated at one point. It also causes eye fatigue when viewing television images for a long time.

[Purpose of the invention]

Therefore, an object of the present invention is to realize a television signal processing method for obtaining a flickering-free television signal from a television signal employing interlaced scanning.

[Summary of the Invention] In order to achieve the above object, the present invention obtains a line-sequential scanning signal using an imaging device, converts it into an interlaced scanning television signal using a memory circuit, and transmits the signal. L,
On the image receiving side, an image is constructed by converting it into a line-sequential scanning signal with a frame frequency n times the frame frequency of the television signal.

In the following example, the ink race will be explained in the case of 2:1, which is generally practiced at present, but the present invention
(n>An integer greater than or equal to 2): The case of 1 can also be realized.

[Embodiments of the invention]

The 21st step is a part that converts the line-sequentially scanned image signal, which is the output of the image pickup device on the transmitting side, into a 2=1 incremented television signal in an embodiment of the television signal processing method according to the present invention. FIG. 2 is a configuration diagram showing the configuration of.

Three primary color signals 101.10 from an imaging device that does not perform interlaced scanning, that is, scans the frame sequentially from top to bottom.
2 and 103 are a luminance signal 105 and two color signals 106 by a generally known matrix circuit 104.
and 107. Signals 105, 106 and 107 are sent to a buffer memory circuit 108 with a capacity for one field.
, 109 and 110, respectively.

Buffer memory circuits 108, 109, and 110 read every other scanning line to outputs 114', 115°116 using a timing signal 113 generated by a timing generation circuit 112 from a synchronization signal 111, and convert the signal into an interlaced scanning signal. Convert. Outputs 115 and 116 corresponding to the two color signals are applied to a commonly known modulation circuit 117 and converted into a carrier color signal 118. The output 114 corresponding to the luminance signal and the carrier color signal 118 are summed by an adder circuit 119 to form a composite color television signal 12.
It becomes 0. That is, 525 signals scanned every 1/30 seconds are stored in the buffer memory circuit, 108, 109, 110.
262. is recorded and every other scanning line is read out.
Five signals are read out in 1/60 second to obtain one field of image signals, and the remaining 262 signals are read out in the next 1/60 second.
．． Five broadcasts are output one after another and converted into an 1-field signal. By repeating this process, an interlaced signal similar to a normal television signal is obtained.

In FIG. 2, even if the order of the matrix circuit 104 and the one-field buffer memory circuits 108, 109, and 110 is reversed, the prescribed operation will still occur, but the band of the three buffer memory circuits must be made the same as that of the luminance signal. Therefore, the circuit scale increases.

FIG. 3 shows a color television signal generated by the conversion circuit shown in FIG. 2, which is subjected to interlaced scanning, and which is separated into a luminance signal and a chrominance signal by a known luminance and chrominance signal separation circuit. 2 is a drawing showing the configuration of a conversion circuit for converting into a scanning (scanning) signal.

In FIG. 3, an input signal 201 is generated by two one-field delay circuits 202 and 203 into a signal 204 delayed by one field and a signal 205 delayed by two fields. Input signal 201 and signal 204 delayed by 1 field become two inputs of switch circuit 206, and signal 204 delayed by 1 field and signal 205 delayed by 2 fields become two inputs of switch circuit 207. Become. Switch circuits 206 and 207 are controlled by a vertical synchronization signal 208 and connect input signal 201 and field-delayed signal 204 to outputs 209 and 210, respectively, when the one-field delayed signal is present in the first field. . Also, the signal 2 delayed by 1 field
04 in the second field, the signal 204 delayed by 1 field and the signal 2 delayed by 2 fields.
05 to outputs 209 and 210, respectively. Therefore, the second field and first field of the same frame always appear in the outputs 209 and 210.

Outputs 209 and 210 are output to scan line buffer circuits 213 and 2.
15 and the switch circuit 224 will be explained below.

In FIG. 4, for convenience of explanation, the same parts as the switch 206.2 in FIG. 2 are given the same numbers).

As mentioned above, the signals 209 and 210 are generated from the second field and the second field in the same frame, respectively, and due to the relationship between the number of scanning lines and the field period, these are separated by 180 degrees as shown in Figure 4. There is a phase difference so that adjacent scanning lines exist at the same time.

Yo/l...? /N- buffer memory circuits t71 and Q-U are both memory circuits that have a storage capacity of half the pixels of a -scanning line and can make the write speed and read speed independent, and are semiconductor random access memory integrated circuits. , a magnetic core random access storage device, etc. The reason why a storage capacity of 0.5 scanning lines is sufficient is that after reading out the remaining portions, it is sufficient to sequentially read in the remaining portions. Therefore, the storage capacity for one scanning line is prepared.
If so, there is no need to write after reading, and the control circuits for the buffer memory circuits 213 and 215' can be simplified.

In order to drive these buffer memory circuits 213, j15 and switch circuit 224, a horizontal synchronizing signal 227 is separated from the television signal 201 in a synchronizing signal separation circuit 226, and is used to synchronize with the horizontal synchronizing signal in a clock generating circuit 228. A clock signal 229 is generated to control writing.

Also, reading is performed at twice the speed of the above clock signal. Also, from the horizontal synchronization signal separated by the quadrupler 230,
A synchronization signal 231 having a period half that of the horizontal synchronization signal is generated to control the switch circuit 224.

Therefore, the television signals 201 and 204 are read into the 0.5 scan line buffer storage circuits 213 and 215, respectively, up to the center of the scan line, and the waveforms 213' (dashed line) in FIG. 4 are output to the outputs 213' and 215', respectively. 215'(
The speed is doubled as shown in solid line).

If the switch circuit 224 is used to alternately switch and output the outputs 213' and 215' at half the horizontal period, one field will be converted into one new frame as shown in the waveform 225. A converted television signal 225 is obtained without interlacing.

The present invention will be described above with reference to examples.1. However, the present invention is not limited to the above-mentioned embodiments, and the present invention also includes application to only the luminance component of a television signal or the low frequency portion of the luminance component, as long as the 17ii7 quality allows. . Further, although the embodiments have been described with respect to a 2:1 interlaced television signal, the present invention generally applies to a ne I interlaced case as well. In this case, the conversion circuit on the transmitting side requires buffer memory circuits for (11-1) fields, and the receiving side requires 2(n-1) field delay circuits.

In addition, although the detailed explanation of the present invention will be explained without distinguishing between analog processing and digital processing, when performing processing that involves digital processing and sampling, an AD conversion circuit, a DA conversion circuit, and a mudwave circuit are required. becomes. However, how to use these circuits is a matter of common knowledge for engineers in related fields, so I have omitted the explanation.

〔Effect of the invention〕

The present invention transmits the output of a progressive scanning television imager as an interlaced signal, and reproduces it as a progressive scanning television signal at the receiver. Images can be played back without flickering.

[Brief explanation of the drawing]

Figure i1 is a diagram explaining conventional interlaced scanning, and Figures 2 and 3 are diagrams showing the configurations of signal conversion circuits on the transmitting side and receiving side, respectively, in the television signal processing system according to the present invention. The figure is a block diagram of the signal conversion circuit shown in FIG. 3 above. FIG. 5 is a waveform diagram showing the operation of FIG. 3. 1
04...Mathrix circuit, 108, 109,
110...Buffer memory circuit, 112...
Timing generation circuit, 117...Modulation circuit, 2
02,203...Filled delay-Raku/ 1"1 2θl 嵜 2j fig. 3 fig. 2θl 1tj/

Claims (1)

[Claims] 1. On the transmitting side, a line-sequential image signal obtained by an image pickup device is converted into an incremented television signal in which one frame consists of n fields, and on the receiving side, the television signal is converted to an incremented television signal with a frame frequency. A television signal processing method for converting the television signal into a line sequential scanning signal n times the frame frequency of the television signal. 2. In the television signal processing method described in paragraph 1, on the receiving side, the input first television signal, the second television signal delayed by one field from the first television signal, and the first television signal. When the second television signal is the signal of the first frame, the first and s2 television signals are obtained, and the second television signal is delayed by two fields. If it is a frame signal, the second
and selecting two television signals from the first, second, and third television signals such that a third television signal is generated;
1 time for each of the two TV signals selected above
A television signal processing method that converts the two compressed television signals into a time-series television signal by alternating the two compressed television signals in scanning line units.