US008928752B2
`
`(12) United States Patent
`DeKeyser
`
`(10) Patent No.:
`(45) Date of Patent:
`
`US 8,928,752 B2
`*Jan. 6, 2015
`
`(54) RECORDING DEVICE WITH PRE-START
`SIGNAL STORAGE CAPABILITY
`
`(75) Inventor: Paul DeKeyser, Irvine, CA (US)
`(73) Assignee: Stellar LLC, Irvine, CA (US)
`(*) Notice:
`Subject to any disclaimer, the term of this
`patent 1s ised O lusted under 35
`U.S.C. 154(b) by 1619 days.
`This patent is Subject to a terminal dis-
`claimer.
`
`5,689.442 A 1 1/1997 Swanson et al.
`5,790,427 A
`8, 1998 Greer et al.
`6,163,338 A 12/2000 Johnson et al.
`6,317,817 B1
`1 1/2001 Shichiku et al.
`6,831,652 B1
`12/2004 Orr
`6,950,600 B2
`9, 2005 Dietz
`7,162,607 B2
`1/2007 Macy et al.
`7.263,073 B2 * 8/2007 Petite et al. ................... 370,278
`38.958, A.
`358, San stal
`Zolyga et al.
`2006/0158968 A1* 7/2006 Vanman et al. ............ 369,27.01
`2007, 0132773 A1
`6, 2007 Plante
`2007/0174538 A1
`7/2007 Christoffersson et al.
`FOREIGN PATENT DOCUMENTS
`
`(21) Appl. No.: 11/846,217
`(22) Filed:
`Aug. 28, 2007
`
`(65)
`
`Prior Publication Data
`US 2008/0055410 A1
`Mar. 6, 2008
`ar. O,
`Related U.S. Application Data
`(60) Eyal application No. 60/824,095, filed on Aug.
`s
`(51) Int. Cl.
`H04N 7/8
`G08B I3/96
`(52) U.S. Cl.
`CPC .......... H04N 7/188 (2013.01); G08B 13/19621
`(2013.01); G08B 13/19676 (2013.01)
`USPC .......................................................... 348/148
`(58) Field of Classification Search
`None
`See application file for complete search history.
`
`(2006.01)
`(2006.01)
`
`(56)
`
`References Cited
`U.S. PATENT DOCUMENTS
`
`EP
`O510968
`WO
`99.56216
`* cited by examiner
`
`10, 1992
`11, 1999
`
`Primary Examiner — Nhon Diep
`(74) Attorney, Agent, or Firm — Fish & Tsang LLP
`(57)
`ABSTRACT
`A Surveillance system uses a flash or other memory to store
`multiple data streams, each of which includes pre-start signal
`and post-start signal data. An area of the memory is preferably
`utilized as a circular buffer, in which a second data stream can
`be recorded without overwriting a first data stream. Buffers
`can have sufficient to capacity to capture up to an hour or more
`of image frames. All suitable methods and apparatus for
`initiating start and stop signals are contemplated, including
`for example using a button, toggle or other Switch, a verbal or
`other human interface, and using motion, Sound, light or other
`sensors. It is also contemplated that embodiments can include
`an interface for altering or otherwise designating a pre-signal
`size of the recently used segment. Cameras according to
`present invention can be mounted in any desired manner,
`including for example in camera boxes, on eyeglasses, and on
`automobiles or other vehicle.
`
`1, 1995 Ellson
`5,381.526 A
`5,523,799 A * 6/1996 Hattori et al. ................. 348,715
`
`18 Claims, 5 Drawing Sheets
`
`DeKeyser
`(variable
`buffer)
`
`DeKeyser
`(variable
`buffer)
`
`AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
`AAAAAAAAAAAAAAAAAAAAAAA
`
`AAAAAAAAAAA
`
`

`

`U.S. Patent
`
`Jan. 6, 2015
`
`Sheet 1 of 5
`
`US 8,928,752 B2
`
`Johnson
`(Small
`buffer
`Only)
`
`AAAAA
`
`N 11
`
`Figure 1 (prior art)
`
`Reich
`(Small
`buffer and
`flash)
`
`AAAAA
`N
`21
`
`N
`22
`
`Figure 2A (prior art)
`
`Reich
`(Small
`buffer and
`flash)
`
`AAAAAA AAAAAAAAAAAAAAAAAAAAAAAA
`N
`N
`21
`22
`
`Figure 2B (prior art)
`
`DeKeyser
`(variable
`buffer)
`
`AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
`AAAAAAAAAAAAAAAAAAAAAAA
`
`Figure 3A
`
`

`

`U.S. Patent
`
`Jan. 6, 2015
`
`Sheet 2 of 5
`
`US 8,928,752 B2
`
`DeKeyser
`(variable
`buffer)
`
`AAAAAAAAAAA
`
`/r 30
`
`/r 30
`
`7-30
`
`Figure 3B
`
`AAAAAAAAAAAAAAA
`
`Figure 3C
`
`DeKeyser
`(Variable
`buffer)
`
`DeKeyser
`(variable
`buffer)
`
`AAAAAAAAAAAAAAABBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
`BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
`BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
`BBBBBBB
`
`DeKeyser
`(variable
`buffer)
`
`BBBBBBB
`
`Figure 3D
`
`AAAAAAAAAAAAAAA
`
`Figure 3E
`
`7-30
`
`BBBBBBBBBBBBBBBBBBBBBBBBB
`
`

`

`U.S. Patent
`
`Jan. 6, 2015
`
`Sheet 3 of 5
`
`US 8,928,752 B2
`
`DeKeyser
`(variable
`buffer)
`
`AAAAAAAAAAAAAAA
`
`7-30
`
`BBBBBBBBBBBBBBBBBBB
`
`BBBBBBBBBBBBBBBBBBBBBBBBB
`
`Figure 3F
`
`DeKeyser
`(Variable
`buffer)
`
`CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
`CCCCCCCCCCCCCAAAAAAAAAAAAAAACCCCCC
`
`7-30
`
`BBBBBBBBBBBBBBBBBBBBBBBBB
`BBBBBBBBBBBBBBBBBBBBCCCCCCCCCCCCCCCC. . . CCCCCCCCCCCCCCCCCCC
`
`Figure 3G
`
`DeKeyser
`(variable
`buffer)
`
`CCCCCCCCCCCAAAAAAAAAAAAAAACCCCCC
`
`7-30
`
`BBBBBBBBBBBBBBBBBBB
`
`BBBBBBBBBBBBBBBBBBBBBBBBB
`
`Figure 3H
`
`

`

`U.S. Patent
`
`Jan. 6, 2015
`
`Sheet 4 of 5
`
`US 8,928,752 B2
`
`
`
`BELT-WORN
`RECORDER
`
`DOCKING STATION
`WITH DVD BURNER
`
`46A
`
`46B
`
`47
`
`FIG. 4
`
`

`

`U.S. Patent
`
`Jan. 6, 2015
`
`Sheet 5 of 5
`
`US 8,928,752 B2
`
`50
`
`N
`
`
`
`utilizing an area of a
`memory as a circular buffer
`
`recording a first data stream
`in the buffer
`
`responding to a start Signal
`by protecting a recently used
`Segment of the buffer
`
`recording a Scoond data
`Stream in the buffer
`
`skipping over at least Some
`of the protected Segment
`during recordation of the
`Second data Stream
`
`o
`51A
`storing at least 10 minutes of 1
`image frames in the buffer
`
`51B
`using at least 20% of the 1
`memory as the buffer
`
`51C
`
`the memory storing at least a
`30 second portion of the first
`data Stream, including at
`least a 5 second pre-signal
`portion and at least a 5
`second post-signal portion
`
`the Second data stream is
`continuous with the first data
`Stream
`
`storing at least a 30 Second
`portion of the first data
`Stream in logically dis
`contiguous portions of the
`memory
`
`54A
`
`54B
`
`
`
`56
`
`providing one or more
`interfaces through which a
`user can initiate start and
`Stop signals, and designate a
`pre-signal size of the
`recently used Segment
`
`Figure 5
`
`

`

`1.
`RECORDING DEVICE WITH PRE-START
`SIGNAL STORAGE CAPABILITY
`
`This application claims priority to provisional application
`Ser. No. 60/824,095 filed Aug. 31, 2006.
`
`5
`
`FIELD OF THE INVENTION
`
`The field of the invention is surveillance cameras.
`
`BACKGROUND
`
`10
`
`It is often desirable to record an unexpected event (auto
`mobile accident, baseball hit, quick kiss, facial expression,
`etc), but by the time someone pulls out a camera and focuses 15
`on the target, the momentis gone. This problem has long been
`addressed in the Surveillance industry by recording continu
`ously for long periods of time. It is not unusual, for example,
`for banks or other secure facilities to capture and maintain day
`after day of surveillance tapes. The downside, of course, is 20
`that continuous recordings are costly in terms of equipment,
`storage, bulkiness, and so forth. Moreover, continuous
`recording is especially unsuitable for Small recording devices
`Such as those carried on eyeglasses.
`U.S. Pat. No. 6,163,338 to Johnson et al. (December 2000) 25
`focused on the problem of filming automobile accidents.
`Instead of trying to record millions of frames over long peri
`ods of time, Johnson tried to solve the problem by continu
`ously storing the most recent images in a small looping (cir
`cular) memory. Upon actuation of a trigger, the system 30
`protects the most recently used portion of the memory, and
`overwrites an older portion. Thus, upon receiving a trigger
`signal from an accident, a 30 second memory might end up
`storing 20 seconds before and 10 seconds after the accident.
`A looping memory of a device according to Johnson is 35
`depicted in prior art FIG.1. There a small looping memory 11
`records frames or other data from a data stream 'A'. Each
`character initiates a Small time period, perhaps five seconds,
`with the “I” character designating the current writing posi
`tion. When the memory finishes writing to the last position, it 40
`returns to the first position and over-writes previously stored
`data. Upon receipt of a start signal (such as by actuation of a
`trigger), the memory continues looping for Some period of
`time (corresponding to perhaps a third of the memory capac
`ity), and then stops recording altogether. The recorded 45
`memory is protected until it is offloaded or reset.
`Johnson and all other referenced extrinsic materials are
`incorporated herein by reference in their entirety. Where a
`definition or use of a term in an incorporated reference is
`inconsistent or contrary to the definition of that term provided 50
`herein, the definition of that term provided herein applies and
`the definition of that term in the reference does not apply.
`One problem with Johnson is that the system can only store
`images from a very short time period. US 2004/0033058 to
`Reich et al. (publ. February 2004) contemplates an improve- 55
`ment that tries to solve that problem by using two different
`memories, a small (900 frame) looping buffer and a larger
`flash memory. In Reich, the trigger signal (record button)
`causes the buffer to be completely filled, and then additional
`images to be written to the flash memory until a stop button is 60
`pushed.
`The Reich system is depicted in prior art FIGS. 2A-2B. In
`FIG. 2A, a small looping buffer 21 records data from data
`stream A', with the current position marked with “I”. The
`character is used to initiate memory that has not been 65
`used, or has been used but has been marked for overwriting. In
`FIG. 2B, a start signal has been received, and the system
`
`US 8,928,752 B2
`
`2
`responded by filling the buffer, and then starting to fill a flash
`memory 22. Regardless of whether the flash memory is even
`tually filled, both the buffer 21 and the flash memory 22 are
`effectively locked (protected) upon receipt of a stop signal.
`From FIGS. 1 and 2A-2B, one can readily appreciate that
`both Johnson and Reich can accommodate only a single time
`period. A user cannot record a second event without overwrit
`ing or offloading the stored data from a first event. In addition,
`both Johnson and Reich still contemplate that the looping
`portion memory should be very Small, perhaps 30 seconds or
`less. Such devices are completely inadequate for storing long
`pre-start signal images, such as a five or ten minute period
`prior to a trigger signal.
`Thus, there is still a need for improvements in cameras and
`other surveillance devices that allow recordation of multiple
`events without overwriting or offloading, and that can include
`lengthy portions of data streams prior to start signal events.
`
`SUMMARY OF THE INVENTION
`
`The present invention provides apparatus, Systems and
`methods in which a memory stores multiple data streams,
`each of which includes pre-start signal and post-start signal
`data.
`Preferred embodiments include hardware that executes an
`instruction set that utilizes an area of the memory as a circular
`buffer, records the first data stream in the buffer; responds to
`a signal by protecting a recently used segment of the buffer,
`and records the second data stream in the buffer, without
`overwriting the protected segment. Buffers can be any Suit
`able size, but have sufficient capacity to capture at least 1, 5.
`10, 15, or 20 minutes of image frames (video data), and in
`Some contemplated embodiments have sufficient to capacity
`to capture an hour or more of image frames.
`All practical memories are contemplated, including espe
`cially multi-gigabit removable flash drives. The memory
`preferably utilizes different sections for the buffer at different
`times, with protected Sub-sections being skipped over during
`storage of Subsequent data streams. In some instances that
`may result in a given data stream being stored in logically
`dis-contiguous portions of the memory. Thus, one can con
`sider the memory as having a multiple buffers, or as a single
`buffer of variable size and configuration. At least 20% of the
`memory is preferably used as the buffer.
`All Suitable methods and apparatus for initiating start and
`stop signals are contemplated, including for example using a
`button, toggle or other Switch, a verbal or other human inter
`face, and using motion, Sound, light or other sensors. It is also
`contemplated that embodiments can include an interface for
`altering or otherwise designating a pre-signal size of the
`recently used segment. Default time spans for storing data
`(whether measured in time, number of frames, memory uti
`lized or some other metric) can be advantageously associated
`with start and/or stop signals.
`Cameras according to present invention can be mounted in
`any desired manner, including for example in camera boxes,
`on eyeglasses, and on automobiles or other vehicles.
`Various objects, features, aspects and advantages of the
`present invention will become more apparent from the fol
`lowing detailed description of preferred embodiments of the
`invention, along with the accompanying drawings in which
`like numerals represent like components.
`
`BRIEF DESCRIPTION OF THE DRAWING
`
`FIG. 1 is a schematic of memory usage in prior art devices
`according to Johnson.
`
`

`

`US 8,928,752 B2
`
`3
`FIGS. 2A-2B are schematics of memory usage in prior art
`devices according to Reich.
`FIGS. 3A-3H depict schematics of memory usage in a
`device according to aspects of the present invention, progres
`sively showing storage of multiple data streams.
`FIG. 4 is a schematic of steps for storing multiple data
`streams in a non-contiguous fashion
`FIG. 5 is a schematic of a system using an eyeglasses
`mounted camera to record events.
`
`DETAILED DESCRIPTION
`
`10
`
`4
`unless overridden in some manner, contemplated Systems can
`utilize a default post-start signal period of time for which a
`portion of the data stream is stored unless overridden in some
`manner. Using defaults for both pre-start and post-start signal
`periods allows a system to operate with an extremely high
`level of user convenience. For example, in one contemplated
`class of systems using such defaults, a user could operate a
`single button, ring or other interface to initiate a start signal,
`and the system could respond by automatically storing a
`default 60 second portion of a data stream prior to the signal,
`as well as a default 30 time period of the data stream after the
`signal. And all of that could be accomplished with a single
`operation of the button. As should be apparent from the
`description above, all reasonable the default time periods are
`contemplated.
`In FIG. 3D, the system has finished protecting the desired
`portion of the 'A' data stream, and has now moved on to
`storing a “B” data stream. Of course, the “B” data stream may
`be continuous with the 'A' data stream, so that differentiation
`of 'A' and “B” streams is merely an artifact of how the data
`is being stored. For example, if a system included an eye
`glasses camera being used at baseball game, the wearer might
`watch the game for an hour or more without anything of
`interest happening. During all that time the system would
`record image frames from the camera, looping in memory if
`the memory had remaining capacity for less than an hour of
`images. When finally the wearer sees an interesting play that
`he wants to protect, he operates a start button, and perhaps a
`more time button to protect the previous minute of play. Once
`the interesting action has completed, he operates a stop but
`ton, which thereby causes the system to complete protecting
`the entire “A” period of interest. But the wearer continues
`watching the game, and the Subsequent images, continuous
`with the 'A' images, would be considered “B” images.
`In FIG.3E the system has again received a start signal, and
`again protected a fixed or variable historical time period. In
`FIG. 3F the system has received a stop signal, and has pro
`tected the entire desired portion of the “B” data stream.
`In FIG. 3G the system continued to record data, which is
`now depicted as data stream “C” because it follows data
`stream “B”. This figure is particularly significant in that recor
`dation of the “C” data stream skips over the protected portion
`of the “A” data stream. In FIG. 3H the system received
`another start signal, and has protected a desired portion of the
`“C” data stream that straddles the protected 'A' stream.
`FIG. 4 depicts a system 40 generally comprising eye
`glasses 41 having a camera 42 mounted at the nose bridge,
`and an optional viewfinder 43 applied onto one of the lenses.
`A data and power cord 44 couples the camera 42 to a belt
`worn recorder 46, which cooperates with a ring-shaped sig
`naling device 45 and an off-line docking station with CD
`burner (collectively 47).
`The eyeglasses 41 are used here euphemistically to repre
`sent any type of camera mount, including a fixed or moveable
`Surveillance mount, and also a housing such as a typical
`camera box. Camera 42 should also be interpreted euphemis
`tically to include CCD and all other manner of image obtain
`ing devices, as well as a directional microphone, one or more
`lenses, and so forth. Those skilled in the art will appreciate
`that the term "surveillance' is used herein in its broadest
`possible sense, to include not only professional or commer
`cial types of Surveillance, but also any other type of observa
`tion, including for example an ordinary person watching a
`baseball game or birthday party.
`Recorder 46 is any recording device that records video
`and/or audio/video data, including conventional recorders.
`Recorder 46 preferably include a processor 46A that runs
`
`In FIG. 3A a memory 30 stores data from data stream 'A'
`up to the current position
`marker. The “ character is
`again used to initiate memory that has not been used, or has
`been used but has been marked for overwriting. The ellipsis
`“. . .
`. is used to initiate that the memory can be very large
`relative to the number of positions shown in the figure. It is
`contemplated, for example, that memory 30 can be up to
`several hundred megabytes, 1 GB, 2 GB, 4 GB, 8 GB or even
`more. Such memory is preferably of a flash type, non-volatile
`RAM, preferably in the form of a standard flash memory card.
`In FIG. 3B a recent period of data stream 'A' has been
`protected as a function of a “start” signal, and concomitantly,
`the portion of the data stream prior to the protected portion
`has once again been marked ' ' to shown that it is unpro
`tected. The start signal can be triggered in any suitable man
`ner, including for example manual operation of a trigger by a
`user. In other examples, start signals can be triggered by
`detection of a particular circumstance by a motion, Sound or
`other sensor. In yet another example of a very Sophisticated
`system, software can operate upon content in the data stream,
`Such as by monitoring an entrance to a building using a data
`stream received from one or more cameras, and sending a
`start signal when the images it receives show a person moving
`in a Suspicious manner.
`In protecting recent data, the system can protect a default
`historical time period (such as 30 seconds, 2 minutes, etc),
`and all suitable defaults are contemplated. Alternatively, the
`historical time period being protected could be altered in
`Some manner, such as by Software or by a user operating a
`history button. For example, if a user hits a start button, the
`system might default to protecting the last 30 seconds, and
`then progressively protect prior 30 second periods when the
`user repeatedly hits a “more time' button. In that manner a
`user could protect a 5 or 10 minute period, or an even much
`longer portion of a data stream prior to a start signal. Indeed,
`if memory 30 is interpreted as a multi gigabyte flash memory,
`it is entirely possible that one could back up sufficiently to
`protect an hour or more of Such a data stream.
`In FIG. 3C the system has received a “stop' signal some
`time after receiving the start signal, thereby lengthening the
`protected portion of the 'A' data stream. The stop signal
`could be generated from software or hardware as a function of
`a default time after the start signal. All suitable defaults are
`contemplated, including for example a 30 second or 1 minute
`time period. Stop signals could also be generated in a variable
`fashion, again as a function of Software or hardware, through
`action of a user, or in any other Suitable manner. Thus, a user
`might well operate a start button or other Switch, a more time
`Switch, and a stop Switch, which could have the same or
`different interfaces. It is also contemplated that the system
`could recognize a user's verbal commands for these func
`tions. The system can further comprise a wireless receiver
`upstream of the buffer with respect to the data streams.
`Just as the system can utilize a default pre-start signal
`period of time for which a portion of the data stream is stored
`
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`

`5
`software to accomplish the functions described herein, and
`one or more physical memories that are collectively referred
`to herein as memory 46B. The description of memory 30
`herein can apply equally to memory 46B. Those skilled in the
`art will also appreciate that the concepts described herein
`with respect to video and/or audio/video data can be applied
`to recordation of purely audio, and in fact any other type of
`data stream, and this specification should be interpreted as
`expressly including Such application.
`Although not expressly shown, recorder 46 also includes
`an appropriate power Supply or connection, Supporting elec
`tronics, and a display or other interface. Recorder 46 would
`typically record images in digital format, but analog or com
`bination formats are also contemplated.
`Signaling device 45 is shown in the figure as a ring that
`communicates with the recorder wirelessly. The ring can have
`any Suitable interfaces (not shown), including for example
`buttons on its outer periphery, or a sensor along its inneredge.
`Thus, turning the ring in one direction might produce a start
`signal, and continuing to turn the ring in that direction might
`extend backwards the time period that is protected. Where a
`default time period for storing pre-start signal data is used,
`extending the time can be considered overriding the default.
`Similarly, turning the ring in the opposite direction might
`produce a stop signal, and where a default time period for
`storing post-start signal data is used, extending the time can
`be considered overriding that default. Electronics for such a
`ring or other control device are readily available, and for
`example are similar to those used in key fobs. Indeed, signal
`ing device 45 should be interpreted euphemistically to
`include key fob type devices.
`Docking station and DVD burner 47 can be quite conven
`tional, and can for example include a standard flash memory
`card reader coupled to a home or office PC.
`FIG. 5 shows a method 50 of recording multiple events
`without overwriting or offloading the memory, and including
`potentially lengthy portions of data streams prior to start
`signal events. Contemplated steps include the following,
`which are discussed elsewhere herein:
`Step 51—utilizing an area of a memory as a circular buffer;
`Step 51A—storing at least 10 minutes of image frames in
`the buffer;
`Step 51B using at least 20% of the memory as the buffer;
`Step 51C the memory storing at least a 30 second portion
`of the first data stream, including at least a 5 second
`pre-signal portion and at least a 5 second post-signal
`portion;
`Step 52 recording a first data stream in the buffer;
`Step 53-responding to a start signal by protecting a
`recently used segment of the buffer;
`Step 54 recording a second data stream in the buffer;
`Step 54A the second data stream is continuous with the
`first data stream; Step 54B storing at least a 30 second
`portion of the first data stream in logically dis-contigu
`ous portions of the memory;
`Step 55 skipping over at least some of the protected
`segment during recordation of the second data stream;
`and
`Step 56 providing one or more interfaces through which
`a user can initiate start and stop signals, and designate a
`pre-signal size of the recently used segment.
`Thus, specific embodiments and applications of recording
`devices with pre-start signal storage capability have been
`disclosed. It should be apparent, however, to those skilled in
`the art that many more modifications besides those already
`described are possible without departing from the inventive
`concepts herein. The inventive subject matter, therefore, is
`
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`US 8,928,752 B2
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`6
`not to be restricted except in the spirit of the appended claims.
`Moreover, in interpreting both the specification and the
`claims, all terms should be interpreted in the broadest pos
`sible manner consistent with the context. In particular, the
`terms “comprises” and "comprising should be interpreted as
`referring to elements, components, or steps in a non-exclusive
`manner, indicating that the referenced elements, components,
`or steps may be present, or utilized, or combined with other
`elements, components, or steps that are not expressly refer
`enced. Where the specification claims refers to at least one of
`Something selected from the group consisting of A, B, C . . .
`and N, the text should be interpreted as requiring only one
`element from the group, not A plus N, or B plus N, etc.
`
`What is claimed is:
`1. A Surveillance system comprising:
`a camera that converts images into first and second data
`Streams;
`a memory; and
`hardware that executes an instruction set that utilizes an
`area of the memory as a circular buffer, records the first
`data stream in the buffer; responds to a first signal by
`protecting a recently used segment of the buffer storing
`at least a portion of the first data stream corresponding to
`a duration of time prior to the first signal, while at the
`same time continuously recording the first data stream as
`the second data stream in an unprotected segment of the
`buffer, without overwriting the protected segment; and
`responds to a second signal received after the first signal
`by increasing the duration of the protected segment of
`the buffer prior to the first signal.
`2. The system of claim 1, wherein the buffer stores at least
`10 minutes of image frames.
`3. The system of claim 1, wherein the second data stream is
`continuous with the first data stream.
`4. The system of claim 1, wherein the memory stores at
`least a 30 second portion of the first data stream, including at
`least a 5 second pre-signal portion and at least a 5 second
`post-signal portion.
`5. The system of claim 4, wherein the at least a 30 second
`portion of the first data stream is stored in logically dis
`contiguous portions of the memory.
`6. The system of claim 1, wherein at least 20% of the
`memory is used as the buffer.
`7. The system of claim 1, further comprising a sensor that
`automatically initiates the first signal.
`8. The system of claim 7, wherein the sensor operates upon
`content in the first data stream.
`9. The system of claim 1, further comprising an interface
`through which a human can initiate the signal.
`10. The system of claim 1, further comprising an interface
`through which a human can override a default pre-signal size
`of the recently used segment.
`11. The system of claim 1, further comprising an interface
`through which a human can override a default post-signal size
`of the recently used segment.
`12. The system of claim 1, further comprising a wireless
`receiver upstream of the buffer with respect to the first data
`Stream.
`13. The system of claim 1, further comprising a wearable
`mount for the camera.
`14. The system of claim 1, further comprising a vehicle
`mount for the camera.
`15. The system of claim 1, further comprising a signaling
`device in wireless communication with a recorder comprising
`the memory, and that is configured to wirelessly send the first
`signal to the recorder.
`
`

`

`US 8,928,752 B2
`
`7
`16. The system of claim 15, wherein the wireless signaling
`device comprises a human wearable ring.
`17. The system of claim 15, wherein the wireless signaling
`device comprises a key fob.
`18. The system of claim 15, wherein the wireless signaling 5
`device is local to the camera and the hardware, and local about
`a U.S.
`
`