jAER FAQ

jAER FAQ

Where is specific help for using the DVS128 dynamic vision sensor silicon retina?

See the specific guide for use of the DVS128 silicon retina.

Does jAER work under Windows 7?

Yes, under 32 bit it works perfectly. You will need to accept the installation of unsigned drivers. Under Windows 7 64 bit you will need to boot in kernel debug mode to disable signed driver check, in order to install the unsigned USB drivers. We have not yet purchased the necessary Authenticode code signing certificate. Hit F8 repeatedly during boot to get to the screen where you can select the option to "Disable Driver Signature Enforcement". As long as you boot in this mode, you should be able to use the DVS128 under Win7/64.

Does jAER work under linux?

Linux is fully supported through the libusb library-based interface.

Does jAER work under MacOS X?

There is a new experimental libUSB driver available as of 2013.

How can I use jAER?

If you want to work with hardware, you need a device, such as a temporal contrast retina or a monitor/sequencer board. Otherwise you can view and process data files.

My Tmpdiff128/DVS128 retina doesn't work.

You probably didn't load a set of bias values. Biases are stored in the biasgenSettings folder at the root of jAER. Plug in the retina, click on the Biasgen button at the lower left corner of AEViewer, then use the File/Load settings... menu item to choose a bias settings file, say tmpdiff128.xml. You may need to load this file several times because of a long standing bug with loading bias settings that change a lot of biases. For more information, see the Tmpdiff128 User Guide

How do I add my AER chip to jAER?

See "Adding a new chip"

How can I write my own custom event processor?

See "Adding a new event filter"

How do I add a custom DisplayMethod for my chip?

See, for example, the class ch.unizh.ini.caviar.chip.cochlea.CochleaChip. This superclass of cochlea chips adds several DisplayMethod's for displaying rasters of spikes, cross correlograms, etc.

Are there some sample data files available?

Yes, see the AER Data page.

Where are jAER program log files written and how is logging configured?

Logging of debugging and exception output (not AER data output) is configured by Logging.properties in jAER/trunk/conf. By default log files are written to jAER.log in the default temporary directory, e.g.

C:\Documents and Settings\tobi\Local Settings\Temp.

Where are program/filter/biasgen preferences stored?

All program preferences are stored using Java's Preferences mechanism (these preferences are stored in the Windows registry). Elements of jAER, like the bias generator bias values, can be exported to XML files. Bias values are stored on a node based on the Chip class, so there will not be name conflicts as long as the Chip's are in different java packages.

How can I set up Windows so that double-clicking an AE data file (.dat) opens JAERViewer and starts playing the file?

Right click a .dat file and choose "Open with..." and then "Choose program...". Then select the jAERViewer.exe launcher (make sure you choose the jAERViewer.exe and not jAERViewer.cmd). Now when you double-click the .dat file, the viewer should start and it should start playing the data file.

How can I generate javadoc for the source code?

We don't commit the javadoc because it changes so often and because it is big, but you can see an online snapshot of the javadoc which is probably out of date. You can build the javadoc in netbeans by right clicking on the project root in the Projects pane and selecting Generate javadoc for project. This should build the javadoc and show it in the browser - if not, let us know with a bug report.

How can I report bugs and ask for features?

Use the Trackers for the jAER project.

Can I use a 5V chip with the USB2AERmini2 board?

See this post: https://sourceforge.net/forum/forum.php?thread_id=1755625&forum_id=631958

How are preferences handled by EventFilter's and Biasgen's?

Event processing filters like BackgroundActivityFilter have parameters, as do Chip objects with bias settings. These are stored as user Preferences using nodes based on java package names.

It is possible to enclose a FilterChain of filters inside another EventFilter. In this case, the preferences for the enclosed filters are stored in a different node of the Preferences userRoot tree based on the enclosing EventFilter class. That way filters can have distinct Preference values.

Biasgen preferences are stored in a node of the Preferences tree based on the enclosing Chip object; that way there are no possible name conflicts for bias values as long as the Chip objects are in different java packages.

Rendering has suddenly gotten very slow, what's going on?

The left/right arrow keys control rendering rate. Probably you used the left arrow key. The achieved/target rendering rate in frames/sec (FPS) is shown in the status bar, e.g. 53/60fps. Use the right arrow key to increase to a reasonable desired rate, e.g. 30 or 60fps.

How can I make videos from jAER?

You can write PNG image sequences from the File/Write image sequence menu item (shortcut Ctl-Alt-M to start and stop) and then assemble a video using Macromedia Flash or Adobe Premiere, for example. Or try using the amazing Fraps (http://www.fraps.com), which writes uncompressed AVIs at full frame rate directly from an OpenGL surface like the ChipCanvas (you will need to postprocess the fraps video to recode it in order to view the video on a machine without the fraps codec installed - see the fraps page). Neither method captures the statistics header, however, because this header is rendered using Swing, not OpenGL.