Synchronization issues with outdated PointGrey and Bonsai drivers

[Filipe Carvalho]

Dear Bonsai community,

I've posted this e-mail within Champalimaud Foundation institute regarding a recently discovered bug on the package Bonsai.PointGrey.

It brings the guidelines in order to have a perfect match between the corrected Bonsai.PointGrey (version 2.3.1) and the current PointGrey drivers.

I hope this can be also useful for the Bonsai awesome community.

Filipe

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Hi.

If you are using Bonsai and PointGrey cameras, we strongly suggest you to read this e-mail.

We would like to let you know how to proper set up your computer in order to have clean and smooth use of the PointGrey cameras.

=== Preamble / Useful Information ===

Bonsai 32 and 64 bits

Bonsai can be executed either in 32 bits (Bonsai.exe) or 64 bits (Bonsai (x64).exe). By default, when you open a Bonsai workflow, it will run at 32 bits.

The 64 bits instance of Bonsai gives you two big advantages: 1) is more efficient, i.e., it will do exactly the same job but using less CPU cycles, which gives more freedom for the CPU to execute other tasks and 2) has the ability to address more memory, i.e., specially if you are using high resolution and high speed cameras, you decrease the chances of getting an out-of-memory error.

So, why does Bonsai have a 32 bits version? Due to compatibilities. In order to interface with devices (PlayStation cameras, Haamatsus' photo-counters, ...) that don't provide 64 bits drivers.

PointGrey FlyCap Viewer

The drivers for the PointGrey cameras are installed when the FlyCap Viewer is installed on your computer. The cameras need these drivers to work properly.

FlyCap Viewer exist in both 32 and 64 bits.

=== Motivation ===

Support of Vivarium setups

Over the last months we were called to debug several setups using PointGrey cameras. The majority was not using the apropriate drivers for the cameras.

Bug

We've recently found a bug that affects who is using an external trigger to acquire frames (this is the approach that we recommend in order to get clean synchronization with data).

This bug is solved using a feature that is available only on the latest PointGrey drivers.

=== Guidelines for PointGrey and Bonsai ===

The goal is to unify the usage and dissipate possible issues that you may have (but don't know yet) on your setup.

1. Check your FlyCap Viewer version (you may need to check both 32 and 64 bits versions of FlyCap Viewer). Open FlyCap Viewer and check the version on the window Title Bar. If is equal to 2.11.3.425, jump to step 3. If not, go to next step.
2. Remove the current FlyCap Viewer from your computer (please notice that you may need to remove both 32 and 64 bits version). Reboot the computer.
   
3. Install these both versions. 32 bits and 64 bits. Reboot the computer.
4. On Bonsai. Make sure you are using the latest PointGrey package version 2.3.1. If not, update it.

And you are ready to go.

On Bonsai, we suggest that you use the attached code (change the FileName on the CsvWriter according your data folders). This will save the TimeStamp and FrameCounter of each frame. This will be extremely helpfully in order to synchronize the video and the data.

And, as always, if you have doubts or concerns, stop by the Hardware Platform's Office or send us an e-mail. We can help you if you would like to have support regarding this matter.

=== Acknowledges ===

Jonathan Tang for finding the bug.

Gonçalo Lopes for helping us with the Bonsai fix.

=== To conclude ===

The Harp tools have automatic ways to synchronize the PointGrey cameras with data.

I will send out an e-mail shortly explaining how.

Cheers,

Filipe Carvalho

Hardware Platform

Champalimaud Centre for the Unknown

Av. Brasilia

1400-038 Lisbon, Portugal

www.neuro.fchampalimaud.org