Video signal transmitting device, video signal receiving device, and video signal transmitting / receiving system

Abstract

To provide a video signal transmitting device, a video signal receiving device, and a video signal transmitting / receiving system that suppresses image quality degradation when transmitting RAW data in an analog manner.SOLUTION: A video signal transmitting device includes an imaging device in which pixels of multiple colors are arranged in the same line, and which outputs RAW data generated by capturing an image, a conversion unit that rearranges the pixel data of the RAW data output from the imaging device such that pixel data of the same color are consecutive for each of multiple lines in a first direction, a digital-to-analog conversion unit that converts the digital data converted by the conversion unit into an analog signal, and a transmission unit that transmits the analog signal converted by the digital-to-analog conversion unit.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a video signal transmitting device, a video signal receiving device, and a video signal transmitting and receiving system. [Background technology]

[0002] Patent Document 1 describes converting RAW data output from an image sensor into YC (Luminance / Chrominance) data. The YC data can be converted into an analog signal and transmitted in analog form as a composite video signal such as NTSC (National Television System Committee). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2004-088295 A Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, there has been a demand to transmit RAW data output from an image sensor by analog transmission, which is less expensive than digital transmission.

[0005] However, when raw data is converted directly into analog gradation voltages, the spectrum components become broadband, which poses a problem that degradation of image quality is likely to occur in the transmitting circuit, the transmission path, and the receiving circuit during transmission.

[0006] In consideration of the above circumstances, an object of the present disclosure is to provide a video signal transmitting device, a video signal receiving device, and a video signal transmitting / receiving system that suppress image quality degradation when RAW data is transmitted in an analog manner. [Means for solving the problem]

[0007] The video signal transmission device disclosed herein includes an imaging element in which pixels of multiple colors are arranged in the same line, the imaging element outputting RAW data generated by imaging, a conversion unit that rearranges pixel data for the RAW data output from the imaging element so that pixel data of the same color are consecutive for each of multiple lines in a first direction, a digital-to-analog conversion unit that converts the digital data converted by the conversion unit into an analog signal, and a transmission unit that transmits the analog signal converted by the digital-to-analog conversion unit.

[0008] The video signal receiving device of the present disclosure includes a receiving unit that receives an analog signal transmitted from the video signal transmitting device of the present disclosure, an analog-to-digital conversion unit that converts the analog signal received by the receiving unit into digital data, and an inverse conversion unit that inversely converts the color sequence of the RAW data output by the imaging element for each line in the first direction for the digital data output from the analog-to-digital conversion unit.

[0009] A video signal transmission / reception system according to the present disclosure includes the video signal transmission device according to the present disclosure and the video signal reception device according to the present disclosure. Effect of the Invention

[0010] According to the video signal transmission device of the present disclosure, when RAW data is transmitted in an analog manner, it is possible to transmit the RAW data while suppressing degradation in image quality.

[0011] According to the video signal receiving device of the present disclosure, when RAW data is transmitted in an analog manner, it is possible to receive an analog signal with reduced degradation in image quality.

[0012] According to the video signal transmission and reception system of the present disclosure, when RAW data is transmitted in an analog manner, it is possible to transmit and receive the data while suppressing deterioration in image quality. [Brief description of the drawings]

[0013] [Figure 1] 1 is a diagram showing a schematic configuration of a video signal transmission / reception system according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is a diagram showing a schematic configuration of an imaging element. [Diagram 3] 10A and 10B are diagrams for explaining processing performed when an analog signal is transmitted in a video signal transmitting device. [Figure 4] FIG. 2 is a diagram showing a schematic configuration of an imaging element. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Next, an embodiment of the present disclosure will be described with reference to the drawings. Fig. 1 is a diagram showing a schematic configuration of a video signal transmitting and receiving system 1 according to an embodiment of the present disclosure. Fig. 2 is a diagram showing a schematic configuration of an imaging element.

[0015] As shown in FIG. 1, a video signal transmission / reception system 1 of the present embodiment includes a video signal transmission device 10 and a video signal reception device 20.

[0016] The video signal transmission device 10 includes an image sensor 11, a conversion unit 12, a synchronization signal generation unit 13, a synthesis unit 14, a DAC (Digital to Analog Converter) 15, and a transmission unit 16. The DAC 15 is an example of a digital-to-analog conversion unit in the technology of the present disclosure.

[0017] The image sensor 11 is an image sensor in which pixels of multiple colors are arranged in the same horizontal line, and outputs RAW data generated by capturing an image. Note that the horizontal direction is an example of a first direction in the technology of the present disclosure.

[0018] As shown in Fig. 2, the image sensor 11 of this embodiment has three color pixels, red, green, and blue, arranged in a Bayer array. Note that, hereinafter, red pixels may be referred to as pixels R, green pixels as pixels G, and blue pixels as pixels B.

[0019] This Bayer array has two lines per period in the vertical direction and two lines per period in the horizontal direction. The first horizontal line is a Bayer array of four pixels: pixel R and pixel G, and the second horizontal line is a Bayer array of four pixels: pixel G and pixel B.

[0020] Returning to FIG. 1, the conversion unit 12 performs a process of rearranging pixel data for the RAW data output from the imaging element 11 so that pixel data of the same color are consecutive for each set of multiple horizontal lines.

[0021] The sync signal generating unit 13 generates a sync signal for analog transmission.

[0022] The synthesizer 14 synthesizes the digital data output from the converter 12 and the sync signal generated by the sync signal generator 13 to generate digital data.

[0023] The DAC 15 converts the digital data converted by the conversion unit 12 into an analog signal, and more specifically, converts the digital data obtained by synthesizing the digital data output from the conversion unit 12 and the synchronization signal generated by the synchronization signal generation unit 13 by the synthesis unit 14 into an analog signal.

[0024] The transmitting unit 16 transmits the analog signal converted by the DAC 15 .

[0025] The video signal receiving device 20 includes a receiving unit 21, an ADC (Analog to Digital Converter) 22, and an inverse conversion unit 23. The ADC 22 is an example of an analog-to-digital conversion unit in the technology of the present disclosure.

[0026] The receiving unit 21 receives an analog signal transmitted from the video signal transmitting device 10. The ADC 22 converts the analog signal received by the receiving unit 21 into digital data. The inverse conversion unit 23 inversely converts the digital data output from the ADC 22 into the color sequence of the RAW data output by the imaging element 11 for each horizontal line.

[0027] Next, a process performed when transmitting an analog signal in the video signal transmitting device 10 of the video signal transmitting and receiving system 1 of this embodiment will be described with reference to FIG.

[0028] The video signal transmitting device 10 of this embodiment directly converts RAW data into an analog signal and transmits it.

[0029] The bandwidth of a typical component signal (analog signal) that includes a luminance signal and a color difference signal is determined by the resolution of the input video.

[0030] On the other hand, when converting RAW data directly into an analog signal, the pixel values ​​must be converted directly into an analog signal, which results in a wider image signal band and larger amplitude, which requires a very high-performance DAC in the circuit design, making it impractical.

[0031] In order to solve such a problem, the video signal transmitting device 10 of the present embodiment performs the following process when directly converting RAW data into an analog signal.

[0032] 3, the conversion unit 12 includes a line even / odd determination circuit 31, a line memory 32 for even lines, a line memory 33 for odd lines, a data read circuit 34, and a data read control circuit 35. The line memory 32 for even lines and the line memory 33 for odd lines are examples of a storage unit in the technology of the present disclosure.

[0033] The conversion unit 12 rearranges the pixel data so that pixel data of the same color are consecutive for every two horizontal lines, which is the period of the Bayer array in the vertical direction.

[0034] Specifically, the RAW data output from the image sensor 11 is judged for each horizontal line by a line even / odd judgment circuit 31 as to whether it is an even line or an odd line, and if it is an even line, it is stored in a line memory 32 for even lines, and if it is an odd line, it is stored in a line memory 33 for odd lines.

[0035] The data read control circuit 35 controls the data read circuit 34 to continuously and sequentially read pixel data of the same color from the line memory 32 for even lines and the line memory 33 for odd lines, and output the data as digital data to the subsequent stage for each line.

[0036] Specifically, the data read control circuit 35 rearranges the pixel data of pixels R and B in the Bayer array so that pixel data of the same color are consecutive, and outputs the pixel data as digital data for the Nth line, and rearranges the pixel data of pixel G in the Bayer array in the horizontal arrangement order, and outputs the pixel data as digital data for the N+1th line.

[0037] 3, in the image sensor 11, pixels R1, G2, R2, and G4 are arranged in order from the left as pixels on the Nth line, and pixels G1, B1, G3, and B2 are arranged in order from the left as pixels on the N+1th line. Although not shown in the figure, in addition to the above pixels, pixels having the same arrangement pattern are periodically arranged in both the horizontal and vertical directions in the image sensor 11.

[0038] The Nth line of RAW data output from the imaging element 11 is stored in a line memory 32 for even lines by a line even-odd determination circuit 31, and the N+1th line of RAW data output from the imaging element 11 is stored in a line memory 33 for odd lines by the line even-odd determination circuit 31.

[0039] The data read control circuit 35 controls the data read circuit 34 to rearrange the pixel data from the beginning in the order of pixel R1, pixel R2, pixel B1, and pixel B2, and output the rearranged data as digital data for the Nth line.

[0040] The data read control circuit 35 also controls the data read circuit 34 to rearrange the pixel data from the beginning in the order of pixel G1, pixel G2, pixel G3, and pixel G4, and output the rearranged data as digital data for the (N+1)th line.

[0041] The synthesizer 14 generates digital data by synthesizing the digital data output from the converter 12 and the synchronization signal generated by the synchronization signal generator 13. The DAC 15 converts the digital data generated by the synthesizer 14 into an analog signal.

[0042] Subjects such as people or landscapes captured by the image sensor 11 often have parts of the same or similar colors. However, because the image sensor 11 separates and records the color of the subject into R, G, and B components using the R, G, and B pixels, the signal values ​​of adjacent pixels rarely become the same or similar values.

[0043] As described above, the video signal transmission device 10 of this embodiment rearranges the RAW data output from the image sensor 11 so that pixel data of the same color are consecutive, so that the signal values ​​of adjacent pixels tend to be the same or close to each other.

[0044] In addition, the video signal transmitting device 10 of the present embodiment converts the digital data, after rearranging the pixel data of the same color so that they are consecutive, into an analog signal, so that high frequency components in the analog signal can be reduced.

[0045] This makes it possible to transmit RAW data with minimal degradation in image quality when transmitting the data in an analog manner.

[0046] [Variations] Although the video signal transmitting and receiving system 1 according to one embodiment of the present disclosure has been described above, the present disclosure is not limited to the above embodiment and can be modified as appropriate.

[0047] For example, the arrangement pattern of the pixels of the imaging element 11 is not limited to the pattern shown in FIG. 2 described above, and other patterns may be used.

[0048] For example, for an RGGB Bayer array having two lines per cycle in the vertical direction and two lines per cycle in the horizontal direction, as in the case of the imaging element 11a shown in Figure 4, the patterns of adjacent Bayer arrays in the vertical and horizontal directions may be inverted left to right.

[0049] In addition, the arrangement pattern of the pixels of the imaging element 11 may be any pattern in which pixels of multiple colors are arranged on the same line, such as an arrangement of three lines in one period in the vertical direction and three lines in one period in the horizontal direction.

[0050] In addition, in the above embodiment, the conversion unit 12 rearranges the pixel data so that pixel data of the same color occurs consecutively for every two horizontal lines, which is the period of the Bayer array in the vertical direction. However, the conversion unit 12 may rearrange the pixel data so that pixel data of the same color occurs consecutively for every horizontal line that is an integer multiple of the period of the Bayer array in the vertical direction.

[0051] In addition, in the above embodiment, the conversion unit 12 rearranges the pixel data for all pixels in a horizontal line so that pixel data of the same color are consecutive, but the conversion unit 12 may rearrange the pixel data for every portion of pixel data in a horizontal line, that is, for every integer multiple of the period of the Bayer array in the horizontal direction, so that pixel data of the same color are consecutive.

[0052] In addition to the above, appropriate modifications may be made to the description and illustrations shown above, such as deleting unnecessary parts, adding new elements, or making substitutions, within the scope of the gist of the technology disclosed herein.

[0053] [Note] Preferred embodiments of the present disclosure will be described below.

[0054] (Appendix 1) an image sensor having pixels of multiple colors arranged in the same line, the image sensor outputting RAW data generated by capturing an image; a conversion unit that rearranges pixel data for each of a plurality of lines in a first direction of the RAW data output from the imaging element so that pixel data of the same color are consecutive; a digital-to-analog conversion unit that converts the digital data converted by the conversion unit into an analog signal; a transmitting unit that transmits the analog signal converted by the digital-to-analog converter; A video signal transmitting device comprising:

[0055] (Appendix 2) The imaging element has pixels of multiple colors arranged in a Bayer array, The conversion unit rearranges the pixel data so that pixel data of the same color are consecutive for each line in the first direction, the number of lines being an integer multiple of a period of a Bayer array in a second direction perpendicular to the first direction. 2. A video signal transmission device as described in appendix 1.

[0056] (Appendix 3) The conversion unit rearranges the pixel data so that pixel data of the same color are consecutive for each line in the first direction, the number of which corresponds to one period of a Bayer array in the second direction. 3. A video signal transmission device as described in appendix 2.

[0057] (Appendix 4) The conversion unit rearranges pixel data for each part of pixel data in a line in the first direction, for every pixel data of an integer multiple of a period of a Bayer array in the first direction, such that pixel data of the same color are consecutive. 4. A video signal transmitting device according to claim 2 or 3.

[0058] (Appendix 5) A synchronization signal generating unit that generates a synchronization signal, the conversion unit has a storage unit that stores the RAW data output from the image sensor for each of a plurality of lines in the first direction, and continuously and sequentially reads out pixel data of the same color from the storage unit and outputs the data as digital data for each line; The digital-to-analog conversion unit converts the digital data, which is a combination of the digital data output from the conversion unit and the synchronous signal generated by the synchronous signal generation unit, into an analog signal. A video signal transmission device according to any one of appendix 2 to 4.

[0059] (Appendix 6) an array of pixels of the imaging element is a Bayer array in which one period in the second direction is two lines, and the Bayer array is made up of four pixels, a red pixel, a green pixel, a green pixel, and a blue pixel; The conversion unit rearranges the pixel data of the red pixels and the blue pixels in the Bayer array so that pixel data of the same color are continuous, and outputs the pixel data as digital data of one of the two lines, and rearranges the pixel data of the green pixels in the Bayer array in the arrangement order of the first direction, and outputs the pixel data as digital data of the other of the two lines. 6. A video signal transmission device as described in appendix 5.

[0060] (Appendix 7) A receiving unit for receiving an analog signal transmitted from the video signal transmitting device according to any one of claims 1 to 6; an analog-to-digital converter that converts the analog signal received by the receiver into digital data; an inverse conversion unit that inversely converts the digital data output from the analog-to-digital conversion unit into a color sequence of RAW data output from the image sensor for each line in the first direction; A video signal receiving device comprising:

[0061] (Appendix 8) A video signal transmission device according to any one of appendix 1 to 6, A video signal receiving device according to claim 7; A video signal transmitting and receiving system comprising: [Explanation of symbols]

[0062] 1. Video signal transmission and reception system 10. Video signal transmitter 11, 11a Image sensor 12 Conversion section 13 Synchronization signal generator 14 Synthesis section 15 DAC 16 Transmitter 20 Video signal receiving device 21 Receiving section 22 ADC 23 Inverse conversion section 31 Line even / odd judgement circuit 32 Line memory for odd lines 32 Line memory for even lines 33 Line memory for odd lines 34 Data read circuit 35 Data read control circuit

Claims

1. an image sensor having pixels of a plurality of colors arranged in the same line, the image sensor outputting raw data generated by capturing an image; a conversion unit that rearranges pixel data for each of a plurality of lines in a first direction of the RAW data output from the imaging element so that pixel data of the same color are consecutive; a digital-to-analog conversion unit that converts the digital data converted by the conversion unit into an analog signal; a transmitting unit that transmits the analog signal converted by the digital-to-analog converter; A video signal transmitting device comprising:

2. The imaging element has pixels of multiple colors arranged in a Bayer array, The conversion unit rearranges the pixel data so that pixel data of the same color are consecutive for each line in the first direction, the number of lines being an integer multiple of a period of a Bayer array in a second direction perpendicular to the first direction.

2. A video signal transmitting device according to claim 1.

3. The conversion unit rearranges the pixel data so that pixel data of the same color are continuous for each line in the first direction, the number of which corresponds to one period of a Bayer array in the second direction.

3. A video signal transmitting device according to claim 2.

4. The conversion unit rearranges pixel data for each part of pixel data in a line in the first direction, for every pixel data of an integer multiple of a period of a Bayer array in the first direction, such that pixel data of the same color are consecutive.

3. A video signal transmitting device according to claim 2.

5. A synchronization signal generating unit that generates a synchronization signal, the conversion unit has a storage unit that stores the RAW data output from the image sensor for each of a plurality of lines in the first direction, and continuously and sequentially reads out pixel data of the same color from the storage unit and outputs the data as digital data for each line; The digital-to-analog conversion unit converts the digital data, which is a combination of the digital data output from the conversion unit and the synchronous signal generated by the synchronous signal generation unit, into an analog signal.

3. A video signal transmitting device according to claim 2.

6. an array of pixels of the imaging element is a Bayer array in which one period in the second direction is two lines, and the Bayer array is made up of four pixels, a red pixel, a green pixel, a green pixel, and a blue pixel; The conversion unit rearranges pixel data of red pixels and blue pixels in the Bayer array so that pixel data of the same color are continuous, and outputs the pixel data as digital data of one of two lines, and rearranges pixel data of green pixels in the Bayer array in the arrangement order of the first direction, and outputs the pixel data as digital data of the other of the two lines.

6. A video signal transmitting device according to claim 5.

7. a receiving section for receiving an analog signal transmitted from the video signal transmitting device according to claim 1; an analog-to-digital converter that converts the analog signal received by the receiver into digital data; an inverse conversion unit that inversely converts the digital data output from the analog-to-digital conversion unit into a color sequence of RAW data output from the image sensor for each line in the first direction; A video signal receiving device comprising:

8. A video signal transmitting device according to claim 1 ; A video signal receiving device according to claim 7; A video signal transmitting and receiving system comprising:

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