JPS6086982A - Print method of video signal - Google Patents

Abstract

PURPOSE:To perform recording in a short time and with a simple constitution by reading out plural lines horizontally or vertically to a screen within one field time of a video signal and at the same time recording the video signal equivalent to one line within the time of a prescribed multiple as much as the one field time to feed paper. CONSTITUTION:Synchronizing signals of a frame are extracted by a video synchronizing separator circuit 1 and sent to a frequency multiplier 2A. Thus a signal of an n-fold frequency is obtained. Then a pulse is detected for each one line record by a rotational frequency detecting sensor 7 to a rotational frequency detecting disk 6 as well as a DC motor 5 connected directly to a paper feed drum 4. This detected pulse is m-multiplied by a frequency multiplier 2B. These two types of signals are sent to a frequency comparator 3 to produce the voltage proportional to the difference between both signal frequencies. This voltage is supplied to a motor controller 8 to change the rotational frequency of the motor 5.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a video signal printing method, and relates to a video signal printing method for efficiently recording video signals of televisions, CRT displays, etc. .

[Background of the invention]

Video signals such as those from televisions are scanned horizontally over one screen, and are usually scanned at 92 degrees using interlaced scanning.
One screen (one frame) is scanned every time (two fields). When printing this image with a line array recording head, it is necessary to read out and record one horizontal or vertical line of the image within one frame time from the video signal repeatedly, or use a buffer memory to parallelize recording and reading. Sometimes it is done.

However, in general, the recording time of one line rarely coincides with the time of one frame of the signal, and there is free time for viewing either of them.

Here, (a) and (b) of FIG. 1 are explanatory diagrams of the temporal relationship between the time of one frame of the video signal and the recording time of one line.

That is, (a) is the case when the recording time is longer than the frame time, and (b) is the opposite case.

In case (a), it can be handled by having two sets of buffer memories, and the total recording time is determined by the recording time of one line.

However, in the case of (b), two methods are possible.

That is, in the first method, one line is recorded within the time of each frame of the video signal, and the total recording time is determined by the time of the frame of the video signal, and even if there is recording capability, the speed of the signal is limited. The total recording time is fixed, which is inefficient.

In addition, the second method is to read data of multiple lines within the time of a frame.In this method, it is necessary to record the data in order, but the video signal and the start signal of the recording are Since the temporal relationship between the two terminals changes in a complicated manner, data exchange is extremely troublesome, and the circuit becomes complicated.

In other words, if the frequency of the synchronization signal of the video signal and the recording frequency are different, a so-called beat will be generated.In this case, at a certain point, it is necessary to determine which side of the waveform of the beat This requires a circuit to store the video signal in memory, and a circuit to store it in memory (for example, to determine how many times the video signal should be sampled and stored in memory).

[Purpose of the invention]

The present invention has been developed in view of the above-mentioned points, and an object of the present invention is to provide a video signal printing method that has a simple configuration and can record in a short time.

[Summary of the invention]

The key point of the present invention is to establish a certain relationship between the signal time of one frame and the recording time of one line, so that reading and recording of the video and minute signals can be carried out efficiently, and recording can be done in a short time. It is something.

A video signal printing method according to the present invention is applied to a video printer that records video signals horizontally or vertically one line at a time.
Within the frame time, multiple lines are read out horizontally or vertically of the image, and n 7m (n,
m is an integer, which means that one line is recorded in n (m) times the time and the paper is fed.

It should be noted that the present invention provides a constant n of a video signal.
For each piece, data is read m times and recorded 111 times.

[Embodiments of the invention]

Embodiments of the video signal printing method according to the present invention will be described with reference to the drawings.

First, FIG. 2 is an explanatory diagram showing the temporal relationship between the time of one frame of the video signal and the recording time according to an embodiment of the video print method of the present invention, and FIG. 1 is a synchronous partial configuration diagram of a video printer used for implementing the method.

In other words, if you arbitrarily set the recording time of one line for the time of one field or frame of a video signal, if the start of both coincides at a certain time, the next coincident time will be the same as each other. After an integer multiple,
The matching times vary depending on the combination.

From this, n and m are integers, n (where m is the recording time of one line'), and 'k is set to 17m times the time Tf of one field or one frame of the video signal. be.

In other words, the recording time of one line is set within the time T+ related to the period of the signal of one field or one frame, at a time T that is n/m times that time T.
One line of data is read m times and recorded m times for n video signals.

Therefore, in this case, it is preferable that the values of n and m are as small as possible.

In Figure 2, in the case of n=22m=3, 3
It is designed to record lines.

As a result, it has two sets of buffer memories, and alternately reads three lines in the rear frame of the two frames.
Writing takes 2/3 of the time compared to recording 1 frame K 1 line.

In this case, paper feeding is also performed at the same time as recording.

An embodiment in which paper is fed using a DC motor will be described with reference to FIG. 3.

In the figure, 1 is a video synchronization separation circuit; 2. A', 2B are
3 is a frequency comparator, 4 is a paper feed citram, 5 is a DC motor, 6 is a rotation speed detection disc, 7 is a rotation speed detection sensor, and 8 is a motor control device. The rotation speed detection disk 6 and the rotation speed detection sensor 7 are related to the rotation speed sensor.

That is, when a pulse motor is used to feed the paper, intermittent feeding is possible, so it is easy to match the start time of each frame of the video signal, but there is a drawback that the motor becomes large.

It was designed to use

Controlled by the motor control device 8 to meet the conditions described below,
This is to synchronize them.

That is, the video synchronization separation circuit 1 extracts one frame of synchronization signal and sends it to the one-frequency converter 2A, thereby creating a signal with a frequency n times higher. A DC motor 52 directly connected to the paper feed drum 4 detects a pulse at a rate of once per 1 ry/min of rotation speed detection sensor 7 to the rotation speed detection disk 6, and the frequency multiplier 2B Multiply by m. These two types of signals are sent to the frequency comparator 3 and compared to the frequency difference, the recording time of one line 'ff:
T,, the time of one frame is Tf, '■', --T
r Re... (1) 1 n and m are integers, and n(m).

With this configuration, as described below, the total recording time can be shortened, efficient printing is possible, and the circuit system for reading and printing signals can be made relatively simple. It is.

That is, in the above, the total recording time is the recording time Tv of one line x the total number of lines, but if one line is written within the recording time of one frame as in the past, the time saved is ( 'i''f-'t, ) x total number of lines.

Here, we are considering the case where TI > T, so T,
If it is set to 2/3 of Tf, it can be shortened by 1/3 of Tf.

In addition, since both start pulses coincide in time once every integer number of times T, , T w in the circuit system, the circuit to check the time relationship between the two only needs to have a simple divisor circuit, and the signal Since the data storage method can be determined in advance, the signal memory circuit can also be simplified.

Here, if total<Tr and T are not in an integer ratio, the algorithm for determining how many lines to write into memory in which frame is extremely complex, and it is nearly impossible to realize it with circuits alone. In this case, it is necessary to take the help of software such as a microcomputer, which can be achieved.

Therefore, in the above embodiment, the case where the recording time coincides with the paper feeding time has been described, but an example in which the recording time does not match, that is, the recording ends within the paper feeding time, is as follows. This will be explained next.

That is, even if the recording time is arbitrary, the total recording time can be similarly shortened by adding a little free time to the recording time and satisfying the condition of n/m times the previous recording time.

Here, FIG. 4 shows the time and recording of one frame of a video signal according to another embodiment of the present invention when formula (1) is satisfied by adding a little idle time to the recording time. FIG. 3 is an explanatory diagram that also shows the temporal relationship with time.

That is, the paper feeding time T is the sum of the idle time Δt and the net recording time TW', so that the above equation (1) is satisfied.

If such a method is used, the same effects as the previous embodiment can be expected.

Although each of the above-mentioned embodiments relates to the (1) frame, it can also be implemented in exactly the same manner in the case of one field.

〔Effect of the invention〕

According to the present invention, it is possible to provide a video signal printing method that has a simple configuration and can record in a short time.

[Brief explanation of the drawing]

(A) and (B) of FIG. 1 are explanatory diagrams of the temporal relationship between the time of one frame of a video signal and the recording time. FIG. An explanatory diagram that also shows the temporal relationship between the time of one frame and the recording time, FIG. 3 is a synchronous partial configuration diagram of a video printer used for implementing the same, and FIG. 4 is a diagram showing another embodiment of the present invention. FIG. 2 is an explanatory diagram showing the temporal relationship between the time of one frame of such a video signal and the recording time. 1... Video synchronization separation circuit, 2A, 2B... Frequency multiplier, 3... Frequency comparator, 4... Paper feed 9 drums, 5... DC motor, 6... Rotation speed detection disc,
7... Rotation speed detection sensor, 8... Motor control device. (1 other person) 1. Chopsticks to ゜゜゜゜゜ゝ゜゜゜゜゜゜゜ゞ゜口

Claims (1)

[Claims] 1. In a video printer that records video signals one line at a time horizontally or vertically, a plurality of lines can be read horizontally or vertically in an image within one field or one frame of the video signal. At the same time as the above time +
17m (II, In is an integer, and a video signal printing method is characterized in that one line is recorded in n (m) times the time and the paper is fed. 2. Claim 1) In this system, a DC motor is used to drive the paper feed of recorded recording paper, and a rotation speed sensor is used to detect the rotation speed, and the frequency of one field or one frame of the video signal and the rotation speed of the DC motor are A video signal printing method that allows the same Jυノ.