Method of processing digital video data and image capturing apparatus

Abstract

The invention relates to a method of processing digital video data and an image capture device. A method of processing digital video data is disclosed. A method includes continuously capturing digital video data representing image frames. While capturing digital video data, the digital video data is encoded into a sequence of encoded image frames and the sequence of encoded image frames is stored, the sequence comprising key frames and delta frames. It is then determined that the stored sequence of encoded image frames is to be entropy-encoded, and therefore, the sequence of encoded image frames is entropy-encoded into an entropy-encoded sequence of image frames and the entropy-encoded sequence of image frames is stored.

Description

Technical Field

[0001] The present invention relates to the processing of digital video data representing a sequence of captured image frames and to an image capture device comprising circuitry configured to perform such processing. Background Art

[0002] A trend in the development of image capture devices (i.e., cameras) capable of capturing video data is the need for high image resolution and high image quality in terms of, for example, dynamic range and high quality color representation, while minimizing the amount of data required to represent such high image quality. In order to meet these demands, various algorithms have been developed over the past several decades, with each generation of algorithms being more complex than the previous generation. As a result, the demand for higher and higher processing power in cameras continues to increase. Noting that most types of cameras are battery powered, the development of image capture devices faces the inevitable problem of a trade-off between high quality and the amount of energy available to power the camera. Summary of the invention

[0003] It is of interest to provide a method which overcomes the disadvantages discussed above. In a first aspect, this and other objects are achieved by providing a method having the features of the attached independent claims. Preferred embodiments are defined in the attached dependent claims.

[0004] Therefore, according to a first aspect, a method of processing digital video data is provided. The method comprises continuously capturing digital video data representing image frames. While capturing the digital video data, the digital video data is encoded into a sequence of encoded image frames and the sequence of encoded image frames is stored, the sequence comprising key frames and incremental frames. It is then determined that the stored sequence of encoded image frames is to be entropy encoded, and therefore, the sequence of encoded image frames is entropy encoded into an entropy encoded sequence of image frames and the entropy encoded sequence of image frames is stored.

[0005] Encoding of digital video data into a sequence of encoded image frames may be performed by an encoder operating according to any of the standards H.264 specified by the International Telecommunication Union Telecommunication Standardization Sector (ITU-T), H.265 specified by ITU-T, Advanced Video Coding (AVC) specified by the International Organization for Standardization and the International Electrotechnical Commission Joint Technical Committee (ISO / IEC JTC1), High Efficiency Video Coding (HEVC) specified by ISO / IEC JTC1, and AOMedia Video1 (AV1) specified by the Alliance for Open Media (AOMedia).

[0006] By introducing a step of determining that the sequence of stored coded image frames is to be entropy encoded, the generation of the sequence of coded image frames and the entropy encoding (i.e., compression) of the sequence of coded image frames can be separated in time. Such time can be minutes, hours, or even days. This allows the device performing the method to reduce the use of processing power while operating under a limited power budget. Such a limited power budget can be used, for example, when running on battery power or when the battery power is below a threshold (e.g., less than 20%). The reduction in power use stems from the fact that the method makes it possible to postpone entropy encoding that requires power to a later point in time. For example, entropy encoding can be postponed until the device is no longer subject to power usage restrictions, such as when powered by an external power supply. Therefore, the introduction of the postponement of entropy encoding is conducive to maximizing the operating time for capturing video data and encoding the captured video data into a sequence of coded image frames. This is because when the device is operating under a limited power budget, battery power can be saved by not performing entropy encoding.

[0007] Determining that the sequence of stored encoded image frames is to be entropy encoded may include receiving a trigger signal. Receiving the trigger signal may include receiving the signal via a user interface in the image capture device performing the method. Alternatively or in combination, receiving the trigger signal may include receiving information indicating that the image capture device performing the method is operating according to a power budget that currently allows entropy encoding. Alternatively or in combination, receiving the trigger signal may include receiving a signal indicating that the image capture device performing the method is operating under external power.

[0008] Thus, the trigger for entropy encoding the sequence of stored encoded image frames may be an action taken by a user via a user interface, or may be a more automatic action such as detecting that the device has been connected to an external power source such as a battery charger or docking station. An example of a use case involving an action taken by a user via a user interface is a use case where the user decides that entropy encoding is necessary, even though this will result in an increase in power usage.

[0009] The entropy encoding of the sequence of coded image frames into the entropy coded sequence of image frames and the storage of the entropy coded sequence of image frames may be performed by an image capture device that captures the digital video data. Alternatively, the sequence of coded image frames may be provided from the image capture device to the processing system. The entropy encoding of the sequence of coded image frames into the entropy coded sequence of image frames and the storage of the entropy coded sequence of image frames may then be performed by the processing system.

[0010] Thus, upon being triggered, the entropy encoding and storage of the entropy coded sequence of image frames may be performed locally by the image capture device itself, or externally in a processing system to which the image capture device provides the stored sequence of coded image frames. This alternative provides the option of utilizing the typically very large processing and storage capabilities of a server or cloud-based system to entropy encode and store the entropy coded sequence of image frames.

[0011] The method may be initiated because the capture of digital video data is initiated as a result of receiving an initiation signal. For example, when executed in an image capture device, the receipt of the initiation signal may include any of receiving a signal via an input / output interface in the image capture device, receiving information indicating that the image capture device is operating according to a power budget that does not currently allow entropy encoding, receiving a signal indicating that the image capture device is operating under internal battery power, receiving a signal indicating an event detected in audio content recorded by the image capture device, receiving a signal indicating a changed connection state of a positioning function of the image capture device, and receiving a signal indicating a changed connection state of a data communication function of the image capture device.

[0012] Thus, the method may be triggered manually by a user or in a more automated manner based on information such as power budget or real-time events detected by the image capture device itself during operation.

[0013] In a second aspect, an image capture device is provided, the image capture device comprising a circuit configured to continuously capture digital video data representing image frames. The circuit is further configured to encode the digital video data into a sequence of encoded image frames and store the sequence of encoded image frames in a non-volatile memory of the image capture device while capturing the digital video data, the sequence including key frames and incremental frames. The circuit is further configured to determine that the stored sequence of encoded image frames is to be entropy encoded, and therefore, entropy encode the sequence of encoded image frames into an entropy encoded sequence of image frames, and store the entropy encoded sequence of image frames. The storage of the entropy encoded sequence of image frames can be performed in the non-volatile memory of the image capture device. Alternatively or in combination, the storage of the entropy encoded sequence of image frames can be performed in a cloud-based storage or on a server connected to the image capture device.

[0014] The circuitry of the image capture device may be configured such that determining that the stored sequence of encoded image frames is to be entropy encoded comprises receiving a trigger signal.

[0015] The circuitry of the image capture device may be configured such that entropy encoding of the sequence of encoded image frames into an entropy encoded sequence of image frames and storing of the entropy encoded sequence of image frames are performed by the image capture device.

[0016] The circuitry of the image capture device may be configured such that capture of digital video data is initiated as a result of receiving an initiation signal.

[0017] The circuitry of the image capture device can be configured such that receipt of the start signal includes any of receiving a signal via input / output circuitry in the image capture device, receiving information indicating that the image capture device is operating according to a power budget that currently does not allow entropy encoding, receiving a signal indicating that the image capture device is operating under internal battery power, receiving a signal indicating an event detected in audio content recorded by the image capture device, receiving a signal indicating a changed connection state of a positioning function of the image capture device, and receiving a signal indicating a changed connection state of a data communication function of the image capture device.

[0018] The circuitry of the image capture device may be configured such that encoding of the digital video data into a sequence of encoded image frames is performed by an encoder operating according to any of the standards H.264 specified by ITU-T, H.265 specified by ITU-T, AVC specified by ISO / IEC JTC1, HEVC specified by ISO / IEC JTC1, and AV1 specified by AOMedia.

[0019] The image capture device may be in the form of a body worn camera (BWC). BWCs may be used by law enforcement personnel and as such are typically worn and operated for long periods of time without an external power supply. It would therefore be advantageous if the image capture device could operate as summarised above and thereby ensure that the capture of video data can be performed over a long period of time.

[0020] Such an image capturing device provides effects and advantages corresponding to those summarized above in connection with the method according to the first aspect.

[0021] Further scope of applicability of the present invention will become apparent from the detailed description given below. However, it should be understood that while indicating the preferred embodiments of the present invention, the detailed description and specific examples are given by way of illustration only, because various changes and modifications within the scope of the present invention will become apparent to those skilled in the art from the detailed description.

[0022] Therefore, it should be understood that the present invention is not limited to the particular components of the described device or the actions of the described method, because such device and method can vary. It should also be understood that the terms used herein are only used for the purpose of describing a particular embodiment and are not intended to be restrictive. It must be noted that the articles "a", "an", "the" and "said" as used in the specification and the appended claims are intended to mean that there are one or more elements, unless the context clearly indicates otherwise. Therefore, for example, reference to "a device" or "said device" can include multiple devices, etc. In addition, the words "comprising", "including" and "containing" do not exclude other elements or steps. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The above and other aspects of the present invention will now be described in more detail with reference to the accompanying drawings. The drawings should not be considered limiting; rather, they are for explanation and understanding. Like reference numerals refer to like elements throughout.

[0024] Figure 1a schematically illustrates an image capture device,

[0025] Figure 1b schematically illustrates a body-worn camera, and

[0026] Figure 2 is a flow chart of the method. DETAILED DESCRIPTION

[0027] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which currently preferred embodiments of the present invention are shown. However, the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided to be thorough and complete and to fully convey the scope of the invention to those skilled in the art.

[0028] Figure 1a An image capture device 100 is illustrated that includes circuitry in the form of an image detector 101 , processing circuitry 102 , memory 103 , and input / output (I / O) circuitry 104 .

[0029] In addition to the necessary optical components, the image detector 101 may also include a detector chip and a suitably configured interface circuit configured to provide detector data to the processing circuit 102 .

[0030] The processing circuit 102 of the image capture device 100 is configured to perform overall control of the functions and operations of the image capture device. The processing circuit 102 may include a processor such as a central processing unit (CPU), a microcontroller or a microprocessor, and an application specific integrated circuit (ASIC) or similar circuit. The processor is configured to execute program code stored in the memory 103 to perform the functions and operations of the image capture device 100.

[0031] The memory 103 may be one or more of a buffer, a flash memory, a hard drive, a removable medium, a volatile memory, a non-volatile memory, a random access memory (RAM), or another suitable device. In a typical arrangement, the memory 103 may include a non-volatile memory for long-term data storage and a volatile memory used as a system memory for the processing circuit 102. The memory 103 may exchange data with the processing circuit 102 via a data bus. There may also be accompanying control lines and an address bus between the memory 103 and the processing circuit 102.

[0032] The functions and operations of the image capture device 100 may be embodied in the form of executable logic routines (e.g., lines of code, software programs, etc.) that are stored on a non-transitory computer-readable medium (e.g., memory 103) of the image capture device 100 and executed by the processing circuit 102 (e.g., using a processor). In addition, the functions and operations of the image capture device 100 may be stand-alone software applications or form part of a software application that performs additional tasks related to the image capture device 100. The functions and operations described may be considered as methods that the corresponding parts of the device are configured to perform. Likewise, although the functions and operations described may be implemented in software, such functions may also be performed via dedicated hardware or firmware, or some combination of hardware, firmware and / or software.

[0033] The image capture device 100 is configured to continuously capture digital video data representing image frames via an image detector 101. When capturing the digital video data, the image capture device 100 is configured to encode the digital video data into a sequence of encoded image frames. The sequence of encoded image frames includes key frames and incremental frames. The encoding is typically performed in the processing circuit 102. The image capture device 100 is configured to store the sequence of encoded image frames in the memory 103. More specifically, the image capture device 100 is configured to store the sequence of encoded image frames in a non-volatile portion of the memory 103.

[0034] The image capture device 100 is further configured to determine that the stored sequence of encoded image frames is to be entropy encoded.

[0035] Determining that the sequence of stored encoded image frames is to be entropy encoded may include receiving a trigger signal. The trigger signal may be received as a signal of a user interface via an I / O circuit 104 in the image capture device 100. Alternatively or in combination, the trigger signal may be information indicating that the image capture device 100 is operating according to a power budget that currently allows entropy encoding. Such information may be created, for example, in the form of a predetermined setting (e.g., stored in the memory 103). Alternatively or in combination, the trigger signal may be a signal indicating that the image capture device 100 is operating under external power. Such a signal may be based on the detection of the image capture device 100 being connected to the docking station 106. Such detection may be achieved by the I / O circuit 104 detecting, via the switch 107, whether there is a connection between the image capture device 100 and the docking station 107, and the docking station 107 may be provided with power from the external power supply 111.

[0036] Entropy encoding the sequence of encoded image frames into an entropy encoded sequence of image frames may be performed by the image capture device 100. Alternatively or in combination, the sequence of encoded image frames may be provided from the image capture device 100 to the processing system 110. Entropy encoding the sequence of encoded image frames into an entropy encoded sequence of image frames may then be performed by the processing system 110. The entropy encoded sequence of image frames may be stored locally at the image capture device 100. The memory storing the entropy encoded sequence of image frames may be the memory 103 of the image capture device 100. Alternatively, a memory external to the image capture device 100 (such as a cloud-based memory and / or a memory of a server) may be used to store the entropy encoded sequence of image frames.

[0037] The processing system 110 may be a server arrangement to which the image capture device 100 is connected. Such connection may be achieved through the I / O circuitry 104 and via, for example, a docking station 106. Figure 1a As illustrated, other connection paths with external processing systems may be implemented through the I / O circuitry 104 including wireless communication capabilities, via the air interface 113 to the cloud-based system 112. The processing system disposed in the cloud-based system 112 may then be configured to perform entropy encoding of the sequence of encoded image frames into an entropy encoded sequence of image frames and storage of the entropy encoded sequence of image frames.

[0038] The capture of digital video data may be initiated as a result of receiving an initiation signal. For example, the image capture device 100 may be configured such that the receipt of the initiation signal includes any of the following:

[0039] The signal is received via I / O circuitry 104 in image capture device 100. For example, I / O circuitry 104 may include a user interface including a touch display capable of detecting and communicating a user action in the form of touching a "start" button.

[0040] Information indicating that the image capture device 100 is operating according to a power budget that does not currently allow entropy encoding is received. For example, such information may be created, for example, in the form of predetermined settings (eg, stored in the memory 103).

[0041] A signal is received indicating that the image capture device 100 is operating under internal battery power. For example, the I / O circuit 104 may be configured such that it can detect, via the switch 107, that the image capture device 100 is disconnected from the dock 106 .

[0042] A signal is received indicating an event detected in the audio content recorded by the image capture device 100. For example, the I / O circuitry 104 may include a microphone for recording concurrent audio data during the capture of video data. The processing circuitry 102 may then be configured to analyze the audio data and thereby determine, for example, that a user issued a voice command, or that a specific audio noise or alarm pattern was recognized.

[0043] A signal is received indicating a changed connection state of a positioning function of the image capture device 100. For example, the I / O circuitry 104 may include positioning circuitry, such as a global positioning system (GPS) circuitry, for determining the location of the image capture device 100 during the capture of video data. The processing circuitry 102 may then be configured to analyze output data of the positioning circuitry and thereby determine, for example, that the image capture device 100 is unable to determine its location.

[0044] A signal is received indicating a changed connection state of a data communication function of the image capture device 100. For example, the I / O circuit 104 may include a wireless communication circuit for communicating via a mobile communication network. The processing circuit 102 may then be configured to analyze the output data of the wireless communication circuit and thereby determine, for example, that the image capture device 100 is unable to communicate.

[0045] Figure 1b An embodiment of an image capture device 100 in the form of a body worn camera (BWC) positioned and worn by a person 120 is illustrated.

[0046] Now go to Figure 2 , and continue to refer to Figure 1a and Figure 1b , the method of processing digital video data will be described in more detail. As described above, the method may be performed by an executable logic routine (eg, code lines, software program, etc.) stored in the memory 103 of the image capture device 100 and executed by the processing circuit 102.

[0047] The method of processing digital video data comprises a capturing step 203 of continuously capturing digital video data representing image frames. While capturing the digital video data, the digital video data is encoded into a sequence of encoded image frames in an encoding step S205, the sequence comprising key frames and incremental frames. While continuing the capturing step S203, the sequence of encoded image frames is stored in a storing step S207. Typically, the storing of the sequence of encoded image frames is performed in a non-volatile memory, preferably at the device performing the capturing of the digital video data. At a later point in time, typically in the order of minutes, hours or even days, a determination is made in a determining step S209 that the stored sequence of encoded image frames is to be entropy encoded. As a result, the sequence of encoded image frames is entropy encoded into an entropy encoded sequence of image frames in an entropy encoding step S211. The entropy encoded sequence of image frames is stored in a storing step S213.

[0048] In the encoding step S205, encoding of the digital video data into a sequence of encoded image frames may be performed by an encoder operating according to any of the standards H.264 specified by the International Telecommunication Union Telecommunication Standardization Sector (ITU-T), H.265 specified by the ITU-T, Advanced Video Coding (AVC) specified by the International Organization for Standardization and the International Electrotechnical Commission Joint Technical Committee (ISO / IEC JTC1), High Efficiency Video Coding (HEVC) specified by ISO / IEC JTC1, and AOMedia Video1 (AV1) specified by the Alliance for Open Media (AOMedia).

[0049] In the determination step S209, determining that the sequence of stored encoded image frames is to be entropy encoded may include receiving a trigger signal. For example, when performed in the image capture device 100, the receiving of the trigger signal may include any of receiving a signal via the user interface 104 in the image capture device, receiving information indicating that the image capture device is operating according to a power budget that currently allows entropy encoding, and receiving a signal indicating that the image capture device 100 is operating under external power.

[0050] When performed in the image capture device 100, entropy encoding the sequence of encoded image frames into the entropy encoded sequence of image frames in the entropy encoding step S211 and storing the entropy encoded sequence of image frames in the storage step S213 may be performed by the image capture device 100. Alternatively, when performed in the image capture device 100, in the providing step S210, the sequence of encoded image frames may be provided from the image capture device 100 to the processing system 110, and entropy encoding the sequence of encoded image frames into the entropy encoded sequence of image frames in the encoding step 211 and storing the entropy encoded sequence of image frames in the storage step 213 may be performed by the processing system 110.

[0051] In various embodiments, the entropy encoding step S211 and the storing step S213 may be performed partially by the image capture device 100 and partially by the processing system 110. In such embodiments, only a portion of the sequence of encoded image frames may be provided from the image capture device 100 to the processing system 110.

[0052] The initiation of the capture of the digital video data in the capturing step S203 may be performed as a result of receiving the start signal in the receiving step S201. For example, when performed in the image capture device 100, receiving the start signal in the receiving step S201 may include any of the following items:

[0053] The signal is received via I / O circuitry 104 in image capture device 100. For example, I / O circuitry 104 may include a user interface including a touch display capable of detecting and communicating a user action in the form of touching a "start" button.

[0054] Information indicating that the image capture device 100 is operating according to a power budget that does not currently allow entropy encoding is received. For example, such information may be created, for example, in the form of predetermined settings (eg, stored in the memory 103).

[0055] A signal is received indicating that the image capture device 100 is operating under internal battery power. For example, the I / O circuit 104 may be configured such that it can detect, via the switch 107, that the image capture device 100 is disconnected from the dock 106 .

[0056] A signal is received indicating an event detected in audio content recorded by the image capture device 100. For example, the I / O circuitry 104 may include a microphone for recording concurrent audio data during the capture of video data. The audio data may be analyzed and it may be determined that, for example, a user issued a voice command, or that a specific audio noise or alarm pattern was recognized.

[0057] A signal is received indicating a changed connection state of a positioning function of the image capture device 100. For example, the I / O circuit 104 may include a positioning circuit, such as a global positioning system (GPS) circuit, for determining the location of the image capture device 100 during the capture of video data. The output data of the positioning circuit may be analyzed, and thereby it may be determined that, for example, the image capture device 100 cannot determine its location.

[0058] A signal indicating a changed connection state of a data communication function of the image capture device 100 is received. For example, the I / O circuit 104 may include a wireless communication circuit for communicating via a mobile communication network. The output data of the wireless communication circuit may be analyzed, and thereby it may be determined that, for example, the image capture device 100 cannot communicate.

[0059] Those skilled in the art realize that the present invention is by no means limited to the preferred embodiments described above. On the contrary, many modifications and variations are possible within the scope of the appended claims.

[0060] Additionally, variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims.

Claims

1. A method of processing digital video data performed in an image capture device, the method comprising: continuously capturing digital video data representing image frames; encoding the digital video data into a sequence of coded image frames and storing the sequence of coded image frames while capturing the digital video data, the sequence including key frames and delta frames, Determining that a stored sequence of encoded image frames is to be entropy encoded, and thereby entropy encoding the sequence of encoded image frames into an entropy encoded sequence of image frames, and storing the entropy encoded sequence of image frames, wherein determining that the stored sequence of encoded image frames is to be entropy encoded includes receiving a trigger signal, and wherein receiving the trigger signal includes receiving a signal indicating that the image capture device is operating under external power.

2. The method according to claim 1, wherein: The receiving of the trigger signal includes any of the following: receiving a signal via a user interface in the image capture device, Information is received indicating that the image capture device is operating according to a power budget that currently allows entropy encoding.

3. The method according to claim 1, wherein: Entropy encoding of the sequence of encoded image frames into an entropy encoded sequence of image frames and storing of the entropy encoded sequence of image frames are performed by the image capture device.

4. The method of claim 1 , comprising providing the sequence of encoded image frames from the image capture device to a processing system, and wherein: Entropy encoding the sequence of encoded image frames into an entropy encoded sequence of image frames and storing the entropy encoded sequence of image frames are performed by the processing system.

5. The method according to any one of claims 1 to 4, wherein: The capturing of the digital video data is initiated as a result of receiving an initiation signal.

6. The method according to claim 5, wherein the method is performed in an image capture device, The receiving of the start signal includes any of the following: receiving a signal via an input / output circuit in the image capture device, receiving information indicating that the image capture device is operating according to a power budget that does not currently allow entropy encoding, receiving a signal indicating that the image capture device is operating under internal battery power, receiving a signal indicative of an event detected in audio content recorded by the image capture device, receiving a signal indicative of a changed connection state of a positioning circuit that determines a position of the image capture device, A signal is received indicating a changed connection status of wireless communication circuitry of the image capture device.

7. The method according to claim 1, wherein: Encoding the digital video data into a sequence of encoded image frames is performed by an encoder operating according to any of the following: H.264, specified by the International Telecommunication Union's telecommunication standardization sector ITU-T, H.265, specified by ITU-T, Advanced Video Coding AVC is specified by the Joint Technical Committee of the International Organization for Standardization and the International Electrotechnical Commission ISO / IEC JTC1. High Efficiency Video Coding (HEVC) specified by ISO / IEC JTC1, and AOMedia Video1AV1 specified by the Alliance for Open Media AOMedia.

8. An image capture device comprising a circuit, the circuit being configured to: continuously capturing digital video data representing image frames; encoding the digital video data into a sequence of coded image frames and storing the sequence of coded image frames while capturing the digital video data, the sequence including key frames and delta frames, determining that the stored sequence of coded image frames is to be entropy coded, and thus entropy encoding the sequence of coded image frames into an entropy coded sequence of image frames, and storing the entropy coded sequence of image frames, wherein The circuit is configured such that: Determining that the stored sequence of encoded image frames is to be entropy encoded includes receiving a trigger signal indicating that the image capture device is operating under external power.

9. The image capture device according to claim 8, wherein: The circuit is configured such that: Entropy encoding of the sequence of encoded image frames into an entropy encoded sequence of image frames and storing of the entropy encoded sequence of image frames are performed by the image capture device.

10. The image capture device according to any one of claims 8 to 9, wherein: The circuit is configured such that: The capturing of the digital video data is initiated as a result of receiving an initiation signal.

11. The image capture device according to claim 10, wherein: The circuit is configured such that: The receiving of the start signal includes any of the following: receiving a signal via an input / output circuit in the image capture device, receiving information indicating that the image capture device is operating according to a power budget that does not currently allow entropy encoding, receiving a signal indicating that the image capture device is operating under internal battery power, receiving a signal indicative of an event detected in audio content recorded by the image capture device, receiving a signal indicative of a changed connection state of a positioning circuit that determines a position of the image capture device, A signal is received indicating a changed connection status of wireless communication circuitry of the image capture device.

12. The image capture device according to claim 8, wherein: The circuit is configured such that: Encoding the digital video data into a sequence of encoded image frames is performed by an encoder operating according to any of the following: H.264, specified by the International Telecommunication Union's telecommunication standardization sector ITU-T, H.265, specified by ITU-T, Advanced Video Coding AVC is specified by the Joint Technical Committee of the International Organization for Standardization and the International Electrotechnical Commission ISO / IEC JTC1. High Efficiency Video Coding (HEVC) specified by ISO / IEC JTC1, and AOMedia Video1AV1 specified by the Alliance for Open Media AOMedia.

13. The image capture device of claim 8, the image capture device being a body worn camera (BWC).

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