JP6235876B2 - Imaging apparatus and image transfer method - Google Patents

Description

  The present invention relates to an imaging apparatus and an image transfer method.

  In recent years, a system has been proposed in which a camera and a terminal device called a smartphone are wirelessly connected via Wi-Fi (registered trademark), and a shooting instruction is issued from the terminal device to the camera via Wi-Fi. In this system, a live view image (through image) acquired by the camera is periodically transmitted to the terminal device, and the user waits for a photo opportunity while viewing the live view image displayed on the screen of the terminal device, and then selects a desired view. A shooting instruction is input to the terminal device at the timing. The input photographing instruction is sent to the camera, and a target image responding to the photographing instruction is photographed and acquired by the camera. Thereafter, the image data of the target image is transmitted from the camera to the terminal device, and the target image is displayed on the terminal device for a certain period of time, so that the user can confirm what kind of image has been taken. That is, the live view image and the target image are displayed on the terminal device in the same manner as the live view image and the target image corresponding to the shooting instruction are displayed on the display screen of the camera alone.

  For images (especially live view images) transmitted to the terminal device, it is only necessary to be able to confirm the general contents of the images, and from the viewpoint of processing time in communication, it is as much as displayed on the camera display screen. Generally, an image having a size (e.g., equivalent to a VGA size) is sent. In addition, the user datagram protocol (UDP), which is a continuous transfer method without re-transmission, is often employed with emphasis on real-time characteristics. Even if a part of one image is lost due to the poor radio wave environment and one image cannot be formed on the terminal device side, the same image is discarded. This is because it is preferable to send the next image from the viewpoint of real-time performance, rather than sending multiple times, rather than accumulating delays due to retransmission.

  However, for a specific target image acquired in response to a shooting instruction, there is a desire to confirm visually what kind of image has been shot (that is, the target image is displayed on the screen of the terminal device due to missing data). It is not preferable that it is not seen above). In view of this, a method has been proposed in which the same image is sent by UDP multiple times during a fixed or user-specified time. As a result, even if an image is lost in the transmission several times during reception on the terminal device side, the image for the total number of times is rarely lost. You can check with. Also, the processing on the terminal device side is easy to implement because it only needs to display an image sent by UDP.

  In addition, when transmitting image data acquired by a camera to an external device wirelessly, a technique for changing the communication speed according to the reception sensitivity of wireless communication has also been proposed (see, for example, Patent Document 1 below).

JP 2007-282097 A

  The terminal device may have a relatively large display screen (that is, a display screen capable of displaying a high-definition image). In such a case, there is a demand for confirming a captured image of the camera with high resolution on the display screen of the terminal device. In a live view image or the like, it is necessary to update the image relatively quickly. Therefore, it is not a good idea to increase the image size (in other words, the resolution) of the transmission image from the viewpoint of communication time. However, since it may take some time for a specific target image corresponding to the shooting instruction, it is conceivable that high-definition image data is sent in response to the above request. However, on the assumption that the same image is sent a plurality of times by UDP, if a high-resolution image (large-size image data) is sent a plurality of times, the transmission time becomes considerably long and the practicality becomes low. When the radio wave environment is good, the reception may be successful in one transmission, but it is inefficient (it takes time) if it is assumed that the transmission is performed a plurality of times.

  SUMMARY An advantage of some aspects of the invention is that it provides an imaging apparatus and an image transfer method capable of efficiently transmitting image data having a desired resolution to an external apparatus.

An imaging apparatus according to the present invention includes an imaging unit that outputs an image signal of a subject, an image processing unit that generates image data based on the output signal of the imaging unit, and a target image for a specific target image in response to a shooting instruction A communication processing unit that transmits data and non-target image data of a first resolution for a non-target image other than the target image data to a wirelessly connected external device, and the image processing unit includes: The target image data having the second resolution higher than the first resolution can be generated, and the communication processing unit completes the transmission regardless of the success or failure of the reception by the external device when transmitting the non-target image data. When the target image data having the second resolution is transmitted using the first protocol, the second protocol for ensuring the successful reception by the external device is used.
An image transfer method corresponding to the function of the imaging apparatus may be formed, or a program for causing a computer to realize the image transfer method may be formed.

  For images where real-time properties are important, such as live view images, the first protocol is used by treating the images as non-target images. On the other hand, for a specific image acquired in response to a shooting instruction, the second protocol is used by treating the image as a target image. Thus, a specific target image in response to the photographing instruction, that is, an image for which relatively detailed visual confirmation is desired is reliably sent to the external device as high-resolution image data (second-resolution target image data). Can meet the above requirements. At this time, efficient transmission is possible as compared with the method based on the premise that the target image data of the second resolution is transmitted a plurality of times by UDP. That is, in the method based on multiple transmissions, the transmission time becomes considerably long regardless of whether the radio wave environment is good or bad. In the imaging apparatus according to the present invention, there is no retransmission when the radio wave environment is good. The transmission is completed in a short time, and even if the radio wave environment is bad, it is only necessary to partially retransmit data that has been poorly received.

  According to the present invention, it is possible to provide an imaging apparatus and an image transfer method capable of efficiently transmitting image data having a desired resolution to an external apparatus.

1 is an overall configuration diagram of an image data transfer system according to an embodiment of the present invention, and a schematic block diagram of a digital camera and a terminal device. It is a figure which shows the structure of a UDP packet. It is a figure which shows the structure of a TCP packet. It is a figure for demonstrating the establishment procedure of the wireless connection between a camera and a terminal device. It is a figure for demonstrating a live view image transfer process. FIG. 7 is a diagram illustrating signal exchange in the vicinity of an input timing of a single shooting instruction according to the first embodiment of the present invention. FIG. 6 is a diagram illustrating signal exchange in the vicinity of an input timing of a continuous shooting instruction according to the first embodiment of the present invention. It is a figure which concerns on 2nd Example of this invention and shows the exchange of the signal in the vicinity of the input timing of a continuous shooting instruction | indication. It is an operation | movement flowchart of the camera which concerns on 2nd Example of this invention. It is a flowchart of the single shooting task according to the second embodiment of the present invention. It is a flowchart of the continuous shooting task which concerns on 2nd Example of this invention. It is a figure which shows the structure of the UDP packet with ACK information which concerns on 3rd Example of this invention.

  Hereinafter, an example of an embodiment of the present invention will be specifically described with reference to the drawings. In each of the drawings to be referred to, the same part is denoted by the same reference numeral, and redundant description regarding the same part is omitted in principle. In this specification, for the sake of simplification, information, signals, physical quantities, and state quantities corresponding to the symbols or signs are described by writing symbols or signs that refer to information, signals, physical quantities, state quantities, or members. Or names of members, etc. may be omitted or abbreviated.

  FIG. 1A is an overall configuration diagram of an image data transfer system according to an embodiment of the present invention. The image data transfer system is composed of electronic devices 1 and 2. The first electronic device 1 is an arbitrary electronic device having a photographing function, and the second electronic device 2 is an arbitrary electronic device having a display screen 2S. However, it is assumed that the electronic devices 1 and 2 can be wirelessly connected to each other. In the following, it is assumed that the electronic device 1 is a digital camera (imaging device) and the electronic device 2 is a portable terminal device (for example, a so-called smartphone).

  FIG. 1B is an internal block diagram of the digital camera 1, and the digital camera 1 includes portions that are referred to by reference numerals 10 to 22.

  The imaging device 11 is a solid-state imaging device such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor) image sensor, and generates an image signal corresponding to an optical image of an object incident through the optical system 10. Output. An image based on the output signal of the image sensor 11 is referred to as a captured image.

  The signal processing unit 12 includes an integrated circuit and the like, and performs a predetermined signal processing (in other words, image processing; AD conversion, noise reduction processing, demosaicing processing, etc.) on the output signal of the image pickup device 11 and takes a captured image. Image data is generated. A CPU (Central Processing Unit) 13 comprehensively controls the operation of each part in the camera 1 while following various instructions and operations input to the operation unit 19. A ROM (Read Only Memory) 14 is composed of a semiconductor memory or the like, and records various programs and various data to be executed by the CPU 13 in a nonvolatile manner. A RAM (Random Access Memory) 15 includes a semiconductor memory or the like, and temporarily records arbitrary data handled by the camera 1. The recording medium 16 is a non-volatile recording medium formed of a semiconductor memory, a magnetic disk, or the like, and records arbitrary data including image data under the control of the CPU 13. A captured image or an arbitrary video is supplied to the display screen 18 via the video encoder 17 and displayed on the display screen 18 under the control of the CPU 13. The display screen 18 is a liquid crystal display panel, for example. The operation unit (operation input unit) 19 includes a touch panel and / or a mechanical operation member attached to the display screen 18 and receives various operations and instructions input from the user. Input contents to the operation unit 19 are transmitted to the CPU 13 through the system controller 20.

  The communication module 21 wirelessly connects to any electronic device including the terminal device 2 in accordance with a predetermined communication standard, and transmits and receives arbitrary data to and from the wirelessly connected electronic device wirelessly using the antenna 22. it can. The communication standard is arbitrary, but in the present embodiment, wireless communication between the camera 1 and the terminal device 2 conforms to the Wi-Fi (registered trademark) standard.

  FIG. 1C shows a partial block diagram of the terminal device 2. The terminal device 2 is referred to by reference numerals 31 to 36 in addition to a display screen 2S composed of a liquid crystal display panel or the like (hereinafter, also referred to as a terminal screen 2S to clarify the distinction from the display screen 18 of the camera 1). Each part. The terminal CPU 31 comprehensively controls the operation of the terminal device 2 while following various instructions and operations input to the terminal operation unit 32. The terminal operation unit (terminal-side operation input unit) 32 includes a touch panel and / or a mechanical operation member attached to the terminal screen 2S, and receives various operations and instruction inputs from the user. The communication module 33 can wirelessly connect to any electronic device including the camera 1 according to a predetermined communication standard, and can transmit and receive arbitrary data wirelessly using the antenna 34 with the wirelessly connected electronic device. . The terminal ROM 35 is composed of a semiconductor memory or the like, and records various programs and various data to be executed by the terminal CPU 31 in a nonvolatile manner. The terminal RAM 36 is composed of a semiconductor memory or the like, and temporarily records arbitrary data handled by the terminal device 2.

  Communication between the camera 1 and the terminal device 2 is possible using UDP (User Datagram Protocol) or TCP (Transmission Control Protocol) which is a kind of communication protocol. In UDP, desired data is transmitted / received by transmitting / receiving a UDP packet. In TCP, desired data is transmitted and received by transmitting and receiving TCP packets. The contents of the UDP and the structure of the UDP packet are defined in RFC 768 in RFC (Request for Comments) describing specifications established by the Internet Engineering Task Force (IETF). The contents of TCP and the structure of the TCP packet are defined by RFC793 in RFC. In the following, it is understood that transmission of a signal (data) by the camera 1 is transmission to the terminal device 2, and transmission of a signal (data) by the terminal device 2 is transmission to the camera 1, even if not specifically stated. It is understood.

  FIG. 2 shows the structure of the UDP packet. A UDP packet consists of a UDP header and a UDP data part. The information stored in the UDP header indicates the source port number (Source Port) indicating the port number of the UDP packet transmission source, and the port number (port number of the device receiving the UDP packet) that should receive the UDP packet. The destination port number (Destination Port), the data length of the entire UDP packet, and a checksum for error detection are included. In the UDP data portion, arbitrary data up to a predetermined maximum data length (65507 bytes in UDP768) is stored.

  FIG. 3 shows the structure of the TCP packet. A TCP packet consists of a TCP header and a TCP data part. The information stored in the TCP header indicates a source port number (Source Port) indicating the port number of the TCP packet source, and a port number (port number of the device receiving the TCP packet) that should receive the TCP packet. A destination port number (Destination Port), a sequence number (Sequence Number), an acknowledgment number (Acknowledgement Number), ACK information, and a checksum for error detection are included. In the TCP data portion, arbitrary data up to a predetermined maximum data length (1460 bytes in UDP793) is stored.

  Considering the case where the camera 1 transmits arbitrary attention image data to the terminal device 2, data transmission processing using UDP by the camera 1 (hereinafter referred to as UDP transmission processing) and TCP using the camera 1 are used. Data transmission processing (hereinafter referred to as TCP transmission processing) will be described. Transmission by UDP transmission processing and TCP transmission processing is also referred to as UDP transmission and TCP transmission, respectively. In both the UDP transmission process and the TCP transmission process, the CPU 13 divides the target image data into a necessary number of data. However, this division is not necessary depending on the data size of the target image data. Consider a case where the first to nth packet data are obtained by division (n is an integer of 2 or more). Each of the first to nth packet data is a part of the target image data.

  In the UDP transmission process, the CPU 13 generates an i-th UDP packet storing the i-th packet data, and sequentially transmits the first to n-th UDP packets to the terminal device 2 using the communication module 21 and the antenna 22. The terminal device 2 can restore the target image data from the received first to n-th UDP packets. i is an integer. In UDP, there is no concept of confirmation response, retransmission, and timeout. Therefore, regardless of whether or not the terminal device 2 has successfully received the first to n-th UDP packets including the first to n-th packet data, the UDP transmission is performed when the first to n-th UDP packets are sequentially transmitted. Processing is complete. However, in the UDP transmission process, the number of transmissions can be set to a plurality of times. In this case, the sequential transmission of the first to nth UDP packets is repeated a plurality of times.

  In the TCP transmission process, the CPU 13 generates an i-th TCP packet storing i-th packet data, and sequentially transmits the first to n-th TCP packets to the terminal device 2 using the communication module 21 and the antenna 22. At this time, the CPU 13 stores the number “i” in the sequence number of the i-th TCP packet, respectively.

  When the terminal device 2 has successfully received the first to i-th TCP packets, the terminal device 2 returns a response TCP packet storing the confirmation response number (i + 1) and the ACK information “1” to the camera 1. To do. The acknowledgment number in the response TCP packet indicates how far the TCP packet has been received, and has a value obtained by adding 1 to the sequence number of the last TCP packet that has been received. The ACK information “1” indicates that the confirmation response number is valid. When the ACK information is “0”, the confirmation response number is invalid. The camera 1 (CPU 13) that has received the response TCP packet has successfully received the first to i-th TCP packets in the terminal device 2 based on the (i + 1) confirmation response number and ACK information in the response TCP packet. Recognize

  If the response TCP packet including the confirmation response number (i + 2) is not received even after a predetermined time has elapsed after the transmission of the (i + 1) th TCP packet, the CPU 13 determines the TCP after the (i + 1) th TCP packet. It is determined that the terminal device 2 has not received the packet, and the (i + 1) th to nth TCP packets are retransmitted (transmitted again) to the terminal device 2. As described above, in the TCP transmission process, the necessary TCP packet is retransmitted until the response TCP packet including the (n + 1) acknowledgment number is received. Therefore, unless a special factor such as a wireless connection interruption occurs, the terminal Successful reception of the first to nth packet data by the device 2 is ensured. The terminal device 2 can restore the target image data from the received first to nth TCP packets.

  The terminal device 2 that has received the first to n-th UDP packets or the first to n-th TCP packets can display the image represented by the attention image data on the terminal screen 2S, and can also display the attention image data in the recording medium in the terminal device 2 (FIG. 1). (C) the terminal RAM 36 or other recording medium (not shown), or can be uploaded to a server device (not shown) via the Internet.

  A procedure for establishing a wireless connection between the camera 1 and the terminal device 2 will be described with reference to FIG. In the following, it is assumed that a specific camera application program (hereinafter referred to as camera application CA) is activated in the terminal device 2. The camera application CA transmits and receives arbitrary signals and data using the communication module 33 and the antenna 34 in cooperation with other programs (for example, communication application programs) as necessary. Various programs that operate on the terminal device 2 (specifically, the terminal CPU 31) including the camera application CA can be stored in the terminal ROM 35 or the terminal RAM 36.

  With the camera application CA, the terminal device 2 first transmits a connection request signal 310 for requesting a wireless connection with the terminal device 2 to the camera 1. The camera 1 that has received the connection request signal 310 transmits a response signal 315 that permits wireless connection with the terminal device 2 to the terminal device 2.

  The connection request signal 310 and the response signal 315 are transmitted and received in the TCP format using HTTP (Hypertext Transfer Protocol). The source port number and the destination port number in the connection request signal 310 are “XX” and “80”, respectively. The port number “XX” is a TCP port number in the terminal device 2 determined by the camera application CA, and has an arbitrary number. The port number “80” is a fixed port number for TCP in the camera 1. Since the camera 1 becomes the transmission side in the response signal 315, the transmission source port number and the destination port number in the response signal 315 are “80” and “XX”, respectively. Further, data “YY” is added to the connection request signal 310. “YY” is a port number for UDP in the terminal device 2 determined by the camera application CA, and has an arbitrary number. When the response signal 315 is received by the terminal device 2, the wireless connection between the camera 1 and the terminal device 2 is completed (in other words, the wireless connection is established).

  The CPU 13 can generate an arbitrary port number “ZZ” at an arbitrary timing after the connection request signal 310 is received, and can transmit the UDP image data signal 320 to the terminal device 2 at an arbitrary timing after the response signal 315 is transmitted. . The port number “ZZ” is a UDP port number in the camera 1. Therefore, the source port number and the destination port number of the UDP packet forming the image data signal 320 are “ZZ” and “YY”, respectively. Image data generated by the camera 1 is added to the UDP packet forming the image data signal 320. After receiving the response signal 315, when the terminal device 2 receives a UDP packet whose destination port number is “YY”, the camera application CA uses the image data from the camera 1 as the image data in the received UDP packet. It is determined that it is data (for example, the above-mentioned attention image data).

  It is also possible to send an arbitrary signal from the terminal device 2 to the camera 1 by UDP. In this case, the source port number and the destination port number of the UDP packet forming the signal from the terminal device 2 are “ YY "and" ZZ "may be used. The same applies to transmission and reception of signals and data by TCP after establishing a wireless connection. In the following, it is assumed that the wireless connection between the camera 1 and the terminal device 2 has been established through the above method.

  By the way, the camera 1 can sequentially perform image processing (hereinafter referred to as live view processing) that generates image data of a captured image from the output signal of the image sensor 11 at a predetermined frame rate. A captured image obtained by the live view processing is called a live view image, and image data of the live view image is called live view image data. The live view processing is realized by the signal processing circuit 12 or by an image processing unit formed by the signal processing circuit 12 and the CPU 13 (the same applies to single shooting processing and continuous shooting processing described later). However, in the following, an expression as if the execution subject of various image processing is the CPU 13 is also used. The CPU 13 can display the sequentially obtained live view images on the display screen 18 as moving images, and can also perform live view image transfer processing. In the live view image transfer process, live view image data obtained sequentially is transferred (ie, transmitted) to the terminal device 2 at a predetermined transfer rate using the communication module 21 and the antenna 22. The live view image may be read as a through image. In the present embodiment, it is assumed that the user controls the operation state of the camera 1 through the operation of the terminal device 2 and confirms the captured image of the camera 1 on the terminal screen 2S.

  The live view image transfer process will be described with reference to FIG. When the wireless connection between the camera 1 and the terminal device 2 is established, the terminal device 2 (camera application CA) performs live view image transfer processing on the camera 1 automatically or according to a predetermined operation input to the terminal operation unit 32. A live view start request signal 350 for requesting the start of is transmitted. The camera 1 that has received the signal 350 returns a response signal 355 that permits the request for the signal 350 to the terminal device 2 and starts live view image transfer processing. Specifically, in the live view image transfer process, the CPU 13 generates live view image data from the output of the image sensor 11 at the same frame rate as a predetermined transfer rate (for example, 30 frames / second), and at the transfer rate described above. The live view image data is transmitted by UDP one after another.

  The resolution of the live view image generated and transmitted in the live view image transfer process is low. The low resolution is a predetermined resolution lower than the high resolution described later, and here, for example, corresponds to (640 × 480) pixels. That is, each live view image has an image size of (640 × 480) pixels. Note that generation, acquisition, transmission, reception, and the like of an image are synonymous with generation, acquisition, transmission, reception, and the like of the image data of the image. Therefore, for example, generation and transmission of a live view image means generation and transmission of live view image data. In the terminal device 2, live view images that are sequentially received are sequentially updated and displayed on the terminal screen 2S by the camera application CA (that is, live view images arranged in time series are displayed on the terminal screen 2S in a moving image format). . By viewing the terminal screen 2S, the user can confirm the state of the subject of the camera 1 and the shooting angle of view.

  Further specific configurations or operations of the image data transfer system based on the above configurations and operations will be described in a plurality of embodiments below. As long as there is no contradiction, any two or more of the embodiments described below can be combined with each other.

<< First Example >>
A first embodiment of the image data transfer system will be described. The user gives a single shooting instruction that instructs the camera 1 to acquire and record one still image or a continuous shooting instruction that instructs the camera 1 to continuously acquire and record m still images. Can be provided to the terminal operation unit 32. m is an integer of 2 or more.

  FIG. 6 shows signal exchange in the vicinity of the input timing of the single shooting instruction. When a single shooting instruction is input to the terminal operation unit 32 after the start of the live view image transfer process, a single shooting command is transmitted from the terminal device 2 by the function of the camera application CA. In response to receiving the single-shot command, the camera 1 captures a single still image (hereinafter referred to as a single-shot image) using the image sensor 11. At this time, in response to the reception of the single shooting command, the camera 1 interrupts the live view image transfer processing, while image processing for generating image data of one single shooting image from the output signal of the image sensor 11. (Hereinafter referred to as single-shot processing). Hereinafter, the single-shot image data is also referred to as single-shot image data.

  In the single shooting process, the CPU 13 can generate high-resolution single-shot image data. The high resolution is a predetermined resolution higher than the above-mentioned low resolution, and corresponds to, for example, about 3 million pixels. Therefore, the image size of a high-resolution image (for example, a single-shot image) is larger than the image size of a low-resolution image (for example, a live view image). The CPU 13 transmits high-resolution single-shot image data to the terminal device 2 and resumes the live view image transfer process when the CPU 13 confirms that the single-shot image data has been received by the terminal device 2. To do. In the terminal device 2, the received high-resolution single-shot image is displayed on the display screen 2S for a certain time by the camera application CA, and then the live view image by the resumed live view image transfer process is sequentially updated and displayed on the display screen 2S. The

  FIG. 7 shows signal exchange in the vicinity of the input timing of the continuous shooting instruction. The continuous shooting instruction includes a continuous shooting start instruction and a continuous shooting end instruction. When a continuous shooting start instruction is input to the terminal operation unit 32 after the start of the live view image transfer process, a continuous shooting start command is transmitted from the terminal device 2 by the function of the camera application CA. When receiving the continuous shooting start command, the camera 1 continuously takes m still images (hereinafter referred to as first to m-th continuous shooting images) using the image sensor 11. At this time, in response to the reception of the continuous shooting start command, the camera 1 interrupts the live view image transfer process, while generating image data of the first to m-th continuous shooting images from the output signal of the image sensor 11. Image processing (hereinafter referred to as continuous shooting processing). Hereinafter, the image data of the i-th continuous shot image is referred to as i-th continuous shot image data. It is assumed that the (i + 1) -th continuous shooting image is acquired after the i-th continuous shooting image.

  When a continuous shooting end instruction is input to the terminal operation unit 32 after the continuous shooting start instruction, a continuous shooting end command is transmitted from the terminal device 2 by the function of the camera application CA. For example, an operation to start pressing a continuous shooting button (not shown) displayed on the display screen 2S corresponds to a continuous shooting start instruction, and an operation to stop pressing the continuous shooting button corresponds to a continuous shooting end instruction. In the continuous shooting process, the CPU 13 continuously acquires continuous shot images from the image sensor 11 at a predetermined frame rate until the continuous shooting end command is received, and the last obtained at the time of receiving the continuous shooting end command. Is the m-th continuous shot image. Alternatively, one continuous shot image taken after receiving the continuous shooting end command may be handled as the m-th continuous shooting image. As described above, the value of m changes depending on the reception timing of the continuous shooting end command (that is, dynamically determined in the continuous shooting instruction).

  The CPU 13 generates low-resolution image data for each sequentially captured image (that is, any one of the first to (m-1) th continuous images) until the continuous shooting end command is received. Then, the obtained low-resolution continuous shot image data is UDP-transmitted to the terminal device 2. That is, the unit process of generating the low-resolution i-th continuous-shot image data and transmitting the UDP to the terminal device 2 is repeatedly executed until the continuous-shooting end command is received. In the terminal device 2, the camera application CA sequentially updates and displays the i-th continuous shot image data (i-th continuous shot image) sequentially received by repeating the unit processing. After receiving the continuous shooting end command, the CPU 13 generates high-resolution m-th continuous shooting image data and transmits it to the terminal device 2 by TCP.

  When the CPU 13 confirms that the high-resolution m-th continuous-shot image data has been received by the terminal device 2, the live view image transfer process is resumed. In the terminal device 2, the received high-resolution m-th continuous-shot image data is displayed on the display screen 2S for a certain time by the camera application CA, and then the live view images obtained by the resumed live view image transfer processing are sequentially displayed on the display screen 2S. Updated display. Note that the value of m may be determined in advance before the continuous shooting start instruction is input. In this case, the continuous shooting end instruction and the continuous shooting end command are unnecessary, and when the number of continuous shots reaches m without waiting for the reception of the continuous shooting end command, the CPU 13 performs high-resolution m-th continuous shooting image data. Generation and TCP transmission may be performed.

  As described above, in this embodiment, UDP is used for an image in which real-time property is important, such as a live view image, while a specific image (single-shot image, m-th continuous shot image) acquired in response to a shooting instruction is used. ) Is used for TCP. Accordingly, a specific image in response to the shooting instruction, that is, a specific image for which relatively detailed visual confirmation is desired can be reliably sent to the terminal device 2 as high-resolution image data. Can be visually confirmed with high-definition images. At this time, efficient transmission is possible as compared with a method based on the premise that high-resolution image data is sent a plurality of times by UDP. That is, in the method based on multiple transmissions, the transmission time becomes considerably long regardless of whether the radio wave environment is good or bad. In the camera 1 of the first embodiment, there is no retransmission when the radio wave environment is good. The transmission is completed in a short time, and even if the radio wave environment is bad, only the packet with poor reception needs to be retransmitted.

<< Second Example >>
A second embodiment of the image data transfer system will be described. The second embodiment and the third embodiment to be described later are embodiments based on the first embodiment, and the matters not specifically described in the second and third embodiments are unless otherwise specified and unless otherwise contradicted. The description of the first embodiment also applies to the second and third embodiments.

  In the first embodiment, the single-shot image and the m-th continuous shot image to which the high-resolution image data is transmitted to the terminal device 2 are referred to as target images for convenience, and the live view in which the low-resolution image data is transmitted. The image and the first to (m−1) th continuous shot images are referred to as non-target images for convenience. In the first embodiment, the high-resolution image data is always transmitted for the target image. However, the high-resolution image data may be transmitted only when a predetermined high-definition transmission request is made. good.

  This will be specifically described. With the camera application CA, the terminal device 2 can transmit a predetermined high-definition transmission request signal for requesting transmission of high-resolution target image data to the camera 1 at an arbitrary timing. When receiving the high-definition transmission request signal, the camera 1 transmits the high-resolution target image data by TCP as in the first embodiment when transmitting the target image data. On the other hand, when the target image data is transmitted when the high-definition transmission request signal is not received, the camera 1 repeats UDP transmission of the low-resolution target image data a predetermined K times. K is an arbitrary integer equal to or greater than 2, but in the following, it is assumed that K = 5.

  When the high-definition transmission request signal is received before the repeated transmission of the low-resolution target image data is performed, the camera (CPU 13) does not transmit the low-resolution target image data once without performing UDP transmission. The target image data is transmitted by TCP. When a high-definition transmission request signal is received during execution of repeated transmission of low-resolution target image data, the camera (CPU 13) transmits the high-resolution target image data by TCP after stopping the repeated transmission.

  FIG. 8 shows signal exchange in the second embodiment near the input timing of the continuous shooting instruction. The operation until the continuous shooting end command is received by the camera 1 is the same as that in the first embodiment (FIG. 7).

  In FIG. 8, it is assumed that the high-definition transmission request signal is not transmitted to the camera 1 before the continuous shooting end command. Therefore, when the continuous shooting end command is received by the camera 1, first, the CPU 13 repeatedly transmits the low resolution m-th continuous shooting image data to the terminal device 2 at a predetermined transfer rate (for example, 5 frames / second). Send UDP. When the high-definition transmission request signal is received by the camera 1 when the number of repeated transmissions of the low-resolution m-th continuous-shot image data is less than K times, the CPU 13 stops the repeated transmission, The m-th continuous shot image data is TCP-transmitted to the terminal device 2. With TCP, data reception success is ensured, so transmission with TCP is sufficient once.

  When the CPU 13 confirms that the high-resolution m-th continuous-shot image data has been received by the terminal device 2, the live view image transfer process is resumed. In the terminal device 2, the received high-resolution m-th continuous-shot image data is displayed on the display screen 2S for a certain time by the camera application CA, and then the live view images obtained by the resumed live view image transfer processing are sequentially displayed on the display screen 2S. Updated display.

  Although not the situation of FIG. 8, when the camera 1 does not receive a high-definition transmission request signal, the low-resolution m-th continuous-shot image data is UDP-transmitted from the camera 1 repeatedly. Therefore, it is expected that the terminal device 2 repeatedly receives the m-th continuous shot image data with low resolution K times. However, since UDP is a communication protocol that does not involve retransmission, it is unclear whether or not all packet data of the m-th continuous-shot image data is normally received by the terminal device 2 each time. However, by repeatedly transmitting the same image data a plurality of times, even if there is a certain degree of data reception failure, there is a high possibility that the entire m-th continuous-shot image data can be obtained correctly from the K received data. That is, when the high-definition transmission request signal is not transmitted, the terminal device 2 acquires the low-resolution m-th continuous-shot image data from the reception result of the low-resolution m-th continuous-shot image data transmitted repeatedly K times by the camera 1. (The acquisition is not always successful), and the low-resolution m-th continuous shot image data is displayed on the display screen 2S for a certain period of time. FIG. 8 shows the case where the target image is the m-th continuous shot image, but the same applies when the target image is a single shot image.

  FIG. 9 shows an operation flowchart of the camera 1. After the wireless connection between the camera 1 and the terminal device 2 is completed and the camera 1 receives the live view start request signal, the live view image transfer process is started in step S1 (that is, the low-resolution live view image). Periodic generation and transmission of data is started). The user can specify the shooting conditions of the camera 1 by inputting a predetermined operation to the terminal operation unit 32. The camera application CA can transmit to the camera 1 a shooting condition setting instruction signal that specifies the shooting conditions of the camera 1 in response to an input operation to the terminal operation unit 32. When the camera 1 has received the shooting condition setting instruction signal in step S2 following step S1, the CPU 13 sets the shooting condition of the camera 1 in step S3 in accordance with the received shooting condition setting instruction signal. From step S2, the process proceeds directly to step S4. The shooting conditions to be set include various shooting conditions such as autofocus conditions and flash emission conditions. Shooting conditions may be set through the operation unit 19 of the camera 1. In steps S4 and S5, the CPU 13 confirms whether a single shooting instruction or a continuous shooting instruction is input. If there is no single shooting instruction or continuous shooting instruction, the process returns to step S2. When a single shooting instruction is input (that is, when a single shooting command is received by the camera 1), a single shooting task is executed. When a continuous shooting instruction is input (that is, when a continuous shooting start command is received by the camera 1), a continuous shooting task is executed. During the execution of the single shooting task or the continuous shooting task, the live view image transfer process is interrupted, and after the single shooting task or the continuous shooting task ends, the process returns to step S1 to restart the live view image transfer process.

  The single shooting task will be described with reference to FIG. FIG. 10 is a flowchart of a single shooting task including the processes of steps S11 to S19. In the single shooting task, first, in step S11, a single shooting image is taken, and an image signal of the single shooting image is acquired from the image sensor 11. In the signal processing circuit 12, the image signal of the single shot image is converted from the RAW signal format to the YUV signal format. In subsequent step S12, single-shot image data in JPEG (Joint Photographic Experts Group) format is generated by the signal processing circuit 12, and a recording task is activated in step S13. The recording task is executed by the CPU 13. In the recording task activated in step S13, single-shot image data in JPEG format is recorded on the recording medium 16 (recording size is arbitrary).

  Then, after substituting 1 for the variable j in step S14, the CPU 13 confirms whether or not a high-definition transmission request signal has already been received from the terminal device 2 in step S15. If a high-definition transmission request signal has already been received, the process proceeds to step 16; otherwise, the process proceeds to step S17.

  In step S <b> 16, the CPU 13 (signal processing circuit 12) generates high-resolution single-shot image data, and transmits the high-resolution single-shot image data to the terminal device 2 using the communication module 21 or the like. The high-resolution single-shot image data to be transmitted is obtained, for example, by performing predetermined resolution conversion and JPEG conversion on the single-shot image expressed in the YUV signal format (transmitting low-resolution single-shot image data). The same applies to cases). Since TCP is used in step S16, TCP packets are retransmitted as necessary until it is confirmed that all the TCP packets for transmitting high-resolution single-shot image data have been received by the terminal device 2. Is called. When the transmission by TCP in step S16 is completed, the single-shot task ends.

  In step S <b> 17, the CPU 13 (signal processing circuit 12) generates low-resolution single-shot image data, and transmits the low-resolution single-shot image data to the terminal device 2 using the communication module 21 or the like. Thereafter, the CPU 13 checks whether or not the variable j is 5 in step S18. If j is not 5, the CPU 13 adds 1 to the variable j in step S19 and then returns to step S15. If j = 5, the single-shot task ends. When no high-definition transmission request signal is received by the camera 1, the UDP transmission in step S17 is repeatedly executed at a predetermined interval (for example, 200 milliseconds). Repeated transmission by UDP can be interrupted by receiving a high-definition transmission request signal (step S15).

  The continuous shooting task will be described with reference to FIG. FIG. 11 is a flowchart of a continuous shooting task including the processes of steps S31 to S37 and S41 to S46. In the continuous shooting task, first, 1 is assigned to the variable i in step S31, and then the i-th continuous shooting image is shot in step S32, and the image signal of the i-th continuous shooting image is acquired from the image sensor 11. The In the signal processing circuit 12, the image signal of the continuous shot image is converted from the RAW signal format to the YUV signal format. In subsequent step S33, the signal processing circuit 12 generates JPEG (Joint Photographic Experts Group) format continuous shot image data, and in step S34, a recording task is activated. The recording task is executed by the CPU 13. In the recording task activated in step S34, the i-th continuous shot image data in JPEG format is recorded on the recording medium 16 (recording size is arbitrary).

  In parallel with the execution of the recording task, in step S35, the CPU 13 (signal processing circuit 12) generates low-resolution i-th continuous-shot image data and uses the communication module 21 or the like to generate the low-resolution i-th continuous-shot image data. The image data is UDP transmitted to the terminal device 2. The low-resolution i-th continuous-shot image data to be transmitted is obtained by, for example, performing predetermined resolution conversion and JPEG conversion on the i-th continuous-shot image data expressed in the YUV signal format (i.e., high-resolution i-th continuous-shot image data). The same applies when sending continuous shot image data). In subsequent step S36, the CPU 13 confirms whether or not a continuous shooting end command is received by the camera 1, and proceeds to step S41 if received, but if not received yet, step S37. After adding 1 to the variable i, the process returns to step S32. The repetition execution period of step S35 is, for example, 200 milliseconds. The value of the variable i when shifting from step S36 to step S41 matches the number of continuous shots (that is, the value of m).

  In step S41, 1 is substituted into the variable j. In subsequent step S42, the CPU 13 confirms whether or not the high-definition transmission request signal is received by the camera 1, and proceeds to step S43 if received, but if not yet received, the step proceeds to step S43. Proceed to S44. In step S43, the CPU 13 (signal processing circuit 12) generates high-resolution m-th continuous-shot image data, and transmits the high-resolution m-th continuous-shot image data to the terminal device 2 using the communication module 21 or the like. . Since TCP is used in step S43, retransmission of TCP packets is performed as necessary until it is confirmed that all TCP packets for transmitting the high-resolution m-th continuous-shot image data have been received by the terminal device 2. Is done. When the transmission by TCP in step S43 is completed, the continuous shooting task ends.

  In step S44, the CPU 13 (signal processing circuit 12) generates low-resolution m-th continuous-shot image data, and transmits the low-resolution m-th continuous-shot image data to the terminal device 2 using the communication module 21 or the like. (However, the data generated in the last step S35 may be used). Thereafter, the CPU 13 checks whether or not the variable j is 5 in step S45. If j is not 5, the CPU 13 adds 1 to the variable j in step S46, and then returns to step S42. If j = 5, the continuous shooting task ends. When no high-definition transmission request signal is received by the camera 1, the UDP transmission in step S44 is repeatedly executed at a predetermined interval (for example, 200 milliseconds). Repeated transmission by UDP can be interrupted by receiving a high-definition transmission request signal (step S42).

  According to the second embodiment, it is possible to perform TCP transmission of high resolution data or multiple times of UDP transmission of low resolution data depending on whether there is a request on the terminal device 2 side. If a high-definition transmission request is made when the terminal screen 2S is relatively large, the same operations and effects as in the first embodiment are achieved. On the other hand, even when the terminal device 2 and the camera application CA support only UDP transmission / reception, the target image can be displayed on the terminal screen 2S without any problem, although the resolution is reduced. When the terminal device 2 and the camera application CA are only compatible with UDP, if the specification that the target image data is always TCP-transmitted is adopted, the target image cannot be displayed on the terminal device 2 side. By using the method of the second embodiment, such a problem is eliminated. That is, it is possible to provide high compatibility with various terminal devices or camera applications.

  In the first embodiment, in the single shooting task of FIG. 10, the processing of step S16 may be always performed after the processing of step S13. In the continuous shooting task of FIG. What is necessary is just to perform the process of step S43.

<< Third Example >>
A third embodiment of the image data transfer system will be described. The camera 1 can be considered as follows. The camera 1 includes an image processing unit that generates image data based on an output signal of the imaging unit, target image data for a specific target image in response to a shooting instruction, and first non-target images other than the target image data. A communication processing unit that transmits non-target image data of one resolution to a wirelessly connected external device. The image processing unit can generate target image data having a second resolution higher than the first resolution, and the communication processing unit can transmit the non-target image data with the external device. When the target image data of the second resolution is transmitted using the first protocol using the first protocol (for example, transmission is completed within the predetermined time T _REF ) regardless of the success or failure of the reception of A second protocol is used to ensure successful reception (for example, ensure successful reception even if the predetermined time T _REF is exceeded).

  As described above, the image processing unit is formed by the signal processing circuit 12 or by the signal processing circuit 12 and the CPU 13. The communication processing unit is realized by the CPU 13, the communication module 21, and the antenna 22, but the CPU 13 controls transmission itself. The terminal device 2 is an example of an external device. The external device may be any electronic device (mobile phone, tablet, personal computer, game device, etc.). The camera 1 may be mounted on any electronic device. In the above description, the first resolution is referred to as low resolution, and the second resolution is referred to as high resolution. The imaging unit of the camera 1 includes at least an imaging element 11 and can also include an optical system 10. An amplifier that amplifies the output signal of the image sensor 11 can also be included in the components of the imaging unit.

  Each of the single shooting instruction and the continuous shooting instruction is a kind of shooting instruction. The continuous shooting instruction may be a so-called bracket shooting instruction. In this case, the first to m-th continuous shot images are shot under different shooting conditions (for example, exposure conditions). In the above description, a shooting instruction is input to the terminal device 2 and a command based on the input shooting instruction is sent to the camera 1 (that is, a shooting instruction is input to the camera 1 via the terminal device 2). ) A shooting instruction may be directly input to the operation unit 19 of the camera 1. Alternatively, a shooting instruction may be input to an arbitrary device other than the camera 1 and the external device (for example, a remote control of the camera 1; not shown), and a command based on the input shooting instruction may be sent from the device to the camera 1. (In other words, a shooting instruction may be input to the camera 1 via the device).

  The single-shot image and the m-th continuous shot image are examples of target images, and the live view image and the first to (m-1) -th continuous shot images are examples of non-target images. However, an image other than the single shot image and the m-th continuous shot image (for example, the first continuous shot image) may be handled as the target image.

  The first and second protocols in the first embodiment are UDP and TCP, respectively. The UDP of the first embodiment does not include a retransmission process of data to be transmitted from the communication processing unit, and the TCP includes the retransmission process.

In the first protocol, importance is attached to the completion of transmission within a predetermined time T _REF . As a result, there may occur a state in which the image display cannot be updated by an external device due to data loss or the like. In the first protocol in the first embodiment or the like, the non-target image data is transmitted only once by UDP. However, if the transmission is completed within a certain time T _REF , the first protocol is free. For example, as long as transmission is completed within a certain time T _REF , the first protocol may be a communication protocol other than UDP, may be a protocol that transmits a plurality of times using UDP without ACK control (retransmission), or ACK control (retransmission). Communication protocol with When a communication protocol with ACK control (retransmission) is adopted as the first protocol, an upper limit is set on the number of retransmissions so that transmission is always completed within time T _REF even if retransmission is performed.

In the second protocol, reliable data transfer is guaranteed even when the time T _REF is exceeded. Although data transfer may be disabled due to power-off of the terminal device 2 or some kind of communication abnormality, such a situation is ignored here. However, considering that such a situation may occur, if transmission is not completed even after time T _LIM has elapsed since the start of transmission in the second protocol (that is, data reception is not completed in the external device), Transmission may be interrupted (that is, new retransmission may not be performed). Time T _LIM is sufficiently longer than time T _REF . The second protocol may be any communication protocol other than TCP as long as it is a communication protocol that ensures successful reception at the external device (terminal device 2) even after the predetermined time T _REF is exceeded. For example, in the second protocol, UD control and retransmission processing may be performed by using ACK information at the application level in the UDP data portion while using UDP.

  As an example of the second protocol, UDP with ACK control capable of executing retransmission processing will be described. Data transmitted using TCP in the first or second embodiment may be transmitted using UDP with ACK control. That is, for example, the transmission in step S16 in FIG. 10 or step S43 in FIG. 11 may be performed by UDP with ACK control.

  FIG. 12 shows the structure of a UDP packet 400 with ACK information, which is a UDP packet used in UDP with ACK control. The UDP packet 400 with ACK information is composed of a UDP header and a UDP data part, as in the UDP packet of FIG. 2, and the UDP header is the same between these packets. However, the UDP data portion 420 of the UDP packet 400 includes a sequence number (Sequence Number), an acknowledgment number (Acknowledgement Number), and ACK information. When the camera 1 is on the transmission side, the UDP data unit 420 further includes image data.

  An operation in which the camera 1 transmits arbitrary attention image data (for example, high-resolution target image data) to the terminal device 2 using UDP with ACK control will be described. Consider a case where the first to nth packet data is obtained by dividing the target image data. In this case, the CPU 13 generates the i-th UDP packet 400 storing the i-th packet data, and sequentially transmits the first to n-th UDP packets 400 to the terminal device 2 using the communication module 21 or the like. At this time, the CPU 13 stores the number “i” in the sequence number of the i-th UDP packet 400, respectively.

  When the terminal device 2 has successfully received the i-th UDP packet 400, the terminal device 2 uses the function of the camera application CA, and the response UDP packet 400 storing the (i + 1) confirmation response number and the ACK information “1”. Is returned to the camera 1. In the response UDP packet 400, the confirmation response number (i + 1) means that the UDP packet 400 including the sequence number “i” has been successfully received, and the acknowledgment number is valid for the ACK information “1”. Point to something. When the ACK information is “0”, the confirmation response number is invalid.

  The camera 1 (CPU 13) that has received the response UDP packet 400 including the confirmation response number (i + 1) and the ACK information “1” recognizes that the terminal device 2 has successfully received the i-th UDP packet 400. If the response UDP packet 400 including the confirmation response number (i + 1) is not received after a predetermined time has elapsed after the i-th UDP packet 400 is transmitted from the camera 1, the CPU 13 determines that the i-th UDP packet 400 is not transmitted to the terminal. The device 2 determines that it has not been received, and retransmits the i-th UDP packet 400 to the terminal device 2 (transmits it again). As described above, in UDP with ACK control, one response UDP packet is returned in response to one UDP packet, and the UDP packet is retransmitted as necessary. As a result, as in the case of TCP, unless a special factor such as a wireless connection interruption occurs, the terminal device 2 can ensure reception success of the first to nth packet data. The terminal device 2 can restore the target image data from the received first to n-th UDP packets 400.

  In addition, the image processing unit can generate target image data having a third resolution lower than the second resolution. For example, when the communication processing unit receives a predetermined request (in the above example, a high-definition transmission request) when transmitting the target image data, the communication processing unit uses the second protocol. Then, the target image data of the second resolution is transmitted, and when the request is not received, the target image data of the third resolution is transmitted using a third protocol different from the second protocol. In the second embodiment, the third resolution is called “low resolution” and is the same as the first resolution. However, the third resolution and the first resolution may be different from each other.

  In the second embodiment, a kind of the third protocol is shown. In the third protocol described in the second embodiment, low-resolution target image data (single-shot image data or m-th continuous-shot image data) is UDP-transmitted a plurality of times, that is, received by an external device (terminal device 2). Regardless of success or failure, low-resolution target image data is repeatedly transmitted from the communication processing unit to the external device. However, the third protocol can be any protocol different from the second protocol. For example, when the second protocol is TCP transmission, the third protocol may be a protocol that transmits low-resolution target image data only once by UDP.

  Further, only the image data of a part of the continuous shot images recorded in the recording medium 16 of the camera 1 may be transferred to the terminal device 2. That is, for example, when the first to ninth continuous shot images are taken at a period of 100 milliseconds, the image data of the first to ninth continuous shot images are all recorded on the recording medium 16, while the first, third, Only the image data of the fifth, seventh and ninth continuous shot images may be transmitted to the terminal device 2. In this case, for example, the first, third, fifth, and seventh continuous images function as non-target images, and the ninth continuous image functions as a target image.

  The first to third resolutions may be predetermined resolutions by the camera 1 or may be specified by signals from the terminal device 2. For example, a resolution designation signal for designating all or part of the first to third resolutions may be added to the live view start request signal 350 (see FIG. 5). All or part of the first to third resolutions may be determined. Alternatively, for example, a resolution designation signal that designates the second resolution may be added to the high-definition transmission request signal, and the camera 1 may determine the second resolution according to the resolution designation signal.

  The camera 1 can be configured by hardware such as an integrated circuit or a combination of hardware and software. Arbitrary specific functions (for example, functions of an image processing unit and a communication processing unit) that are all or a part of the functions realized by the camera 1 are described as a program, and a memory ( It may be stored in the ROM 14 or the RAM 15). Then, the specific function may be realized by executing the program on the program execution device (CPU 13). The program can be stored and fixed on an arbitrary recording medium. The recording medium for storing and fixing the program may be mounted on or connected to a device (server device or the like) different from the camera 1.

  The embodiment of the present invention can be appropriately modified in various ways within the scope of the technical idea shown in the claims. The above embodiment is merely an example of the embodiment of the present invention, and the meaning of the term of the present invention or each constituent element is not limited to that described in the above embodiment. The specific numerical values shown in the above description are merely examples, and as a matter of course, they can be changed to various numerical values.

1 Digital Camera 2 Terminal Device 12 Signal Processing Circuit 13 CPU
21 Communication module

Claims (5)

An imaging unit that outputs an image signal of a subject;
An image processing unit that generates image data based on an output signal of the imaging unit;
A communication processing unit that transmits target image data for a specific target image in response to a shooting instruction and first target non-target image data for a non-target image other than the target image data to a wirelessly connected external device. And comprising
The image processing unit can generate target image data having a second resolution higher than the first resolution,
When transmitting the non-target image data, the communication processing unit transmits the target image data of the second resolution using the first protocol that completes transmission regardless of whether or not the external device has received the data. When using the second protocol to ensure successful reception at the external device ,
Furthermore, the image processing unit can generate target image data having a third resolution lower than the second resolution,
When the communication processing unit receives a predetermined request from the external device when transmitting the target image data, the communication processing unit transmits the second resolution target image data using the second protocol, and If the request is not received, the target image data of the third resolution is transmitted by a third protocol different from the second protocol,
Further, in the third protocol, the target image data of the third resolution is repeatedly transmitted from the communication processing unit to the external device regardless of whether or not the external device has received the image. . The imaging apparatus according to claim 1 , wherein retransmission processing of data to be transmitted from the communication processing unit is not included in the first protocol but is included in the second protocol. Image processing on the output signal of the imaging unit by the image processing unit includes live view processing that sequentially generates image data of a live view image from the output signal of the imaging unit in a predetermined cycle, and the shooting instruction. A single-shot process for generating image data of one still image from the output signal of the imaging unit in response to a single-shoot instruction, and
The imaging apparatus according to claim 1, wherein the non-target image includes the live view image, and the target image includes the one still image. The image processing includes continuous shooting processing for generating image data of a plurality of still images in response to a continuous shooting instruction included in the shooting instruction,
The imaging apparatus according to claim 3, wherein among the plurality of still images, a still image acquired last is included in the target image, and other still images are included in the non-target image. . When the non-target image data is transmitted using the first protocol, the communication processing unit completes the transmission within a predetermined time regardless of the success or failure of the reception by the external device, while the second protocol 5. When the target image data of the second resolution is transmitted using an image, a successful reception at the external device is ensured even if the predetermined time is exceeded. 6. Imaging device.

Images