JPH0817477B2 - Image information conversion device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Table of Contents] Outline Industrial field of application Conventional technology (Figs. 5 and 6) Problem to be solved by the invention Means for solving the problem (Fig. 1) Operation Example (FIGS. 2 to 4) Effects of the Invention [Overview] Image information conversion apparatus, in particular, image information synchronized with the first clock is written alternately in the memory, and image information synchronized with the second clock is alternated in the memory. A device for performing read-out processing, the generation of a discontinuous portion of read-out image information caused by the time difference between the first and second clocks without forcibly switching the operation during write / read-out processing of the memory. The present invention comprises two or more storage means, a selection means, and a control means for the purpose of eliminating the error and performing the conversion processing of the image information with high accuracy, and the input image information is selected based on the first reference signal. One storage means A writing / reading device for writing and reading output image information from the other storage means selected based on the second reference signal, wherein a new image is stored in the storage means until all image information in one storage means is read out. It is configured including the provision of write / read control auxiliary means for prohibiting the writing of information.

[Industrial applications]

The present invention relates to an image information conversion device, and more specifically, it writes image information synchronized with a first clock alternately in memory, and reads image information synchronized with a second clock from alternate memory. It relates to the device.

In recent years, with the progress of digital signal processing technology, so-called high-definition television has been developed, which aims to significantly improve the image quality of television images by converting a composite image signal into an analog / digital signal and digitizing the image signal processing. ing.

Thereby, for example, when the composite video data written by the vertical sync signal synchronized with the first scanning system is read out in synchronization with the vertical sync signal of the second scanning system, the writing / writing There is a demand for an image information apparatus capable of eliminating a discontinuous portion due to a time difference in reading processing.

[Conventional technology]

 5 and 6 are explanatory views according to the conventional example.

FIG. 5 is a block diagram of a conventional image information conversion device.

In the figure, the image information conversion device for writing / reading the two systems of memories X and Y alternately is a video signal of the scanning system A.
Memory (X) 1 for storing DIN, memory (Y) 2, demultiplex circuits 3a, 3d for selecting write / read processing for memories X, Y, and write / read addresses for memory X, Y are selected. Multiplex circuits 3b and 3c, a write pulse generation circuit 4a that generates a write control signal φ1, a read pulse generation circuit 4b that generates a read control signal φ2,
It is composed of a JK-FF circuit 5 for controlling write / read processing of the memories X and Y, and address counters 6 and 7.

Further, the apparatus writes the video signal DIN of the scanning system A for one screen of the television in the memory X or Y based on the writing control signal φ1 synchronized with the scanning system A, for example.
The video signal A of the scanning system A is converted into the video signal DOT of the scanning system B by reading the video signal previously written from the memory Y or X based on the read control signal φ2 synchronized with the scanning system B. To do.

The writing process of the memories X and Y is performed based on the vertical synchronizing signal Vsync (W) of the scanning system A, and the reading process thereof is performed based on the vertical synchronizing signal Vsync (R) of the scanning system B.

[Problems to be Solved by the Invention]

FIGS. 6A to 6C are explanatory diagrams related to the problems of the conventional image information conversion apparatus. In FIG. 6A, the vertical synchronization signal Vsync (W) of the scanning system A is of the scanning system B. Vertical sync signal Vsync
The operation time chart concerning the device when it is lower than (R) is shown.

In the same figure (a), the vertical synchronization signal Vsync of the scanning system A
In synchronization with (W), the video signal DIN of the scanning system A is transferred to the memories X and Y.
Is written to. a, c, e, g ... Show write data for the video signal DIN of the scanning system A to the memory X, and similarly (a), (c), (e), (g) ... The read data is shown. Further, b, d, f, ... Are the scanning system A
Shows the write data of the video signal DIN to the memory Y, and similarly (b), (d), (f) ... Shows the read data.

As a result, the video signal DOT of the scanning system B synchronized with the vertical synchronization signal Vsync (R) of the scanning system B is read data (a), (a) + (a), (a) from the memories X and Y. +
(B), (b) + (c), (c), (d) + (e),
(E) + (f), (f) ... At this time,
(A) + (a), (a) + (b), (b) + (c),
(C) + (d), (d) + (e) and (e) + (f)
A discontinuous portion 8 is generated in the read data.

FIG. 3B shows a diagram relating to a scan image for explaining the discontinuous portion 8.

In FIG. 6B, the circles and the circles are the data for one pixel, the data related to the writing / reading processing of the memory X are shown as the circles, and the data related to the writing / reading processing of the memory Y is indicated. It is shown as a circle. According to this, the discontinuous portion 8 relates to the video data (a) of the fourth pixel when the reading process of the video data (a) of the third pixel of one horizontal scanning line from the memory Y is not completed, for example. This occurs at the boundary between the read data (a) and the read data (a) because the read process from the memory X is started. This is due to the read time difference caused by the phase difference between the vertical sync signal Vsync (W) of the scan A and the vertical sync signal Vsync (R) of the scan system B. This is also memory X
Writing to the memory X → Y when the writing process to the memory X is finished, or to the reading process to the memory X → Y when the reading process from the memory Y is finished. This occurs because the write / read process is forcibly switched even if the process or read process is in progress.

Therefore, the discontinuous portion 8 is the read data (a) (b).
, (B) (c), (c) (d), (d) (e)
, (E), (f), ...

FIG. 6C shows a state in which the scanning signal including the discontinuous portion 8 is displayed on the screen.

In FIG. 2C, reference numeral 10 denotes a position shift screen, which is generated when the screen of the CRT device 9 is horizontally scanned by a scanning signal including a discontinuous portion.

In this way, the vertical synchronization signal Vsync of the scanning system A is
The video signal DIN processed based on (W) is supplied to the scanning system B.
When converting to the video signal DOT of the scanning system B synchronized with the vertical synchronization signal Vsync (R) of
Due to the time difference of (R), the discontinuous portion 8 as shown in FIG. 9A may be included in the video signal DOT of the scanning system B.

As a result, the displacement screen 10 as shown in FIG. 6C is generated, and there is a problem that the image information cannot be converted accurately.

The present invention was created in view of the above conventional problems, and causes the time difference between the first and second clocks without forcibly switching the operation during the memory write / read processing. It is an object of the present invention to provide an image information conversion device capable of performing accurate conversion of image information by eliminating the occurrence of a discontinuous portion of the read image information that occurs.

[Means for solving the problem]

FIG. 1 shows a principle diagram relating to the image information conversion apparatus of the present invention.

The device comprises two or more storage means 11, 12, ..., Selection means 13, and control means 14 for input image information DIN,
A writing / reading device for writing to one storage means 11 selected based on the first reference signal φ1 and reading output image information DOT from the other storage means 12 selected based on the second reference signal φ2. One storage means (11,12 ...
.. Writing / prohibiting writing of new image information in the storage means until all image information
A read control assisting means 15 is provided to achieve the above object.

[Action]

According to the present invention, a write / read control assisting means 15 is provided for assisting the write / read control of the control means 14.

For this reason, one of the storage means 12 selected based on the second reference signal φ2 is selected based on the first reference signal φ1 while the output image information DOT is being read. Even when the storage unit 11 finishes the writing process of the input image information DIN, the writing / reading control assisting unit 15 performs the reading process of the storage unit 12 for the next reading process of the storage unit 11 that has finished the writing process. Until the end, the operation function of the storage means 11 can be restricted.

As a result, the first and second reference signals φ1,
It is possible to eliminate the occurrence of the discontinuous portion of the read image information due to the time difference of φ2. Therefore, it is possible to perform an accurate conversion process of image information.

〔Example〕

Next, an embodiment of the present invention will be described with reference to the drawings.

2 to 4 are diagrams for explaining the image information conversion apparatus according to the embodiment of the present invention, and FIG. 2 is a configuration diagram of the image information conversion apparatus according to the embodiment of the present invention.

In the embodiment of the present invention, the writing / reading processing of the video signal DIN of the scanning system A is alternately performed by using the two systems of memories X and Y to perform image conversion into the video signal DOT of the scanning system B. The image information conversion device will be described.

In the figure, reference numeral 21 denotes a memory X which is an embodiment of the first storage means, and performs a writing process of the video signal DIN of the scanning system A based on the vertical synchronization signal Vsync (W) of the scanning system A, In synchronization with the vertical synchronization signal Vsync (R) of the scanning system B,
The video signal is read out and processed as the video signal DOT of the scanning system B. Reference numeral 22 is a memory Y which is an embodiment of the second storage means and has the same operation function as the memory X.

Denoted at 23a to 23e are demultiplexing circuits as an example of the selecting means 13. They are a multiplex circuit, a write pulse generation circuit, and a read pulse generation circuit. The demultiplex circuit 23a receives the write pulse signal S1 based on the switching control signal S3 from the write / read control auxiliary circuit.
Is selectively output to the memory X as a write signal WRX or to the memory Y as a write signal WRY. Similarly, the multiplex circuits 23b and 23c select the write address Add (W) or the read address Add (R) based on the switching control signal S3 and output it to the memory X or the memory.

Similarly, the demultiplexing circuit 23d selectively outputs the read pulse signal S2 to the memory X as the read signal RDX or to the memory Y as the read signal RDY based on the switching control signal S3. Write pulse generation circuit 23
d is a signal for generating the write pulse signal S1, and its output is controlled based on the write inhibit signal S4. For example, the output of the write pulse signal S1 is turned off when the disable terminal ▲ ▼ becomes "L" level. The read pulse generation circuit 23e is for generating the read pulse signal S2.

Reference numerals 25a and 25b are a write control auxiliary circuit and a read control auxiliary circuit which are one embodiment of the write / read control auxiliary means 15. The write control auxiliary circuit 25a includes an AND circuit 51, a JK-FF circuit 24c, an XOR circuit 52, and a latch circuit 56. The write control signal S6 is input from the address counter 24a, and the write inhibit signal S4, the switching control signal S3 and The switching signal S5 is output.

The read control auxiliary circuit 25b includes an XOR circuit 53 and a JK-FF circuit 54
And an AND circuit 55, which receives the read control signal S7 from the address counter 24b and the switching signal S5 from the write control auxiliary circuit 25a and outputs the switching control signal S3.

Reference numerals 24a and 24b are address counters which are an example of the control means 14 and which mainly control write / read processing of the memories X and Y. The address counter 24a is a scanning system A
The vertical synchronizing signal Vsync (W) is input and the write control signal S6 is output to the write control auxiliary circuit 25a, and the write address Add (W) is output to the multiplex circuits 23b and 23c.

As a result, the two memories X and Y according to the embodiment of the present invention are
An image information conversion device using is constructed.

 Next, the operation of the device will be described.

FIG. 3 is an operation time chart (when VF is high) according to the image information conversion apparatus of the first embodiment of the present invention, in which the vertical synchronization signal Vsync (W) of the scanning system A is the vertical synchronization of the scanning system B. The case where the frequency is lower than the frequency VF of the signal Vsync (R) is shown.

In the figure, first, the memory X is the video signal DIN of the scanning system A.
Data a related to the scanning system B
It is assumed that the data (a) relating to the video signal DOT is read out. At this time, the multiplex circuit 2 to which the write address Add (W) of the address counter 24a is input
3b specifies the write address Add (W) in the memory X,
The multiplexer circuit 23c to which the address Add (R) of the address counter 24b is input is read out by the read address Add to the memory Y.
(R) is designated.

Next, when the writing process of the data a relating to the video signal DINN of the scanning system A to the memory Y is completed, the address counter 24
a and 24e have vertical sync signals Vsync (W),
Count up based on (R). As a result, the multiplex circuits 23b, 23b specify the read address Add (R) in the memory X and the write address Add in the memory Y.
Specify (W). However, since the reading process of the memory Y is not completed, the write control auxiliary circuit 25a outputs the write inhibit signal S4 to the write pulse generating circuit 23d. This eliminates the situation where the memory X is forcibly switched from the writing process to the reading process during the reading process of the memory Y as in the conventional example.

The detection of the end of the reading process of the memory Y is performed by the JK-FF circuit 54 of the read control auxiliary circuit 25b to which the read control signal S7 and the switching control signal S3 are input, and the detection result is used as the switching control signal S3. Prek circuit 23a, 23
It is output to d and the multiplex circuits 23b and 23c. On the other hand, in the write control auxiliary circuit 25a, one carry of the JK-FF circuit 24c is input, its logic is inverted, and the carry is taken into the latch circuit 56 in synchronization with Vsync (W) input next. , Becomes "H" level, and the write protection is released.

As a result, the reading process of the data (a) related to the video signal DOT of the scanning system A from the memory X is started, and the writing process of the video signal DIN of the scanning system B to the memory Y is performed by the next Vsync.
The data c starts from (W).

At this time, in the state of the memories X and Y, B is written,
A standby state in which neither read processing is performed is shown, and A indicates a state in which only write processing is not performed. Therefore, the write data related to the video signal DIN of the scanning system A of the memory X becomes a, e, h ... And the read data related to the video signal DOT of the scanning system B is (a), (e), (H) ... Further, the write data relating to the video signal DIN of the scanning system A of the memory Y is c, g, j ... And the read data relating to the video signal of the scanning system B is (a), (c),
(G), (j) ...

As a result, the data relating to the video signal DOT of the scanning system B read from the memories X and Y are (a),
(A), (a), (a), (c), (c), (c),
(E), (e), (g), (g), (h) ... Therefore, it is possible to eliminate the situation where read data includes a discontinuous portion as in the conventional example.

FIG. 4 is a time chart of the operation (when VF is low) of the image information conversion apparatus according to the embodiment of the present invention.

In the figure, the difference from the first embodiment is that in the second embodiment, the frequency of the vertical synchronizing signal Vsync (W) of the scanning system A is higher than the frequency VF of the vertical synchronizing signal Vsync (R) of the scanning system b. It is expensive.

Therefore, the configuration of the device is the same as that of the first embodiment, and the description thereof is omitted.

Also in this case, as in the first embodiment, the memory X writes the data a relating to the video signal DIN of the scanning system A and the memory Y reads the data (a) relating to the video signal DOT of the scanning system B. Assuming that the memory X is performing the processing, it waits for the completion of the reading processing of the memory Y even if the memory X has completed the writing processing first. Then, following the end of the reading process, the memory X shifts to the reading process of the data (a) related to the video signal DOT of the scanning system B.

As a result, the frequency of the vertical synchronization signal Vsync (W) of the scanning system A is the frequency V of the vertical synchronization signal Vsync (R) of the scanning system B.
Even when it is higher than F, it is possible to eliminate the discontinuous portion 8 in the read data as in the prior art, as in the first embodiment.

In this way, the write control auxiliary circuit 25a and the XOR circuit 5 including the AND circuit 51, the XOR circuit 52 and the like for assisting the write / read control of the address counters 24a, 24b and the JK-FF circuit 24c.
3, Read control auxiliary circuit consisting of JK-FF circuit 54 and AND circuit 55
25b is provided.

Therefore, while the memory Y selected based on the vertical synchronization signal Vsync (R) of the scanning system B is reading the video signal DOT of the scanning system B, the vertical synchronization signal Vsync (W Even if the memory X selected based on the above) completes the writing process of the video signal DIN of the scanning system A, the memory for which the writing control auxiliary circuit 25a has finished the writing process prior to the reading process of the memory Y. Regarding the next read processing of X, the read processing operation function of the memory X can be restricted by outputting the write inhibit signal S4 to the write pulse generation circuit until the end of the read processing of the memory Y. Becomes

As a result, it is possible to eliminate the occurrence of the discontinuous portion of the read data caused by the time difference between the vertical synchronizing signals Vsync (W) and (R) of the scanning systems A and B as in the conventional example.

Therefore, since it is possible to perform the conversion processing of the image information with high accuracy, it is possible to suppress the occurrence of the displacement screen information as in the conventional example as much as possible.

In the embodiment of the present invention, the writing / reading process of the video signals for two screens by the two systems of the memories X, Y has been described.
It may be configured by three or more systems. At this time, JK-
A counter or the like is used instead of the FF circuits 24c and 54, and the XOR circuits 52, 5
By using a comparator or the like instead of 3, the same effect can be obtained.

〔The invention's effect〕

As described above, according to the present invention, the writing / reading control assisting means does not forcibly switch the processing operation during the writing / reading processing of the memory as in the conventional case, and the first and second scanning systems are provided. It is possible to eliminate the occurrence of the discontinuous portion of the read image information which is caused by the time difference of the reference signal.

As a result, it is possible to perform an accurate conversion process of image information between different scanning systems.

[Brief description of drawings]

FIG. 1 is a principle diagram of the image information conversion apparatus of the present invention, FIG. 2 is a configuration diagram of the image information conversion apparatus of the first embodiment of the present invention, and FIG. 3 is a first diagram of the present invention. FIG. 4 is an operation time chart (when VF is low) related to the image information conversion apparatus according to the second embodiment of the present invention. FIG. 5 is a configuration diagram of a conventional image information conversion device, and FIGS. 6A to 6C are explanatory diagrams relating to problems of the conventional image information conversion device. (Explanation of symbols) 11, ... First storage means, 12 ... Second storage means, 13 ... Selection means, 14 ... Control means, 15 ... Write / read control auxiliary means, φ1 ... 1 reference signal, φ2: second reference signal, DIN: input image information, DOT: output image information.

Claims (1)

[Claims] 1. A storage device comprising two or more storage means (11, 12, ...), a selection means (13) and a control means (14) for input image information (DIN) as a first reference signal. Write to one storage means (11) selected based on (φ1) and read output image information (DOT) from the other storage means (12) selected based on the second reference signal (φ2). A writing / reading device, which is a writing / reading control for prohibiting writing of new image information in one storage means (any one of 11, 12 ...) Until the entire image information is read. An image information conversion apparatus, characterized in that auxiliary means (15) is provided.