Camera system

Abstract

To realize a camera system in which an IP transmission is used for a communication between an imaging device and a CCU which various signals are appropriately transmitted with a simple configuration.SOLUTION: In a camera system 1, an imaging device 10 side and a camera control unit 50 are connected via a network N by an IP transmission. A signal exchanged between an imaging device main body 20 and a CCU main body 60 can be roughly classified into two types: (1) a signal in which a restriction on a delay time is loose but a degradation at the time of the IP transmission is required to be small; and (2) a signal in which the restriction on the degradation at the time of the IP transmission is loose but the delay time is required to be short. A video signal and a communication audio signal, which are signals to be transmitted, are both input to an encoder for the IP transmission and encoded. Here, as this codec, two types of codec are set: a first codec in which a delay time in processing is relatively long but degradation is small; and a second codec in which degradation is relatively large but delay time in processing is short.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a camera system that uses an imaging device that captures images and a control device that is connected to the imaging device via communication. [Background technology]

[0002] Imaging devices used for capturing images during television broadcasts of digital high-definition broadcasts (4K, 8K, etc.) are actually used as a camera system (system camera) connected to a camera control unit (CCU). In this case, video signals obtained by the imaging device are transmitted from the imaging device to the CCU, and control signals for controlling the imaging device are transmitted from the CCU to the imaging device. In this case, multiple imaging devices installed in different locations may be connected to a single CCU.

[0003] In such a case, for example, the CCU may transmit to a certain imaging device an image (return image) to be displayed in a viewfinder or the like for use in operating the imaging device, similar to the control signal described above. The return image may be, for example, an image obtained by another imaging device with reduced resolution. Furthermore, audio instructions to the cameraman may also be included in this return image signal.

[0004] In Patent Document 1, in order to ensure reliable operation in such a camera system, multiple communication paths are provided between the imaging device and the CCU, and these paths are switched depending on the situation. In this case, the camera system is configured so that the video signal, which is the most important signal in the camera system, is appropriately transmitted to the CCU. There are two types of communication paths in this case: wired communication using an optical composite cable, and wireless communication using a wireless LAN. Of these, IP (Internet Protocol) transmission using IP signals is used for wireless communication. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2022-115285 DISCLOSURE OF THE INVENTION [Problem to be solved by the invention]

[0006] In recent years, IP transmission has become particularly effective due to advances in communication technology. IP transmission offers advantages, such as stable wireless communication regardless of the distance between the imaging device and the CCU, and the ability to transmit large amounts of data, as long as the area is covered by an IP network. It is also possible to perform the above operations stably using only wireless communication.

[0007] On the other hand, in IP transmission, the signal to be transmitted is encoded on the sending side and sent as an IP signal, and the received IP signal is decoded on the receiving side, so circuits to perform this processing are required on the imaging device and CCU sides. There are various encoding methods (codecs) for this, and the method is selected appropriately depending on the signal to be transmitted and its purpose.

[0008] In the camera system described above, the characteristics required of the codec for the video signal transmitted from the imaging device and the return video signal transmitted from the CCU are significantly different. For example, for the video signal, even if some delay occurs during transmission, the highest priority is given to ensuring no signal degradation (high image quality). In contrast, because the return video signal and control signal are used to control the imaging device in real time, the highest priority is given to ensuring no delay for these signals, even if some degradation occurs. For this reason, for example, if the same codec is used for the video signal and the return video signal, problems such as delays or degradation of the return video signal occur. Alternatively, building a camera system by combining different equipment corresponding to each application (or codec) becomes complicated.

[0009] For this reason, it was desirable to realize a camera system with a simple configuration that uses IP transmission for communication between the imaging device and the CCU and transmits various signals appropriately.

[0010] The present invention has been made in view of the above circumstances, and has as its object to solve the above problems. [Means for solving the problem]

[0011] The present invention is a camera system comprising an imaging device that generates a video signal by capturing an image, and a control device that is connected to the imaging device via communication using IP transmission, wherein multiple types of signals including the video signal are exchanged between the imaging device and the control device using the IP transmission, and a first encoding method and a second encoding method that has a shorter processing time during the IP transmission than the first encoding method and causes greater degradation during the IP transmission than the first encoding method are used depending on the signal. In this case, the first encoding method may be used for the video signal, and the second encoding method may be used for signals other than the video signal transmitted from the imaging device side to the control device side. The second encoding method may be used for a return video signal that is transmitted from the control device to the imaging device and output by the imaging device. [Effects of the Invention]

[0012] According to the present invention, a camera system in which various signals are transmitted appropriately can be realized with a simple configuration by using IP transmission for communication between an imaging device and a CCU. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a diagram showing the overall configuration of a camera system according to an embodiment; [Figure 2]FIG. 2 is a diagram showing a configuration of an imaging device in a camera system according to an embodiment. [Figure 3] FIG. 2 is a diagram showing the configuration of a control device side in a camera system according to an embodiment.

[0014] Next, an embodiment of the present invention will be described in detail with reference to the drawings. Fig. 1 shows the overall configuration of a camera system 1 according to an embodiment of the present invention. In this camera system 1, an image capture device 10 and a camera control unit (CCU: control device) 50 are connected via a network N by IP transmission. This allows various signals to be exchanged between the image capture device 10 and the CCU 50.

[0015] Here, the imaging device 10 has an imaging device main body 20 configured similarly to the imaging device in the technology described in Patent Document 1, and a communication unit (imaging device side communication unit) 30 compatible with IP transmission. The imaging device main body 20 transmits video signals obtained by capturing images with an imaging element and audio signals accompanying the video to a CCU (control device) 50. On the other hand, it receives various signals related to the control of the imaging device main body 20 from the CCU 50. To broadcast high-quality images, it is required that these video and audio signals be transmitted without degradation.

[0016] The CCU 50 also has a CCU main body 60 that generates various signals used to control the imaging device main body 20, and a communication unit (CCU side communication unit) 70 that supports IP transmission similar to the communication unit 30. Video signals and audio signals from the imaging device 10 are input to the CCU main body 60, and these signals are further output from the CCU main body 60 to the outside for use in broadcasting, etc.

[0017] The control-related signals transmitted from the CCU 50 (CCU main body 60) to the imaging device 10 (imaging device main body 20) include a tally signal that controls the illumination of a tally light on the imaging device main body 20. Other control-related signals include a return video signal, which is a signal for video (return video) displayed on the imaging device main body 20 for control purposes, and an instruction audio signal, which is a signal for audio instructions from the CCU 50 to the operator (cameraman) of the imaging device main body 20. For example, high image quality (low degradation during transmission) is not generally required for the return video, but since the operator needs to perform operations after viewing the return video quickly, a short delay is required between the time the return video signal is emitted from the CCU main body 60 and the time it is received by the imaging device main body 20. This also applies to the tally signal, instruction audio signal, and the like.

[0018] In contrast, the video and audio signals transmitted from the imaging device main body 20 as described above are required to have little degradation as described above due to the purpose for which they are used, but the restrictions on the delay time from when they are emitted from the imaging device main body 20 to when they are acquired by the CCU main body 60 are looser than those for the signals related to control as described above.

[0019] For this reason, signals exchanged between the imaging device main body 20 and the CCU main body 60 can be roughly divided into two types: (1) signals that require less degradation during IP transmission, but have looser restrictions on delay time, and (2) signals that require less degradation during IP transmission, but have shorter delay time. The video signals and audio signals mentioned above belong to (1), and the control-related signals mentioned above belong to (2). In Figure 1, four types of signals are shown as representatives of such signals: the video signals, communication audio signals, return video signals, and instruction audio signals.

[0020] Note that signals transmitted from the imaging device main body 20 to the CCU main body 60 also include signals related to the control of the imaging device main body 20. Examples of such signals include a response signal indicating that the desired control in the imaging device main body 20 has been completed. Also included in such signals are voice signals (communication voice signals) issued by the operator of the imaging device main body 20 to the operator (administrator) of the CCU main body 60. These signals, by their purpose, belong to the above-mentioned category (2). In other words, the above-mentioned signals (1) and (2) can actually exist in both directions.

[0021] The communication units 30 and 70 in Fig. 1 are configured on the assumption that these two types of signals are available. Fig. 2 shows the configuration of the communication unit (imaging device side communication unit) 30, and Fig. 3 shows the configuration of the communication unit (CCU side communication unit) 70.

[0022] 2, the image capture device main body 20 transmits the video signal and the communication audio signal, and receives the return video signal and the instruction audio signal. The video signal belongs to (1) above, and the communication audio signal, return video signal, and instruction audio signal belong to (2) above. In the following, the audio signal accompanying the video will be treated in the same way as the video signal, or this audio signal will be included in the video signal referred to here.

[0023] The video signal and the audio signal for communication, which are the signals on the transmission side, are both input to an encoder and encoded for IP transmission. Two types of encoding methods (codecs) are set here: a first codec (first encoding method) that has a relatively long processing delay but little degradation, and a second codec (second encoding method) that has a relatively large degradation but short processing delay. In FIG. 2, the video signal (1) is input to an A encoder 31 corresponding to the first codec and encoded, and the audio signal for communication (2) is input to a B encoder 32 corresponding to the second codec and encoded. These encoded signals are input to a multiplexer 33 and multiplexed to become a TS (Transport Stream) signal. This TS signal is converted into an IP signal for IP transmission by a TS / IP converter 34. This IP signal is then transmitted from a transmitter / receiver 35, which modulates it and transmits it as a wireless signal.

[0024] 3, a transmitter / receiver 71 receives this wireless signal and recognizes this IP signal. This IP signal is input to an IP / TS converter 72, which performs the reverse operation of the TS / IP converter 34, and converted into a TS signal. This TS signal is input to a demultiplexer 73, which separates and obtains an encoded video signal and an encoded contact audio signal. The former is input to an A decoder 74 corresponding to a first codec and decoded to obtain a video signal, and the latter is input to a B decoder 75 corresponding to a second codec and decoded to obtain a contact audio signal.

[0025] The video signal and communication audio signal thus reproduced are input to the CCU main body 60, and the video signal is then used as program material for broadcasting, etc. The communication audio signal is output by an intercom or the like used by the operator (administrator) of the CCU main body 60.

[0026] In this configuration, the first codec is applied to the video signal, resulting in a relatively large delay, but with little degradation during transmission, making it possible to obtain high-quality video. On the other hand, the second codec is applied to the communication audio signal, resulting in a relatively large degradation during transmission, but with a short delay, allowing the operator of the CCU main unit 60 to quickly recognize the content.

[0027] 2 and 3 has been described. The signals transmitted from the imaging device main body 20 to the CCU main body 60 (the two signals at the top of the diagram: the video signal and the communication audio signal) are similarly configured in the reverse direction for the signals transmitted from the CCU main body 60 to the imaging device main body 20 (the two signals at the bottom of the diagram: the return video signal and the instruction audio signal). Here, the return video signal and the instruction audio signal both belong to the signal (2) described above, and therefore the second codec is used for them.

[0028] 3, the return video signal and instruction audio signal emitted from the CCU main body 60 are both input to B encoders 76 and 77 corresponding to the second codec, where they are coded, and then input to a multiplexer 78 where they are multiplexed to become a TS signal. This TS signal is converted into an IP signal by a TS / IP conversion unit 79 and transmitted as a wireless signal by the transmission / reception unit 71.

[0029] 2, a transmitter / receiver 35 receives this wireless signal and recognizes this IP signal, which is then input to an IP / TS converter 36 and converted into a TS signal. This TS signal is input to a demultiplexer 37, which separates and obtains an encoded return video signal and an encoded instruction audio signal, which are input to B decoders 38 and 39 and decoded, respectively, to obtain the return video signal and the instruction audio signal.

[0030] The return video signal and instruction audio signal thus reproduced are input to the imaging device main body 20, and the return video signal is output (displayed) on a monitor or viewfinder in the imaging device main body 20 so that the operator of the imaging device main body 20 can view it and refer to it when operating the imaging device main body 20. The instruction audio signal can be output from an intercom or the like in the imaging device main body 20 and used in the same manner.

[0031] According to the above configuration, by using encoders and decoders corresponding to two types of codecs, the first codec is used for video signals that require little degradation during transmission, and the second codec is used for return video signals that require short delay times during processing during transmission. In this case, two types of encoders and decoders corresponding to the two types of codecs can be provided as shown in Figures 2 and 3.

[0032] 2 and 3, the components before and after the encoder on the transmitting side and the components before and after the decoder on the receiving side are the same as those in the conventional configuration when only one type of codec is used. Therefore, the above camera system 1 can be obtained with a simple configuration.

[0033] In the above example, only a video signal and a communication audio signal are exemplified as signals transmitted from the imaging device main body 20, but other signals can also be used as appropriate. For example, when the response signal is used, it can be multiplexed by a multiplexer using a second codec (B decoder) in the same way as the communication audio signal and transmitted in the same way. The operation of the CCU side communication unit can also be performed accordingly. Furthermore, when transmitting a signal corresponding to (1) from the CCU main body side, the same processing can be performed using an A decoder in the CCU side communication unit.

[0034] In the above example, the first codec is applied to the video signal, but in applications where real-time video is particularly required, the second codec may be applied to the video signal. Conversely, if there is a signal other than the video signal exchanged in the camera system that requires suppression of degradation during transmission, the first codec may be applied to this signal.

[0035] In the above example, there are simply two types of codecs, but more types may be provided, taking into consideration the transmission characteristics required for the signals as described above. For example, in Fig. 3, the codec in B encoder 76 for the return video signal and B encoder 77 for the instruction audio signal is the second codec, but as long as the desired transmission characteristics are obtained for these signals, the codecs in these encoders (and the corresponding decoders in the image sensor-side communication unit) do not need to be the same.

[0036] The present invention has been described above based on an embodiment. This embodiment is merely an example, and it will be understood by those skilled in the art that various modifications are possible in the combination of the respective components, and that such modifications are also within the scope of the present invention. [Explanation of symbols]

[0037] 1 camera system 10. Imaging device 20 Imaging device body 30 Communication unit (imaging device side communication unit) 31 A encoder 32, 76, 77 B encoder 33, 78 Multiplexer 34, 79 TS / IP conversion section 35, 71 Transmitter / receiver 36, 72 IP / TS conversion section 37, 73 Demultiplexer 38, 39, 75 B decoder 50 Camera Control Unit (CCU) 60 CCU main unit 70 Communication unit (CCU side communication unit) 74 A decoder N Network

Claims

1. A camera system including an imaging device that captures an image and generates a video signal, and a control device that is connected to the imaging device through communication using IP transmission, a plurality of types of signals including the video signal are exchanged between the imaging device and the control device using the IP transmission; A camera system characterized in that, as encoding methods to be applied during the IP transmission, a first encoding method and a second encoding method which has a shorter processing time during the IP transmission than the first encoding method and causes greater degradation during the IP transmission than the first encoding method are selectively used depending on the signal.

2. The camera system according to claim 1, characterized in that the first encoding method is used for the video signal, and the second encoding method is used for signals other than the video signal transmitted from the imaging device side to the control device side.

3. 3. The camera system according to claim 1, wherein the second encoding method is used for a return video signal transmitted from the control device to the imaging device and output by the imaging device.

Images