JP6370263B2 - Data transmission apparatus, data transmission / reception system, and data transmission method - Google Patents

Description

  The present invention relates to a data transmission device, a data transmission / reception system, and a data transmission method, and more particularly to a data transmission device, a data transmission / reception system, and a data transmission method that serially transmit digital data obtained by imaging a subject.

  As a technique for serially transmitting digital data obtained by imaging a subject with an imaging device such as an endoscope, for example, a technique disclosed in Patent Document 1 is conventionally known.

  Also, in serial transmission of digital data obtained by imaging a subject with an imaging device such as an endoscope, it occurs due to frequency characteristics of signal lines and / or circuits included in the transmission path of the serial transmission. As a process for suppressing signal waveform deterioration as much as possible, a process of adding a bit value to the digital data, such as 8b / 10b, has been conventionally performed. As a process similar to such a process, for example, in Patent Document 1, 4 bits obtained by dividing 12-bit data of a pixel that is shielded from light or a pixel that causes saturation every three bits from the top is obtained. A process for obtaining 16-bit data of the pixel as data for serial transmission by converting each part of data into 4 bits is disclosed.

  Here, according to the above-described processing disclosed in Patent Document 1, 16-bit data obtained by further adding 4-bit data to 12-bit data obtained by imaging a subject is used as serial transmission data. Therefore, if the transmission speed is not increased according to the number of bits of the serial transmission data, a problem occurs when the image obtained by capturing the subject is displayed on the display device in real time. There is a problem that it will. Therefore, according to the above-described processing disclosed in Patent Document 1, it is necessary to increase the transmission speed in order to ensure transmission quality when serially transmitting digital data obtained by imaging a subject. Problems have arisen in response to the aforementioned problems.

  The present invention provides a data transmission apparatus, a data transmission / reception system, and a data transmission method capable of ensuring transmission quality without increasing the transmission speed when serially transmitting digital data obtained by imaging a subject. The purpose is to do.

  The data transmission device according to one embodiment of the present invention performs A / D conversion on an analog signal obtained by imaging a subject with one or more imaging elements, thereby causing each pixel of the one or more imaging elements to perform A / D conversion. An image capturing unit that generates and outputs digital data representing a gradation value of the image, and when a bit string representing a predetermined gradation value exists in the digital data output from the image capturing unit, the bit sequence is represented by the image capturing unit. A data replacement unit that replaces with a predetermined bit string that is not used for generation of digital data by A / D conversion, and a bit value included in the digital data after replacement by the data replacement unit is either an odd bit or an even bit. Bit value inversion processing is performed in accordance with a predetermined inversion pattern set so as to invert, and the digital data obtained by the bit value inversion processing is parallelized. It has a bit value inversion section for outputting, and a transmission unit that transmits and converts the digital data output in parallel from the bit value inversion section into serial data.

  The data transmission / reception system of one embodiment of the present invention performs A / D conversion on an analog signal obtained by imaging a subject with one or more imaging elements, thereby performing each pixel of the one or more imaging elements. An image capturing unit that generates and outputs digital data representing a gradation value of the image, and when a bit string representing a predetermined gradation value exists in the digital data output from the image capturing unit, the bit sequence is represented by the image capturing unit. A data replacement unit that replaces with a predetermined bit string that is not used for generation of digital data by A / D conversion, and a bit value included in the digital data after replacement by the data replacement unit is either an odd bit or an even bit. Performs bit value inversion processing that inverts in accordance with a predetermined inversion pattern set so as to invert the digital data obtained by the bit value inversion processing. A bit value inversion unit that outputs a larel, a transmission unit that converts digital data output in parallel from the bit value inversion unit into serial data, and transmits serial data transmitted from the transmission unit. A receiver that outputs digital data obtained by converting serial data in parallel, and a bit that reinverts a bit value included in the digital data output from the receiver in accordance with the same pattern as the predetermined inversion pattern A bit value re-inversion unit that performs value re-inversion processing and outputs digital data obtained by the bit value re-inversion processing, and the digital data after the bit value re-inversion processing by the bit value re-inversion unit When the predetermined bit string exists, the predetermined bit string is restored to the bit string before replacement by the data replacement unit. It has a data recovery section which is output, the.

  In the data transmission method of one embodiment of the present invention, the imaging unit performs A / D conversion on an analog signal obtained by imaging a subject with one or more imaging elements, so that the one or more imagings are performed. A step of generating and outputting digital data representing a gradation value for each pixel of the element, and a data replacement unit including a bit string representing a predetermined gradation value in the digital data output from the imaging unit And a step of replacing the bit string with a predetermined bit string that is not used for generating digital data by A / D conversion of the imaging unit, and a bit value inverting unit is a bit included in the digital data after the replacement by the data replacing unit In addition to performing bit value inversion processing that inverts the value according to a predetermined inversion pattern set to invert either odd or even bits, It has a step of parallel output digital data obtained by the processing, transmission unit, and transmitting and converting the digital data output in parallel from the bit value inversion section into serial data.

  According to the data transmission device, data transmission / reception system, and data transmission method of the present invention, transmission quality can be ensured without increasing the transmission speed when serially transmitting digital data obtained by imaging a subject. .

1 is a block diagram illustrating a configuration of a main part of an imaging system according to a first embodiment. FIG. 3 is a diagram illustrating an example of a specific configuration of an imaging unit provided in the imaging apparatus according to the first embodiment. FIG. 6 is a diagram for explaining an example of a scramble process performed in the imaging apparatus according to the first embodiment. FIG. 6 is a diagram for explaining an example of a scramble process performed in the imaging apparatus according to the first embodiment. FIG. 6 is a diagram for explaining an example of a scramble process performed in the imaging apparatus according to the first embodiment. FIG. 6 is a diagram for explaining an example of bit value inversion processing performed in the imaging apparatus according to the first embodiment. FIG. 6 is a diagram for explaining an example of bit value inversion processing performed in the imaging apparatus according to the first embodiment. The figure for demonstrating the modification of the bit value inversion process performed in the imaging device which concerns on a 1st Example. The block diagram which shows the structure of the principal part of the imaging system which concerns on a 2nd Example.

  Embodiments of the present invention will be described below with reference to the drawings.

(First embodiment)
1 to 5 relate to a first embodiment of the present invention.

  For example, as shown in FIG. 1, the imaging system 101 captures an image through an imaging apparatus 1 configured to include a video scope or a rigid endoscope camera head, and a transmission path TL including a metal cable and an insulating circuit. And a camera control unit (hereinafter referred to as CCU) 2 connected to the apparatus 1. FIG. 1 is a block diagram illustrating a configuration of a main part of the imaging system according to the first embodiment.

  The imaging device 1 has a function as a data transmission device. Further, for example, as illustrated in FIG. 1, the imaging device 1 includes an imaging unit 11, a data replacement unit 12, a scramble processing unit 13, a bit value inversion unit 14, and a serial transmission unit 15. It is configured.

  The imaging unit 11 is configured to image light emitted from a subject existing outside the imaging device 1, generate digital data corresponding to the captured light, and output the digital data to the data replacement unit 12. Specifically, for example, as illustrated in FIG. 2, the imaging unit 11 includes an objective optical system 11L, a dichroic prism 11P, imaging elements 11R, 11G, and 11B, A / D conversion circuits 111, 112, 113, and 114. FIG. 2 is a diagram illustrating an example of a specific configuration of the imaging unit provided in the imaging apparatus according to the first embodiment.

  The objective optical system 11L is configured to include one or more lenses to which light emitted from a subject existing outside the imaging apparatus 1 is incident.

  The dichroic prism 11P is configured to separate light emitted through the objective optical system 11L into light of three colors, red light, green light, and blue light.

  The image sensor 11R includes, for example, a CCD or CMOS sensor having the same effective number of pixels as the image sensor 11B. The image sensor 11R is configured to image the red light separated by the dichroic prism 11P, generate an analog signal corresponding to the intensity of the captured red light, and output the analog signal to the A / D conversion circuit 111. Yes. The imaging element 11R is provided with one or more optical black pixels that are pixels that are not used when imaging red light separated by the dichroic prism 11P.

  The image sensor 11G includes, for example, a CCD or CMOS sensor having a larger number of effective pixels than the image sensors 11R and 11B. The image sensor 11G captures the green light separated by the dichroic prism 11P using two different effective pixel groups GP1 and GP2, and outputs an analog signal corresponding to the intensity of the green light captured by the effective pixel group GP1. It is configured to generate and output to the A / D conversion circuit 112, generate an analog electrical signal corresponding to the intensity of the G light imaged by the effective pixel group GP 2, and output it to the A / D conversion circuit 113. Yes. According to the present embodiment, for example, in the effective pixel region formed by two-dimensionally arranging all the effective pixels of the image sensor 11G, the effective pixels belonging to the odd columns are classified into the effective pixel group GP1, It is desirable that the effective pixels belonging to the even columns are classified into the effective pixel group GP2. In addition, the image sensor 11G is provided with one or more optical black pixels, which are pixels that are not used when imaging green light separated by the dichroic prism 11P.

  The image sensor 11B includes, for example, a CCD or CMOS sensor having the same effective number of pixels as the image sensor 11R. The image sensor 11B is configured to image the blue light separated by the dichroic prism 11P, generate an analog signal corresponding to the intensity of the captured blue light, and output the analog signal to the A / D conversion circuit 114. Yes. In addition, the image sensor 11B is provided with one or more optical black pixels that are pixels that are not used when imaging the blue light separated by the dichroic prism 11P.

  The A / D conversion circuit 111 performs A / D conversion on the analog signal output from the image sensor 11R, for example, to express the signal level for each pixel in the analog signal as a 12-bit gradation value. The digital data R is generated and output to the data replacement unit 12 in parallel.

  The A / D conversion circuit 112 performs A / D conversion on the analog signal output from the effective pixel group GP1 of the image sensor 11G, for example, to change the signal level of each pixel in the analog signal to a 12-bit level. The digital data G1 expressed as a tone value is generated and output in parallel to the data replacement unit 12.

  The A / D conversion circuit 113 performs A / D conversion on the analog signal output from the effective pixel group GP2 of the image sensor 11G, for example, to change the signal level of each pixel in the analog signal to a 12-bit level. The digital data G2 represented as a tone value is generated and output in parallel to the data replacement unit 12.

  The A / D conversion circuit 114 performs A / D conversion on the analog signal output from the image sensor 11B, for example, to express the signal level for each pixel in the analog signal as a 12-bit gradation value. The digital data B is generated and output to the data replacement unit 12 in parallel.

  That is, according to the configuration described above, digital data G1 and G2 representing similar gradation values are output from the A / D conversion circuits 112 and 113, respectively. In addition, the imaging unit 11 according to the present embodiment captures light emitted from a subject existing outside the imaging apparatus 1 with a plurality of imaging elements, and performs an analog signal obtained according to the captured light. By performing A / D conversion, digital data of 12 bits × 4 bits representing gradation values for each pixel of the plurality of image sensors is generated, and the generated digital data is output in parallel to the data replacement unit 12 It is configured to be able to.

  Note that the gradation values represented by the digital data R, G1, G2, and B output from the imaging unit 11 are larger than the gradation values of the optical black pixels provided in the imaging elements 11R, 11G, and 11B. It is assumed to be a value. Specifically, the gradation value represented by the digital data R, G1, G2, and B output from the imaging unit 11 is assumed to be a gradation value larger than “100” in hexadecimal notation, for example.

  In addition, the imaging unit 11 according to the present embodiment is not limited to one configured to capture light emitted from a subject existing outside the imaging apparatus 1 with a plurality of imaging elements, and for example, a minute amount of three primary colors. By using one image pickup device provided with a color filter having filters arranged in a Bayer arrangement on the image pickup surface, the light emitted from the subject may be picked up by the one image pickup device.

  When the imaging unit 11 is configured using a CMOS sensor, for example, the A / D conversion circuits 111 to 114 can be built in the imaging elements 11R, 11G, and 11B, and thus the imaging elements 11R, 11G, and 11B. Can directly output the digital data R, G1, G2, and B to the data replacement unit 12.

  In addition, the imaging unit 11 of the present embodiment is not limited to the one having the configuration described above. For example, when the imaging elements 11R, 11G, and 11B have the same effective number of pixels, the imaging element Digital data R obtained by digitizing gradation values of half the number of effective pixels of 11R and digital data B obtained by digitizing gradation values of half the number of effective pixels of the image sensor 11B, respectively. It may be configured to output.

  The data replacement unit 12 replaces the bit string with a predetermined bit string when there is a 12-bit bit string representing a predetermined gradation value in the digital data R and B output in parallel from the imaging unit 11. It is configured to perform processing for parallel output to the scramble processing unit 13. The data replacement unit 12 scrambles the digital data as it is when the digital data R and B output in parallel from the imaging unit 11 do not have a 12-bit bit string representing a predetermined gradation value. The unit 13 is configured to output in parallel.

  The scramble processing unit 13 performs, for example, a scramble process for rearranging each bit value included in the digital data of 12 bits × 4 bits output in parallel from the data replacement unit 12 according to a predetermined scramble pattern, The digital data of 16 bits × 3 bits is generated and output in parallel to the bit value inversion unit 14. The predetermined scramble pattern used for the scramble process of the scramble processing unit 13 is the same as that described above as long as it is set as a pattern that does not change the total number of bits of digital data output in parallel from the data replacement unit 12 at a time. Different patterns may be set.

  The bit value inversion unit 14 uses the bit value included in the digital data output from the scramble processing unit 13 as a unit of processing for 16 bits, that is, digital data for one pixel of each image sensor of the imaging unit 11. As a unit of processing, a bit value inversion process is performed to invert according to a predetermined inversion pattern set so as to invert either an odd bit or an even bit, and obtained by the bit value inversion process. The digital data is output to the serial transmission unit 15 in parallel. The above-described predetermined inversion pattern is set so as to invert either the odd number bit or the even number bit, with digital data for a plurality of predetermined pixels of each image sensor of the imaging unit 11 as one processing unit. It may be.

  For example, the serial transmission unit 15 obtains serial data by performing P / S (parallel / serial) conversion on digital data output in parallel from the bit value inversion unit 14, and uses the obtained serial data to obtain LVDS (Low). It is configured to generate a differential transmission signal according to a voltage differential signaling) method and transmit the generated differential transmission signal to the CCU 2 via the transmission line TL.

  In this embodiment, each of the data replacement unit 12, the scramble processing unit 13, the bit value inversion unit 14, and the serial transmission unit 15 is formed as a separate electronic circuit, for example. Alternatively, they may be formed as part of an integrated circuit such as an FPGA.

  The CCU 2 has a function as a data receiving device. Further, for example, as shown in FIG. 1, the CCU 2 includes a serial reception unit 21, a bit value re-inversion unit 22, a scramble release unit 23, a data restoration unit 24, and a video processing unit 25. It is configured.

  The serial receiver 21 receives the differential transmission signal transmitted from the imaging device 1 via the transmission path TL, acquires serial data corresponding to the received differential transmission signal, and further acquires the acquired serial By performing S / P (serial / parallel) conversion of the data, 16 bits × 3 bits of digital data are generated and output in parallel to the bit value re-inversion unit 22.

  The bit value re-inversion unit 22 performs a bit value re-inversion process that re-inverts the bit value included in the digital data output from the serial reception unit 21 according to the same pattern as the inversion pattern of the bit value inversion unit 14. At the same time, the digital data obtained by the bit value re-inversion processing is output in parallel to the descrambling unit 23.

  The descrambling unit 23 reverses each bit value included in the digital data of 16 bits × 3 bits output from the bit value re-inversion unit 22 from the scramble pattern used in the scramble process of the scramble processing unit 13. By performing the process of rearranging according to the pattern, digital data of 12 bits × 4 bits is generated and output to the data restoring unit 24 in parallel.

  When the digital data output from the descrambling unit 23 includes a predetermined 12-bit bit sequence preset as a bit sequence after replacement by the processing of the data replacement unit 12, the data restoration unit 24 The bit sequence is restored to the bit sequence before replacement by the data replacement unit 12 and processed for parallel output to the video processing unit 25. In addition, the data restoration unit 24, if the digital data output from the scrambler 23 does not include a predetermined 12-bit bit string preset as a bit string after replacement by the data replacement unit 12, The digital data is output in parallel to the video processing unit 25 as it is.

  In the present embodiment, each of the serial receiving unit 21, the bit value re-inversion unit 22, the scramble releasing unit 23, and the data restoring unit 24 is formed as a separate electronic circuit, for example. Alternatively, they may be formed as part of an integrated circuit such as an FPGA.

  The video processing unit 25 includes, for example, a video processing circuit, generates a video signal by performing predetermined signal processing and / or predetermined image processing on the digital data output from the data restoration unit 24, The generated video signal is configured to be output to the display device 3.

  The display device 3 includes, for example, a liquid crystal display and is configured to display an image or the like according to a video signal output from the CCU 2.

  Next, the operation and the like of the imaging system 101 of this embodiment will be described.

  The image pickup unit 11 picks up images of subjects existing in the field of view of the objective optical system 11L with the image pickup devices 11R, 11G, and 11B and outputs the images from the image pickup devices 11R, 11G, and 11B, respectively, when the image pickup apparatus 1 is turned on. The digital data R, G1, G2, and B corresponding to the analog signal to be generated are generated, and the generated digital data are output in parallel to the data replacement unit 12.

  The data replacement unit 12 is, for example, when a bit string corresponding to a gradation value represented by “FF0” in hexadecimal notation exists in the digital data R and B output from the imaging unit 11, that is, 2 When there is a 12-bit bit string represented as “111111110000” in decimal notation, the bit string is replaced with a predetermined bit string such as “0000010101101”, and is output to the scramble processing unit 13 in parallel. In addition, when the bit data corresponding to the gradation value represented by “FF0” in hexadecimal notation does not exist in the digital data R and B output from the imaging unit 11, the data replacement unit 12 The digital data is output in parallel to the scramble processing unit 13 as it is.

  Note that the predetermined bit string described above is not used when generating digital data from an analog signal obtained by imaging a subject, and does not affect the transmission quality when serially transmitting the digital data. As long as it is previously selected from the bit strings belonging to, a bit string other than the bit string represented as “0000010101101” in binary notation may be used.

  Specifically, the above-described predetermined bit string is an optical black provided in each imaging device of the imaging unit 11 as expressed as a gradation value from “000” to “100” in hexadecimal notation, for example. Any bit string that represents a gradation value equal to or lower than the gradation value of the pixel and that is not used to generate the digital data R and B may be used. Further, when selecting the above-described predetermined bit string, it is desirable to select, for example, a bit value of “0” or “1” that is not continuous as much as possible.

  The scramble processing unit 13 converts each bit value included in the 12-bit digital data R, G1, G2, and B output in parallel from the data replacement unit 12 into, for example, as shown in FIGS. 16-bit digital data DIG1, DIG2, and DIG3 are generated by performing scramble processing for rearranging in accordance with a predetermined scramble pattern, and the generated digital data DIG1, DIG2, and DIG3 are output in parallel to the bit value inversion unit 14. To do. 3, 4, and 5 are diagrams for explaining an example of the scramble process performed in the imaging apparatus according to the first embodiment.

  Specifically, as shown in FIG. 3, in the digital data DIG1, each bit value belonging to the upper 8 bits of the digital data G1 and each bit value belonging to the upper 8 bits of the digital data G2 are alternately arranged. It is generated as 16-bit data. Therefore, in the digital data DIG1, the number of consecutive “0” or “1” bit values is 15 regardless of the combination of the bit values included in the digital data G1 and G2 output from the data replacing unit 12. Limited to:

  Further, as shown in FIG. 4, the digital data DIG2 includes 8-bit data obtained by separating the bit values belonging to the lower 8 bits of the digital data B into upper and lower 4 bits and rearranging them alternately, It is generated as 16-bit data obtained by combining 8-bit data obtained by alternately arranging each bit value belonging to the upper 4 bits of data B and each bit value belonging to the lower 4 bits of digital data G1. . Therefore, in the digital data DIG2, the number of consecutive “0” or “1” bit values is 15 times regardless of the combination of the bit values included in the digital data G1 and B output from the data replacing unit 12. Limited to:

  Further, as shown in FIG. 5, the digital data DIG3 includes 8-bit data obtained by separating each bit value belonging to the lower 8 bits of the digital data R into upper and lower 4 bits and rearranging them alternately, It is generated as 16-bit data that is a combination of 8-bit data obtained by alternately arranging each bit value belonging to the upper 4 bits of data R and each bit value belonging to the lower 4 bits of digital data G2. . Therefore, in the digital data DIG3, the number of consecutive “0” or “1” bit values is 15 regardless of the combination of the bit values included in the digital data R and G2 output from the data replacement unit 12. Limited to:

  The bit value reversing unit 14 uses 16 bits as one processing unit, that is, digital data for one pixel of each image sensor of the imaging unit 11 as one processing unit, and outputs either odd bits or even bits. Digital data RIG1 obtained by inverting the bit value included in the digital data DIG1 in accordance with a predetermined inversion pattern RPA set to be inverted, and inversion of the bit value included in the digital data DIG2 in accordance with the predetermined inversion pattern RPA The digital data RIG2 and the digital data RIG3 obtained by inverting the bit value included in the digital data DIG3 in accordance with the predetermined inversion pattern RPA are output in parallel to the serial transmission unit 15.

  Specifically, for example, when the predetermined inversion pattern RPA is set as a pattern for inverting odd bits, the bit value inversion unit 14 performs digital data DIG1, DIG2, and DIG3 as shown in FIG. Digital data RIG1, RIG2, and RIG3 are generated by performing a bit value inversion process. Further, for example, when the predetermined inversion pattern RPA is set as a pattern for inverting even bits, the bit value inversion unit 14 performs bit values as shown in FIG. 7 for the digital data DIG1, DIG2, and DIG3. Digital data RIG1, RIG2, and RIG3 are generated by performing inversion processing. 6 and 7 are diagrams for explaining an example of the bit value inversion processing performed in the imaging apparatus according to the first embodiment.

  Note that the bit value inversion unit 14 of the present embodiment uses a predetermined inversion pattern RPA set as a pattern for inverting each bit value of the digital data output from the scramble processing unit 13 as shown in FIG. It may be used to perform bit value inversion processing. FIG. 8 is a diagram for explaining a modification of the bit value inversion processing performed in the imaging apparatus according to the first embodiment.

  The serial transmission unit 15 generates serial data by performing P / S conversion on the digital data RIG1, RIG2, and RIG3 output from the bit value inversion unit 14, and uses the generated serial data to generate a difference according to the LVDS method. A dynamic transmission signal is generated, and the generated differential transmission signal is transmitted to the CCU 2 via the transmission line TL.

  The serial receiver 21 receives the differential transmission signal transmitted from the imaging device 1 via the transmission path TL, acquires serial data corresponding to the received differential transmission signal, and further acquires the acquired serial By performing S / P conversion on the data, 16-bit digital data RIG1, RIG2, and RIG3 are generated and output in parallel to the bit value re-inversion unit 22.

  The bit value re-inversion unit 22 re-inverts the bit value included in the digital data RIG1 according to a predetermined inversion pattern RPA, and the bit value included in the digital data RIG2 according to the predetermined inversion pattern RPA. Is re-inverted and the digital data DIG3 in which the bit value included in the digital data RIG3 is re-inverted in accordance with the predetermined inversion pattern RPA is output in parallel to the descrambling unit 23.

  The scramble release unit 23 converts each bit value included in the digital data DIG1, DIG2, and DIG3 output from the bit value re-inversion unit 22 into a pattern opposite to the scramble pattern used in the scramble process of the scramble processing unit 13. By performing a rearrangement process in accordance with this, 12-bit digital data R, G1, G2, and B are generated and output in parallel to the data restoration unit 24.

  When the digital data R and B output from the descrambling unit 23 includes a 12-bit bit string represented as “0000010101101” in binary notation, the data restoration unit 24 sets the bit string to “111111110000”. And output to the video processing unit 25 in parallel. In addition, when the 12-bit bit string expressed as “0000010101101” in binary notation does not exist in the digital data R and B output from the descrambling unit 23, the data restoration unit 24 Are output in parallel to the video processing unit 25 as they are.

  The video processing unit 25 generates a video signal by performing predetermined signal processing and / or predetermined image processing on the digital data output from the data restoration unit 24, and displays the generated video signal on the display device 3. Output to. Then, in accordance with the operation of the video processing unit 25 as described above, the image of the subject imaged by the imaging device 1 is displayed on the display device 3.

  As described above, according to the present embodiment, for example, the bit value is not added to the digital data generated by the imaging unit 11 such as 8b / 10b without performing the process of adding the bit value. In the digital data output from the inverting unit 14, the number of consecutive “0” or “1” bit values can be limited to 15 or less. Therefore, according to the present embodiment, it is possible to ensure transmission quality without increasing the transmission speed when serially transmitting digital data obtained by imaging a subject.

  Note that the imaging apparatus 1 according to the present embodiment generates, for example, a differential transmission signal in which register information is superimposed on serial data generated in the serial transmission unit 15, transmits the differential transmission signal to the CCU 2, and register information transmitted to the CCU 2. , The register information returned from the CCU 2 is determined to match, and if the determination result that the two register information does not match is obtained, the differential transmission signal May be retransmitted to CCU2.

(Second embodiment)
FIG. 9 relates to a second embodiment of the present invention.

  The imaging system 102 according to the present embodiment has substantially the same configuration as the imaging system 101 according to the first embodiment except for the scramble release unit 13 and the scramble release unit 23. For this reason, in the present embodiment, detailed description regarding portions having the same configuration and the like as in the first embodiment will be omitted, and description will be mainly given of portions having different configurations and the like from the first embodiment.

  For example, as shown in FIG. 9, the imaging system 102 captures an image through an imaging apparatus 1 </ b> A configured to include a video scope or a rigid endoscope camera head, and a transmission path TL including a metal cable, an insulation circuit, and the like. And a CCU 2A connected to the device 1A. FIG. 9 is a block diagram illustrating a configuration of a main part of the imaging system according to the second embodiment.

  The imaging device 1A has a function as a data transmission device. Further, for example, as illustrated in FIG. 9, the imaging device 1A includes an imaging unit 11, a data replacement unit 12A, a bit value inversion unit 14A, and a serial transmission unit 15A.

  The data replacement unit 12A, when digital data R, G1, G2, and B output in parallel from the imaging unit 11 includes a 12-bit bit string that represents a predetermined gradation value, converts the bit string to a predetermined bit string. And a process for parallel output to the bit value inversion unit 14A. Also, the data replacement unit 12A, when there is no 12-bit bit string representing a predetermined gradation value in the digital data R, G1, G2, and B output in parallel from the imaging unit 11, the digital data Are output in parallel to the bit value inversion unit 14A as they are.

  The bit value inversion unit 14A sets the bit value included in the digital data output from the data replacement unit 12A to 12 bits as one processing unit, that is, digital data for one pixel of each image sensor of the imaging unit 11. Is used as a unit of processing, and a bit value inversion process is performed to invert according to a predetermined inversion pattern set so as to invert either odd bits or even bits, and the bit value inversion process is performed. The data is configured to be output in parallel to the serial transmission unit 15.

  For example, the serial transmission unit 15A acquires serial data by P / S converting digital data output in parallel from the bit value inversion unit 14A, and uses the acquired serial data to perform differential transmission according to the LVDS system. A signal is generated, and the generated differential transmission signal is transmitted to the CCU 2A via the transmission line TL.

  In the present embodiment, the data replacement unit 12A, the bit value inversion unit 14A, and the serial transmission unit 15A may be formed as separate electronic circuits, for example, or Each may be formed as part of an integrated circuit such as an FPGA.

  The CCU 2A has a function as a data receiving device. Further, for example, as illustrated in FIG. 6, the CCU 2A includes a serial reception unit 21A, a bit value re-inversion unit 22A, a data restoration unit 24A, and a video processing unit 25.

  The serial reception unit 21A receives the differential transmission signal transmitted from the imaging apparatus 1A via the transmission path TL, acquires serial data corresponding to the received differential transmission signal, and further acquires the acquired serial data By performing S / P conversion on the data, digital data of 12 bits × 4 bits is generated and output in parallel to the bit value re-inversion unit 22A.

  The bit value re-inversion unit 22A performs a bit value re-inversion process that re-inverts the bit value included in the digital data output from the serial reception unit 21A according to the same pattern as the inversion pattern of the bit value inversion unit 14A. At the same time, the digital data subjected to the bit value re-inversion process is output in parallel to the data restoration unit 24A.

  The data restoration unit 24A, when the digital data output from the bit value re-inversion unit 22A includes a predetermined bit string of 12 bits set in advance as a bit string after replacement by the processing of the data replacement unit 12A, The predetermined bit string is restored to the bit string before the replacement by the data replacing unit 12A, and processing for parallel output to the video processing unit 25 is performed. Further, the data restoration unit 24A, when the digital data output from the bit value re-inversion unit 22A does not include a predetermined 12-bit bit string preset as a bit string after replacement by the data replacement unit 12A. The digital data is output in parallel to the video processing unit 25 as it is.

  In the present embodiment, the serial receiver 21A, the bit value re-inversion unit 22A, and the data restoration unit 24A may be formed as separate electronic circuits, for example. , And may be formed as part of an integrated circuit such as an FPGA.

  Next, the operation and the like of the imaging system 102 of the present embodiment will be described.

  The imaging unit 11 captures images of subjects existing in the visual field range of the objective optical system 11L with the imaging devices 11R, 11G, and 11B, and outputs the images from the imaging devices 11R, 11G, and 11B, respectively, when the imaging apparatus 1A is turned on. The digital data R, G1, G2, and B corresponding to the analog signal to be generated are generated, and the generated digital data are output in parallel to the data replacement unit 12A.

  When the data replacement unit 12A includes, for example, a bit string corresponding to a gradation value represented by “AAA” in hexadecimal notation in the digital data R, G1, G2, and B output from the imaging unit 11. That is, when there is a 12-bit bit string represented as “10101101010” in binary notation, the bit string is replaced with a predetermined first bit string such as “000000000000” and parallel to the bit value inversion unit 14A. Output. Further, the data replacement unit 12A includes a bit string corresponding to a gradation value represented by “555” in hexadecimal notation in the digital data R, G1, G2, and B output from the imaging unit 11, for example. In other words, when there is a 12-bit bit string represented as “0101010101101” in binary notation, the bit string is replaced with a predetermined second bit string such as “0000010010000” to replace the bit value inversion unit 14A Output in parallel. The data replacement unit 12A also includes a bit string corresponding to a gradation value expressed as “AAA” or “555” in hexadecimal notation in the digital data R, G1, G2, and B output from the imaging unit 11. Is not output, the digital data is output in parallel to the bit value inversion unit 14A as it is.

  The predetermined first and second bit strings are not used when digital data is generated from an analog signal obtained by imaging a subject, and the transmission quality when serial transmission of the digital data is performed. As long as it is selected in advance from each bit string belonging to a range that does not affect the bit string, it may be a bit string other than the bit strings represented as “000000000000” and “0000010000000” in binary notation.

  Specifically, each of the imaging elements of the imaging unit 11 is such that the predetermined first and second bit strings are expressed as gradation values from “000” to “100” in hexadecimal notation, for example. May be a bit string that represents a gradation value equal to or lower than the gradation value of the optical black pixel provided in FIG. 1 and that is not used to generate the digital data R, G1, G2, and B. Further, when selecting the above-described predetermined bit string, it is desirable to select, for example, a bit value of “0” or “1” that is not continuous as much as possible.

  The bit value inversion unit 14A uses 12 bits as one processing unit, that is, digital data for one pixel of each image sensor of the imaging unit 11 as one processing unit, and outputs either odd bits or even bits. Digital data SIG1 obtained by inverting the bit value included in the digital data R output from the data replacing unit 12A in accordance with a predetermined inversion pattern RPB set to invert, and data replacement in accordance with the predetermined inversion pattern RPB The digital data SIG2 obtained by inverting the bit value included in the digital data G1 output from the unit 12A and the bit value included in the digital data G2 output from the data replacing unit 12A in accordance with the predetermined inversion pattern RPB In accordance with the digital data SIG3 and the predetermined inversion pattern RPB, the data replacement unit 1 A digital data SIG4 obtained by inverting the bit value included in the digital data B output from the A, and parallel outputs to serial transmission section 15A. The predetermined reversal pattern RPB is set as a pattern substantially similar to the predetermined reversal pattern RPA as illustrated in FIGS.

  The serial transmission unit 15A acquires serial data by performing P / S conversion on the digital data SIG1, SIG2, SIG3, and SIG4 output from the bit value inversion unit 14, and uses the acquired serial data in accordance with the LVDS method. The differential transmission signal is generated, and the generated differential transmission signal is transmitted to the CCU 2A via the transmission line TL.

  The serial reception unit 21A receives the differential transmission signal transmitted from the imaging apparatus 1A via the transmission path TL, acquires serial data corresponding to the received differential transmission signal, and further acquires the acquired serial data By performing S / P conversion on the data, 12-bit digital data SIG1, SIG2, SIG3, and SIG4 are generated and output in parallel to the bit value re-inversion unit 22A.

  The bit value re-inversion unit 22A re-inverts the bit value included in the digital data SIG1 according to a predetermined inversion pattern RPB, and the bit value included in the digital data SIG2 according to the predetermined inversion pattern RPB. Is included in the digital data SIG4 in accordance with the predetermined inversion pattern RPB, digital data G2 in which the bit value included in the digital data SIG3 is reinverted in accordance with the predetermined inversion pattern RPB The digital data B with the bit value re-inverted is output in parallel to the data restoration unit 24A.

  When the data restoration unit 24A includes a 12-bit bit string expressed as “000000000000” in binary notation in the digital data R, G1, G2, and B output from the bit value re-inversion unit 22A, The bit string is restored to “101010101010” and output to the video processing unit 25 in parallel. Further, the data restoration unit 24A has a case where a 12-bit bit string expressed as “0000010010000” in binary notation exists in the digital data R, G1, G2, and B output from the bit value re-inversion unit 22A. Then, the bit string is restored to “010101010101” and output to the video processing unit 25 in parallel. The data restoration unit 24A also includes a 12-bit bit string expressed as “000000000000” or “000001000000” in binary notation in the digital data R, G1, G2, and B output from the bit value re-inversion unit 22A. Is not output, the digital data is output in parallel to the video processing unit 25 as it is.

  The video processing unit 25 generates a video signal by performing predetermined signal processing and / or predetermined image processing on the digital data output from the data restoration unit 24, and displays the generated video signal on the display device 3. Output to. Then, according to the operation of the video processing unit 25 as described above, an image of the subject imaged by the imaging device 1A is displayed on the display device 3.

  As described above, according to the present embodiment, for example, the bit value is not added to the digital data generated by the imaging unit 11 such as 8b / 10b without performing the process of adding the bit value. In the digital data output from the inverting unit 14A, the number of consecutive “0” or “1” bit values can be limited to 11 or less. Therefore, according to the present embodiment, it is possible to ensure transmission quality without increasing the transmission speed when serially transmitting digital data obtained by imaging a subject.

  The present invention is not limited to the above-described embodiments, and various modifications and applications can be made without departing from the spirit of the invention.

1,1A imaging device 2,2A CCU
3 Display device 11 Imaging unit 12, 12A Data replacement unit 13 Scramble processing unit 14, 14A Bit value inversion unit 15, 15A Serial transmission unit 21, 21A Serial reception unit 22, 22A Bit value re-inversion unit 23 Scramble release unit 24, 24A Data restoration unit 25 Video processing units 101 and 102 Imaging system

International Publication Number WO2013 / 031514

Claims (6)

Digital data representing a gradation value for each pixel of the one or more image sensors is generated by performing A / D conversion on an analog signal obtained by imaging an object with one or more image sensors. An imaging unit for output,
When a bit string representing a predetermined gradation value exists in the digital data output from the imaging unit, the bit string is replaced with a predetermined bit string that is not used for generating digital data by A / D conversion of the imaging unit A data replacement unit to perform,
A bit value inversion process for inverting the bit value included in the digital data after replacement by the data replacement unit in accordance with a predetermined inversion pattern set so as to invert either the odd bit or the even bit, A bit value inversion unit for outputting in parallel the digital data obtained by the bit value inversion process;
A transmission unit for converting digital data output in parallel from the bit value inversion unit into serial data and transmitting the data;
A data transmission device comprising: The predetermined bit string is a bit string representing a gradation value equal to or less than a gradation value of an optical black pixel provided in the image sensor, and a bit string not used for generating digital data by A / D conversion of the imaging unit The data transmission device according to claim 1, wherein: A scramble processing unit that outputs the bit values included in the digital data after replacement by the data replacement unit according to a predetermined scramble pattern;
2. The data according to claim 1, wherein the bit value inversion unit performs a process of inverting either odd or even bits on the digital data output from the scramble processing unit and outputs the digital data in parallel. Transmitter device. The data transmission device according to claim 3, wherein the predetermined scramble pattern is set as a pattern that does not change the total number of bits of digital data output in parallel from the data replacement unit at a time. Digital data representing a gradation value for each pixel of the one or more image sensors is generated by performing A / D conversion on an analog signal obtained by imaging an object with one or more image sensors. An imaging unit for output,
When a bit string representing a predetermined gradation value exists in the digital data output from the imaging unit, the bit string is replaced with a predetermined bit string that is not used for generating digital data by A / D conversion of the imaging unit A data replacement unit to perform,
A bit value inversion process for inverting the bit value included in the digital data after replacement by the data replacement unit in accordance with a predetermined inversion pattern set so as to invert either the odd bit or the even bit, A bit value inversion unit for outputting in parallel the digital data obtained by the bit value inversion process;
A transmission unit for converting digital data output in parallel from the bit value inversion unit into serial data and transmitting the data;
Receiving serial data transmitted from the transmitting unit, and receiving in parallel digital data obtained by converting the received serial data;
The bit value included in the digital data output from the receiver is re-inverted according to the same pattern as the predetermined inversion pattern, and is obtained by the bit value re-inversion process. A bit value re-inversion unit for outputting digital data;
When the predetermined bit string is present in the digital data after the bit value re-inversion processing by the bit value re-inversion unit, the predetermined bit string is restored to the bit string before replacement by the data replacement unit and output. A data recovery unit;
A data transmission / reception system comprising: A digital image representing a gradation value for each pixel of the one or more imaging elements by performing A / D conversion on an analog signal obtained by imaging the subject with the one or more imaging elements. Generating and outputting data;
When the data replacement unit includes a bit string representing a predetermined gradation value in the digital data output from the imaging unit, the bit sequence is not used for generating digital data by A / D conversion of the imaging unit. Replacing with a predetermined bit string;
Bit value that the bit value inversion unit inverts the bit value included in the digital data after replacement by the data replacement unit in accordance with a predetermined inversion pattern set to invert either odd bits or even bits Performing inversion processing and outputting in parallel the digital data obtained by the bit value inversion processing;
A transmission unit that converts digital data output in parallel from the bit value inversion unit into serial data and transmits the serial data;
A data transmission method characterized by comprising:

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