# US 10,504,466 B2 · Method, device and non-transitory computer-readable medium for control of refresh frequency of display unit > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,504,466 B2 - Document ID: US10504466B2 - Status: Granted - Kind: B2 - Application number: 15/860,992 - Filed: 2018-01-03 - Published: 2018-09-13 - Granted: 2019-12-10 - Earliest claimed: 2017-03-10 - Assignees: Guangdong Oppo Mobile Telecommunications Corp., Ltd. - Applicants: Guangdong Oppo Mobile Telecommunications Corp., Ltd. - Inventors: Deliang Peng; Yongpeng Yi; Shengjun Gou; Xiaori Yuan; Gaoting Gan; Zhiyong Zheng; Hai Yang - Web page: https://patentgrep.com/patent/US10504466B2 ## CPC - G09G 3/3618: {with automatic refresh of the display panel using sense/write circuits} - G09G 5/001: {Arbitration of resources in a display system, e.g. control of access to frame buffer by video controller and/or main processor} - G09G 5/003: {Details of a display terminal, the details relating to the control arrangement of the display terminal and to the interfaces thereto (specific for a CRT G09G1/165; for a flat panel G09G3/2092)} - G09G 5/18: Timing circuits for raster scan displays (specially adapted for television H04N {; synchronisation between the display unit and other display units, videodisc player G09G5/12}) - G09G 5/36: characterised by the display of a graphic pattern, e.g. using an all-points-addressable [APA] memory - G09G 5/363: {Graphics controllers} - G06F 3/14: Digital output to display device {; Cooperation and interconnection of the display device with other functional units} - G09G 5/399: using two or more bit-mapped memories, the operations of which are switched in time, e.g. ping-pong buffers - G09G 2320/08: Arrangements within a display terminal for setting, manually or automatically, display parameters of the display terminal - G09G 2320/103: Detection of image changes, e.g. determination of an index representative of the image change - G09G 2330/021: Power management, e.g. power saving - G09G 2340/0435: Change or adaptation of the frame rate of the video stream - G09G 2350/00: Solving problems of bandwidth in display systems - G09G 2360/08: Power processing, i.e. workload management for processors involved in display operations, such as CPUs or GPUs - G09G: ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION (arrangements for transferring data between digital computers and displays G06F3/14; static indicating arrangements comprising an association of a number of separate sources or light control cells G09F9/00; static indicating arrangements comprising integral associations of a number of light sources H01J, H01K, H10H, H05B33/12; scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission, details thereof H04N1/00) - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract A method, device and non-transitory computer-readable medium for control of a refresh frequency of a display unit are disclosed. The display unit is in communication with a processor and configured to display image frames processed by the processor on a screen of the display unit. The method includes: acquiring a real-time frame composition frequency corresponding to an amount of time required for the processor to complete composition of an image frame to be displayed; determining a refresh frequency of the display unit based on the real-time frame composition frequency, when the real-time-frame composition frequency satisfies a preset condition; and refreshing the screen of the display unit at the determined refresh frequency. ## Claims ### Claim 1 A method for control of a refresh frequency of a display unit, the display unit being in communication with a processor and configured to display image frames processed by the processor on a screen of the display unit, the method comprising: acquiring a frame composition frequency of image frames, wherein each of the image frames is composed from images rendered by various applications; determining a refresh frequency of the display unit based on the frame composition frequency, when the frame composition frequency is less than a preset maximum refresh frequency of the display unit; and refreshing the screen of the display unit at the determined refresh frequency; wherein acquiring the frame composition frequency of image frames comprises: acquiring time taken by the processor to complete composition of each of N successive image frames displayed immediately before performing the acquiring operation; and determining the frame composition frequency of the image frames according to the following formula: S = 1 / ∑ i = 1 N ⁢ ⁢ ( T i / N ) , where S is the frame composition frequency of the image frames, and Ti is time taken by the processor to complete composition of an i-th image frame among the N successive image frames displayed immediately before performing the acquiring operation. ### Claim 2 (depends on 1) The method of claim 1, further comprising: refreshing the screen of the display unit at the preset maximum refresh frequency, when the frame composition frequency is no less than the preset maximum refresh frequency of the display unit. ### Claim 3 (depends on 1) The method of claim 1, wherein determining the refresh frequency of the display unit based on the frame composition frequency comprises: determining the refresh frequency of the display unit based on a relationship between the frame composition frequency and a preset minimum refresh frequency and a relationship between the frame composition frequency and the preset maximum refresh frequency, when a sum of the frame composition frequency and a first preset value is less than the preset maximum refresh frequency. ### Claim 4 (depends on 3) The method of claim 3, wherein determining the refresh frequency of the display unit based on the relationship between the frame composition frequency and the preset minimum refresh frequency and the relationship between the frame composition frequency and the preset maximum refresh frequency comprises: setting the refresh frequency of the display unit as a sum of the frame composition frequency and a second preset value, when the sum of the frame composition frequency and the first preset value is greater than or equal to the preset minimum refresh frequency, wherein the sum of the frame composition frequency and the second preset value is less than the preset maximum refresh frequency; and setting the refresh frequency of the display unit as the preset minimum refresh frequency, when the sum of the frame composition frequency and the first preset value is less than the preset minimum refresh frequency. ### Claim 5 (depends on 4) The method of claim 4, wherein the first preset value is set as 0, and the second preset value is set as 2. ### Claim 6 (depends on 1) The method of claim 1, further comprising: in response to a system vertical synchronization signal transmitted by a display controller of the display unit, generating a interrupt to control rendering and composition operations of each image frame according to the system vertical synchronization signal. ### Claim 7 (depends on 6) The method of claim 6, further comprising: in response to a first system vertical synchronization signal transmitted by the display controller of the display unit, forwarding the first system vertical synchronization signal to a plurality of applications, wherein the first system vertical synchronization signal indicates each application to perform a rendering operation in response to a touch or drag manipulation on the screen, so as to obtain a plurality of images rendered by the plurality of applications respectively; in response to a second system vertical synchronization signal transmitted by the display controller of the display unit, forwarding the second system vertical synchronization signal to a surface flinger, wherein the second system vertical synchronization signal indicates the surface flinger to perform image composition operation of the plurality of images rendered by the plurality of applications respectively, so as to obtain the image frames to be displayed; and in response to a third system vertical synchronization signal transmitted by the display controller of the display unit, performing refreshing operation to display the image frames to be displayed on the screen of the display unit. ### Claim 8 (depends on 1) The method of claim 1, a running scene of a mobile terminal includes a static scene, a dynamic scene and a transition scene, each of the static scene, the dynamic scene and the transition scene corresponds to a refresh frequency of the display unit, wherein determining the refresh frequency of the display unit based on the frame composition frequency comprises: during transition from the static scene to the dynamic scene through the transition scene, setting the refresh frequency of the display unit as a sum of the frame composition frequency and a second preset value, when the sum of the frame composition frequency and a first preset value is greater than or equal to a preset minimum refresh frequency, wherein the first preset value is smaller than the second preset value. ### Claim 9 A device is provided, comprising: a processor; a memory; and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the processor, the one or more programs including: a real-time frame composition frequency acquiring module, configured to acquire a frame composition frequency of image frames, wherein each of the image frames is composed from images rendered by various applications; a refresh frequency determining module, configured to determine a refresh frequency of the display unit based on the frame composition frequency, when the frame composition frequency is less than a preset maximum refresh frequency; and a display unit refreshing module, configured to refresh a screen of the display unit at the determined refresh frequency; wherein the real-time frame composition frequency acquiring module is further configured to: acquire time taken by the processor to complete composition of each of N successive image frames displayed immediately before performing the acquiring operation; and determine the frame composition frequency of the image frames according to the following formula: S = 1 / ∑ i = 1 N ⁢ ⁢ ( T i / N ) , where S is the frame composition frequency of the image frames, and Ti is time taken by the processor to complete composition of an i-th image frame among the N successive image frames displayed immediately before performing the acquiring operation. ### Claim 10 (depends on 9) The device of claim 9, wherein the refresh frequency determining module is further configured to refresh the screen of the display unit at the preset maximum refresh frequency, when the frame composition frequency is no less than the preset maximum refresh frequency. ### Claim 11 (depends on 9) The device of claim 9, wherein the refresh frequency determining module is further configured to determine the refresh frequency of the display unit based on a relationship between the frame composition frequency and a preset minimum refresh frequency and a relationship between the frame composition frequency and a preset maximum refresh frequency, when a sum of the frame composition frequency and a first preset value is less than the preset maximum refresh frequency. ### Claim 12 (depends on 11) The device of claim 11, wherein the refresh frequency determining module is further configured to: set the refresh frequency of the display unit as a sum of the frame composition frequency and a second preset value, when the sum of the frame composition frequency and the first preset value is greater than and or equal to the preset minimum refresh frequency, wherein the sum of the frame composition frequency and the second preset value is less than the preset maximum refresh frequency; and set the refresh frequency of the display unit as the preset minimum refresh frequency, when the sum of the frame composition frequency and the first preset value is less than the preset minimum refresh frequency. ### Claim 13 (depends on 12) The device of claim 12, wherein the first preset value is set as 0, and the second preset value is set as 2. ### Claim 14 A non-transitory computer-readable storage medium for storing computer executable instructions, the computer executable instructions being used to control a processor to execute a method for control of a refresh frequency of a display unit, the display unit being in communication with the processor and configured to display image frames processed by the processor on a screen of the display unit, the method comprising: acquiring a frame composition frequency of image frames, wherein each of the image frames is composed from images rendered by various applications; determining a refresh frequency of the display unit based on the frame composition frequency, when the the frame composition frequency is less than a preset maximum refresh frequency; and refreshing a screen of the display unit at the determined refresh frequency wherein acquiring the frame composition frequency of image frames comprises: acquiring time taken by the processor to complete composition of each of N successive image frames displayed immediately before performing the acquiring operation; and determining the frame composition frequency of the image frames according to the following formula: S = 1 / ∑ i = 1 N ⁢ ⁢ ( T i / N ) , where S is the frame composition frequency of the image frames, and Ti is time taken by the processor to complete composition of an i-th image frame among the N successive image frames displayed immediately before performing the acquiring operation. ### Claim 15 (depends on 14) The non-transitory computer-readable storage medium of claim 14, wherein the method further comprises: refreshing the screen of the display unit at the preset maximum refresh frequency, when the frame composition frequency is no less than the preset maximum refresh frequency. ### Claim 16 (depends on 14) The non-transitory computer-readable storage medium of claim 14, wherein determining the refresh frequency of the display unit based on the frame composition frequency comprises: determining the refresh frequency of the display unit based on a relationship between the frame composition frequency and a preset minimum refresh frequency and a relationship between the frame composition frequency and the preset maximum refresh frequency, when a sum of the frame composition frequency and a first preset value is less than the preset maximum refresh frequency. ### Claim 17 (depends on 16) The non-transitory computer-readable storage medium of claim 16, wherein determining the refresh frequency of the display unit based on the relationship between the frame composition frequency and the preset minimum refresh frequency and the relationship between the frame composition frequency and the preset maximum refresh frequency comprises: setting the refresh frequency of the display unit as a sum of the frame composition frequency and a second preset value, when the sum of the frame composition frequency and the first preset value is greater than and or equal to the preset minimum refresh frequency, wherein the sum of the frame composition frequency and the second preset value is less than the preset maximum refresh frequency; and setting the refresh frequency of the display unit as the preset minimum refresh frequency, when the sum of the frame composition frequency and the first preset value is less than the preset minimum refresh frequency.