CROSS-REFERENCE TO RELATED APPLICATIONSThis application is a continuation of U.S. utility application having Ser. No. 10/143,647, filed on May 10, 2002, which claims priority to copending U.S. provisional application having Ser. No. 60/290,315, filed on May 11, 2001, both of which are entirely incorporated herein by reference. Furthermore, this application is related to copending U.S. utility patent application entitled, “CHANNEL BUFFERING AND DISPLAY MANAGEMENT SYSTEM FOR MULTI-TUNER SET-TOP BOX”, which is referenced under Scientific Atlanta docket number 7315 and has issued under U.S. Pat. No. 7,409,140 on Aug. 5, 2008, for which the inventors are Arturo Rodriguez and Ramesh Nallur, which is filed on even date herewith, and which is entirely incorporated herein by reference.
TECHNICAL FIELDThe invention is generally related to television systems, and, more particularly, is related to buffering video presentations.
BACKGROUND OF THE INVENTIONSubscriber television systems are now capable of providing many services in addition to analog broadcast video. In implementing enhanced programming, the home communication terminal (“HCT”), otherwise known as the settop box, has become an important computing device for accessing various video services. In addition to supporting traditional analog broadcast video functionality, digital HCTs (or “DHCTs”) now also support an increasing number of two-way digital services such as video-on-demand.
A DHCT is typically connected to a cable or satellite television network and includes hardware and software for providing various services and functionality. In some systems, software executed by a DHCT can be downloaded and/or updated via the subscriber television network. The ability to download software provides flexibility in adding or updating applications executed by the DHCT. Each DHCT also typically includes a processor, communication components and memory, and is connected to a television. While many conventional DHCTs are stand-alone devices that are externally connected to a television, a DHCT and/or its functionality may be integrated into a television or other display device, as will be appreciated by those of ordinary skill in the art.
Some DHCTs include mechanisms for buffering a video presentation, including while it is being presented to a viewer. This buffering functionality allows a viewer to manipulate the video presentation using trick mode operations such as rewind, fast-forward, pause, and play. One problem with buffering functionality offered by current DHCTs is that the buffering capacity is fixed. When a viewer is presented with video presentations comprising data that exceeds the fixed buffering capacity, a portion of the previously buffered data is erased or over-written in order to accommodate the buffering of new data. For some users, the buffering capacity offered by a DHCT is more than satisfactory. However, other users may desire additional buffering capacity. For example, viewers that typically watch longer video presentations (e.g., 3 hour movies) may have a greater need for a larger buffer capacity than viewers that typically watch shorter video presentations (e.g., 30 minute sit-coms). Another problem with buffering functionality offered by DHCTs is that viewers may have different preferences regarding buffered video presentations. For example, viewers may have different preferences regarding whether buffered video presentations corresponding to previously displayed television channels should continue to be accessible after a change in television channels. Based on the foregoing, there exists a need for systems and methods that address these and/or other problems associated with buffering video presentations.
BRIEF DESCRIPTION OF THE DRAWINGSEmbodiments of the invention can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, emphasis instead being placed upon clearly illustrating the principles of the invention. In the drawings, like reference numerals designate corresponding parts throughout the several views.
FIG. 1 is a high-level block diagram depicting an example of a subscriber television system.
FIG. 2 is a block diagram illustrating an example of selected components of the DHCT depicted inFIG. 1 in accordance with one embodiment of the invention.
FIG. 3 is a block diagram illustrating an example of selected content of the system memory of the DHCT depicted inFIG. 2.
FIG. 4 is a block diagram illustrating an example of a remote control that may be used to provide user input to the DHCT depicted inFIG. 2.
FIG. 5 is a flow chart illustrating an example of a method for managing the buffering capacity of the DHCT depicted inFIG. 1.
FIG. 6 is a flow chart illustrating an example of a method for managing buffering functionality of the DHCT depicted inFIG. 1.
FIG. 7 is a flow chart illustrating an example of a method for recording a buffered video presentation by the DHCT depicted inFIG. 1.
FIG. 8 is a block diagram illustrating an example of a user interface (UI) screen that includes a list of television programs recorded by the DHCT depicted in FIG.
FIG. 9 is a block diagram illustrating an example of a UI screen that includes a list of recording and buffering options provided by the DHCT depicted inFIG. 1.
FIG. 10 is a block diagram illustrating an example of a UI screen that includes a list of buffer management options provided by the DHCT depicted inFIG. 1.
FIG. 11 is a block diagram illustrating an example of a UI screen that includes a list of buffer size options provided by the DHCT depicted inFIG. 1.
FIG. 12A is a block diagram illustrating an example of a UI screen that includes a list of inter-channel buffering options provided by the DHCT depicted inFIG. 1.
FIG. 12B is a block diagram illustrating another example of a UI screen that includes a list of inter-channel buffering options provided by the DHCT depicted inFIG. 1.
FIG. 13A is a block diagram illustrating an example of a UI screen that includes a list of video presentations that are buffered by the DHCT depicted inFIG. 1.
FIG. 13B is a block diagram illustrating an example of another UI screen that includes a list of video presentations that are buffered by the DHCT depicted inFIG. 1.
FIG. 14 is a block diagram illustrating an example of a UI screen that includes options for sorting a list video presentations that are buffered by the DHCT depicted inFIG. 1.
FIGS. 15A,15B, and15C depict non-limiting examples of Sorted Buffered Programs List screens that may be requested by selecting respective options from the UI screen depicted inFIG. 14.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTSThe preferred embodiments of the invention now will be described more fully hereinafter with reference to the accompanying drawings. In particular, preferred embodiments of managing time-shift buffers (TSBs) will be described. A TSB comprises storage media that is used for buffering audio and/or video (A/V) data. The buffering of A/V data allows a user of a digital home communication terminal (DHCT) to perform trick mode operations on a television presentation that is currently being broadcast. Such trick mode operations may include pause, fast-rewind, fast-forward, slow-reverse, slow-forward, and/or play. In one embodiment of the invention, a user is provided with systems for managing one or more TSBs. Where more than one TSB is used in a DHCT, each TSB typically buffers A/V data that is output by a respective tuner. In one embodiment, a TSB may buffer A/V data that is received by the DHCT from a consumer electronics device such as, for example, a camcorder. The consumer electronics device may be connected to the DHCT via a wired or wireless port. In the description that follows,FIGS. 1-4 will provide an example of system components that may be used to help implement and/or manage a TSB. Furthermore, examples of methods for managing TSBs are illustrated in the flow charts ofFIGS. 5-7. Finally, user interface (UI) screens that may be provided in connection with managing a TSB are illustrated inFIGS. 8-15. Note, however, that the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Furthermore, all examples given herein are intended to be non-limiting, and are provided in order to help convey the scope of the invention.
FIG. 1 is a block diagram depicting a non-limiting example of a subscriber television system (STS)100 in accordance with one embodiment of the invention. In this example, theSTS100 includes aheadend110 and aDHCT200 that are coupled via anetwork130. TheDHCT200 is typically situated at a user's residence or place of business and may be a stand-alone unit or integrated into another device such as, for example, thedisplay device140. TheDHCT200 receives signals (video, audio and/or other data) including, for example, MPEG-2 streams, among others, from theheadend110 through thenetwork130 and provides any reverse information to theheadend110 through thenetwork130. Thenetwork130 may be any suitable means for communicating television services data including, for example, a cable television network or a satellite television network, among others. Theheadend110 may include one or more server devices (not shown) for providing video, audio, and textual data to client devices such as theDHCT200. Theheadend110 and theDHCT200 cooperate to provide a user with television functionality including, for example, television programs, an interactive program guide (IPG), and/or video-on-demand (VOD) presentations. The television services are provided via thedisplay device140. Thedisplay device140 may be a television or any other device capable of displaying video images and/or playing any corresponding audio.
FIG. 2 is a block diagram illustrating selected components of aDHCT200 in accordance with one embodiment of the invention. TheDHCT200 depicted inFIG. 2 is merely illustrative and should not be construed as implying any limitations upon the scope of the preferred embodiments of the invention. For example, in another embodiment, a DHCT may have fewer, additional, and/or different components than illustrated inFIG. 2. TheDHCT200 preferably includes acommunications interface242 for receiving signals (video, audio and/or other data) from theheadend110 through the network130 (FIG. 1) and for providing any reverse information to theheadend110.
TheDHCT200 further preferably includes at least oneprocessor244 for controlling operations of theDHCT200, anoutput system248 for driving thedisplay device140, and atuner system245 for tuning to a particular television channel or frequency and for sending and receiving various types of data to/from theheadend110. In one embodiment, theoutput system248 may be part of themedia engine222.Tuner system245 can select from a plurality of transmission signals provided by thesubscriber television system100.Tuner system245 enables theDHCT200 to tune to downstream media and data transmissions, thereby allowing a user to receive digital or analog media content via the subscriber television system. Thetuner system245 includes, in one implementation, an out-of-band tuner for bi-directional quadrature phase shift keying (QPSK) data communication and a quadrature amplitude modulation (QAM) tuner (in band) for receiving television signals. In one embodiment, thetuner system245 includes a plurality of tuners for receiving a plurality of video streams.
TheDHCT200 may include one or more wireless orwired communication ports274 for receiving and/or transmitting data to other devices. Thecommunication ports274 may include a USB (Universal Serial Bus), an Ethernet, an IEEE-1394 bus, an analog video input port, a serial port, and/or a parallel port, among others. In one embodiment, theDHCT200 may receive A/V data from a consumer electronics device such as, for example, a camcorder, via one of thecommunication ports274. TheDHCT200 may also include areceiver246 for receiving externally-generated user inputs or commands from an input device such as, for example, a remote control.
TheDHCT200 includes at least onestorage device273 for storing video streams received by theDHCT200. APVR application277, in cooperation with theoperating system253 and thedevice driver211, effects, among other functions, read and/or write operations to thestorage device273. Note that, references herein to write and/or read operations to/from thestorage device273, or portions thereof, will be understood to mean that such operations are performed to/from the storage medium or media (e.g., hard disks) of thestorage device273, unless indicated otherwise. Thedevice driver211 is a software module that preferably resides in theoperating system253. Thedevice driver211, under management of theoperating system253, provides operating instructions to thestorage device273. Thecontroller279 of thestorage device273 receives operating instructions from thedevice driver211 and implements those instructions to cause read and/or write operations to a hard disk201 (i.e., hard disk201-1 or hard disk201-2). Furthermore, thedevice driver211, in cooperation with theoperating system253, communicates with thestorage device controller279 to format and/or manipulate a hard disk201.
Thestorage device273 is preferably coupled to acommon bus205 through acommunication interface275. Thecommunication interface275 is preferably an integrated drive electronics (IDE) interface or a small computer system interface (SCSI), although another interface such as, for example, IEEE-1394 or USB, among others, may be used. Alternatively, thestorage device273 can be externally connected to theDHCT200 via acommunication port274. Thecommunication port274 may be, for example, an IEEE-1394, a USB, a SCSI, or an IDE, among others.
In one implementation, video streams are received inDHCT200 viacommunications interface242 and stored in a temporary memory cache. The temporary memory cache may be a designated section ofDRAM252 or an independent memory attached directly tocommunication interface242. The temporary cache is implemented and managed to enable media content transfers tostorage device273. In one implementation, the fast access time and high data transfer rate characteristics of thestorage device273 enable media content to be read from the temporary cache and written tostorage device273 in a sufficiently fast manner. Multiple simultaneous data transfer operations may be implemented so that while data is being transferred from the temporary cache tostorage device273, additional data may be received and stored in the temporary cache.
Thestorage device273 preferably includes a hard disk drive but may, in an alternative embodiment, include any type of storage medium, such as, for example, a magnetic, optical, or semiconductor based storage medium, among others. Thestorage device273 preferably includes at least two hard disks201-1 and201-2 that include storage capacity corresponding to respective buffers TSB204-1 and TSB204-2. In an alternative embodiment, TSB204-1 and TSB204-2 may be included on a single hard disk. In another embodiment, a TSB204 (i.e., TSB204-1 or TSB204-2) may reside in more than one storage medium. In yet another embodiment, a TSB204 may reside in a storage medium that is not a hard disk.
In one embodiment of the invention, theoperating system253,device driver211, andcontroller279 cooperate to create a file allocation table (FAT). The FAT is where theoperating system253 stores information about hard disk clusters and the files associated with those clusters. Theoperating system253 can determine where a file's data is located by using FAT entries. A FAT entry describes the physical locations of data for a video stream file (i.e., a file that the video stream is written to on a hard disk201). The FAT also keeps track of which clusters are free, or open, and thus available for use. To buffer a downloaded video stream into thestorage device273, thePVR application277, in one preferred embodiment, creates a file and file name for the video stream to be downloaded. Theoperating system253, in cooperation with thedevice driver211, checks the FAT for an available, or writable, cluster for storing the video stream.
When an application such asPVR application277 creates (or extends) a video stream file, theoperating system253, in cooperation with thedevice driver211, queries the FAT for an available cluster to begin writing the video stream. The PVR application277 (through communication with theoperating system253 and/or device driver211) causes thecontroller279 to write a downloaded video stream to the available cluster under a particular video stream file name. The FAT is then updated with the new video stream file name corresponding to the available cluster. If the video stream requires more storage space than what the cluster can offer, theoperating system253 queries the FAT for the location of another available cluster to continue writing the video stream. The FAT is updated to keep track of which clusters store a particular video stream under the given video stream file name.
A multiplicity of clusters may be required to write a file corresponding to a compressed video stream to a hard disk201. The clusters corresponding to one particular video stream file may or may not be adjacent or contiguous in the hard disk201. The clusters corresponding to a particular video stream file can be fragmented throughout a hard disk storage space. As described earlier, a file allocation table (FAT) keeps track of which clusters are employed to write a downloaded video stream to a hard disk201. A defragmentation operation may be used by thedevice driver211 to cause the clusters associated with a particular video stream file to be contiguous. Other preferred embodiments include other file allocation mechanism for storing data according to the functions described herein.
TheDHCT200 preferably comprises asignal processing system214 which includes ademodulating system213 and a transport demultiplexing and parsing system215 (herein referred to as demultiplexing system215). The components ofsignal processing system214 are preferably capable of QAM demodulation, forward error correction, demultiplexing MPEG-2 transport streams, and parsing elementary streams. One or more of the components of thesignal processing system214 can be implemented with software, a combination of software and hardware, or preferably in hardware.
Thedemodulating system213 comprises functionality for demodulating analog or digital transmission signals. For instance,demodulating system213 can demodulate a digital transmission signal in a carrier frequency that was modulated, among others, as a QAM-modulated signal. When tuned to a carrier frequency corresponding to an analog TV signal,demultiplexing system215 is bypassed and the demodulated analog TV signal that is output by demodulatingsystem213 is instead forwarded toanalog video decoder216.Analog video decoder216 converts the analog TV signal into a sequence of digitized pictures and their respective digitized audio. The digitized pictures and respective audio that are output byanalog video decoder216 are forwarded to thecompression engine217.
Thecompression engine217 processes the sequence of digitized pictures and digitized audio and converts them into compressed video and audio streams, respectively. The compressed video and audio streams are produced in accordance with the syntax and semantics of a designated audio and video coding method, such as, for example, MPEG-2, so that they can be interpreted byvideo decoder223 andaudio decoder225 for decompression and reconstruction at a future time. Each compressed stream consists of a sequence of data packets containing a header and a payload. Each header contains a unique packet identification code, or PID, associated with the respective compressed stream.
Thecompression engine217 multiplexes the audio and video compressed streams into a transport stream, such as, for example, an MPEG-2 transport stream. Furthermore, thecompression engine217 can compress audio and video data corresponding to multiple video streams in parallel (e.g., multiple analog TV signals received by multiple tuners) and can multiplex the respective audio and video compressed streams into a single transport stream. Thecompression engine217 may use a dedicated local memory module (not shown) for storing data before, during, and/or after processing by thecompression engine217. The compressed streams output bycompression engine217 are provided as input to signalprocessing system214.
Thedemultiplexing system215 of thesignal processing system214 interprets sequence and picture headers and annotates their locations within their respective compressed stream. Annotating the location of sequence and picture headers facilitates the implementation of trick mode operations on a compressed stream. An analog video stream (e.g., corresponding to a TV presentation) that is received via a tuned analog transmission channel can be output as a transport stream bysignal processing system214 and stored instorage device273. A compressed stream may be also output bysignal processing system214 and presented as input tomedia engine222. Thevideo decoder223 and theaudio decoder225 of themedia engine222 can decompress the compressed stream for subsequent output to the display device140 (FIG. 1).
Thedemultiplexing system215 may include means for MPEG-2 transport demultiplexing. When tuned to carrier frequencies carrying a digital transmission signal,demultiplexing system215 extracts data packets corresponding to desired video streams for further processing. Therefore, thedemultiplexing system215 may preclude further processing of data packets corresponding to unwanted video streams. Thedemultiplexing system215 parses (i.e., reads and interprets) desired video streams to interpret sequence headers and picture headers, and deposits the video streams intoDRAM252. Theprocessor244 then causes the video streams to be transferred fromDRAM252 to thestorage device273.
A compressed video stream corresponding to a tuned carrier frequency carrying a digital transmission signal can be output as a transport stream bysignal processing system214 and stored instorage device273. A packetized compressed stream can also be output bysignal processing system214 and presented as input tomedia engine222. Thevideo decoder223 and/oraudio decoder223 of themedia engine222 may decompress the compressed stream for subsequent output to thedisplay device140.
One having ordinary skill in the art will appreciate thatsignal processing system214 may include other components not shown, including memory, decryptors, samplers, digitizers (e.g., analog-to-digital converters), and multiplexers, among others. Further, other embodiments will be understood, by those having ordinary skill in the art, to be within the scope of the preferred embodiments of the invention. For example, analog signals (e.g., NTSC) may bypass one or more elements of thesignal processing system214 and may be forwarded directly to theoutput system248. In addition, data that is output by one DHCT component (e.g., signal processing system214) may be temporarily stored inDRAM252 prior to being received as input by another DHCT component (e.g.,media engine222 or analog video decoder216). It will also be understood by those having ordinary skill in the art that components ofsignal processing system214 can be located in different areas of theDHCT200.
In one embodiment of the invention, a plurality of tuners andrespective demodulating systems213,demultiplexing systems215, andsignal processing systems214 may simultaneously receive and process a plurality of respective broadcast digital video streams. Alternatively, asingle demodulating system213, asingle demultiplexing system215, and a singlesignal processing system214, each with sufficient processing capabilities may be used to process a plurality of digital video streams that are received by a plurality of respective tuners.
In yet another embodiment, a first tuner intuning system245 receives an analog video signal corresponding to a first video stream and a second tuner simultaneously receives a digital compressed stream corresponding to a second video stream. The first video stream is converted into a digital format. The second video stream (or a compressed digital version thereof) is forwarded to thestorage device273 for storage on a hard disk201. Data annotations for each of the two streams are performed to facilitate future retrieval of the video streams from thestorage device273. The first video stream and/or the second video stream may also be forwarded tomedia engine222 for decoding and subsequent presentation via display device140 (FIG. 1).
A plurality ofcompression engines217 may also be used to simultaneously compress a plurality of analog video streams. Alternatively, asingle compression engine217 with sufficient processing capabilities may be used to compress a plurality of analog video streams. Compressed digital versions of respective analog video streams may be forwarded to thestorage device273 for storage on a hard disk201. Data annotations for each of the video streams may be performed to facilitate future retrieval of the video streams from thestorage device273. Depending on requirements in effect, only a subset of compressed video streams may be forwarded to thestorage device273. Any of the received video streams may also be simultaneously forwarded tomedia engine222 for decoding and subsequent presentation via thedisplay device140.
FIG. 3 is a block diagram illustrating selected components stored in thesystem memory249 of the DHCT200 (FIG. 2), in accordance with one preferred embodiment. Thesystem memory249 described herein is merely illustrative and should not be construed as implying any limitations upon the scope of the invention. In one implementation,system memory249 includesflash memory251 and dynamic random access memory (DRAM)252 for storing various applications, modules and data for execution and use by theprocessor244. In an alternative embodiment,system memory249 may include additional, fewer, and/or different types of memory.
Basic functionality of theDHCT200 is provided by anoperating system253 that is primarily stored inflash memory251. Theoperating system253 includes at least oneresource manager350 that provides an interface to and coordination of resources of theDHCT200 such as, for example, computing resources. One or more software applications, herein referred to as applications, are executed by utilizing the computing resources in theDHCT200. Applications stored inflash memory251 orDRAM252 are executed byprocessor244 under the auspices of theoperating system253. Data required as input by an application is stored inDRAM252 orflash memory251 and read byprocessor244 as needed during the course of the application's execution. Input data may be data stored inDRAM252 by a secondary application or other source, either internal or external to theDHCT200. Data generated by an application is stored inDRAM252 byprocessor244 during the course of the application's execution.
An application referred to asnavigator360 is also resident inflash memory251 for providing a navigation framework for services provided by theDHCT200. Thenavigator360 registers for and in some cases reserves certain user inputs related to remote control keys such as channel up/down, last channel, favorite channel, etc. Aplatform library310 includes a collection of utilities useful to applications. Such utilities may include a timer manager, a compression manager, an HTML parser, a database manager, a widget toolkit, a string manager, and other utilities (not shown). These utilities are accessed by applications via application programming interfaces (APIs) as necessary so that each application does not have to incorporate these utilities. Two components of theplatform library310 that are depicted inFIG. 3 are awindow manager330 and a service application manager (SAM)client320.
Thewindow manager330 provides a mechanism for implementing the sharing of the screen regions and user input. Thewindow manager330 is also responsible for, as directed by one or more applications, implementing the creation, display, and allocation of thelimited DHCT200 screen resources. Thewindow manager330 allows multiple applications to share the screen by assigning ownership of screen regions. Thewindow manager330 communicates withresource manager350 to coordinate available resources (such as display memory) among different resource-consuming processes. Such processes may be directly or indirectly invoked by one or more applications.
Thewindow manager330 also maintains, among other things, auser input registry365 inDRAM252. Theuser input registry365 may be accessed to determine which of various applications running on theDHCT200 should receive data corresponding to a user input, and in which order. As an application is executed, it registers a request to receive certain user input keys or commands. When the user presses a key corresponding to one of the commands on the remote control device, the command is received by thereceiver246 and relayed to theprocessor244. Theprocessor244 dispatches the event to theoperating system253 where it is forwarded to thewindow manager330. Thewindow manager330 then accesses theuser input registry365 and routes data corresponding to the incoming command to the appropriate application.
TheSAM client320 is a client component of a client-server system, with the server component being located on the headend110 (FIG. 1). ASAM database322 inDRAM252 includes a data structure of services that are created and updated by theheadend110. Many television services can be defined using the same application component, with different parameters. Television services may include, without limitation and in accordance with one implementation, the presentation of television broadcast programs, video-on-demand (VOD), music, and/or an interactive program guide (IPG). In general, the identification of a service includes the identification of an executable application that provides the service along with a set of application-dependent parameters that indicate to the application the service to be provided. As a non-limiting example, a service of presenting a television program could be executed with a set of parameters to view HBO or with a separate set of parameters to view CNN. Each association of the application component (e.g., watchTV398) and one parameter component (HBO or CNN) represents a particular service that has a unique service I.D.
Applications can be downloaded intoDRAM252 at the request of theSAM client320, typically in response to a request by the user or in response to a message from the headend. In this non-limiting example,DRAM252 contains aPVR application277, an interactive program guide (IPG)application370, and a video-on-demand (VOD)application380. It should be clear to one with ordinary skill in the art that these applications are not limiting and merely serve as examples for this present embodiment of the invention. Furthermore, one ormore DRAM252 based applications may, as an alternative embodiment, be resident inflash memory251, or vice versa.
ThePVR application277 provides user interface (UI) screens that assist the user in buffering, recording, and viewing video presentations. For instance, thePVR application277 may be configured to provide the user with the UI screens depicted inFIGS. 8-15. As used herein, a video presentation may be a television presentation such as, for example, a movie, a television show, a cartoon, a news program, a sports program, or a series episode, among others. A video presentation may be received as a broadcast A/V signal or may be downloaded interactively via thetuner system245. A video signal may also be received via one of thecommunication ports274 from a consumer electronics device such as, for example, a camcorder, a VCR, or a DVD player. ThePVR application277 may be implemented in hardware, software, firmware, or a combination thereof.
In a preferred embodiment, thePVR application277 is implemented in software that is stored in aDRAM252 and that is executed byprocessor244. ThePVR application277, which may comprise an ordered listing of executable instructions for implementing logical functions, may be embodied in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, a processor-containing system, or another system that can fetch instructions from the instruction execution system, apparatus, or device and execute them.
ThePVR application277 provides for A/V data storage functionality by enabling the temporary writing to, and if requested, long-term recording to thestorage device273. Through mechanisms explained below, A/V data is buffered in a TSB204 (i.e., TSB204-1 or TSB204-2). In accordance with a preferred embodiment, thePVR application277 manages a TSB204 at the application level for each tuner and/or a local device providing A/V data. Hence, each tuner intuner system245 and/or local device attached to theDHCT200 may have a respective TSB204. Data that is buffered in a TSB204 may have been received from a remote server via the subscriber television network130 (FIG. 1), from a local device via a home communication network, or from a consumer device such as, for example, a video camera that is directly connected to theDHCT200.
The A/V data buffered in a TSB204 may be retained (in response to user input) as a long-term recording or may be deleted as additional A/V data is buffered. The A/V data buffered in a TSB204 may be deleted by, for example, deleting a TSB management file associated with the data and/or by designating the clusters storing the A/V data as writable (for eventual write operations that overwrite the A/V data within those clusters).
A long-term recording will be understood to comprise A/V data that is stored for an extended period of time as determined by the user. Long-term recordings are stored in clusters that are not assigned to a TSB204. A long-term recording may be scheduled in advance of its broadcast time or may be achieved by selecting a video presentation buffered in a TSB204 and designating it as a long-term recording. As will be described below, designating a video presentation as a long term recording can occur, in one implementation, by receiving user input selecting the video presentation from a list provided via a UI screen. ThePVR application277 responds by “flagging” the associated TSB management file as corresponding to a long-term recording. The designation of a video presentation as a long-term recording is relayed to thedevice driver211 which may effect the removal of the clusters containing the video presentation from a TSB204. In one embodiment, the removal of clusters containing the video presentation from a TSB204 may be implemented by associating the clusters with a file corresponding to the long-term recording, and by replenishing the TSB204 with an equal number of clusters from a pool of available clusters. A long-term recording may eventually be deleted from thestorage device273 in response to, for example, a user request. This deletion occurs, in one implementation, by configuring the associated non-buffer clusters as writable, and thus eventually available for the buffering or recording of other A/V data. In an alternative embodiment, a buffered video presentation that is designated as a long term recording may be copied from a TSB204 to another portion of a hard disk201 for long term storage.
In one implementation, applications executing on theDHCT200 work with thenavigator360 by abiding by several guidelines. First, an application utilizes theSAM client320 for the provision, activation, and suspension of services. Second, an application sharesDHCT200 resources with other applications and abides by the resource management policies of theSAM client320, theoperating system253, and theDHCT200. Third, an application conforms to situations where shared resources are only accessible via thenavigator360. Fourth, when an application loses service authorization while providing a service, the application suspends the service via theSAM client320. Thenavigator360 may reactivate an individual service application when it later becomes authorized. Finally, an application client is designed to not have access to commands corresponding to certain user input keys reserved by the navigator360 (e.g., power, channel +/−, volume +/−, etc.).
Data and software used in providing a DHCT service to a user may be stored in one or more of the following memory resources: a data storage device located at a headend, a data storage device located at a customer premises, a volatile or non-volatile memory internal to theDHCT200, and/or a hard drive internal to theDHCT200. For example, an executable program or algorithm corresponding to an operating system (OS) component, or to a client platform component, or to a client application (e.g., PVR application277), or to respective parts thereof, may reside in and/or execute out ofDRAM252 and/orflash memory251. An executable program or algorithm may also reside in astorage device273 and/or an external storage device and may be transferred intoDRAM252 for execution. Likewise, data input and/or output for an executable program or algorithm may be stored inDRAM252, inflash memory251, instorage device273, and/or in a storage device connected to theDHCT200.
FIG. 4 depicts a non-limiting example of a remote control device400 that may be used to provide user input to theDHCT200. The remote control device400 described herein is merely illustrative and should not be construed as implying any limitations upon the scope of the invention. Fourarrow keys410 are provided including an uparrow key411, adown arrow key412, aleft arrow key413, and aright arrow key414. Thearrow keys410 can be used to scroll through on-screen options and/or to highlight an on-screen option. Aselect key420 may be used to select a currently highlighted option.
The functions of an “A”key471, a “B” key472, and a “C” key473 may vary depending on the UI screen being presented to a user at the time of the key's activation. For instance, when the UI screen illustrated inFIG. 9 is presented to a user, the “C” key473 may be used to request a previously displayed UI screen. Other remote control keys may function as follows: a List key430 may be used to request a list of video recordings that are stored instorage device273; anInfo key432 may be used to request additional information regarding a video presentation; and video control keys421-426 may be used to control a VCR and/or to request PVR functionality such as play (421), fast-forward (422), rewind (423), stop (424), pause (425), and record (426).
FIG. 5 is a flow chart illustrating a method for managing the buffering capacity of the DHCT200 (FIG. 1). Instep501, theDHCT200 receives user input identifying a desired buffering capacity for a TSB204. As in other examples discussed below, a user input may be received via, for example, a remote control device, and may correspond to an option that is displayed via a UI screen. The desired buffering capacity is preferably identified in terms of the play-time of the buffered A/V data. For example, a user may be able to select a one-hour buffering capacity if the user desires the ability to access up to one hour of buffered video presentations. In another embodiment, the buffering capacity may be identified in terms of a number of data units (e.g., bytes) that may be buffered in a TSB204. In yet another embodiment, buffering capacities for more than one TSB204 may be identified by user input.
After the user identifies a desired buffering capacity for a TSB204, the amount of data that is buffered in a TSB204 is limited (as indicated in step502) such that it does not, or substantially does not, exceed the capacity that is identified by the user input. One approach for limiting the amount of data that is buffered in a TSB204 is to assign to the TSB a storage capacity (e.g., a certain number of clusters) that corresponds to the user selected buffering capacity. A buffering capacity that is identified in terms of a play-time may be implemented based on an estimated number of data units that typically provide such play-time. For example, if a user identifies a desired TSB capacity as one-hour, then the storage capacity that is assigned to a TSB204 may be limited to a predetermined number of bytes that is estimated to provide an average play-time of one-hour.
More than one approach may be used to manage a TSB204 after a certain storage capacity has been allocated to it. In one implementation, after the TSB is full of buffered data, then additional data being buffered in the TSB is written over previously buffered data. The previously buffered data that is over-written is preferably, but not necessarily, data that had been residing in the TSB for the longest duration as compared to other TSB content. In another implementation, after the TSB is full of buffered data, then a portion of the storage capacity allocated to the TSB is de-allocated from the TSB, and additional storage capacity that is equivalent to the de-allocated portion is assigned to the TSB to accommodate additional data buffering. The portion of storage capacity that is de-allocated from the TSB preferably, but not necessarily, contains data that had been residing in the TSB for the longest duration as compared to other TSB content.
ThePVR application277 may be used to help maintain a user defined storage capacity for a TSB204. In a preferred embodiment, the storage capacity of a TSB204 corresponds to a portion of a hard disk201. If storage capacity is defined based on a desired play time, then a corresponding data unit capacity (e.g., in terms of bytes) may be determined based on an estimated data rate. For example, if a user selects a TSB storage capacity corresponding to 3 hours of play time, then assuming a constant bit rate of 2 mega bits per second (Mbps), thePVR application277 may assign 0.9 gigabytes (GB) of storage capacity to the TSB204.
ThePVR application277 may track available disk space and use it to maintain the TSB storage capacity at a desired level. For example, before thePVR application277 effects a write operation to a TSB204, it can query the device driver211 (through the operating system253) to determine available hard disk space. After a write operation, thePVR application277 can again poll thedevice driver211 to get an update on available hard disk space.
A TSB204 preferably comprises a plurality of clusters. The total storage capacity of the TSB clusters, at any one time, may be less than or greater than the user-defined TSB storage capacity because of variations in the bit-rate within a video stream and between video streams that are stored in a TSB204. The variations, if any, of the amount of clusters in a TSB204 will preferably represent a small percentage of the TSB capacity, thereby resulting in a substantially constant TSB size over time.
ThePVR application277 preferably manages a TSB204 by creating a TSB management file associated with each buffered video presentation. A buffered video presentation may include an entire broadcast video presentation or only a portion thereof. For example, if the video presentation Friends is broadcast from 8:00 p.m. to 8:30 p.m., then the buffered video presentation of Friends may only include the portion that was broadcast between 8:15 and 8:30 p.m. ThePVR application277 determines at what time the video presentation was tuned based on a real-time clock value that is forwarded by theoperating system253. ThePVR application277 also receives program guide data from, for example, an IPG application370 (FIG. 3). The program guide data may include start and end times of each video presentation and may be received by theIPG application370 from theheadend110. ThePVR application277 may use the program guide data and the values from a real-time clock to create TSB management files for tracking respective buffered video presentations. The TSB management files may also be used to provide a UI screen that includes a list of video presentations currently stored in a TSB204. In one embodiment, a TSB management file, which may be stored inDRAM252, can include program guide data (e.g., title and broadcast time) as well as data representing the beginning and end time of buffered portions of video presentations.
FIG. 6 is a flow chart illustrating a method for managing buffering functionality of theDHCT200. Instep601, theDHCT200 receives user input identifying whether to enable access to buffered data corresponding to a TV channel that was displayed prior to a change in TV channels (i.e., whether to enable access to prior-channel buffered data). Then instep602, access to prior-channel buffered data is enabled or disabled accordingly.
When access to prior-channel buffered data is enabled, then a user may have access to buffered video presentations corresponding to two or more respective television channels that are displayed to the user as a result of one or more channel changes. In one implementation, a video presentation is only buffered and/or accessible if the corresponding television channel is presented to a user for more than a predetermined time period. In one embodiment, this predetermined time period may be specified by user input.
As a non-limiting example, assume that a user requests that access to prior-channel buffered data be enabled, and that the user subsequently watches the video presentation Friends onchannel11. Then, in such a scenario, after the user effects a change of the displayed television channel fromchannel11 to channel12, the user will still be able to review the portion of Friends that was displayed onchannel11 prior to the change to channel12. In other words, data that is buffered prior to a change in channels is not deleted or otherwise rendered inaccessible.
If a user requests that access to a prior-channel buffered data be disabled, then buffered video presentations corresponding to a prior channel are deleted and/or rendered inaccessible. A video presentation may be rendered inaccessible by, for example, deleting a corresponding TSB management file and/or by setting a flag that identifies the video presentation as inaccessible.
In another embodiment, a user may press a certain remote control key (e.g., thebuffer key436 or therecord key426,FIG. 4) within a short time interval (e.g., 2 seconds) prior to invoking a change in TV channels (e.g., via the channel +/−key434) in order to cause a TV channel being currently viewed to continue being buffered in a TSB204 after the change in TV channels is implemented. In this manner a user is provided with a quick method for activating inter-channel buffering. The activation of inter-channel buffering via a certain remote control key may be enabled or disabled by a user via an interactive configuration session (e.g., by selecting a corresponding option via a UI screen).
FIG. 7 is a flow chart illustrating a method for recording a buffered video presentation by the DHCT200 (FIG. 1). Instep701, theDHCT200 provides a user with a list of buffered video presentations. Each buffered video presentation may correspond to either an entire video presentation (e.g., a movie, a show, a cartoon, a series episode, etc.) or a portion thereof. Instep702, theDHCT200 receives user input identifying a buffered video presentation that is to be stored as a long-term recording. A long-term recording is a recording that will likely remain stored in theDHCT200 until it is expressly deleted pursuant to a user instruction or until it is over-written by a user scheduled recording.
After theDHCT200 receives user input identifying a buffered video presentation that is to be stored as a long-term recording, theDHCT200 stores the buffered video presentation as a long-term recording (as indicated in step703). One approach for storing a buffered video presentation as a long-term recording is to set a flag in a corresponding TSB management file identifying the video presentation as such, and to designate the storage space containing the buffered video presentation as not corresponding to a TSB204 (i.e., to de-allocate the storage space from a TSB240-i). Additional storage space having a capacity equal to the size of the de-allocated storage space may be allocated to the TSB204 to maintain a desired buffering capacity. In another embodiment, a video presentation that is buffered in a TSB204 may be converted to a long-term recording by being copied to another portion of a hard disk201.
FIG. 8 depicts a non-limiting example of a Recorded Programs List (RPL)screen800 that contains a list of recorded video presentations. TheRPL screen800 may be presented byPVR application277 in response to user input that may be provided via, for example, the activation of the List key430 (FIG. 4). ThePVR application277 may retrieve information from aPVR database278, as needed, for presentation via theRPL screen800. Furthermore, as in other UI screens, thePVR application277 may work in cooperation withwindow manager330 to present a user with a UI screen that is formatted in accordance with configuration data that is stored inDRAM252.
A recorded programs list860 contains recording entries corresponding to recorded video presentations. Each recording entry in the recorded programs list860 includes information such as the title of a recorded video presentation, the date it was recorded, the start time of the recording, and the length (i.e., play time) of the recording. In one embodiment, the arrow keys410 (FIG. 4) can be used to scroll through the recorded programs list860 and to highlight a desired recording entry.
The headingarea802 contains a heading for theRPL screen800. In this example, the heading area contains the heading “Recorded Programs List.” Thebottom area850 ofRPL screen800 contains information about the current functions of relevant keys on the remote control device400 (FIG. 4). As suggested inbottom area850, theplay key421 may be used to request the playing of a video presentation corresponding to a currently highlighted recording entry, the “B” key472 may be used to request recording options, and the “C” key473 may be used to request a recording schedule.
Video corresponding to the television channel to which theDHCT200 is currently tuned (for which audio may also be playing, and which typically corresponds to a video presentation occupying the full screen before the user is presented with RPL screen800) is displayed in avideo area830. Next to thevideo area830 is adetailed focus area810 that includes detailed information for a currently highlightedrecording entry820. In the current example, the currently highlightedrecording entry820 corresponds to the videopresentation title JAG822. Thedetailed focus area810 may include information such as the title of the video presentation (e.g., JAG), the quality of the recording (e.g., Good), the anticipated end of the recording duration (e.g., until erased). A user may request additional information by activating the Info key432 on the remote control device400.
In one embodiment, thedetailed focus810 area may include an icon or a letter (e.g., A or D) to indicate whether the video presentation was received as an analog or digital signal. Furthermore, the PVR application277 (FIG. 2) may identify a quality of a recording to a user based on a parameter that was employed by thecompression engine217 in compressing an analog signal or based on a bit-rate of a received digital signal.
FIG. 9 depicts a non-limiting example of aRecord Options screen900 that contains a list ofoptions902 related to the recording and/or buffering and of video presentations. A user may request theRecord Options screen900 by, for example, activating the “B” key472 (FIG. 4) while being presented with the RPL screen800 (FIG. 8). In this example, the list ofoptions902 includes anoption911 to sort recorded programs, anoption912 to manage a time shift buffer, and anoption913 to change recording settings. As suggested in thebottom area850, the user may activate the “C” key473 (FIG. 4) in order to return to the previously displayed screen (e.g., the RPL screen800). Thedetailed focus area810 provides information related to the currently highlightedoption912. In an alternative embodiment, aRecord Options screen900 does not include thevideo area830 or thedetailed focus area810, and/or is presented as a barker that overlays a preceding screen (e.g., the RPL screen800).
FIG. 10 depicts a non-limiting example of aBuffer Management screen1000 that contains a list ofoptions1002 related to the buffering of video presentations. A user may request theBuffer Management screen1000 by, for example, selectingoption912 while being presented with the Record Options screen900 (FIG. 9). Alternatively, theBuffer Management screen1000 may be requested via the activation of a dedicated key on a remote control device. In this example, the list ofoptions1002 includes anoption1011 to view a list of buffered programs, anoption1012 to manage a time shift buffer, and anoption1013 related to inter-channel buffering. These options1011-1013 will be discussed in more detail below.
FIG. 11 depicts a non-limiting example of aBuffer Size screen1100 that contains a list ofbuffer size options1102 for determining the size of one or more time shift buffers (TSBs). A user may request theBuffer Size screen1100 by, for example, selectingoption1012 while being presented with the Record Management screen1000 (FIG. 10). In this example, the list ofbuffer size options1102 includes a 30 minutebuffer size option1111, a 1-hourbuffer size option1112, and a 2-hourbuffer size option1113. Other buffer size options may be displayed by scrolling up or down the list ofbuffer size options1102. Selecting a buffer size option causes one or more TSBs to have a storage capacity that can accommodate a video stream having a play time indicated by the selected option.
FIG. 12A depicts a non-limiting example of anInter-Channel Buffering screen1200 that can be used to activate or de-activate inter-channel buffering. As used herein, inter-channel buffering refers to the ability to access a buffered video stream corresponding to a previously tuned television channel after effecting a change in television channels. A user may request theInter-Channel Buffering screen1200 by, for example, selectingoption1013 while being presented with the Record Management screen1000 (FIG. 10). A user may activate inter-channel buffering by selecting the “ON”option1201 and may de-activate inter-channel buffering by selecting the “OFF”option1202. In one embodiment, even after the “OFF”option1202 is selected, a user may subsequently press the buffer key436 (FIG. 4) prior to changing TV channels in order to activate inter-channel buffering with respect to the currently displayed channel.
FIG. 12B depicts a non-limiting example of anInter-Channel Buffering screen1210 that can be used to activate or de-activate inter-channel buffering. TheInter-Channel Buffering screen1210 is an alternative embodiment to the Inter-Channel Buffering screen1200 (FIG. 12A). A user may request theInter-Channel Buffering screen1200 by, for example, selectingoption1013 while being presented with the Record Management screen1000 (FIG. 10). A user may activate inter-channel buffering by selecting theoption1212 and may de-activate inter-channel buffering by selectingoption1212. Furthermore, the user may activate inter-channel buffering only with respect to “favorite” TV channels or video presentations by selectingoption1213.
A favorite channel or presentation may have been identified as such via user input. A list of favorite channels and/or presentations may be stored in a favorites database374 (FIG. 3). Selectingoption1213 enables a user to access a buffered video stream corresponding to a previously displayed channel after the user changes television channels (e.g., via the Channel +/−key434), only if the previously displayed channel or presentation had been designated as a “favorite.”
Inter-channel buffering with respect to only favorite channels or presentations may be implemented by thePVR application277. For example, after a user requests a change in television channels, thePVR application277 may first access an IPG database372 (containing a television program schedule) (FIG. 3) to identify the currently displayed channel or presentation. The PVR application may then access afavorites database374 to determine whether the currently displayed channel or presentation had been designated as a favorite. If the currently displayed channel or presentation had been designated as a favorite, then thePVR application277 may enable the user to access a buffered video presentation corresponding to the favorite channel or presentation after a change in television channels is implemented. Otherwise, thePVR application277 disables access to the buffered video presentation corresponding to the channel that was displayed prior to a change in channels.
FIG. 13A depicts a non-limiting example of an Buffered Programs List (BPL)screen1300 that contains a list of buffered video presentations. A user may request theBPL screen1300 by, for example, selectingoption1011 while being presented with the Record Management screen1000 (FIG. 10). Alternatively, theBPL screen1300 may be requested via the activation of a dedicated key on a remote control device.
A buffered programs list1306 contains buffer entries corresponding to buffered video presentations. Each buffer entry in the buffered programs list1306 includes information such as the title of a buffered video presentation, the broadcast time of the original video presentation, the available time of the buffered video presentation (i.e., the beginning and end times of the buffering), and an indication as to whether the buffered video presentation is designated to be recorded (i.e., stored as a long-term recording). In one embodiment, the arrow keys410 (FIG. 4) can be used to scroll through the buffered programs list1306 and to highlight a desired buffer entry.
Thebottom area850 ofBPL screen1300 contains information about the current functions of relevant keys on the remote control device400. As suggested inbottom area850, theplay key421 and therecord key426 may be used to request the playing and recording, respectively, of a video presentation corresponding to a currently highlightedbuffer entry1302. The “A”key471 may be used to request the recording of all the buffered video presentations, the “B” key472 may be used to request a UI screen for sorting the buffered video presentation, and the “C” key473 may be used to “exit” from theBPL screen1300.
FIG. 13B depicts a non-limiting example of an Buffered Programs List (BPL)screen1310 that may be presented to a user in response to the activation of the record key426 (FIG. 4) while being presented with the BPL screen1300 (FIG. 13A). As shown inFIG. 13B, the highlightedentry1302 indicates, as shown at1324, that the buffered video presentation “News at 11”1322 is designated to be recorded. As soon as the user confirms this designation (e.g., by activating the “C” key473 (FIG.4)), then the buffered video presentation “News at 11”1322 is stored as a long-term recording.
FIG. 14 depicts a non-limiting example of aSort screen1400 that contains a list ofoptions1402 for sorting a list of buffered programs (e.g., the buffered programs list1460 shown inFIG. 13). A user may request theSort screen1400 by, for example, activating the “B” key472 (FIG. 4) while being presented with the BPL screen1300 (FIG. 13A). In this example, the list ofoptions1402 includesoptions1411,1412, and1413 for sorting a list of buffered programs based on broadcast time, title, and buffered length (e.g., play time), respectively. By selecting one of the options1411-1413, the user is presented with a list of buffered programs that are sorted accordingly (i.e., by broadcast time, title, or buffered length). Additional sorting options may also be selected by using the up and downarrows411 and412 on the remote control device400 to browse through the list ofoptions1402 and by then using theselect button420 to select a desired sorting option. Additional sorting options may include, for example, an option for sorting a list of buffered programs based on their theme (e.g., comedy, drama, action, etc.).
FIGS. 15A,15B, and15C depict non-limiting examples of Sorted Buffered Programs List (SBPL) screens1500,1510, and1520, respectively. TheSBPL screen1500 contains a buffered programs list1306 that is sorted alphabetically by title. A user may request theSBPL1500 by, for example, selecting thetitle option1412 while being presented with the Sort screen1400 (FIG. 14).
As shown inFIG. 15B, theSBPL screen1510 contains a buffered programs list1306 that is sorted based on the play-time duration of the buffered video presentations. As a result, a buffered video presentation that has a longer play-time is listed above another video presentation that has a shorter play-time. A user may request theSBPL1510 by, for example, selecting the bufferedlength option1413 while being presented with the Sort screen1400 (FIG. 14).
As shown inFIG. 15C, theSBPL screen1520 contains a buffered programs list1306 that is sorted based on the broadcast time of the buffered video presentations. In other words, a video presentation that has an earlier start time is listed above another video presentation that has a later start time. A user may request theSBPL1520 by, for example, selecting thebroadcast time option1411 while being presented with the Sort screen1400 (FIG. 14).
In an alternative embodiment, a UI screen for achieving functionality described herein may have fewer, additional, and/or different components and/or may have a different layout than is shown inFIGS. 8-15. For example, in accordance with one embodiment, among others, a UI screen may not include avideo area830, a headingarea802, adetailed focus area810, and/or abottom area850.
It should be emphasized that the above-described embodiments of the invention, particularly any “preferred embodiments”, are merely possible examples, among others, of the implementations, setting forth a clear understanding of the principles of the invention. Many variations and modifications may be made to the above-described embodiments of the invention without departing substantially from the principles of the invention. All such modifications and variations are intended to be included herein within the scope of the disclosure and invention and protected by the following claims.