Method and Apparatus for Scrub Preview Services

[0001] This application claims the benefit of U.S. Provisional Application No. 61/384,166, filed on Sep. 17, 2010, entitled “Method and Apparatus for Differentiated Scrub Preview Services,” and U.S. Provisional Application No. 61/428,776, filed on Dec. 30, 2010, entitled “Method and Apparatus for Processing Scrub Description,” which applications are hereby incorporated herein by reference.

[0002] This application relates to the following co-pending and commonly assigned patent application: Attorney Docket No. HW 83024853.1US, Ser. No. 13/233,882, filed Sep. 15, 2011, which application is hereby incorporated herein by reference.

[0003] The present invention relates generally to media processing, and more particularly to a system and method for scrub preview services.

[0004] In recent years, media consumption has dramatically increased. This has resulted in a rapid increase in available media content. Consequently, consumers of the media have to select from a large array of available media content. However, there is no easy mechanism for making this selection.

[0005] Consumers of textual data have a much better experience than media consumers due to the availability of summaries, snippets, keywords, etc. For example, short summaries of large textual content provide users with an abstract of the content. This allows the user to rapidly select the articles/web pages to read.

[0006] In contrast, media consumers have to sort through the actual footage of the media before selecting a suitable media (or a portion of the media) to watch. For example, in a typical media player, a consumer must use the forward button to play the media stream at a faster frame rate, which mutes the audio channel. Further, the user may want to watch only a certain portion of the media stream, e.g., the financial summary in a news feed so that he can judge whether the financial news is worth watching. However, the user is likely to be frustrated because of the difficulty in identifying the appropriate relevant portion of the media stream and the necessity to watch the media stream to get the needed summary. Such ineffective means introduce inefficiencies in media selection and result in a degraded user experience.

[0007] These and other problems are generally solved or circumvented, and technical advantages are generally achieved, by illustrative embodiments of the present invention.

[0008] In accordance with an embodiment of the present invention, a method of generating a media preview of a media stream comprises generating a preview data by extracting preview information from a media file to be streamed. The preview data comprises a multi-dimensional hierarchical data structure having a plurality of layers with increasing content of the preview information in each layer of the plurality of layers. The preview data is configured to provide an adaptive and scalable preview service.

[0009] In accordance with another embodiment of the present invention, a method of streaming media comprising a media preview comprises delivering a preview data comprising preview information from a media file to be streamed. The preview data comprises a multi-dimensional hierarchical data structure having a plurality of layers with increasing content of the preview information in each layer of the plurality of layers. The preview data is configured to provide an adaptive and scalable preview service.

[0010] In accordance with another embodiment of the present invention, a method of receiving a media preview of a media stream comprises sending a preview data request to a preview server. The preview data request comprises a request for preview data. The method further comprises receiving a preview data comprising preview information from a media file to be streamed. The preview data comprises a multi-dimensional hierarchical data structure having a plurality of layers with increasing content of the preview information in each layer of the plurality of layers.

[0011] In accordance with another embodiment of the present invention, an apparatus for generating a media preview of a media stream comprises a preview data generator. The preview data generator under various embodiments is configured to generate a preview data by extracting preview information from a media file to be streamed. The preview data comprises a multi-dimensional hierarchical data structure having a plurality of layers with increasing content of the preview information in each layer of the plurality of layers. The preview data generator is configured to provide preview data for an adaptive and scalable preview service.

[0012] In accordance with another embodiment of the present invention, an apparatus for streaming a media preview of a media comprises a preview data sender configured to deliver a preview data. The preview data comprises preview information for a media file being streamed. The preview data comprises a multi-dimensional hierarchical data structure having a plurality of layers with increasing content of the preview information in each layer of the plurality of layers. The preview data sender is configured to provide an adaptive and scalable preview service.

[0013] In accordance with another embodiment of the present invention, an apparatus for receiving media having a media preview comprises a preview data sender configured to send a preview data request to a preview server. The preview data request comprises a request for a preview data for a media file being received. The preview data receiver is configured to receive the preview data comprising preview information for the media file. The preview data comprises a multi-dimensional hierarchical data structure having a plurality of layers with increasing content of the preview information in each layer of the plurality of layers.

[0014] Advantageously, embodiments of the invention allow full video preview and ultra-fast preview start up capability even under narrow bandwidth conditions.

[0015] The foregoing has outlined rather broadly the features of an embodiment of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of embodiments of the invention will be described hereinafter, which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and specific embodiments disclosed may be readily utilized as a basis for modifying or designing other structures or processes for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims.

[0044] Corresponding numerals and symbols in the different figures generally refer to corresponding parts unless otherwise indicated. The figures are drawn to clearly illustrate the relevant aspects of the embodiments and are not necessarily drawn to scale.

[0045] The making and using of various embodiments are discussed in detail below. It should be appreciated, however, that the present invention provides many applicable inventive concepts that can be embodied in a wide variety of specific contexts. The specific embodiments discussed are merely illustrative of specific ways to make and use the invention, and do not limit the scope of the invention.

[0046] In the typical online media platforms or delivery systems today, on-demand media content (especially video) is presented via powerful media players which allow the users to randomly seek to any spot to continue the video playback. The media content is consumed either linearly (by default, for example, by clicking a web thumbnail which leads to a media playing in a media player) or randomly by the end user by dragging the play-head of the media player forward or backward to a random spot. These types of media consumption models do not provide the end users effective consumption of media content. The random drag (scrub) of play-head may appear to provide infinite flexibility to the end users, but in fact the dragging to a spot involves random guess work and users often have to watch the content for a little bit to decide if this is worth continuing or another random drag is in order.

[0047] Preview is a natural tool for people to sample the content of a video before watching it. Online video streaming traffic accounts for the lion's share of the internet traffic today and continues to grow. Customers are demanding for more content, more flexibility, more service capability, more personalization, and better qualities. Providing large amount of preview data can take up considerable network delivery resources. To control the consumption of delivery resources, e.g., the delivery network bandwidth consumption, the preview delivery service are limited to the network condition, resource availability, as well as service capabilities. However, such brute force restriction of preview content degrades experience for all customers.

[0048] As described further below, an adaptive scrub preview scheme can overcome these limitations. The problem of lacking reference information during the active consumption of online media (i.e., drag of play-head in a player to seek for a more desirable spot to continue) may be overcome with a scrub preview scheme. End users are provided a series of preview data such as preview images (or even lower resolution video clips) as the end users drag the play-head along the progress bar. Thus, the system greatly enhances active media consumption of the end users by allowing them to seek a preferred spot to continue the media consumption, and hence greatly improves the end user media consumption experience.

[0049] Embodiments of the invention describe an adaptive service to offer customers fair and superior service capability with the service provider being able to gain increased average revenue per user (ARPU). Embodiments of the present invention discloses a fair and differentiated preview service scheme including a differentiated scrub preview service scheme based on a multi-layer data structure, multi-stage delivery scheme, and offers multi-style presentation format. The proposed scheme as described in various embodiments can further improve user experiences, service personalization capability, as well as other preview service capabilities.

[0050] The adaptive scrub preview scheme as described in various embodiments is scalable, flexible and extensible. Some embodiments of the present invention provide an ultra-fast preview startup and switching functionality. Consequently, the scrub preview is capable of supporting preview functions in mobile network or other networks with limited bandwidth or networks with frequent bandwidth fluctuations. Some embodiments of the present invention provide dual view and toggle view scrub previews which offer richer service capability. Embodiments of the invention also offer additional preview styles for better personalized preview services.

[0051] A number of new features and advantages are provided by embodiments of the present invention. For example, one aspect relates to a system to support adaptive and scalable preview services with preview generation, preview delivery, and preview rending. Another aspect relates to an adaptive preview service scheme based on a multi-layer data structure, multi-stage delivery scheme, and provides multi-style presentation format. Yet another aspect relates to a differentiated scrub preview service scheme with flexible and personalization enabled service capability. Yet a further aspect relates to an adaptive and scalable preview service system that supports single or multiple service provider based preview for IP video delivery services.

[0052] Embodiments of the present invention provide advantages and distinctions over alternative technologies. In traditional preview system, the preview functions are usually simple, easy to use, but non-scalable, without personalization capability, with limited ability to adapt to the changing network and other environment conditions, and with little presentation flexibility and adaptation capability. In various embodiments, the present invention offers a wide range of scalable and adaptive preview service capabilities. The scalability and flexibility make it possible for an IP video delivery service provider to support differentiated preview services for added ARPU. A differentiated preview service scheme with a multi-layer data structure, multi-stage delivery scheme, and multi-style presentation format is also disclosed.

[0053] Scrub preview provides an incorporated service that is part of the IP video delivery service. Embodiments of the present invention offer means to support an independent differentiated preview service via a preview service system that offers both single and multiple service provider based preview service capability for IP video delivery services. Versions of scrub video are flexible, scalable and extensible preview scheme but might not support differentiated service scheme. Embodiments of the invention support a wide range of differentiated preview services.

[0054] A generic embodiment of the preview system for generating, delivering, and rendering the preview system will be described using FIG. 1, 22-24. A first set of embodiments of the present invention will be described for providing a scrub preview service based on preview data type using FIGS. 8-10. A second set of embodiments of the present invention will be described for providing a scrub description based preview service using FIGS. 11-21.

[0055] FIG. 1 describes a preview system for generating, delivering, and rendering the preview system in various embodiments of the invention.

[0056] Referring to FIG. 1, a typical preview system in accordance with embodiments of the invention includes three main components, namely Preview Generation (PG 10), Preview Delivery (PD 20), and Preview Rendering (PR 30). PG 10 takes a media stream and generates preview data. PD 20 delivers the preview data to the client (media player). The media player receiving the preview data renders the preview to the display (PR 30).

[0057] In various embodiments, the preview may be rendered using different type of client interface configurations. FIG. 2 to FIG. 7 illustrate six sample preview client interface configurations. Notice that these are merely examples. The present invention does not limit the type of preview interface configurations. One skilled in the art can easily implement the current invention in different interface configurations.

[0058] FIG. 2 schematically indicates the typical media player components and their relative positions in a media player. FIG. 2 illustrates a schematic of a media player 50 illustrating a preview using a scrub preview window 60 and a range indicator 70 indicating the validity of the preview.

[0059] FIG. 2 shows a reduced size scrub preview window 60 which can also be used for the description based scrub preview as will be described further below (FIGS. 11-21). The size of the scrub preview window 60 may vary from small to full player window size depending on application needs. When a media player user initiates a scrub preview, the user drags the play-head forward or backward along the preview bar.

[0060] The preview bar may be the playback progress bar, or it may be a separate bar. The granularity of the preview is, in general, proportion to the length of the video. To offer personalized experience, however, a scalable preview rendering function may be realized using one or more embodiments of the present invention. Furthermore, a localized scalable preview rendering capability can be achieved where the scalability of the preview is proportional to the play-head dragging speed with locality sensitivity. Users can easily browse through a video from the beginning to the end or back and forth. A user can also start the playback instantly at any preview position and start to watch the video thereafter. The preview description data stream delivery scheme optimizes the video preview start up time and ensures the preview playback has no glitch.

[0061] FIG. 3 illustrates a schematic of a media player 50 illustrating a preview using an overlay preview window 80. FIG. 4 illustrates a schematic of a media player 50 illustrating a preview using a convoy preview window 90. FIG. 5 illustrates a schematic of a media player 50 illustrating a preview using tile preview windows 110. FIG. 6 illustrates a schematic of a media player 50 illustrating a preview with list preview 120. FIG. 7 illustrates a schematic of a media player 50 illustrating a preview using thumbnails preview 130.

[0062] In various embodiments, the preview delivery service may be adapted based on some discrimination functions or service configurations to control the delivery resources consumption, e.g., the delivery network bandwidth consumption. In various embodiments, a service provider, may provide several classes of services, SC(1), SC(2), . . . SC(X). Different classes of services may be set apart by the service capability, the subscription fees, and other suitable parameters as may be identified by one skilled in the art. Customers subscribing to a higher class subscription, e.g., SC(X), may get better Quality of Service (QoS) and/or Quality of Experience (QoE) guarantees whereas customers subscribing to a lower class subscription, e.g., SC(1), may get significantly less service capability support compared with that of the higher class subscription customer.

[0063] For instance, a SC(X) subscriber may get the best type of preview configuration, the highest amount of description data, the most flexibility to preview a video, and the highest quality with the highest resolution of the preview video. In contrast, a SC(1) subscriber may experience some service capability loss and may only get the minimum amount of data delivered to its player with a minimum support on the preview configurations and a minimum flexibility on how the video can be previewed. Hence, while the SC(X) subscriber may enjoy a full range of preview service capabilities and personalize the service based on its own preference, the SC(1) subscriber may only enjoy a limited preview service capability with limited personalization.

[0064] Because of such differentiation between different customers, a service provider can balance the resource distribution when the network resource or other related types of resources are limited. Accordingly, this type of differentiated preview service can provide fair services to its subscriber i.e. higher paying customers receive better service than lower paying customers.

[0065] Further details on implementing an embodiment of the invention is described using FIGS. 8 and 9.

[0066] FIG. 8 illustrates operations in accordance with an embodiment of the invention for preview generation.

[0067] Different types of preview data D(i), i=[1,I], are first defined (step 210). For instance, let a first type of preview data D(1) may be a preview video data, a second type of preview data D(2) may be a preview audio data, a third type of preview data D(3) may be keyframe images, a fourth type of preview data D(4) may be preview content description text, a fifth type of preview data D(5) may be preview content description image, a sixth type of preview data D(6) may be a preview of relevant images, a seventh type of preview data D(7) may be a preview relevant text, etc.

[0068] The preview data may comprise a hierarchical structure. In other words, multiple layers of preview data may be used, each layer having more information than an underlying layer. For example, a higher layer may provide a higher resolution preview, a longer length preview, and/or video parameters e.g. color versus grayscale, bitrate etc. In a hierarchical preview data having J layers, the j^th layer of the type D(i) data can be denoted as P(j)|D(i), j=[1,J]. For instance, if D(1) represents preview video data, P(1)|D(1) could be the first layer of the preview video data with a resolution 120×90 in gray scale, P(2)|D(2) could be the second layer of the preview video data with a resolution 240×180 in gray scale, and so on.

[0069] Next, the service class is defined (step 220). Let service class SC(x), x=[1,X], be the preview service types offered by a service provider with service class SC(X) being the highest level of service class or VIP service class. The VIP service class provides consumers the ultimate service capability and flexibility and let service class SC(1) be the lowest level of service class, e.g., cheapest service which offers a minimum preview service capability.

[0070] In addition, user specified parameters may also be defined (step 230). For example, β(k)|D(i) defines the user specified parameter for preview data type D(i) to be delivered to the client. For instance, β(1)|D(1) may represent a low resolution gray scale video, β(2)|D(1) may represent a low resolution color video, β(3)|D(1) may represent a medium resolution video, β(4)|D(1) may represent a high resolution video, β(1)|D(4) may represent a minimum text description, β(2)|D(4) may represent a moderate text description, and β(3)|D(4) may represent a maximum text description, etc.

[0071] For each type of service, a maximum allowed service class profile is defined (step 240). For example, a service class profile SCP_max(x)=[P(j¹*)|D(1), P(j²*)|D(2), . . . , P(j^I*)|D(I)] where P(jⁱ*)|D(i) denotes the maximum layers of data for D(i) type of preview data. Thus, maximum allowed service class profile SCP_max(x) is the highest possible preview that is available.

[0072] As illustrated in step 250, an instance service class profile for each user L is defined as SCP^ins(x)=[P(j¹′)|D(1), P(j²′)|D(2), . . . , P(j^I′)|D(I)] where P(j^I′)|D(i) denotes the specified layers of data for D(i) type of preview data with jⁱ′≦jⁱ*. That is, the service provider may specify a set of rules for the preview data delivery that corresponds to each parameter to identify the layer associated for each preview data type D(i). In various embodiments, a default setting maybe used based on user preferences and profiles as well as the service class level she subscribes to.

[0073] In one or more embodiments, the client may also interactively adjust the preview service using some simple click based interfaces at the client side if her subscription level includes such service support. That is, the default instance service class profile SCP_ins(x)|L default may or may not equals to instant service class profile SCP_ins(x)|L instant. But, in various embodiments, SCP_ins(x)|L default or SCP_ins(x)|L instant cannot exceed beyond the maximum allowed service class profile SCP_max(x). The selected type (parameter) of preview service capability shall be translated into an adjustment or adaptation of a new or different set of preview data being delivered to the client by the server.

[0074] An embodiment of the invention for preview delivery will be described using FIG. 9.

[0075] A server receives a preview service request from a client (step 260). Once a server receives a preview service request indicating a default or instant service class profile with Q(x)|Ldefault or Q(x)|Linstant. The server translates the request into the corresponding service class profile, e.g., SCP_ins(x)|L default or SCP_ins(x)|L instant (step 270). Next, the server parses the requested profile by extracting the appropriate layer of the preview data, e.g., P(j¹′)|D(1)=120×90 color video (step 280). The extracted preview data is packaged and scheduled into a preview data stream. The preview data stream is delivered to the client side from which the preview request arose (step 290). All these steps may be performed in a single edge server or alternatively over a combination of network nodes, depending on the content delivery system capability and configurations. Once the client receives the preview data package, it decodes the package. The preview data may be rendered based on a default player setting or a user specification, and enables the user to enjoy the preview content instantly. Synchronization to the original media stream may be needed so that the preview data represents a particular location on the original media stream.

[0076] A differentiated preview service can be implemented for any kind of preview service. In the following, a sample embodiment for differentiated scrub preview service scheme is discussed. Several types of scrub previews including keyframe based scrub preview, description based scrub preview, and dual view scrub preview may be used in various embodiments of the invention. With differentiated scrub preview service, a highest class subscriber SC(X) may get the dual-view scrub preview support with both the scrub description data and the keyframe data delivered to its player. However, a lowest class subscriber SC(1) may experience some service capability loss and may only get one or two lower layers of the scrub description data delivered to its player. Hence, while the highest class subscriber SC(X) may enjoy a full scrub preview service and personalize the service based on its own preference, the lowest class subscriber SC(1) may only enjoy a coarse level scrub preview presented in a single text based style. When the network resource or other related types of resources are limited or constraint, this type of differentiated scrub preview service can help a service provider to balance the resource distribution and provide fair services to its subscriber.

[0077] In yet another embodiment of the present invention, an independent preview service can be offered. Any user can subscribe to the preview service with or without the subscription to the VoD or real time video delivery service. A user subscribed to the preview service can be connected directly to the preview server at her request. The server shall deliver the preview content to the user based on her subscriber service class, the user profile, the network and device condition, etc. In this embodiment, the preview service server maybe connected to multiple video delivery servers that are part of a single or multiple IP video delivery service providers.

[0078] FIG. 10 illustrates operations in accordance with an embodiment of the invention for preview rendering.

[0079] Referring to FIG. 10, a client, e.g., media player send a request for preview data (Step 1010). The media player may also send further user information such as a user specified information β (described above) for preview data requested (Step 1020). For instance, the media player may request that the first layer data may be transmitted as a low resolution gray scale video. The media player receives the corresponding preview data (Step 1030). Next, the media player renders the preview data to a display (Step 1040).

[0080] Another embodiment of the present invention using description based preview will next be described using FIGS. 11-21.

[0081] Embodiments of the present invention extend the scrub preview scheme to provide ultra-fast preview startup functionality. Instead of keyframe based scrub preview, in this embodiment of the present invention, description based scrub previews are used. The preview can start instantly without affecting the playback of the video, even in very low bandwidth network conditions. In a separate embodiment, the present invention describes the systems and scheme to achieve an additional scrub preview style called dual view scrub preview that takes advantage of both the description based and the keyframe based scrub preview. The dual view scrub preview offers additional personalized service capability. Embodiments of the present invention address the system and method to realize the description based scrub preview as well as the dual view scrub previews in a networked media distribution system with an online media player.

[0082] FIG. 11 illustrates a scrub description preview system in accordance with embodiments of the invention.

[0083] Referring to FIG. 11, the preview description system in accordance with embodiments of the invention includes three main components, namely Preview Description Generation (PDG 310), Preview Description Delivery (PDD 320), and Preview Description Rendering (PDR 330). This is similar to the scrub preview system discussed in above using FIG. 1.

[0084] PDG 310 is a process to extract and prepare necessary preview description, i.e., the scrub description data, for effective delivery and rendering. PDG 310 may happen either during an Ingest Process or after the Ingest Process. If the Content Delivery Process is a multi-step process, the PDG 310 may happen in any step. In various embodiments, the PDG 310 may generate additional content description metadata beyond the existing metadata in order to support the Fast Media Preview feature.

[0085] PDD 320 is a process whereby necessary Preview Description data and other metadata are delivered to the end user media player for preview rendering. The detailed algorithm of when and how to deliver which preview description data file(s) will be described further below using FIGS. 15 and 16.

[0086] PDR 330 is a process by which delivered preview description data, i.e., the scrub description data files are rendered to the end user as play-head is being dragged to seek a desired position. The PDR 330 process is sufficiently general so that it can be implemented easily by any player with a simple PlugIn module in various embodiments.

[0087] The description based scrub preview may be implemented in a stand-alone preview system. Alternatively, it may be an add-on layer to the original keyframe based scrub preview system. In addition, in one or more embodiments, it can be employed in combination with the keyframe based scrub preview to achieve dual-view scrub preview or toggled scrub preview. For ease of presentation, we shall use scrub description in the following discussion. A scrub description is a set of text that can be used to describe the content of the media or the information associated with the content of the media at a particular time frame, maybe displayed in a static or dynamic manner, and can facilitate media preview.

[0088] Embodiments of the PDG, PDD, and PDR implemented a description based scrub preview in a stand-alone preview system will be described.

[0089] FIG. 12 illustrates operations of generating description based scrub preview in a stand-alone preview system (PDG 310 of FIG. 11).

[0090] PDG 310 includes scrub description data extraction, scrub description management data generation, i.e., manifest file and index file creation, and scrub description data stream creation components. In accordance with embodiments of the invention, the preview data should satisfy several requirements to facilitate a fast scrub preview function.

[0091] First, the scrub description data should be small in size. To provide full video preview and ultra-fast preview start up capability especially in narrow bandwidth conditions, the preview media data stream, i.e., the scrub description data, is very small in size. Consequently, delivery of the preview media data stream will not hinder the delivery of the original media data stream or affect the playback experience of the original media data stream. To achieve that, the scrub description data is designed to be compact.

[0092] Second, for a quality preview experience, the preview content should capture the essence of the original media data stream. That is the scrub description should tender accurate content information about the particular segment of the video content in preview.

[0093] Third, to offer fast playback switching from any preview point to the corresponding original media stream point and vice versa, it is desired that the scrub description data streaming is well synchronized with the original media stream.

[0094] FIG. 13, which includes FIGS. 13A and 13B, illustrates one sample embodiment using aligned scrub description scheme, wherein FIG. 13A illustrates a scrub description data structure and FIG. 13B shows an example.

[0095] Embodiments of the invention use a scalable description scheme to facilitate scalable full video preview and fast preview start up. The length of the video is denoted a total time length Γ. The total time length Γ is determined for a given video stream (step 1210). Assume the level of scalability is K, i.e., there are K layers of description available for preview, from the coarsest layer 1 to the finest layer K (step 1220).

[0096] Referring to FIG. 13A, a plurality of layers (1, 2, . . . , K) for the preview data D is illustrated. In each layer, the media stream length is divided into a number of time segments. The duration of the time segments decreases with increasing layer thereby increasing the amount of preview data.

[0097] The scrub description for each layer is defined over each time segment (step 1240). As schematically illustrated in FIG. 13A, the i^th scrub description of the k^th layer denoted as D(i, k) is defined. The i^th scrub description of the k^th layer D(i, k) represents the preview description covering a i^th time segment of the k^th layer F(i, k). The total number of scrub descriptions (I_k) in a layer k is defined. That is,

$\sum _{i=1}^{I_k}\Gamma \left(i,k\right)=\Gamma ,$

k=[1, K]. For example, as illustrated in FIG. 13A, the first scrub description of the first layer D(1, 1) has a longer time segment than the first scrub description of the second layer D(1, 2).

[0098] In various embodiments, the scrub description of layer k may be either aligned or not aligned with the scrub description of layer k−1. Here, if for i=[1,I_k],

$\Gamma \left(i,k\right)=\sum _{i^{*}=j}^{J_i}\Gamma \left(i^{*},k-1\right),$

layer k−1 is deemed to be aligned to layer K. To facilitate localized scalability, most embodiments of the invention use an aligned scheme.

[0099] FIG. 13B illustrates an example using the embodiments of the scrub description data structure described above. As illustrated in FIG. 13A, the first layer is divided into three time segments while the second layer is divided into seven time segments. Each time segment in each layer contains a scrub description. For example, the first scrub description in the first layer is “Toyota recalls.” As illustrated in FIG. 13B, a user may be able to preview the third scrub description of the first layer D(3,1) or the sixth scrub description of the second layer D(6,2).

[0100] To improve user experience, especially personalized preview experience, a second dimension scalability, description scalability is also desirable. That is, instead of a single scrub description D(i, k), H degrees of description D(h, i, k) may be implemented for the i^th scrub description of the k^th layer. The lowest degree (h=1) may use the shortest description, i.e., the most abstract version of the description. The highest degree (h=H) may use the longest description, i.e., the most detailed version of the description.

[0101] FIG. 14 illustrates one sample embodiment showing more than one degree of freedom of scrub description. In FIG. 14, two degrees of freedom is selected and therefore two preview windows are displayed by the media player 50. In various embodiments, the scrub preview degree may be selected based on the specific user preference profiles. Alternatively, in one embodiment, the lowest description (h=1) may be displayed by default until the end user specifies (or alternatively requests) a different degree for display. A user may also easily toggle the views for different description details, i.e. different degree views, using hot keys or control buttons.

[0102] Evidently, i^th time segment of the k^th layer Γ(i, k) helps to foster the alignment between scrub description D(h, i, k) or D(i, k) and the original media content. To enable fast playback, a multi-layer media segmentation scheme followed by the multilayer scrub description generation process maybe employed in various embodiments.

[0103] To enable a quality preview experience, the scrub description D(i, k) should accurately describe the content stream within the time frame F(i,k). To achieve that, many scrub description D(i, k) extraction schemes may be used as known to one skilled in the art. For example, the extraction scheme may be selected based on preprocessing the media stream.

[0104] In one sample embodiment, scrub description D(i, k) maybe generated using the content description metadata. Content description metadata may be generated from many different sources including manual annotation, semi-automatic annotation, and automatic annotations which may include video content analysis, audio content analysis, text analysis, and speech recognition. Some part of the content description metadata may also be collected using web crawling.

[0105] To achieve fast media preview even in narrow bandwidth conditions, the scrub description D(i.k) should, in general, be small in size while content description metadata for different content may vary in size. Hence a scrub description extraction process is often necessary to generate scrub description D(i,k) for a given video. Many different extraction schemes can be used in various embodiments. In one or more embodiments, semantic and context based analysis may be used for providing the best extraction results. Alternatively, in some embodiments, key phrase based extraction may provide an easy to implement and fast executable scheme. The present invention does not limit the type of extraction schemes that can be used for scrub description D(i,k) generation.

[0106] To improve user experience, a layered flexible description scheme may be used in various embodiments. For instance:

	<scruball>
	<scrub class = ‘description’ degree=2 ......>
	<degree 1>......
	</degree 1>
	<degree 2>.......
	</degree 2>
	</scruball>

[0107] The scrub descriptions of different layers and different degrees may be saved in the same file or different files depending on different configuration requirements. Noticeably, in most cases, it is desirable to save the descriptions in the same layer into the same file to reduce management and delivery cost.

[0108] Once the scrub description data is extracted, the manifest file and an index file to facilitate description based scrub preview shall be generated.

[0109] The index file listing the data structure of the scrub description is generated (step 1250). Information such as total number of layers K, total number of scrub descriptions (I_k) in a layer k, and time segments Γ(i, k) maybe saved in the index file. Using the index file, a media player can easily and quickly allocate the scrub description data. The index file indicates explicitly the location of scrub description D(h, i, k) enabling the player to quickly extract the scrub description from the scrub description file and display in an user friendly manner for preview.

[0110] A manifest file is generated (step 1260). The manifest file may include different description and metadata to facilitate different uses of the description based scrub preview. For instance, the preview files location, the overall metadata, such as title, genre, and producer info, and some scene description info, annotations, etc., may be included in the manifest file. Noticeably, although, in one embodiment, the manifest file is packaged separately from the scrub description data file, in another embodiment, it may be packaged into the same file. Also, in one embodiment, the manifest and the index file maybe compliant with the original scrub preview manifest and index files whereas in another embodiment they may be different.

[0111] FIGS. 15 and 16 illustrate a detailed description of the operations of the PDD 320 (FIG. 11) in accordance with embodiments of the invention.

[0112] For the following description, assume T₀ is the time when a video stream Vm is being delivered from the edge server to the client for playback, ΔT is the minimum buffer length for the player to start video playback, T^D_M is the starting time of the scrub description manifest file being delivered, T^D*_M is the ending time of the manifest file being delivered, T^D_I is the starting time of the scrub description index file being delivered, T^D*_I is the ending time of the index file being delivered, T^D(k) is the starting time of the k^th scrub description data being delivered, and T^D*(k) is the ending time of the k^th scrub description data being delivered. Let B^th(t) denote the available bandwidth between the server and the client for content delivery at time t, R_p(t) denote the media player playback bitrate for Vm at time t, R_vm(t) denote the minimum delivery bitrate of Vm at time t to prevent playback jitter at the client, R^D(t) denote possible delivery bitrate of the preview file data stream at time t, and ΔR is a heuristic bitrate offset value to deal with short time bandwidth variations.

[0113] In the following sample embodiment, we assume different layers of the scrub description data are packaged in different files where F^D(k) denotes the k^th layer scrub description data file with size SF^D(k). The manifest file with a file size SF^D_M is denoted as F^D_M, and the index file with the file size SF^D_I is denoted as F^D_I. A skilled in art can easily modify the embodiment when different layers of the scrub description data are packaged in a single preview file or when different degrees of the scrub description data are packaged in separate files. The minimum buffer length ΔT is governed by many factors, such as the GOP size of a compressed video. Since there are many literatures available in the field, a skilled in the art should be able to calculate minimum buffer length ΔT based on the specific application requirement. Hence, a specific algorithm is not provided here.

[0114] FIG. 15 illustrates a scheduling algorithm for a standalone preview system for the operations of the preview description delivery in accordance with an embodiment of the invention.

[0115] At a first step 1510, the bit rate at the starting time B^th(T₀) is compared with the minimum delivery bitrate of Vm at the starting time to prevent playback jitter at the client R_vm(T₀). If the available bandwidth is positive after allowing for a margin for various fluctuations, the scrub data file will be transmitted. In contrast, if there is no available bandwidth, bit rate adaptation will be undertaken as explained below in step 1610. The first file to be transmitted is the manifest file, which is transferred at a rate set by the available bandwidth (Step 1530). Accordingly, at step 1520, at t=T^D_M=T₀, if B_th(t)>R_vm(t), start delivering manifest file F^D_M with rate R^D_M, where R^D_M=R^D(T₀)−ΔR, & R^D(T₀)=B_th(T₀)−R_vm(T₀). If B_th(T_M)−R_vm(T_M) is not positive, additional bit rate adaptation may be necessary and therefore go to Step 1610. At step 1610, bitrate adaptation is performed such that B_th(t)>R_vm(t). Then delivery of the manifest file F^D_M• is started.

[0116] The time after completing the delivery of the manifest file F^D_M with rate R^D_M is

$T_m^{D*}=T_0+\frac{{\mathrm{SF}}_M^D}{R_M^D},$

Therefore, at this ending time, the transmission of the index file is started (Steps 1540 and 1550) provided there is sufficient bandwidth. In other words, at time

$t=T_M^{D*}=T_I^D\&T_I^D=T_0+\frac{{\mathrm{SF}}_M^D}{R_M^D},$

if B_th(t)>R_vm(t), start delivering index file F^D_I with rate R^D_I=R^D(T_M)−ΔR, & R^D(T_M)=B_th(T_M)−R_vm(T_M). If B_th(T_M)−R_vm(T_M) is not positive, additional bit rate adaptation may be necessary and therefore go to Step 1620. At step 1620, bitrate adaptation is performed such that B_th(t)>R_vm(t). Then delivery of the index file F^D_I is started.

[0117] The time after completing the delivery of the index file F^D_I is the end time

$T_I^{D*}=T_0+\frac{{\mathrm{SF}}_M^D}{R_M^D}+\frac{{\mathrm{SF}}_I^D}{R_I^D}.$

Therefore, at this ending time, if there is sufficient bandwidth, i.e., B_th(t)>R_vm(t), the sending of the first layer of the scrub description file F^D(1) is started (Steps 1560 and 1570), i.e., at

$t=T_I^{D*}=T^D\left(1\right)\&T^D\left(1\right)=T_0+\frac{{\mathrm{SF}}_M^D}{R_M^D}+\frac{{\mathrm{SF}}_I^D}{R_I^D},$

if B_th(t)>R_vm(t), start delivering F^D(1), with rate R^D=R^D(T_I)−ΔR, & R^D(T_I)=B_th(T_I)−R_vm(T_I). Again, if however if B_th(t)<R_vm(t), the go to Step 1630 for further adjustments. At step 1630, bitrate adaptation is performed such that B_th(t)>R_vm(t). Then delivery of the first layer of the scrub description file F^D(1) is started.

[0118] After completing the sending of the first layer of the scrub description file, the higher layers of the scrub description data are sent if there is sufficient bandwidth (Steps 1580 and 1590), i.e., B_th(t)>R_vm(t). In other words, at t=T^D*(k−1)=T^D(k), if B_th(t)>R_vm(t), start delivering F^D(k), k=2, 3, . . . . If not, go to step 1640 for adjustments. At step 1640, bitrate adaptation is performed such that B_th(t)>R_vm(t). Then delivery of the k^th layer of the scrub description file F^D(k) is started.

[0119] When different degrees of the scrub descriptions are packed in different files, one added flexibility is to deliver the lowest degree first to further save bandwidth and deliver the higher degree ones on demand or only when there is extra bandwidth. The schedule algorithm can be easily modified accordingly.

[0120] FIG. 16 illustrates a scheduling algorithm for a standalone preview system for the operations of the preview description delivery in accordance with an embodiment of the invention, wherein the scheduling algorithm delivers granular layers from within the layers of the scrub description data.

[0121] In this embodiment, unlike the embodiment of FIG. 15, layers of the scrub description data D(i,k) are not delivered sequentially for k=[1,K]. Instead, a particular set of layers, k¹, k², . . . k^Q, is picked based on a decision criteria. In one embodiment, the decision criteria is selected as

$k^q=K\frac{g^q}{\mathrm{Gn}}$

where granularity selection parameter g^q, qε[1,Q] defines the granularity levels, and Gn defines the total levels of granularities. The granularity selection parameter g^q may be specified by the user, a user preference function, a bandwidth adaptation function, or other functions that can jointly optimize resource and user preferences.

[0122] Referring to FIG. 16, the operations proceed similar to FIG. 15 in transferring the manifest file and the index file. Therefore, at steps 1510 and 1520, at time t=T^D_M=T₀, if B_th(t)>R_vm(t), delivery of manifest file F^D_M is initiated with a rate R^D_M, where R^D_m=R^D(T₀)−ΔR, & R^D(T₀)=B_th(T₀)−R_vm(T₀). Otherwise at step 1610, bitrate adaptation is performed such that B_th(t)>R_vm(t). Then delivery of the manifest file F^D_M• is started.

[0123] At steps 1530 and 1540, and as described above, at time

$t=T_M^{D*}=T_I^D\&T_I^D=T_0+\frac{{\mathrm{SF}}_M^D}{R_M^D},$

if B_th(t)>R_vm(t), delivery of index file F^D_I is started with a rate R^D_I, where R^D_I=R^D(T_M)−ΔR, & R^D(T_M)=B_th(T_M)−R_vm(T_M). Otherwise, at step 1620, bitrate adaptation is performed such that B_th(t)>R_vm(t). Then delivery of the index file F^D_I is started.

[0124] Unlike the embodiment described in FIG. 15, the first layer of the scrub description file is not transmitted. Rather, the k¹ layer will be transmitted. The time after completing the delivery of the index file F^D_I is the end time

$T_I^{D*}=T_0+\frac{{\mathrm{SF}}_M^D}{R_M^D}+\frac{{\mathrm{SF}}_I^D}{R_I^D}.$

Therefore, at this ending time, if there is sufficient bandwidth, i.e., B_th(t)>R_vm(t), the sending of the k¹ layer of the scrub description file F^D(k¹) is started (Steps 1710 and 1720). In other words, at time

$t=T_I^{D*}=T^D\left(k^1\right)\&T^D\left(k^1\right)=T_0+\frac{{\mathrm{SF}}_M^D}{R_M^D}+\frac{{\mathrm{SF}}_I^D}{R_I^D},$

delivery of the k¹ scrub description data is started with rate R^D if B_th(t)>R_vm(t). Here, R^D=R^D(T_I)−ΔR, & R^D(T_I)=B_th(T_I)−R_vm(T_I). Otherwise, at step 1760, bitrate adaptation is performed such that B_th(t)>R_vm(t). Then delivery of the k¹ layer of the scrub description file F^D(k¹) is started.

[0125] After completing the delivery of the k¹ layer of the scrub description file F^D(k¹), the next assigned layer (k^q) (q=2) of the scrub description file is sent if there is sufficient bandwidth (steps 1730 and 1740). In other words, at time t=T^D*(k^q-1)=T^D(k^q), delivery of the k^q scrub description data is started if B_th(t)>R_vm(t). Subsequent assigned layers of the scrub description (q=3, 4, . . . ) may be sent similarly. Otherwise, at step 1770, bitrate adaptation is performed such that B_th(t)>R_vm(t). Then delivery of the k^q layer of the scrub description file F^D(k^q) is started.

[0126] Similarly, when different degrees of the scrub descriptions are packed in different files, only the file that contains the first degree description shall be delivered while the higher degree ones are transported on demand or only when there is extra bandwidth.

[0127] In one or more embodiments, the preview description files may be saved in different server(s) instead of the original media. In this case, B_th(t) should be defined as the minimum available bandwidth between the media server and the client and that between the preview description server and the client.

[0128] A detailed description and sample embodiments for a PDR 330 (FIG. 11) will now be described using FIG. 17.

[0129] FIG. 17 illustrates a sample embodiment of a PDR 330 at a media player receiving preview data in accordance with an embodiment.

[0130] To ensure playback at any preview points without any glitch, alignment between the scrub description and the original media stream is needed. As discussed in the PDG section above, time segments Γ(i, k), which are registered in the index file, facilitate synchronization.

[0131] In the following sample embodiment, the scrub description data are packaged based on the location of the scrub description. That is, scrub description D(h, i, k) for hε[1, H] & iε[1, I_k] are packaged in the same file. H is the maximum degree of freedom as described above. I_k is the total number of scrub descriptions in layer k. Again, a person skilled in the art can easily modify the embodiment when all scrub description D(h, i, k) for Iε[1, I_k] and kE [1, K] are packaged into a single file or when for hε[1, H] are packaged in H different files.

[0132] Referring to FIG. 17, the media player receives the manifest file (step 1810). Next, the media player receives the index file (step 1820). If the scheduling algorithm described with respect to FIG. 15 is used, the media player downloads the 1^st layer preview file (step 1830). Subsequently, the media player downloads the k^th layer preview file (step 1840).

[0133] FIG. 18 illustrates a sample embodiment of a PDR 330 at a media player receiving preview data in accordance with an embodiment.

[0134] FIG. 18 illustrates a media player receiving preview data from a server using the PDD algorithm illustrated in FIG. 16 while FIG. 17 illustrates a media player receiving preview data from a server using the PDD algorithm illustrated in FIG. 15. Therefore, referring to FIG. 18, the Steps of 1810 and 1820 indicating the receipt of the manifest and index files remain the same as in the prior embodiment. Referring to Step 1910, k¹ layer preview file is received. Next, the media player downloads the k^q layer preview file. As described above, k¹, k^q layers are not delivered sequentially and may be selected using various criterion.

[0135] FIG. 19 illustrates a media player receiving preview data having multiple degrees of freedom in accordance with an embodiment of the invention.

[0136] Referring to FIG. 19, when the scrub description data with multiple degrees of freedom D(h,i,k) for hε[1,H] are packaged in different files, multiple files have to be downloaded. Accordingly, a first set of files are downloaded for the first degree of freedom. As in previous embodiments, the manifest file and the index file are received (Steps 1810 and 1820). Next, the first degree of the first layer preview data is received (Step 2010) following by the first degree of the k^th layer of the preview data (Step 2020).

[0137] At client's request or when additional bandwidth is detected (Step 2030), the media player starts to download the additional degree preview files in order from h=2 to h=H (Steps 2040 and 2050). The media player does not always need to download all the scrub description data files described in the manifest file. The number k may be decided based on user preference, the network conditions, the end to end available bandwidth and possibly other factors defined by the media player.

[0138] With a first layer scrub description data file, a user can get a coarse grain preview experience. After getting the following layers of scrub description data files, the user can enjoy finer grain preview experiences. In the meantime, with a first degree scrub description, a user gets some rough description and when additional descriptions are downloaded detailed description at each segment in each layer can be obtained.

[0139] For fast preview startup, the first layer scrub description data could be delivered before or right after the video starts to play back in various embodiments. Since the scrub description data is small by design, users can begin with the preview almost instantly. Based on user preference, the scrub description data might even be delivered before any of the original media data stream is being delivered. In this case, users can start browsing (preview) the story while the original media data stream is being buffered for playback. This is an alternative way to reduce user waiting time and hence improves the overall video access experience.

[0140] To facilitate instant playback from any scrub preview point D(i*, k), time segments Γ(1, k), Γ(2, k) . . . Γ(i*−1, k) are obtained from the index file. The end of all time segments available, which is the available preview length, be denoted as t*, which can be defined as

$t^{*}=\sum _{i=1}^{i^{*}-1}\Gamma \left(i,k\right).$

The available preview length t* is compared with the buffer. If the available preview length t* runs outside of the buffer, the media player may communicate with the edge server immediately to acquire the corresponding media segments from the original media data stream server to facilitate instant startup. Otherwise, the playback starts immediately at the original media segment that corresponds to t*.

[0141] Another possible embodiment of the stand-alone implementation takes advantage of the audio channel. That is, the scrub descriptions are played back in audio similar to a narrator instead of displayed as text. In this embodiment, still, multiple degrees and multiple layers of scrub previews can be facilitated and a skilled in the art can implement similar algorithms for PDG, PDD, and PDR.

[0142] Another embodiment that includes an add-on implementation will now be described. In this case, the scrub descriptions can be used as one or more added layers to the keyframe based scrub preview. In this embodiment, the scrub description data may be scheduled for delivery first with the first layer of the keyframes delivered next. For instance, the first layer of the preview keyframes can be scheduled for delivery at T^D*(K) or T^D*(K^Q) using similar algorithms as described in FIG. 15 or FIG. 16. When scrub descriptions are added as additional layers to the keyframe based scrub preview, the scrub description and the keyframe images may not need to be synchronized.

[0143] FIG. 20 illustrates a sample interface for a dual-view scrub preview in accordance with an embodiment of the invention. In this embodiment, both dual-view and toggled view can be realized using the dual view implementation. When a dual-view scrub preview is implemented, the preview keyframe and the corresponding scrub description text of a particular time frame of the video stream are displayed in a dual-view scrub preview window 61 as illustrated in FIG. 20. The dual-view scrub preview window 61 includes a scrub description text window 61a and a keyframe image 61b.

[0144] In various embodiments, the dual-view scrub preview window 61 may be configured differently in terms of the relative location of the scrub description text window 61a versus the location of the keyframe image 61b. For example, the user at the media player may configure the locations and view of the scrub description text window 61a and the keyframe image 61b. Embodiments of the present invention do not limit the type of configurations of the preview window.

[0145] In addition, in one or more embodiments, the description text for preview may be presented in audio format (in addition to or in place of the text format which is illustrated). The audio description has to start from the position where the playhead is moved to and paused at. In some embodiments, the preview images may be enhanced to be a series of short video clips which will auto-play when the playhead is scrubbed.

[0146] Often when video content is relatively long and the description texts are scattered along the progress bar, marker (range indicator 70, e.g., as illustrated in FIG. 20) may be introduced along the progress bar to facilitate the preview and content navigation efforts. In various embodiments, the description text can be tailored to country/region where the viewing is being requested so that correct language option can be made available (based on GPS, client location as seen from CDN, or user request from the media player).

[0147] In a toggled view scrub preview implementation, in one embodiment, either the keyframe image or the scrub description text/audio will be displayed in the scrub preview window. The view can be toggled from one type to the other using a hot key combination or other access method.

[0148] In the dual view scrub preview implementation, the scrub description may be synchronized with the keyframe images for ease of management and fast accessibility. That is, one keyframe KF(j,k) and one scrub description D(j, k) should be extracted from the same video segment Γ(j,k). Here, keyframe KF(j,k) and scrub description D(j, k), jε[1,J_k] denotes the keyframe and the corresponding scrub description of the jth segment Γ(j,k) in the kth layer preview. In contrast, the scrub description and the keyframe images need not be synchronized when scrub descriptions are added as additional layers to the keyframe based scrub preview.

[0149] Similar extraction schemes for scrub description D(j, k) described earlier, e.g., FIGS. 12-14, may be used in this embodiment. The keyframes KF(j,k) may be extracted using any suitable scheme known to one skilled in the art. For each layer, all keyframes KF(j,k)s and scrub description D(j, k)s for jε[1,J_k] may be packaged into a single dual view scrub data file F^DL(k) or packaged separately in various ways. In the following description, one single file per layer is used as an example. A single manifest file and a single index file may be generated for the entire preview data set that includes both the keyframes and the scrub descriptions in all layers.

[0150] For the preview delivery step, a slightly modified scheduling algorithm based on those described in FIGS. 15 and/or 16 may be employed. First, the manifest file and the index file are delivered. Then, the dual view scrub data file F^DL(k) may be delivered in a layer by layer fashion with the lower layers delivered first.

[0151] At the media player side, the media player may download the dual view scrub data file F^DL(k) after the manifest file and the index file are downloaded, starting from k=1. A toggled view or a dual-view scrub preview is achieved by displaying keyframes KF(j,k) and scrub data D(j, k) during the corresponding time frame F(j,k) in a toggled view or a dual-view fashion.

[0152] An embodiment of the invention describing the use of pertinent rich media scrub preview will now be described using FIG. 21. FIG. 21 illustrates a media player 50 rendering a media rich scrub preview window 62. In addition to the description data, it is possible to introduce other types of data or relevant information to facilitate additional scrub preview capabilities. For instance, when watching a sports game video, the users might be interested in information relevant to the sports teams or star players, recent game information, and possibly merchandize that is related to the type of sports, the game season, or the relevant teams. These and other relevant information can all serve as part of the database to generate the scrub preview. The scrub preview may be presented in a rich media format with video, image, graph, text, and any other type of media data incorporated into a single media rich scrub preview window 62 to provide preview and browsing services. A person skilled in the art can easily modify the generation, delivery, and rendering schemes discussed above in other embodiments and optimize it for this embodiment.

[0153] In yet another embodiment of the present invention, an independent preview service can be offered. Any user can subscribe to the preview service with or without the subscription to the VoD or real time video delivery service. A user subscribed to the preview service can be connected directly to the preview server at her request. The server shall deliver the preview content to the user based on her subscriber service class, the user profile, the network and device condition, etc. In this embodiment, the preview service server maybe connected to multiple video delivery servers that are part of a single or multiple IP video delivery service providers. The generic architecture of such a system may be implemented as illustrated in FIG. 10.

[0154] FIG. 22 illustrates a preview generation unit in accordance with embodiments of the invention. The preview generation unit may be the PG 10 (FIG. 1) or the PDG 310 (FIG. 11) in various embodiments. Referring to FIG. 22, a preview generation unit 2210 comprises a preview data generator 2220 configured to generate a preview data. The preview data generator 2220 comprises a preview data extractor 2230 configured to extract preview information from a media file to be streamed. The preview data generator 2220 is configured to generate a preview data that has a multi-dimensional hierarchical data structure having a plurality of layers. The content of the preview information in each layer increases in moving upto higher layers of the plurality of layers. The preview data generator 2220 is configured to provide a differentiated preview service.

[0155] FIG. 23 illustrates a preview delivery unit in accordance with embodiments of the invention. The preview delivery unit may be the PD 20 (FIG. 1) or the PDD 320 (FIG. 11) in various embodiments. Referring to FIG. 23, a preview delivery unit 2310 comprises a preview data transmitter 2320 configured to send a preview data comprising preview information from a media file to be streamed. The preview data transmitter 2320 is configured to send a multi-dimensional hierarchical data structure having a plurality of layers, e.g., stored in a single or a plurality of files in a non-transitory non-volatile storage medium. The content of the preview information in each layer increases in moving up to higher layers of the plurality of layers. The preview data transmitter 2320 is configured to provide a differentiated preview service.

[0156] FIG. 24 illustrates a preview receiver unit in accordance with embodiments of the invention. The preview receiver unit may be the PR 30 (FIG. 1) or the PDR 330 (FIG. 11) in various embodiments. Referring to FIG. 24, a preview receiver unit 2410 comprises a user data transmitter 2420 configured to send a preview data request to a preview server. The preview data request comprises a request for preview data. The preview receiver unit 2410 further comprises a media player receiver 2430 configured to receive a preview data comprising preview information. The received preview data comprises a multi-dimensional hierarchical data structure having a plurality of layers with increasing content of the preview information in each layer of the plurality of layers.

[0157] FIG. 25 illustrates a representative a preview server in accordance with embodiments of the invention.

[0158] The preview server 2500 includes a receiver 2510, which may include a wireless antenna receiver and/or a wired network connection port for receiving the media content, for example, if it is stored at a remote location. The preview server 2500 also includes a memory 2530, which may include both a non-volatile memory and a volatile memory. In one embodiment, instructions for performing the operations described with respect to FIGS. 1, 8, 9, 11, 12, 15-16 may be stored in a non-transitory storage medium such as a magnetic storage medium or a solid state storage medium in the memory 2530.

[0159] The preview server 2500 may include further I/O devices 2550 for inputting and outputting data. For example, the I/O devices 2550 may include an optical disc such as a laser readable medium, for example, a compact disc reader, a blue ray disk reader, and/or digital video reader etc. In one or more embodiments, the instructions for performing the operations as described in FIGS. 1, 8, 9, 11, 12, 15-16 may be stored in an optical disc, which is a non-transitory storage medium.

[0160] The preview server 2500 may also include a display 2560 and a transmitter 2540 for transmitting the preview data. The transmitter 2540 may include plurality of wireless antennas and/or a wired port. The transmitter 2540 and the receiver 2510 can be combined together in some embodiments.

[0161] The preview server 2500 includes a processor 2520 configured to execute the instructions for performing the operations described with respect to FIGS. 1, 8, 9, 11, 12, 15-16 as well as FIGS. 22 and 23. The processor 2520 may comprise a single processor or a plurality of processors.

[0162] FIG. 26 illustrates a representative a media player in accordance with embodiments of the invention.

[0163] The media player 2600 includes a media player (MP) receiver 2610, which may include a wireless antenna receiver and/or a wired network connection port for receiving the media content, for example, if it is stored at a remote location. The MP receiver 2610 may be used by the media player 2600 to receive the preview data files. The media player 2600 also includes a MP memory 2630, which may include both a non-volatile memory and a volatile memory. In one embodiment, instructions for performing the operations described with respect to FIGS. 1, 10-11, 17-19, and 24 may be stored in a non-transitory storage medium such as a magnetic storage medium or a solid state storage medium in the MP memory 2630.

[0164] The media player 2600 may include further MP I/O devices 2650 for inputting and outputting data. For example, the MP I/O devices 2650 may include an optical disc such as a laser readable medium, for example, a compact disc reader, a blue ray disk reader, and/or digital video reader etc. In one or more embodiments, the instructions for performing the operations as described in FIGS. 1, 10-11, 17-19, and 24 may be stored in an optical disc, which is a non-transitory storage medium.

[0165] The media player 2600 may also include a MP display 2560 and a MP transmitter 2540 for transmitting the user specified parameter data. The MP transmitter 2640 may include plurality of wireless antennas and/or a wired port. The MP transmitter 2640 and the MP receiver 2610 can be combined together in some embodiments.

[0166] The media player 2600 includes a MP processor 2620 configured to execute the instructions for performing the operations described with respect to FIGS. 1, 10, 11, 17-19, as well as FIGS. 24. The MP processor 2620 may comprise a single processor or a plurality of processors.

[0167] FIG. 27 illustrates a generic architecture of a system implementing the differentiated scrub preview in accordance with embodiments of the invention.

[0168] Referring to FIG. 27, a plurality of video servers 2720 may be serving a media stream to a client 2730. Upon request, a preview server 2710 may serve the client 2730 with a preview data stream. In various embodiments, the preview server 2710 may be a standalone server or may be part of a video server 2720.

[0169] Although not specifically disclosed, embodiments of the invention can be combined. For examples, embodiments described with respect to FIGS. 8-10 may be combined with the embodiments described with respect to FIGS. 11-21. For example, an integrated data structure may include both preview data type and scrub description data as different dimensions in one or more embodiments.

[0170] A number of features and advantages can be obtained from various embodiments of the invention. For example, in one aspect, the invention provides a system for description based scrub preview generation, delivery, and presentation via an online media player to facilitate fast scrub preview even when the network bandwidth is low. In another aspect, an on-demand video preview method that allows user to browse the video content, even the portion that is not currently buffered and to start browsing instantly on any terminal device and almost under any network condition including networks with very low bandwidth and/or frequent bandwidth fluctuations. This feature offers an informed viewing experience and provides convenient video browsing and searching capability with a natural drag and play functionality. In another aspect, a set of schemes for dual view preview generation, delivery, and presentation which offers both dual-view and toggled view scrub preview functionality is provided. In yet another aspect, a layered scrub description data structure, a synchronization scheme, along with a delivery scheme for fast preview startup while offering personalized preview experience is provided.

[0171] In a further aspect, a multi-degree scrub preview scheme to facilitate instant preview startup and personalized preview services is provided. In yet a further aspect, two delivery scheduling schemes can be configured for delivery at various optimal time points to minimize startup delay and playback jitter and/or configured for personalized delivery. In another aspect, a personalized description based scrub preview presentation scheduling scheme offers an alternative functionality to reduce user wait time at start up.

[0172] Embodiments of the present invention extend the scrub preview to provide ultra-fast preview startup functionality. In one or more embodiments, description based scrub preview are offered instead of keyframe based scrub preview. The preview can start instantly without affecting the playback of the video, even in very low bandwidth network conditions. In a separate embodiment, the present invention describes the systems and scheme to achieve an additional scrub preview style called dual view scrub preview that takes advantage of both the description based and the keyframe based scrub preview. The dual view scrub preview offers additional personalized service capability. Embodiments of the present invention address the system and method to realize the description based scrub preview as well as the dual view scrub previews in a networked media distribution system with an online media player.

[0173] While this invention has been described with reference to illustrative embodiments, this description is not intended to be construed in a limiting sense. Various modifications and combinations of the illustrative embodiments, as well as other embodiments of the invention, will be apparent to persons skilled in the art upon reference to the description. It is therefore intended that the appended claims encompass any such modifications or embodiments.

[0174] Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. For example, many of the features and functions discussed above can be implemented in software, hardware, or firmware, or a combination thereof.

[0175] Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed, that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.