Correction device, correction program, and correction method

Abstract

To provide a correction device capable of preventing color blurring in relative to a case where correction for emphasizing a color difference component is performed regardless of an amount of change of a luminance component, a correction program, and a correction method.SOLUTION: A correction device 10 includes: a reception section 110 which receives a modulated video signal; a separation section 120 which separates the video signal into a color difference signal and a luminance signal; and a correction section 150 by which, in a case where an amount of change of a luminance component of a specific frequency band is equal to or more than a specific threshold in a demodulated luminance signal which is demodulated from the luminance signal, correction is performed to emphasize a color difference component corresponding to the luminance component in a demodulated color difference signal, which is demodulated from the color difference signal, in relative to a case where the amount of change is less than the specific threshold.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a correction device, a correction program, and a correction method. [Background technology]

[0002] When video signals are transmitted using an analog modulation method, there may be some bleeding at the boundaries between colors. In particular, the narrower the frequency band for color difference is compared to luminance, such as in the YUV422 format, which shares some information between two adjacent pixels as a set, the greater the color bleeding. In digital video, the boundaries between colors are clear and there is a large change in color. Therefore, when digital video signals are transmitted using analog modulation and analog demodulation methods, there may be noticeable color bleeding.

[0003] Patent Document 1 discloses a video signal processing device. This video signal processing device has a smoothing block that reduces the gradation difference in the plain area of ​​the input digital video signal according to a parameter. This video signal processing device also has a frequency state judgment block that obtains a judgment result of a first case in which the frequency components on the low frequency side lower than a preset frequency are less than the frequency components on the high frequency side when judging the frequency state of the input digital video signal. This frequency state judgment block also obtains a judgment result of a second case in which the frequency components on the low frequency side lower than a preset frequency are more than the frequency components on the high frequency side. This video signal processing device also has a correction parameter output block that outputs a correction parameter that strengthens the smoothing process of the smoothing block more than in the first case when the judgment result is the second case. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2010-199993 A Summary of the Invention [Problem to be solved by the invention]

[0005] There is a method for improving color bleeding by performing a correction to emphasize the color difference components of a predetermined frequency band among the demodulated color difference signals demodulated from the color difference signals. However, there is a problem that unnatural color bleeding becomes noticeable when a correction that emphasizes the color difference components is performed in the same way even in cases where the color bleeding is not originally noticeable and the change in the luminance component is relatively small.

[0006] The present disclosure has been made in consideration of the above-mentioned circumstances, and aims to provide a correction device, a correction program, and a correction method that can improve color bleeding compared to a case where a correction is performed that emphasizes color difference components regardless of the amount of change in luminance component. [Means for solving the problem]

[0007] In order to solve the above problem, the correction device disclosed herein includes a receiving unit that receives a modulated video signal, a separation unit that separates the video signal into a color difference signal and a luminance signal, and a correction unit that, when an amount of change in a luminance component in a predetermined frequency band of a demodulated luminance signal demodulated from the luminance signal is equal to or greater than a predetermined threshold, corrects the demodulated chrominance signal demodulated from the chrominance signal to emphasize the chrominance component corresponding to the luminance component, compared to when the amount of change is less than the predetermined threshold. Effect of the Invention

[0008] According to the present disclosure, it is possible to obtain an effect of improving color bleeding compared to a case where a correction is performed to emphasize a color difference component regardless of the amount of change in a luminance component. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a block diagram showing an example of a hardware configuration of the correction apparatus according to the present embodiment. [Diagram 2] FIG. 2 is a block diagram showing an example of a functional configuration of a correction device according to the present embodiment. [Diagram 3] 11 is a schematic diagram showing an example of a color difference component when the amount of change in the luminance component is equal to or greater than a predetermined threshold value. FIG. [Figure 4] 11 is a schematic diagram showing an example of a color difference component when the amount of change in the luminance component is less than a predetermined threshold value. FIG. [Diagram 5] 6 is a flowchart showing an example of the flow of correction processing in the correction device according to the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an example of an embodiment of the present disclosure will be described with reference to the drawings. In each drawing, the same or equivalent components and parts are given the same reference numerals. In addition, the dimensional ratios of the drawings are exaggerated for the convenience of explanation and may differ from the actual ratios.

[0011] Fig. 1 shows a schematic configuration of a correction device 10 according to this embodiment. As shown in Fig. 1, the correction device 10 according to this embodiment includes a central processing unit (CPU) 11, a read only memory (ROM) 12, a random access memory (RAM) 13, a storage 14, and a communication unit 17. Each component is connected to be able to communicate with each other via a bus 19. The CPU 11 is an example of a computer according to this embodiment.

[0012] The CPU 11 is a central processing unit, and executes various programs and controls each part. That is, the CPU 11 reads a program from the ROM 12 or the storage 14, and executes the program using the RAM 13 as a working area. The CPU 11 controls each of the above components and performs various arithmetic processing according to the program stored in the ROM 12 or the storage 14. In this embodiment, a correction program 12A is stored in the ROM 12. The correction program 12A may be stored in the storage 14.

[0013] The ROM 12 stores various programs and various data. The RAM 13 temporarily stores programs or data as a working area. The storage 14 is configured with a storage device such as an HDD (Hard Disk Drive) or an SSD (Solid State Drive), and stores various programs including an operating system, and various data.

[0014] The communication unit 17 is an interface for communicating with other devices, and uses standards such as Ethernet (registered trademark), FDDI, and Wi-Fi (registered trademark).

[0015] Next, the functional configuration of the correction device 10 according to this embodiment will be described.

[0016] FIG. 2 is a block diagram showing an example of a functional configuration of the correction device 10. As shown in FIG.

[0017] 2, the correction device 10 has, as its functional components, a reception unit 110, a separation unit 120, a demodulation unit 130, an extraction unit 140, a correction unit 150, a conversion unit 160, and an output unit 170. Each functional component is realized by the CPU 11 reading out and executing a correction program 12A stored in the ROM 12.

[0018] The receiving unit 110 receives the modulated video signal. Then, the receiving unit 110 outputs the received video signal to the separating unit 120.

[0019] The separator 120 separates the video signal into a luminance signal and a color difference signal, and outputs the luminance signal and the color difference signal to the demodulator .

[0020] The demodulation unit 130 demodulates the luminance signal into a demodulated luminance signal. Then, the demodulation unit 130 outputs the demodulated luminance signal to the extraction unit 140 and the conversion unit 160. The demodulation unit 130 also demodulates the color difference signal into a demodulated color difference signal. Then, the demodulation unit 130 outputs the demodulated color difference signal to the extraction unit 140 and the correction unit 150. Note that in this embodiment, the luminance signal and the color difference signal are demodulated by a single demodulation unit 130. However, this is not limited to the example. The luminance signal and the color difference signal may be demodulated by separate demodulation units.

[0021] The extraction unit 140 extracts luminance components of a predetermined frequency band from the demodulated luminance signal. For example, the extraction unit 140 inputs the demodulated luminance signal to a band-pass filter to extract the luminance components. In this embodiment, the predetermined frequency band is determined in advance by an administrator of the correction device 10 or the like. However, this is not limiting. For example, the predetermined frequency band may be determined based on the frequency of the demodulated luminance signal.

[0022] The extraction unit 140 also extracts a chrominance component corresponding to the luminance component from the demodulated chrominance signal, and outputs the luminance component and the chrominance component to the correction unit 150.

[0023] When the amount of change in the luminance component is equal to or greater than a predetermined threshold, the correction unit 150 performs correction so as to emphasize the chrominance component compared to when the amount of change is less than the predetermined threshold. Then, the correction unit 150 adds the corrected chrominance component to the demodulated chrominance signal. Then, the correction unit 150 outputs the demodulated chrominance signal to which the corrected chrominance component has been added to the conversion unit 160.

[0024] In this embodiment, the default threshold is determined in advance by an administrator of the correction device 10 or the like. However, this is not limited to this example. For example, the default threshold may be determined based on at least one of the maximum value and the minimum value of the luminance component. For example, a value half the maximum value of the luminance component may be applied as the default threshold.

[0025] In this embodiment, when the amount of change in the luminance component is equal to or greater than a predetermined threshold, the correction unit 150 multiplies the chrominance component by a predetermined positive number. However, this is not limited to the example. When the amount of change in the luminance component is equal to or greater than a predetermined threshold, the correction unit 150 may add a predetermined positive number to the chrominance component, or may divide or subtract a predetermined negative number from the chrominance component. In this case, the predetermined positive number and the predetermined negative number are predetermined by an administrator of the correction device 10 or the like. However, this is not limited to the example. For example, the predetermined positive number and the predetermined negative number may be determined based on at least one of the maximum value and the minimum value of the luminance component.

[0026] Furthermore, when the amount of change in the luminance component is less than a predetermined threshold, the correction unit 150 cancels the correction of the chrominance component. Then, the correction unit 150 outputs a demodulated chrominance signal in which the chrominance component is not corrected to the conversion unit 160. However, this is not a limitation. When the amount of change in the luminance component is less than a predetermined threshold, the correction unit 150 may subtract or subtract a predetermined positive number from or add or multiply the chrominance component by a predetermined negative number.

[0027] FIG. 3 shows an example of the chrominance components when the amount of change in the luminance component is equal to or greater than the predetermined threshold. The upper diagram of FIG. 3 shows the demodulated luminance signal, and the lower diagram of FIG. 3 shows the demodulated luminance signal. As shown in FIG. 3, the frequency band of the demodulated luminance signal is narrower than the frequency band of the demodulated chrominance signal. Then, as shown in FIG. 3, when the amount of change in the luminance component is equal to or greater than the predetermined threshold, the correction unit 150 multiplies the chrominance components by a predetermined positive number. Then, the correction unit 150 adds the chrominance components multiplied by the predetermined positive number to the demodulated chrominance signal.

[0028] Fig. 4 shows an example of the chrominance components when the amount of change in the luminance component is less than the predetermined threshold. The upper diagram of Fig. 4 shows the demodulated luminance signal, and the lower diagram of Fig. 4 shows the demodulated luminance signal. As shown in Fig. 4, when the amount of change in the luminance component is less than the predetermined threshold, the correction unit 150 cancels the correction of the chrominance components.

[0029] The conversion unit 160 converts YUV data, which is a combination of the demodulated chrominance signal in which the chrominance components have been corrected, and the demodulated luminance signal, into RGB data. Note that the conversion unit 160 also converts YUV data, which is a combination of the demodulated chrominance signal in which the correction of the chrominance components has been cancelled, into RGB data. Specifically, the conversion unit 160 obtains the RGB data by inputting the YUV data into a known formula. Then, the conversion unit 160 outputs the RGB data to the output unit 170.

[0030] The output unit 170 outputs the RGB data to a display device provided outside the correction device 10 via the communication unit 17. However, this is not limited to this example. For example, if the correction device 10 includes a display unit, the RGB data may be output to the display unit included in the correction device 10.

[0031] Next, a flow of the correction process in the correction device 10 according to the present embodiment will be described with reference to Fig. 5. The correction process is an example of a process that the correction program 12A causes the CPU 11 as a computer to execute.

[0032] In step S101 of FIG. 5, the CPU 11 receives a modulated video signal.

[0033] In step S103, the CPU 11 separates the video signal into a luminance signal and a color difference signal.

[0034] In step S105, the CPU 11 demodulates the luminance signal and the color difference signal.

[0035] In step S107, the CPU 11 extracts the luminance component from the demodulated luminance signal.

[0036] In step S109, the CPU 11 extracts the color difference components from the demodulated color difference signals.

[0037] In step S111, the CPU 11 determines whether the amount of change in the luminance component is equal to or greater than a predetermined threshold. If the amount of change in the luminance component is equal to or greater than the predetermined threshold (step S111: YES), the CPU 11 proceeds to step S113. On the other hand, if the amount of change in the luminance component is less than the predetermined threshold (step S111: NO), the CPU 11 proceeds to step S117.

[0038] In step S113, the CPU 11 performs correction so as to emphasize the color difference components. Specifically, the CPU 11 multiplies the color difference components by a predetermined positive number.

[0039] In step S115, the CPU 11 adds the corrected color difference components to the demodulated color difference signals.

[0040] In step S117, the CPU 11 cancels the correction of the color difference components.

[0041] In step S119, the CPU 11 converts the YUV data, which is a combination of the demodulated color difference signal and the demodulated luminance signal, into RGB data.

[0042] In step S121, the CPU 11 outputs the RGB data. Specifically, the CPU 11 outputs the RGB data to the display device via the communication unit 17. Then, the correction process ends.

[0043] In this embodiment, the process executed by the CPU after reading the software (program) may be executed by various processors other than the CPU. In this case, examples of the processor include a PLD (Programmable Logic Device) such as an FPGA (Field-Programmable Gate Array) whose circuit configuration can be changed after manufacture, and a dedicated electric circuit such as an ASIC (Application Specific Integrated Circuit) which is a processor having a circuit configuration designed exclusively for executing a specific process. The above-mentioned process may be executed by one of these various processors, or may be executed by a combination of two or more processors of the same or different types (for example, a plurality of FPGAs, a combination of a CPU and an FPGA, etc.). The hardware structure of these various processors is, more specifically, an electric circuit that combines circuit elements such as semiconductor elements.

[0044] In the present embodiment, the program is prestored (installed) in the ROM, but the present invention is not limited to this. The program may be provided in a form recorded on a recording medium such as a CD-ROM (Compact Disc Read Only Memory), a DVD-ROM (Digital Versatile Disc Read Only Memory), or a USB (Universal Serial Bus) memory. The program may be downloaded from an external device via the communication unit 17.

[0045] The process flow described in this embodiment is also one example, and unnecessary steps may be deleted, new steps may be added, or the process order may be changed, without departing from the spirit of the invention.

[0046] Furthermore, the configuration of the correction device 10 described in this embodiment is merely an example, and may be changed according to circumstances without departing from the spirit of the invention. [Explanation of symbols]

[0047] 10 Correction device 11 CPU 12 ROM 12A Correction Program 13 RAM 14. Storage 17 Communications Department 19 Bus 110 Reception 120 Separation section 130 Demodulation section 140 Extraction part 150 Correction section 160 Conversion unit 170 Output section

Claims

1. a reception unit that receives the modulated video signal; a separation unit that separates the video signal into a color difference signal and a luminance signal; a correction unit that, when a change amount of a luminance component in a predetermined frequency band in a demodulated luminance signal demodulated from the luminance signal is equal to or greater than a predetermined threshold, corrects the demodulated chrominance signal demodulated from the chrominance signal so as to emphasize a chrominance component corresponding to the luminance component, compared to when the change amount is less than the predetermined threshold; A correction device comprising:

2. The correction device according to claim 1 , wherein the correction section cancels the correction of the color difference component when the amount of change in the luminance component is less than the predetermined threshold value.

3. 2. The correction device according to claim 1, wherein a frequency band of the demodulated luminance signal is narrower than a frequency band of the demodulated color difference signal.

4. 2. The correction device according to claim 1, further comprising an output section that outputs RGB data converted from YUV data that is a combination of the demodulated color difference signal in which the color difference components have been corrected and the demodulated luminance signal.

5. Accepts modulated video signals, Separating the video signal into a color difference signal and a luminance signal; When an amount of change in a luminance component in a predetermined frequency band of a demodulated luminance signal demodulated from the luminance signal is equal to or greater than a predetermined threshold, a correction is performed so as to emphasize a chrominance component corresponding to the luminance component of a demodulated chrominance signal demodulated from the chrominance signal, compared with a case in which the amount of change is less than the predetermined threshold. Have a computer carry out the process, Correction program.

6. Accepts modulated video signals, Separating the video signal into a color difference signal and a luminance signal; When an amount of change in a luminance component in a predetermined frequency band of a demodulated luminance signal demodulated from the luminance signal is equal to or greater than a predetermined threshold, a correction is performed so as to emphasize a chrominance component corresponding to the luminance component of a demodulated chrominance signal demodulated from the chrominance signal, compared with a case in which the amount of change is less than the predetermined threshold. The processing is carried out by a computer. Correction method.

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