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

Abstract

Provided are a video signal transmission device, a video signal reception device, and a video signal transmission / reception system with which degradation of image quality is suppressed in the case of analog transmission of RAW data. An imaging element in which pixels of a plurality of colors are arranged on the same line is provided with: an imaging element that outputs RAW data generated by imaging; a conversion unit that, for RAW data output from the imaging element, rearranges pixel data such that pixel data of the same color is continuous for each of a plurality of lines in the first direction; a digital-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-analog conversion unit.

Description

Technical Field

[0001] The present disclosure relates to an image signal sending device, an image signal receiving device, and an image signal sending and receiving system. Background Art

[0002] Patent Document 1 describes converting RAW data output from an image sensor into YC (Luminance / Chrominance) data. 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).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2004-088295 Summary of the invention

[0006] Problem that the invention aims to solve

[0007] In recent years, there has been a demand to transmit RAW data output from an image pickup element by analog transmission which is cheaper than digital transmission.

[0008] However, when RAW data is directly converted into analog grayscale voltages, the spectrum components thereof are wide-band, so there is a problem that image quality is easily degraded in a transmission circuit, a transmission path, or a reception circuit during transmission.

[0009] In view of the above circumstances, an object of the present disclosure is to provide an image signal transmitting apparatus, an image signal receiving apparatus, and an image signal transmitting and receiving system that suppress image quality degradation when RAW data is transmitted in analog form.

[0010] Solutions for solving problems

[0011] The image signal sending device disclosed in the present invention comprises: an imaging element, which arranges pixels of multiple colors on the same line and outputs RAW data generated by shooting; a conversion unit, which rearranges the pixel data of the RAW data output from the imaging element in each of multiple lines in a first direction so that pixel data of the same color are continuous; a digital-to-analog conversion unit, which converts the digital data converted by the conversion unit into an analog signal; and a sending unit, which sends the analog signal converted by the digital-to-analog conversion unit.

[0012] The image signal receiving device disclosed in the present invention comprises: a receiving unit, which receives an analog signal sent from the image signal sending device disclosed in the present invention; an analog-to-digital conversion unit, which converts the analog signal received by the receiving unit into digital data; and an inverse conversion unit, which inversely converts the digital data output from the analog-to-digital conversion unit into the color arrangement of the RAW data output by the camera element for each line in the first direction.

[0013] The video signal transmission and reception system of the present disclosure includes: the video signal transmission device of the present disclosure; and the video signal reception device of the present disclosure.

[0014] Effects of the Invention

[0015] According to the video signal transmission device of the present disclosure, when RAW data is transmitted in analog form, it is possible to transmit the data while suppressing degradation of image quality.

[0016] According to the video signal receiving device of the present disclosure, when RAW data is transmitted in analog form, it is possible to receive an analog signal with suppressed image quality degradation.

[0017] According to the video signal transmission and reception system of the present disclosure, when RAW data is transmitted in analog form, transmission and reception can be performed while suppressing degradation of image quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a diagram showing a schematic structure of a video signal transmission and reception system according to one embodiment of the present disclosure.

[0019] Figure 2 A diagram showing a schematic structure of an imaging element.

[0020] Figure 3 This is a diagram for explaining processing during analog signal transmission in a video signal transmitting device.

[0021] Figure 4 A diagram showing a schematic structure of an imaging element. DETAILED DESCRIPTION

[0022] Next, embodiments of the present disclosure will be described based on the drawings. Figure 1 This is a diagram showing a schematic structure of a video signal transmission and reception system according to one embodiment of the present disclosure. Figure 2 A diagram showing a schematic structure of an imaging element.

[0023] like Figure 1 As shown, the video signal transmission and reception system 1 of the present embodiment includes a video signal transmission device 10 and a video signal reception device 20 .

[0024] The video signal transmitting device 10 includes an imaging element 11, a converting unit 12, a synchronization signal generating unit 13, a synthesizing unit 14, a DAC (Digital to Analog Converter) 15, and a transmitting unit 16. The DAC 15 is an example of a digital to analog converter in the technology disclosed herein.

[0025] The image sensor 11 arranges pixels of a plurality of colors on the same line in the horizontal direction, and outputs RAW data generated by capturing images. The horizontal direction is an example of a first direction in the technology disclosed herein.

[0026] like Figure 2 As shown, the imaging element 11 of this embodiment has three color pixels, red, green, and blue, arranged in a Bayer arrangement. In addition, the red pixel is sometimes recorded as pixel R, the green pixel is recorded as pixel G, and the blue pixel is recorded as pixel B below.

[0027] The Bayer arrangement has two lines in one period in the vertical direction and two lines in one period in the horizontal direction, forming a Bayer arrangement consisting of four pixels: a first horizontal line consisting of pixels R and pixels G, and a second horizontal line consisting of pixels G and pixels B.

[0028] return Figure 1 The conversion unit 12 performs processing on the RAW data output from the image sensor 11 to rearrange the pixel data in each of a plurality of lines in the horizontal direction so that the pixel data of the same color are continuous.

[0029] The synchronization signal generating unit 13 generates a synchronization signal for performing analog transmission.

[0030] The synthesizing unit 14 generates digital data by synthesizing the digital data output from the converting unit 12 and the synchronization signal generated by the synchronization signal generating unit 13 .

[0031] The DAC 15 converts the digital data converted by the converter 12 into an analog signal. Specifically, the DAC 15 converts the digital data obtained by combining the digital data output from the converter 12 and the synchronization signal generated by the synchronization signal generator 13 by the synthesizer 14 into an analog signal.

[0032] The transmission unit 16 transmits the analog signal converted by the DAC 15 .

[0033] 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 disclosed herein.

[0034] The receiving unit 21 receives an analog signal transmitted from the image 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 arrangement of the RAW data output from the imaging element 11 for each horizontal line.

[0035] Next, use Figure 3 The following describes processing during analog signal transmission in the video signal transmitting device 10 of the video signal transmitting and receiving system 1 according to the present embodiment.

[0036] The video signal transmitting device 10 of the present embodiment directly converts RAW data into an analog signal and transmits the analog signal.

[0037] The frequency band of a general component signal (analog signal) including a luminance signal and a color difference signal is determined by the resolution of an input image.

[0038] In contrast, when RAW data is directly converted into an analog signal, the pixel value must be directly converted into the analog signal, so the signal band of the image becomes wider and the amplitude becomes larger. Therefore, a very high-performance DAC is required in circuit design, which is not practical.

[0039] In order to solve such a problem, the video signal transmitting device 10 of the present embodiment performs the following processing when directly converting RAW data into an analog signal.

[0040] like Figure 3 As shown, the conversion unit 12 includes a line even-odd determination circuit 31, an even-line line memory 32, an odd-line line memory 33, a data read circuit 34, and a data read control circuit 35. The even-line line memory 32 and the odd-line line memory 33 are examples of a storage unit in the technology disclosed herein.

[0041] The conversion unit 12 rearranges the pixel data in such a manner that pixel data of the same color continues for each of two lines in the horizontal direction, which is a period of the Bayer arrangement in the vertical direction.

[0042] Specifically, regarding the RAW data output from the camera element 11, the line even-odd judgment circuit 31 judges whether each line in the horizontal direction is an even line or an odd line, and in the case of an even line, it is stored in the line memory 32 for even lines, and in the case of an odd line, it is stored in the line memory 33 for odd lines.

[0043] The data reading control circuit 35 controls the data reading circuit 34 to 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 outputs the pixel data as digital data for each line to the subsequent stage.

[0044] Specifically, the data reading control circuit 35 rearranges the pixel data of the pixel R and the pixel B in the Bayer arrangement in such a manner that the pixel data of the same color are continuous, and outputs the pixel data as the digital data of the Nth line, and rearranges the pixel data of the pixel G in the Bayer arrangement in the horizontal arrangement order, and outputs the pixel data as the digital data of the N+1th line.

[0045] exist Figure 3 In the example of , in the imaging element 11, as pixels of the Nth line, pixels R1, pixel G2, pixel R2, and pixel G4 are arranged in order from the left, and as pixels of the N+1th line, pixels G1, pixel B1, pixel G3, and pixel B2 are arranged in order from the left. In addition, although not shown in the figure, in the imaging element 11, in addition to the above-mentioned pixels, pixels of the same arrangement pattern are periodically arranged in both the horizontal direction and the vertical direction.

[0046] The RAW data of the Nth line output from the imaging element 11 is stored in the even-numbered line memory 32 through the line even-odd determination circuit 31 , and the RAW data of the N+1th line output from the imaging element 11 is stored in the odd-numbered line memory 33 through the line even-odd determination circuit 31 .

[0047] The data reading control circuit 35 controls the data reading circuit 34 to rearrange the pixel data in the order of pixel R1 , pixel R2 , pixel B1 , and pixel B2 from the beginning, and outputs the pixel data as digital data of the Nth line.

[0048] In addition, the data reading control circuit 35 controls the data reading circuit 34 to rearrange the pixel data in the order of pixel G1, pixel G2, pixel G3, and pixel G4 from the beginning, and outputs it as digital data of the N+1th line.

[0049] The synthesizing unit 14 generates digital data by synthesizing the digital data output from the converting unit 12 and the synchronization signal generated by the synchronization signal generating unit 13. The DAC 15 converts the digital data generated by the synthesizing unit 14 into an analog signal.

[0050] Most of the subjects such as people or scenery photographed by the imaging element 11 are locally concentrated with the same color or similar colors. However, in the imaging element 11, the color of the subject is separated into R component, G component, and B component by pixels R, G, and B and recorded, so the signal values ​​of adjacent pixels are rarely the same or close to each other.

[0051] As described above, the video signal transmitting device 10 of the present embodiment rearranges the RAW data output from the imaging element 11 so that pixel data of the same color continues. Therefore, the signal values ​​of adjacent pixels tend to be the same value or close values.

[0052] Furthermore, the video signal transmitting device 10 of the present embodiment converts the digital data rearranged so that pixel data of the same color continues into an analog signal, and thus can reduce high-frequency components in the analog signal.

[0053] This makes it possible to transmit RAW data while suppressing image quality degradation when performing analog transmission.

[0054] [Modifications]

[0055] As mentioned above, the video signal transmission and reception system 1 according to one embodiment of the present disclosure has been described. However, the present disclosure is not limited to the above embodiment, and can be modified as appropriate.

[0056] For example, the arrangement pattern of the pixels of the imaging element 11 is not limited to the above-described Figure 2 The pattern shown can also be set to other patterns.

[0057] For example, it can also be set as Figure 4 As shown in the image pickup element 11a, for an RGGB Bayer arrangement in which one period in the vertical direction is two lines and one period in the horizontal direction is two lines, the patterns of the Bayer arrangements adjacent to each other in the vertical and horizontal directions are reversed left and right.

[0058] The pixel arrangement pattern of the imaging element 11 may be any pattern as long as pixels of multiple colors are arranged on the same line, for example, three lines in one period in the vertical direction and three lines in one period in the horizontal direction.

[0059] In addition, in the above-mentioned embodiment, the conversion unit 12 is set to rearrange the pixel data in a manner such that pixel data of the same color are continuous for each of the horizontal lines whose number is two lines as the period of the Bayer arrangement in the vertical direction, but it may also be set to rearrange the pixel data in a manner such that pixel data of the same color are continuous for each of the horizontal lines whose number is an integer multiple of the period of the Bayer arrangement in the vertical direction.

[0060] In addition, in the above-mentioned embodiment, the conversion unit 12 is set to rearrange the pixel data for all pixels on the horizontal line in a manner such that pixel data of the same color are continuous, but it can also be set to rearrange the pixel data for each pixel data in a part of the pixel data on the horizontal line, that is, each pixel data of a number of pixel data that is an integer multiple of the period of the Bayer arrangement in the horizontal direction in a manner such that pixel data of the same color are continuous.

[0061] In addition to the above, the descriptions and illustrations described above may be modified as appropriate, such as deleting unnecessary parts, adding new elements, or replacing them, without departing from the technical spirit of the present disclosure.

[0062] [Note]

[0063] Preferred embodiments of the present disclosure are described below.

[0064] (Note 1)

[0065] An image signal sending device, comprising:

[0066] An imaging element that has pixels of multiple colors arranged on the same line and outputs RAW data generated by shooting;

[0067] a conversion unit for rearranging pixel data in a manner that pixel data of the same color are continuous for each of a plurality of lines in a first direction with respect to the RAW data output from the imaging element;

[0068] a digital-to-analog converter that converts the digital data converted by the converter into an analog signal; and

[0069] A transmitting unit transmits the analog signal converted by the digital-to-analog converter.

[0070] (Note 2)

[0071] The image signal transmitting device according to Supplement 1, wherein:

[0072] The image sensor arranges pixels of multiple colors in a Bayer arrangement.

[0073] The conversion section rearranges the pixel data in such a manner that pixel data of the same color continues, for each of the lines in the first direction whose number is an integral multiple of a period of the Bayer arrangement in a second direction orthogonal to the first direction.

[0074] (Note 3)

[0075] The video signal transmitting device according to Supplement 2, wherein:

[0076] The conversion unit rearranges the pixel data in each of the lines in the first direction, the number of which corresponds to one period of the Bayer arrangement in the second direction, so that the pixel data of the same color continues.

[0077] (Note 4)

[0078] The video signal transmitting device according to Appendix 2 or 3, wherein:

[0079] The conversion unit rearranges the pixel data in a portion of the pixel data in the line in the first direction, that is, in a number of pixel data that is an integral multiple of the period of the Bayer arrangement in the first direction, so that pixel data of the same color continues.

[0080] (Note 5)

[0081] The video signal transmitting device according to any one of Supplements 2 to 4, wherein:

[0082] A synchronization signal generating unit is provided for generating a synchronization signal,

[0083] The conversion unit includes a storage unit for storing RAW data output from the imaging element for each of a plurality of lines in the first direction, and sequentially reads pixel data of the same color from the storage unit and outputs the data as digital data for each line.

[0084] The digital-to-analog converter converts digital data obtained by combining the digital data output from the converter and the synchronization signal generated by the synchronization signal generator into an analog signal.

[0085] (Note 6)

[0086] The video signal transmitting device according to Supplement 5, wherein:

[0087] The pixel arrangement of the imaging element is a Bayer arrangement in which one cycle of the Bayer arrangement in the second direction is two lines and the arrangement is composed of four pixels, namely, a red pixel, a green pixel, a green pixel, and a blue pixel.

[0088] The conversion unit rearranges the pixel data of red pixels and blue pixels in the Bayer arrangement in such a way 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 green pixels in the Bayer arrangement in the arrangement order of the first direction and outputs the pixel data as digital data of the other of the two lines.

[0089] (Note 7)

[0090] An image signal receiving device, comprising:

[0091] a receiving unit for receiving an analog signal transmitted from the image signal transmitting device according to any one of Supplementary Notes 1 to 6;

[0092] an analog-to-digital converter that converts the analog signal received by the receiving unit into digital data; and

[0093] An inverse conversion section inversely converts the digital data output from the analog-to-digital conversion section into a color arrangement of the RAW data output from the imaging element for each line in the first direction.

[0094] (Note 8)

[0095] An image signal sending and receiving system, comprising:

[0096] The image signal transmitting device according to any one of Supplementary Notes 1 to 6; and

[0097] An image signal receiving device according to Appendix 7.

[0098] Description of Reference Numerals

[0099] 1: Image signal sending and receiving system; 10: Image signal sending device; 11, 11a: Image sensor; 12: Conversion unit; 13: Synchronous signal generating unit; 14: Synthesis unit; 15: DAC; 16: Sending unit; 20: Image signal receiving device; 21: Receiving unit; 22: ADC; 23: Inverse conversion unit; 31: Line even-odd determination circuit; 32: Line memory for odd lines; 32: Line memory for even lines; 33: Line memory for odd lines; 34: Data reading circuit; 35: Data reading control circuit.

Claims

1. An image signal sending device, comprising: An imaging element that has pixels of multiple colors arranged on the same line and outputs RAW data generated by shooting; a conversion unit for rearranging pixel data in a manner that pixel data of the same color are continuous for each of a plurality of lines in a first direction with respect to the RAW data output from the imaging element; a digital-to-analog converter that converts the digital data converted by the converter into an analog signal; and A transmitting unit transmits the analog signal converted by the digital-to-analog converter.

2. The image signal transmitting device according to claim 1, wherein: The image sensor arranges pixels of multiple colors in a Bayer arrangement. The conversion section rearranges the pixel data in such a manner that pixel data of the same color continues, for each of the lines in the first direction whose number is an integral multiple of a period of the Bayer arrangement in a second direction orthogonal to the first direction.

3. The video signal transmitting device according to claim 2, wherein: The conversion unit rearranges the pixel data in each of the lines in the first direction, the number of which corresponds to one period of the Bayer arrangement in the second direction, so that the pixel data of the same color continues.

4. The image signal transmitting device according to claim 2, wherein: The conversion unit rearranges the pixel data in a portion of the pixel data in the line in the first direction, that is, in a number of pixel data that is an integral multiple of the period of the Bayer arrangement in the first direction, so that pixel data of the same color continues.

5. The image signal transmitting device according to claim 2, wherein: A synchronization signal generating unit is provided for generating a synchronization signal, The conversion unit includes a storage unit for storing RAW data output from the imaging element for each of a plurality of lines in the first direction, and sequentially reads pixel data of the same color from the storage unit and outputs the data as digital data for each line. The digital-to-analog converter converts digital data obtained by combining the digital data output from the converter and the synchronization signal generated by the synchronization signal generator into an analog signal.

6. The video signal transmitting device according to claim 5, wherein: The pixel arrangement of the imaging element is a Bayer arrangement in which one cycle of the Bayer arrangement in the second direction is two lines and the arrangement is composed of four pixels, namely, a red pixel, a green pixel, a green pixel, and a blue pixel. The conversion unit rearranges the pixel data of red pixels and blue pixels in the Bayer arrangement in such a way 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 green pixels in the Bayer arrangement in the arrangement order of the first direction and outputs the pixel data as digital data of the other of the two lines.

7. An image signal receiving device, comprising: a receiving unit 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 receiving unit into digital data; and An inverse conversion section inversely converts the digital data output from the analog-to-digital conversion section into a color arrangement of the RAW data output from the imaging element for each line in the first direction.

8. An image signal sending and receiving system, comprising: The image signal transmitting device according to claim 1; and The image signal receiving device according to claim 7.

Images