Abstract: An online distributed computer system with methodologies for distributed trace aggregation and targeting distributed tracing. In one aspect, the disclosed distributed tracing technologies improve on existing distributed tracing technologies by providing to application developers and site operations personnel a more holistic and comprehensive insight into the behavior of the online distributed computer system in the form of computed span metric aggregates displayed in a graphical user interface thereby making it easier for such personnel to diagnose problems in the system and to support and maintain the system. In another aspect, the disclosed distributed tracing technologies improve on existing distributed tracing technologies by facilitating targeted tracing of initiator requests.

Abstract: In various embodiments, a subsequence-based encoding application generates a convex hull of subsequence encode points based on multiple encoding points and a first subsequence included in a set of subsequences that are associated with a media title. The subsequence-based encoding application then generates a first encode list that includes multiple subsequence encode points based on the first convex hull. Notably, each subsequence encode point included in the first encode list is associated with a different subsequence. The subsequence-based encoding application selects a first subsequence encode point included in the first encode list based on a first variability constraint that is associated with a media metric. The subsequence-based encoding application then replaces the first subsequence encode point included in the first encode list with a second subsequence encode point to generate a second encode list.

Abstract: In various embodiments, a workflow engine executes a custom algorithm on a media item. In operation, the workflow engine generates split specifications based on a split function included in a container image. Each split specification is associated with a different portion of the media item. Subsequently, the workflow engine generates map output files based on the split specifications and a map function included in the container image. The workflow engine then generates one or more final output file(s) based on the map output files and a collect function included in the container image. The final output file(s) are subsequently used to perform at least one of an evaluation operation on, a modification operation on, and a representation operation with respect to the media item.

Abstract: One embodiment of the invention sets forth a mechanism for encoding video streams associated with the same digital content such that switch points staggered across two video streams occur at every offset temporal distance. The offset temporal distance is less than the distance between two consecutive key frames in a given video stream. This enables a content player to switch to a video stream having a playback quality up or down one level from a current video stream at the offset temporal distance from the most recently played key frame. In effect, the content player does not wait the entire key frame temporal distance before switching.

Abstract: One embodiment of the present invention sets forth a technique for testing microservices in distributed computing systems. The technique includes routing a first traffic sample associated with request traffic from one or more client devices to a first instance of a first service implemented in a distributed computing system, wherein the first instance generates a first plurality of request responses in response to a first plurality of data requests included in the first traffic sample and transmits the first plurality of request responses to a second service included in the sequence of services, and routing a second traffic sample associated with the request traffic to a second instance of the first service, wherein the second instance generates a second plurality of request responses in response to a second plurality of data requests included in the second traffic sample and transmits the second plurality of request responses to the second service.

Abstract: In various embodiments, a hindsight application computes a total download size for a sequence of encoded chunks associated with a media title for evaluation of at least one aspect of a video streaming service. The hindsight application computes a feasible download end time associated with a source chunk of the media title based on a network throughput trace and a subsequent feasible download end time associated with a subsequent source chunk of the media title. The hindsight application then selects an encoded chunk associated with the source chunk based on the network throughput trace, the feasible download end time, and a preceding download end time associated with a preceding source chunk of the media title. Subsequently, the hindsight application computes the total download size based on the number of encoded bits included in the first encoded chunk. The total download size correlates to an upper bound on visual quality.

Abstract: In various embodiments, a reconstruction application generates reconstructed video content that includes synthesized film grain. The reconstruction application performs scaling operation(s) on first unit noise based on a piecewise linear scaling function and the brightness component of the decoded video content to generate a brightness component of synthesized film grain. The reconstruction application then generates a brightness component of reconstructed video content based on the brightness component of the synthesized film grain and the brightness component of the decoded video content. Finally, the reconstructed application performs operation(s) related to saving the reconstructed video content to a file and/or further processing the reconstructed video content. Advantageously, the synthesized film grain reliably represents the film grain included in source video content from which the decoded video content was derived.

Abstract: In various embodiments, a subsequence-based encoding application generates a first set of subsequence encode points based on multiple encoding points and a first subsequence included in a set of subsequences that are associated with a media title. Notably, each subsequence encode point is associated with a different encoded subsequence. The subsequence-based encoding application then performs convex hull operation(s) across the first set of subsequence encode points to generate a first convex hull. The subsequence-based encoding application then generates an encode list that includes multiple subsequence encode points based on multiple convex hulls, including the first convex hull. Subsequently, the subsequence-based encoding application performs filtering operation(s) on the encode list based on a variability constraint associated with a media metric to generate an upgrade candidate list.

Abstract: The disclosed computer-implemented method may include receiving, as an input, segmented video scenes, where each video scene includes a specified length of video content. The method may further include scanning the video scenes to identify objects within the video scene and also determining a relative importance value for the identified objects. The relative importance value may include an indication of which objects are to be included in a cropped version of the video scene. The method may also include generating a video crop that is to be applied to the video scene such that the resulting cropped version of the video scene includes those identified objects that are to be included based on the relative importance value. The method may also include applying the generated video crop to the video scene to produce the cropped version of the video scene. Various other methods systems and computer-readable media are also disclosed.

Abstract: In various embodiments, a perceptual quality application determines an absolute quality score for encoded video content viewed on a target viewing device. In operation, the perceptual quality application determines a baseline absolute quality score for the encoded video content viewed on a baseline viewing device. Subsequently, the perceptual quality application determines that a target value for a type of the target viewing device does not match a base value for the type of the baseline viewing device. The perceptual quality application computes an absolute quality score for the encoded video content viewed on the target viewing device based on the baseline absolute quality score and the target value. Because the absolute quality score is independent of the viewing device, the absolute quality score accurately reflects the perceived quality of a wide range of encoded video content when decoded and viewed on a viewing device.

Abstract: In various embodiments, a quality trainer trains a model that computes a value for a perceptual video quality metric for encoded video content. During a pre-training phase, the quality trainer partitions baseline values for metrics that describe baseline encoded video content into partitions based on genre. The quality trainer then performs cross-validation operations on the partitions to optimize hyperparameters associated with the model. Subsequently, during a training phase, the quality trainer performs training operations on the model that includes the optimized hyperparameters based on the baseline values for the metrics to generate a trained model. The trained model accurately tracks the video quality for the baseline encoded video content. Further, because the cross-validation operations minimize any potential overfitting, the trained model accurately and consistently predicts perceived video quality for non-baseline encoded video content across a wide range of genres.

Abstract: In various embodiments, a subtitle timing application detects timing errors between subtitles and shot changes. In operation, the subtitle timing application determines that a temporal edge associated with a subtitle does not satisfy a timing guideline based on a shot change. The shot change occurs within a sequence of frames of an audiovisual program. The subtitle timing application then determines a new temporal edge that satisfies the timing guideline relative to the shot change. Subsequently, the subtitle timing application causes a modification to a temporal location of the subtitle within the sequence of frames based on the new temporal edge. Advantageously, the modification to the subtitle improves a quality of a viewing experience for a viewer. Notably, by automatically detecting timing errors, the subtitle timing application facilitates proper and efficient re-scheduling of subtitles that are not optimally timed with shot changes.

Abstract: Techniques are disclosed for reclaiming resources within a distributed computing system. A reclamation application searches the distributed computing architecture for unused resources, classifies the unused resources, and determines an expiration period based on the classification. The reclamation application determines a candidate owner of the resource based on one or more characteristics of the resource. The reclamation application then notifies the candidate owner that the resource is to be reclaimed unless claimed by the candidate owner within the expiration period. If the candidate owner claims the resource within the expiration period, then the reclamation application terminates the reclamation of the resource. If the candidate owner does not claim the resource within the expiration period, then the reclamation application reclaims the resource after the duration of the expiration period.

Abstract: In various embodiments, a perceptual quality application computes an absolute quality score for encoded video content. In operation, the perceptual quality application selects a model based on the spatial resolution of the video content from which the encoded video content is derived. The model associates a set of objective values for a set of objective quality metrics with an absolute quality score. The perceptual quality application determines a set of target objective values for the objective quality metrics based on the encoded video content. Subsequently, the perceptual quality application computes the absolute quality score for the encoded video content based on the selected model and the set of target objective values. Because the absolute quality score is independent of the quality of the video content, the absolute quality score accurately reflects the perceived quality of a wide range of encoded video content when decoded and viewed.

Abstract: One embodiment of the present invention sets forth a technique for compressing a forwarding table. The technique includes selecting, from a listing of network prefixes, a plurality of network prefixes that are within a range of a subnet. The technique further includes sorting the plurality of network prefixes to generate one or more subgroups of network prefixes and selecting a first subgroup of network prefixes included in the one or more subgroups of network prefixes. The technique further includes generating a synthetic supernet based on the first subgroup of network prefixes.

Abstract: A playback application seamlessly advances playback of and interactive media title in response to user selections in a manner that minimizes latency and preserves user immersion in a narrative. The playback application buffers an interstitial segment included in the interactive media title and feeds portions of the interstitial segment to a media player only when those portions are needed for display. When the user selects an option displayed during the interstitial segment, the playback application begins buffering a subsequent media segment and stops feeding portions of the interstitial segment to the media player. The playback application starts feeding blocks of the subsequent media segment to the media player and then seamlessly advances playback to the subsequent media segment.

Abstract: A method and system for discovering and testing security assets is provided. Based on source definition data describing sources to monitor on the one or more computer networks, an example system scans the sources to identify security assets. The system analyses the security assets to identify characteristics of the server-based applications. The system stores database records describing the security assets and the identified characteristics. The system queries the database records to select, based at least on the identified characteristics, one or more target assets, from the security assets, on which to conduct one or more security tests. Responsive to selecting the one or more target assets, the system conducts the one or more security tests on the one or more target assets. The system identifies one or more security vulnerabilities at the one or more target assets based on the conducted one or more security tests.

Abstract: Techniques for activity information schema discovery, schema change detection, and notification. In one embodiment, for example, a computer-implemented method for activity information schema discovery and schema change detection and notification comprises: analyzing a first set of related activity messages obtained during a first sample period; determining first schema counters for uniquely named properties identified in the first set of messages based on the analyzing of the first set of activity messages; after the first sample period, inferring a first schema from the first schema counters; analyzing a second set of related activity messages obtained during a second sample period; determining second schema counters for uniquely named properties identified in the second set of messages based on the analyzing of the second set of activity messages; after the second sample period, inferring a second schema from the second schema counters; comparing the first schema and the second schema for any differences.

Abstract: In various embodiments, a node manager configures a “new” node as a replacement for an “unavailable” node that was previously included in a distributed data store. First, the node manager identifies a source node that stores client data that was also stored in the unavailable node. Subsequently, the node manager configures the new node to operate as a slave of the source node and streams the client data from the source node to the new node. Finally, the node manager configures the new node to operate as one of multiple masters nodes in the distributed data store. Advantageously, by configuring the node to implement a hybrid of a master-slave replication scheme and a master-master replication scheme, the node manager enables the distributed data store to process client requests without interruption while automatically restoring the previous level of redundancy provided by the distributed data store.