Gupta, Sonal
Make-An-Animation: Large-Scale Text-conditional 3D Human Motion Generation
Azadi, Samaneh, Shah, Akbar, Hayes, Thomas, Parikh, Devi, Gupta, Sonal
Text-guided human motion generation has drawn significant interest because of its impactful applications spanning animation and robotics. Recently, application of diffusion models for motion generation has enabled improvements in the quality of generated motions. However, existing approaches are limited by their reliance on relatively small-scale motion capture data, leading to poor performance on more diverse, in-the-wild prompts. In this paper, we introduce Make-An-Animation, a text-conditioned human motion generation model which learns more diverse poses and prompts from large-scale image-text datasets, enabling significant improvement in performance over prior works. Make-An-Animation is trained in two stages. First, we train on a curated large-scale dataset of (text, static pseudo-pose) pairs extracted from image-text datasets. Second, we fine-tune on motion capture data, adding additional layers to model the temporal dimension. Unlike prior diffusion models for motion generation, Make-An-Animation uses a U-Net architecture similar to recent text-to-video generation models. Human evaluation of motion realism and alignment with input text shows that our model reaches state-of-the-art performance on text-to-motion generation.
Text-Conditional Contextualized Avatars For Zero-Shot Personalization
Azadi, Samaneh, Hayes, Thomas, Shah, Akbar, Pang, Guan, Parikh, Devi, Gupta, Sonal
Recent large-scale text-to-image generation models have made significant improvements in the quality, realism, and diversity of the synthesized images and enable users to control the created content through language. However, the personalization aspect of these generative models is still challenging and under-explored. In this work, we propose a pipeline that enables personalization of image generation with avatars capturing a user's identity in a delightful way. Our pipeline is zero-shot, avatar texture and style agnostic, and does not require training on the avatar at all - it is scalable to millions of users who can generate a scene with their avatar. To render the avatar in a pose faithful to the given text prompt, we propose a novel text-to-3D pose diffusion model trained on a curated large-scale dataset of in-the-wild human poses improving the performance of the SOTA text-to-motion models significantly. We show, for the first time, how to leverage large-scale image datasets to learn human 3D pose parameters and overcome the limitations of motion capture datasets.
SpaText: Spatio-Textual Representation for Controllable Image Generation
Avrahami, Omri, Hayes, Thomas, Gafni, Oran, Gupta, Sonal, Taigman, Yaniv, Parikh, Devi, Lischinski, Dani, Fried, Ohad, Yin, Xi
Recent text-to-image diffusion models are able to generate convincing results of unprecedented quality. However, it is nearly impossible to control the shapes of different regions/objects or their layout in a fine-grained fashion. Previous attempts to provide such controls were hindered by their reliance on a fixed set of labels. To this end, we present SpaText - a new method for text-to-image generation using open-vocabulary scene control. In addition to a global text prompt that describes the entire scene, the user provides a segmentation map where each region of interest is annotated by a free-form natural language description. Due to lack of large-scale datasets that have a detailed textual description for each region in the image, we choose to leverage the current large-scale text-to-image datasets and base our approach on a novel CLIP-based spatio-textual representation, and show its effectiveness on two state-of-the-art diffusion models: pixel-based and latent-based. In addition, we show how to extend the classifier-free guidance method in diffusion models to the multi-conditional case and present an alternative accelerated inference algorithm. Finally, we offer several automatic evaluation metrics and use them, in addition to FID scores and a user study, to evaluate our method and show that it achieves state-of-the-art results on image generation with free-form textual scene control.
El Volumen Louder Por Favor: Code-switching in Task-oriented Semantic Parsing
Einolghozati, Arash, Arora, Abhinav, Lecanda, Lorena Sainz-Maza, Kumar, Anuj, Gupta, Sonal
Being able to parse code-switched (CS) utterances, such as Spanish+English or Hindi+English, is essential to democratize task-oriented semantic parsing systems for certain locales. In this work, we focus on Spanglish (Spanish+English) and release a dataset, CSTOP, containing 5800 CS utterances alongside their semantic parses. We examine the CS generalizability of various Cross-lingual (XL) models and exhibit the advantage of pre-trained XL language models when data for only one language is present. As such, we focus on improving the pre-trained models for the case when only English corpus alongside either zero or a few CS training instances are available. We propose two data augmentation methods for the zero-shot and the few-shot settings: fine-tune using translate-and-align and augment using a generation model followed by match-and-filter. Combining the few-shot setting with the above improvements decreases the initial 30-point accuracy gap between the zero-shot and the full-data settings by two thirds.
NeurIPS 2020 EfficientQA Competition: Systems, Analyses and Lessons Learned
Min, Sewon, Boyd-Graber, Jordan, Alberti, Chris, Chen, Danqi, Choi, Eunsol, Collins, Michael, Guu, Kelvin, Hajishirzi, Hannaneh, Lee, Kenton, Palomaki, Jennimaria, Raffel, Colin, Roberts, Adam, Kwiatkowski, Tom, Lewis, Patrick, Wu, Yuxiang, Kรผttler, Heinrich, Liu, Linqing, Minervini, Pasquale, Stenetorp, Pontus, Riedel, Sebastian, Yang, Sohee, Seo, Minjoon, Izacard, Gautier, Petroni, Fabio, Hosseini, Lucas, De Cao, Nicola, Grave, Edouard, Yamada, Ikuya, Shimaoka, Sonse, Suzuki, Masatoshi, Miyawaki, Shumpei, Sato, Shun, Takahashi, Ryo, Suzuki, Jun, Fajcik, Martin, Docekal, Martin, Ondrej, Karel, Smrz, Pavel, Cheng, Hao, Shen, Yelong, Liu, Xiaodong, He, Pengcheng, Chen, Weizhu, Gao, Jianfeng, Oguz, Barlas, Chen, Xilun, Karpukhin, Vladimir, Peshterliev, Stan, Okhonko, Dmytro, Schlichtkrull, Michael, Gupta, Sonal, Mehdad, Yashar, Yih, Wen-tau
We review the EfficientQA competition from NeurIPS 2020. The competition focused on open-domain question answering (QA), where systems take natural language questions as input and return natural language answers. The aim of the competition was to build systems that can predict correct answers while also satisfying strict on-disk memory budgets. These memory budgets were designed to encourage contestants to explore the trade-off between storing large, redundant, retrieval corpora or the parameters of large learned models. In this report, we describe the motivation and organization of the competition, review the best submissions, and analyze system predictions to inform a discussion of evaluation for open-domain QA.
Better Fine-Tuning by Reducing Representational Collapse
Aghajanyan, Armen, Shrivastava, Akshat, Gupta, Anchit, Goyal, Naman, Zettlemoyer, Luke, Gupta, Sonal
Although widely adopted, existing approaches for fine-tuning pre-trained language models have been shown to be unstable across hyper-parameter settings, motivating recent work on trust region methods. In this paper, we present a simplified and efficient method rooted in trust region theory that replaces previously used adversarial objectives with parametric noise (sampling from either a normal or uniform distribution), thereby discouraging representation change during fine-tuning when possible without hurting performance. We also introduce a new analysis to motivate the use of trust region methods more generally, by studying representational collapse; the degradation of generalizable representations from pre-trained models as they are fine-tuned for a specific end task. Extensive experiments show that our fine-tuning method matches or exceeds the performance of previous trust region methods on a range of understanding and generation tasks (including DailyMail/CNN, Gigaword, Reddit TIFU, and the GLUE benchmark), while also being much faster. We also show that it is less prone to representation collapse; the pre-trained models maintain more generalizable representations every time they are fine-tuned.
Improving Semantic Parsing for Task Oriented Dialog
Einolghozati, Arash, Pasupat, Panupong, Gupta, Sonal, Shah, Rushin, Mohit, Mrinal, Lewis, Mike, Zettlemoyer, Luke
Semantic parsing using hierarchical representations has recently been proposed for task oriented dialog with promising results [Gupta et al 2018]. In this paper, we present three different improvements to the model: contextualized embeddings, ensembling, and pairwise re-ranking based on a language model. We taxonomize the errors possible for the hierarchical representation, such as wrong top intent, missing spans or split spans, and show that the three approaches correct different kinds of errors. The best model combines the three techniques and gives 6.4% better exact match accuracy than the state-of-the-art, with an error reduction of 33%, resulting in a new state-of-the-art result on the Task Oriented Parsing (TOP) dataset.
Using Closed Captions as Supervision for Video Activity Recognition
Gupta, Sonal (Stanford University) | Mooney, Raymond J. (University of Texas at Austin)
Recognizing activities in real-world videos is a difficult problem exacerbated by background clutter, changes in camera angle & zoom, and rapid camera movements. Large corpora of labeled videos can be used to train automated activity recognition systems, but this requires expensive human labor and time. This paper explores how closed captions that naturally accompany many videos can act as weak supervision that allows automatically collecting "labeled" data for activity recognition. We show that such an approach can improve activity retrieval in soccer videos. Our system requires no manual labeling of video clips and needs minimal human supervision. We also present a novel caption classifier that uses additional linguistic information to determine whether a specific comment refers to an ongoing activity. We demonstrate that combining linguistic analysis and automatically trained activity recognizers can significantly improve the precision of video retrieval.