Signal processing device, signal processing method, camera system, video system, and server
To enable HDR video signals of a plurality of signal interfaces to be satisfactorily handled. [Solution] A processing unit processes a linear high dynamic range video signal and obtains a high dynamic range video signal that has undergone a grayscale compression process. The processing unit is able to perform grayscale compression processes of a plurality of signal interfaces. For example, when a grayscale compression process of another signal interface other than a reference signal interface is performed, the processing unit further performs a process of adding characteristics of system gamma of the reference signal interface and a process of cancelling out characteristics of system gamma of the other signal interface.
1. A signal processing system, comprising:
one or more processors configured to
apply a first optical-optical transfer function (OOTF) conversion corresponding to a first signal interface to an input linear video signal, wherein the input linear video signal is a high dynamic range (HDR) signal, and the first signal interface is one of Hybrid Log-Gamma (HLG), Perceptual Quantizer (PQ), and S-Log 3, and
apply a grayscale compression process corresponding to a second signal interface, the second signal interface being one of HLG, PQ, and S-Log 3 but different from the first signal interface.
2. The signal processing system according to claim 1 , wherein the one or more processors are further configured to apply a second OOTF conversion corresponding to the second signal interface to an output of the grayscale compression process corresponding to the second signal interface.
3. The signal processing system according to claim 1 , wherein the one or more processors are further configured to apply an inverse OOTF conversion corresponding to the second signal interface between the first OOTF conversion and the grayscale compression process corresponding to the second signal interface, an output of the grayscale compression process corresponding to the second signal interface being a second signal.
4. The signal processing system according to claim 3 , wherein the one or more processors are configured to apply a grayscale compression process corresponding to the first signal interface to the input linear video signal to obtain a first signal, and apply a grayscale compression process corresponding to a third signal interface directly to an output of the first OOTF conversion process to obtain a third signal, the third signal interface being different from the first and second signal interfaces.
5. The signal processing system according to claim 4 , wherein the one or more processors are further configured to apply the first OOTF conversion corresponding to the first signal interface to the first signal.
6. The signal processing apparatus according to claim 5 , wherein the one or more processors are further configured to apply the first OOTF conversion corresponding to the first signal interface to the first signal in a monitor.
7. The signal processing system according to claim 2 , wherein the one or more processors are further configured to apply the second OOTF conversion corresponding to the first signal interface to an output of the grayscale compression process corresponding to the second signal interface in a monitor.
8. The signal processing system according to claim 4 , wherein the one or more processors are configured to selectively output the first signal, the second signal, or the third signal.
9. The signal processing system according to claim 4 , wherein the one or more processors are further configured to output the first signal, the second signal, and the third signal in parallel.
10. The signal processing system according to claim 1 , wherein the first OOTF conversion is performed by adding a system gamma.
11. The signal processing system according to claim 1 , wherein the one or more processors are configured to apply the first OOTF conversion and the grayscale compression process in a camera controller.
12. The signal processing system according to claim 1 , wherein the first signal interface is a reference signal interface.
13. The signal processing system according to claim 1 , wherein each of the first signal interface and the second signal interface is a signal interface for high dynamic range (HDR) video signals.
14. The signal processing system according to claim 13 , wherein the second signal interface is (HLG) or PQ.
15. The signal processing system according to claim 1 , wherein the one or more processors are configured to apply a grayscale compression process corresponding to a third signal interface which is different from the first and the second signal interfaces.
16. The signal processing system according to claim 1 , further comprising a control panel configured to receive user input.
17. A signal processing method, comprising:
applying, with one or more processors, a first optical-optical transfer function (OOTF) conversion corresponding to a first signal interface to an input linear video signal, wherein the input linear video signal is a high dynamic range (HDR) signal, and the first signal interface is one of Hybrid Log-Gamma (HLG), Perceptual Quantizer (PQ), and S-Log 3; and
applying, with the one or more processors, a grayscale compression process corresponding to a second signal interface the second signal interface, being one of HLG, PQ, and S-Log 3 but different from the first signal interface.
18. A non-transitory computer-readable medium encoded with computer-readable instructions that, when executed by one or more processors, cause the one or more processors to perform a method comprising:
applying a first optical-optical transfer function (OOTF) conversion corresponding to a first signal interface to an input linear video signal, wherein the input linear video signal is a high dynamic range (HDR) signal, and interface is one of Hybrid Log-Gamma (HLG), Perceptual Quantizer (PQ), and S-Log 3; and
applying a grayscale compression process corresponding to a second signal interface, the second signal interface being one of HLG, PQ, and S-Log 3 but different from the first signal interface.