Open API Standards for Mobile Graphics, Compute and Vision Processing GTC, March 2014

Transcription

1 Open API Standards for Mobile Graphics, Compute and Vision Processing GTC, March 2014 Neil Trevett Vice President Mobile Ecosystem, NVIDIA President Khronos Copyright Khronos Group Page 1

2 Khronos Connects Software to Silicon Open Consortium creating ROYALTY-FREE, OPEN STANDARD APIs for hardware acceleration Defining the roadmap for low-level silicon interfaces needed on every platform Graphics, compute, rich media, vision, sensor and camera processing Rigorous specifications AND conformance tests for crossvendor portability Acceleration APIs BY the Industry FOR the Industry Well over a BILLION people use Khronos APIs Every Day Copyright Khronos Group Page 2

3 Khronos Standards 3D Asset Handling - 3D authoring asset interchange - 3D asset transmission format with compression Visual Computing - 3D Graphics - Heterogeneous Parallel Computing Camera Control API Sensor Processing - Vision Acceleration - Camera Control - Sensor Fusion Over 100 companies defining royalty-free APIs to connect software to silicon Acceleration in HTML5-3D in browser no Plug-in - Heterogeneous computing for JavaScript Copyright Khronos Group Page 3

4 The OpenGL Family OpenGL 4.4 is the industry s most advanced 3D API Cross platform Windows, Linux, Mac, Android Foundation for productivity apps Target for AAA engines and games The most pervasively available 3D API 1.6 Billion devices and counting Almost every mobile and embedded device inc. Android, ios Bringing proven desktop functionality to mobile JavaScript binding to OpenGL ES Enabling the Web with GPU access Almost pervasive availability on mobile and desktop browsers Truly portable 3D apps with HTML5 Copyright Khronos Group Page 4

5 OpenGL ES 3.1 Launched at GDC! Headline features - Compute Shaders and Draw-Indirect - Compute shaders can create geometry or other rendering data Expecting rapid adoption - driver upgrade for many SOCs - Backward compatible with 2.0/3.0 so apps can incrementally adopt features Enabling desktop OpenGL to be used for mobile development - ARB_ES_3_1_compatibility specification to support OpenGL ES 3.1 context 2002 Working Group Formed Driver Update Silicon Update Silicon Update Driver Update Copyright Khronos Group Page 5

6 OpenGL Fallacy: Old and Inefficient Immediate Mode Fixed Function Display Lists Evaluators Feedback Ancient crufty stuff Selectors Selection Copyright Khronos Group Page 6

7 OpenGL Reality: Modern & Efficient Bindless ARB Multi-Draw Indirect GL4.3 Texture Arrays GL3.0 Buffer Storage GL4.4 SSBO GL4.3 UBO GL3.1 Copyright Khronos Group Page 7

8 Classic OpenGL Model Memory indirect draw CPU cmd cmd cmd cmd GPU texture object texture object Direct Drawing Commands (via the command fifo) render target Copyright Khronos Group Page 8

9 Efficient OpenGL Model CPU CPU CPU CPU Memory indirect draw indirect draw texture object indirect draw texture object Memory access mediated through OpenGL fences GPU CPU Writes Memory multi-threaded (no API)! render target GPU Writes Commands to Memory Reads Commands from Memory No API Minimal CPU Involvement Copyright Khronos Group Page 9

10 Results OpenGL enables scalable multi-threading with no new API - CPU and GPU Cores just write to memory - GPU work creation - builds buffers, constructs MDI commands Integer multiple speedups ~5x ~15x (not a typo) - On driver limited cases, obviously Works TODAY on existing drivers! - Mostly OpenGL Extensions are at least EXT Does not require a new object model - Does not require breaking existing applications Copyright Khronos Group Page 10

11 EGL 1.5 Released EGL 1.5 brings functionality from multiple extensions into core - Increased reliability and portability EGLImages - Sharing textures and renderbuffers Context Robustness - Defending against malicious code EGLSync objects - Improved OpenGL /OpenCL interop Platform extensions - Standardized interactions for multiple OS e.g. Android and 64-bit platforms srgb colorspace rendering NEXT EGLStreams into core for vision and camera interop API Interop EGL provides efficient transfer of data and events between Khronos APIs Applications OS and Display Platforms Application Portability EGL abstracts graphics context management, surface and buffer binding and rendering synchronization Copyright Khronos Group Page 11

12 OpenCL as Parallel Compute Foundation 100+ tool chains and languages leveraging OpenCL - Heterogeneous solutions emerging for the most popular programming languages C++ AMP Shevlin Park Uses Clang and LLVM Halide Image Processing Language WebCL JavaScript binding to OpenCL Aparapi Java language extensions for parallelism River Trail Language extensions to JavaScript PyOpenCL Python wrapper around OpenCL Harlan High level language for GPU programming Compiler directives for Fortran C and C++ OpenCL provides vendor optimized, cross-platform, cross-vendor access to heterogeneous compute resources Device X Device Y Device Z Copyright Khronos Group Page 12

13 Widening OpenCL Ecosystem OpenCL C Kernel Source Alternative Alternative Alternative Language for Language for Language Kernels for Kernels Kernels High-level High-level Apps Frameworks and Frameworks Frameworks SPIR Generator (e.g. patched Clang) SPIR Standard Portable Intermediate Representation SPIR 1.2 Released January 2014 OpenCL run-time can consume SPIR OpenCL C Runtime SYCL Programming abstraction that combines portability and efficiency of OpenCL with ease of use and flexibility of C++ SPIR 1.2 Released here at GDC! Device X Device Y Device Z Copyright Khronos Group Page 13

14 WebCL: Heterogeneous Computing for the Web WebCL 1.0 specification officially finalized today at GDC! - WebCL defines JavaScript binding to the OpenCL APIs - Enables initiation of Kernels written in OpenCL C within the browser Typical Use Cases - 3D asset codecs, video codecs and processing, imaging and vision processing - Physics for WebGL games, Online data visualization, Augmented Reality JavaScript Platform API To query, select and initialize compute devices GPU DSP HW OpenCL Kernel OpenCL Code Kernel OpenCL Code Kernel OpenCL C Code Kernel Code CPU CPU JavaScript Runtime API To build and execute kernels across multiple devices Copyright Khronos Group Page 14

15 WebGL/WebCL Ecosystem Content downloaded from the Web Middleware can make WebGL and WebCL accessible to non-expert programmers E.g. three.js library: used by majority of WebGL content Content JavaScript, HTML, CSS,... JavaScript Middleware Low-level APIs provide a powerful foundation for a rich JavaScript middleware ecosystem Browser provides WebGL and WebCL Alongside other HTML5 technologies No plug-in required JavaScript HTML5 / CSS OS Provided Drivers WebGL uses OpenGL ES 2.0 or Angle for OpenGL ES 2.0 over DX9 WebCL uses OpenCL 1.X Copyright Khronos Group Page 15

16 OpenVX Power Efficient Vision Acceleration Acceleration API for real-time vision - Focus on mobile and embedded systems Enable diverse efficient implementations - From CPUs, through GPUs and DSPs to dedicated hardware Foundational API for vision acceleration - Can be used by middleware libraries or by applications directly Complementary to OpenCV - Which is great for prototyping Khronos open source sample implementation - To be released with final specification - Sample - not reference - spec remains the definitive definition of OpenVX operation OpenCV open source library Open source sample implementation Application Other higher-level CV libraries Hardware vendor implementations Copyright Khronos Group Page 16

17 OpenVX Graphs The Key to Efficiency Vision processing directed graphs for power and performance efficiency - Each Node can be implemented in software or accelerated hardware - Nodes may be fused by the implementation to eliminate memory transfers - Processing can be tiled to keep data entirely in local memory/cache EGLStreams can provide data and event interop with other Khronos APIs - BUT use of other Khronos APIs are not mandated Native Camera Control OpenVX Node OpenVX Node OpenVX Node Example OpenVX Graph OpenVX Node Heterogeneous Processing Copyright Khronos Group Page 17

18 OpenVX 1.0 Function Overview Core data structures - Images and Image Pyramids - Processing Graphs, Kernels, Parameters Image Processing - Arithmetic, Logical, and statistical operations - Multichannel Color and BitDepth Extraction and Conversion - 2D Filtering and Morphological operations - Image Resizing and Warping Core Computer Vision - Pyramid computation - Integral Image computation Feature Extraction and Tracking - Histogram Computation and Equalization - Canny Edge Detection - Harris and FAST Corner detection - Sparse Optical Flow Widely used extensions adopted into future versions of the core OpenVX Specification Evolution OpenVX 1.0 defines framework for creating, managing and executing graphs Focused set of widely used functions that are readily accelerated Implementers can add functions as extensions Copyright Khronos Group Page 18

19 OpenVX and OpenCV are Complementary Governance Conformance Community driven open source with no formal specification No conformance tests for consistency and every vendor implements different subset Formal specification defined and implemented by hardware vendors Full conformance test suite / process creates a reliable acceleration platform Portability APIs can vary depending on processor Hardware abstracted for portability Scope Efficiency Very wide 1000s of imaging and vision functions Multiple camera APIs/interfaces Memory-based architecture Each operation reads and writes memory Tight focus on hardware accelerated functions for mobile vision Use external camera API Graph-based execution Optimizable computation, data transfer Use Case Rapid experimentation Production development & deployment Copyright Khronos Group Page 19

20 Vision Developers API Choice GPU Compute Shaders Flexible GLSL compute and imaging Easy to integrate into existing graphics apps Can mean less APIs and contexts for app to manage Limited to single GPU Out of the Box Vision Framework Vision operators and graph framework library Can run on dedicated hardware no compiler Suited for low-power, always-on acceleration Easier performance portability to diverse hardware General Purpose Heterogeneous Programming Framework Flexible, low-level access to any devices with OpenCL compiler Single run-time framework for CPUs, GPUs, DSPs, hardware Needs full compiler stack and IEEE precision Can be used to code new OpenVX nodes Copyright Khronos Group Page 20

21 Need for Camera Control API Advanced control of ISP and camera subsystem - Generate sophisticated image stream for advanced imaging & vision apps No platform API currently fulfills all developer requirements - Portable access to growing sensor diversity: e.g. depth sensors and sensor arrays - Cross sensor synch: e.g. synch of camera and MEMS sensors - Advanced, high-frequency per-frame burst control of camera/sensor: e.g. ROI - Multiple input, output re-circulating streams with RAW, Bayer or YUV Processing Scope of Camera Control API 3A - Auto Exposure (AE), Auto White Balance (AWB), Auto Focus (AF) Lens, sensor, aperture control Bayer Pre-processing Image Signal Processor (ISP) RGB/YUV Post-processing Image/Vision Applications Sensor, Color Filter Array Lens, Flash, Focus, Aperture Copyright Khronos Group Page 21

22 Camera API Architecture will be FCAM-based No global state - State travels with image requests - Every stage in the pipeline may have different state - Enables fast, deterministic state changes Synchronize devices - Lens, flash, sound capture, gyro - Devices can schedule Actions - E.g. to be triggered on exposure change Copyright Khronos Group Page 22

23 Low-level Sensor Abstraction API Apps request semantic sensor information StreamInput defines possible requests, e.g. Read Physical or Virtual Sensors e.g. Game Quaternion Context detection e.g. Am I in an elevator? Apps Need Sophisticated Access to Sensor Data Without coding to specific sensor hardware Sensor Discoverability Sensor Code Portability Advanced Sensors Everywhere Multi-axis motion/position, quaternions, context-awareness, gestures, activity monitoring, health and environmental sensors StreamInput processing graph provides optimized sensor data stream High-value, smart sensor fusion middleware can connect to apps in a portable way Apps can gain magical situational awareness Copyright Khronos Group Page 23

24 Khronos APIs for Augmented Reality AR needs not just advanced sensor processing, vision acceleration, computation and rendering - but also for all these subsystems to work efficiently together Audio Rendering MEMS Sensors Sensor Fusion Application on CPUs, GPUs and DSPs Precision timestamps on all sensor samples Vision Processing Advanced Camera Control and stream generation Camera Control API EGLStream - stream data between APIs 3D Rendering and Video Composition On GPU Copyright Khronos Group Page 24

25 NVIDIA Use of Khronos Standards Shipping - OpenGL OpenGL ES 3.X - WebGL OpenCL 1.X - EGL 1.4 Implementing - OpenVX 1.0 Provisional (foundational framework for VisionWorks) Participating - Camera Working Group - StreamInput Camera Control API Copyright Khronos Group Page 25