Calibration device, calibration program, and calibration method

Abstract

The invention relates to a correction device, a correction program, and a correction method. The purpose of the present invention is to provide a correction device, a correction program, and a correction method capable of improving color bleeding compared to a case in which correction for emphasizing a color difference component is performed regardless of the amount of change in a luminance component. A correction device (10) is provided with: a reception unit (110) that receives a modulated video signal; a separation unit 120 that separates the video signal into a color difference signal and a luminance signal; and a correction unit (150) that corrects a luminance component of a predetermined frequency band in a demodulated luminance signal demodulated from the luminance signal when the amount of change in the luminance component of the predetermined frequency band is equal to or greater than a predetermined threshold value than when the amount of change in the luminance component of the predetermined frequency band is less than the predetermined threshold value. The correction is performed so as to emphasize a color difference component corresponding to the luminance component in a demodulated color difference signal demodulated from the color difference signal.

Description

Technical Field

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

[0002] When transmitting video signals in analog modulation, there is a case where the color boundaries may bleed. In particular, in the YUV422 format, where two adjacent pixels are grouped together to share a portion of information, the narrower the color difference band is compared to the brightness, the greater the color bleed. In digital video, the boundaries between colors are clear and the color changes greatly. Therefore, when using analog modulation and analog demodulation to transmit digital video signals, there is a case where the color bleed is obvious.

[0003] Patent document 1 discloses a video signal processing device. The video signal processing device has a smoothing block that reduces the grayscale difference of a plane area of ​​an input digital video signal according to a parameter. In addition, the video signal processing device has a frequency state determination block, which, when determining the frequency state of the input digital video signal, obtains a determination result of a case where the frequency component on the low-frequency side lower than a preset frequency is less than the frequency component on the high-frequency side compared thereto as a first case. In addition, the frequency state determination block also obtains a determination result of a case where the frequency component on the low-frequency side lower than a preset frequency is more than the frequency component on the high-frequency side as a second case. Furthermore, the video signal processing device has a correction parameter output block, which, when the determination result is the second case, outputs a correction parameter that enhances the smoothing process of the smoothing block more than in the first case.

[0004] Prior art literature Patent Literature Patent Document 1: Japanese Patent Application Publication No. 2010-199993 Summary of the invention

[0005] Problem that the invention aims to solve There is a method for improving color bleeding by performing correction to emphasize the color difference component of a predetermined frequency band in a demodulated color difference signal demodulated from a color difference signal. However, if correction to emphasize the color difference component is performed in the same manner even when the color bleeding is not obvious and the amount of change in the brightness component is relatively small, there is a problem that unnatural color bleeding is obvious.

[0006] The present disclosure has been made in view of the above circumstances, and an object thereof is to provide a correction device, a correction program, and a correction method that can improve color bleeding compared to a case where correction of emphasizing a color difference component is performed regardless of the amount of change in a luminance component.

[0007] Solutions for solving problems In order to solve the above-mentioned problem, the correction device disclosed in the present invention includes: a receiving unit, which receives a modulated video signal; a separation unit, which separates the video signal into a color difference signal and a brightness signal; and a correction unit, which performs correction in a manner that emphasizes the color difference component corresponding to the brightness component in the demodulated color difference signal demodulated from the color difference signal when the change amount of the brightness component of a predetermined frequency band in the demodulated brightness signal demodulated from the brightness signal is greater than a predetermined threshold value, compared with a case where the change amount is less than the predetermined threshold value.

[0008] Effects of the Invention According to the present disclosure, there is achieved an effect that color bleeding can be improved compared to a case where correction of emphasizing a color difference component is performed regardless of the amount of change in the luminance component. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 This is a block diagram showing an example of the hardware configuration of the calibration device according to the present embodiment. Figure 2 This is a block diagram showing an example of the functional configuration of the calibration device according to the present embodiment. Figure 3 1 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. Figure 4 1 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. Figure 5 This is a flowchart showing an example of the flow of the calibration process in the calibration device according to the present embodiment. DETAILED DESCRIPTION

[0010] Hereinafter, an example of an embodiment of the present disclosure will be described with reference to the accompanying drawings. In addition, the same reference symbols are given to the same or equivalent components and parts in each drawing. In addition, sometimes, for the convenience of description, the dimensional ratios of the drawings are exaggerated and different from the actual ratios.

[0011] Figure 1 FIG. 2 shows a schematic structure of the calibration device 10 of this embodiment. Figure 1 As shown, the calibration device 10 of this embodiment has each structure of a CPU (Central Processing Unit) 11, a ROM (Read Only Memory) 12, a RAM (Random Access Memory) 13, a memory 14, and a communication unit 17. Each structure is connected to each other so as to be communicable via a bus 19. The CPU 11 is an example of a computer of this embodiment.

[0012] The CPU 11 is a central processing unit that executes various programs or controls various parts. That is, the CPU 11 reads the program from the ROM 12 or the memory 14 and executes the program using the RAM 13 as a work area. The CPU 11 controls the above-mentioned structures and performs various calculations according to the program stored in the ROM 12 or the memory 14. In this embodiment, the ROM 12 stores a correction program 12A. In addition, the correction program 12A may also be stored in the memory 14.

[0013] The ROM 12 stores various programs and various data. The RAM 13 temporarily stores programs and data as a work area. The memory 14 is composed of a storage device such as a 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 calibration device 10 according to the present embodiment will be described.

[0016] Figure 2 1 is a block diagram showing an example of the functional configuration of the calibration device 10 .

[0017] like Figure 2 As shown, the calibration device 10 includes a receiving unit 110, a separating unit 120, a demodulating unit 130, an extracting unit 140, a calibrating unit 150, a converting unit 160, and an outputting unit 170 as functional components. Each functional component is realized when the CPU 11 reads and executes the calibration program 12A stored in the ROM 12.

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

[0019] The separation unit 120 separates the video signal into a luminance signal and a color difference signal, and then outputs the luminance signal and the color difference signal to the demodulation unit 130 .

[0020] The demodulation unit 130 demodulates the brightness signal into a demodulated brightness signal. Then, the demodulation unit 130 outputs the demodulated brightness signal to the extraction unit 140 and the conversion unit 160. In addition, the demodulation unit 130 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. In addition, in the present embodiment, the brightness signal and the color difference signal are demodulated by a single demodulation unit 130. However, this is not limited to this example. The brightness signal and the color difference signal may also be demodulated by their respective demodulation units.

[0021] The extraction unit 140 extracts the brightness component of a predetermined frequency band in the demodulated brightness signal. For example, the extraction unit 140 inputs the demodulated brightness signal to a bandpass filter to extract the brightness component. In the present embodiment, the predetermined frequency band is predetermined by the administrator of the calibration device 10, etc. However, this is not limited to this example. For example, the predetermined frequency band may also be determined based on the frequency of the demodulated brightness signal.

[0022] In addition, the extraction unit 140 extracts the color difference component corresponding to the luminance component in the demodulated color difference signal, and then outputs the luminance component and the color difference component to the correction unit 150 .

[0023] The correction unit 150 performs correction in a manner to emphasize the color difference component when the amount of change in the luminance component is greater than a predetermined threshold value, compared to a case where the amount of change is less than the predetermined threshold value. Then, the correction unit 150 adds the corrected color difference component to the demodulated color difference signal. Then, the correction unit 150 outputs the demodulated color difference signal to which the corrected color difference component is added to the conversion unit 160.

[0024] In the present embodiment, the predetermined threshold is predetermined by the administrator of the calibration device 10. However, the present invention is not limited to this example. For example, the predetermined threshold may be determined based on at least one of the maximum value and the minimum value of the brightness component. For example, a value half of the maximum value of the brightness component may be used as the predetermined threshold.

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

[0026] In addition, the correction unit 150 cancels the correction of the color difference component when the amount of change of the brightness component is less than the predetermined threshold value. Then, the correction unit 150 outputs the demodulated color difference signal of the uncorrected color difference component to the conversion unit 160. However, the present invention is not limited to this example. When the amount of change of the brightness component is less than the predetermined threshold value, the correction unit 150 may subtract or divide the color difference component by a predetermined positive number, or may add or multiply the color difference component by a predetermined negative number.

[0027] Figure 3 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 is shown. Figure 3 The above figure shows the demodulated brightness signal, Figure 3 The following figure shows the demodulated color difference signal. Figure 3 As shown in FIG. 1 , the frequency band of the demodulated luminance signal is narrower than the frequency band of the demodulated color difference signal. Figure 3 As shown, when the amount of change in the luminance component is greater than or equal to a predetermined threshold, the correction unit 150 multiplies the color difference component by a predetermined positive number. Then, the correction unit 150 adds the color difference component multiplied by the predetermined positive number to the demodulated color difference signal.

[0028] Figure 4 An example of a color difference component when the amount of change in the luminance component is less than a predetermined threshold value is shown. Figure 4 The above figure shows the demodulated brightness signal, Figure 4 The following figure shows the demodulated color difference signal. Then, Figure 4 As shown, when the amount of change in the luminance component is less than a predetermined threshold, the correction unit 150 cancels the correction of the color difference component.

[0029] The conversion unit 160 converts the YUV data composed of the demodulated color difference signal and the demodulated brightness signal after the color difference component is corrected into RGB data. In addition, the conversion unit 160 also converts the YUV data composed of the demodulated color difference signal and the demodulated brightness signal after the correction of the color difference component is canceled 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 calibration device 10 via the communication unit 17. However, the present invention is not limited to this example. For example, when the calibration device 10 includes a display unit, the RGB data may be output to the display unit provided in the calibration device 10.

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

[0032] exist Figure 5 In step S101, 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 a luminance component from the demodulated luminance signal.

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

[0037] In step S111, the CPU 11 determines whether the amount of change in the brightness component is greater than a predetermined threshold value. If the amount of change in the brightness component is greater than the predetermined threshold value (step S111: Yes), the CPU 11 proceeds to step S113. On the other hand, if the amount of change in the brightness component is less than the predetermined threshold value (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 component. Specifically, the CPU 11 multiplies the color difference component by a predetermined positive number.

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

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

[0041] In step S119 , the CPU 11 converts YUV data obtained by combining 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 addition, the processing of the CPU reading and executing the software (program) in this embodiment can also be performed by various processors other than the CPU. As the processor in this case, FPGA (Field-Programmable Gate Array) and other PLD (Programmable Logic Device) whose circuit structure can be changed after manufacturing, and ASIC (Application Specific Integrated Circuit) and other processors with circuit structures specially designed to perform specific processing, i.e., dedicated circuits, etc. are exemplified. In addition, the above-mentioned processing can be performed by one of these various processors, or by a combination of two or more processors of the same or different types (for example, a combination of multiple FPGAs and a CPU and FPGA, etc.). In addition, the hardware structure of these various processors is more specifically a circuit that combines circuit elements such as semiconductor elements.

[0044] In addition, in this embodiment, the method of pre-storing (installing) the program in ROM is described, but the present invention is not limited to this. The program can also be provided by recording it in a recording medium such as a CD-ROM (Compact Disc Read Only Memory), a DVD-ROM (Digital Versatile Disc Read Only Memory), and a USB (Universal Serial Bus) memory. In addition, the program can also be downloaded from an external device via the communication unit 17.

[0045] The processing flow described in this embodiment is also an example, and unnecessary steps may be deleted, new steps may be added, or the processing order may be changed within a range that does not deviate from the gist.

[0046] In addition, the configuration of the calibration device 10 described in the present embodiment is an example, and may be changed according to circumstances without departing from the spirit and scope of the invention.

[0047] Description of Reference Numerals 10: Calibration device 11: CPU 12: ROM 12A: Calibration Procedure 13: RAM 14: Memory 17: Ministry of Communications 19: Bus 110: Receiving Department 120: Separation 130: Demodulation Unit 140: Extraction Department 150: Correction Department 160: Transformation Department 170: Output unit.

Claims

1. A calibration device, wherein: include: A receiving unit, receiving a modulated video signal; A separation unit, separating the video signal into a color difference signal and a brightness signal; as well as The correction unit performs correction in a manner that emphasizes the color difference component corresponding to the brightness component in the demodulated color difference signal demodulated from the color difference signal, when the amount of change of the brightness component of a predetermined frequency band in the demodulated brightness signal demodulated from the brightness signal is greater than a predetermined threshold value, compared to a case where the amount of change is less than the predetermined threshold value.

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

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

4. The calibration device according to claim 1, wherein: An output unit is further provided for outputting RGB data converted from YUV data, wherein the YUV data is a combination of the demodulated color difference signal in which the color difference component is corrected and the demodulated luminance signal.

5. A calibration procedure, wherein: Make the computer execute the following processing: receiving a modulated video signal; Separating the video signal into a color difference signal and a brightness signal; and When the amount of change in the brightness component of a predetermined frequency band in the demodulated brightness signal demodulated from the brightness signal is greater than a predetermined threshold, correction is performed in a manner that emphasizes the color difference component corresponding to the brightness component in the demodulated color difference signal demodulated from the color difference signal, compared to a case where the amount of change is less than the predetermined threshold.

6. The calibration procedure according to claim 5, wherein: The computer is further caused to execute the following processing: when the amount of change in the brightness component is less than the predetermined threshold value, the correction of the color difference component is canceled.

7. The calibration procedure according to claim 5, wherein: The frequency band of the demodulated luminance signal is narrower than the frequency band of the demodulated color difference signal.

8. The calibration procedure according to claim 5, wherein: The computer is further caused to execute the following processing: outputting RGB data converted from YUV data, wherein the YUV data is a combination of the demodulated color difference signal in which the color difference component is corrected and the demodulated luminance signal.

9. A calibration method, wherein: The following processing is performed by the computer: receiving a modulated video signal; Separating the video signal into a color difference signal and a brightness signal; and When the amount of change in the brightness component of a predetermined frequency band in the demodulated brightness signal demodulated from the brightness signal is greater than a predetermined threshold, correction is performed in a manner that emphasizes the color difference component corresponding to the brightness component in the demodulated color difference signal demodulated from the color difference signal, compared to a case where the amount of change is less than the predetermined threshold.

10. The calibration method according to claim 9, wherein: The computer further executes the following processing: when the amount of change in the brightness component is less than the predetermined threshold value, the correction of the color difference component is canceled.

11. The calibration method according to claim 9, wherein: The frequency band of the demodulated luminance signal is narrower than the frequency band of the demodulated color difference signal.

12. The calibration method according to claim 9, wherein: The computer also performs the following processing: outputting RGB data converted from YUV data, wherein the YUV data is a combination of the demodulated color difference signal in which the color difference component is corrected and the demodulated luminance signal.

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