Technical Application Note

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1 Technical Application Note Synchronizing a Blackfly or Grasshopper3 GigE Camera s Time to PC Time Technical Application Note TAN Revised July 4, Subject Technical Application Note (TAN ): 1.2 Applicable Product(s) Blackfly GigE cameras Grasshopper3 GigE cameras 1.3 Application Note Description This application note describes how to synchronize a Point Grey BFLY-PGE or GS3-PGE camera s internal time to system (PC) time. This is useful for users that need to find out when images are being captured relative to real world time. GigE Vision Timestamps Example Synchronization Method Additional Downloads and Support Point Grey logo, Spinnaker, FlyCapture, Digiclops, Blackfly, Dragonfly, Dragonfly Express, Chameleon, Firefly, Flea, Grasshopper, Ladybug, Scorpion, Zebra and Triclops are trademarks or registered trademarks of Point Grey in Canada and other countries Point Grey. All rights reserved.

1.4 GigE Vision Timestamps Point Grey s BFLY-PGE and GS3-PGE cameras support two timestamp values in each image transmission. 1. GigE Vision image leader timestamp 2.

2 1.4 GigE Vision Timestamps Point Grey s BFLY-PGE and GS3-PGE cameras support two timestamp values in each image transmission. 1. GigE Vision image leader timestamp 2. GigE Vision chunk data (by selecting timestamp as chunk data) Image Leader Timestamp GigE Vision image leader timestamp is automatically included at the image transmission level. Convert image leader timestamp to real world time as follows: Camera_time (ns) = Image_leader_timestamp (tick) * 8 (ns/tick) Wireshark Log Showing Image Leader Packet Contains Timestamp Revised 4-Jul-16 Copyright Point Grey Research, Inc. All rights reserved. 2

1.4.2 Chunk Data Timestamp GigE Vision chunk data timestamp can be

Enabling Chunk Image Timestamp in A&B Software s ActiveGigE Software

Camera_time (ns) = Chunk_image_timestamp (tick) * 8 (ns/tick) Wireshark

3 1.4.2 Chunk Data Timestamp GigE Vision chunk data timestamp can be enabled in any GigE Vision application. Enabling Chunk Image Timestamp in A&B Software s ActiveGigE Software Convert chunk image timestamp to real world time as follows: Camera_time (ns) = Chunk_image_timestamp (tick) * 8 (ns/tick) Wireshark Log Showing Chunk Image Timestamp Revised 4-Jul-16 Copyright Point Grey Research, Inc. All rights reserved. 3

Point Grey s BFLY-PGE and GS3-PGE cameras timestamp is based on an internal clock. The value of this internal clock can be retrieved by using the Latch Timestamp feature.

4 Point Grey s BFLY-PGE and GS3-PGE cameras timestamp is based on an internal clock. The value of this internal clock can be retrieved by using the Latch Timestamp feature. A&B Software s ActiveGigE Properties Page Convert latched timestamp to camera time as follows: Camera_time (ns) = Latched_timestamp (tick) * 8 (ns/tick) For every image, chunk image timestamp and leader timestamp should return an identical value: Chunk image timestamp (64-bit value) = Leader timestamp (64-bit value) Please note: Point Grey s FlyCapture1 and FlyCapture2 software does not support timestamp latch and chunk image timestamp. Revised 4-Jul-16 Copyright Point Grey Research, Inc. All rights reserved. 4

5 1.5 Example Synchronization Method In this example, we synchronize the camera s internal time with PC time by first obtaining an offset. Then, we take a sample image and convert the chunk image timestamp to PC time. The goal would be to find out when (according to PC time) each image is taken. For simplicity, we use the unit seconds for our calculation. Point Grey cameras support nanosecond resolution. Revised 4-Jul-16 Copyright Point Grey Research, Inc. All rights reserved. 5

First relate camera s internal clock to PC clock by obtaining the time offset. 1. Retrieve PC time (using Windows SYSTEMTIME struct) - Current PC time 10:00 am and 30 seconds 2.

Camera_time = 134005590072 tick * 8 ns/tick = 1072 seconds A&B Software s ActiveGigE Showing Latched Timestamp Value 3.

6 First relate camera s internal clock to PC clock by obtaining the time offset. 1. Retrieve PC time (using Windows SYSTEMTIME struct) - Current PC time 10:00 am and 30 seconds 2. Use camera to latch timestamp - Latched timestamp value = Use the formula below to convert latched timestamp to camera time Camera_time (ns) = Latched_timestamp (tick) * 8 (ns /tick) Camera_time = tick * 8 ns/tick = 1072 seconds A&B Software s ActiveGigE Showing Latched Timestamp Value 3. Calculate offset - 10:00 am and 30 second equal to seconds since midnight (12:00 am) - PC time seconds equates to camera time 1072 seconds Offset = PC_time (s) Camera_time (s) Offset = (s) 1072 (s)= (s) At this point, we know that if we retrieve the chunk image timestamp plus seconds, it is equal to our PC time relative to midnight. Revised 4-Jul-16 Copyright Point Grey Research, Inc. All rights reserved. 6

Next, for every image captured, decode either the leader timestamp or the chunk image timestamp. Then use the offset calculated from above to translate camera time to PC time.

7 Next, for every image captured, decode either the leader timestamp or the chunk image timestamp. Then use the offset calculated from above to translate camera time to PC time. A&B Software s ActiveGigE Showing Chunk Image Timestamp Value We capture an image with chunk timestamp enabled. Camera_time (ns) = Chunk_image_timestamp (tick) * 8 (ns/tick) Camera_time = * 8 (ns) = 1202 (s) The current PC time would be PC_time (s) = Camera_time (s) + Offset (s) PC_time (s) = 1202 (s) (s) = (s) seconds since midnight, which equates to 10:03 am. This sample image is taken at PC time 10:03 am. Revised 4-Jul-16 Copyright Point Grey Research, Inc. All rights reserved. 7

8 1.6 Additional Downloads and Support Point Grey Research Inc. 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. Creating a Customer Login Account The first step in accessing our technical support resources is to obtain a Customer Login Account. This requires a valid name and address. To apply for a Customer Login Account go to the Downloads page. Knowledge Base Our Knowledge Base contains answers to some of the most common support questions. It is constantly updated, expanded, and refined to ensure that our customers have access to the latest information. Product Downloads Customers with a Customer Login Account can access the latest software and firmware for their cameras from our Downloads page. We encourage our customers to keep their software and firmware up-to-date by downloading and installing the latest versions. Contacting Technical Support Before contacting Technical Support, have you: 1. Read the product documentation and user manual? 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. Revised 4-Jul-16 Copyright Point Grey Research, Inc. All rights reserved. 8

Technical Application Note

Technical Application Note 1.1 Subject Improvements to the Ladybug SDK v1.13 Technical Application Note TAN2014017 Revised May 9, 2016 Technical Application Note (TAN2014017): Improvements to the Ladybug