Transcript
Setting up Multiple USB3 Cameras Revised 1/31/2017 Applicable Products Application Note Description FLIR USB 3.1 Technology Configure Drivers Bandwidth Allocation Device Link Throughput Limit—GenICam Format 7 Packet Size—IIDC Calculating Required Bandwidth Multiple Camera System Configurations Multiple Cameras Connected Directly to a USB 3.1 Host Controller Multiple Cameras Connected via a USB 3.1 Hub Multiple Cameras Connected to Multiple Host Controllers Troubleshooting Enumeration Link Recovery Errors Skipped Image Frames Low Frame Rate Downloads and Support Finding Information Contacting Technical Support
Names and marks appearing on the products herein are either registered trademarks or trademarks of FLIR Systems, Inc. and/or its subsidiaries. © 2012-2017 FLIR Integrated Imaging Solutions Inc. All rights reserved.
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TAN2012005—Setting up Multiple USB3 Cameras
Applicable Products FLIR USB 3.1 machine vision cameras
Application Note Description This application note explores multiple USB 3.1 camera configurations. The purpose of this document is to provide a reference and a starting point for USB 3.1 camera users who wish to use multiple USB 3.1 cameras in their application.
FLIR USB 3.1 Technology The type of data transfer that our USB 3.1 cameras use is bulk transfer. When factoring in the related overhead, the effective bandwidth is approximately 450 MB/s. Our USB 3.1 implementation uses image buffering to improve multiple camera system reliability and ensure data integrity. Packet Retransmission Our USB 3.1 cameras use a type of data transfer called bulk transfer. This type of transfer guarantees delivery and retransmits corrupt data packets, recovering from data errors when they occur. Data Buffer Our USB 3.1 cameras have a data buffer that allows images to be temporarily queued in the camera after readout. The main advantage of the data buffer is that it allows the system to handle momentary slowdowns on the bus without dropping any data. If the overall data throughput drops below requested data rate for an extended period of time, the camera can send entire uncorrupted frames out slower, and drop entire frames cleanly, rather than drop partial frames and cause image data errors. USB 3.1 link layer IP We have implemented our own USB 3.1 link layer technology in the camera FPGA. This allows us to introduce new functionality and ensure compatibility with third party hardware. USB3 Vision Standard Our USB 3.1 cameras comply with the USB3 Vision standard. USB3 Vision is a communication interface for vision applications based on the USB 3.1 technology. All cameras supporting USB3 Vision interact the same way ® with software also supporting USB3 Vision. The Spinnaker SDK uses GenICam to support the USB3 Vision standard. For more information on the USB3 Vision standard, see visiononline.org.
1/31/2017 ©2012-2017 FLIR Integrated Imaging Solutions Inc. All rights reserved.
Setting up Multiple USB3 Cameras
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TAN2012005—Setting up Multiple USB3 Cameras
Configure Drivers FLIR sells three USB 3.1 host controller cards: two based on the FL1100 chipset from Fresco and the µPD720200 chipset from Renesas. In addition to the manufacturer drivers, we recommend using the PGRUSBCam driver. For a list of compatible chipsets, see TAN2011005 Recommended USB 3.1 System Components. ®
With SpinView (for Blackfly S) or our driver control utility, you are able to identify the driver you are using and easily switch between them. Select the Point Grey Driver from the driver selection window.
Bandwidth Allocation USB 3.1 does not automatically manage bandwidth allocation. To help users accommodate multiple cameras on a single bus, we use a camera attribute which limits peak data bandwidth. This can be used to reduce the amount of data coming from each camera, preventing skipped frames or connectivity issues.
Device Link Throughput Limit—GenICam Use the device throughput limit feature to verify your system’s bandwidth limit, ensure your total bandwidth use is within that limit, and adjust your camera’s bandwidth accordingly. Consider the total of all the cameras on the system to calculate the required bandwidth. We recommend that the bandwidth requirements be divided equally among the number of cameras used, for example—two cameras, each requiring half of the maximum bandwidth; three cameras, each requiring one third of the maximum bandwidth. In the figure below, we see that the device max throughput is 38768000 bytes per second (384 MB/s). The current device link throughput limit is 18320000 bytes per second (184 MB/s).
Format 7 Packet Size—IIDC Format 7 packet size provides the user with a mechanism to allocate bandwidth for a particular camera. Reducing the packet size lowers the camera’s maximum frame rate and limits the amount of bandwidth the camera can ® use. The packet size can be controlled in FlyCapture 2 or the IIDC registers. FlyCap2 can be used to determine the bandwidth allocated for a given packet size. Reduce or increase the packet size to ensure the total amount of bandwidth output by the camera(s) does not exceed system limits. In the figure below, we see that reducing the packet size to 22624 bytes limits the maximum frame rate to 55 FPS, assuming image size and pixel format stay the same.
1/31/2017 ©2012-2017 FLIR Integrated Imaging Solutions Inc. All rights reserved.
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TAN2012005—Setting up Multiple USB3 Cameras
Calculating Required Bandwidth To calculate your bandwidth requirements, use your required resolution, frame rate, and pixel format (bytes per pixel) in the following equation. Height x Width x Frame Rate x Bytes per Pixel = Bandwidth in MB For example: Camera model: FL3-U3-13S2M-CS Resolution: 1328 x 1048 Frame rate: 60 FPS Pixel format: Mono16 Bandwidth = 1328 x 1048 x 60 x 2 = 167 MB Pixel format Mono8/Raw8 Mono12/Raw12 Mono16/Raw16 RGB8 YUV411 YUV422 YUV444 Bytes per pixel
1/31/2017 ©2012-2017 FLIR Integrated Imaging Solutions Inc. All rights reserved.
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TAN2012005—Setting up Multiple USB3 Cameras
Multiple Camera System Configurations This section documents various configurations and scenarios that have been tested with USB 3.1 cameras. The hardware and software setup with each configuration is also documented.
Multiple Cameras Connected Directly to a USB 3.1 Host Controller The figure below illustrates 4 cameras running on a 4 port USB3 card with Fresco FL1100 host controller.
Test System Component
Description
CPU
Intel Core i-7 4790
Motherboard
ASUS Z97-PRO
RAM
8 GB
Host adapter
FLIR 4 Port USB 3.1 PCI Host Adapter (ACC-01-1202)
Cabling
FLIR 3-meter USB 3.1 Cable Type-A to Micro-B
Operating system
Windows 7 x64
Driver
PGRUSBCam Driver 2.7.3.18
Software
Test application based on FlyCapture2 Release 2.7.3.13 x64
Camera
Grasshopper®3 GS3-U3-23S6M
Camera firmware 2.11.3.0 We used a console test application to obtain the test result below. The test application configures each camera to run at high performance mode and verifies that there are no dropped images.
Test Results Pixel Format
Resolution
Frame Rate
GS3-U3-23S6M-C
Raw8
1920 x 1200
40
33120
92
GS3-U3-23S6M-C
Raw8
1920 x 1200
40
33120
92
GS3-U3-23S6C-C
Raw8
1920 x 1200
40
33120
92
GS3-U3-23S6C-C
Raw8
1920 x 1200
40
33120
92
Camera Model
Total bandwidth
1/31/2017 ©2012-2017 FLIR Integrated Imaging Solutions Inc. All rights reserved.
Packet Size Bandwidth (Bytes) (MB/s)
368 MB/s
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TAN2012005—Setting up Multiple USB3 Cameras
Using the configuration above, a total of 368 MB/s is transferred to the host from multiple cameras. Although the effective USB 3.1 bandwidth is approximately 450 MB/s, peak performance can vary, depending on how the USB3 host adapter card manages bandwidth.
Multiple Cameras Connected via a USB 3.1 Hub This configuration demonstrates free-running 2 and 3 cameras using a single USB 3.1 hub. A table is provided to demonstrate the frame rates achieved in each configuration. As shown from the results, the USB 3.1 hub used could not sustain a data rate of greater than 345 MB/s.
Test System Component
Description
CPU
Intel Core i-7 4770
Motherboard
ASUS Z87-EXPERT
RAM
8 GB
Host Adaptor
Onboard Intel USB 3.1 port
Hub
4-Port USB 3.1 Hub with Screw Locks and External Power Adapter (ACC-01-6000)
Cabling
FLIR 3-meter USB 3.1 Cable Type-A to Micro-B (ACC-01-2300)
Operating system
Windows 7 x64
Driver
PGRUSBCam Driver 2.7.3.18
Software
Test application based on FlyCapture2 Release 2.7.3.13 x64
Camera
Grasshopper®3 GS3-U3-23S6M
Camera firmware 2.11.3.0 Note: For further recommendations, please see TAN 2011005 Recommended USB 3.1 System Components.
Test Results—One camera connected to a hub Camera Model GS3-U3-23S6M-C
Pixel Format
Resolution
Frame Rate
Raw8
1920 x 1200
162
Total bandwidth
1/31/2017 ©2012-2017 FLIR Integrated Imaging Solutions Inc. All rights reserved.
Packet Size Bandwidth (Bytes) (MB/s) 48096
373 373 MB/s
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TAN2012005—Setting up Multiple USB3 Cameras
Test Results—Two cameras connected to a hub Pixel Format
Resolution
Frame Rate
GS3-U3-23S6M-C
Raw8
1920 x 1200
70
48096
161
GS3-U3-23S6M-C
Raw8
1920 x 1200
70
48096
161
Camera Model
Packet Size Bandwidth (Bytes) (MB/s)
Total bandwidth
322 MB/s
Test Results—Three cameras connected to a hub Pixel Format
Resolution
Frame Rate
GS3-U3-23S6M-C
Raw8
1920 x 1200
50
48096
115
GS3-U3-23S6M-C
Raw8
1920 x 1200
50
48096
115
GS3-U3-23S6M-C
Raw8
1920 x 1200
50
48096
115
Camera Model
Total bandwidth
Packet Size Bandwidth (Bytes) (MB/s)
345 MB/s
Using the configurations above, the total throughput ranges from 322 MB/s to 373 MB/s. Although the effective USB 3.1 bandwidth is approximately 450 MB/s, peak performance can vary depending on how the USB 3.1 host controller manages bandwidth.
1/31/2017 ©2012-2017 FLIR Integrated Imaging Solutions Inc. All rights reserved.
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TAN2012005—Setting up Multiple USB3 Cameras
Multiple Cameras Connected to Multiple Host Controllers The following configuration uses multiple host controllers to share the bandwidth for 15 cameras.
Test System Component
Description
CPU
Intel i7 4790 @ 3.8 GHz
Motherboard
ASUS Z97 Pro Z97-PRO BIOS 2205
RAM
8 GB 1333 MHz non-ECC memory
Hard Drive
500 GB Segate - 7200 RPM
Power Supply
500 W Thermtake PSU
Host Adaptor
2 x onboard Intel 9 series USB3 ports 1 x onboard ASMedia USB3 port 3 x quad channel quad port Fresco FL1100 USB 3.0 card
Host Adaptor Driver
Intel USB3.0 eXtensible Host Controller version 4.0.0.36 ASMedia XHCI 1.0 Controller version 1.16.23.0 Fresco USB3 Extensible Host Controller version 2.7.3.79
Cabling
15 x FLIR 3-meter USB 3.1 Cable Type-A to Micro-B (ACC-01-2300)
Operating system
Windows 7 x64
Driver
PGRUSBCam Driver 2.7.3.18
Software
Test application based on FlyCapture2 Release 2.8.3.1 x64
Camera
15 x Grasshopper®3 USB3
Camera firmware
See test results
Test Results—15 cameras connected to multple host controllers Camera Model
Pixel Format
Resolution
Frame Rate
Firmware
Bandwidth (MB/s)
GS3-U3-120S6M
Mono8
640 x 480
30
1.17.2.0
9
GS3-U3-120S6M
Mono8
1288 x 968
17
2.22.3.0
21
GS3-U3-120S6M
Mono8
1288 x 968
21
2.22.3.0
64
GS3-U3-120S6M
Mono8
1280 x 968
25
2.22.3.0
17
GS3-U3-91S6C
Raw8
1288 x 968
17
2.22.3.0
21
GS3-U3-91S6C
Raw8
1288 x 968
17
2.22.3.0
21
GS3-U3-91S6C
Raw8
1288 x 968
17
2.22.3.0
21
GS3-U3-91S6C
Raw8
1384 x 1032
45
2.22.3.0
64
GS3-U3-60QS6C
Raw8
1288 x 968
27
2.22.3.0
34
1/31/2017 ©2012-2017 FLIR Integrated Imaging Solutions Inc. All rights reserved.
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TAN2012005—Setting up Multiple USB3 Cameras
Pixel Format
Resolution
Frame Rate
Firmware
Bandwidth (MB/s)
GS3-U3-41C6M
Mono8
640 x 480
188
2.22.3.0
233
GS3-U3-41C6C
Raw8
1280 x 968
188
2.22.3.0
233
GS3-U3-41C6M
Mono8
1280 x 968
188
2.22.3.0
233
GS3-U3-41S4M
Mono8
1288 x 968
29
2.22.3.0
36
GS3-U3-41S4M
Mono8
1288 x 968
29
2.7.3.0
36
GS3-U3-15S5C
Raw8
1384 x1032
45
2.22.3.0
64
Camera Model
Total bandwidth *Bandwidth shared across multiple host controllers
1137 MB/s*
Troubleshooting Enumeration n
When using a USB 3.1 camera, ensure it is adequately powered by an external adapter.
n
Ensure the latest firmware and drivers are being used.
Link Recovery Errors n
The host controller enters a recovery state to recover from bit errors that it has detected. This is often caused by a long cable or a bad connection.
n
Use the same cables to ensure the performance of each camera is consistent. Shorter cables are also preferred for better reliability.
n
For more information, see TAN2011006 Diagnosing USB 3.1 Camera and Bus Errors.
Skipped Image Frames n
This happens when the host is too slow in receiving and acknowledging the data coming from the camera. It can be caused by a host system that is too busy or by having too much data on the USB 3.1 bus for the host to handle.
n
To view the number of skipped frames: o
In SpinView, see the Log Viewer.
o
In FlyCapture2, see the Camera Information panel.
n
To alleviate the issue, manually reduce the Format 7 packet size until the max frame rate is reduced and images are no longer being skipped.
n
Use a higher performance PC to ensure fewer frames are skipped.
1/31/2017 ©2012-2017 FLIR Integrated Imaging Solutions Inc. All rights reserved.
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TAN2012005—Setting up Multiple USB3 Cameras
Low Frame Rate n
To increase the frame rate: o
In SpinView, increase the Device Link Throughput Limit.
o
In FlyCapture 2, increase the Format 7 packet size.
n
Ensure the PCI Express bus is 2.0 compliant. If a PCI Express 1.0 bus is used, the effective bandwidth (and hence frame rate) is reduced by half.
n
Ensure images frames are not being skipped. Please refer to the Skipped Image Frames section above for more information.
n
For more information, see KB 10108 My USB 3.1 camera does not achieve full frame rate.
Downloads and Support FLIR endeavors to provide the highest level of technical support possible to our customers. Most support resources can be accessed through the Support section of our website. The first step in accessing our technical support resources is to obtain a Customer Login Account. This requires a valid name and email address. To apply for a Customer Login Account go to our Downloads page. Customers with a Customer Login Account can access the latest software and firmware for their cameras from our website. We encourage our customers to keep their software and firmware up-to-date by downloading and installing the latest versions.
Finding Information FlyCapture SDK—The FlyCapture SDK provides API examples and the FlyCap camera evaluation application. Available from our Downloads page. API Documentation—The installation of the FlyCapture SDK comes with API references for C++, C#, and C code. Available from Start Menu→All Programs→Point Grey FlyCapture2 SDK→Documentation Product Documentation—The camera's Getting Started Manual provides information on installing components and software needed to run the camera. The Technical Reference provides information on the camera’s specifications, features and operations, as well as imaging and acquisition controls. They are available from the Downloads page. Knowledge Base—A database of articles and application notes with answers to common questions as well as articles and tutorials about hardware and software systems. Available from our Knowledge Base. Learning Center—Our Learning Center contains links to many resources including videos, case studies, popular topics, other application notes, and information on sensor technology.
1/31/2017 ©2012-2017 FLIR Integrated Imaging Solutions Inc. All rights reserved.
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TAN2012005—Setting up Multiple USB3 Cameras
Contacting Technical Support Before contacting Technical Support, have you: 1. Read the product documentation? 2. Searched the Knowledge Base? 3. Downloaded and installed the latest version of software and/or firmware? If you have done all the above and still can’t find an answer to your question, contact our Technical Support team.
1/31/2017 ©2012-2017 FLIR Integrated Imaging Solutions Inc. All rights reserved.
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