Multimedia variable-speed playing control method and device based on physical knob and medium

Abstract

The invention discloses a multimedia variable-speed playing control method and device based on a physical knob, and a medium. The method comprises the following steps: carrying out de-jitter processing on a rotation frequency signal of a variable-speed playing knob acquired in real time by using a sliding window mean filter; in response to the cruise variable-speed playing mode request, mapping the rotation frequency into a first media playing speed in real time by adopting an angle step mapping mode, and playing based on the first media playing speed; and in response to the common variable-speed playing mode request, mapping the rotation frequency into a second media playing speed in real time by adopting a dynamic threshold mapping mode, and playing based on the second media playing speed. According to the method and the device, under the cooperation of dual modes of cruise variable-speed playing and common variable-speed playing, frame-by-frame retrieval is realized, a certain accurate frame of picture is quickly positioned, meanwhile, the anti-interference capability is improved, the identification error rate is reduced, the media playing speed jump is reduced, and the working efficiency of slow playing production personnel is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of multimedia playback control, and particularly to a multimedia variable-speed playback control method, device, and computer-readable medium based on a physical knob, which can be applied to variable-speed playback control on multimedia playback platform ends such as live broadcasts. Background Art

[0002] On multimedia playback platform ends such as live broadcasts, slow-motion production personnel need to use a knob to variably browse the content of the playback to locate a precise frame of the picture, so as to edit out wonderful clips for presentation to the audience. This knob is a physical knob on the playback console, and the following defects are found in actual use:

[0003] First, directly controlling the playback speed using a mechanical structure has limited playback accuracy and it is difficult to achieve frame-by-frame retrieval.

[0004] Second, due to the physical jitter of the variable-speed playback knob, the playback speed is prone to jump.

[0005] The above defects reduce the work efficiency of slow-motion production personnel. Summary of the Invention

[0006] Aiming at the above defects, the technical problem to be solved by the present invention is to provide a multimedia variable-speed playback control method, device, and medium based on a physical knob to solve the problems of limited playback accuracy and easy jump of the playback speed in the prior art, thereby reducing the work efficiency of slow-motion production personnel.

[0007] To this end, a first aspect of the embodiments of the present application provides a multimedia variable-speed playback control method based on a physical knob, including the following steps:

[0008] Debounce the rotation frequency signal of the variable-speed playback knob collected in real time using a sliding window mean filter;

[0009] In response to a cruise variable-speed playback mode request, map the filtered rotation frequency to the first media playback speed in real time using an angle binning mapping method, and play the current media content based on the first media playback speed;

[0010] In response to a normal variable-speed playback mode request, map the filtered rotation frequency to the second media playback speed in real time using a dynamic threshold mapping method, and play the current media content based on the second media playback speed.

[0011] Based on the above technical solution, under the coordination of the cruise variable-speed playback and the ordinary variable-speed playback dual modes, the speed deviation control within the variable-speed range of 0.01x - 32x is achieved, which can meet the requirements of frame-by-frame retrieval, quickly locate to a precise frame of the picture. At the same time, the anti-interference ability of the rotation frequency signal is improved, the error rate of rotation frequency recognition is reduced, the jump of the media playback speed is reduced, and the work efficiency of slow-play production personnel is improved.

[0012] In the above method, preferably, the rotation frequency after filtering is mapped to the second media playback speed in a dynamic threshold mapping manner, which specifically includes the following steps:

[0013] Set the upper limits of the low-multiple playback control area, the middle-multiple playback control area, and the high-multiple playback control area of the rotation frequency respectively;

[0014] Use a three-segment non-linear mapping function to map the filtered rotation frequency value to the second media playback speed; among them, the low-multiple playback control area uses an S-shaped curve speed mapping function, the middle-multiple playback control area uses a logarithmic curve speed mapping function, and the high-multiple playback control area uses an asymptotic saturation curve speed mapping function; when the filtered rotation frequency is within the low-multiple playback control area, use the S-shaped curve speed mapping function to map the filtered rotation frequency to the second media playback speed in real time; when the filtered rotation frequency is within the middle-multiple playback control area, use the logarithmic curve speed mapping function to map the filtered rotation frequency to the second media playback speed in real time; when the filtered rotation frequency is within the high-multiple playback control area, use the asymptotic saturation curve speed mapping function to map the filtered rotation frequency to the second media playback speed in real time. This implementation method uses speed mapping functions with different curves for the low-multiple, middle-multiple, and high-multiple playback control areas respectively, so that the low-multiple playback can be adjusted more finely and the high-multiple playback can shift gears more smoothly.

[0015] In the above method, preferably,

[0016] The S-shaped curve speed mapping function is: y = 0.05 + 0.95×(1.0 / (1.0 + exp(-12.0×(x - 0.5))));

[0017] The logarithmic curve speed mapping function is: y = 1.0 + 5.0×pow(t, 0.7);

[0018] The asymptotic saturation curve speed mapping function is: y = 6.0 + 4.0×(1.0 - exp(-(frequency - MID_CUTOFF) / 400.0));

[0019] Where:

[0020] y represents the playback speed of the second medium;

[0021] x = frequency / LOW_CUTOFF;

[0022] t = (log(frequency) - log(LOW_CUTOFF)) / (log(MID_CUTOFF) - log(LOW_CUTOFF));

[0023] MID_CUTOFF represents the upper limit of the medium multiple playback control area, frequency represents the current rotation frequency of the variable speed playback knob, and LOW_CUTOFF represents the upper limit of the low multiple playback control area.

[0024] Through a large amount of practice, the low-speed control accuracy of these three speed mapping functions reaches ±2%, which is much higher than the traditional technology.

[0025] In the above method, preferably, the method for real-time debouncing using a sliding window mean filter is as follows:

[0026] Define a filtering window with a fixed size, and arrange the rotation frequencies of the variable speed playback knob collected in sequence to form a rotation speed sequence;

[0027] Move the filtering window to the starting position of the rotation speed sequence, and calculate the average value of the rotation frequency signals within the filtering window. Take the average value as the rotation frequency value at the starting position of the rotation speed sequence;

[0028] Move the filtering window to the next position of the rotation speed sequence, and also use the average value algorithm to calculate and obtain the rotation frequency value at the next position of the rotation speed sequence;

[0029] Repeat sliding the filtering window to calculate and obtain the rotation frequency value at each position of the rotation speed sequence.

[0030] In the above method, preferably, the following steps are further included:

[0031] Preset an acceleration threshold α and a deceleration threshold β;

[0032] Obtain the current rotation frequency of the variable speed playback knob by real-time calculation through the time stamp difference;

[0033] According to the comparison result of the rotation frequency change rate within the continuous time window with the preset acceleration threshold α and the preset deceleration threshold β, judge the rotation state of the variable speed playback knob. The rotation state includes an acceleration state and a deceleration state; when the rotation frequency change rate is greater than α, the rotation state of the variable speed playback knob is the acceleration state; when the rotation frequency change rate is less than β, the rotation state of the variable speed playback knob is the deceleration state;

[0034] In response to the acceleration state, activate the variable speed control; in response to the deceleration state, freeze the variable speed control and enable the monitoring of the playback console function buttons.

[0035] For this implementation method, the false trigger rate ≤ 1.2%.

[0036] In the above method, preferably, an angular binning mapping method is used to map the rotation frequency after filtering processing to the first media playback speed in real time, which specifically includes the following steps:

[0037] Divide the rotation angle range of the variable speed playback knob into multiple playback speed control partitions;

[0038] Preset a fixed first media playback speed for each playback speed control partition;

[0039] Obtain the rotation angle of the variable speed playback knob in real time;

[0040] Based on the playback speed control partition where the rotation angle is located, obtain the current first media playback speed, and play the current media content based on the current first media playback speed.

[0041] Using the cruise variable speed playback mode improves the convenience of variable speed operations. Combined with ordinary variable speed playback, it is easier and more convenient to control the playback accuracy.

[0042] The second aspect of the embodiments of the present application provides a multimedia variable speed playback control device based on a physical knob, including:

[0043] A debounce processing module for using a sliding window mean filter to perform debounce processing on the rotation frequency signal of the variable speed playback knob collected in real time;

[0044] A first mapping module for, in response to a cruise variable speed playback mode request, using an angular binning mapping method to map the rotation frequency after filtering processing to the first media playback speed in real time;

[0045] A second mapping module for, in response to an ordinary variable speed playback mode request, using a dynamic threshold mapping method to map the rotation frequency after filtering processing to the second media playback speed in real time;

[0046] A playback module for playing the current media content based on the second media playback speed or the first media playback speed.

[0047] In the above device, preferably, the first mapping module includes:

[0048] A low multiple playback mapping unit for, when the rotation frequency after filtering processing is within the low multiple playback control area, using an S-shaped curve speed mapping function to map the rotation frequency after filtering processing to the second media playback speed in real time;

[0049] The medium - multiple - play mapping unit is used to, when the rotation frequency after filtering is within the medium - multiple - play control area, map the rotation frequency after filtering to the second media play speed in real - time using a logarithmic - curve speed mapping function;

[0050] The high - multiple - play mapping unit is used to, when the rotation frequency after filtering is within the high - multiple - play control area, map the rotation frequency after filtering to the second media play speed in real - time using an asymptotic - saturation - curve speed mapping function.

[0051] In the above - mentioned device, preferably, it further includes:

[0052] The state - judgment module is used to judge the rotation state of the variable - speed play knob according to the comparison result between the rotation - frequency change rate within a continuous time window and a preset acceleration threshold α and a preset deceleration threshold β. The rotation state includes an acceleration state and a deceleration state. When the rotation - frequency change rate is greater than α, the rotation state of the variable - speed play knob is the acceleration state; when the rotation - frequency change rate is less than β, the rotation state of the variable - speed play knob is the deceleration state;

[0053] The execution module is used to activate the variable - speed control in response to the acceleration state, freeze the variable - speed control in response to the deceleration state, and start monitoring the function keys of the play console.

[0054] The third aspect of the embodiments of the present application provides a computer - readable medium, on which a computer program / instructions are stored, and characterized in that when the computer program / instructions are executed by a processor, the method described in any one of claims 1 to 6 is implemented.

[0055] As can be seen from the above - mentioned technical solutions, the multimedia variable - speed play control method, device, and computer - readable medium provided by the present invention solve the problems of limited play accuracy and easy speed jump in the prior art. Compared with the prior art, the present invention has the following beneficial effects:

[0056] In response to a cruise variable - speed play mode request, the rotation frequency after filtering is mapped to the first media play speed in real - time using an angle - grading mapping method, and the current media content is played based on the first media play speed; in response to a normal variable - speed play mode request, the rotation frequency after filtering is mapped to the second media play speed in real - time using a dynamic - threshold mapping method, and the current media content is played based on the second media play speed. Thus, through the cooperation of the cruise variable - speed play and the normal variable - speed play dual modes, the speed deviation control within the variable - speed range of 0.01x - 32x can be achieved, which can meet the requirements of frame - by - frame retrieval and quickly locate to a precise frame. At the same time, the anti - interference ability of the rotation - frequency signal of the variable - speed play knob is improved, the media play speed jump is reduced, and the work efficiency of slow - play production personnel is improved. Description of the Drawings

[0057] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce and explain the drawings required for the description of the embodiments of the present invention or the prior art. Obviously, the drawings in the following description are only partial embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0058] Figure 1 It is a flowchart of the multimedia variable-speed playback control method based on a physical knob in the present invention;

[0059] Figure 2 It is a flowchart of the present invention for mapping the rotation frequency after filtering processing to the first media playback speed in real time by using the angle binning mapping method;

[0060] Figure 3 It is a schematic diagram of the speed mapping function curves corresponding to the three multiple playback control areas in the present invention;

[0061] Figure 4 It is a schematic diagram of the multimedia variable-speed playback control device based on a physical knob in the present invention. Detailed Embodiments

[0062] The following will clearly and completely describe the technical solutions of the embodiments of the present invention in conjunction with the drawings of the embodiments of the present invention. Obviously, the following described embodiments are only part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0063] In order to more clearly explain and illustrate the technical solutions and implementation manners of the present invention, the following introduces several preferred specific embodiments for implementing the technical solutions of the present invention.

[0064] It should be noted that the orientation words such as "inside, outside", "front, back", and "left, right" in this article are expressed based on the product usage state as the reference object. Obviously, the use of the corresponding orientation words does not limit the protection scope of this solution.

[0065] As Figure 1 shown, a multimedia variable-speed playback control method based on a physical knob provided by the present application includes the following steps:

[0066] Step 110, using a sliding window mean filter to perform debouncing processing on the rotation frequency signal of the variable-speed playback knob collected in real time. The rotation frequency can also be referred to as the rotation speed or rotational speed.

[0067] Step 120: In response to a cruise variable-speed playback mode request, the filtered rotation frequency is mapped in real time to a first media playback speed by means of angular bin mapping, and the current media content is played based on the first media playback speed.

[0068] Step 130: In response to a normal variable-speed playback mode request, the filtered rotation frequency is mapped in real time to a second media playback speed by means of dynamic threshold mapping, and the current media content is played based on the second media playback speed.

[0069] In this application, variable-speed playback includes two playback modes: cruise variable-speed playback and normal variable-speed playback. Cruise variable-speed playback means dividing the rotation range of the variable-speed playback knob into partitions, with each partition corresponding to a fixed playback speed. When the rotation angle of the variable-speed playback knob is within the same partition, the playback speed of the current media remains unchanged and can be selected according to the user's needs. Normal variable-speed playback means that the playback speed of the current media changes in real time corresponding to the rotation frequency of the variable-speed playback knob. When making a program, slow-motion producers first use the cruise mode and select a relatively fast fixed playback speed, such as 32 times speed, to quickly browse through scenes from a long time ago (because the cruise mode plays at a fixed speed. For example, when the knob rotation is mapped to -32 times speed and then released, it will play in reverse at 32 times speed, mainly used for operators to quickly go through the playback content). When approaching the target frame, the slow-motion producer switches to the normal variable-speed playback mode through the mode switch button on the console for precise positioning within a short period. At this time, when the operator releases the knob, the playback will stop. Generally, when there is a time gap between the current time and the desired time, the operator will first quickly rotate to a high speed, slow down to a medium speed when approaching the expected time, and finally finely retrieve a certain frame through a low multiple. When released, it just locates the desired frame of the picture.

[0070] Therefore, the solution of this application can quickly locate an accurate frame through the cooperation of the two playback modes and is convenient to operate.

[0071] In the above step 110, the method of using a sliding window mean filter to perform real-time debouncing is as follows:

[0072] Define a filter window with a fixed size, and arrange the rotation frequencies of the variable-speed playback knob collected in sequence to form a rotation speed sequence;

[0073] Move the filter window to the starting position of the rotation speed sequence, and calculate the average value of the rotation frequency signals within the filter window. Take this average value as the rotation frequency value at the starting position of the rotation speed sequence;

[0074] Move the filter window to the next position of the rotation speed sequence, and also use the average value algorithm to calculate and obtain the rotation frequency value at the next position of the rotation speed sequence;

[0075] Repeat the sliding filter window to calculate the rotational frequency value at each position of the rotational speed sequence.

[0076] The filtering and debouncing process improves the anti-interference ability of the rotational frequency signal and reduces the error rate of rotational frequency identification. After the above filtering and debouncing process, the rotational frequency of the variable-speed playback knob becomes smoother to a certain extent, and correspondingly reduces the jump of the media playback speed.

[0077] In the above step 120, the rotation frequency after filtering is mapped to the first media playback speed in real time by using the angle binning mapping method, as Figure 2 shown, which specifically includes the following steps:

[0078] Step 121, divide the rotation angle range of the variable-speed playback knob into multiple playback speed control partitions.

[0079] For example, the rotation angle range of the variable-speed playback knob is [-180, +180], which is evenly divided into 8 playback speed control partitions.

[0080] Step 122, preset a fixed first media playback speed for each playback speed control partition. For example, the first media playback speeds corresponding to each playback speed control partition are [2x, 4x, 8x, 16x, 32x, 48x, 64x, 80x], where x represents the normal playback speed multiple.

[0081] Step 123, obtain the rotation angle of the variable-speed playback knob in real time.

[0082] Step 124, obtain the current first media playback speed according to the playback speed control partition where the rotation angle is located, and play the current media content based on the current first media playback speed.

[0083] In this application, through the cooperation of the ordinary variable-speed playback and the cruise variable-speed playback modes, the speed deviation control within the variable-speed range of 0.01x - 32x is achieved, meeting the requirements of frame-by-frame retrieval.

[0084] In the above step 130, the rotation frequency after filtering is mapped to the second media playback speed in real time by using the dynamic threshold mapping method, which specifically includes the following steps:

[0085] Set the upper limits (Hz) of the low multiple playback control region, the medium multiple playback control region, and the high multiple playback control region for the rotation frequency respectively. The low multiple playback control region corresponds to low multiple playback and is used to precisely control the media playback speed, such as 0.05x - 1x (x represents the multiple of the normal playback speed). The medium multiple playback control region corresponds to medium multiple playback, such as 1x - 6x. The high multiple playback control region corresponds to high multiple playback, such as 6x - 10x.

[0086] Adopt a three-segment non-linear mapping function to map the filtered rotation frequency value to the second media playback speed.

[0087] Specifically, as Figure 3 shown, the low multiple playback control region adopts an S-shaped curve speed mapping function, the medium multiple playback control region adopts a logarithmic curve speed mapping function, and the high multiple playback control region adopts an asymptotic saturation curve speed mapping function. When the filtered rotation frequency is within the low multiple playback control region, the S-shaped curve speed mapping function is used to map the filtered rotation frequency to the second media playback speed in real time; when the filtered rotation frequency is within the medium multiple playback control region, the logarithmic curve speed mapping function is used to map the filtered rotation frequency to the second media playback speed in real time; when the filtered rotation frequency is within the high multiple playback control region, the asymptotic saturation curve speed mapping function is used to map the filtered rotation frequency to the second media playback speed in real time.

[0088] For the low multiple, medium multiple, and high multiple playback control regions, speed mapping functions with different curves are adopted respectively, so that the low multiple playback can be adjusted more precisely and the high multiple playback can have a smoother gear shift.

[0089] In one embodiment:

[0090] The S-shaped curve speed mapping function is: y = 0.05 + 0.95 × (1.0 / (1.0 + exp(-12.0 × (x - 0.5)))).

[0091] The logarithmic curve speed mapping function is: y = 1.0 + 5.0 × pow(t, 0.7).

[0092] The asymptotic saturation curve speed mapping function is: y = 6.0 + 4.0 × (1.0 - exp(-(frequency - MID_CUTOFF) / 400.0)).

[0093] Where:

[0094] y represents the second media playback speed.

[0095] x = frequency / LOW_CUTOFF.

[0096] t = (log(frequency) - log(LOW_CUTOFF)) / (log(MID_CUTOFF) - log(LOW_CUTOFF)).

[0097] MID_CUTOFF represents the upper limit of the medium multiple playback control area, frequency represents the current rotation frequency of the variable speed playback knob, and LOW_CUTOFF represents the upper limit of the low multiple playback control area.

[0098] An example of the dynamic mapping between the rotation frequency of the variable speed playback knob and the second media playback speed is as follows:

[0099]

[0100] To avoid the rotation afterglow interfering with the response of other function buttons after releasing the variable speed playback knob, resulting in untimely response of subsequent editing functions, the solution of this application further includes the following steps:

[0101] Preset an acceleration threshold α and a deceleration threshold β;

[0102] Obtain the current rotation frequency of the variable speed playback knob in real time through the time stamp difference;

[0103] According to the comparison result between the rotation frequency change rate (df / dt, where f represents the rotation frequency and t represents time) within a continuous time window and the preset acceleration threshold α and deceleration threshold β, determine the rotation state of the variable speed playback knob. Among them, the rotation states include an acceleration state and a deceleration state; when the rotation frequency change rate is greater than α, the rotation state of the variable speed playback knob is the acceleration state; when the rotation frequency change rate is less than β, the rotation state of the variable speed playback knob is the deceleration state;

[0104] Respond to the acceleration state and activate the variable speed control; respond to the deceleration state, freeze the variable speed control, and enable the monitoring of the function buttons on the playback console.

[0105] Through the above processing, after releasing the variable speed playback knob, the solution of this application will automatically freeze the variable speed control function and enable the monitoring function of the function buttons on the playback console. Thereby eliminating the rotation afterglow after releasing the variable speed playback knob, being able to respond to the function buttons in a timely manner, and improving the accuracy of media playback control.

[0106] Based on the above multimedia variable speed playback control method based on a physical knob, this application also provides a multimedia variable speed playback control device based on a physical knob, as Figure 4 shown, the multimedia variable speed playback control device 100 based on a physical knob includes:

[0107] The debounce processing module 10 is used to perform debounce processing on the rotation frequency signal of the variable-speed playback knob collected in real time by using a sliding window mean filter;

[0108] The first mapping module 20 is used to respond to a cruise variable-speed playback mode request and map the filtered rotation frequency to the first media playback speed in real time by using an angle grading mapping method;

[0109] The second mapping module 30 is used to respond to a normal variable-speed playback mode request and map the filtered rotation frequency to the second media playback speed in real time by using a dynamic threshold mapping method;

[0110] The playback module 40 is used to play the current media content based on the first media playback speed or the second media playback speed.

[0111] In the above device, the second mapping module 30 includes:

[0112] The low multiple playback mapping unit 31 is used to, when the filtered rotation frequency is within the low multiple playback control area, map the filtered rotation frequency to the second media playback speed in real time by using an S-shaped curve speed mapping function;

[0113] The medium multiple playback mapping unit 32 is used to, when the filtered rotation frequency is within the medium multiple playback control area, map the filtered rotation frequency to the second media playback speed in real time by using a logarithmic curve speed mapping function;

[0114] The high multiple playback mapping unit 33 is used to, when the filtered rotation frequency is within the high multiple playback control area, map the filtered rotation frequency to the second media playback speed in real time by using an asymptotic saturation curve speed mapping function.

[0115] In the above device, it further includes:

[0116] The state judgment module 50 is used to judge the rotation state of the variable-speed playback knob according to the comparison result between the rotation frequency change rate within a continuous time window and a preset acceleration threshold α and a preset deceleration threshold β, and the rotation state includes an acceleration state and a deceleration state; when the rotation frequency change rate is greater than α, the rotation state of the variable-speed playback knob is the acceleration state, and when the rotation frequency change rate is less than β, the rotation state of the variable-speed playback knob is the deceleration state.

[0117] The execution module 60 is used to activate variable-speed control in response to the acceleration state; freeze variable-speed control in response to the deceleration state, and start monitoring function keys.

[0118] In addition, the present application also provides an electronic device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program stored in the memory, the above-mentioned multimedia variable-speed playback control method based on a physical knob is implemented.

[0119] The above-mentioned multimedia variable-speed playback control method based on a physical knob can be implemented as a computer software program. Based on this, the present invention also provides a computer-readable medium, on which a computer program is stored. When the computer program is executed by a processor, the above-mentioned live wonderful moment slow playback and playback method is implemented.

[0120] The above-mentioned multimedia variable-speed playback control method based on a physical knob can also be implemented by a computer program. Based on this, an embodiment of the present application also provides a computer program product, including a computer program / instructions. When the computer program / instructions are executed by a processor, the above-mentioned live wonderful moment slow playback and playback method is implemented.

[0121] Compared with the traditional technology, the solution of the present application has a greater improvement in terms of low-speed control accuracy and anti-jitter ability, as shown in the following table.

[0122] Index Traditional technology This application Low-speed control accuracy ±25％ ±2％ Anti-jitter ability False trigger rate ≥ 15% False trigger rate ≤ 1.2%

[0123] Based on the descriptions of the above specific embodiments, the multimedia variable-speed playback control method, device, and computer-readable medium provided by the present invention have the following advantages compared with the prior art:

[0124] First, through the cooperation of the dual modes of normal variable-speed playback and cruise variable-speed playback, the speed deviation control within the variable-speed range of 0.01x - 32x is achieved, meeting frame-by-frame retrieval, and enabling quick positioning to a precise frame of the picture, thereby improving the work efficiency of slow-play production personnel.

[0125] Second, through window mean filtering anti-shake processing, the anti-interference ability of the rotation frequency signal is improved, the error rate of rotation frequency recognition is reduced, and the jump of the media playback speed is reduced.

[0126] Third, for the low-magnification, medium-magnification, and high-magnification playback control areas, speed mapping functions with different curves are respectively adopted, enabling more fine adjustment in low-magnification playback and smoother gear shifting in high-magnification playback.

[0127] Fourth, after releasing the variable-speed playback knob, the solution of the present application will automatically freeze the variable-speed control function and activate the monitoring function of the playback console function keys. The rotational afterglow after releasing the variable-speed playback knob is eliminated, enabling timely response to function keys and improving the accuracy of media playback control.

[0128] Finally, it should also be noted that the term "including", "comprising" or any other variant thereof used in this text is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or further includes elements inherent in such a process, method, article or device. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

[0129] The present invention is not limited to the above-mentioned optimal implementation manner. Anyone should know that structural changes made under the inspiration of the present invention, as long as they have the same or similar technical solutions as the present invention, all fall within the protection scope of the present invention.

Claims

1. A multimedia variable-speed playback control method based on a physical knob, characterized in that Including the following steps: Using a sliding window mean filter to perform debouncing processing on the rotation frequency signal of the variable-speed playback knob collected in real time; In response to a cruise variable-speed playback mode request, using an angular binning mapping method to map the filtered rotation frequency to the first media playback speed in real time, and playing the current media content based on the first media playback speed; In response to a normal variable-speed playback mode request, using a dynamic threshold mapping method to map the filtered rotation frequency to the second media playback speed in real time, and playing the current media content based on the second media playback speed.

2. The method according to claim 1, wherein The step of using the dynamic threshold mapping method to map the filtered rotation frequency to the second media playback speed in real time specifically includes the following steps: Respectively set the upper limits of the low multiple playback control area, the middle multiple playback control area, and the high multiple playback control area of the rotation frequency; Using a three-segment non-linear mapping function to map the filtered rotation frequency value to the second media playback speed; among them, the low multiple playback control area uses an S-shaped curve speed mapping function, the middle multiple playback control area uses a logarithmic curve speed mapping function, and the high multiple playback control area uses an asymptotic saturation curve speed mapping function; when the filtered rotation frequency is within the low multiple playback control area, using the S-shaped curve speed mapping function to map the filtered rotation frequency to the second media playback speed in real time; when the filtered rotation frequency is within the middle multiple playback control area, using the logarithmic curve speed mapping function to map the filtered rotation frequency to the second media playback speed in real time; when the filtered rotation frequency is within the high multiple playback control area, using the asymptotic saturation curve speed mapping function to map the filtered rotation frequency to the second media playback speed in real time.

3. The method according to claim 2, wherein The S-shaped curve speed mapping function is: y = 0.05 + 0.95×(1.0 / (1.0 + exp(-12.0×(x - 0.5)))); The logarithmic curve speed mapping function is: y = 1.0 + 5.0×pow(t, 0.7); The asymptotic saturation curve speed mapping function is: y = 6.0 + 4.0×(1.0 - exp(-(frequency - MID_CUTOFF) / 400.0)); Wherein: y represents the second media playback speed; x = frequency / LOW_CUTOFF; t = (log(frequency) - log(LOW_CUTOFF)) / (log(MID_CUTOFF) - log(LOW_CUTOFF)); MID_CUTOFF represents the upper limit of the middle multiple playback control area, frequency represents the current rotation frequency of the variable-speed playback knob, and LOW_CUTOFF represents the upper limit of the low multiple playback control area.

4. The method according to claim 1, wherein The method for performing real-time debouncing processing using a sliding window mean filter is as follows: Define a filtering window with a fixed size, and arrange the rotation frequencies of the collected variable-speed playback knobs in sequence to form a rotation speed sequence; Move the filtering window to the starting position of the rotational speed sequence, calculate the average value of each rotational frequency signal within this filtering window, and use the average value as the rotational frequency value at the starting position of the rotational speed sequence; Slide the filtering window to the next position of the rotational speed sequence, and also use the average value algorithm to calculate and obtain the rotational frequency value at the next position of the rotational speed sequence; Repeat sliding the filtering window to calculate and obtain the rotational frequency value at each position of the rotational speed sequence.

5. The method according to claim 1, characterized in that, It also includes the following steps: Preset an acceleration threshold α and a deceleration threshold β; Obtain the current rotational frequency of the variable-speed playback knob in real time through the time stamp difference; Based on the comparison result between the rotational frequency change rate within the continuous time window and the preset acceleration threshold α and deceleration threshold β, determine the rotational state of the variable-speed playback knob. The rotational state includes an acceleration state and a deceleration state; when the rotational frequency change rate is greater than α, the rotational state of the variable-speed playback knob is the acceleration state; when the rotational frequency change rate is less than β, the rotational state of the variable-speed playback knob is the deceleration state; In response to the acceleration state, activate the variable-speed control; in response to the deceleration state, freeze the variable-speed control and start monitoring the function keys of the playback console.

6. The method according to claim 1, characterized in that, Adopt an angular binning mapping method to map the rotation frequency after filtering processing to the first media playback speed in real time, which specifically includes the following steps: Divide the rotation angle range of the variable-speed playback knob into multiple playback speed control zones; Preset a fixed first media playback speed for each playback speed control zone respectively; Obtain the rotation angle of the variable-speed playback knob in real time; Based on the playback speed control zone where the rotation angle is located, obtain the current first media playback speed, and play the current media content based on the current first media playback speed.

7. A multimedia variable-speed playback control device based on a physical knob, characterized in that, It includes: A debounce processing module for using a sliding window mean filter to perform debounce processing on the rotation frequency signal of the variable-speed playback knob collected in real time; A first mapping module for, in response to a cruise variable-speed playback mode request, adopting an angular binning mapping method to map the rotation frequency after filtering processing to the first media playback speed in real time; A second mapping module for, in response to a normal variable-speed playback mode request, adopting a dynamic threshold mapping method to map the rotation frequency after filtering processing to the second media playback speed in real time; A playback module for playing the current media content based on the first media playback speed or the second media playback speed.

8. The device according to claim 7, characterized in that, The second mapping module includes: A low multiple playback mapping unit for, when the rotation frequency after filtering processing is within the low multiple playback control zone, using an S-shaped curve speed mapping function to map the rotation frequency after filtering processing to the second media playback speed in real time; A medium multiple playback mapping unit for, when the rotation frequency after filtering processing is within the medium multiple playback control zone, using a logarithmic curve speed mapping function to map the rotation frequency after filtering processing to the second media playback speed in real time; A high multiple playback mapping unit for, when the rotation frequency after filtering processing is within the high multiple playback control zone, using an asymptotic saturation curve speed mapping function to map the rotation frequency after filtering processing to the second media playback speed in real time.

9. The device according to claim 7, characterized in that, It also includes: A state judgment module, configured to judge the rotation state of the variable-speed playback knob according to the comparison result between the rotation frequency change rate within a continuous time window and a preset acceleration threshold α and a preset deceleration threshold β, where the rotation state includes an acceleration state and a deceleration state; when the rotation frequency change rate is greater than α, the rotation state of the variable-speed playback knob is the acceleration state; when the rotation frequency change rate is less than β, the rotation state of the variable-speed playback knob is the deceleration state; An execution module, configured to activate variable-speed control in response to the acceleration state; and in response to the deceleration state, freeze the variable-speed control and start monitoring function keys of the playback console.

10. A computer-readable medium having computer programs / instructions stored thereon, characterized in that, When the computer program / instructions are executed by a processor, the method according to any one of claims 1 to 6 is implemented.

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