24 research outputs found
Video Fill In the Blank using LR/RL LSTMs with Spatial-Temporal Attentions
Given a video and a description sentence with one missing word (we call it
the "source sentence"), Video-Fill-In-the-Blank (VFIB) problem is to find the
missing word automatically. The contextual information of the sentence, as well
as visual cues from the video, are important to infer the missing word
accurately. Since the source sentence is broken into two fragments: the
sentence's left fragment (before the blank) and the sentence's right fragment
(after the blank), traditional Recurrent Neural Networks cannot encode this
structure accurately because of many possible variations of the missing word in
terms of the location and type of the word in the source sentence. For example,
a missing word can be the first word or be in the middle of the sentence and it
can be a verb or an adjective. In this paper, we propose a framework to tackle
the textual encoding: Two separate LSTMs (the LR and RL LSTMs) are employed to
encode the left and right sentence fragments and a novel structure is
introduced to combine each fragment with an "external memory" corresponding the
opposite fragments. For the visual encoding, end-to-end spatial and temporal
attention models are employed to select discriminative visual representations
to find the missing word. In the experiments, we demonstrate the superior
performance of the proposed method on challenging VFIB problem. Furthermore, we
introduce an extended and more generalized version of VFIB, which is not
limited to a single blank. Our experiments indicate the generalization
capability of our method in dealing with such more realistic scenarios
Learning Fashion Compatibility with Bidirectional LSTMs
The ubiquity of online fashion shopping demands effective recommendation
services for customers. In this paper, we study two types of fashion
recommendation: (i) suggesting an item that matches existing components in a
set to form a stylish outfit (a collection of fashion items), and (ii)
generating an outfit with multimodal (images/text) specifications from a user.
To this end, we propose to jointly learn a visual-semantic embedding and the
compatibility relationships among fashion items in an end-to-end fashion. More
specifically, we consider a fashion outfit to be a sequence (usually from top
to bottom and then accessories) and each item in the outfit as a time step.
Given the fashion items in an outfit, we train a bidirectional LSTM (Bi-LSTM)
model to sequentially predict the next item conditioned on previous ones to
learn their compatibility relationships. Further, we learn a visual-semantic
space by regressing image features to their semantic representations aiming to
inject attribute and category information as a regularization for training the
LSTM. The trained network can not only perform the aforementioned
recommendations effectively but also predict the compatibility of a given
outfit. We conduct extensive experiments on our newly collected Polyvore
dataset, and the results provide strong qualitative and quantitative evidence
that our framework outperforms alternative methods.Comment: ACM MM 1
KnowIT VQA: Answering Knowledge-Based Questions about Videos
We propose a novel video understanding task by fusing knowledge-based and
video question answering. First, we introduce KnowIT VQA, a video dataset with
24,282 human-generated question-answer pairs about a popular sitcom. The
dataset combines visual, textual and temporal coherence reasoning together with
knowledge-based questions, which need of the experience obtained from the
viewing of the series to be answered. Second, we propose a video understanding
model by combining the visual and textual video content with specific knowledge
about the show. Our main findings are: (i) the incorporation of knowledge
produces outstanding improvements for VQA in video, and (ii) the performance on
KnowIT VQA still lags well behind human accuracy, indicating its usefulness for
studying current video modelling limitations