12,594 research outputs found
Saying What You're Looking For: Linguistics Meets Video Search
We present an approach to searching large video corpora for video clips which
depict a natural-language query in the form of a sentence. This approach uses
compositional semantics to encode subtle meaning that is lost in other systems,
such as the difference between two sentences which have identical words but
entirely different meaning: "The person rode the horse} vs. \emph{The horse
rode the person". Given a video-sentence pair and a natural-language parser,
along with a grammar that describes the space of sentential queries, we produce
a score which indicates how well the video depicts the sentence. We produce
such a score for each video clip in a corpus and return a ranked list of clips.
Furthermore, this approach addresses two fundamental problems simultaneously:
detecting and tracking objects, and recognizing whether those tracks depict the
query. Because both tracking and object detection are unreliable, this uses
knowledge about the intended sentential query to focus the tracker on the
relevant participants and ensures that the resulting tracks are described by
the sentential query. While earlier work was limited to single-word queries
which correspond to either verbs or nouns, we show how one can search for
complex queries which contain multiple phrases, such as prepositional phrases,
and modifiers, such as adverbs. We demonstrate this approach by searching for
141 queries involving people and horses interacting with each other in 10
full-length Hollywood movies.Comment: 13 pages, 8 figure
Multi-grained Temporal Prototype Learning for Few-shot Video Object Segmentation
Few-Shot Video Object Segmentation (FSVOS) aims to segment objects in a query
video with the same category defined by a few annotated support images.
However, this task was seldom explored. In this work, based on IPMT, a
state-of-the-art few-shot image segmentation method that combines external
support guidance information with adaptive query guidance cues, we propose to
leverage multi-grained temporal guidance information for handling the temporal
correlation nature of video data. We decompose the query video information into
a clip prototype and a memory prototype for capturing local and long-term
internal temporal guidance, respectively. Frame prototypes are further used for
each frame independently to handle fine-grained adaptive guidance and enable
bidirectional clip-frame prototype communication. To reduce the influence of
noisy memory, we propose to leverage the structural similarity relation among
different predicted regions and the support for selecting reliable memory
frames. Furthermore, a new segmentation loss is also proposed to enhance the
category discriminability of the learned prototypes. Experimental results
demonstrate that our proposed video IPMT model significantly outperforms
previous models on two benchmark datasets. Code is available at
https://github.com/nankepan/VIPMT.Comment: ICCV 202
Grounding spatial prepositions for video search
Spatial language video retrieval is an important real-world problem that forms a test bed for evaluating semantic structures for natural language descriptions of motion on naturalistic data. Video search by natural language query requires that linguistic input be converted into structures that operate on video in order to find clips that match a query. This paper describes a framework for grounding the meaning of spatial prepositions in video. We present a library of features that can be used to automatically classify a video clip based on whether it matches a natural language query. To evaluate these features, we collected a corpus of natural language descriptions about the motion of people in video clips. We characterize the language used in the corpus, and use it to train and test models for the meanings of the spatial prepositions "to," "across," "through," "out," "along," "towards," and "around." The classifiers can be used to build a spatial language video retrieval system that finds clips matching queries such as "across the kitchen."United States. Office of Naval Research (MURI N00014-07-1-0749
QUERY CLIP GENRE RECOGNITION USING TREE PRUNING TECHNIQUE FOR VIDEO RETRIEVAL
ABSTRACT Optimal efficiency of the retrieval techniques depends on the search methodologies that are used in the data retrieving system. The use of inappropriate search methodologies may make the retrieval system ineffective. In recent years, the multimedia storage grows and the cost for storing multimedia data is cheaper. So there is huge number of videos available in the video repositories. It is difficult to retrieve the relevant videos from large video repository as per user interest. Hence, an effective video and retrieval system based on recognition is essential for searching video relevant to user query from a huge collection of videos. An approach, which retrieves video from repository by recognizing genre of user query clip is presented. The method extracts regions of interest from every frame of query clip based on motion descriptors. These regions of interest are considered as objects and are compared with similar objects from knowledge base prepared from various genre videos for object recognition and a tree pruning technique is employed to do genre recognition of query clip. Further the method retrieves videos of same genre from repository. The method is evaluated by experimentation over data set containing three genres i.e. sports movie and news videos. Experimental results indicate that the proposed algorithm is effective in genre recognition and retrieval
Generation-Guided Multi-Level Unified Network for Video Grounding
Video grounding aims to locate the timestamps best matching the query
description within an untrimmed video. Prevalent methods can be divided into
moment-level and clip-level frameworks. Moment-level approaches directly
predict the probability of each transient moment to be the boundary in a global
perspective, and they usually perform better in coarse grounding. On the other
hand, clip-level ones aggregate the moments in different time windows into
proposals and then deduce the most similar one, leading to its advantage in
fine-grained grounding. In this paper, we propose a multi-level unified
framework to enhance performance by leveraging the merits of both moment-level
and clip-level methods. Moreover, a novel generation-guided paradigm in both
levels is adopted. It introduces a multi-modal generator to produce the
implicit boundary feature and clip feature, later regarded as queries to
calculate the boundary scores by a discriminator. The generation-guided
solution enhances video grounding from a two-unique-modals' match task to a
cross-modal attention task, which steps out of the previous framework and
obtains notable gains. The proposed Generation-guided Multi-level Unified
network (GMU) surpasses previous methods and reaches State-Of-The-Art on
various benchmarks with disparate features, e.g., Charades-STA, ActivityNet
captions
- …