Conference Paper

MURE: fast agent based crowd simulation for VFX and Animation

Authors:
To read the full-text of this research, you can request a copy directly from the authors.

Abstract

Crowd simulation in visual effects and animation is a field where creativity is often bound by the scalability of its tools. High end animation systems like Autodesk Maya [Autodesk ] are tailored for scenes with at most tens of characters, whereas more scaleable VFX packages like SideFX's Houdini [SideFX] can lack the directability required by character animation. We present a suite of technologies built around Houdini that vastly improves both its scalability and directability for agent based crowd simulation. Dubbed MURE (Japanese for "crowd"), this system employs a new VEX context with lock-free, multithreaded KD-Tree construction/look-up, a procedural finite state machine for massive animation libraries, a suite of VEX nodes for fuzzy logic, and a fast GPU drawing plugin built upon the open source USD (Universal Scene Description) library [Pixar Animation Studios ]. MURE has proven its success on two feature films, The Good Dinosaur, and Finding Dory, with crowd spectacles including flocks of birds, swarms of fireflies, automobile traffic, and schools of fish. Pixar has a history with agent based crowd simulation using a custom Massive [Massive Software] based pipeline, first developed on Ratatouille [Ryu and Kanyuk 2007], and subsequently used on Wall-E, Up, and Cars 2. A re-write of the studio's proprietary animation software, Presto, deprecated this crowd pipeline. The crowds team on Brave and Monster's University replaced it with a new system for "non-simulated" crowds that sequenced geometry caches [Kanyuk et al. 2012] via finite state machines and sketch based tools [Arumugam et al. 2013]. However, the story reels for The Good Dinosaur called for large crowds with such complex inter-agent and environment interaction that simulated crowds were necessary. This creative need afforded Pixar's crowd team the opportunity of evaluate the pros and cons of our former agent based simulation pipeline and weigh which features would be part of its successor. Fuzzy logic brains and customizable navigation were indispensable, but our practice of approximating hero quality rigs with simulatable equivalents was fraught with problems. Creating the mappings was labor intensive, lossy, and even when mostly correct, animators found the synthesized animation splines so foreign that many would start from scratch rather than build upon a crowd simulation. The avoid this pitfall, we instead opted to start building our new pipeline around pre-cached clips of animation and thus always be able to deliver crowd animators clean splines. This reliance on caches also affords tremendous opportunities for interactivity at massive scales. Thus, rather than focusing on rigging/posing, the goals of our new system, MURE, became interactivity and directability.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the authors.

... • Virtual conditions Crowd investigation strategies can be utilized to comprehend the basic marvel accordingly empowering us to set up numerical models that can give precise reproductions. These numerical models can be additionally utilized for recreation of group wonders for different applications, for example PC games, embedding special visualizations in film scenes and planning clearing plans (Gustafson et al. 2016;Perez et al. 2016). • Forensic investigation Crowd investigation also be utilized to look for suspect and casualties in occasions like besieging, shooting or mishaps in huge social events. ...
Article
Full-text available
Crowd counting is one of the most challenging issues in the computer vision community for safety and security through surveillance systems. It has extensive range of applications, such as disaster management, surveillance event detection, intelligence gathering and analysis, public safety control, traffic monitoring, design of public spaces, anomaly detection and military. Early approaches still encounter many issues like non-uniform density distribution, partial occlusion and discrepancies in scale and perspective. To address the above problems, feature pyramid networks are introduced in deep convolution networks for counting the individuals in the crowd. The designed network has extracted the features at all resolutions and is constructed rapidly from only one input image. This method achieves outperformance results compared to the well-known networks on three standard crowd counting datasets.
... 1145/3214745.3214803 in SideFX's Houdini [SideFX, [n. d.]] via our MURE tools [Gustafson et al., 2016], the crowds team on Incredibles 2 produced rich scenes of busy streets and urban panic. ...
Conference Paper
The stylized world of Incredibles 2 features large urban crowds both in everyday situations and in scenes of panicked mayhem. While Pixar's now academy award winning animation software, Presto, has allowed us to create expressive and nuanced rigs for our crowd characters, our proprietary approach has made it difficult to utilize animation from external sources, such as crowd simulations or from motion capture. In this talk, we discuss how we can automatically approximate our complex rigs with skinned skeletons, as well as how this has opened up our crowd pipeline to procedural look-ats, motion blending, ragdoll physics, and motion capture. In particular, the use of motion capture is novel for Pixar, and finding a way to integrate this workflow into our animator-centric pipeline and culture has been an ongoing effort. The system we designed allows us to capture motion data for multiple characters in the context of complex shots in Presto, and it facilitates choreography of nuanced and specifically timed crowd motions. Together with traditional hand animated motion cycles, our crowd choreography tools in Presto [Arumugam et al., 2013], and skeletal agent based simulation in SideFX's Houdini [SideFX, [n. d.]] via our MURE tools [Gustafson et al., 2016], the crowds team on Incredibles 2 produced rich scenes of busy streets and urban panic.
... This allows fast iteration and is easily interchangeable with a full animation rig when additional specificity is needed. MURE [Gustafson et al. 2016] Permission to make digital or hard copies of part or all of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for third-party components of this work must be honored. ...
Conference Paper
Coco, Pixar's largest human-based crowds film to date, was ambitious both visually and technically. Over a third of the film contains crowd scenes, ranging from a mansion-filled dance party to thousands of skeleton families journeying across a bridge, to a colossal cheering stadium. This complexity required vast amounts of both animation specificity and look variation in our characters. Asset management, animation directability, and rendering would have been extremely difficult with our previous pipeline for human crowds at this scale. An array of techniques were developed to tackle these challenges, including crowd asset and workflow improvements; a new skeletal rigging and posing system to procedurally control animation; more automated, aggressive shading and geometric level of detail; and optimized geometry unrolling in Katana to significantly reduce scene processing time and file IO.
... Virtual environments: Crowd analysis methods can be used to understand the underlying phenomenon thereby enabling us to establish mathematical models that can provide accurate simulations. These mathematical models can be further used for simulation of crowd phenomena for various applications such as computer games, inserting visual e↵ects in film scenes and designing evacuation plans[36,74]. Forensic search: Crowd analysis can be used to search for suspects and victims in events such as bombing, shooting or accidents in large gatherings. Traditional face detection and recognition algorithms can be speeded up using crowd analysis techniques which are more adept at handling such scenarios[47,7]. ...
Article
Full-text available
Estimating count and density maps from crowd images has a wide range of applications such as video surveillance, traffic monitoring, public safety and urban planning. In addition, techniques developed for crowd counting can be applied to related tasks in other fields of study such as cell microscopy, vehicle counting and environmental survey. The task of crowd counting and density map estimation is riddled with many challenges such as occlusions, non-uniform density, intra-scene and inter-scene variations in scale and perspective. Nevertheless, over the last few years, crowd count analysis has evolved from earlier methods that are often limited to small variations in crowd density and scales to the current state-of-the-art methods that have developed the ability to perform successfully on a wide range of scenarios. The success of crowd counting methods in the recent years can be largely attributed to deep learning and publications of challenging datasets. In this paper, we provide a comprehensive survey of recent Convolutional Neural Network (CNN) based approaches that have demonstrated significant improvements over earlier methods that rely largely on hand-crafted representations. First, we briefly review the pioneering methods that use hand-crafted representations and then we delve in detail into the deep learning-based approaches and recently published datasets. Furthermore, we discuss the merits and drawbacks of existing CNN-based approaches and identify promising avenues of research in this rapidly evolving field.
Article
Full-text available
El estudio de animación Pixar Animation Studios ha sido el creador de 21 largometrajes animados por computadora (hasta 2019) como Monsters Inc., Intensa-Mente, Buscando a Nemo, la saga de Toy Story, entre muchas otras. Estas han impactado a varias generaciones gracias a sus historias, a la gran variedad de emociones que provocan, a sus personajes entrañables y a esos mundos increíbles que han desarrollado. La creación de cada una de estas películas lleva mucho tiempo y el trabajo de muchas personas en distintos departamentos como de arte, diseño de personajes, guión, animación, entre muchos otros; pero hay uno en especial que es de vital importancia, la tecnología: Tal vez te sorprenda la cantidad de tecnología que fue necesaria para hacer [las películas] posibles. De hecho, Pixar es en gran parte responsable de algunos de los desarrollos más significativos en gráficos por computadora de la historia. Muchas personas miran el producto y creen que sólamente es el arte, pero no entienden lo que hubo detrás. Es una combinación de arte y tecnología lo que hace que una película sea realidad. (Evers, 2019, 0:32, traducción propia). De esta manera, el objetivo de esta monografía es exponer la evolución e innovación de la tecnología de los gráficos por ordenador en los largometrajes animados a partir de Toy Story. Esta monografía es importante ya que mostrará algunos de los avances tecnológicos en diversos aspectos como renderizado, iluminación, simulaciones, softwares 3D, entre muchos otros, que se han desarrollado en el transcurso de los años en Pixar y así demostrar que la tecnología está fuertemente ligada con la animación. Asimismo, cómo es que cada historia requiere un reto tecnológico más grande y comunicar el proceso, las técnicas y los detalles en los que llegaron a cumplirlo mediante un lenguaje comprensible a todo lector. Es necesario incentivar a los jóvenes y a las personas en general en investigar cómo es que la tecnología ha cambiado sus vidas: no sólo en ejemplos comunes como un teléfono o una computadora, sino, en algo que ellos no esperarían: el entretenimiento; para así poder contribuir en un futuro a su desarrollo.
Article
Pedestrian counting from unconstrained images is an important task in various applications such as resource management, transportation engineering, urban design, and advertising, but it is greatly challenged by some factors such as interocclusion, cross‐scene, scale, and scene perspective distortion. Traditional image‐based methods suffer from them, and the performance of conventional sensor‐based methods such as Kinect and LASER degrades gradually with the increase in pedestrian count and distance from the device to pedestrians. Based on these challenges, this paper proposes a new network model making use of stacked multicolumn convolutional neural networks (CNNs) for pedestrian counting. The human's head features are used to replace the whole body for solving the problem of serious occlusion and choose multicolumn CNNs for dealing with scale and scene perspective distortion. Also, pretrained VGG‐16 is used to generate deeper detailed features and expand the receptive field of the model. Extensive analysis and experiments on current major pedestrian counting datasets show that the proposed network model has considerable advantages in pedestrian counting tasks compared to other state‐of‐the‐art models, and the proposed network model has an improvement effect for the training process. Moreover, the visual differences between the generated density map and ground‐truth density map are visualized and analyzed quantitatively to demonstrate the feasibility of the model.
Conference Paper
In Epic (2013), crowds are integral to the narrative and form a character as a whole. This required a new type of crowd at Blue Sky Studios, one that permits dynamic interaction between crowd characters and the environments around them in addition ...
Article
Visual representations of traffic flow and density in 3D city models provide substantial decision support in urban planning. While a large repertoire of efficient techniques exists for visualizing the static components of such environments (e.g., digital ...
Article
A new architecture for controlling mobile robots is described. Layers of control system are built to let the robot operate at increasing levels of competence. Layers are made up of asynchronous modules that communicate over low-bandwidth channels. Each module is an instance of a fairly simple computational machine. Higher-level layers can subsume the roles of lower levels by suppressing their outputs. However, lower levels continue to function as higher levels are added. The result is a robust and flexible robot control system. The system has been used to control a mobile robot wandering around unconstrained laboratory areas and computer machine rooms. Eventually it is intended to control a robot that wanders the office areas of our laboratory, building maps of its surroundings using an onboard arm to perform simple tasks.
Project Website: http://bulletphysics.org/wordpress
  • Bulletphysics
  • Org
Headstrong, hairy, and heavily clothed: Animating crowds of scotsmen
  • P Kanyuk
  • L J W Park
  • E Weihrich
Company Website: http://sidefx
  • Sidefx