JPS6324351B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to, for example, video special effects, and relates to an image processing device that obtains an image composed of rectangular pixels (mosaic) from a digitally converted video signal.

Conventionally, in order to obtain a mosaic image made up of square pixels as a video special effect, a common method is to prepare a cost made up of square pixels and image it with a television camera. In order to turn this image into a moving image that moves in real time, it is necessary to process each frame one by one as in the production of so-called animation, which requires a lot of man-hours and costs. Also,
Because the types of original images are limited, it is not possible to create mosaic images from ordinary photographs or materials as seen with a camera, and there are significant limitations in terms of materials. moreover,
The size of the mosaic unit of the mosaic image is determined by the original image, so it is difficult to compose complex patterns.
It tends to be a repeating pattern,
There is little change. Moreover, in the case of creating a moving image, the above-described method has the problem that the changes in the image cannot be seen until the image is completed, which often results in unintended results and that the interest as a special effect is lost.

This invention has been made based on the above circumstances, and it reads out image data stored in an image storage section in synchronization with the scanning timing of a television screen, and reconstructs the read out image data to create a mosaic material. , which aims to remove the constraints on the size of the mosaic unit and the constraints on making it into a moving image, and to obtain a practical mosaic special effect.In particular, when playing back a mosaic image, the writing operation is performed once every four fields. By doing so,
The present invention aims to provide an image processing device that can obtain stable mosaic images without flickering.

An embodiment of the present invention will be described below with reference to the drawings.

First, the outline of the device will be explained. In FIG. 1, a video input signal V ₁ is supplied to an A/D (analog/digital) converter 11 . This A/D
The converter 11 has a horizontal synchronization pulse period of 52 μs in the 63.5 μs period.
The sampling period is set to 93 ns so that about ₁₉₂ cycles of the color subcarrier contained in converted into a signal. Therefore, there are 576 sampling points per scanning line, giving 576 pieces of image data.
Hereinafter, one image data will be referred to as one dot. The output signal of this A/D converter 11 is supplied to an S/P (serial/parallel) converter 12. This S/P converter 12 performs serial/parallel conversion for 3 cycles of color subcarriers, that is, 9 dots at a time, and the conversion output of this S/P converter 12 is converted into 3 cycles according to the control of the write controller 13. One cycle is addressed and stored in the image storage section 14. This image storage section 14 has a storage capacity for one field, for example, and the S/P conversion section 1
The output of 2 is stored as shown in FIG. In Figure 2, H is the horizontal direction and V is the vertical direction, including the blanking period in the V direction.
242 addresses are set. When image data is read from the image storage section 14, it is done in accordance with address data stored in the address control section 15. This read data is supplied to a P/S (parallel/serial) converter 16. This P/S conversion section 16 is the image storage section 1
This is a buffer section for timing adjustment between the S/P converter 12 and the subsequent stage, and, like the S/P converter 12, the number of dots that can be processed at one time is, for example, 9 dots. The conversion output of this P/S converter 16 is supplied to a D/A (digital/analog) converter 17,
The A converter 17 outputs an analog-converted video signal. Note that the image data in the image storage section 14 is not lost when read out once, but is retained for at least one field time.

On the other hand, in order to obtain a mosaic image, the screen is divided into, for example, a plurality of mosaic units, and each mosaic unit is configured with predetermined representative data. Figure 3 explains address conversion to obtain a mosaic image, where x and y indicate the size of one unit of mosaic in the horizontal direction H and vertical direction V, respectively. In this case, x = 7, y =5.
One point of representative data is selected for each mosaic unit determined to have this size. For example, if the central part of a mosaic unit is the representative data, the mosaic unit
The representative data for _M1 is the dot (H4, V3). Now, if the readout scan of the image storage unit 14 comes within the mosaic unit _M1 , then the representative data (H
4, V3) and successively extract representative data (H4, V3) from this, the mosaic unit M ₁
can all be converted into representative data (H4, V3). That is, when the address control unit 15 reads out and scans the inside of the mosaic unit _M1 , only the V3 line is addressed, and the P/S is determined from the read image data of the V3 line.
The converter 16 may continuously extract only the representative data (H4, V3) under the control of the data controller 18. By converting each mosaic unit in this manner, it is possible to obtain a mosaiced video output signal V ₂ corresponding to the video input signal V ₁ . The address control section 15 and data control section 18 are controlled by a mosaic control section 19, and the values of the sizes x and y of the mosaic unit are given by this mosaic control device 19.

Next, each part will be further explained. First, how to define representative data will be explained.

Various methods can be considered for determining representative data constituting a mosaic unit, but when representative data is determined on the boundary line of a mosaic unit, various drawbacks occur. In other words, there is a possibility that the data obtained by sampling the blanking level (point B) in the video signal shown in Figure 4a becomes representative data, and in this case, unnecessary black pixels will appear in the reconstructed mosaic screen. . FIG. 4b shows this. When point B in FIG. 4a is representative data, at least the oblique part becomes a black pixel. This black pixel is not noticeable when the mosaic unit is small, but when it is made large, the black pixel area is expanded, and when one screen is composed of one pixel (one representative data), it is always a black pixel. Therefore, in the present application, the representative data is set at a position other than the boundary line of each mosaic unit to prevent the above-mentioned inconvenience. Note that this representative data is stored in the address control section 15,
It is set in advance by the data control unit 18.

Next, write control of the image storage section 14 will be explained.

Access to the image storage section 14 on the writing side and access on the reading side are performed alternately.
Therefore, all data in the image storage section 14 is rewritten within a unit time specific to the device. This is no exception to the representative data of each mosaic unit. For this reason, in FIG. ₃ , representative data (H4,
V3) may be rewritten midway through.
In this case, two pieces of representative data exist within one reconstructed mosaic unit, and a boundary (horizontal line) occurs within one mosaic unit. This phenomenon is not noticeable when the values of the mosaic unit x and y are small, but when the values of x and y are large, the boundary becomes clear, and the screen becomes like this, where each mosaic unit is divided into two vertically and vertically by the boundary. As a result, data changes are accompanied by a so-called flickering phenomenon, resulting in an unsightly screen.
FIG. 5 explains this, and shows a case where there is a difference of 1H (one V line) between the write side scan and the read side scan, and the read side takes the lead. Here, in the mosaic unit M ₁ , if the representative data (H4, V3) before writing is M _1-1 and after writing is M _1-2 , then the upper half of the boundary dividing the mosaic unit into two (indicated by the dotted line) The data _M1-1 before writing is read, and the data after one line (H
4, V4), the rewritten data _M1-2 is read out. This is extremely unsightly as it also occurs in other mosaic units.

For this reason, the image storage section 14 has a configuration shown in FIG. 6. That is, 14a and 14b are storage sections each having a storage capacity for one field, and the duplicated storage sections 14a and 14b are provided with an input changeover switch 14c and an output changeover switch 14d. This switch 14
c and 14d alternately store the storage units 14a and 14, respectively.
b can be selected by switching. Therefore, the storage section that is being written can be made write-only;
Since the storage section being read out can be made read-only, the above-mentioned inconvenience does not occur, and one mosaic unit is composed only of the relevant representative data.

Next, the representative data will be further explained. The representative data mentioned above is composed of one dot. Therefore, if the representative data is affected by noise, it will immediately appear in the mosaic and be difficult to see. This is not so much of a problem when the mosaic unit is small, but when the mosaic unit becomes large, the pixel area is also enlarged, so the effect is magnified, which is inconvenient. Therefore, in practice, a plurality of dots are selected within one mosaic unit, the average value of the data values of each dot is determined, and this is used as representative data of the corresponding mosaic unit. Figure 7 shows an example.
Adjacent (H4, V2), (H3, V3), (H4,
This is a case where five dots, V3), (H5, V3), and (H4, V4) are selected. At this time, if the data values of each dot are A, B, C, D, and E, then the representative data of this mosaic unit is (A+B+C+D
+E)/5. In order to obtain the average value of a plurality of dots in this way, the P/S conversion section 16 and the D/A
A data averaging circuit may be provided between the converter 17 and the converter 17. By averaging a plurality of dots to obtain representative data in this way, it is possible to suppress the influence of noise.

Next, a case will be described in which the sizes x and y of the mosaic unit are arbitrarily changed. Here, the address control section 15, data control section 18, and mosaic control section 19 will be further explained.

The mosaic control section 19 specifies the size of a mosaic unit using, for example, a digital signal of 1 to 31, and the output signal of this mosaic control section 19 is supplied to the address control section 15 and the data control section 18. This address control unit 15 has horizontal direction H and vertical direction V corresponding to the size of the mosaic unit.
Each of them is provided with 1 to 31 storage units, such as PROM (programmable read-only memory). Of these PROMs, those corresponding to the horizontal direction H are, for example, 1 as shown in Figure 8a.
It has a ~64 address configuration. This is because, as described above, the access unit of the image storage unit 14 is three cycles of the color subcarrier, and is defined by the relationship: 576 dots/9 dots=64 dots. Also, in the PROM, vertical direction V
As shown in FIG. 8b, the addresses corresponding to , respectively, have, for example, 1 to 242 addresses. This matches the address structure of the image storage section 14. And PROM in horizontal direction H and vertical direction V
Each has an image storage unit 1 corresponding to the mosaic unit.
4 access address data are stored in advance.

Further, the data control unit 18 is provided with 1 to 31 storage units, such as PROM, corresponding to the size of the mosaic unit. As shown in Figure 9, this PROM corresponds to the number of dots in the horizontal direction.
It has a configuration of 576 addresses, and control data for configuring one mosaic unit with the minimum representative data (for example, 3 dots) is stored in advance.

Accordingly, the address control section 15 and the data control section 18 select corresponding PROMs according to the output signals of the mosaic control section 19, respectively.
That is, for example, if the output signal of the mosaic control section 19 is "1", PROM1 of the address control section 15 and the data control section 18 is selected. and,
The address control section 15 accesses the image storage section 14 using the data stored in the selected PROM, and the data control section 18 controls the P/S conversion section 16 according to the data stored in the PROM.

The operation in the above configuration will be explained. Now, it is assumed that the digital signal "1" is output as the output signal of the mosaic control section 19, and in this case, the mosaic unit is x=7 dots as shown in FIG.
It is assumed that y=5 dots. Furthermore, the number of dots that can be processed at one time by the P/S converter 16 is P=9 dots, and in FIG. 10, P ₁ ,
P ₂ , P ₃ , . . . indicate the order of P/S conversion. In this state, first, PROM1 is selected in each of the address control section 15 and the data control section 18 by the output signal of the mosaic control section 19. PROM1 includes, for example, Figure 8 a, b, 9
Address data shown in the figure is stored, and this data is accessed according to each scan timing. Then, the image storage section 14 is read out according to the data stored in the PROM 1 of the address control section 15. That is, when the scanning timing is, for example, mosaic unit _M1 , the image data of the _P1 portion (H1, V3) to (H9, V3) shown in FIG. 10 is read out and supplied to the P/S converter 16. . The P/S converter 16 is provided with a plurality of buffer registers 16a ₁ to 16an as shown in FIG. 11, and the read image data is distributed by a distributor 16b. For example, it is supplied to the register _16a1 by the timing pulse _PL . From this register 16a ₁ , the selection circuit 16
Representative data is repeatedly extracted by c.
This selection circuit 16c is controlled by the output signal _PR of the data control section 18. That is, the registers 16a ₁ to 16an and the selection circuit 16c are arranged as shown in FIG. 12. Note that FIG. 12 shows a part of FIG. 11. In this figure, register _16a1 is a so-called circular shift register, and data in 16d is circularly shifted to 16e. This register _16a1 sequentially holds the data corresponding to the H direction of the V3 line. In order to extract the representative data corresponding to the scanning of the mosaic unit _M1 , the switch 16g of the selection circuit 16c is first turned on. Therefore, the data of H4, H5, and H6 are taken out from the switch 16g according to the shift operation, and then the switches 16f and 16h are sequentially turned on, so that the representative data (H4, V3), (H5 ,V
3), (H6, V3) is extracted and the mosaic unit
(H1, V1) to (H7, V1) of _M1 are converted to representative data.

Next, when the scanning moves to the mosaic unit _M2 , the image data of the _P1 portion is stored in the register _16a2 while the image data of the _{P1 portion} (H10, V3) to (H18) shown in FIG. , V3) is read out. Then, from the register _16a2 , representative data ( _H11 , V3), (H1
2, V3) and (H13, V3) are repeatedly read out, and ( _H8 , V1) to (H1
5, V1) is converted into the representative data. Thereafter, such operations are sequentially performed to convert each mosaic unit into corresponding representative data.

Next, it is assumed that a signal "n" is output from the mosaic control circuit 19, and the mosaic unit at this time is, for example, x=11 and y=7 as shown by the dotted line in FIG. In this state, first, if the scanning timing is mosaic unit M ₁ , representative data of P ₁ part (H5, V4), (H6, V4), (H7, V4)
The image data of (H1, V4) to (H9, V4) including the above are read out and supplied to the register _16a1 . From this register _16a1 , the operation of the selection circuit 16c described above is controlled by the data control section 18.
This is performed according to the data of PROMn, and (H1, V1) to (H9, V1) of mosaic unit _M1 are converted into representative data. In this state, the image storage unit 14 outputs the _P2 portion, that is, (H10, V4) to
(H18, V4) is read out and held in the register _16a2 . Then, ( _H1
0, V1), (H11, V1) are converted to representative data held in register _16a1 , and are divided into mosaic units.
(H12, V1) to (H18, V1) of M ₂ are representative data (H16, V4), (H17, V4), (H
18, V4). In this state, the _P3 portion is read out from the image storage section 14, and this image data is held in the register _16a1 or _16a3 . Then, the mosaic unit M ₂ (H19,
V1) to (H22, V1) are the registers 16a ₂
is converted into representative data held in . Thereafter, such operations are performed for each mosaic unit, and each mosaic unit is converted into corresponding representative data. Note that the number of registers is actually 2 to 2.
Three registers can cover most sizes of mosaic units, and the data control unit 18 takes out data from these registers as appropriate.

As described above, by providing a plurality of registers in the present application, the size of the mosaic unit can be determined regardless of the number of data P that the P/S converter 16 can process at once. That is, for example, when there is one register, the constraint condition holds between P and the mosaic unit x in the H direction that when P>x, P/x=integer, and when P<x, x/P=integer. do. Therefore, if the mosaic units described above are x = 11 dots and y = 7 dots, when scanning H10 and H11 of mosaic unit _M1 , they will be converted to representative data of mosaic unit _M2 , This makes it impossible to freely vary the size of the mosaic unit. Therefore, as described above, in the present application, a plurality of registers are provided to make the size of the mosaic unit variable without being restricted by the number P of data that the P/S converter 16 can process at one time.

Next, the mosaic control section 19 will be further explained. As described above, the mosaic control section 19 selects and controls the size of the mosaic unit. In order to make a mosaic image highly practical as a special effect, it is desired that the size of the mosaic unit can be easily varied. Therefore, it is conceivable to use, for example, a fader and use the position information of the fader for this control.

FIG. 13 shows an example of this, in which position information of the fader 20 is supplied to the mosaic control section 19. This position information is A/D converted in the mosaic control section 19, and the digital signals "1" to "31" described above are generated.
Therefore, “1” depending on the position of the feeder 20.
~ “31” digital signal is sent to mosaic control unit 19
The signal is then supplied to the address control section 15 and data control section 18, and these control sections 15 and 18 select PROM1 to PROM31 corresponding to the digital signal. A mosaic image is then generated using the data stored in this PROM.

Further, by using the fader 20, it is possible to obtain various special effects. For example, the screen
When converting the screen from P _A to screen P _B , first, the screen P _A that is not subjected to mosaic conversion is displayed, and in this state, the fader 20 is operated to convert the screen P _A into, for example, the smallest mosaic image. Then, operate the fader 20 to gradually increase the size of this mosaic unit, and display the screen at the maximum mosaic unit.
Switch from P _A to P _B. At this time, screen P _B is the largest mosaic unit. From this state, the fader 20 is further operated to gradually make the mosaic unit smaller, and finally an image P _B that is not subjected to mosaic conversion is obtained.

In this way, by varying the size of the mosaic unit using the fader 20, it is possible to obtain a wide variety of special effects. In FIG. 13, the same parts as in FIG. 1 are given the same reference numerals.

Next, the write control section 13 will be further explained.

When generating a mosaic image, it is desirable that the representative data have values as stable as possible. For example, when converting a still image or an image similar to a still image with little movement into a mosaic image, even if the values of the representative data differ even slightly, the image will flicker on the playback screen because the pixels are larger. This is due to the nature of the NTSC system. That is, in the NTSC system, the frequency of the color subcarrier is an odd multiple (455/2 times) of 1/2 the line frequency. Therefore, the phase of the color subcarrier for each line differs by 180°. Furthermore, since the number of lines in each frame is 525, which is a parsimonious number, the phases of the color subcarriers at the starting points of consecutive frames also differ by 180°. Therefore, the color subcarriers are in phase once every four fields. FIG. 14 shows the movement of sample points caused by the four-field sequence of the NTSC system, and shows that the writing start point (arrow in the figure) differs from field to field. Figure 15 is the 14th
3 shows the movement of pixel data content derived from the figure. As is clear from the figure, even data on the same line has different contents for each field. For example, the data of line number 1 in frame 1 and the data of line number 246 in a different field have a horizontal position shift of 140 ns and a vertical position shift of 1/2 line. This relationship is the same for frame 2, and considering the 4-field sequence, the first
The data contents will move as shown by the arrows in Figure 5. Therefore, the same data can only be obtained once every four fields. For this reason, in mosaic conversion of a signal close to a still image, using data that is updated every field will result in an image with a lot of flickering, which is inconvenient.

Therefore, in this application, the writing cycle is changed so as to be compatible with still images. That is, when obtaining a mosaic image, writing is performed once in four fields. This switching control is performed, for example, by a control signal supplied from the mosaic control section 19 to the write control section 13. In this way, a flicker-free mosaic image can be obtained even in mosaic conversion of a still image or an image close to a still image.

According to the above configuration, the video input signal V ₁ is digitally converted and stored in the image storage section 14, and in the process of reading out this stored data, it is reconfigured according to the stored data of the address conversion section 18 and the data control section 19, and is mosaiced. Generating images. Therefore, it is possible to convert any image, whether it is a moving image or a still image, into a mosaic image, and the number of man-hours required for this conversion is extremely small compared to the conventional method. Furthermore, since this mosaic conversion is instantaneous, it is possible to immediately see how the image changes, which is extremely useful for obtaining special video effects.

Further, the representative data constituting the mosaic unit is set, for example, at the center, which is spaced apart from the boundary of the mosaic unit. Therefore, unnecessary black pixels do not appear in the generated mosaic image, which is convenient.

Further, since the representative data is an average value of a plurality of pixels, there is an advantage that even if noise is mixed in the pixels, the influence of noise is reduced and image quality deterioration can be suppressed.

Further, the image storage unit 14 is the same storage unit 14a,
14b is provided, which is connected to the input selector switch 14.
c. By alternately switching with the output changeover switch 14d, the storage sections 14a and 14b are made write-only and read-only, respectively. Therefore, since no data is written to the storage unit that is in the read state, one mosaic unit is
Inconveniences caused by individual representative data can be prevented, and a flicker-free mosaic image can be obtained.

Further, the P/S converter 16 is provided with a plurality of registers 16a, each of which stores different read data. Therefore, the size of the mosaic unit can be determined regardless of the number of data P that the P/S converter 16 can handle at one time.

Further, the size of the mosaic unit is preset in a plurality of PROMs provided in the address control section 15, and is selected as desired by the output signal of the mosaic control section 19. Therefore, the ratio of the H direction and the V direction of each mosaic unit can be easily changed by changing the data stored in the PROM.

Further, the size of the mosaic unit can be selected by the mosaic control section 19, and this selection control is performed based on the position information of the fader 20. Therefore, by operating the fader 20, it is possible to obtain a mosaic image rich in variation suitable for screen switching, etc.

Furthermore, writing control for the image storage unit 14 is such that writing is performed for each field when the original image is reproduced.
When obtaining a mosaic image, writing is performed once in four fields. Therefore, the representative data does not change even for still images, and a stable mosaic image can be obtained.

As described in detail above, according to the present invention, the image data stored in the image storage unit is read out in synchronization with the scanning timing of the television screen, and the read image data is configured into an image to create a mosaic material. Practical mosaic special effects can be obtained by removing constraints on the size of mosaic units and constraints on creating a video, and in particular, by limiting the writing operation to once every 4 fields when playing back a mosaic image. , it is possible to provide an image processing device that can obtain stable mosaic images without flickering.

[Brief explanation of drawings]

The drawings show an embodiment of the image processing device according to the present invention, and FIG. 1 is a configuration diagram, FIG. 2 is a diagram for explaining the image storage section in FIG. 1, and FIG. 3 is a mosaic image. Figures 4a and 4b are diagrams shown to explain the state in which the representative data is set as the boundary of the mosaic unit, respectively. Figure 5 is the diagram in which the representative data is selected at the center of the mosaic and the image is stored in the image storage unit. FIG. 6 is a diagram showing a schematic configuration of an image storage unit; FIG. 7 is a diagram showing representative data composed of a plurality of pixels; Figure 8a,
b is a diagram shown to explain the address control section, FIG. 9 is a diagram shown to explain the data control section, FIG. 10 is a diagram shown to explain address conversion to obtain a mosaic image, and FIG. Figure 11 shows the configuration of the P/S converter, and Figure 12 shows the configuration of the P/S converter.
13 is a configuration diagram showing the configuration of FIG. 1 with a fader added, and FIGS. 14a and 14b explain the NTSC signal and the writing timing of the image storage section. FIG. 15 is a diagram shown for explaining the movement status of data contents. 11...A/D conversion unit, 12...S/P conversion unit, 13...Writing control unit, 14...Image storage unit, 15...Address control unit, 16...P/S conversion unit, 17... ...D/A converter, 18...data control section, 19...mosaic control section.

Claims (1)

[Claims] 1. In order to match the phase of the image storage unit in which image data is stored and the writing operation of this image storage unit to the color subcarrier information in the stored data, 1 field is divided into 4 fields.
and means for controlling readout of the storage section in synchronization with scanning timing and specifying the readout address for each mosaic according to the size of the mosaic, The image data for each mosaic is held in a register means for parallel-to-serial conversion, and the image data from this register means is replaced with representative data for each mosaic, and the replaced image data is used as new mosaic image data. An image processing device characterized by: