Privacy media signal control system based on mobile phone key switching

Abstract

The present application relates to the technical field of mobile terminal privacy protection, in particular to a private media signal control system based on mobile phone key switching, which comprises an input recognition module, a rhythm judgment module, a graph construction module, an instruction analysis module and a signal switching module. In the present application, the direction change and trigger interval of the mobile phone key level state are finely combined to construct a key behavior sequence with timing characteristics. The time interval stability is combined with the trigger rhythm change state to arrange the directionality and rhythm information of the key operation into a graph structure with sequence number and trajectory direction. With the node number and arrangement order associated function instruction characteristics, the user's intention is accurately analyzed and the function instruction is implicitly generated. Through the instruction state mapping to the media signal channel, the dynamic control and switching of the audio and video collection path are completed, effectively improving the concealment, response flexibility and execution autonomy of the privacy control behavior.

Description

Technical Field

[0001] This invention relates to the field of mobile terminal privacy protection technology, and in particular to a privacy media signal control system based on mobile phone key switching. Background Technology

[0002] The field of mobile terminal privacy protection technology involves technical means to identify, control, and protect user privacy information in mobile communication devices. Core aspects include application permission management, data access behavior monitoring, privacy information desensitization, and the identification and interception of suspicious behavior. This includes protection mechanisms for sensitive content such as user personal images, voice, and location data, forming a comprehensive systemic privacy protection framework at multiple levels: operating system, application, and communication link. Traditional privacy media signal control systems refer to mechanisms for managing permissions on media signals such as image capture signals, audio capture signals, and screen recording signals in mobile terminals. The technical issue addressed is controlling the risk of user privacy leakage at the media signal level. Traditional methods achieve this control task through static permission restrictions on camera access, foreground status detection for microphone access, or prompting and blocking screen recording through operating system notification mechanisms.

[0003] Existing technologies mainly rely on the operating system's permission system for static restrictions or foreground state monitoring. These technologies are prone to failure when user interaction paths are restricted or the application environment is invisible. In particular, it is difficult to intercept microphone and camera calls in real time when the screen is off or in the background, resulting in a passive and delayed problem in privacy protection. At the same time, the prompting notification mechanism cannot deal with spoofed calls or system-level bypass operations, which means that user privacy content is at risk of being silently obtained in certain scenarios. If malicious applications continuously call the microphone in the background to listen, the lack of a dynamic discrimination mechanism will make it impossible to respond and block it in time. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing technologies and propose a privacy media signal control system based on mobile phone key switching.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a privacy media signal control system based on mobile phone keypad switching includes:

[0006] The input recognition module acquires the input level signal changes caused by the mobile phone key press, calls the rising edge and falling edge state switching recorder in the input monitoring circuit to mark the level state direction, detects the trigger time corresponding to the marked time point, and generates a key trigger behavior sequence.

[0007] The rhythm judgment module extracts multiple consecutive time intervals based on the key trigger behavior sequence, compares any three time intervals sequentially, and if the difference between two intervals is within the rhythm fluctuation limit, it is marked as a stable rhythm group and a rhythm trigger segment status identifier is generated.

[0008] Based on the rhythm trigger segment status identifier, the graph construction module calls the trigger direction and interval order in the original key trigger behavior sequence, arranges the trigger direction value and the corresponding time interval in order, assigns sequence number to the node and marks the operation trajectory direction, and generates the operation trajectory graph structure.

[0009] The instruction parsing module extracts the node sequence length and time interval span based on the operation trajectory graph structure, matches the node sequence to the set function instruction set, and performs the matching action through the correspondence between the number of nodes, the arrangement order and the level direction to generate a privacy control function identifier.

[0010] As a further embodiment of the present invention, the key triggering behavior sequence includes a trigger interval value, a trigger direction mark, and a trigger sequence number; the rhythm triggering segment status identifier includes a rhythm cycle length, a rhythm stability level, and a rhythm fluctuation range; the operation trajectory graph structure includes a node sequence number, an operation direction identifier, and a trigger time distribution; and the privacy control function identifier includes a function instruction number, a function type classification, and control trigger conditions.

[0011] As a further aspect of the present invention, the input recognition module includes:

[0012] The level change detection submodule acquires the input level signal change caused by the mobile phone key, calls the continuous level signal sample in the input monitoring circuit, detects the jump position in the signal curve by scanning point by point, extracts the edge time of the change, determines the rising edge or falling edge attribute, and obtains the edge switching time information.

[0013] The level direction labeling submodule compares the amplitude difference of adjacent level changes with the direction conversion reference value based on the edge switching time information, identifies the real-time changing directional state, assigns the identified directional attribute to the time node, and obtains the level direction labeling sequence.

[0014] The trigger behavior submodule records the time interval between adjacent trigger events based on the level direction mark sequence, extracts the time difference and direction pair between consecutive trigger pairs, calculates the time direction rhythm trend value, and obtains the key trigger behavior sequence.

[0015] As a further aspect of the present invention, the rhythm determination module includes:

[0016] The trigger interval recording submodule performs a difference calculation on the timestamps of two adjacent key triggers based on the key trigger behavior sequence, calls the time difference in the continuous time interval sequence, removes the time periods with trigger anomalies in the interval sequence, and numbers and organizes the remaining time periods according to the trigger order to generate a trigger interval sequence.

[0017] The rhythm fluctuation calculation submodule uses the trigger time interval sequence to extract any three consecutive numbered time interval data, compares the difference between the two sets of time intervals, records the change range between the differences, and determines whether the three intervals meet the condition that the change range of the difference is within the limit based on the preset rhythm fluctuation limit threshold. It then marks the data group that meets the condition and generates a stable rhythm time group identifier set.

[0018] The rhythm segment recognition submodule performs continuity detection on the rhythm time group sequence based on the stable rhythm time group identifier set, obtains the time interval that satisfies the continuous arrangement of time groups, counts the number of stable rhythm time groups within the continuous interval, and generates a rhythm trigger segment status identifier.

[0019] As a further aspect of the present invention, the map construction module includes:

[0020] The rhythm trigger parsing submodule identifies state points within a time period based on the rhythm trigger segment state identifier, compares changes in adjacent identifiers, obtains trigger timing boundary points between rhythm segments, arranges the trigger boundary points in sequence, and establishes a rhythm segment trigger boundary sequence.

[0021] The trigger sequence mapping submodule calls the rhythm segment trigger boundary sequence, extracts the direction value and time interval within the corresponding time period, establishes a direction interval pair sequence, and performs ordered mapping in combination with the rhythm segment number to generate a temporal direction interval mapping result.

[0022] The trajectory graph submodule, based on the temporal direction interval mapping result, sequentially numbers the nodes corresponding to the trigger direction according to the operation sequence, constructs the directional connection relationship between nodes, calculates the trajectory intensity index value of the nodes, and marks the connection path direction according to the numbering order based on the trajectory intensity index value and the node connection sequence to obtain the operation trajectory graph structure.

[0023] As a further aspect of the present invention, the instruction parsing module includes:

[0024] The trajectory node extraction submodule reads node trajectory information based on the operation trajectory map structure, obtains the arrangement order of node sequence in operation path through index traversal, counts the number of node sequence as node sequence length, obtains the timestamps corresponding to the start and end nodes, records the time interval span corresponding to the node sequence, and generates trajectory sequence structure parameter group.

[0025] The node sequence matching submodule calls the trajectory sequence structure parameter group, selects three indicators in sequence: node sequence length, time interval span and arrangement order, and combines them with the level direction information between nodes. It compares the number of nodes, node order and level direction matching information defined by the preset instructions, and performs item-by-item comparison operation by using the sequence consistency check and the direction logic consistency judgment method. It then filters out the functional instruction items that meet all matching conditions and generates a matching functional instruction identifier set.

[0026] The function identifier pointing submodule performs reverse indexing on the function type associated with the instruction identifier based on the matching function instruction identifier set, establishes a mapping relationship between instruction identifier and function item, selects the function identifier item associated with the real-time trajectory sequence, and generates a privacy control function identifier.

[0027] As a further aspect of the present invention, the system also includes a signal switching module:

[0028] The signal switching module uses the privacy control function identifier to call the preset control signal routing table, identify the corresponding media signal control channel type. If it is a camera control identifier, it points to the power path of video acquisition; if it is a microphone control identifier, it points to the audio acquisition path. It issues a state flip instruction to the audio acquisition path and generates a media channel control state table.

[0029] The media channel control status table includes control channel type, channel status flag, and control command identifier.

[0030] As a further aspect of the present invention, the signal switching module includes:

[0031] The control channel identification submodule calls the privacy control function identifier, reads the media signal control channel information corresponding to the function identifier in the preset control signal routing table, and classifies the identifier into camera control identifier and microphone control identifier. Based on the category of the identifier, the control channel type is identified. If it is a camera control identifier, the corresponding video acquisition power path entry in the routing table is located. If it is a microphone control identifier, the corresponding audio acquisition path entry is located, and a control channel type mapping result is generated.

[0032] The media channel switching submodule determines whether the control channel is an audio acquisition channel based on the control channel type mapping result. If it is an audio channel, it sends a state inversion command to the control interface to invert the real-time on / off state of the channel, completes the channel on / off state update, records the correspondence between the real-time state and the channel type, and generates a media channel control state table.

[0033] As a further aspect of the present invention, the operation of sending a state flip instruction to the control interface includes: after determining that the control channel is an audio acquisition channel, based on the real-time on / off state information of the audio acquisition channel item recorded in the control channel type mapping result, calling the state flip control logic, and generating a control signal instruction to close the audio acquisition channel when the real-time on / off state information is in the on state.

[0034] When the real-time on / off status information is in the off state, a control signal command to open the audio acquisition channel is generated;

[0035] The process of recording the correspondence between real-time status and channel category includes: establishing a mapping relationship between the real-time status information of the audio acquisition channel after the control signal command is executed and the channel category indicated in the audio acquisition channel item, and storing it in the media channel control status table.

[0036] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0037] In this invention, a sequence of key actions with temporal characteristics is constructed by finely combining the directional changes and trigger intervals of the key level states on a mobile phone. The trigger rhythm changes are identified by combining the stability of the time interval. The directional and rhythmic information of key operations is arranged into a graph structure with sequence numbers and trajectory directions. By associating the number of nodes and their arrangement with the features of functional instructions, the invention achieves accurate parsing of user intent and implicit generation of functional instructions without relying on operation permission mechanisms. By mapping the instruction state to the media signal channel, the invention completes the dynamic control and switching of audio and video acquisition paths, effectively improving the concealment, response flexibility, and execution autonomy of privacy control behavior. Attached Figure Description

[0038] Figure 1 This is a system flowchart of the present invention;

[0039] Figure 2 This is a flowchart of the input recognition module in this invention;

[0040] Figure 3 This is a flowchart of the rhythm judgment module in this invention;

[0041] Figure 4 This is a flowchart of the map construction module in this invention;

[0042] Figure 5 This is a flowchart of the instruction parsing module in this invention;

[0043] Figure 6 This is a flowchart of the signal switching module in this invention. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0045] In the description of this invention, it should be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, in the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0046] Please see Figure 1 The privacy media signal control system based on mobile phone keypad switching includes:

[0047] The input recognition module acquires the input level signal changes caused by the mobile phone key press, calls the rising edge and falling edge state switching recorder in the input monitoring circuit to mark the level state direction, detects the trigger time corresponding to the marked time point, records the time interval information between triggers, and combines the time interval value and level direction information according to the alignment method to generate a key trigger behavior sequence.

[0048] The rhythm judgment module extracts multiple consecutive time intervals based on the key trigger behavior sequence, compares any three time intervals in sequence, and marks them as stable rhythm groups if the difference between two segments is within the rhythm fluctuation limit. It then determines whether there is a continuous trigger cycle composed of stable rhythm groups. If so, it constitutes a definite rhythm segment and generates a rhythm trigger segment status identifier.

[0049] The graph construction module, based on the rhythm trigger segment state identifier, calls the trigger direction and interval order in the original key trigger behavior sequence, arranges the trigger direction value and the corresponding time interval in order, constructs a set of node graphs arranged in the operation order, assigns sequence numbers to the nodes and marks the operation trajectory direction, and generates the operation trajectory graph structure.

[0050] The instruction parsing module extracts the node sequence length and time interval span based on the operation trajectory graph structure, matches the node sequence to the set function instruction set, performs the matching action through the correspondence between the number of nodes, the order of arrangement and the level direction, points to the corresponding function identifier, and generates a privacy control function identifier;

[0051] The signal switching module uses the privacy control function identifier to call the preset control signal routing table, identify the corresponding media signal control channel type. If it is a camera control identifier, it points to the power path of video acquisition; if it is a microphone control identifier, it points to the audio acquisition path. It issues a state flip command to the audio acquisition path and generates a media channel control state table.

[0052] The key trigger behavior sequence includes trigger interval value, trigger direction mark, and trigger sequence number; the rhythm trigger segment status identifier includes rhythm cycle length, rhythm stability level, and rhythm fluctuation range; the operation trajectory graph structure includes node sequence number, operation direction mark, and trigger time distribution; the privacy control function identifier includes function instruction number, function type classification, and control trigger condition; and the media channel control status table includes control channel type, channel status mark, and control command identifier.

[0053] Please see Figure 2 The input recognition module includes:

[0054] The level change detection submodule acquires the input level signal change caused by the mobile phone key, calls the continuous level signal sample in the input monitoring circuit, detects the jump position in the signal curve by scanning point by point, extracts the edge time of the change, determines the rising edge or falling edge attribute, and obtains the edge switching time information.

[0055] Connect the physical pin level signal to the sampling channel, set the sampling interval to 1ms, and the continuous sampling period to 300ms to capture the complete user key press cycle. Within this period, continuously collect raw level data and form a timing level sequence. Extract the instantaneous voltage value at each sampling point and convert it to a logic level state. Values ​​below 0.5V are defined as low level, and values ​​above 2.5V are defined as high level. After obtaining the complete logic level sequence, analyze the abrupt changes in the level using a sliding window method. If there is a logical difference between the current level and the previous level, i.e., a transition from low to high or high to low, record the current moment as the level transition time point. Then, trace back 5ms to... The sequence of level fluctuations within the last 5ms interval is used to determine whether the transition is a rising edge or a falling edge. The difference in logic level state before and after the transition is used as the basis for judgment. In the actual sampling process, if the level state switches from 0 to 1 at sampling point t=123ms, it is recorded as a rising edge; if it switches from 1 to 0 at t=187ms, it is recorded as a falling edge. The occurrence time of such rising and falling edges and their corresponding edge attributes are written into the buffer queue to form a set of edge switching time information streams. In actual use cases, when the user performs a long press action, an initial rising edge is generated, and a falling edge is generated after maintaining a stable high level for a period of time. This can clearly define the start and end time of a valid key event and obtain edge switching time information.

[0056] The level direction labeling submodule compares the amplitude difference of adjacent level changes with the direction conversion reference value based on the edge switching time information, identifies the real-time changing directional state, assigns the identified directional attribute to the time node, and obtains the level direction labeling sequence.

[0057] The level change process between each group of adjacent edges is used as the analysis unit. The time interval between each rising edge and the immediately following falling edge is extracted and represented as the key activation interval. The complete level state sequence in this interval is extracted for amplitude fluctuation analysis. During the amplitude extraction process, a continuous curve is formed based on the instantaneous voltage value sampled every millisecond. The level fluctuation characteristics are fitted according to the amplitude change curve, and three types of parameters are statistically analyzed: fluctuation range, change frequency, and average level value. At the same time, the amplitude information in the above activation interval is matched one-to-one with the amplitude distribution in the standard direction template, and the comparison is performed by window movement. To determine which direction template the current amplitude characteristic is closer to, the standard "left slide" direction template is characterized by a steady rise followed by a rapid fall, with the corresponding amplitude trajectory resembling a bell curve. In contrast, the standard "right slide" direction template exhibits the opposite distribution. By superimposing error analysis, the direction of minimum error matching is determined. During the error calculation process, the total error value is obtained by summing the squared differences between the amplitude sequence to be measured and the corresponding sequence of the template point-to-point. The direction of minimum error matching is used as the direction labeling result corresponding to the real-time key press. In multiple consecutive key press events, the direction attribute result identified each time is recorded to obtain the level direction labeling sequence.

[0058] The trigger behavior submodule records the time interval between adjacent trigger events based on the level direction marker sequence, extracts the time difference and direction pair between consecutive trigger pairs, and uses the following formula:

[0059] ;

[0060] Calculate the temporal rhythm trend value to obtain the key trigger behavior sequence;

[0061] in, Indicates the temporal direction and rhythmic trend value. Indicates the first The time interval between group key events, Indicates the first The difference in key direction state in a group key event. Indicates the first Group key event direction change density factor Indicates the first The rhythm stability factor of group key events. Indicates the first The directional coupling factor of group key events. Indicates the total number of event groups that triggered the event;

[0062] Formula calculation logic extension: based on the total number of event groups For the range, for the first to The group-based trigger events are iteratively calculated, and the time interval between events is extracted from each group of events. This reflects the duration between two consecutive direction changes, multiplied by the difference in direction attributes. To obtain the rhythmic span caused by the sudden change in direction, the time interval is... Multiply by the direction change density factor This yields the local rhythm intensity of the direction switching, using the current group number. With directional stability factor Multiply by then multiply to stabilize the weights Incorporating directional consistency into the overall trend, the average of the three sums is the rhythm trend value for a single group. The sum of the trend values ​​for all groups is then divided by... This yields the time-direction rhythm trend value;

[0063] The time-direction rhythm trend value measures the degree of rhythmic change in the time, direction and density of a user's continuous directional operations. The higher the value, the more dense the directional changes, the shorter the time interval and the unstable the direction. The lower the value, the more stable the action and the more uniform the rhythm. It is used to reflect whether there are characteristics such as rapid continuous sliding or abrupt directional switching in the key behavior pattern.

[0064] Meaning of parameters and calculation process:

[0065] Record the timestamp corresponding to the event triggered in each direction, and set the swipe-up event to occur in the specified direction. The subsequent decline occurred If the interval between the two is 100ms, it is marked as a continuous direction pair. The time interval sequence between the continuous direction pairs is statistically analyzed. and the difference in directional attributes To obtain the overall directional behavior fluctuation trend;

[0066] : No. The time interval between consecutive directional events in a group, in milliseconds, is usually set to [50, 500].

[0067] : No. The angular difference between the direction vectors of group events is set in a quantized form as 0, 1, 2, and 3, corresponding to the same direction, adjacent direction, opposite direction, and random direction, respectively.

[0068] : No. The group direction vector change density factor represents the number of direction switching times per unit time, and its value ranges from [0.1, 3.0].

[0069] Stability factor weights, values ​​are set as shown in Table 1;

[0070] : Directional stability factor, indicating whether the nth group of directional events is consistent with the previous group of directions; if consistent, it is set to 1, and if inconsistent, it is set to 0.

[0071] Total number of event groups; set to 5 in this example.

[0072]

[0073] As shown in Table 1, different weight values ​​γ are set for directional behavior fluctuations at different stability levels to ensure that the influence intensity of different directional behaviors can be distinguished in the calculation.

[0074] Substitute the following example parameters:

[0075] ;

[0076] ;

[0077] ;

[0078] ;

[0079] The stability factor is medium stability, corresponding to γ=1.0;

[0080] Calculate item by item according to the formula:

[0081] ;

[0082] ;

[0083] ;

[0084] ;

[0085] Substitute into the formula to calculate:

[0086] ;

[0087] The results indicate that the temporal rhythm trend value is 73.83, which can be used as a directional feature input for subsequent action recognition.

[0088] The advantage of the formula is that by introducing a weighted average of four parameters—time interval, direction difference value, density factor, and direction stability factor—it can not only express the rhythm of direction changes but also quantify the behavior pattern triggered by buttons, thereby enhancing the accuracy of direction feature recognition and providing highly consistent feature quantities for subsequent pattern recognition.

[0089] Please see Figure 3 The rhythm judgment module includes:

[0090] The trigger interval recording submodule is based on the key trigger behavior sequence. It performs difference calculation on the timestamps of two adjacent key triggers, calls the time difference in the continuous time interval sequence, removes the time periods with trigger anomalies in the interval sequence, and numbers and organizes the remaining time periods according to the trigger order to generate the trigger interval sequence.

[0091] Extract the timestamp sequence recorded for each key press from the user device. The timestamp can be the millisecond-level event time recorded in the operating system log. For example, when the user quickly clicks a key, the system records the first click as 1.003 seconds, the second click as 1.501 seconds, and the third click as 2.000 seconds. By reading the timestamps, the original time sequence can be obtained, and the time interval between adjacent timestamps can be calculated. This is then organized into an interval data sequence, forming a complete record of the trigger time interval during the operation. It is necessary to determine whether there are any abnormal items in the interval values ​​that are too large or too small. If the interval data is higher than 1.5 seconds during an operation, it can be initially identified as an abnormal item. Such anomalies are caused by system blockage or user behavior deviation and need to be removed. After removal, the remaining interval values ​​are numbered according to their order of appearance in the operation behavior sequence, forming a time interval sequence with a clear structure and uniform numbering. After the user makes six valid clicks, five sets of standard numbered time intervals are generated. The numbering order is arranged from 1 to 5 according to the order of appearance. This is completely organized into a binary sequence of number plus corresponding time difference. The structure can ensure the data integrity and sorting validity in the subsequent rhythm calculation process, generating the trigger time interval sequence.

[0092] The rhythm fluctuation calculation submodule uses a trigger time interval sequence to extract any three consecutively numbered time interval data segments in sequence, compares the difference between the two sets of time intervals, records the change range between the differences, and determines whether the three interval segments meet the condition that the change range of the difference is within the limit based on the preset rhythm fluctuation limit threshold. It then marks the data groups that meet the conditions and generates a stable rhythm time group identifier set.

[0093] The trigger time interval sequence needs to be processed using a sliding window. The time difference values ​​of any three consecutive numbered segments are extracted sequentially and compared one by one. Each comparison selects three adjacent numbered data segments, designated as segment 1, segment 2, and segment 3. The variation amplitude between the first and second segments, and between the second and third segments, is calculated separately. It is determined whether the difference is within the rhythm fluctuation limit. If the variation amplitudes are close, it is considered a stable rhythm combination. During this process, the sliding window moves one position at a time, continuously detecting three consecutive time interval combinations within the entire sequence. A fixed fluctuation range can be set to judge the results, ensuring no erroneous marking due to abrupt interval changes. When the user clicks the button at a stable frequency, with each interval remaining relatively constant at around 0.50 seconds, the data is marked as a stable group. If a segment's interval changes significantly, such as suddenly changing from 0.50 seconds to 0.95 seconds, this segment is excluded. The detection action requires consistency judgment for each group of three intervals. By recording the sequence positions that meet the rhythm standard, a stable rhythm time group identifier set is generated.

[0094] The rhythm segment recognition submodule performs continuity detection on the rhythm time group sequence based on the stable rhythm time group identifier set, obtains the time interval that satisfies the continuous arrangement of time groups, counts the number of stable rhythm time groups within the continuous interval, and generates a rhythm trigger segment status identifier.

[0095] The continuity of the identifiers needs to be logically determined, that is, whether each stable rhythm time group is arranged continuously in the order of numbering. During the operation, the numbers in the stable group identifier set are compared one by one to determine whether adjacent numbers are continuously increasing. If the continuity is established, they will be classified into a continuous rhythm interval. At the same time, the number of stable groups in each continuous rhythm interval needs to be summarized, and intervals that meet the quantity requirements are filtered. It is set that a continuous rhythm segment must contain at least three stable time groups. If a group with numbers 4, 5, 6, and 7 is found during the detection, it can be determined that this group meets the condition. If another group is 9 and 10, which only contains two groups, it is rejected and does not participate in the identifier generation. The rhythm group intervals that meet the conditions will be mapped back to the original time range. The trigger times corresponding to numbers 4 to 7 are set to 2.002 seconds to 4.000 seconds, respectively. Then the interval time is identified as a valid rhythm segment, and complete status information is established. Using the number, interval time, and number of groups as the labeling basis, a rhythm trigger segment status identifier is generated according to the rhythm time intervals that meet the conditions.

[0096] Please see Figure 4 The map construction module includes:

[0097] The rhythm trigger parsing submodule identifies state points within a time period based on the rhythm trigger segment status identifier, compares changes in adjacent identifiers, obtains trigger timing boundary points between rhythm segments, arranges the trigger boundary points in sequence, and establishes a rhythm segment trigger boundary sequence.

[0098] The system receives a sequence of labeled rhythmic states, derived from raw motion data collected in real time by the device. A time-continuous dataset is formed through fixed-period sampling. The sequence is traversed to identify state change events. By comparing the trend of state label changes at adjacent times, it determines whether a significant boundary has emerged between a stable state and a triggered state. The process involves dividing the time axis into multiple non-overlapping segments and constructing a state judgment window within each segment. The system continuously monitors the changes in state signals over specific time periods, filtering for stable transition points. During the detection of rhythmic actions such as clapping and stepping, the system analyzes the surge trend and fluctuation direction of the signal to extract critical frames from stillness to action frame by frame, determining whether they are valid trigger points. If identified, the timestamp and number corresponding to the critical frame are included in the trigger candidate set, and boundary confirmation processing continues for subsequent frames. For each trigger point, it is also necessary to determine whether a stable downward trend in the state occurs in the subsequent time. If the boundary characteristics are met, a rhythmic segment trigger boundary sequence is established, with the current point as the starting point of the rhythmic segment and subsequent stable points as the ending points.

[0099] The trigger sequence mapping submodule calls the rhythm segment trigger boundary sequence, extracts the direction value and time interval within the corresponding time period, establishes a direction interval pair sequence, and performs ordered mapping in combination with the rhythm segment number to generate the temporal direction interval mapping result;

[0100] The time periods corresponding to the boundaries are mapped one-to-one with the operation direction values. The start and end points of the rhythm segments are indexed on the time axis. Within the time interval of each rhythm segment, the original direction data is sampled at fixed time intervals, and a mapping relationship between the time series and the direction values ​​is established. The sampling process is executed according to the strategy of uniform distribution within the rhythm segment to ensure that the direction feature sampling points of different rhythm segments are consistent, which is conducive to subsequent comparison. Differential processing is performed on each group of direction value sequences. By comparing the change trend between two adjacent direction values ​​frame by frame, the discrete sequence of direction change is calculated to characterize the direction fluctuation within the rhythm segment. The processing method can effectively reveal the continuity and abrupt change characteristics of direction change. It is suitable for identifying action segments with significant direction changes in various operation types. When analyzing the direction sequence of a fast arm swing action, several frames with steep increases or decreases in direction angle can be observed in the sequence. The change points will be clearly recorded and mapped to the number of the current rhythm segment to generate the time sequence direction interval mapping result.

[0101] The trajectory mapping submodule, based on the temporal directional interval mapping results, sequentially numbers the nodes corresponding to the trigger directions according to the operation sequence, constructing directional connection relationships between nodes using the formula:

[0102] ;

[0103] Calculate the trajectory intensity index value of the node, and based on the trajectory intensity index value and the node connection order, mark the connection path direction according to the number order to obtain the operation trajectory map structure;

[0104] in, Indicates the first The trajectory intensity index value of each node, Indicates the first The trigger direction value of each node. Indicates the first The time interval between each node and the previous node Indicates the first The trigger direction value of each node. Indicates the first The time interval between each node and the previous node This represents the total number of nodes in the graph;

[0105] The calculation logic of the formula is as follows: By multiplying the direction value of the current node by the time interval, subtracting the average of the sum of the products of the direction values ​​and time intervals of the nodes, and taking the square root of the difference, the degree of difference between the node and the overall trajectory is obtained. The product of the direction and interval of the current node is calculated, which represents the contribution intensity of the node in the time-direction space. The products of the direction and interval of all nodes in the map are accumulated and averaged according to the total number of nodes, which represents the characteristics of the overall trajectory. The current node value is subtracted from this average value, and the difference is square rooted to output a quantifiable intensity value with directional deviation significance. The larger the value, the more obvious the deviation of the node from the average trend of the overall trajectory, which can be used for the selection of key nodes in the trajectory.

[0106] The trajectory intensity index value of a node indicates the degree of relative deviation of the node in terms of directional and temporal coupling. The larger the index value, the more prominent the directional change of the node in the trajectory, which can be used to determine whether the node is a key position or turning point in the path.

[0107] Meaning of parameters and calculation process:

[0108] : indicates the first in the atlas The trajectory intensity index of each node; the larger the value, the greater the deviation of the node's directional change from the overall trajectory.

[0109] : for the first The trigger direction value of each node, in degrees, represents the direction information measured by the direction sensor at any given moment.

[0110] : for the first The time interval between each node and the previous node, in seconds (s), is obtained by recording the difference in node timestamps.

[0111] : is the first in the atlas The trigger direction value of each node, and Same meaning;

[0112] : for the first The time interval between each node and the previous node;

[0113] : This represents the total number of nodes in the graph, and its value is a positive integer, representing the total number of nodes involved in the calculation;

[0114] The parameter acquisition process is explained below:

[0115] Direction value The direction information is collected from the inertial sensor, with a sampling frequency of 100Hz. Five frames of data are taken from the trigger time of each node and their average value is used as the current direction value.

[0116] Time interval It is obtained by subtracting the previous node's timestamp from the current node's timestamp;

[0117] Number of nodes The total number of nodes formed after the graph is constructed;

[0118] All parameters are numerical data, obtained directly through sensor sampling and timestamp calculation, without the need for quantization conversion;

[0119] The actual trajectory map is now set to contain 5 nodes, with the following direction values ​​and time intervals:

[0120]

[0121] As shown in Table 2, the direction value and time interval are obtained from sensor data records and after interpolation correction.

[0122] The formula calculation process is as follows:

[0123] calculate ;

[0124] Calculate nodal products:

[0125] ;

[0126] ;

[0127] ;

[0128] ;

[0129] Summation: ;

[0130] Calculate the average: ;

[0131] Difference: ;

[0132] Prescription: ;

[0133] Substitute into the formula to calculate:

[0134] ;

[0135] The results show that the trajectory intensity index is 0.861. If the trajectory intensity benchmark value is set to 0.5 (the benchmark value is set based on the 75th percentile of the mean of the standard deviation of the rate of change of the direction of the spectrum, and the statistical analysis results are between [0.35, 0.65]), then the trajectory intensity of the current node is higher than the benchmark. This indicates that the direction-time coupling feature of node 5 has stronger discriminative power and can be preferentially used for path derivation or feature label generation.

[0136] The advantage of the formula is that by introducing a comparison of the product of direction value and time interval, it can measure the direction-time coupling offset of each node in the overall trajectory feature, avoid the one-sidedness of traditional path analysis that only considers a single direction or distance, significantly improve the robustness of node importance assessment and the accuracy of temporal matching, and enhance the identification ability of trajectory map and the quality of path construction in the whole.

[0137] Please see Figure 5 The instruction parsing module includes:

[0138] The trajectory node extraction submodule is based on the operation trajectory graph structure. It reads the node trajectory information, obtains the arrangement order of the node sequence in the operation path through index traversal, counts the number of node sequences as the node sequence length, obtains the timestamps corresponding to the start and end nodes, records the time interval span corresponding to the node sequence, and generates a trajectory sequence structure parameter group.

[0139] The system needs to extract user interaction behavior node information recorded in the graph. The node data comes from touch trajectories, sliding paths, or mouse click events on the terminal device interface. The system records the position and associated information of each node in structured data according to time sequence, setting node number, node coordinates, trigger time, etc. By indexing and traversing the graph structure, the actual arrangement order of nodes in the operation path is identified. A trajectory line can be represented as node A→B→C→D. The system reads the record entries of each node in sequence, sorts the node sequence according to the recording time, extracts and counts the total number of nodes to obtain the node sequence length. If the operation trajectory contains four nodes, the length is recorded as 4. At the same time, the timestamp information of the start node and the end node in the sequence is extracted and identified as the start and end time points of the path, respectively. The start time is set to 10:02:15.300 and the end time is set to 10:02:17.800. The time difference between the two is the time interval span of the trajectory sequence. The calculation results are integrated with the aforementioned number of nodes and node order to generate a trajectory sequence structure parameter group.

[0140] The node sequence matching submodule calls the trajectory sequence structure parameter group, selects three indicators in sequence: node sequence length, time interval span, and arrangement order, and combines them with the level direction information between nodes. It compares the number of nodes, node order and level direction matching information defined by the preset instructions, and performs item-by-item comparison operation by using the sequence consistency check and the direction logic consistency judgment method. It then filters out the functional instruction items that meet all matching conditions and generates a matching functional instruction identifier set.

[0141] The core parameters are extracted, including node sequence length, time interval span, and arrangement order. These parameters are then compared sequentially with the predefined functional instruction set set in the system. Each instruction set includes standardized node quantity requirements, node arrangement structure, and level direction relationship information. The matching process employs a two-stage comparison mechanism: first, a sequence consistency check is performed, comparing the node arrangement order in the current trajectory with the standard order in a certain instruction template to determine if there is a total sequence match or a partially nested structure; second, a logical consistency check of the level direction is performed, which can be represented as the relative coordinate direction relationship between nodes, such as up, down, left, right, diagonal, etc. If the direction change between nodes in the real-time trajectory is consistent with the direction change logic required by the preset instruction, it is determined that the direction is consistent. The process requires traversing the entire instruction set, comparing each functional instruction one by one, and selecting instruction items that meet the matching conditions in terms of node quantity, sequence arrangement, and direction logic. The system records the unique identifier number of the instruction and outputs it uniformly, generating a matching functional instruction identifier set.

[0142] The function identifier pointing submodule performs a reverse index on the function type associated with the instruction identifier based on the matching function instruction identifier set, establishes a mapping relationship between instruction identifier and function item, selects the function identifier item associated with the real-time trajectory sequence, and generates a privacy control function identifier.

[0143] A reverse index is used to index the function category corresponding to the instruction identifier. The reverse index relationship is established in advance through a function definition table. Each function instruction identifier in the function definition table is mapped one-to-one with the privacy control function it represents. For example, instruction ID001 corresponds to the "turn off the front camera" function, ID002 corresponds to "block voice input", etc. The function item pointed to by the matching instruction identifier is retrieved item by item by using a lookup table. The function items matched by the current real-time trajectory sequence are integrated with the privacy control level related parameters to form a state structure that can be used for control calls. The state structure uniformly marks information such as function identifier, instruction source trajectory, and privacy category to generate a privacy control function identifier.

[0144] Please see Figure 6 The signal switching module includes:

[0145] The control channel identification submodule calls the privacy control function identifier, reads the media signal control channel information corresponding to the function identifier in the preset control signal routing table, and classifies the identifier into camera control identifier and microphone control identifier. Based on the category of the identifier, the control channel type is identified. If it is a camera control identifier, the corresponding video acquisition power path entry in the routing table is located. If it is a microphone control identifier, the corresponding audio acquisition path entry is located, and a control channel type mapping result is generated.

[0146] The system performs category identification on privacy control function identifiers to determine whether the privacy function category it points to is camera-related control or microphone-related control. If the user triggers the camera shutdown operation through trajectory operation, the function identifier value will be set to "CAM-OFF". This value is used as an index to look up the preset control signal routing table. In the routing table, the system establishes a corresponding media signal control channel entry for each type of function identifier, including information such as channel type, device path, and interface number. Setting "CAM-OFF" points to the video acquisition power path, and the control path is the signal channel with GPIO interface number A12. On the other hand, "MIC-OFF" points to the PCM control line in the audio acquisition device path. During the matching process, the system needs to perform judgment branch processing according to the identifier category. If the current identifier is identified as a camera control identifier, the system locates the camera power supply path entry according to the corresponding entry in the routing table. If the identifier is identified as a microphone control identifier, the system should locate the path record bound to the audio device interface. This location process is executed based on the logical structure of one-to-one correspondence between function identifiers and channel types in the table. The system outputs the structured media signal control path information associated with the current control command, generating a control channel type mapping result.

[0147] The media channel switching submodule determines whether the control channel is an audio acquisition channel based on the control channel type mapping result. If it is an audio channel, it sends a state inversion command to the control interface to invert the real-time on / off state of the channel, completes the channel on / off state update, records the correspondence between the real-time state and the channel type, and generates a media channel control state table.

[0148] The media channel switching submodule determines whether the control channel is an audio acquisition channel based on the control channel type mapping result. If it is an audio channel, it sends a state inversion command to the control interface to invert the real-time on / off state of the channel, completes the channel on / off state update, records the correspondence between the real-time state and the channel type, and generates a media channel control state table.

[0149] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments that can be applied to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A privacy media signal control system based on mobile phone keypad switching, characterized in that, The system includes: The input recognition module acquires the input level signal changes caused by the mobile phone key press, calls the rising edge and falling edge state switching recorder in the input monitoring circuit to mark the level state direction, detects the trigger time corresponding to the marked time point, and generates a key trigger behavior sequence. The rhythm judgment module extracts multiple consecutive time intervals based on the key trigger behavior sequence, compares any three time intervals sequentially, and if the difference between two intervals is within the rhythm fluctuation limit, it is marked as a stable rhythm group and a rhythm trigger segment status identifier is generated. Based on the rhythm trigger segment state identifier, the graph construction module calls the order of the trigger direction and the time interval in the original key trigger behavior sequence, takes the combination of the trigger direction and the time interval arranged in order as a node, assigns a sequence number to the node, and marks the operation trajectory direction according to the trigger direction to generate an operation trajectory graph structure. The instruction parsing module extracts the node sequence length and time interval span based on the operation trajectory graph structure, matches the node sequence to the set function instruction set, and performs the matching action through the correspondence between the number of nodes, the arrangement order and the level direction to generate a privacy control function identifier; The signal switching module uses the privacy control function identifier to call the preset control signal routing table, identify the corresponding media signal control channel type. If it is a camera control identifier, it points to the power path of video acquisition; if it is a microphone control identifier, it points to the audio acquisition path. It issues a state flip instruction to the audio acquisition path and generates a media channel control state table. The media channel control status table includes control channel type, channel status flag, and control command identifier.

2. The privacy media signal control system based on mobile phone keypad switching according to claim 1, characterized in that, The key triggering behavior sequence includes a trigger interval value, a trigger direction marker, and a trigger sequence number. The rhythm trigger segment status identifier includes the rhythm cycle length, rhythm stability level, and rhythm fluctuation range. The operation trajectory graph structure includes a node sequence number, an operation direction identifier, and a trigger time distribution. The privacy control function identifier includes a function instruction number, a function type classification, and control trigger conditions.

3. The privacy media signal control system based on mobile phone keypad switching according to claim 1, characterized in that, The input recognition module includes: The level change detection submodule acquires the input level signal change caused by the mobile phone key, calls the continuous level signal sample in the input monitoring circuit, detects the jump position in the signal curve by scanning point by point, extracts the edge time of the change, determines the rising edge or falling edge attribute, and obtains the edge switching time information. The level direction labeling submodule compares the amplitude difference of adjacent level changes with the direction conversion reference value based on the edge switching time information, identifies the real-time changing directional state, assigns the identified directional attribute to the time node, and obtains the level direction labeling sequence. The trigger behavior submodule records the time interval between adjacent trigger events based on the level direction mark sequence, extracts the time difference and direction pair between consecutive trigger pairs, calculates the time direction rhythm trend value, and obtains the key trigger behavior sequence.

4. The privacy media signal control system based on mobile phone keypad switching according to claim 3, characterized in that, The rhythm determination module includes: The trigger interval recording submodule performs a difference calculation on the timestamps of two adjacent key triggers based on the key trigger behavior sequence, calls the time difference in the continuous time interval sequence, removes the time periods with trigger anomalies in the interval sequence, and numbers and organizes the remaining time periods according to the trigger order to generate a trigger interval sequence. The rhythm fluctuation calculation submodule uses the trigger time interval sequence to extract any three consecutively numbered time interval data, compares the difference between the two sets of time intervals, records the change range between the differences, and determines whether the three intervals meet the condition that the change range of the difference is within the limit based on the preset rhythm fluctuation limit threshold. It then marks the data group that meets the condition and generates a stable rhythm time group identifier set. The rhythm segment recognition submodule performs continuity detection on the rhythm time group sequence based on the stable rhythm time group identifier set, obtains the time interval that satisfies the continuous arrangement of time groups, counts the number of stable rhythm time groups within the continuous interval, and generates a rhythm trigger segment status identifier.

5. The privacy media signal control system based on mobile phone keypad switching according to claim 4, characterized in that, The map construction module includes: The rhythm trigger parsing submodule identifies state points within a time period based on the rhythm trigger segment state identifier, compares the changes in adjacent rhythm trigger segment state identifiers, obtains the trigger timing boundary points between rhythm segments, arranges the trigger boundary points in sequence, and establishes a rhythm segment trigger boundary sequence. The trigger sequence mapping submodule calls the rhythm segment trigger boundary sequence, extracts the direction value and time interval within the corresponding time period, establishes a direction interval pair sequence, and performs ordered mapping in combination with the rhythm segment number to generate a temporal direction interval mapping result. The trajectory graph submodule, based on the temporal direction interval mapping result, sequentially numbers the nodes corresponding to the trigger direction according to the operation sequence, constructs the directional connection relationship between nodes, calculates the trajectory intensity index value of the nodes, and marks the connection path direction according to the numbering order based on the trajectory intensity index value and the node connection sequence to obtain the operation trajectory graph structure.

6. The privacy media signal control system based on mobile phone keypad switching according to claim 5, characterized in that, The instruction parsing module includes: The trajectory node extraction submodule reads node trajectory information based on the operation trajectory map structure, obtains the arrangement order of node sequence in operation path through index traversal, counts the number of node sequence as node sequence length, obtains the timestamps corresponding to the start and end nodes, records the time interval span corresponding to the node sequence, and generates trajectory sequence structure parameter group. The node sequence matching submodule calls the trajectory sequence structure parameter group, selects three indicators in sequence: node sequence length, time interval span and arrangement order, and combines them with the level direction information between nodes. It compares the number of nodes, node order and level direction matching information defined by the preset instructions, and performs item-by-item comparison operation by using the order consistency check and the direction logic consistency judgment method. It then filters out the functional instruction items that meet all matching conditions and generates a matching functional instruction identifier set. The function identifier pointing submodule performs reverse indexing on the function type associated with the instruction identifier based on the matching function instruction identifier set, establishes a mapping relationship between instruction identifier and function item, selects the function identifier item associated with the real-time trajectory sequence, and generates a privacy control function identifier.

7. The privacy media signal control system based on mobile phone keypad switching according to claim 1, characterized in that, The signal switching module includes: The control channel identification submodule calls the privacy control function identifier, reads the media signal control channel information corresponding to the function identifier in the preset control signal routing table, and classifies the identifier into camera control identifier and microphone control identifier. Based on the category of the identifier, the control channel type is identified. If it is a camera control identifier, the corresponding video acquisition power path entry in the routing table is located. If it is a microphone control identifier, the corresponding audio acquisition path entry is located, and a control channel type mapping result is generated. The media channel switching submodule determines whether the control channel is an audio acquisition channel based on the control channel type mapping result. If it is an audio channel, it sends a state inversion command to the control interface to invert the real-time on / off state of the channel, completes the channel on / off state update, records the correspondence between the real-time state and the channel type, and generates a media channel control state table.

8. The privacy media signal control system based on mobile phone keypad switching according to claim 7, characterized in that, The operation of sending a state flip instruction to the control interface includes: after determining that the control channel is an audio acquisition channel, based on the real-time on / off state information of the audio acquisition channel item recorded in the control channel type mapping result, calling the state flip control logic, and generating a control signal instruction to close the audio acquisition channel when the real-time on / off state information is in the on state. When the real-time on / off status information is in the off state, a control signal command to open the audio acquisition channel is generated; The process of recording the correspondence between real-time status and channel category includes: establishing a mapping relationship between the real-time status information of the audio acquisition channel after the control signal command is executed and the channel category indicated in the audio acquisition channel item, and storing it in the media channel control status table.

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