# US 10,313,579 B2 · Dual phase detection auto focus camera sensor data processing > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,313,579 B2 - Document ID: US10313579B2 - Status: Granted - Kind: B2 - Application number: 15/693,078 - Filed: 2017-08-31 - Published: 2019-02-28 - Granted: 2019-06-04 - Earliest claimed: 2017-08-31 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Ravi Shankar Kadambala; Soman Nikhara; Bapineedu Chowdary Gummadi - Web page: https://patentgrep.com/patent/US10313579B2 ## CPC - H04N 23/67: Focus control based on electronic image sensor signals - G03B 13/36: Autofocus systems - H04N 23/55: Optical parts specially adapted for electronic image sensors; Mounting thereof - H04N 25/703: SSIS architectures incorporating pixels for producing signals other than image signals - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION - G03B: APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR (optical parts of such apparatus G02B; photosensitive materials or processes for photographic purposes G03C; apparatus for processing exposed photographic materials G03D) ## Abstract A method of image processing includes capturing two frames of image data using a camera having a phase detection auto focus (PDAF) sensor, subtracting phase difference pixel data associated with the two frames of image data to produce residual phase difference values, detecting a region-of-interest change based on the residual phase differences values, and determining a focus for the PDAF camera sensor based on the detected region-of-interest change. The method may further include compressing the residual phase difference values, sending the compressed residual phase difference values to a processor, and reconstructing, with the processor, the phase difference pixel data from the compressed residual phase difference values. ## Claims ### Claim 1 A method of image processing, the method comprising: receiving residual phase difference values from a phase detection auto focus (PDAF) sensor of a camera, the residual phase difference values resulting from subtracting phase difference pixel data associated with two frames of image data; detecting a region-of-interest change based on the residual phase differences values; and determining a focus for the camera based on the detected region-of-interest change. ### Claim 2 (depends on 1) The method of claim 1, wherein the two frames of image data include a first frame of image data and a second frame of image data, the method further comprising: capturing the first frame of image data with the PDAF sensor; calculating first phase difference pixel data from the first frame of image data; capturing the second frame of image data with the PDAF sensor; and calculating second phase difference pixel data from the second frame of image data. ### Claim 3 (depends on 2) The method of claim 2, further comprising: subtracting the second phase difference pixel data from the first phase difference pixel data to produce the residual phase difference values; compressing the residual phase difference values; sending the compressed residual phase difference values to a processor; and reconstructing, with the processor, the second phase difference pixel data from the compressed residual phase difference values. ### Claim 4 (depends on 3) The method of claim 3, wherein compressing the residual phase difference values comprises run-length encoding the residual phase difference values. ### Claim 5 (depends on 3) The method of claim 3, further comprising: determining the focus for the camera based on the reconstructed second phase difference pixel data. ### Claim 6 (depends on 5) The method of claim 5, further comprising: determining a lens position based on the determined focus; sending information indicating the lens position to the PDAF sensor; and adjusting a lens of the camera based on the information indicating the lens position. ### Claim 7 (depends on 6) The method of claim 6, further comprising: capturing an image using the adjusted lens of the camera; and outputting the captured image to a memory. ### Claim 8 (depends on 1) The method of claim 1, wherein the two frames of image data are one of two frames of still image data or two frames of video data. ### Claim 9 An apparatus configured for image processing, the apparatus comprising: a memory configured to store image data; and a processor in communication with the PDAF sensor, the processor configured to: receive residual phase difference values associated with the image data from a phase detection auto focus (PDAF) sensor of a camera, the residual phase difference values resulting from subtracting phase difference pixel data associated with the two frames of image data; detect a region-of-interest change based on the residual phase differences values; and determine a focus for the camera based on the detected region-of-interest change. ### Claim 10 (depends on 9) The apparatus of claim 9, wherein the two frames of image data include a first frame of image data and a second frame of image data, the apparatus further comprising the camera having the PDAF sensor, the PDAF sensor configured to: capture the first frame of image data; calculate first phase difference pixel data from the first frame of image data; capture the second frame of image data; and calculate second phase difference pixel data from the second frame of image data. ### Claim 11 (depends on 10) The apparatus of claim 10, wherein the PDAF sensor is further configured to: subtract the second phase difference pixel data from the first phase difference pixel data to produce the residual phase difference values; compress the residual phase difference values; and send the compressed residual phase difference values to the processor, and wherein the processor is further configured to: reconstruct the second phase difference pixel data from the compressed residual phase difference values. ### Claim 12 (depends on 11) The apparatus of claim 11, wherein to compress the residual phase difference values, the PDAF sensor is further configured to run-length encode the residual phase difference values. ### Claim 13 (depends on 11) The apparatus of claim 11, wherein the processor is further configured to: determine the focus for the camera based on the reconstructed second phase difference pixel data. ### Claim 14 (depends on 13) The apparatus of claim 13, wherein the processor is further configured to: determine a lens position based on the determined focus; and send information indicating the lens position to the PDAF sensor, and wherein the PDAF sensor is further configured to: adjust a lens of the camera based on the information indicating the lens position. ### Claim 15 (depends on 14) The apparatus of claim 14, wherein the PDAF sensor is further configured to: capture an image using the adjusted lens; and output the captured image to a memory. ### Claim 16 (depends on 10) The apparatus of claim 10, wherein the two frames of image data are one of two frames of still image data or two frames of video data. ### Claim 17 (depends on 10) The apparatus of claim 10, wherein the PDAF sensor includes a plurality of dual photodiode pixel sensors. ### Claim 18 (depends on 10) The apparatus of claim 10, wherein the PDAF sensor is one of a type 2 PDAF or a type 3 PDAF sensor. ### Claim 19 (depends on 9) The apparatus of claim 9, wherein the processor is an image signal processor. ### Claim 20 (depends on 9) The apparatus of claim 9, wherein the apparatus of one of a mobile device, a mobile telephone, a tablet computer, a laptop computer, a digital camera, or a digital video recorder. ### Claim 21 An apparatus configured for image processing, the apparatus comprising: means for receiving residual phase difference values from a phase detection auto focus (PDAF) sensor of a camera, the residual phase difference values resulting from subtracting phase difference pixel data associated with two frames of image data to produce residual phase difference values; means for detecting a region-of-interest change based on the residual phase differences values; and means for determining a focus based on the detected region-of-interest change. ### Claim 22 (depends on 21) The apparatus of claim 21, wherein the two frames of image data include a first frame of image data and a second frame of image data, the apparatus further comprising: means for capturing the first frame of image data; means for calculating first phase difference pixel data from the first frame of image data; means for capturing the second frame of image data; and means for calculating second phase difference pixel data from the second frame of image data. ### Claim 23 (depends on 22) The apparatus of claim 22, further comprising: means for subtracting the second phase difference pixel data from the first phase difference pixel data to produce the residual phase difference values; means for compressing the residual phase difference values; means for sending the compressed residual phase difference values to a processor; and means for reconstructing, with the processor, the second phase difference pixel data from the compressed residual phase difference values. ### Claim 24 (depends on 23) The apparatus of claim 23, further comprising: means for determining the focus based on the reconstructed second phase difference pixel data. ### Claim 25 (depends on 24) The apparatus of claim 24, further comprising: means for determining a lens position based on the determined focus; means for sending information indicating the lens position; and means for adjusting a lens based on the information indicating the lens position. ### Claim 26 A non-transitory computer-readable storage medium storing instructions that, when executed, causes one or more processor to: receive residual phase difference values from a phase detection auto focus (PDAF) sensor of a camera, the residual phase difference values resulting from subtracting phase difference pixel data associated with two frames of image data to produce residual phase difference values; detect a region-of-interest change based on the residual phase differences values; and determine a focus for the camera based on the detected region-of-interest change. ### Claim 27 (depends on 26) The non-transitory computer-readable storage medium of claim 26, wherein the two frames of image data include a first frame of image data and a second frame of image data, and wherein the instructions further cause the one or more processor to: capture the first frame of image data with the PDAF sensor; calculate first phase difference pixel data from the first frame of image data; capture the second frame of image data with the PDAF sensor; and calculate second phase difference pixel data from the second frame of image data. ### Claim 28 (depends on 27) The non-transitory computer-readable storage medium of claim 27, wherein the instructions further cause the one or more processors to: subtract the second phase difference pixel data from the first phase difference pixel data to produce the residual phase difference values; compress the residual phase difference values; send the compressed residual phase difference values to a processor; and reconstruct, with the processor, the second phase difference pixel data from the compressed residual phase difference values. ### Claim 29 (depends on 28) The non-transitory computer-readable storage medium of claim 28, wherein the instructions further cause the one or more processor to: determine the focus for the camera based on the reconstructed second phase difference pixel data. ### Claim 30 (depends on 29) The non-transitory computer-readable storage medium of claim 29, wherein the instructions further cause the one or more processor to: determine a lens position based on the determined focus; send information indicating the lens position to the PDAF sensor; and adjust a lens of the camera based on the information indicating the lens position.