Video imaging system with image processing optimized for small-diameter endoscopes
First Claim
1. A method of deriving an output video signal from an input video signal generated by an image sensor having an image formed on only a part thereof, the output video signal being derived in response to only a portion of the input video signal generated by the part of the image sensor whereon the image is formed, the input video signal additionally including a portion generated by the part of the image sensor whereon the image is not formed, the method comprising steps of:
- providing an image signal generating apparatus wherein the image sensor is mounted, the image signal generating apparatus including a detachable image-forming device selectably attached thereto, the detachable image-forming device including a lens and a proximal fibre-optic bundle, and, when attached to the image signal generating apparatus, forming the image on the part of the image sensor, the image having a size and a position;
receiving a frame of the input video signal from the image sensor, the frame of the input video signal having a structure and including an image portion generated by the part of the image sensor on which the image is formed, and an external portion generated by the part of the image sensor on which the image is not formed;
identifying the image portion of the frame of the input video signal; and
extracting from the frame of the input video signal the image portion of the input video signal identified in the identifying step to provide an image portion of a frame the output signal, the frame of the output video signal having a structure substantially similar to the structure of the frame of the input video signal.
5 Assignments
0 Petitions
Accused Products
Abstract
An output video signal is derived from an input video signal generated by an image sensor in response to an image formed on only part of the image sensor. The output video signal is derived in response to only the portion of the input video signal generated by the part of the image sensor on which the image is formed. The input video signal additionally includes a portion generated by the part of the image sensor on which the image is not formed. An image signal generating apparatus is provided in which the image sensor is mounted, and which includes a detachably-attached image-forming device. When attached to the image signal generating apparatus, the image-forming device forms the image on the part of the image sensor. A frame of the input video signal is received from the image sensor. The frame of the input video signal has a structure and includes an image portion generated by the part of the image sensor on which the image is formed, and an external portion generated by the part of the image sensor on which the image is not formed. The image portion of the frame of the input video signal is identified, and the identified image portion is extracted from the frame of the input video signal to provide the image portion of a frame of the output signal which has a frame structure substantially similar to the frame structure of the input video signal.
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Citations
45 Claims
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1. A method of deriving an output video signal from an input video signal generated by an image sensor having an image formed on only a part thereof, the output video signal being derived in response to only a portion of the input video signal generated by the part of the image sensor whereon the image is formed, the input video signal additionally including a portion generated by the part of the image sensor whereon the image is not formed, the method comprising steps of:
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providing an image signal generating apparatus wherein the image sensor is mounted, the image signal generating apparatus including a detachable image-forming device selectably attached thereto, the detachable image-forming device including a lens and a proximal fibre-optic bundle, and, when attached to the image signal generating apparatus, forming the image on the part of the image sensor, the image having a size and a position; receiving a frame of the input video signal from the image sensor, the frame of the input video signal having a structure and including an image portion generated by the part of the image sensor on which the image is formed, and an external portion generated by the part of the image sensor on which the image is not formed; identifying the image portion of the frame of the input video signal; and extracting from the frame of the input video signal the image portion of the input video signal identified in the identifying step to provide an image portion of a frame the output signal, the frame of the output video signal having a structure substantially similar to the structure of the frame of the input video signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
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19. A method for generating an output video signal from an input video signal, position-dependent luminance errors in the input video signal being corrected in the output video signal, the input video signal being generated by an image sensor having an image formed on only a part thereof, the output video signal being derived in response to only a portion of the input video signal generated by the part of the image sensor whereon the image is formed, the input video signal additionally including a portion generated by the part of the image sensor whereon the image is not formed, the image including an image element having a position in the image, the method comprising steps of:
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receiving a frame of the input video signal from the image sensor, the frame of the input video signal having a structure and including an image portion generated by the part of the image sensor on which the image is formed, and an external portion generated by the part of the image sensor on which the image is not formed, the image portion of the input video signal including a signal element corresponding to the image element; identifying the image portion of the frame of the input video signal; extracting from the frame of the input video signal the image portion identified in the identifying step; multiplying the signal element of the image portion by a position-dependent function to provide a modified image portion, the position-dependent function depending on the position in the image of the image element; and incorporating the modified image portion in a frame the output video signal as an image portion thereof, the frame of the output video signal having a structure substantially similar to the structure of the frame of the input video signal. - View Dependent Claims (20, 21, 22, 23, 24, 25)
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26. A method for processing an input video signal generated by an image sensor having an image formed on only a part thereof to generate a control signal for controlling an automatic luminance system responsive to a level of the control signal averaged over a time corresponding to frames of the input video signal, the control signal being generated only in response to a portion of the input video signal generated by the part of the image sensor whereon the image is formed, the input video signal additionally including a portion generated by the part of the image sensor whereon the image is not formed, the method comprising steps of:
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receiving a frame of the input video signal from the image sensor, the frame of the input video signal having a structure and including an image portion generated by the part of the image sensor on which the image is formed, and an external portion generated by the part of the image sensor on which the image is not formed, the image portion having an average luminance; identifying the image portion of the frame of the input video signal; and deriving from the frame of the input video signal a frame of the control signal, the frame of the control signal having an average level corresponding to the average luminance of the image portion of the frame of the input video signal identified in the identifying step. - View Dependent Claims (27, 28, 29, 30, 31, 32, 33, 34, 35, 36)
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37. A method for deriving an output video signal from an input video signal generated by an image sensor having an image formed on only a part thereof, the output video signal being derived in response to only a portion of the input video signal generated by the part of the image sensor whereon the image is formed, the input video signal additionally including a portion generated by the part of the image sensor whereon the image is not formed, the output video signal having a lower noise level than the portion of the input video signal generated by the part of the image sensor whereon the image is formed, the method comprising steps of:
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providing a memory, the memory including pages, each of the pages including storage locations; receiving a frame of the input video signal from the image sensor, the frame of the input video signal having a structure, being divided into picture elements, and including an image portion generated by the part of the image sensor on which the image is formed, and an external portion generated by the part of the image sensor on which the image is not formed; identifying the image portion of each frame of the input video signal; storing the picture elements of the image portion, identified in the identifying step, of successive frames of the input video signal in corresponding ones of the memory locations in successive ones of the pages of the memory; averaging the picture elements of the image portion of the successive frames of the input video signal stored in the corresponding ones of the memory locations in the successive ones of the pages of the memory to provide average values; and generating an image portion of a frame of the output video signal from the average values provided by the averaging step, the frame of the output video signal having a structure substantially similar to the structure of the frame of the input video signal. - View Dependent Claims (38, 39, 40)
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41. A method for deriving an output video signal from an input video signal generated by an image sensor having an image formed on only a part thereof, the output video signal being derived in response to only a portion of the input video signal generated by the part of the image sensor whereon the image is formed, the input video signal additionally including a portion generated by the part of the image sensor whereon the image is not formed, the output video signal having a lower noise level than the portion of the input video signal generated by the part of the image sensor whereon the image is formed, and the method comprising steps of:
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receiving a frame of the input video signal from the image sensor, the frame of the input video signal having a structure and including an image portion generated by the part of the image sensor on which the image is formed, and an external portion generated by the part of the image sensor on which the image is not formed, the image portion of the frame of the input video signal being divided into picture elements, each of the picture elements having a sample value; identifying the image portion of the frame of the input video signal; providing a memory, the memory including storage locations, each of the storage locations corresponding to one of the picture elements of the image portion of the input video signal; reading an accumulated sample value for each one of the picture elements of the image portion of the input video signal from a respective one of the storage locations in the memory; multiplying the accumulated sample value read from the memory in the reading step by a degradation factor to provide a multiplied accumulated sample value; averaging the multiplied accumulated sample value provided by the multiplying step by the sample value of the one of the picture elements of the frame of the image portion of the input video signal identified in the identifying step to provide an average value, the one of the picture elements corresponding to the multiplied accumulated sample value; providing the average value provided in the averaging step as a sample value of a picture element of an image portion of the output video signal, the picture element of the image portion of the output video signal corresponding to the one of the picture elements of the input video signal, the frame of the output video signal having a structure substantially similar to the structure of the frame of the input video signal; and storing the average value provided in the averaging step in the one of the storage locations in the memory as the accumulated sample value for the one of the picture elements of the input video signal. - View Dependent Claims (42)
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43. An apparatus for deriving an output video signal from an input video signal generated by an image sensor having an image formed on only a part thereof, the output video signal being derived in response to only a portion of the input video signal generated by the part of the image sensor whereon the image is formed, the input video signal additionally including a portion generated by the part of the image sensor whereon the image is not formed, the apparatus comprising:
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an image signal generator wherein the image sensor is mounted, the image signal generator including an image-forming device detachably attached thereto, the image-forming device, when attached to the image signal generator, forming the image on part of the image sensor; a frame store memory means for storing one of a frame of the input video signal and a frame of the output video signal, the frame of the input video signal having a structure and including an image portion generated by the part of the image sensor on which the image is formed, and an external portion generated by the part of the image sensor on which the image is not formed; and a digital signal processor means, operating together with the frame store memory means, for; identifying the image portion of the frame of the input video signal in response to identification information; and extracting only the image portion identified by the identification information from the frame of the input video signal to provide an image portion of the frame of the output video signal, the frame of the output video signal having a structure substantially similar to the structure of the frame of the input video signal. - View Dependent Claims (44, 45)
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Specification