Tag Archives: Research

New Solutions for Quantum Gravity with TensorFlow



Recent strides in machine learning (ML) research have led to the development of tools useful for research problems well beyond the realm for which they were designed. The value of these tools when applied to topics ranging from teaching robots how to throw to predicting the olfactory properties of molecules is now beginning to be realized. Inspired by advances such as these, we undertook the challenge of applying TensorFlow, a computing platform normally used for ML, to advance the understanding of fundamental physics.

Perhaps the biggest open problem in fundamental theoretical physics may be that our current understanding of quantum mechanics only includes three of the four fundamental forces — the electromagnetic, strong, and weak forces. There is currently no complete quantum theory that also includes the force of gravitation, while still matching experimental observations, i.e., an accurate model of quantum gravity.

One promising approach to a unified model that includes quantum gravity, which has survived many mathematical consistency checks, is called M-Theory, or "The Theory formerly known as Strings,” introduced in 1995 by Edward Witten. In the everyday world, we all experience four dimensions—three spatial dimensions (x, y, and z), plus time (t). M-Theory predicts that, at very short lengths, the Universe is described, instead, by eleven dimensions. But, as one can imagine, establishing the connection between the four-dimensional world that we observe and the 11-dimensional world predicted by M-theory is exceedingly difficult to solve analytically. In fact, it might require analytic manipulation of equations having more terms than there are electrons in the Universe.

This summer, we published an article in the Journal of High Energy Physics where we introduced novel ways to address such problems through creative use of ML technology. Using simplifications enabled by TensorFlow, we managed to bring the total number of known (stable or unstable) equilibrium solutions for one particular type of M-Theory spacetime geometries to 194, including a new and tachyon-free four-dimensional model universe. The geometries that we studied are special in that they are still (barely) accessible with exact calculations that do not require neglecting potentially important terms. We have also released a short instructive Google colab as well as a more powerful Python library for use in related research.

Applying TensorFlow to M-Theory
This work is predicated on a key observation that a mixed numerical and analytic approach can be more powerful than a purely analytical method. Instead of attempting to find analytic solutions with brute force, we use a numerical approach that leverages TensorFlow for the initial search for solutions to the model. This then yields hypotheses on which specific combinations can be tested and analyzed with stringent mathematical methods, ultimately proving the actual existence of a conjectured solution. This represents a novel methodology for making further progress in theoretical physics.

Conclusion
We hope that these results will be an important step in interpreting M-theory, and demonstrate how the research community can use new ML tools, such as TensorFlow, to approach other similarly complex problems. We are already applying the newly discovered methods in further theoretical physics research.

Acknowledgements
This research was conducted by Iulia M. Comşa, Moritz Firsching, and Thomas Fischbacher. Additional thanks go to Jyrki Alakuijala, Rahul Sukthankar, and Jay Yagnik for encouragement and support.

Source: Google AI Blog


SPICE: Self-Supervised Pitch Estimation



A sound’s pitch is a qualitative measure of its frequency, where a sound with a high pitch is higher in frequency than one of low pitch. Through tracking relative differences in pitch, our auditory system is able to recognize audio features, such as a song’s melody. Pitch estimation has received a great deal of attention over the past decades, due to its central importance in several domains, ranging from music information retrieval to speech analysis.

Traditionally, simple signal processing pipelines were proposed to estimate pitch, working either in the time domain (e.g., pYIN) or in the frequency domain (e.g., SWIPE). But until recently, machine learning methods have not been able to outperform such hand-crafted signal processing pipelines. This was due to the lack of annotated data, which is particularly tedious and difficult to obtain at the temporal and frequency resolution required to train fully supervised models. The CREPE model was able to overcome these limitations to achieve state-of-the-art results by training on a synthetically generated dataset combined with other manually annotated datasets.

In our recent paper, we present a different approach to training pitch estimation models in the absence of annotated data. Inspired by the observation that for humans, including professional musicians, it is typically much easier to estimate relative pitch (the frequency interval between two notes) than absolute pitch (the true fundamental frequency), we designed SPICE (Self-supervised PItCh Estimation) to solve a similar task. This approach relies on self-supervision by defining an auxiliary task (also known as a pretext task) that can be learned in a completely unsupervised way.
Constant-Q transform of an audio clip, superimposed on a representation of pitch as estimated by SPICE (video).
The SPICE model consists of a convolutional encoder, which produces a single scalar embedding that maps linearly to pitch. To accomplish this, we feed two signals to the encoder, a reference signal along with a signal that is pitch shifted from the reference by a random, known amount. Then, we devise a loss function that forces the difference between the scalar embeddings to be proportional to the known difference in pitch. For convenience, we perform pitch shifting in the domain defined by the constant-Q transform (CQT), because this corresponds to a simple translation along the log-spaced frequency axis.

Pitch is well defined only when the underlying signal is harmonic, i.e., when it contains components with integer multiples of the fundamental frequency. So, an important function of the model is to determine when the output is meaningful and reliable. For example, in the figure below, there is no harmonic signal in the interval between 1.2s and 2s resulting in low enough confidence in the pitch estimation that no pitch estimate is generated. SPICE is designed to learn the level of confidence of the pitch estimation in a self-supervised fashion, instead of relying on handcrafted solutions.
SPICE model architecture (simplified). Two pitch-shifted versions of the same CQT frame are fed to two encoders with shared weights. The loss is designed to make the difference between the outputs of the encoders proportional to the relative pitch difference. In addition (not shown), a reconstruction loss is added to regularize the model. The model also learns to produce the confidence of the pitch estimation.
We evaluate our model against publicly available datasets and show that we outperform handcrafted baselines while matching the level of accuracy attained by CREPE, despite having no access to ground truth labels. In addition, by properly augmenting our data during training, SPICE is also able to operate in noisy conditions, e.g., to extract pitch from the singing voice when this is mixed in with background music. The chart below shows a comparison between SWIPE (a hand-crafted signal-processing method), CREPE (a fully supervised model) and SPICE (a self-supervised model) on the MIR-1k dataset.
Evaluation on the MIR-1k dataset, mixing in background music at different signal-to-noise ratios.
The SPICE model has been deployed in FreddieMeter, a web app in which singers can score their performance against Freddie Mercury.

Acknowledgments

The work described here was authored by Beat Gfeller, Christian Frank, Dominik Roblek, Matt Sharifi, Marco Tagliasacchi and Mihajlo Velimirović. We are grateful for all discussions and feedback on this work that we received from our colleagues at Google. The SingingVoices dataset used for training the models in this work has been collected by Alexandra Gherghina as part of FreddieMeter, which is using SPICE and a vocal timbre similarity model to understand how closely a singer matches Freddie Mercury.

Source: Google AI Blog


Introducing the Next Generation of On-Device Vision Models: MobileNetV3 and MobileNetEdgeTPU



On-device machine learning (ML) is an essential component in enabling privacy-preserving, always-available and responsive intelligence. This need to bring on-device machine learning to compute and power-limited devices has spurred the development of algorithmically-efficient neural network models and hardware capable of performing billions of math operations per second, while consuming only a few milliwatts of power. The recently launched Google Pixel 4 exemplifies this trend, and ships with the Pixel Neural Core that contains an instantiation of the Edge TPU architecture, Google’s machine learning accelerator for edge computing devices, and powers Pixel 4 experiences such as face unlock, a faster Google Assistant and unique camera features. Similarly, algorithms, such as MobileNets, have been critical for the success of on-device ML by providing compact and efficient neural network models for mobile vision applications.

Today we are pleased to announce the release of source code and checkpoints for MobileNetV3 and the Pixel 4 Edge TPU-optimized counterpart MobileNetEdgeTPU model. These models are the culmination of the latest advances in hardware-aware AutoML techniques as well as several advances in architecture design. On mobile CPUs, MobileNetV3 is twice as fast as MobileNetV2 with equivalent accuracy, and advances the state-of-the-art for mobile computer vision networks. On the Pixel 4 Edge TPU hardware accelerator, the MobileNetEdgeTPU model pushes the boundary further by improving model accuracy while simultaneously reducing the runtime and power consumption.

Building MobileNetV3
In contrast with the hand-designed previous version of MobileNet, MobileNetV3 relies on AutoML to find the best possible architecture in a search space friendly to mobile computer vision tasks. To most effectively exploit the search space we deploy two techniques in sequence — MnasNet and NetAdapt. First, we search for a coarse architecture using MnasNet, which uses reinforcement learning to select the optimal configuration from a discrete set of choices. Then we fine-tune the architecture using NetAdapt, a complementary technique that trims under-utilized activation channels in small decrements. To provide the best possible performance under different conditions we have produced both large and small models.
Comparison of accuracy vs. latency for mobile models on the ImageNet classification task using the Google Pixel 4 CPU.
MobileNetV3 Search Space
The MobileNetV3 search space builds on multiple recent advances in architecture design that we adapt for the mobile environment. First, we introduce a new activation function called hard-swish (h-swish) which is based on the Swish nonlinearity function. The critical drawback of the Swish function is that it is very inefficient to compute on mobile hardware. So, instead we use an approximation that can be efficiently expressed as a product of two piecewise linear functions.
Next we introduce the mobile-friendly squeeze-and-excitation block, which replaces the classical sigmoid function with a piecewise linear approximation.

Combining h-swish plus mobile-friendly squeeze-and-excitation with a modified version of the inverted bottleneck structure introduced in MobileNetV2 yielded a new building block for MobileNetV3.
MobileNetV3 extends the MobileNetV2 inverted bottleneck structure by adding h-swish and mobile friendly squeeze-and-excitation as searchable options.
These parameters defined the search space used in constructing MobileNetV3:
  • Size of expansion layer
  • Degree of squeeze-excite compression
  • Choice of activation function: h-swish or ReLU
  • Number of layers for each resolution block
We also introduced a new efficient last stage at the end of the network that further reduced latency by 15%.
MobileNetV3 Object Detection and Semantic Segmentation
In addition to classification models, we also introduced MobileNetV3 object detection models, which reduced detection latency by 25% relative to MobileNetV2 at the same accuracy for the COCO dataset.

In order to optimize MobileNetV3 for efficient semantic segmentation, we introduced a low latency segmentation decoder called Lite Reduced Atrous Spatial Pyramid Pooling (LR-SPP). This new decoder contains three branches, one for low resolution semantic features, one for higher resolution details, and one for light-weight attention. The combination of LR-SPP and MobileNetV3 reduces the latency by over 35% on the high resolution Cityscapes Dataset.

MobileNet for Edge TPUs
The Edge TPU in Pixel 4 is similar in architecture to the Edge TPU in the Coral line of products, but customized to meet the requirements of key camera features in Pixel 4. The accelerator-aware AutoML approach substantially reduces the manual process involved in designing and optimizing neural networks for hardware accelerators. Crafting the neural architecture search space is an important part of this approach and centers around the inclusion of neural network operations that are known to improve hardware utilization. While operations such as squeeze-and-excite and swish non-linearity have been shown to be essential in building compact and fast CPU models, these operations tend to perform suboptimally on Edge TPU and hence are excluded from the search space. The minimalistic variants of MobileNetV3 also forgo the use of these operations (i.e., squeeze-and-excite, swish, and 5x5 convolutions) to allow easier portability to a variety of other hardware accelerators such as DSPs and GPUs.

The neural network architecture search, incentivized to jointly optimize the model accuracy and Edge TPU latency, produces the MobileNetEdgeTPU model that achieves lower latency for a fixed accuracy (or higher accuracy for a fixed latency) than existing mobile models such as MobileNetV2 and minimalistic MobileNetV3. Compared with the EfficientNet-EdgeTPU model (optimized for the Edge TPU in Coral), these models are designed to run at a much lower latency on Pixel 4, albeit at the cost of some loss in accuracy.

Although reducing the model’s power consumption was not a part of the search objective, the lower latency of the MobileNetEdgeTPU models also helps reduce the average Edge TPU power use. The MobileNetEdgeTPU model consumes less than 50% the power of the minimalistic MobileNetV3 model at comparable accuracy.
Left: Comparison of the accuracy on the ImageNet classification task between MobileNetEdgeTPU and other image classification networks designed for mobile when running on Pixel4 Edge TPU. MobileNetEdgeTPU achieves higher accuracy and lower latency compared with other models. Right: Average Edge TPU power in Watts for different classification models running at 30 frames per second (fps).
Objection Detection Using MobileNetEdgeTPU
The MobileNetEdgeTPU classification model also serves as an effective feature extractor for object detection tasks. Compared with MobileNetV2 based detection models, MobileNetEdgeTPU models offer a significant improvement in model quality (measured as the mean average precision; mAP) on the COCO14 minival dataset at comparable runtimes on the Edge TPU. The MobileNetEdgeTPU detection model has a latency of 6.6ms and achieves mAP score of 24.3, while MobileNetV2-based detection models achieve an mAP of 22 and takes 6.8ms per inference.

The Need for Hardware-Aware Models
While the results shown above highlight the power, performance, and quality benefits of MobileNetEdgeTPU models, it is important to note that the improvements arise due to the fact that these models have been customized to run on the Edge TPU accelerator.
MobileNetEdgeTPU when running on a mobile CPU delivers inferior performance compared with the models that have been tuned specifically for mobile CPUs (MobileNetV3). MobileNetEdgeTPU models perform a much greater number of operations, and so, it is not surprising that they run slower on mobile CPUs, which exhibit a more linear relationship between a model’s compute requirements and the runtime.
MobileNetV3 is still the best performing network when using mobile CPU as the deployment target.
For Researchers and Developers
The MobileNetV3 and MobileNetEdgeTPU code, as well as both floating point and quantized checkpoints for ImageNet classification, are available at the MobileNet github page. Open source implementation for MobileNetV3 and MobileNetEdgeTPU object detection is available in the Tensorflow Object Detection API. Open source implementation for MobileNetV3 semantic segmentation is available in TensorFlow through DeepLab.

Acknowledgements:
This work is made possible through a collaboration spanning several teams across Google. We’d like to acknowledge contributions from Berkin Akin, Okan Arikan, Gabriel Bender, Bo Chen, Liang-Chieh Chen, Grace Chu, Eddy Hsu, John Joseph, Pieter-jan Kindermans, Quoc Le, Owen Lin, Hanxiao Liu, Yun Long, Ravi Narayanaswami, Ruoming Pang, Mark Sandler, Mingxing Tan, Vijay Vasudevan, Weijun Wang, Dong Hyuk Woo, Dmitry Kalenichenko, Yunyang Xiong, Yukun Zhu and support from Hartwig Adam, Blaise Agüera y Arcas, Chidu Krishnan and Steve Molloy.

Source: Google AI Blog


New Insights into Human Mobility with Privacy Preserving Aggregation



Understanding human mobility is crucial for predicting epidemics, urban and transit infrastructure planning, understanding people’s responses to conflict and natural disasters and other important domains. Formerly, the state-of-the-art in mobility data was based on cell carrier logs or location "check-ins", and was therefore available only in limited areas — where the telecom provider is operating. As a result, cross-border movement and long-distance travel were typically not captured, because users tend not to use their SIM card outside the country covered by their subscription plan and datasets are often bound to specific regions. Additionally, such measures involved considerable time lags and were available only within limited time ranges and geographical areas.

In contrast, de-identified aggregate flows of populations around the world can now be computed from phones' location sensors at a uniform spatial resolution. This metric has the potential to be extremely useful for urban planning since it can be measured in a direct and timely way. The use of de-identified and aggregated population flow data collected at a global level via smartphones could shed additional light on city organization, for example, while requiring significantly fewer resources than existing methods.

In “Hierarchical Organization of Urban Mobility and Its Connection with City Livability”, we show that these mobility patterns — statistics on how populations move about in aggregate — indicate a higher use of public transportation, improved walkability, lower pollutant emissions per capita, and better health indicators, including easier accessibility to hospitals. This work, which appears in Nature Communications, contributes to a better characterization of city organization and supports a stronger quantitative perspective in the efforts to improve urban livability and sustainability.
Visualization of privacy-first computation of the mobility map. Individual data points are automatically aggregated together with differential privacy noise added. Then, flows of these aggregate and obfuscated populations are studied.
Computing a Global Mobility Map While Preserving User Privacy
In line with our AI principles, we have designed a method for analyzing population mobility with privacy-preserving techniques at its core. To ensure that no individual user’s journey can be identified, we create representative models of aggregate data by employing a technique called differential privacy, together with k-anonymity, to aggregate population flows over time. Initially implemented in 2014, this approach to differential privacy intentionally adds random “noise” to the data in a way that maintains both users' privacy and the data's accuracy at an aggregate level. We use this method to aggregate data collected from smartphones of users who have deliberately chosen to opt-in to Location History, in order to better understand global patterns of population movements.

The model only considers de-identified location readings aggregated to geographical areas of predetermined sizes (e.g., S2 cells). It "snaps" each reading into a spacetime bucket by discretizing time into longer intervals (e.g., weeks) and latitude/longitude into a unique identifier of the geographical area. Aggregating into these large spacetime buckets goes beyond protecting individual privacy — it can even protect the privacy of communities.

Finally, for each pair of geographical areas, the system computes the relative flow between the areas over a given time interval, applies differential privacy filters, and outputs the global, anonymized, and aggregated mobility map. The dataset is generated only once and only mobility flows involving a sufficiently large number of accounts are processed by the model. This design is limited to heavily aggregated flows of populations, such as that already used as a vital source of information for estimates of live traffic and parking availability, which protects individual data from being manually identified. The resulting map is indexed for efficient lookup and used to fuel the modeling described below.

Mobility Map Applications
Aggregate mobility of people in cities around the globe defines the city and, in turn, its impact on the people who live there. We define a metric, the flow hierarchy (Φ), derived entirely from the mobility map, that quantifies the hierarchical organization of cities. While hierarchies across cities have been extensively studied since Christaller’s work in the 1930s, for individual cities, the focus has been primarily on the differences between core and peripheral structures, as well as whether cities are mono- or poly-centric. Our results instead show that the reality is much more rich than previously thought. The mobility map enables a quantitative demonstration that cities lie across a spectrum of hierarchical organization that strongly correlates with a series of important quality of life indicators, including health and transportation.

Below we see an example of two cities — Paris and Los Angeles. Though they have almost the same population size, those two populations move in very different ways. Paris is mono-centric, with an "onion" structure that has a distinct high-mobility city center (red), which progressively decreases as we move away from the center (in order: orange, yellow, green, blue). On the other hand, Los Angeles is truly poly-centric, with a large number of high-mobility areas scattered throughout the region.
Mobility maps of Paris (left) and Los Angeles (right). Both cities have similar population sizes, but very different mobility patterns. Paris has an "onion" structure exhibiting a distinct center with a high degree of mobility (red) that progressively decreases as we move away from the center (in order: orange, yellow, green, blue). In contrast, Los Angeles has a large number of high-mobility areas scattered throughout the region.
More hierarchical cities — in terms of flows being primarily between hotspots of similar activity levels — have values of flow hierarchy Φ closer to the upper limit of 1 and tend to have greater levels of uniformity in their spatial distribution of movements, wider use of public transportation, higher levels of walkability, lower pollution emissions, and better indicators of various measures of health. Returning to our example, the flow hierarchy of Paris is Φ=0.93 (in the top quartile across all 174 cities sampled), while that of Los Angeles is 0.86 (bottom quartile).

We find that existing measures of urban structure, such as population density and sprawl composite indices, correlate with flow hierarchy, but in addition the flow hierarchy conveys comparatively more information that includes behavioral and socioeconomic factors.
Connecting flow hierarchy Φ with urban indicators in a sample of US cities. Proportion of trips as a function of Φ, broken down by model share: private car, public transportation, and walking. Sample city names that appear in the plot: ATL (Atlanta), CHA (Charlotte), CHI (Chicago), HOU (Houston), LA (Los Angeles), MIN (Minneapolis), NY (New York City), and SF (San Francisco). We see that cities with higher flow hierarchy exhibit significantly higher rates of public transportation use, less car use, and more walkability.
Measures of urban sprawl require composite indices built up from much more detailed information on land use, population, density of jobs, and street geography among others (sometimes up to 20 different variables). In addition to the extensive data requirements, such metrics are also costly to obtain. For example, censuses and surveys require a massive deployment of resources in terms of interviews, and are only standardized at a country level, hindering the correct quantification of sprawl indices at a global scale. On the other hand, the flow hierarchy, being constructed from mobility information alone, is significantly less expensive to compile (involving only computer processing cycles), and is available in real-time.

Given the ongoing debate on the optimal structure of cities, the flow hierarchy, introduces a different conceptual perspective compared to existing measures, and can shed new light on the organization of cities. From a public-policy point of view, we see that cities with greater degree of mobility hierarchy tend to have more desirable urban indicators. Given that this hierarchy is a measure of proximity and direct connectivity between socioeconomic hubs, a possible direction could be to shape opportunity and demand in a way that facilitates a greater degree of hub-to-hub movement than a hub-to-spoke architecture. The proximity of hubs can be generated through appropriate land use, that can be shaped by data-driven zoning laws in terms of business, residence or service areas. The presence of efficient public transportation and lower use of cars is another important factor. Perhaps a combination of policies, such as congestion-pricing, used to disincentivize private transportation to socioeconomic hubs, along with building public transportation in a targeted fashion to directly connect the hubs, may well prove useful.

Next Steps
This work is part of our larger AI for Social Good efforts, a program that focuses Google's expertise on addressing humanitarian and environmental challenges.These mobility maps are only the first step toward making an impact in epidemiology, infrastructure planning, and disaster response, while ensuring high privacy standards.

The work discussed here goes to great lengths to ensure privacy is maintained. We are also working on newer techniques, such as on-device federated learning, to go a step further and enable computing aggregate flows without personal data leaving the device at all. By using distributed secure aggregation protocols or randomized responses, global flows can be computed without even the aggregator having knowledge of individual data points being aggregated. This technique has also been applied to help secure Chrome from malicious attacks.

Acknowledgements
This work resulted from a collaboration of Aleix Bassolas and José J. Ramasco from the Institute for Cross-Disciplinary Physics and Complex Systems (IFISC, CSIC-UIB), Brian Dickinson, Hugo Barbosa-Filho, Gourab Ghoshal, Surendra A. Hazarie, and Henry Kautz from the Computer Science Department and Ghoshal Lab at the University of Rochester, Riccardo Gallotti from the Bruno Kessler Foundation, and Xerxes Dotiwalla, Paul Eastham, Bryant Gipson, Onur Kucuktunc, Allison Lieber, Adam Sadilek at Google.

The differential privacy library used in this work is open source and available on our GitHub repo.

Source: Google AI Blog


Highlights from the 2019 Google AI Residency Program



This fall marks the successful conclusion to the fourth year of the Google AI Residency Program. Started in 2016 with 27 individuals in Mountain View, CA, the 12-month program has grown to nearly 100 residents from nine locations across the globe. Program participants have gone on to great success in PhD programs, academia, non-profits, and industry. Many have also become full-time Google researchers.

The program’s latest installment was our most successful yet, as residents advanced progress in a broad range of research fields, such as machine perception, algorithms and optimization, language understanding, healthcare and many more. Below are a handful of innovative projects from some of this year’s alumni.
  • A large-scale study on cross-lingual transfer in massive multilingual neural machine translation models (recently highlighted as part of this post), trained on billions of sentence pairs from more than 100 languages in order to significantly improve translation for both low- and high-resource languages.
    Visualization of the clustering of encoder representations of all modeled languages, based on representational similarity. Encoder representations of different languages cluster according to linguistic similarity. Languages are color-coded by their linguistic family.
  • A generative model for Scalable Vector Graphics (SVGs), which can be used to aid designers in generating fonts.
  • Top: Unlike pixel representations of icons (right), in this case a "6", SVGs (left; middle) are scale-invariant representations. Bottom: By modelling SVGs directly, we can aid artists in quickly and intuitively iterating over typography designs.
  • A method to learn GANs using discrepancy divergence, a measure that accounts for both the loss function and hypothesis set to provide theoretical learning guarantees.
  • As more generators are added to the DGAN ensemble more modes in the real distribution are covered. From left to right: 1 generator, 5 generators, and 10 generators.
  • A likelihood ratio method for deep generative models that effectively corrects for confounding background statistics to improve out-of-distribution (OOD) detection, and a new benchmark dataset for OOD detection in genomics.
  • Log-likelihood (left) and log likelihood-ratio (right) of each pixel for Fashion-MNIST. The likelihood is dominated by the “background” pixels, whereas the likelihood ratio focuses on the “semantic” pixels and is thus better for OOD detection.
  • A study showing when label smoothing helps, focusing on its impact on calibration of predictions, representations learned by the penultimate layer and effectiveness of knowledge distillation.
  • 2D-projection of representations of three CIFAR100 classes. Without label smoothing, examples are spread, but with label smoothing each example is encouraged to be equally distant to the clusters of the other classes, attenuating intra-class variation and inter-class similarity structure.
The successes of our AI residents go beyond academic publishing. Their achievements include:
  • Organizing a workshop, bringing together experts in theoretical physics and deep learning, to explore how tools from physics can shed light on the theory of deep learning.
  • Founding Queer in AI, an organization for fostering a community of queer researchers and raising awareness of queer issues in AI/ML.
  • Organizing a hands-on Tensorflow tutorial on using Deep Learning for Natural Language Processing.
  • Automatically learning neural net architectures with AdaNet, an open-source, TensorFlow-based framework.
  • Developing Coconet, the model behind the first AI-powered Doodle (created to celebrate renowned German composer and musician Johann Sebastian Bach).
Also, beginning with the next program cycle, residents will be hosted for a duration of 12 months, with the option of extending up to 18 months! This exciting shift comes as part of our effort to improve the overall program experience and outcomes for residents as the program continues to grow and scale.

If you are interested in joining our fifth cohort, applications for the 2020 Google AI Residency program are now open! Visit g.co/airesidency/apply for more information on how to apply. Please submit your application as soon as possible, as we will be considering candidates on a rolling basis. Please see g.co/airesidency for more resident profiles, past resident publications, blog posts and stories. We can’t wait to see where the next year will take us, and hope you’ll consider joining our research teams across the world!

Source: Google AI Blog


The Visual Task Adaptation Benchmark



Deep learning has revolutionized computer vision, with state-of-the-art deep networks learning useful representations directly from raw pixels, leading to unprecedented performance on many vision tasks. However, learning these representations from scratch typically requires hundreds of thousands of training examples. This burden can be reduced by using pre-trained representations, which have become widely available through services such as TensorFlow Hub (TF Hub) and PyTorch Hub. But their ubiquity can itself be a hindrance. For example, for the task of extracting features from images, there can be over 100 models from which to choose. It is hard to know which methods provide the best representations, since different sub-fields use different evaluation protocols, which do not always reflect the final performance on new tasks.

The overarching goal of representation research is to learn representations a single time on large amounts of generic data without the need to train them from scratch for each task, thus reducing data requirements across all vision tasks. But in order to reach that goal, the research community must have a uniform benchmark against which existing and future methods can be evaluated.

To address this problem, we are releasing "The Visual Task Adaptation Benchmark" (VTAB, available on GitHub), a diverse, realistic, and challenging representation benchmark based on one principle — a better representation is one that yields better performance on unseen tasks, with limited in-domain data. Inspired by benchmarks that have driven progress in other fields of machine learning (ML), such as ImageNet for natural image classification, GLUE for Natural Language Processing, and Atari for reinforcement learning, VTAB follows similar guidelines: (i) minimal constraints on solutions to encourage creativity; (ii) a focus on practical considerations; and (iii) challenging tasks for evaluation.

The Benchmark
VTAB is an evaluation protocol designed to measure progress towards general and useful visual representations, and consists of a suite of evaluation vision tasks that a learning algorithm must solve. These algorithms may use pre-trained visual representations to assist them and must satisfy only two requirements:
    i) They must not be pre-trained on any of the data (labels or input images) used in the downstream evaluation tasks.
    ii) They must not contain hardcoded, task-specific, logic. Alternatively put, the evaluation tasks must be treated like a test set — unseen.
These constraints ensure that solutions that are successful when applied to VTAB will be able to generalize to future tasks.

The VTAB protocol begins with the application of an algorithm (A) to a number of independent tasks, drawn from a broad distribution of vision problems. The algorithm may be pre-trained on upstream data to yield a model that contains visual representations, but it must also define an adaptation strategy that consumes a small training set for each downstream task and return a model that makes task-specific predictions. The algorithm’s final score is its average test score across tasks.
The VTAB protocol. Algorithm A is applied to many tasks T, drawn from a broad distribution of vision problems PT. In the example, pet classification, remote sensing, and maze localization are shown.
VTAB includes 19 evaluation tasks that span a variety of domains, divided into three groups — natural, specialized, and structured. Natural image tasks include images of the natural world captured through standard cameras, representing generic objects, fine-grained classes, or abstract concepts. Specialized tasks utilize images captured using specialist equipment, such as medical images or remote sensing. The structured tasks often derive from artificial environments that target understanding of specific changes between images, such as predicting the distance to an object in a 3D scene (e.g., DeepMind Lab), counting objects (e.g., CLEVR), or detecting orientation (e.g., dSprites for disentangled representations).

While highly diverse, all of the tasks in VTAB share one common feature — people can solve them relatively easily after training on just a few examples. To assess algorithmic generalization to new tasks with limited data, performance is evaluated using only 1000 examples per task. Evaluation using the full dataset can be performed for comparison with previous publications.

Findings Using VTAB
We performed a large scale study testing a number of popular visual representation learning algorithms against VTAB. The study included generative models (GANs and VAEs), self-supervised models, semi-supervised models and supervised models. All of the algorithms were pre-trained on the ImageNet dataset. We also compared each of these approaches using no pre-trained representations, i.e., training “from-scratch”. The figure below summarizes the main pattern of results.
Performance of different classes of representation learning algorithms across different task groups: natural, specialized and structured. Each bar shows the average performance of all methods in that class across all tasks in the group.
Overall we find that generative models do not perform as well as the other methods, even worse than from-scratch training. However, self-supervised models perform much better, significantly outperforming from-scratch training. Better still is supervised learning using the ImageNet labels. Interestingly, while supervised learning is significantly better on the Natural group of tasks, self-supervised learning is close on the other two groups whose domains are more dissimilar to ImageNet.

The best performing representation learning algorithm, of those we tested, is S4L, which combines both supervised and self-supervised pre-training losses. The figure below contrasts S4L with standard supervised ImageNet pre-training. S4L appears to improve performance particularly on the Structured tasks. However, representation learning yields a much smaller benefit over training from-scratch groups other than the Natural tasks, indicating that there is much progress required to attain a universal visual representation.
Top: Performance of S4L versus from-scratch training. Each bar corresponds to a task. Positive-valued bars indicate tasks where S4L outperforms from-scratch. Negative bars indicate that from-scratch performed better. Bottom: S4L versus Supervised training on ImageNet. Positive bars indicate that S4L performs better. The bar colour indicates the task group: Red=Natural, Green=Specialized, Blue=Structured. We can see that additional self-supervision tends to help on structured tasks beyond just using ImageNet labels.
Summary
The code to run VTAB is available on GitHub, including the 19 evaluation datasets and exact data splits. Having a publicly available set of benchmarks ensures the reproducibility of results. Progress is tracked with the public leaderboard, and the models evaluated are uploaded to TF Hub for public use and reproduction. A shell script is provided to perform adaptation and evaluation on all the tasks, with a standardized evaluation protocol making VTAB readily accessible across the industry. Since VTAB can be executed on both TPU and GPU, it is highly efficient. One can obtain comparable results with a single NVIDIA Tesla P100 accelerator in a few hours.

The Visual Task Adaptation Benchmark has helped us better understand which visual representations generalize to the broad spectrum of vision tasks, and provides direction for future research. We hope these resources are useful in driving progress toward general and practical visual representations, and as a result, affords deep learning to the long tail of vision problems with limited labelled data.

Acknowledgements
The core team behind this work includes Joan Puigcerver, Alexander Kolesnikov, Pierre Ruyssen, Carlos Riquelme, Mario Lucic, Josip Djolonga, Andre Susano Pinto, Maxim Neumann, Alexey Dosovitskiy, Lucas Beyer, Olivier Bachem, Michael Tschannen, Marcin Michalski, Olivier Bousquet, and Sylvain Gelly.

Source: Google AI Blog


Learning to Assemble and to Generalize from Self-Supervised Disassembly



Our physical world is full of different shapes, and learning how they are all interconnected is a natural part of interacting with our surroundings — for example, we understand that coat hangers hook onto clothing racks, power plugs insert into wall outlets, and USB cables fit into USB sockets. This general concept of “how things fit together'' based on their shapes is something that people acquire over time and experience, and it helps to increase the efficiency with which we perform tasks, like assembling DIY furniture kits or packing gifts into a box. If robots could learn “how things fit together,” then perhaps they could become more adaptable to new manipulation tasks involving objects they have never seen before, like reconnecting severed pipes, or building makeshift shelters by piecing together debris during disaster response scenarios.

To explore this idea, we worked with researchers from Stanford and Columbia Universities to develop Form2Fit, a robotic manipulation algorithm that uses deep neural networks to learn to visually recognize how objects correspond (or “fit”) to each other. To test this algorithm, we tasked a real robot to perform kit assembly, where it needed to accurately assemble objects into a blister pack or corrugated display to form a single unit. Previous systems built for this task required extensive manual tuning to assemble a single kit unit at a time. However, we demonstrate that by learning the general concept of “how things fit together,” Form2Fit enables our robot to assemble various types of kits with a 94% success rate. Furthermore, Form2Fit is one of the first systems capable of generalizing to new objects and kitting tasks not seen during training.
Form2Fit learns to assemble a wide variety of kits by finding geometric correspondences between object surfaces and their target placement locations. By leveraging geometric information learned from multiple kits during training, the system generalizes to new objects and kits.
While often overlooked, shape analysis plays an important role in manipulation, especially for tasks like kit assembly. In fact, the shape of an object often matches the shape of its corresponding space in the packaging, and understanding this relationship is what allows people to do this task with minimal guesswork. At its core, Form2Fit aims to learn this relationship by training over numerous pairs of objects and their corresponding placing locations across multiple different kitting tasks – with the goal to acquire a broader understanding of how shapes and surfaces fit together. Form2Fit improves itself over time with minimal human supervision, gathering its own training data by repeatedly disassembling completed kits through trial and error, then time-reversing the disassembly sequences to get assembly trajectories. After training overnight for 12 hours, our robot learns effective pick and place policies for a variety of kits, achieving 94% assembly success rates with objects and kits in varying configurations, and over 86% assembly success rates when handling completely new objects and kits.

Data-Driven Shape Descriptors For Generalizable Assembly
The core component of Form2Fit is a two-stream matching network that learns to infer orientation-sensitive geometric pixel-wise descriptors for objects and their target placement locations from visual data. These descriptors can be understood as compressed 3D point representations that encode object geometry, textures, and contextual task-level knowledge. Form2Fit uses these descriptors to establish correspondences between objects and their target locations (i.e., where they should be placed). Since these descriptors are orientation-sensitive, they allow Form2Fit to infer how the picked object should be rotated before it is placed in its target location.

Form2Fit uses two additional networks to generate valid pick and place candidates. A suction network gets fed a 3D image of the objects and generates pixel-wise predictions of suction success. The suction probability map is visualized as a heatmap, where hotter pixels indicate better locations to grasp the object at the 3D location of the corresponding pixel. In parallel, a place network gets fed a 3D image of the target kit and outputs pixel-wise predictions of placement success. These, too, are visualized as a heatmap, where higher confidence values serve as better locations for the robot arm to approach from a top-down angle to place the object. Finally, the planner integrates the output of all three modules to produce the final pick location, place location and rotation angle.
Overview of Form2Fit. The suction and place networks infer candidate picking and placing locations in the scene respectively. The matching network generates pixel-wise orientation-sensitive descriptors to match picking locations to their corresponding placing locations. The planner then integrates it all to control the robot to execute the next best pick and place action.
Learning Assembly from Disassembly
Neural networks require large amounts of training data, which can be difficult to collect for tasks like assembly. Precisely inserting objects into tight spaces with the correct orientation (e.g., in kits) is challenging to learn through trial and error, because the chances of success from random exploration can be slim. In contrast, disassembling completed units is often easier to learn through trial and error, since there are fewer incorrect ways to remove an object than there are to correctly insert it. We leveraged this difference in order to amass training data for Form2Fit.
An example of self-supervision through time-reversal: rewinding a disassembly sequence of a deodorant kit over time generates a valid assembly sequence.
Our key observation is that in many cases of kit assembly, a disassembly sequence – when reversed over time – becomes a valid assembly sequence. This concept, called time-reversed disassembly, enables Form2Fit to train entirely through self-supervision by randomly picking with trial and error to disassemble a fully-assembled kit, then reversing that disassembly sequence to learn how the kit should be put together.

Generalization Results
The results of our experiments show great potential for learning generalizable policies for assembly. For instance, when a policy is trained to assemble a kit in only one specific position and orientation, it can still robustly assemble random rotations and translations of the kit 90% of the time.
Form2Fit policies are robust to a wide range of rotations and translations of the kits.
We also find that Form2Fit is capable of tackling novel configurations it has not been exposed to during training. For example, when training a policy on two single-object kits (floss and tape), we find that it can successfully assemble new combinations and mixtures of those kits, even though it has never seen such configurations before.
Form2Fit policies can generalize to novel kit configurations such as multiple versions of the same kit and mixtures of different kits.
Furthermore, when given completely novel kits on which it has not been trained, Form2Fit can generalize using its learned shape priors to assemble those kits with over 86% assembly accuracy.
Form2Fit policies can generalize to never-before-seen single and multi-object kits.
What Have the Descriptors Learned?
To explore what the descriptors of the matching network from Form2Fit have learned to encode, we visualize the pixel-wise descriptors of various objects in RGB colorspace through use of an embedding technique called t-SNE.
The t-SNE embedding of the learned object descriptors. Similarly oriented objects of the same category display identical colors (e.g. A, B or F, G) while different objects (e.g. C, H) and same objects but different orientation (e.g. A, C, D or H, F) exhibit different colors.
We observe that the descriptors have learned to encode (a) rotation — objects oriented differently have different descriptors (A, C, D, E) and (H, F); (b) spatial correspondence — same points on the same oriented objects share similar descriptors (A, B) and (F, G); and (c) object identity — zoo animals and fruits exhibit unique descriptors (columns 3 and 4).

Limitations & Future Work
While Form2Fit’s results are promising, its limitations suggest directions for future work. In our experiments, we assume a 2D planar workspace to constrain the kit assembly task so that it can be solved by sequencing top-down picking and placing actions. This may not work for all cases of assembly – for example, when a peg needs to be precisely inserted at a 45 degree angle. It would be interesting to expand Form2Fit to more complex action representations for 3D assembly.

You can learn more about this work and download the code from our GitHub repository.


Acknowledgments
This research was done by Kevin Zakka, Andy Zeng, Johnny Lee, and Shuran Song (faculty at Columbia University), with special thanks to Nick Hynes, Alex Nichol, and Ivan Krasin for fruitful technical discussions; Adrian Wong, Brandon Hurd, Julian Salazar, and Sean Snyder for hardware support; Ryan Hickman for valuable managerial support; and Chad Richards for helpful feedback on writing.

Source: Google AI Blog


On-Device Captioning with Live Caption



Captions for audio content are essential for the deaf and hard of hearing, but they benefit everyone. Watching video without audio is common — whether on the train, in meetings, in bed or when the kids are asleep — and studies have shown that subtitles can increase the duration of time that users spend watching a video by almost 40%. Yet caption support is fragmented across apps and even within them, resulting in a significant amount of audio content that remains inaccessible, including live blogs, podcasts, personal videos, audio messages, social media and others.
Recently we introduced Live Caption, a new Android feature that automatically captions media playing on your phone. The captioning happens in real time, completely on-device, without using network resources, thus preserving privacy and lowering latency. The feature is currently available on Pixel 4 and Pixel 4 XL, will roll out to Pixel 3 models later this year, and will be more widely available on other Android devices soon.
When media is playing, Live Caption can be launched with a single tap from the volume control to display a caption box on the screen.
Building Live Caption for Accuracy and Efficiency
Live Caption works through a combination of three on-device deep learning models: a recurrent neural network (RNN) sequence transduction model for speech recognition (RNN-T), a text-based recurrent neural network model for unspoken punctuation, and a convolutional neural network (CNN) model for sound events classification. Live Caption integrates the signal from the three models to create a single caption track, where sound event tags, like [APPLAUSE] and [MUSIC], appear without interrupting the flow of speech recognition results. Punctuation symbols are predicted while text is updated in parallel.

Incoming sound is processed through a Sound Recognition and ASR feedback loop. The produced text or sound label is formatted and added to the caption.
For sound recognition, we leverage previous work that was done for sound events detection, using a model that was built on top of the AudioSet dataset. The Sound Recognition model is used not only to generate popular sound effect labels but also to detect speech periods. The full automatic speech recognition (ASR) RNN-T engine runs only during speech periods in order to minimize memory and battery usage. For example, when music is detected and speech is not present in the audio stream, the [MUSIC] label will appear on screen, and the ASR model will be unloaded. The ASR model is only loaded back into memory when speech is present in the audio stream again.

In order for Live Caption to be most useful, it should be able to run continuously for long periods of time. To do this, Live Caption’s ASR model is optimized for edge-devices using several techniques, such as neural connection pruning, which reduced the power consumption to 50% compared to the full sized speech model. Yet while the model is significantly more energy efficient, it still performs well for a variety of use cases, including captioning videos, recognizing short queries and narrowband telephony speech, while also being robust to background noise.

The text-based punctuation model was optimized for running continuously on-device using a smaller architecture than the cloud equivalent, and then quantized and serialized using the TensorFlow Lite runtime. As the caption is formed, speech recognition results are rapidly updated a few times per second. In order to save on computational resources and provide a smooth user experience, the punctuation prediction is performed on the tail of the text from the most recently recognized sentence, and if the next updated ASR results do not change that text, the previously punctuated results are retained and reused.

Looking forward
Live Caption is now available in English on Pixel 4 and will soon be available on Pixel 3 and other Android devices. We look forward to bringing this feature to more users by expanding its support to other languages and by further improving the formatting in order to improve the perceived accuracy and coherency of the captions, particularly for multi-speaker content.

Acknowledgements
The core team includes Robert Berry, Anthony Tripaldi, Danielle Cohen, Anna Belozovsky, Yoni Tsafir, Elliott Burford, Justin Lee, Kelsie Van Deman, Nicole Bleuel, Brian Kemler, and Benny Schlesinger. We would like to thank the Google Speech team, especially Qiao Liang, Arun Narayanan, and Rohit Prabhavalkar for their insightful work on the ASR model as well as Chung-Cheng Chiu from Google Brain Team; Dan Ellis and Justin Paul for their help with integrating the Sound Recognition model; Tal Remez for his help in developing the punctuation model; Kevin Rocard and Eric Laurent‎ for their help with the Android audio capture API; and Eugenio Marchiori, Shivanker Goel, Ye Wen, Jay Yoo, Asela Gunawardana, and Tom Hume for their help with the Android infrastructure work.

Source: Google AI Blog


Introducing the Schema-Guided Dialogue Dataset for Conversational Assistants



Today's virtual assistants help users to accomplish a wide variety of tasks, including finding flights, searching for nearby events and movies, making reservations, sourcing information from the web and more. They provide this functionality by offering a unified natural language interface to a wide variety of services across the web. Large-scale virtual assistants, like Google Assistant, need to integrate with a large and constantly increasing number of services, each with potentially overlapping functionality, over a wide variety of domains. Supporting new services with ease, without collection of additional data or retraining the model, and reducing maintenance workload are necessary to accommodate future growth. Despite tremendous progress, however, these challenges have often been overlooked in state-of-the-art models. This is due, in part, to the absence of suitable datasets that match the scale and complexity confronted by such virtual assistants.

In our recent paper, “Towards Scalable Multi-domain Conversational Agents: The Schema-Guided Dialogue Dataset”, we introduce a new dataset to address these problems. The Schema-Guided Dialogue dataset (SGD) is the largest publicly available corpus of task-oriented dialogues, with over 18,000 dialogues spanning 17 domains. Equipped with various annotations, this dataset is designed to serve as an effective testbed for intent prediction, slot filling, state tracking (i.e., estimating the user's goal) and language generation, among other tasks for large-scale virtual assistants. We also propose a schema-guided approach for building virtual assistants as a solution to the aforementioned challenges. Our approach utilizes a single model across all services and domains, with no domain-specific parameters. Based on the schema-guided approach and building on the power of pre-trained language models like BERT, we open source a model for dialogue state tracking, which is applicable in a zero-shot setting (i.e., with no training data for new services and APIs) while remaining competitive in the regular setting.

The Dataset
The primary goal of releasing the SGD dataset is to confront many real-world challenges that are not sufficiently captured by existing datasets. The SGD dataset consists of over 18k annotated multi-domain, task-oriented conversations between a human and a virtual assistant. These conversations involve interactions with services and APIs spanning 17 domains, ranging from banks and events to media, calendar, travel, and weather. For most of these domains, the SGD dataset contains multiple different APIs, many of which have overlapping functionalities but different interfaces, which reflects common real-world scenarios. SGD is the first dataset to cover such a wide variety of domains and provide multiple APIs per domain. Furthermore, to quantify the robustness of models to changes in API interfaces or to the addition of new APIs, the evaluation set contains many new services that are not present in the training set.

For the creation of the SGD dataset, we have prioritized the variety and accuracy of annotations in the included dialogues. To begin with, dialogues were collected by interaction between two people using a Wizard-of-Oz style process, followed by crowdsourced annotation. Initial efforts revealed the difficulty in obtaining consistent annotations using this method, so we developed a new data collection process that minimized the need for complex manual annotation, and considerably reduced the time and cost of data collection.

For this alternate approach, we developed a multi-domain dialogue simulator that generates dialogue skeletons over an arbitrary combination of APIs, along with the corresponding annotations, such as dialogue state and system actions. The simulator consists of two agents playing the role of the user and the assistant. Both the agents interact with each other using a finite set of actions denoting dialogue semantics with transitions specified through a probabilistic automaton, designed to capture a wide variety of dialogue trajectories. The actions generated by the simulator are converted into natural language utterances using a set of templates. Crowdsourcing is used only for paraphrasing these templatized utterances in order to make the dialogue more natural and coherent. This setup eliminates the need for complicated domain-specific instructions while keeping the crowdsourcing task simple and yields natural dialogues with consistent, high quality annotations.
Steps for obtaining dialogues, with assistant turns marked in red and user turns in blue. Left: The simulator generates a dialogue skeleton using a finite set of actions. Center: Actions are converted into utterances using templates (~50 per service) and slot values are replaced with natural variations. Right: Paraphrasing via crowdsourcing to make the flow cohesive.
The Schema-Guided Approach
With the availability of the SGD dataset, it is now possible to train virtual assistants to support the diversity of services available on the web. A common approach to do this requires a large master schema that lists all supported functions and their parameters. However, it is difficult to develop a master schema catering to all possible use cases. Even if that problem is solved, a master schema would complicate integration of new or small-scale services and would increase the maintenance workload of the assistant. Furthermore, while there are many similar concepts across services that can be jointly modeled, for example, the similarities in logic for querying or specifying the number of movie tickets, flight tickets or concert tickets, the master schema approach does not facilitate joint modeling of such concepts, unless an explicit mapping between them is manually defined.

The new schema-guided approach we propose addresses these limitations. This approach does not require the definition of a master schema for the assistant. Instead, each service or API provides a natural language description of the functions listed in its schema along with their associated attributes. These descriptions are then used to learn a distributed semantic representation of the schema, which is given as an additional input to the dialogue system. The dialogue system is then implemented as a single unified model, containing no domain or service specific parameters. This unified model facilitates representation of common knowledge between similar concepts in different services, while the use of distributed representations of the schema makes it possible to operate over new services that are not present in the training data. We have implemented this approach in our open-sourced dialogue state tracking model.

Eighth Dialogue System Technology Challenge
The Dialog System Technology Challenges (DSTCs) are a series of research competitions to accelerate the development of new dialogue technologies. This year, Google organized one of the tracks, "Schema-Guided Dialogue State Tracking", as part of the recently concluded 8th DSTC. We received submissions from a total of 25 teams from both industry and academia, which will be presented at the DSTC8 workshop at AAAI-20.

We believe that this dataset will act as a good benchmark for building large-scale dialogue models. We are excited and looking forward to all the innovative ways in which the research community will use it for the advancement of dialogue technologies.

Acknowledgements
This post reflects the work of our co-authors Xiaoxue Zang, Srinivas Sunkara and Raghav Gupta. We also thank Amir Fayazi and Maria Wang for help with data collection and Guan-Lin Chao for insights on model design and implementation.

Source: Google AI Blog


Google at ICCV 2019



This week, Seoul, South Korea hosts the International Conference on Computer Vision 2019 (ICCV 2019), one of the world's premier conferences on computer vision. As a leader in computer vision research and a Gold Sponsor, Google will have a strong presence at ICCV 2019 with over 200 Googlers in attendance, more than 40 research presentations, and involvement in the organization of a number of workshops and tutorials.

If you are attending ICCV this year, please stop by our booth. There you can chat with researchers who are actively pursuing the latest innovations in computer vision and demo some of their latest research, including the technology behind MediaPipe, the new Open Images dataset, new developments for Google Lens and much more.

This year Google researchers are recipients of three prestigious ICCV awards:
More details about the Google research being presented at ICCV 2019 can be found below (Google affiliations in blue).

Organizing Committee includes:
Ming-Hsuan Yang (Program Chair)

Oral Presentations
Learning Single Camera Depth Estimation using Dual-Pixels
Rahul Garg, Neal Wadhwa, Sameer Ansari, Jonathan Barron 

RIO: 3D Object Instance Re-Localization in Changing Indoor Environments
Johanna Wald, Armen Avetisyan, Nassir Navab, Federico Tombari, Matthias Niessner 

ShapeMask: Learning to Segment Novel Objects by Refining Shape Priors
Weicheng Kuo, Anelia Angelova, Jitendra Malik, Tsung-Yi Lin 

PuppetGAN: Cross-Domain Image Manipulation by Demonstration
Ben Usman, Nick Dufour, Kate Saenko, Chris Bregler

COCO-GAN: Generation by Parts via Conditional Coordinating
Chieh Hubert Lin, Chia-Che Chang, Yu-Sheng Chen, Da-Cheng Juan, Wei Wei, Hwann-Tzong Chen

Towards Unconstrained End-to-End Text Spotting
Siyang Qin, Alessandro Bissaco, Michalis Raptis, Yasuhisa Fujii, Ying Xiao

SinGAN: Learning a Generative Model from a Single Natural Image
Tamar Rott Shaham, Tali Dekel, Tomer Michaeli 
(ICCV 2019 Marr Prize Winner — Best Paper Award)

Generative Modeling for Small-Data Object Detection
Lanlan Liu, Michael Muelly, Jia Deng, Tomas Pfister, Li-Jia Li 

Searching for MobileNetV3
Andrew Howard, Mark Sandler, Bo Chen, Weijun Wang, Liang-Chieh Chen, Mingxing Tan, Grace Chu, Vijay Vasudevan, Yukun Zhu, Ruoming Pang, Hartwig Adam, Quoc Le 

S⁴L: Self-Supervised Semi-supervised Learning
Lucas Beyer, Xiaohua Zhai, Avital Oliver, Alexander Kolesnikov 

Sampling-Free Epistemic Uncertainty Estimation Using Approximated Variance Propagation
Janis Postels, Francesco Ferroni, Huseyin Coskun, Nassir Navab, Federico Tombari

Linearized Multi-sampling for Differentiable Image Transformation
Wei Jiang, Weiwei Sun, Andrea Tagliasacchi, Eduard Trulls, Kwang Moo Yi 

Poster Presentations
ELF: Embedded Localisation of Features in Pre-trained CNN
Assia Benbihi, Matthieu Geist, Cedric Pradalier 

Depth from Videos in the Wild: Unsupervised Monocular Depth Learning from Unknown Cameras
Ariel Gordon, Hanhan Li, Rico Jonschkowski, Anelia Angelova

ForkNet: Multi-branch Volumetric Semantic Completion from a Single Depth Image
Yida Wang, David Joseph Tan, Nassir Navab, Federico Tombari 

A Learned Representation for Scalable Vector Graphics
Raphael Gontijo Lopes, David Ha, Douglas Eck, Jonathon Shlens 

FrameNet: Learning Local Canonical Frames of 3D Surfaces from a Single RGB Image
Jingwei Huang, Yichao Zhou, Thomas Funkhouser, Leonidas Guibas

Prior-Aware Neural Network for Partially-Supervised Multi-Organ Segmentation
Yuyin Zhou, Zhe Li, Song Bai, Xinlei Chen, Mei Han, Chong Wang, Elliot Fishman, Alan Yuille 

Boundless: Generative Adversarial Networks for Image Extension
Dilip Krishnan, Piotr Teterwak, Aaron Sarna, Aaron Maschinot, Ce Liu, David Belanger, William Freeman

Cap2Det: Learning to Amplify Weak Caption Supervision for Object Detection
Keren Ye, Mingda Zhang, Adriana Kovashka, Wei Li, Danfeng Qin, Jesse Berent 

NOTE-RCNN: NOise Tolerant Ensemble RCNN for Semi-supervised Object Detection
Jiyang Gao, Jiang Wang, Shengyang Dai, Li-Jia Li, Ram Nevatia 

Object-Driven Multi-Layer Scene Decomposition from a Single Image
Helisa Dhamo, Nassir Navab, Federico Tombari 

Improving Adversarial Robustness via Guided Complement Entropy
Hao-Yun Chen, Jhao-Hong Liang, Shih-Chieh Chang, Jia-Yu Pan, Yu-Ting Chen, Wei Wei, Da-Cheng Juan 

XRAI: Better Attributions Through Regions
Andrei Kapishnikov, Tolga Bolukbasi, Fernanda Viegas, Michael Terry

SegSort: Segment Sorting for Semantic Segmentation
Jyh-Jing Hwang, Stella Yu, Jianbo Shi, Maxwell Collins, Tien-Ju Yang, Xiao Zhang, Liang-Chieh Chen 

Self-Supervised Learning with Geometric Constraints in Monocular Video: Connecting Flow, Depth, and Camera
Yuhua Chen, Cordelia Schmid, Cristian Sminchisescu 

VideoBERT: A Joint Model for Video and Language Representation Learning
Chen Sun, Austin Myers, Carl Vondrick, Kevin Murphy, Cordelia Schmid 

Explaining the Ambiguity of Object Detection and 6D Pose from Visual Data
Fabian Manhardt, Diego Martín Arroyo, Christian Rupprecht, Benjamin  Busam, Tolga Birdal, Nassir Navab, Federico Tombari 

Constructing Self-Motivated Pyramid Curriculums for Cross-Domain Semantic Segmentation
Qing Lian, Lixin Duan, Fengmao Lv, Boqing Gong 

Learning Shape Templates Using Structured Implicit Functions
Kyle Genova, Forrester Cole, Daniel Vlasic, Aaron Sarna, William Freeman, Thomas Funkhouser

Transferable Representation Learning in Vision-and-Language Navigation
Haoshuo Huang, Vihan Jain, Harsh Mehta, Alexander Ku, Gabriel Magalhaes, Jason Baldridge, Eugene Ie 

Controllable Attention for Structured Layered Video Decomposition
Jean-Baptiste Alayrac, Joao Carreira, Relja Arandjelović, Andrew Zisserman

Pixel2Mesh++: Multi-view 3D Mesh Generation via Deformation
Chao Wen, Yinda Zhang, Zhuwen Li, Yanwei Fu

Beyond Cartesian Representations for Local Descriptors
Patrick Ebel, Anastasiia Mishchuk, Kwang Moo Yi, Pascal Fua, Eduard Trulls

Domain Randomization and Pyramid Consistency: Simulation-to-Real Generalization without Accessing Target Domain Data
Xiangyu Yue, Yang Zhang, Sicheng Zhao, Alberto Sangiovanni-Vincentelli, Kurt Keutzer, Boqing Gong 

Evolving Space-Time Neural Architectures for Videos
AJ Piergiovanni, Anelia Angelova, Alexander Toshev, Michael Ryoo 

Moulding Humans: Non-parametric 3D Human Shape Estimation from Single Images
Valentin Gabeur, Jean-Sebastien Franco, Xavier Martin, Cordelia Schmid, Gregory Rogez

Multi-view Image Fusion
Marc Comino Trinidad, Ricardo Martin-Brualla, Florian Kainz, Janne Kontkanen 

EvalNorm: Estimating Batch Normalization Statistics for Evaluation
Saurabh Singh, Abhinav Shrivastava

Attention Augmented Convolutional Networks
Irwan Bello, Barret Zoph, Quoc Le, Ashish Vaswani, Jonathon Shlens 

Patchwork: A Patch-wise Attention Network for Efficient Object Detection and Segmentation in Video Streams
Yuning Chai

Workshops
Low-Power Computer Vision
Organizers include: Bo Chen

Neural Architects
Organizers include: Barret Zoph

The 3rd YouTube-8M Large-Scale Video Understanding Workshop
Organizers include: Paul NatsevCordelia SchmidRahul SukthankarJoonseok LeeGeorge Toderici

Should We Pre-register Experiments in Computer Vision?
Organizers include: Jack Valmadre

Extreme Vision Modeling
Organizers include: Rahul Sukthankar

Joint COCO and Mapillary Recognition Challenge
Organizers include: Tsung-Yi Lin, Yin Cui

Open Images Challenge
Organizers include: Vittorio Ferrari, Alina Kuznetsova, Rodrigo Benenson, Victor Gomes, Matteo Malloci

Tutorials
Meta-Learning and Metric Learning Algorithms
Organizers include: Kevin Swersky

Source: Google AI Blog