The ability to map descriptions of scenes to 3D geometric representations has many applications in areas such as art, education, and robotics. However, prior work on the text to 3D scene generation task has used manually specified object categories and language that identifies them. We introduce a dataset of 3D scenes annotated with natural language descriptions and learn from this data how to ground textual descriptions to physical objects. Our method successfully grounds a variety of lexical terms to concrete referents, and we show quantitatively that our method improves 3D scene generation over previous work using purely rule-based methods. We evaluate the fidelity and plausibility of 3D scenes generated with our grounding approach through human judgments. To ease evaluation on this task, we also introduce an automated metric that strongly correlates with human judgments.
A related line of work focuses on grounding referring expressions to referents in 3D worlds with simple colored geometric shapes @cite_5 @cite_4 . More recent work grounds text to object attributes such as color and shape in images @cite_2 @cite_9 . ground spatial relationship language in 3D scenes (e.g., to the left of , behind ) by learning from pairwise object relations provided by crowd-workers. In contrast, we ground general descriptions to a wide variety of possible objects. The objects in our scenes represent a broader space of possible referents than the first two lines of work. Unlike the latter work, our descriptions are provided as unrestricted free-form text, rather than filling in specific templates of object references and fixed spatial relationships.
@cite_5 @cite_9 @cite_4 @cite_2
2111807093 2186283982 2140164026 2949559657
We present a visually-grounded language understanding model based on a study of how people verbally describe objects in scenes. The emphasis of the model is on the combination of individual word meanings to produce meanings for complex referring expressions. The model has been implemented, and it is able to understand a broad range of spatial referring expressions. We describe our implementation of word level visually-grounded semantics and their embedding in a compositional parsing framework. The implemented system selects the correct referents in response to natural language expressions for a large percentage of test cases. In an analysis of the system's successes and failures we reveal how visual context influences the semantics of utterances and propose future extensions to the model that take such context into account. This paper introduces Logical Semantics with Perception (LSP), a model for grounded language acquisition that learns to map natural language statements to their referents in a physical environment. For example, given an image, LSP can map the statement “blue mug on the table” to the set of image segments showing blue mugs on tables. LSP learns physical representations for both categorical (“blue,” “mug”) and relational (“on”) language, and also learns to compose these representations to produce the referents of entire statements. We further introduce a weakly supervised training procedure that estimates LSP’s parameters using annotated referents for entire statements, without annotated referents for individual words or the parse structure of the statement. We perform experiments on two applications: scene understanding and geographical question answering. We find that LSP outperforms existing, less expressive models that cannot represent relational language. We further find that weakly supervised training is competitive with fully supervised training while requiring significantly less annotation effort. Situated, spontaneous speech may be ambiguous along acoustic, lexical, grammatical and semantic dimensions. To understand such a seemingly difficult signal, we propose to model the ambiguity inherent in acoustic signals and in lexical and grammatical choices using compact, probabilistic representations of multiple hypotheses. To resolve semantic ambiguities we propose a situation model that captures aspects of the physical context of an utterance as well as the speaker's intentions, in our case represented by recognized plans. In a single, coherent Framework for Understanding Situated Speech (FUSS) we show how these two influences, acting on an ambiguous representation of the speech signal, complement each other to disambiguate form and content of situated speech. This method produces promising results in a game playing environment and leaves room for other types of situation models. As robots become more ubiquitous and capable, it becomes ever more important to enable untrained users to easily interact with them. Recently, this has led to study of the language grounding problem, where the goal is to extract representations of the meanings of natural language tied to perception and actuation in the physical world. In this paper, we present an approach for joint learning of language and perception models for grounded attribute induction. Our perception model includes attribute classifiers, for example to detect object color and shape, and the language model is based on a probabilistic categorial grammar that enables the construction of rich, compositional meaning representations. The approach is evaluated on the task of interpreting sentences that describe sets of objects in a physical workspace. We demonstrate accurate task performance and effective latent-variable concept induction in physical grounded scenes.