US 20080138033 A1
A method for receiving media content of multiple display channels at a digital home communication terminal (DHCT), comprising receiving first media content corresponding to a first display channel at a first tuner of the DHCT, receiving second media content corresponding to a second display channel at a second tuner of the DHCT, and presenting to a user of the DHCT a plurality of options to receive third media content using one of the first and second tuners at a time overlapping at least in part with a time in which the first and second media content are received.
1. A method for receiving media content of multiple display channels at a digital home communication terminal (DHCT), comprising:
receiving first media content corresponding to a first display channel at a first tuner of the DHCT;
receiving second media content corresponding to a second display channel at a second tuner of the DHCT; and
presenting to a user of the DHCT a plurality of options to receive third media content using one of the first and second tuners at a time overlapping at least in part with a time in which the first and second media content are received.
2. The method of
3. The method of
4. The method of
5. The method of
6. The method of
7. The method of
8. The method of
9. The method of
10. The method of
11. The method of
12. The method of
13. A digital home communication terminal (DHCT), comprising:
a first tuner configured to receive first media content corresponding to a first display channel;
a second tuner configured to receive second media content corresponding to a second display channel;
a memory with logic; and
a processor configured with the logic to enable a user of the DHCT to effectuate reception by the DHCT of third media content using one of the first and second tuners at a time overlapping at least in part with a time in which the first and second media content are received.
14. The DHCT of
15. The DHCT of
16. The DHCT of
17. The DHCT of
18. The DHCT of
19. The DHCT of
20. A system, comprising:
a digital home communication terminal (DHCT) residing in a subscriber television system (STS), the DHCT comprising:
a first tuner configured to receive first media content corresponding to a first display channel;
a second tuner configured to receive second media content corresponding to a second display channel;
a memory with logic; and
a processor configured with the logic to provide a graphical user interface (GUI) that enables a user of the DHCT to effectuate reception by the DHCT of third media content using one of the first and second tuners at a time overlapping at least in part with a time in which the first and second media content are received; and
a television configured to present the GUI, the GUI configured to provide the user an option which, when selected, effectuates which of the first media content or second media content to delete to receive the third content.
This application is a continuation of U.S. patent application Ser. No. 10/143,123, filed May 10, 2002, which claims priority to U.S. provisional application having Ser. No. 60/290,315, filed May 11, 2001, both of which are entirely incorporated herein by reference.
This application is related to copending U.S. patent application Ser. No. 10/143,647, filed May 10, 2002, which is entirely incorporated herein by reference.
The present invention is generally related to television systems, and, more particularly, is related to personal video recording.
With recent advances in digital transmission technology, subscriber television systems are now capable of providing much more than the traditional analog broadcast video. In implementing enhanced programming, the home communication terminal device (“HCT”), otherwise known as the set-top box, has become an important computing device for accessing media content services (and media content within those services) and navigating a user through a maze of available 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 and personal video recording.
Typically, a DHCT is connected to a cable or satellite, or generally, a subscriber television system, and includes hardware and software necessary to provide the functionality of the digital television system at the user's site. Some of the software executed by a DHCT may be downloaded and/or updated via the subscriber television system. Each DHCT also typically includes a processor, communication components, and memory, and is connected to a television or other display device, such as a personal computer. 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 personal computer or even an audio device such as a programmable radio, as will be appreciated by those of ordinary skill in the art.
DHCTs are typically capable of providing users with a very large number and variety of media content choices. As the number of available media content choices increases, viewing conflicts arise whereby the user must choose between watching two or more media content instances (e.g., discrete, individual instances of media content such as, for a non-limiting example, a particular television show or “program” episode), all of which the user would like to view. Further, because of the large number of viewing choices, the user may miss viewing opportunities. Buffering of media content instances in memory, or more recently, in storage devices (e.g., hard disk drives, CD-ROM, etc.) coupled to the DHCT, has provided some relief from the conflict in viewing choices while providing personal video recording functionality. However, current buffering mechanisms for personal video recording make inefficient use of tuner and buffer resources for a plurality of display channel changes using buffering mechanisms that operate under single-tuner constraints and/or assumptions. Therefore, there exists a need to exploit multi-tuner functionality to make more efficient use of DHCT resources.
Thus, a heretofore unaddressed need exists in the industry to address the aforementioned deficiencies and inadequacies.
The preferred embodiments of the invention can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present invention. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
The preferred embodiments of the invention now will be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. One way of understanding the preferred embodiments of the invention includes viewing them within the context of a subscriber television system, and more particularly within the context of a media client device, such as a digital home communication terminal (DHCT). The DHCT provides for user interaction with what is displayed on a television and what is buffered into an associated storage device. Although other communication environments are considered to be within the scope of the preferred embodiments, the preferred embodiments of the invention will be described in the context of a DHCT that receives media content from a headend over a subscriber network as one example implementation among many.
Because the preferred embodiments of the invention can be understood in the context of a subscriber television system environment, an initial description of a subscriber television system is followed with a description of the types of transmission signals that are included in the subscriber television system, in addition to further description of the headend and DHCT (and coupled storage device) that are included within the subscriber television system. The preferred embodiments of the invention include controlling rules for displaying and buffering media content in a multi-tuner, multi-display channel changing environment. Thus, the description that follows the DHCT discussion will help to illustrate what resources are included in tuning, displaying and/or storing media content at the DHCT, and how those resources are managed and allocated to implement a plurality of display channel changes.
Following the discussion on resource allocation and management is a description of input variables, and how the input variables are used in the context of a rule based system of the preferred embodiments to produce a set of consequences and/or outputs to make decisions on what media content to receive and buffer during a plurality of display channel changes.
This description of input variables in the context of a rule-based system is followed by a description of some example implementations that rely on the rule based system to provide for efficient functioning of the personal video recording (PVR) system of the DHCT
The preferred embodiments of the invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those having ordinary skill in the art. Furthermore, all “examples” given herein are intended to be non-limiting, and are provided as an exemplary list among many other examples contemplated but not shown.
One embodiment of the invention is generally implemented as part of a subscriber television system (STS), which includes digital broadband delivery systems (DBDS) and cable television systems (CTS). As a non-limiting example, a subscriber television system (STS) and its operation will be described initially, with the understanding that other conventional data delivery systems are within the scope of the preferred embodiments of the invention.
The STS 10 typically delivers broadcast video signals as digitally formatted signals in addition to delivering traditional broadcast analog video signals. Furthermore, the system can typically support one way broadcast services as well as both one-way data services and two-way media content and data services. The two-way operation of the network typically allows for user interactivity with services, such as Pay-Per-View programming, Near Video-On-Demand (NVOD) programming according to any of several known NVOD implementation methods, Video-on-Demand (VOD) programming (according to any of several VOD implementation methods), and interactive applications, such as Internet connections.
The STS 10 also provides the interfaces, network control, transport control, session control, and servers to access media content from media content services, and distributes media content to DHCT users. As shown in
Media content provided by one or more content providers (not shown) is communicated by the content providers to one or more headends 11. From those headends 11 the media content is then communicated over a communications network 18 that includes a plurality of HFC access networks 17 (only one HFC access network 17 is illustrated). The HFC access network 17 typically comprises a plurality of HFC nodes 13, each of which may serve a local geographical area. The hub 12 connects to the HFC node 13 through a fiber portion of the HFC access network 17. The HFC node 13 is connected to a tap 14 that is connected to a digital home communication terminal (DHCT) 16. Coaxial cables are typically used to couple nodes 13 and taps 14 because the electrical signals can be easily repeated with RF amplifiers. As the high-level operations of many of the functions of an STS 10 are well known to those of ordinary skill in the art, further high level description of the overall STS 10 of
As depicted in
Analog Transmission Signals (ATSs) 60 shown in
Like the ATSs 60, the DTSs 64, 68, 72 each typically occupies 6 MHz of the RF spectrum. However, the DTSs 64, 68, and 72 are digital transmission signals consisting of 64- or 256-Quadrature Amplitude Modulated (QAM) digital signals formatted preferably using Moving Picture Experts Group (MPEG) standards such as MPEG-2 transport streams, allocated in a separate frequency range. The MPEG-2 transport stream enables transmission of a plurality of DTS types over each 6 MHz RF subdivision, as compared to a 6 MHz ATS. The three types of digital transport signals illustrated in
MPEG-2 transport may be used to multiplex video, audio, and data in each of these Digital Transmission Signals (DTSs). However, because an MPEG-2 transport stream allows for multiplexed video, audio, and data into the same stream, the DTSs do not necessarily have to be allocated in separate 6 MHz RF frequencies, unlike the ATSs 60 in one embodiment. On the other hand, each DTS is capable of carrying multiple broadcast digital media content instances, multiple cycling data carousels containing broadcast data, and data requested on-demand by the subscriber. Data is formatted, such as in Internet Protocol (IP), mapped into MPEG-2 packets, and inserted into the multiplexed MPEG-2 transport stream. Encryption can be applied to the data stream for security so that the data may be received only by authorized DHCTs. The authorized DHCT 16 is provided with the mechanisms to receive, among other things, additional data or enhanced services. Such mechanisms can include “keys” that are required to decrypt encrypted data.
Each 6 MHz RF subdivision assigned to a digital transmission signal can carry the video and audio streams of the media content instances of multiple television (TV) stations, as well as media content and data that is not necessarily related to those TV media content instances, as compared to one TV channel broadcast over one ATS 60 that consumes the entire 6 MHz. The digital data is inserted into MPEG transport streams carried through each 6 MHz frequency subdivision assigned for digital transmission, and then demultiplexed at the subscriber DHCT so that multiple sets of data can be produced within each tuned 6 MHz frequency span, or subdivision.
Although broadcast in nature, the carousel DTSs 68 and on-demand DTSs 72 offer different functionality. Continuing with
The carousel DTSs 68 preferably carry data formatted in directories and files by a Broadcast File System (BFS) (not shown), which is used for producing and transmitting data streams throughout the STS 10, and which provides an efficient means for the delivery of application executables and application media content and data to the DHCT, as will be described below. Media content and data received by the DHCT 16 in such manner can then be saved in the DHCT memory and/or transferred to the DHCT storage device for later use. The on-demand DTSs 72, on the other hand, can carry particular information such as compressed video and audio pertaining to subscriber requested media content instance preview and/or media content instance descriptions, as well as other specialized data information.
Preferably, the User-to-Network Download Protocol of the MPEG-2 standard's DSM-CC specification (Digital Storage Media-Command and Control) preferably provides the data carousel protocol used for broadcasting data from a server located at the headend 11, or located elsewhere. It also provides the interactive download protocol for reliable downloading of data from a server (possibly the same server) to an individual DHCT through the on-demand DTSs. Each carousel and on-demand DTS is preferably defined by a DSM-CC session. Therefore, some of the basic functionality reflected in the DHCT 16 when the DHCT does not have a local physical storage device is somewhat similar to a networked computer (i.e., a computer without a persistent storage device), in addition to traditional set top box functionality, as is well known to those of ordinary skill in the art. A DHCT 16 with a storage device reduces data access latency when the data is stored in the local physical storage device ahead of time.
Also shown in
In a typical system, the programming, services and other information from content providers can be distributed according to a variety of mechanisms. The input signals may be transmitted from sources to the headend 11 via a variety of transmission paths, including satellites (not shown), and terrestrial broadcast transmitters and antennas (not shown). The headend 11 can also receive content from a direct feed source 210 via a direct line 212. Other input sources from content providers include a video camera 214, an analog input source 208, or an application server 216. The application server 216 may include more than one line of communication. One or more components such as the analog input source 208, the input source 210, the video camera 214, and the application server 216 can be located external to the headend 11, as shown, or internal to the headend 11 as would be appreciated by one having ordinary skill in the art. The signals provided by the content or programming input sources can include a single media content instance or a multiplex that includes several media content instances.
The headend 11 generally includes one or more receivers 218 that are each associated with a content source. In one implementation, MPEG encoders, such as encoder 220, are included for digitally encoding local programming or a real-time feed from the video camera 214, or the like. In other implementations, an encoder can be located externally to the headend 11. The encoder 220 outputs the respective compressed video and audio streams corresponding to the analog audio/video signal received at its input. For example, the encoder 220 can output formatted MPEG-2 or MPEG-1 packetized elementary (PES) streams or transport streams compliant to the syntax and semantics of the ISO MPEG-2 standard, respectively. The PES or transport streams may be multiplexed with input signals from a switch 230, the receiver 218 and a control system 232. The multiplexing logic 222 processes the input signals and multiplexes at least a portion of the input signals into a transport stream 240. The analog input source 208 can provide an analog audio/video broadcast signal which can be input into a modulator 227. From the modulator 227, a modulated analog output signal can be combined at a combiner 246 along with other modulated signals for transmission into a transmission medium 250. Alternatively, an analog audio/video broadcast signal from the analog input source 208 can be input into the modulator 228. Alternatively, an analog audio/video broadcast signal can be input directly from the modulator 227 to the transmission medium 250. The analog broadcast media content instances are transmitted via respective RF channels, each assigned for transmission of an analog audio/video signal such as National Television Standards Committee (NTSC) video, as described in association with
The switch, such as an asynchronous transfer mode (ATM) switch 230, provides an interface to an application server 216. There can be multiple application servers 216 providing a variety of services such as a Pay-Per-View service, including video on demand (VOD), a data service, an Internet service, a network system, or a telephone system. Service and content providers may download content to an application server located within the STS 10. The application server 216 may be located within the headend 11 or elsewhere within the STS 10, such as in a hub 12. The various inputs into the headend 11 are then combined with the other information from the control system 232, which is specific to the STS 10, such as local programming and control information, which can include, among other things, conditional access information.
The headend 11 contains one or more modulators 228 to convert the received transport streams 240 into modulated output signals suitable for transmission over the transmission medium 250 through the network 18. Each modulator 228 may be a multimodulator including a plurality of modulators, such as, but not limited to, QAM modulators, that radio frequency modulate at least a portion of the transport streams 240 to become output transport streams 242. The output signals 242 from the various modulators 228 or multimodulators are combined, using equipment such as the combiner 246, for input into the transmission medium 250, which is sent via the in-band delivery path 254 to subscriber locations (not shown). The in-band delivery path 254 can include DTS 64, 68, 72, and ATS 60, as described with
In one embodiment, the server 216 also provides various types of data 288 to the headend 11. The data, in part, is received by media access control functions 224 that output MPEG transport packets containing data 266 instead of digital audio/video MPEG streams. The control system 232 enables the television system operator to control and monitor the functions and performance of the STS 10. The control system 232 interfaces with various components, via communication link 270, in order to monitor and/or control a variety of functions, including the frequency spectrum lineup of the programming for the STS 10, billing for each subscriber, and conditional access for the content distributed to subscribers. Information, such as conditional access information, is communicated from the control system 232 to the multiplexing logic 222 where it is multiplexed into the transport stream 240.
Among other things, the control system 232 provides input to the modulator 228 for setting the operating parameters, such as selecting certain media content instances or portions of transport streams for inclusion in one or more output transport stream 242, system specific MPEG table packet organization, and/or conditional access information. Control information and other data can be communicated to hubs 12 (
The out-of-band data is transmitted via the out-of-band FDS 76 of the transmission medium 250 by, but not limited to, a Quadrature Phase-Shift Keying (QPSK) modem array 226. Two-way communication utilizes the RDS 80 of the out-of-band delivery path 256. Hubs 12 (
The transmission medium 250 distributes signals from the headend 11 to the other elements in the subscriber television system, such as the hub 12, the node 13, and subscriber locations (
The DHCT 16 further preferably includes one or more processors, such as processor 344, for controlling operations of the DHCT 16, and a tuner system 345, which preferably comprises two tuners, tuner1 354 and tuner2 358, for tuning into a particular television channel or frequency to display media content and for sending and receiving various types of data or media content to and from the headend 11. The DHCT 16 may include, in other embodiments, more than two tuners for receiving downloaded (or transmitted) media content. The tuner system 345 can select from a plurality of transmission signals (
According to another embodiment of the invention, a telephone modem (not shown) in the DHCT 16 can be utilized for upstream data transmission and the headend 11, the hub 12 (
The DHCT 16 includes a signal processing system 314, which comprises demodulating system 313 and transport demultiplexing and parsing system 315 (herein demultiplexing system) to process broadcast media content and/or data. One or more of the systems of the signal processing system 314 can be implemented with software, a combination of software and hardware, or preferably in hardware. The demodulating system 313 comprises functionality for RF signal demodulation, either an analog transmission signal or a digital transmission signal. For instance, the demodulating system 313 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 transmission, the demultiplexing system 315 is bypassed and the demodulated analog TV signal that is output by the demodulating system 313 is instead routed to an analog video decoder 316. The analog video decoder 316 converts the analog video signal (i.e., the video portion of a media content instance that comprises a video portion and an audio portion, such as NTSC video) received at its input into a respective non-compressed digital representation comprising a sequence of digitized pictures and their respective digitized audio. In one implementation, the video consists of a sequence of fields spaced apart at approximately one-sixtieth of a second. A pair of consecutive fields constitutes a picture. The odd field contains the odd-numbered lines of the picture and the even field contains the even-numbered lines of the picture. The analog video decoder 316 outputs the corresponding sequence of digitized pictures and respective digitized audio. Each picture is a two dimensional entity of picture elements and each picture element contains a respective set of values. A picture element value comprises luminance and chrominance information that are representative of brightness and color information at the spatial location of the picture element within the picture.
Digitized pictures and respective audio output by the analog video decoder 316 are presented at the input of a compression engine 317. Digitized pictures and respective audio output by the analog video decoder 316 can also be presented to a bypass 308, which acts through an interface (not shown) such as ITU-656 (International Telecommunications Union or ITU), and is dedicated for non-compressed digitized analog video and audio, for display on the TV 341. The compression engine 317 is coupled to memory 349 and additionally to a local dedicated memory 309 that is preferably DRAM, for input and processing of the input digitized pictures and the respective digitized audio. Alternatively, the compression engine 317 can have its own integrated memory (not shown). The compression engine 317 processes the sequence of digitized pictures and digitized audio and converts them into a video compressed stream and an audio compressed stream, respectively. The compressed audio and video streams are produced in accordance with the syntax and semantics of a designated audio and video coding method, such as specified by the MPEG-2 audio and MPEG-2 video ISO (International Organization for Standardization or ISO) standard, so that they can be interpreted by a video decoder 323 (also known as a video decompression engine) and an audio decoder 325 (also known as an audio decompression engine) for decompression and reconstruction at a future time. Each compressed stream includes a sequence of data packets containing a header and a payload. Each header includes a unique program identification, or PID, associated with the respective compressed stream.
The compression engine 317 multiplexes the audio and video compressed streams into a transport stream, such as an MPEG-2 transport stream, for output. Furthermore, the compression engine 317 can compress audio and video corresponding to more than one media content instance in parallel (e.g., from two tuned analog TV signals when the DHCT 16 possesses multiple tuners) and to multiplex the respective audio and video compressed streams into a single transport stream. The output of compressed streams and/or transport streams produced by the compression engine 317 is preferably input to the signal processing system 314. Parsing capabilities within the signal processing system 314 allow for interpretation of sequence and picture headers, for instance, annotating their locations within their respective compressed stream for future retrieval from a storage device 373. A compressed analog media content instance (e.g., TV program episode or show) corresponding to a tuned analog transmission channel can be output as a transport stream by the signal processing system 314 and presented as input for storage in the storage device 373 via an interface 375 as will be described below. The packetized compressed streams can be also output by the signal processing system 314 and presented as input to the media engine 322 for decompression by the video decompression engine 323 and the audio decompression engine 325 for its display on the TV 341, as will be described below.
The demultiplexing system 315 can include MPEG-2 transport demultiplexing. When tuned to carrier frequencies carrying a digital transmission signal, the demultiplexing system 315 enables the separation of packets of data, corresponding to the compressed streams of information belonging to the desired media content instances, for further processing. Concurrently, the demultiplexing system 315 precludes packets in the multiplexed transport stream that are irrelevant or not desired, such as packets of data corresponding to compressed streams of media content instances of other media content signal sources (e.g., other TV channels), from further processing.
The parsing capabilities of the demultiplexing system 315 includes reading and interpreting the received transport stream without disturbing its content, such as to interpret sequence and picture headers, for instance, to annotate their locations and corresponding time offset within their respective compressed stream for future retrieval from the storage device 373. Thus, the components of the signal processing system 314 are capable of QAM demodulation, forward error correction, and demultiplexing MPEG-2 transport streams, and parsing elementary streams and packetized elementary streams, among other functions. A compressed media content instance corresponding to a tuned carrier frequency carrying a digital transmission signal can be output as a transport stream by the signal processing system 314 and presented as input for storage in the storage device 373 via the interface 375 as will be described below. The packetized compressed streams can be also output by the signal processing system 314 and presented as input to the media engine 322 for decompression by the video decompression engine 323 and the audio decompression engine 325, and output to an output stage 348, as will be described below.
One having ordinary skill in the art will appreciate that the signal processing system 314 will preferably include other components not shown, including memory, decryptors, samplers, digitizers (e.g., analog-to-digital converters), and multiplexers. 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 present invention, including analog signals (e.g., NTSC) that bypass one or more elements of the signal processing system 314 and are forwarded directly to the output stage 348. Further, outputs presented at corresponding next-stage inputs for the aforementioned signal processing flow may be connected via accessible memory 349 in which the outputting device stores the output data and the inputting device thereafter inputs the output data written to memory 349 by the respective outputting device. Outputting and inputting devices include the analog video decoder 316, the compression engine 317, the media engine 322, the signal processing system 314, and components or subcomponents thereof. Further, it will be understood by those having ordinary skill in the art that components of the signal processing system 314 can be spatially located in different areas of the DHCT 16. Further, it will be understood by those having ordinary skill in the art that, although the components of the signal processing system 314 are illustrated as being in communication with an incoming signal from the communications interface 342, the signal may not necessarily be in the order shown for all signals.
The DHCT 16 also includes the media engine 322, which includes the digital video decoder 323 (or video decompression engine), the digital audio decoder 325 (or audio decompression engine), the output stage 348, and the bypass 308, and other digital signal processing components not shown, as would be appreciated by those having ordinary skill in the art. For example, the demultiplexing system 315 is in communication with the tuner system 345 and processor 344 to effect reception of digital compressed video streams, digital compressed audio streams, and data streams corresponding to one or more media content instances to be separated from other media content instances and/or streams transported in the tuned transmission channel and to be stored in a first part (not shown) of DRAM 352 of DHCT 16 assigned to receive packets of one or more media content instances. Other dedicated memory may also be used for media content instance packets.
Furthermore, while conducting this process, the demultiplexing system 315 demultiplexes and separates desired compressed streams from the received transport stream without disturbing its content. Further, the demultiplexing system 315 parses (i.e., reads and interprets) compressed streams such as to interpret sequence headers and picture headers, and deposits a transport stream carrying compressed streams of a media content instance into DRAM 352. The processor 344 causes the transport stream in DRAM 352 to be transferred to the storage device 373 via the interface 375. Under program control by the processor 344, the demultiplexing system 315, in communication with the digital video decoder 323, the storage device 373, and the processor 344, effects notification and/or transfer of received packets of one or more compressed streams corresponding to one or more media content instances from a first part of DRAM 352 to a second part (not shown) of DRAM 352 assigned to the digital video decoder 323 and the digital audio decoder 325. In other embodiments, the media engine 322 can have access to a dedicated localized DRAM, such as A/V decoder memory 306 to facilitate such transfers. Upon demultiplexing and parsing the transport stream carrying one or more media content instances, and in communication with the processor 344, the signal processing system 314 outputs to DRAM 352 ancillary data in the form of a table or data structure (not shown) comprising the relative or absolute location of the beginning of certain pictures in the compressed media content instance for convenience in retrieval during future operations.
In another embodiment, according to a plurality of tuners, and respective number of demodulating systems 313, demultiplexing systems 315, and signal processing systems 314, a respective number of broadcast digital media content instances are received and routed to the hard disk 300 of the storage device 373 simultaneously while performing the necessary data annotations for each of the respective compressed media streams for their future retrieval from storage device 373. Alternatively, a single demodulating system 313, a single demultiplexing system 315, and a single signal processing system 314, each with sufficient processing capabilities can serve to process more than one digital media content instance. One or more of the received broadcast digital media content instances routed to the storage device 373 can be routed simultaneously to the media engine 322 for decoding and display to the TV 341.
In another embodiment according to the aforementioned description, a first tuner, for example tuner1 354 of tuning system 345 receives an analog video signal corresponding to a first media content instance and a second tuner, for example tuner2 358 receives a digital compressed stream corresponding to a second media content instance. The first media content instance is processed as an analog signal and the second media content instance is processed as a digital compressed stream as described above. The compressed digital version of the analog video signal or the second media instance, or both, can be routed to the storage device 373 while simultaneously performing the respective data annotations required for future retrieval. Additionally, either or both of the media instances can be routed simultaneously to the media engine 322 for decoding and display on the TV 341.
In one implementation, the compression engine 317 can output formatted MPEG-2 or MPEG-1 packetized elementary streams (PES) inside a transport stream, all compliant to the syntax and semantics of the ISO MPEG-2 standard. Alternatively, the compression engine 317 can output other digital formats that are compliant to other standards. The digital compressed streams output by the compression engine 317 corresponding to a media content instance are preferably deposited in local memory 309 for the compression engine 317 and routed to the demultiplexing system 315. The demultiplexing system 315 parses (i.e., reads and interprets) the transport stream generated by the compression engine 317 without disturbing its content, such as to interpret picture headers, and deposits the transport stream into DRAM 352. The processor 344 causes the transport stream in DRAM 352 to be transferred to the storage device 373. While parsing the transport stream, the demultiplexing system 315 outputs to DRAM 352 ancillary data in the form of a table or data structure (not shown) comprising the relative or absolute location of the beginning of certain pictures in the compressed media content stream for the media content instance for convenience in retrieval during future operations. In this way, random access operations such as fast forward, rewind, and jumping to a location in the compressed media content instance can be attained.
In another embodiment, according to a plurality of tuners, respective number of analog video decoders 316, and respective number of compression engines 317, the aforementioned compression of analog video and audio is performed and routed to the hard disk 300 of the storage device 373 simultaneously on a respective number of analog media content instances. Alternatively, a single compression engine with sufficient processing capabilities can serve to compress more than one analog media content instance.
The media engine 322 also includes the output stage 348. In one implementation, the output stage 348 can include a digital encoder (DENC) (not shown) for driving the TV display. In parallel to feeding a DENC, the output stage 348 can also route the video/audio signal for output in multiple formats. Such formats can include analog component YPbPr, which can be used in High Definition Television (HDTV), some standard televisions, and digital video disk (DVD) players. Another format can be RGB component for personal computer displays. Another format can include a digital version of an analog component, which is used with fiber optic cable connections. The DENC output can feed digital analog converters (DAC—not shown) for output as composite video (CVBS), also known as baseband (e.g., V-output connection in a VCR or DVD player). In other implementations, the luma and chroma signals can be kept separate to output “separate video” through DACs (e.g., S-video connection in a VCR or DVD player). The DENC output of the output stage 348 can also feed an RF channel 3 and 4 modulator (not shown) that feeds a DAC. In another implementation, the output stage 348 outputs in parallel through an ITU-656 output port, either for internal routing of the video or to drive an external DENC (e.g., for VCR recording). In other embodiments, the DENC can be external to the output stage 348. In other embodiments, a DENC internal to the output stage 348 can be used to drive an external DENC (not shown), and the external DENC can be used to drive a Channel 3 and/or 4 RF modulator.
The DHCT 16 also includes a media memory 305. These components can include software and/or hardware to compose and store graphical information created by the processor 344. These components enable the compositing of graphical data with video into a picture for a TV display as provided by capabilities in the media engine 322.
In one implementation, compressed video and audio streams received through an in-band tuner of the tuner system 345 or read from the local storage device 373 is deposited continuously into a compressed audio and video section 306 of the media memory 305. Thereafter, one or more video decompression engines 323 within the media engine 322 decompress compressed MPEG-2 Main Profile/Main Level video streams read into the video decompression engine 323 from the compressed video buffer 306 of the media memory 305. Each picture decompressed by the video decompression engine 323 is written to a reconstruction portion 307 of the media memory 305, where the reconstructed pictures are retained.
Alternatively, the pictures may be decompressed in the video decompression engine 323, then scaled down as they are being reconstructed in a procedural fashion by feeding data of the reconstructed pictures in raster-scan order from the video decompression engine 323 to a video scaling unit (not shown). According to this alternative, the scaled down reconstructed picture can be stored in one of multiple scaled video picture buffers (not shown) in media memory 305 in raster-scan order as they are reconstructed, such that a respective scaled video picture buffer is dedicated to the motion video picture of a program or video object (read from the local storage device 373) and included in the displayed presentation.
Additionally, one or more digital audio decompression engines 325 in the media engine 322 can decode the compressed digital audio streams associated with the compressed digital video or read as an audio object from the local storage device 373 in a similar fashion, allocating respective buffers as necessary. It should be appreciated that in some implementations only one audio buffer may be required. Note that, in some embodiments, system memory 349 and media memory 305 can be unified as one physical memory device. It should be appreciated that the media memory 305 is a memory of finite number of bytes, and it serves as a repository for different data components. Compressed MPEG-2 video streams are deposited in A/V decoder memory 306 allocated for compressed video and compressed audio, as described above. Decompressed audio is fed into an audio port (not shown) for playback. Further information on the media memory and subcomponents thereof, in addition to other DHCT components can be found in the patent application entitled, DIGITAL SUBSCRIBER TELEVISION NETWORKS WITH LOCAL PHYSICAL STORAGE DEVICES AND VIRTUAL STORAGE, filed on Jul. 30, 2001, assigned a Ser. No. 09/918,376, assigned to Scientific Atlanta, Inc., and herein incorporated by reference.
One or more programmed software applications, herein referred to as applications, are executed by utilizing the computing resources in the DHCT 16. Note that an application typically includes a client part and a server counterpart that cooperate to provide the complete functionality of the application.
An application referred to as a navigator 355 is also resident in FLASH memory 351 for providing a navigation framework for services provided by the DHCT 16. The navigator 355 registers for and in some cases reserves certain user inputs related to navigational keys such as channel increment/decrement, last channel, favorite channel, etc. The navigator 355 also provides users with television related menu options that correspond to DHCT functions such as, for example, blocking a display channel or a group of display channels from being displayed in a display channel menu presented on a screen display.
The FLASH memory 351 also contains a platform library 356. The platform library 356 is a collection of utilities useful to applications, such as a timer manager, a compression manager, a configuration manager, a hyper text markup language (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 contain these utilities. Two components of the platform library 356 that are shown in
The window manager 359 provides a mechanism for implementing the sharing of the screen regions and user input. The window manager 359 on the DHCT 16 is responsible for, as directed by one or more applications, implementing the creation, display, and de-allocation of the limited DHCT 16 screen resources. It allows multiple applications to share the screen by assigning ownership of screen regions, or windows. The window manager 359 also maintains, among other things, a user input registry 350 in DRAM 352 so that when a user enters a key or a command via the remote control device 380 or another input device such as a keyboard or mouse, the user input registry 350 is accessed to determine which of various applications running on the DHCT 16 should receive data corresponding to the input key 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 380, the command is received by the receiver 346 and relayed to the processor 344. The processor 344 dispatches the event to the operating system 353 where it is forwarded to the window manager 359 which ultimately accesses the user input registry 350 and routes data corresponding to the incoming command to the appropriate application.
The SAM client 357 is a client component of a client-server pair of components, with the server component (not shown) being located on the headend 11, preferably in the control system 232 (
Applications can also be downloaded into DRAM 352 at the request of the SAM client 357, typically in response to a request by the user or in response to a message from the headend 11. In the example DHCT memory illustrated in
In one implementation, applications executing on the DHCT 16 work with the navigator 355 by abiding by several guidelines. First, an application utilizes the SAM client 357 for the provision, activation, and suspension of services. Second, an application shares DHCT 16 resources with other applications and abides by the resource management policies of the SAM client 357, the operating system 353, and the DHCT 16. Third, an application handles situations where resources are only available with navigator 355 intervention. Fourth, when an application loses service authorization while providing a service, the application suspends the service via the SAM (the navigator 355 will reactivate an individual service application when it later becomes authorized). Finally, an application is designed to not have access to certain user input keys reserved by the navigator 355 (i.e., power, channel+/−, volume+/−, etc.).
The MOD application 363 provides the user with lists of available media content titles for each media content instance to choose from and with media content instances requested by the user. The MOD application 363 provides media content to the user by engaging, typically, in a direct two-way IP (Internet Protocol) connection with VOD content servers (not shown) that would be located, in one embodiment, in the headend 11.
An executable program or algorithm corresponding to an operating system (OS) component, or to a client platform component, or to an application, or to respective parts thereof, can reside in and execute out of DRAM 352 and/or FLASH memory 351. Likewise, data input into or output from any executable program can reside in DRAM 352 or FLASH memory 351. Furthermore, an executable program or algorithm corresponding to an operating system component, or to a client platform component, or to an application, or to respective parts thereof, can reside in FLASH memory 351, or in a local storage device (such as the storage device 373) externally connected to or integrated into the DHCT 16 and be transferred into DRAM 352 for execution. Likewise, data input for an executable program can reside in FLASH memory 351 or a storage device and be transferred into DRAM 352 for use by an executable program or algorithm. In addition, data output by an executable program can be written into DRAM 352 by an executable program or algorithm and be transferred into FLASH memory 351 or into a storage device. In other embodiments, the executable code is not transferred, but instead, functionality is effected by other mechanisms.
Referring again to
The DHCT 16 includes at least one storage device 373 to provide storage for downloaded media content. The storage device 373 can be an optical storage device or a magnetic storage device, and is preferably a hard disk drive. The storage device 373 comprises storage for media content and/or data that can be written to for storage and later read from for retrieval for presentation. The storage device 373 preferably includes two hard disks 300 and 301, with each including a corresponding buffer space TSB1 376 and TSB2 378, as will be explained further below. Alternatively, the DHCT 16 can be coupled to two storage devices, each with one hard disk. Alternatively, a storage device can be used that uses different buffer spaces on one hard disk, or the storage device can include more than two hard disks, or platters. Throughout this disclosure, references relating to writing to or reading from the storage device 373, or references regarding recordings from or to the storage device 373 will be understood to mean that such read or write operations are occurring to the actual medium (for example, the hard disk 300 and/or 301) of the storage device 373. The storage device 373 is also comprised of a controller 379 that receives operating instructions from a device driver 311 of the operating system 353 (as described below) and implements those instructions to cause read and/or write operations to the hard disks 300 and/or 301.
The device driver 311 communicates with the storage device controller 379 to format the hard disks 300 and 301, causing the hard disks to be divided radially into sectors 301 and concentric circles called tracks 302, as illustrated by the schematic diagram n of the example hard disk 300 in
Referring again to
The temporary cache is implemented and managed to enable media content transfers from the temporary cache to the storage device 373, or, in concert with the insertion of a newly arriving media content into the temporary cache. In one implementation, the fast access time and high data transfer rate characteristics of the storage device 373 enables media content to be read from the temporary cache in memory 349 and written to the storage device 373 in a sufficiently fast manner. Orchestration of multiple simultaneous data transfer operations is effected so that while media content is being transferred from the cache in memory 349 to the storage device 373, new media content is received and stored in the temporary cache of memory 349. In other implementations, the downloaded media content is received through the communications port 374 in the DHCT 16 and then transferred directly to storage device 373, thus bypassing the temporary cache.
The operating system 353, the device driver 311, and the controller 379 communicate under program execution in the processor 344 and/or via the interrupt and messaging capabilities of the DHCT 16 and thus cooperate to create a special file in one of the hard disk sectors in each hard disk 300 and 301 called a file allocation table (FAT) (not shown). The FAT is where the operating system 353 stores the cluster and file information about each of the hard disks 300 and 301, and which clusters are assigned and associated with a file and thus used to store which media content instance files. The operating system 353 can determine where a file's data is located by using the directory entry (not shown) for the file and the entries of the FAT. The directory entry gives information about a directory such as its related files and subdirectories and create time, and special permissions. A FAT entry describes the physical locations of data associated with a media content downloaded to the hard disks 300 and 301 of the storage device 373. The FAT also keeps track of which clusters are free, or open, and thus available for use. Updates to the FAT are provided for by the operating system 353, or the device driver 311, or a combination of both. Writes to each of the hard disks 300 and 301 are coordinated between the PVR application 377 (described below), the operating system 353, the device driver 311, and the storage device controller 379.
The PVR application 377, the operating system 353, and the device driver 311 execute respective programmed instructions in the processor 344. The processor 344, the storage controller 379, and the demultiplexing system 315 communicate via interrupt and messaging capabilities of the DHCT 16. The PVR application 377, in communication with operating system 353, the device driver 311, the storage device controller 379, and the demultiplexing system 315, effects retrieval of compressed video streams, compressed audio streams, and data streams corresponding to one or more media content instances from the storage device 373. The retrieved streams are deposited in an output cache in the storage device 373 and transferred to DRAM 352, and then processed for playback according to mechanisms well known to those having ordinary skill in the art. In some embodiments, the media content instances are retrieved and routed from the hard disks 300 and/or 301 to the video and audio decoding system 323 and 325 simultaneously, and then further processed for eventual presentation on a display device or other device.
The PVR application 377 provides for media content recording functionality by enabling the temporary writing to, and if requested, more permanent recording (i.e., relatively permanent) to the storage device 373. Media content can be transmitted (or downloaded) from a remote location, such as, for example, a remote server located in the head end 11, or from a home communication network, or from other consumer electronic devices. Downloaded media content that is received at each tuner of tuner system 345 is temporarily buffered, or stored, on the hard disk of the storage device. The corresponding space on each hard disk is called a buffer space, or a time shift buffer (TSB). In a preferred embodiment, each tuner in tuner system 345 has a respective TSB. In one implementation, tuner1 354 receives media content for buffering to TSB1 376. Likewise, the second tuner 358 receives media content for buffering to TSB2 378. Moreover, media instances sourced from a device such as a camera attached to the DHCT 16 via the communication port 374 has a respective TSB (not shown). Note that buffering is understood to mean temporarily storing media content, received from a local attached device, or either from reception of a broadcast digital channel, and/or a digital compressed version of a broadcast analog channel, and/or data, into the buffer spaces (or TSBs) of the storage device 373.
Under normal operation, the PVR application 377 effectively associates a temporary recording designation with the media content received into the TSBs. The media content stored in the TSBs will either be deleted (i.e., the clusters storing the media content will be configured as writeable for eventual write operations that overwrite the media content within those clusters) or retained (through election by the user, as one example) as a permanent recording. A permanent recording will be understood to include media content that is stored for an extended period of time as decided by the user. Permanent recordings are stored in non-buffer clusters (i.e., not in clusters assigned to the TSBs) that are not used for the TSBs in instances when the user elects in advance to make a scheduled recording of a media content instance that has not yet been tuned to at the DHCT 16. A permanent recording can also be achieved by selecting a media content instance stored in the TSBs and designating the media content instance as permanent. In this latter implementation, the designated media content is stored in clusters that are configured from TSB clusters to permanent recording clusters (non-buffer clusters). To compensate for the re-designation of clusters to a permanent recording, the device driver 311 preferably assigns and associates an equivalent number of clusters to the TSB that it obtains from a pool of available unused and/or writeable (e.g., repossessed) clusters thus permitting continuance of normal TSB behavior and management. Thus, permanent recordings will preferably be more permanent than media content in the TSBs, and permanent recordings can eventually be deleted from the disk space, typically at the explicit request of a user, as one example.
There is a duration associated with the TSBs, which represents how much data is held by the TSBs. This duration could represent, in one embodiment, actual media content instance time. The PVR application 377, in such a time-duration embodiment, will preferably maintain a substantially constant buffer space capacity suitable for a certain duration of media content instance time, for example, 3-4 hours worth of media content instances. Media content instance-time tracking is related to hard disk space tracking if a constant data rate, or buffering rate, is assumed or estimated. In a preferred embodiment, the duration of the TSBs represents hard disk space. The PVR application 377 can set a buffer size capacity, for example 3 gigabytes (GB), and then track the disk space used for the TSBs to ensure a substantially constant TSB capacity. For example, before the PVR application 377 effects a write to the storage device 373, it can query the device driver 311 (through the operating system 353) to determine the available hard disk space. After the write operation, the PVR application 377 again can poll the device driver 311 to get an update on available hard disk space.
The TSBs can be managed according to several mechanisms. In one embodiment, each media content instance that is received at either of the tuners of tuner system 345 prompts the PVR application 377 to cause each media content instance to be downloaded to the hard disk 300 or 301 and associated as a media content instance file under a designated media content instance filename. This media content instance filename is recorded in a FAT that maintains a list of the corresponding clusters storing the media content instance file. The PVR application 377 also creates a management file that maintains a data record that preferably points to the corresponding filename and includes a data record that includes, among other elements, guide data and the receipt time of the downloaded media content instance. The guide data includes the scheduled start time and stop time of the downloaded media content instance as well as other attributes and information that pertain to the media content instance.
The receipt of the downloaded media content instance is also recorded by the PVR application 377 (through coordination with the operating system 353 and an internal clock 372) as a real-time value. The PVR application 377 is either alerted to the start of a media content instance, in one implementation, from a keypress event (e.g., when a user tunes to a desired display channel). In another implementation, the PVR application can use a polling or timing mechanisms (via timer 371, as one example) in cooperation with the internal real-time clock 372 and guide data. The PVR application 377 provides the operating system 353 with the scheduled stop time (from guide data, such as from an interactive program guide) of the downloaded media content instance in order to set up a timer interrupt (or in other embodiments, polls the operating system 353) with the operating system 353. The operating system 353, in coordination with the real-time clock 371 within the DHCT 16, alerts the PVR application 377 (
Further, the PVR application 377 preferably maintains the management files with an organization mechanism such as a linked list, wherein each management file is associated with each of the media content instances located on the hard disks 300 and 301. Read requests for one of the downloaded media content instances in the TSB 378 occurs by the PVR application 377 searching the linked list for the requested media content instance, and providing a graphics user interface (GUI) (not shown) on a display screen based on the information maintained in the corresponding management file. Furthermore, a bi-directional link-list mechanism can be employed for arbitrary entry and to search forward or backward in relation among media instances.
Further information pertaining to this embodiment for creating and maintaining the TSBs can be found in the patent application entitled, SYSTEM AND METHOD FOR CONTROLLING SUBSTANTIALLY CONSTANT BUFFER CAPACITY FOR PERSONAL VIDEO RECORDING WITH CONSISTENT USER INTERFACE OF AVAILABLE DISK SPACE, filed Dec. 6, 2001 under Ser. No. 10/010,270 and assigned to Scientific Atlanta, herein incorporated by reference.
Another embodiment for maintaining and managing the TSBs includes associating a single file for each TSB, and controlling the allocation and deallocation of clusters in the disk space at the device driver 311 level. In this embodiment, further described in the patent application entitled, DISK DRIVER CLUSTER MANAGEMENT OF TIME SHIFT BUFFER WITH FILE ALLOCATION TABLE STRUCTURE,” filed Dec. 5, 2001 under Ser. No. 10/005,628 and assigned to Scientific Atlanta, herein incorporated by reference, the PVR application 377 requests the allocation of disk space for a single file for each TSB. For each TSB 378, the device driver 311, implemented as either a separate software module, or integrated with the operating system 353, allocates enough clusters and assigns them to the respective file to meet the size requirement designated by the PVR application 377. Media content instances downloaded and written to the TSBs are preferably tracked by time. The device driver 311 provides a software generated pointer, called Normal Play Time (NPT), which points to locations within files and locations within media content instances within those files. Based on the Lightweight Stream Control Protocol, NPT can be thought of as the clock associated with a video asset (as distinguished from the real-time clock 372 for the DHCT 16).
For every file that is created for media content downloaded to the storage device 373, an NPT is generated. There is an NPT for the read head of the storage device 373 and for the write head of the storage device 373. For writing media content to the storage device 373 for a newly created file (e.g., a TSB1 file), an NPT is created for the write head of the storage device 373 with an initial value of zero. In one implementation, the device driver 311 receives a periodic interrupt (for example every 5-10 msec) set up by the PVR application 377 through the computer services of the operating system 353. This interrupt is synchronized with the internal real-time clock 372 of the DHCT 16 in order to advance the pointer (i.e., the NPT) at a substantially constant rate. The NPT continues to increase in value (from an initial value of zero) until the associated file is closed. For the read head of the storage device 373, the NPT starts at 0 at the start of the file, advances in real time in normal play mode, advances faster than real time in fast forward mode, decrements in rewind mode, and is fixed when the video is paused.
The PVR application 377 maintains a data structure for every downloaded media content instance. There are one or more data structures preferably maintained on the hard disks 300 and 301 of the storage device 373, but the data structures can also be maintained in memory 349. The data structures include, for example, the NPT values defining the start and end times of the downloaded media content instance, the real-time values corresponding to the start and end times of the media content instances, as well as the corresponding media content instance guide data, among other elements. The device driver 311 maintains the mapping between NPT and the cluster and sector locations of the media content in a separate look-up table data structure (not shown) preferably located on the hard disks 300 and 301. In one embodiment, the device driver 311 can sample the current write location (i.e., cluster and sector location provided by the storage device controller 379) as the write head of the storage device 373 advances and store that cluster and sector location in the look-up table data structure along with a corresponding NPT value. This sampling can occur, for example, every 5-10 msec. In an alternative embodiment, the device driver 311 can record an initial sample and through an estimation algorithm (e.g., interpolation) estimate file locations and locations within said files. When the PVR application 377 references a particular media content instance (for example where a user seeks to rewind to a downloaded media content instance in the hard disk 300), the PVR application 377 passes the stored start and stop NPT values for that media content instance to the device driver 311, and the device driver 311 determines the hard disk locations from the look-up table data structure. The PVR application 377 correlates NPT read values for locations within the media content instances to the real-time clock value. With the real-time start and stop values and guide data maintained in a data structure, as well as the correlated read-NPT to real-time values, the PVR application 377 can produce a GUI that provides the user with information that includes what portion of a buffered media content instance the user is currently viewing.
As described above, the user preferably permanently records from the TSBs by designating as permanent a currently viewed media content instance during real-time viewing or returning (e.g., rewinding) to any part of a media content instance in the TSBs and selecting record from a remote device 380, or alternatively, from selecting a record button (not shown) on the DHCT 16. An example remote control device 380 to provide input to the DHCT 16 is illustrated in
While tuner1 354 receives media content of the first display channel for storage into TSB1 376 and display on the TV 341, assume a user changes from the first display channel to the second display channel. In order to receive media content at tuner2 358, the operating system 353 (
In another implementation, if the second display channel is transmitted over the same center RF frequency as the first display channel, as determined by the operating system 353 (
Assume the user changed from the first display channel to the second display channel, and that the second tuner 358 is an available resource. The media content of the first display channel, in one embodiment, will not be “deleted” (i.e., written over or its associated clusters made writeable) but instead retained for now, and the media content (after the display channel change) will continue to be received at tuner1 354 and downloaded into TSB1 376 from the first display channel. The point in time when the user resources tuner2 358 to receive the second display channel is “marked” and stored in memory 349 and thereafter copied to a PVR application data structure (not shown) associated with the buffer spaces of the storage device 373 (
In an alternate implementation, memory 349 (
The amount of elapsed time deemed to be sufficient is determined by comparison to a first programmable threshold value. The threshold value can be preset at compilation time by the application developer. In one preferred embodiment, the programmer programs the threshold to have an initial default value that can be modified throughout the course of time by the viewer according to the viewer's preference via an interactive configuration application (not shown) in which the viewer makes selections in a displayed graphical user interface (GUI) by entering information with key presses or by entering alphanumeric information with an input device such as a remote control device 380 (
The PVR application 377 (
The PVR application 377 (
The return to the first display channel causes the PVR application 377 (
When the user decides to change display channels (e.g., switch to a third display channel), the media content of the third display channel can go to either TSB1 376 or TSB2 378. In one embodiment, according to a programmed behavior, when the media content of the third display channel is downloaded to one of these buffer spaces, the media content already stored there is deleted (e.g., overwritten or made writeable) in order to receive and store the media content of the third display channel. A user can implement a preference as to which buffer space media content to delete.
In other embodiments, a currently buffered display channel's media content is deleted after a display channel change according to a set of controlling rules based on the respective values of a set of input variables that effect one or more outcomes or resulting behaviors. The controlling rules are programmed by the application developer and employ measured input variables that preferably connote elapsed time as measured in the background throughout the course of time by the PVR application 377 (
The PVR application 377, the operating system 353, the controller 379, the general settings application 312, and the device driver 311 (
The scope of outcomes or actions conducted by the execution of the programmed controlling rules, include one or more of the following:
The order in the actions conducted can differ, and no particular order is implied by the list A-J described above. A tuner resource change comprises the discontinuation of receiving a display channel's media content, and receiving the media content of another display channel requested by the viewer. A display resource change comprises the discontinuation of displaying a received display channel's media content and displaying on the TV 341 the media content of a newly requested display channel. A buffer resource change comprises the discontinuation of a received display channel and deletion of the corresponding media content that is buffered, in addition to buffering the media content of another received display channel in the TSB.
With continued reference to
For the example implementations provided, it will be assumed that a newly requested display channel is to be both displayed on the television 341 and buffered, with the understanding that the preferred embodiments can be used to accomplish either one of these operations alone or in combination. A couple of considerations are worth noting in the context of proper resource management. For example, according to rules and precedences configured, and with continued reference to
Another consideration in resource management includes the fact that discontinuation will vary in the signal flow path and the resources affected, in some implementations, depending on whether the received display channel is analog or digital.
Thus as shown, the management of resources for tuning, displaying, and/or buffering media content from a plurality of display channels includes, in addition to the considerations mentioned above, determining whether the resources are processing analog signals, digital signals, or a combination of both.
Step 1203 includes receiving a request for a new display channel. For purposes of discussion, it will be assumed that the new display channel is provided as a digital signal, with the understanding that the steps provided herein can be generally applied for an analog signal, or a combination of analog and digital signals. Step 1204 includes discontinuing the display of the media content of the second display channel on a display device (e.g., TV). For example, if the second display channel was currently providing media content to the display device, such as that shown in the timing diagram of
Step 1205 includes determining a precedence for resourcing a newly requested display channel according to a set of controlling rules, as will be described below. If the rules mandate that the first display channel has precedence, then discontinue the buffering of the media content of the second display channel (step 1206,
In one implementation, the repossession of “buffering resources” of the received display channel to be displaced uses a form of bookkeeping. In one embodiment, the point on the hard disk (e.g., 300 or 301,
Another input variable can be the length of time that a buffered display channel's media content is displayed on TV. Whether a buffered display channel's media content is currently displayed or last displayed on TV may cause this input variable to be weighted more significantly in the controlling rules. Hence, the multiplicative coefficient of an input variable may be dynamically adjusted according to a user's viewing patterns. The relationship between the length of buffering elapsed time between media content of a first display channel currently being buffered to media content of a second currently buffered display channel can also be another input variable.
The relationship between the length of buffering elapsed time of a display channel's media content currently being buffered to its total time displayed on TV throughout the course of buffering can also be an input variable. Another input variable to the controlling rules can be whether a display channel currently being buffered is included in a favorites channel list, such as a list of preferred display channels selected or entered by the viewer during the course of a configuration session. A favorites channel list, as well as all preferences and configurations aforementioned herein are stored in memory (e.g., DRAM 352) and in non-volatile memory, such as FLASH memory 351 (
In one embodiment, when the favorites channel list is employed as input to the controlling rules, a different set of controlling rules is executed. Alternate values for thresholds that control relational input variables can be employed when the favorites channel list is part of the input to the controlling rules. Hence, if a display channel being buffered is in the favorites channel list, it will influence the controlling rules in a way more towards continuing its buffering (or equivalently, less likely of being displaced and discontinued due to sourcing the tuner and respective TSB for media content of a newly requested display channel).
An input variable may be designed to exhibit a non-linear range when controlled by a respective threshold or set of thresholds. A first input threshold is preferably assigned to control the value of a first variable. A first type of input variable may be assigned a value of “no significance” (e.g., zero) if below its respective first controlling threshold value. Furthermore, the value of a second type of input variable may be controlled with a first controlling respective threshold and a second respective controlling threshold. If the value of the second type of input variable is above or equal to a first respective controlling threshold but below a second respective controlling threshold value, it retains its original value. Furthermore, the value of a third type of input variable may be controlled with a first respective controlling threshold and a second respective controlling threshold but may be assigned a maximum value when its value is above a second respective controlling threshold value. As would be understood and appreciated by those having ordinary skill in the art, the comparison of an input variable's value to a threshold value may be based on programmable operations, including “if less than the value”, “less than or equal to”, “greater than”, “greater than or equal to”, “equal”, and/or “not equal.”
A fourth type of input variable may be controlled by assigning a respective “no significance” value indirectly or directly per a viewer's input. A fifth type of input variable may be controlled by assigning a respective “no significance” value indirectly or directly per a viewer's input to configure a desired buffering, tuning and/or display behavior during a configuration session. A sixth type of input variable may be controlled by assigning a respective “maximum value” indirectly or directly per a viewer's input. A seventh type of input variable may be controlled by assigning a respective “maximum value” indirectly or directly per a viewer's input to configure a desired buffering, tuning and/or display behavior during a configuration session. In this way, the value of some and possibly all input variables can be modified to a non-linear range of values according to their actual value. The actual value of an input variable can be a measured value, a user input value, or a default value assigned by the programmed application. Each input variable may be further weighted multiplicatively with a respective coefficient that pertains to the importance of the respective input variable with respect to the complete set of input variables employed by the controlling rules. For example, a first controlling rule has a first multiplicative coefficient for a first input variable and a second controlling rule has a second multiplicative coefficient for the same first input variable.
Throughout the course of time, the PVR application 377 (
Upon a viewer's input entered via an input device such as a remote control device 380 (
Prior to the execution of the controlling rules, pre-processing of the applicable input variables is preferably conducted. The pre-processing module 385 (
The following description will include an example implementation, based on
In the preferred embodiments, the buffering duration of the media content of the first display channel up to the point of the display channel change (to the second display channel) is compared to the buffering duration of the media content of the second display channel. For example, the user can be viewing a series of media content instances over a span of hours on the first display channel. The user then decides to look at the score of a football game on the second display channel. The point in the presentation of the media content instance of the first display channel when the user switched to the second display channel is “marked”, and this “mark”, the buffering duration, and the displayed duration for the first display channel are stored in a PVR data structure with its pertinent annotations (not shown). The user is now viewing the football game on the second display channel, which is preferably received at tuner2 358 and buffered to TSB2 378. The media content of the first display channel continues to be downloaded to TSB1 376. Assume the user waits a few minutes before the score comes up on the screen display for the football game, and then decides to go to a third display channel.
Assuming the two tuner DHCT illustrated in
If shortly after switching to the third display channel, the user decides to switch to a fourth display channel, the PVR application 377 (
With continued reference to
Step 1306 includes receiving user input requesting a third display channel. Unless the DHCT 16 contains additional tuners, a conflict arises, since one of the tuners (354 or 358) has to be resourced to receive the media content of the third display channel for display on the TV 341 (
If a minimum buffering duration threshold was not met for the buffering of the media content to its respective buffer, then the prioritizing continues to point A in
If the buffering of the media content to either buffer failed to meet a minimum threshold duration, then either tuner1 354 or tuner2 358 (
However, if the media content to both buffers was not buffered for an equal buffering duration, then the next step (step 1520) is to determine whether the media content of the first display channel was buffered for a longer duration than the media content of the second display channel (i.e., relational input variables). It will be understood by those of ordinary skill in the art that the reference comparison can be reversed. For example, step 1520 can just as easily be described as determining whether the second display channel was buffered for a longer duration, or described as whether the media content of the second display channel was buffered for a shorter duration, etc. If step 1520 results in an affirmative determination, the prioritizing steps continue to point C (
However, continuing the example, if the media content of the second display channel was buffered for 25 minutes, this buffering duration exceeds the threshold percentage of 50%, and thus a decision barker can be provided (step 1626) to enable the user to determine priority in this case. In one embodiment, the viewer configures when to allow the decision barker to be displayed by entering input during a configuration session. Furthermore, the viewer configures the percentage difference from the set threshold for when the decision barker is displayed. Alternatively, a decision barker is only presented to the viewer to enable the viewer to determine priority in cases deemed as a “close-case,” such as when near the percentage threshold. Alternatively, default threshold percentages can be provided in the software, or the user can configure these threshold percentages in a user interface screen at start-up, or at other times, or additional input variables can be evaluated.
The PVR application 377 (
The PVR application 377 (
It should be emphasized that the above-described embodiments of the present invention, particularly, any “preferred embodiments” are merely possible examples of implementations, merely setting forth a clear understanding of the principles of the inventions. Many variations and modifications may be made to the above-described embodiments of the invention without departing substantially from the spirit of the principles of the invention. All such modifications and variations are intended to be included herein within the scope of the disclosure and present invention and protected by the following claims.