Abstract:
Provided are methods, processing systems and media content devices for associating a device clock from a media content device and a reference time external to the media content device for: receiving media content containing a representation of the reference time; determining a timestamp derived from the device clock, wherein the timestamp is associated with the received media content; and reconstructing the reference time from the media content.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     Not Applicable.  
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
       [0002]     Not Applicable.  
       REFERENCE TO A COMPACT DISK APPENDIX  
       [0003]     Not Applicable.  
       BACKGROUND OF THE INVENTION  
       [0004]     1. Field of the Invention  
         [0005]     The present invention relates generally to compensating for discrepancies between a time on a media device and a reference time, and specifically though not exclusively to synchronizing media content from such a media device or devices.  
         [0006]     2. Description of the Related Art  
         [0007]     Audio, video and image content from media capture devices, such as digital camera (providing still images), digital video cameras (providing audio/video moving images and/or video only moving images), audio recorders such as in digital players or advanced keyboards (providing audio tracks) and combination media devices (providing still images, audio and/or video), are shared more and more frequently. Many of these media capture devices have an internal clock used to timestamp content as it is collected. The timestamp may represent a time of day, a date, or a combined date and time, each referred to simply as “time” below.  
         [0008]     Often a user is required to set the internal device clock manually, which may be a cumbersome, burdensome, non-intuitive or inconvenient process. In any case, a device&#39;s internal clock may be off by a few seconds, a few minutes or might not be set at all and reflect only the duration of time since that device was activated. Furthermore, the device time may drift over the lifetime of the device. For these reasons, the device&#39;s internal clock usually does not precisely reflect the absolute time.  
         [0009]     For example, in the latest models of digital cameras, the burden of setting the clock correctly is inflicted upon the camera owner. As a consequence, the digital camera clock is often not set correctly and does not reflect the correct time. In addition, time-aligning photos from different cameras compounds the problem, as each camera provides a different time.  
         [0010]     With respect to cameras and photos, current solutions require users to manually adjust capture times or to manually synchronize photos from disparate cameras, for example, by visual inspection of each photo&#39;s content or adjusting time directly on the camera. Even if users undertake this manual time adjustment process, in order to synchronize multiple users&#39; photos, users need to set the clocks precisely to a common time and time zone for each camera, which may be a considerably challenging task.  
         [0011]     Devices may integrate an inaccurate timestamp with the content and/or may keep it separate from the content. For example, the timestamp may be integrated within the collected content itself, such as a date/time overlaying at the bottom corner of a photograph. As another example, the timestamp may be apart from but associated with the collected content, such as in a file containing both the content in the file&#39;s body and metadata in the file&#39;s header. The metadata may include one or more time fields such as date, time of day and duration of when the content was created or modified.  
         [0012]     The present invention seeks to alleviate one or more issues resulting from multiple clocks internal to and external from one or more media capture devices.  
       BRIEF SUMMARY OF THE INVENTION  
       [0013]     Embodiments of the present invention provide a method, processing system or media content device for associating a device clock from a media content device and a reference time external to the media content device. Some embodiments of the present invention further provide for receiving media content containing a representation of the reference time; determining a timestamp derived from the device clock, wherein the timestamp is associated with the received media content; and reconstructing the reference time from the media content.  
         [0014]     Some embodiments of the present invention further provide for correlating the timestamp and the reconstructed reference time, for example, wherein correlating the timestamp and the reconstructed reference time comprises computing a difference between the timestamp and the reconstructed reference time, and/or wherein the media content comprises a video, and/or wherein the media content comprises a photographic image, and/or wherein determining the timestamp comprises extracting one or more time parameters from a header associated with the media content, and/or wherein determining the timestamp comprises determining the timestamp from a file creation time, and/or wherein reconstructing the reference time comprises decoding a bar code, and/or wherein the bar code comprises a two-dimensional (2-D) bar code.  
         [0015]     Some embodiments of the present invention further provide for reconstructing the reference time comprises performing optical character recognition (OCR) on at least a portion of the media content, and/or selecting a set of media content based on one or more configuration parameters, for example, wherein at least one of the one or more configuration parameters comprises a time span, and/or wherein at least one of the one or more configuration parameters comprises one or more uploading events, and/or setting an adjusted time associated with the media content based on at least one of the one or more configuration parameters.  
         [0016]     Some embodiments of the present invention further provide for setting an adjusted time associated with the media content based on the computed difference. Some embodiments of the present invention further provide for setting an adjusted time associated with the media content based on the timestamp and the reconstructed reference time. Some embodiments of the present invention further provide for detecting whether or not a portion of the received media content contains a representation of a reference time, and/or receiving additional media content void of the representation of the reference time, for example, for detecting that the additional media content is void of the representation of the reference time, and/or setting an adjusted time associated with the additional media content based on the timestamp and the reconstructed reference time, and/or wherein the reference time represents a universal coordinated time, and/or wherein the reference time comprises a local time. Some embodiments of the present invention further provide generating the representation of the reference time and/or providing the representation of the reference time to a web page.  
         [0017]     The invention provides several ways to correct the image times by determining the offset, and adding/subtracting the offset to a collection of images taken with a digital camera. The fundamental goal is to provide a link between the time on the server and the time on the device. Several methods are described below.  
         [0018]     Other features and aspects of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings which illustrate, by way of example, the features in accordance with embodiments of the invention. The summary is not intended to limit the scope of the invention, which is defined solely by the claims attached hereto. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0019]      FIG. 1  shows an exemplary system for time synchronization of media content, in accordance with some embodiments of the present invention.  
         [0020]      FIGS. 2A through 2E  presents user and system process flows, in accordance with some embodiments of the present invention.  
         [0021]      FIG. 3  presents another process flow, in accordance with some embodiments of the present invention.  
         [0022]      FIG. 4  illustrates an example screenshot showing an encoded 2-dimensional (2-D) barcode representation of a reference time, in accordance with some embodiments of the present invention.  
         [0023]      FIG. 5  illustrates an example image captured by a media capture device of the screenshot of  FIG. 4 , in accordance with some embodiments of the present invention.  
         [0024]      FIG. 6  shows information associated with a captured image, in accordance with some embodiments of the present invention.  
         [0025]      FIG. 7  shows information associated with a processed image, in accordance with some embodiments of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0026]     In the following description, reference is made to the accompanying drawings which illustrate several embodiments of the present invention. It is understood that other embodiments may be utilized and mechanical, compositional, structural, electrical, and operational changes may be made without departing from the spirit and scope of the present disclosure. The following detailed description is not to be taken in a limiting sense, and the scope of the embodiments of the present invention is defined only by the claims of the issued patent.  
         [0027]     Some portions of the detailed description that follows are presented in terms of procedures, steps, logic blocks, processing, and other symbolic representations of operations on data bits that can be performed on computer memory. A procedure, computer executed step, logic block, process, etc., are here conceived to be a self-consistent sequence of steps or instructions leading to a desired result. The steps are those utilizing physical manipulations of physical quantities. These quantities can take the form of electrical, magnetic, or radio signals capable of being stored, transferred, combined, compared, and otherwise manipulated in a computer system. These signals may be referred to at times as bits, values, elements, symbols, characters, terms, numbers, or the like. Each step may be performed by hardware, software, firmware, or combinations thereof.  
         [0028]     In some embodiments of the present invention, a user views a web page that lists the time of a server and manually inputs the time that is displayed on their media content device onto the web page. When the user submits this information, a link is established between the time entered from the media content device clock and the time on the server.  
         [0029]     In some embodiments of the present invention, a users take a picture on an image encoded with a reference time, for example, a reference time from a server. Therefore, a timestamp derived from the media content device clock and the reference time are encoded together. Thereafter, a user may later upload the image for processing. In addition, the reference time encoded in the captured image from and the media capture device clock are accurate coordinated. The uploaded content may also contain additional useful metadata without any user intervention or input. The media content device and the server perform the otherwise cumbersome tasks of reconciling discrepancies in various clocks.  
         [0030]     For example, a server provides the user with an image encoded with the server time in GMT. The time is written on the screen and is also encoded in a bar code. So that the time will be accurate, the page refreshes the image every couple of seconds. The users then take a picture of this screen, thereby encoding the image on the digital camera with the image embedded in the barcode. The user then uploads this image to the server using the upload screen. The server then uses an image parsing algorithm to parse out the GMT time embedded in the barcode. Alternately, the image parsing algorithm could use OCR to parse out the text as well.  
         [0031]     An image taken by a digital camera may have an “EXIF” header including the date and time. In this case, deriving a time offset may require the server to read the date and time embedded in the EXIF header of the uploaded image. In some cases, the image may not hold an EXIF header and therefore the time of the image capture most be obtained from the file creation time. The information in the photo&#39;s metadata header (EXIF) may tell a system what is the camera clock time at the moment the photo was taken (exposureCamClock) for example as a timestamp. The offset between the accurate reference time and the camera time, CamOffset =exposureUTC−exposureCamClock, can be then applied by the system to all photos from the same camera.  
         [0032]     When an image is uploaded through the web, the file creation time on the server is the time that the image was uploaded. Since this may be different than the actual time that the image was taken on the digital camera, there may be a way to preserve the file creation time for the image when the image is created. This preservation may be accomplished by a client application that resides on the user&#39;s machine. The client application may accept images with embedded time information.  
         [0033]     When the digital camera is connected to the user&#39;s machine, the user may drag or copy the images to the client application. Because the images are on the same file system, the client application recognizes and preserves the file creation time. The client application then performs the same or similar image analysis as may otherwise be performed on a server, for example, parsing the image for the GMT time and any additional meta-data. In the case that there is no EXIF header information (or other type of metadata), the file creation time may be used. After this timing or clock information is obtained, an offset can be uploaded to the server and/or may be used locally. Additionally in some embodiments, the client may mark batches of images for offset adjustment.  
         [0034]     Some embodiments of the present invention allow users to reconcile the clock differences on their digital capture devices with the correct time on a server using preexisting technology. Some embodiments of the present invention allow batch correction of image time, thereby reducing the possibility for human error by automating the collection and computation of the offset, and greatly simplifying a rather tedious and complex task of correcting the time of past and present pictures.  
         [0035]     Fortunately, the internal clock of a typical media capture device provides timestamps that reflect relative time among captured content with sufficient accuracy. For example, if a camera&#39;s internal clock provides timestamps indicating a second photo was taken an hour after a first photo and a system can access an external reference time indicating when the first photo was taken, the system can determine the absolute time the second photo was taken by the camera. Furthermore, this process provides an absolute time any photo, taken either before or after the first photo, was captured.  
         [0036]     A system or method according to some embodiments of the present invention automatically or semi-automatically adjusts timestamps of multiple captured media content (such as photos, audio clips, videos or combinations thereof) captured from a single media capture device (such as a camera, audio recorder, video recorder, multi-function devices, or the like). Furthermore, a system or method according to other embodiments of the present invention provides accurate synchronization among multiple media capture devices. According to embodiments of the present invention, a user captures content that has a reference timestamp imbedded within the content. The media capture device associates a timestamp provided by its internal clock to the captured content. Thus, the captured content provides a fixed association between the reference time and the internal clock.  
         [0037]     For example, a user may use a digital camera to take a digital photo of a computer screen displaying a reference time. The digital camera tags the captured photo with a timestamp derived from its internal clock. Thus, by extracting the timestamp and the captured reference time, the captured photo may be used to correlate the camera&#39;s time with the external reference time. The correlation may be used to set an adjusted time for other photos taken before and after this reference photo. The correlation process is a direct result from a user taking a photo of a reference time, thus associating the camera&#39;s time with an external reference time.  
         [0038]     Some embodiments of the present invention assist in synchronizing time among content from multiple media content devices. In many cases, users are unable or unwilling to set the clock correctly on their media capture devices such as digital camera. Inaccurate clocks result in media content having incorrect timestamps. When these images are uploaded and posted to a server to be shared or viewed by others, the displayed time is incorrect making searching, browsing and sharing of images troublesome. In some cases, the number of media content with incorrect times is quite large, therefore making changing the displayed times manually tedious.  
         [0039]     Several methods may be used to provide an accurate timestamp for media content. A user may manually adjust the internal clock of a media capture device. A user may use a processing system to correlate media content with a reference time. The reference time is provided externally from the media capture device and may be presented to the media capture device visually and/or audibly, as well as encoded or unencoded. The processing system may be incorporated within the media capture device, may be external to the media capture device, or may be a combination of internal and external incorporation. Sections of the processing system that are external to the media capture device may reside on one or more systems such as completely within or partially within a user&#39;s home computer and/or one or more networked servers. The processing system may reside entirely with a user&#39;s home computer. Alternatively, the processing system may reside completely remote from the user, such as on a remote media server.  
         [0040]      FIG. 1  shows an exemplary system for time synchronization of media content, in accordance with some embodiments of the present invention. A reference time generator  10 , external to a media capture device  40 , provides a reference time  15 . This reference time  15  may be updated and provided periodically (e.g., every second or every fixed number of seconds). The reference time generator  10 , though external to the media capture device  40 , may be internal or external to a processing system  100 , which is further described below.  
         [0041]     An optional reference time encoder  20  may be used to encode the reference time  15  in a medium that may be captured by a media capture device  40 . For a media capture device  40  that captures audio, the reference time encoder  20  may encode the reference time  15  as a sequence of audible tones (e.g., DTMF tones,  300  baud modem tones or the like). For a media capture device  40  that captures images or video, the reference time encoder  15  may encode the reference time  15  as a one-dimensional (1-D) barcode, a two-dimensional (2-D) barcode (e.g., see  FIG. 4  described below) or the like. Alternatively, the reference time  15  may be presented in a human understandable form such as an audible reading of the reference time or a visual presentation via a clock or common Arabic numerals and punctuation.  
         [0042]     A presentation device, such as a display  20  of a computer or audio player (not shown), may be used to present a representation  32  of the reference time  15 . For example, a user&#39;s home computer may be used to access and display on its display  20  a 2-D barcode containing an encoded reference time. An applet running on the home computer may periodically update the presented representation of the reference time. In some embodiments, a web browser and/or an applet local to a user&#39;s computer receive and present an already encode reference time. In some embodiments, a web browser and/or an applet local to a user&#39;s computer receive an unencoded reference time and locally encode the reference time for presentation. In some embodiments, web browser and/or an applet present both encoded and unencoded representations concurrently  
         [0043]     A media capture device  40  includes an internal device clock  42 . This device clock  42  provides a time or timestamp that is separate and distinct from the reference time  15  provided reference time generator  10 . It may happen that the two times are identical, however, it is more probable that the device time is either unset or has some positive or negative offset from the reference time. According to embodiments of the present invention, this offset may be determined on a case-by-case basis.  
         [0044]     The media capture device  40  further includes a memory to hold captured media content  44 . Shown as first media content  44 A, the media capture device  40  associates a timestamp  46 A, which represents the time the content was captured, with captured content, such as a captured image  48 A. This timestamp  46 A is produced from the media capture device&#39;s internal clock  42  and is associated with the captured content such as being part of a header of a file containing the captured content.  
         [0045]     In the example shown, the captured image  48 A includes an image  35  from display  30 . According to embodiments of this invention, the media content  44 A may be processed to find a time relationship between reference times  15  produced by the reference time generator  15  and the device clock  42 . The example shows a second media content  44 B containing a second timestamp  46 B and a second captured image  48 B. The timestamp  46 B indicates time that the captured image  48 B was taken. The captured image  48 B may be any image a user would typically take when using a camera. There may also be many more additional such captured images.  
         [0046]     The media capture device  40  further includes a processor (not shown). The processor may be a general purpose processor, an application specific integrated circuit, an array of logic gates and/or the like. The processor may include functional code and/or hardware to perform various media capture device specific tasks.  
         [0047]     The media capture device  40  provides media content  50  to a processing system  100 . The processing system  100  may be fully internal to the media capture device  40 , fully external from media capture device  40 , or a partially internal to the media capture device  40 .  
         [0048]     The processing system  100  includes storage  110  to hold media content  44  with or without the timestamp  46 . That is, the timestamp  46  may be stored in separate memory. The storage  110  may include a single hard drive, an array of redundant hard drives, a network of short-term or long-term, persistent or non-persistent memory. The storage  110  may be internal and/or external to the media capture device  40 . The storage  110  may be local to a user&#39;s client computer, such as in a home personal computer, or may be part of a remote server.  
         [0049]     The processing system  100  further includes a processor  120 . If the processor  120  is internal to the media capture device  40 , processor  120  and the media capture device  40  processor (not shown) discussed above may be the same processor. Again, the processor  120  may be a general purpose processor, an application specific integrated circuit, an array of logic gates and/or the like. Furthermore, the processor  120  may be part of a server or a network of servers. The processor  120  may be a single processor or an arraignment of multiple associated processors. The processor  120  may include functional code and/or hardware to perform various media processing and manipulation functions.  
         [0050]     The media capture device  40  may provide the media content  50  directly to storage or the media content  50  may pass through the processor  120  first. The processor  120  includes a reference time decoder  122 , which may be code and/or hardware and may be one or more tasks, threads, procedures, processes and/or the like.  
         [0051]     The reference time decoder  122  reconstructs a reference time  15  by extracting the reference time  15  from media content  50  containing the representation  22  of the reference time. The decoder  122  may perform optical character recognition (OCR), voice recognition (VR), 1-D barcode decoding, 2-D barcode decoding, DTMF or modem decoding and/or the like.  
         [0052]     The processor  120  also extracts the timestamp  46  from the media content  44 . In some embodiments, the timestamp  46  is extracted from a header file in which the media content  44  is provided. In some embodiments, the timestamp  46  is extracted from a file&#39;s creation or modification time. In other embodiments in which the media content  44  contains an integrated timestamp  46  within the captured content  48 , the processor  120  extracted from the timestamp  46  from the captured content  48 . For example, if a photo contains an Arabic representation of the captured time and date, the processor may use OCR to extract the timestamp  46 .  
         [0053]     The processing system  100  further includes a memory  130 . The memory  130 , which may be collocated with the storage  110  or processor  120  and may be centralized to a single location or may be spread to disparate points on a network, contains memory to hold the decoded reference time  132  and the extracted timestamp  134 . The memory  130  may further contain memory to hold a relative offset or temporal difference  136  between the decoded reference time  132  and the extracted timestamp  134 .  
         [0054]     The time difference  136  may be used to set an adjusted time associated with a single media content or one or more groupings of media content. For example, one or more parameters configurable by a user and/or a system defined parameter may be used to set an adjusted time to accurately represent the time of collection. A parameter may be used to trigger the setting of an adjusted time for all media content associated with a particular upload event. Furthermore, one or more parameters may be used to trigger the setting of an adjusted time for all media content collected before a particular time, collected after a particular time, collected in a particulate day, week or month, or collected within a particular duration. One or more parameters may be used to trigger the setting of an adjusted time for all media content uploaded before a particular time, uploaded after a particular time, uploaded in a particulate day, week or month, or uploaded within a particular duration.  
         [0055]      FIGS. 2A through 2E  presents user and system process flows, in accordance with some embodiments of the present invention.  FIG. 2A  shows a process of a user capturing content. At  200 , a user captures media content using a media capture device  40 , such as a camera, phone or video camera. At  202 , the media capture device  40  associates current device time with captured media content. For example, the media capture device  40  places the capture time as a timestamp  46  in a header or as file creation date of media content file. At  204 , a user exports captured media content  44  to a processing system  100 , such as a local client PC or remote media server.  
         [0056]     In  FIG. 2B , a system provides a representation  22  of a reference time  15  for a user to capture. At  300 , a reference time generator  10 , such as a client PC or server, provides a reference time  15 . This reference time may be combined date and a universal coordinated time (derived from a source such as UTC time, GMT time, a government maintained standard time, or the like) or may be a local time with or without an indication of a time zone. At  302 , a reference time encoder  20 , which may be a function performed by a client PC or server, generates a representation  32  of the reference time  15 . For example, the representation  32  may be presented as a pixilated 1-D bar code, 2-D bar code or human readable text. At  304 , a presentation device such as a monitor  30  provides the representation  32  of reference time  15 , for example, as a pixilated image on a web page.  
         [0057]     In  FIG. 2C , a user captures media content  44 A that contains the representations  22  and may later be used for time adjustment operations. At  206 , a user captures an image  35  of representation  32  of the reference time using the media capture device  40 . At  208 , the media capture device  40  associates current device time from the device clock  42  with captured image  48 A as a timestamp  46 A. At  210 , the user exports a captured content  44 A including the captured image  48 A, such as in a media content file  50  including the representation  32  of the reference time  15  and the associated device timestamp  46 A. The user exports the media content file  50  to a processing system  100 . Concurrently, previously and/or subsequently, the user may export other media content  44 , such as media content  44 B, to the processing system  100 .  
         [0058]     Optionally in  FIG. 2D , a user selectively determine which uploaded media content will be time adjusted. At  212 , a user makes a selection of which media content to set an adjusted content time. For example, a user may be presented with one or more options to select such as all or any media content, media content matching criteria such as from particular exports or exported within temporal limits. At  214 , a user communicates the one or more selection parameters to the processing system  100 . For example, a user may have predefined configuration parameters, after-defined configuration parameters, or may identify specific media content. Alternatively, such parameters may be configurable by a system administrator or may me hard coded into executable software.  
         [0059]     In  FIG. 2E , the processing system  100  manipulates media content. At  306 , the processing system  100  receives the captured media content  50 , such as an image file, including the content  48 A including the representation  32  of the reference time  15  as well as the associated device time, such as timestamp  46 A, from capture device  40 . At  308 , the processing system  100  decodes the reference time  15  as a reconstructed reference time  132  from captured content  50 . In some embodiments, the processing system  100  self-determines whether or not captured content  50  contains a representation  32  of the reference time  32 . In other embodiments, a user indicates or tags a particular media content  50  as a reference media content for the processing system  100  to decode.  
         [0060]     Continuing at  310 , the processing system  100  extracts a device time  46 A as timestamp  134  from the captured media content  50 . Optionally at  312 , the processing system  100  obtains user selection parameter(s). The processing system  100  may use the reconstructed reference time  132  and the extracted time stamp  134  to adjust time for this and other associated media content. For example, the processing system  100  may compute an offset or a time difference  136 . Optionally at  314 , the processing system  100  sets an adjusted time, for example, based on user selection parameters and the time difference  136 .  
         [0061]     The actions performed as described above are not necessarily performed in the order presented. For example, a user may configure selection parameters before or after uploading content. An offset may be computed as each individual media content is uploaded or may compute offsets after multiple media content is uploaded. Furthermore, the processing system may decode the reference time either before or after it extracts the device timestamp. The order of executing other actions may also be interchanged, delayed and rearranged as those skilled in the art may determine.  
         [0062]      FIG. 3  presents another process flow, in accordance with some embodiments of the present invention. The exemplary system contains a media capture device  40  and a separate processing system  100  that includes a client PC and a media server  160 . At  400 , a user takes photograph(s) using a media capture device  40 , such as a digital camera.  
         [0063]     At  402 , using the client PC  150 , the user send request for display of an encoded reference time. At  404 , the media server  160  receives the request for reference time. At  406 , the media server  160  may periodically encoded a reference time as 2-D bar representation. At  408 , the media server  160  may periodically send an updated representation of reference time to the client PC  150 . At  410 , the client PC  150  receives and display an image containing the representation of reference time. At  412 , the user takes photograph of the displayed image.  
         [0064]     At  414  and  416 , the user uploads photographs from media capture device  40  to media server  160  using client PC  150 . At  418 , the media server  160  receives the photographs sent by the media capture device. At  420 , the media server  160  determines that a photograph contains a representation of a reference time.  
         [0065]     At  422 , the media server  160  extracts the reference time and the device timestamp and optionally computes their difference  136 . The media server  160  may further set adjusted time for one or more of the uploaded media content base on the difference  136  and optional configuration parameters.  
         [0066]      FIG. 4  illustrates an example screenshot showing an encoded 2-dimensional (2-D) barcode representation of a reference time, in accordance with some embodiments of the present invention. The screen shot presented on a display  30  may be a web page. The web page also includes an textual representation of the reference time  15 , an encoded 2-dimensional (2-D) barcode representation  32  of a reference time.  
         [0067]      FIG. 5  illustrates an example image captured by a media capture device, for example, of the screenshot of  FIG. 4 , in accordance with some embodiments of the present invention. The captured image  48 A is shown to include an integrated device timestamp at  46 A. Alternatively, the device timestamp may be stored separately in a header associated with the captured image as described below. The particular example shows a media content device that has a clock that is not calibrate or set properly. The device clock simply shows the duration of time since the device was first powered up. Embodiments of the present invention may accurately determine a time relative to an external clock or reference time as described above.  
         [0068]      FIG. 6  shows information associated with a captured image, in accordance with some embodiments of the present invention. In the example header, one or more parameters may be included. For example, the header file may include a creation time, a last-access time, and/or a last modified time. The processing system may include rules to select as the extracted time stamp, the creation time if available. If not available, a rule may be to selected a last-access time, and so on.  
         [0069]      FIG. 7  shows information associated with a processed image, in accordance with some embodiments of the present invention. The processing system may assemble additional information and associated with header information. For example, the processing system may store in memory the timestamp (shown as a captured image time in GMT format), the reference time (shown as a time from an EXIF header) and a local time (shown as local time from barcode image).  
         [0070]     Furthermore, the representation of the reference time may be encoded with additional information. For example, a 2-D bar code may contain a user identifier, a serial number, user preferences, access levels, location identifiers and/or the like. A processing system may further determine a time zone of the user by one of multiple means. For example, the processing system may determine the time zone from a camera property, from a user defined parameter that the user configures into the system, from information in the media content such as longitude/latitude GPS location information stored by the media capture device in the file header, from information extracted from the user&#39;s client computer, from the client&#39;s PC&#39;s Internet IP address, from the user&#39;s past actions and/or the like.  
         [0071]     While the invention has been described in terms of particular embodiments and illustrative figures, those of ordinary skill in the art will recognize that the invention is not limited to the embodiments or figures described. For example, many of the embodiments described above provide for presentation or collection of a reference time as a still image. In other embodiments, a audio or moving video presentation of a reference time may be provided.  
         [0072]     The figures provided are merely representational and may not be drawn to scale. Certain proportions thereof may be exaggerated, while others may be minimized. The figures are intended to illustrate various implementations of the invention that can be understood and appropriately carried out by those of ordinary skill in the art. Therefore, it should be understood that the invention can be practiced with modification and alteration within the spirit and scope of the appended claims. The description is not intended to be exhaustive or to limit the invention to the precise form disclosed. It should be understood that the invention can be practiced with modification and alteration and that the invention be limited only by the claims and the equivalents thereof.