A Comparison of Intel® RealSense™ Front Facing Camera SR300 and F200

Introduction

The SR300 is the second generation front-facing Intel® RealSense™ camera that supports Microsoft Windows* 10. Similar to the F200 camera model, the SR300 uses coded light depth technology to create a high quality 3D depth video stream at close range. The SR300 camera implements an infrared (IR) laser projector system, Fast VGA infrared (IR) camera, and a 2MP color camera with integrated ISP. The SR300 model uses Fast VGA depth mode instead of native VGA depth mode that the F200 model uses. This new depth mode reduces exposure time and allows dynamic motion up to 2m/s. This camera enables new platform usages by providing synchronized color, depth, and IR video stream data to the client system. The effective range of the depth solution from the camera is optimized from 0.2 to 1.2m for use indoors.

Figure 1: SR300 camera model.

The SR300 camera can use the Intel® RealSense™ SDK for Windows. The version that adds support for SR300 is SDK 2015 R5 or later. The SR300 will become available and built into form factors in 2016 including PCs, all-in-ones, notebooks and 2-in-1s. The SR300 model adds new features and has a number of improvements over the F200 model as follows:

• Support for the new Hand Tracking Cursor Mode
• Support for the new Person Tracking Mode
• Increased Range and Lateral Speed
• Improved Color Quality under Low-light Capture and Improved RGB Texture for 3D Scan
• Improved Color and Depth Stream Synchronization
• Decreased Power Consumption

* As of Feb 19^th, 2016.

New Features only Supported by SR300

Cursor Mode

The standout feature for the SR300 camera model is Cursor Mode. This tracking mode returns a single point on the hand allowing accurate and responsive 3D cursor point tracking and basic gestures. Cursor mode also improves power and performance more than 50% compared to Full Hand mode but without latency or requiring calibration. It also increases range to 85cm and tracks hand motion speed up to 2m/s. Cursor Mode includes the Click gesture to simulate the mouse click using the index finger.

Figure 2: Click gesture.

Person Tracking

Another new feature provided for the SR300 model is Person Tracking. Person Tracking also supports the rear facing camera R200, but is not available for the F200. Person Tracking supports real-time 3D body motion tracking. It has three main tracking modes: the body movement, skeleton joints, and facial recognition.

• Body movement: Locates the body, head and body contour.
• Skeleton joints: Return the position of body’s joints in 2D and 3D data.
• Facial recognition: Compares the current face against the database of registered users to determine the user’s identification.

Increased Range and Lateral Speed

The SR300 camera model introduces a new Depth mode called Fast VGA. It captures frames at HVGA but interpolates the frames to VGA before transmitting to a client. This new depth mode reduces exposure time for scenes and allows hand motion speed up to 2m/s while native VGA F200 support accepts hand motion speed only up to 0.75m/s. The SR300 model also provides a significant improvement in range from the F200 model. Using hand tracking, the SR300 was able to achieve up to 85 cm while the F200 only achieved 60 cm. Hand segmentation range is increased up to 110 cm for the SR300 improved from 100 cm for the F200 model.

The range for face recognition increases from 80 cm for the F200 up to 150 cm for the SR300 model.

The SR300 model improves RGB texture mapping and achieves a more detailed 3D scan. The range for 3D scan increases up to 70 cm while also allowing more details. Blob tracking speed increases up to 2m/s and its range increases up to 150 m/s in the SR300 model.

The depth range of the SR300 model was improved by 50%-60%. At the 80 cm range, both SR300 and F200 cameras detect the hand clearly. When the range gets longer than 120 cm, the SR300 can still detect the hand while F200 can’t detect the hand at all at that range.

Figure 3: SR300 vs F200 depth range.

Improved Color Quality Under Low-light Capture and Improved RGB Texture for 3D Scan

The new auto exposure feature is only available with the SR300 model. The exposure compensation feature allows the images taken in low-light or high-contrast to achieve better color quality. The color stream frame rate in the low-light condition might be lower when the color stream auto exposure is enabled.

Improved Color and Depth Stream Synchronization

The F200 model only supports multiple depth and color applications running at the same frame rate. The SR300 supports multiple depth and color applications running at different frame rates, within an integer interval, while maintaining temporal synchronization. This allows software to switch between different frame rates without having to start or stop the video stream.

Decreased Power Consumption

The SR300 camera model enables additional power gear modes that can operate at lower frame rates. This allows the image system to reduce the power consumption of the camera, but still maintains awareness. With the power gears mode, SR300 can process the scene autonomously while the system is in standby mode.

Backward Compatibility with F200 Applications

The Intel RealSense Depth Camera Manager (DCM) 3.x enables the SR300 camera to function as an F200 camera to provide backwards compatibility for applications developed for the F200 camera model. The DCM emulates the capabilities of the F200 camera so that the existing SDK applications can work seamlessly on the SR300 model. SR300 features are supported in SDK R5 2015 or later.

When a streaming request comes from an SDK application compiled with SDK earlier than SDK R5 2015, the DCM will automatically activate the compatibility mode and send calls through the F200 pipe instead of the SR300 pipe. Most applications should work without any configuration on the new SR300 model.

Infrared Compatibility

The SR300 supports a 10-bit native infrared data format while the F200 supports an 8-bit native infrared data format. The DCM driver will provide compatibility by either removing or padding 2-bit of the data to fit the requested infrared data size.

Physical Connector

The motherboard and cable design for F200 and SR300 are identical. The F200 cable plug fits into an SR300 receptacle. Therefore, an F200 cable can be used for an SR300 camera model. Both models require fully powered USB 3.0.

SDK APIs

Most SDK APIs are shared between SR300, F200 and even R200 in some cases, and the SDK modules provide the proper interface depending on the camera found at runtime. Similarly, simple color and depth streaming that does not call specific resolutions or pixel formats will run without change required.

And by using the SenseManager to read raw streams, no code change is needed to pick stream resolutions, frame rate, and pixel format without hardcoding.

For the above automatic change depending on camera, it’s important for every app to check for camera model and configuration at runtime. See Installer Options in the SDK documentation.

DCM

As of this writing, the gold DCM version for SR300 is DCM 3.0.24.59748 and updates will be provided by Windows Update. Visit https://software.intel.com/en-us/intel-realsense-sdk/download to download the latest DCM. For more information on the DCM, go to Intel® RealSenseTM Cameras and DCM Overview.

Hardware Requirements

To support the bandwidth needed by the Intel RealSense camera, a USB 3 port is required in the client system. For details on system requirements and supported operating systems for SR300 and F200, see https://software.intel.com/en-us/RealSense/Devkit/

Summary

This document summarizes the new features and enhancements available with the front-facing Intel RealSense 3D camera SR300 beyond those available with the F200. These new features are supported in SDK 2015 R5 and DCM 3.0.24.51819 or later. This new camera is available to order at http://click.intel.com/realsense.html.

Helpful References

Here is a collection of useful references for the Intel® RealSense™ DCM and SDK, including release notes and how to download and update the software.

• Developer Zone:
  https://software.intel.com/en-us/realsense/home
  https://software.intel.com/en-us/forums/realsense
• F200
  https://software.intel.com/en-us/articles/realsense-r200-camera
• DCM:
  https://software.intel.com/en-us/blogs/2015/10/18/intel-realsense-depth-camera-manager-dcm-overview?wapkw=DCM%20overview
• SDK
  https://software.intel.com/en-us/blogs/2016/01/28/new-realsense-v8

About the Author

Nancy Le is a software engineer at Intel Corporation in the Software and Services Group working on Intel® Atom™ processor scale-enabling projects.