Bug with Pylon software (presumably) associated with the "Maximum Transfer Size"

[Aaron Allen]

Good afternoon,

 

I've recently come across your software and am excited to test it out on our system. Currently we only have a need for single camera recording, and recording directly to ufmf, so strand seems like it would fit the bill nicely. But do have hopes to expand to a few multi-camera setups in the future.

 

But we are running into an issue (presumably) with the Pylon software associated with the "Maximum Transfer Size" parameter. The issue may be solved by the proposed solution in another conversation regarding "Maximum Transfer Size" (https://groups.google.com/g/multicams/c/7oAWkhGGWAY), although I think our issue is slightly different.

 

When we launch the strand-camera application the preview video freezes almost immediately and starts dropping frames. The preview will then pop in and out. When we launch the Pylon Viewer software, we see the exact same behaviour while streaming the preview.

 

Our issue seems to be that, while in the Pylon Viewer software, no matter what the initial default value for "Maximum Transfer Size '' is, the camera will drop frames while trying to preview the stream. As mentioned in the other conversation, this value does not seem to be saved to the camera in the "User Set Control", and so always resets to a default, seemingly dictated by Pylon Viewer (and the OS). This frequently results in the software freezing and requiring an OS reboot, while using Ubuntu (and on Windows the occasional BSD). The streaming and recording from Pylon is perfectly fine if we either increase OR decrease the "Maximum Transfer Size '' parameter (this is how it seems to differ from the other conversation). The default value for this also seems to be different depending on the OS for which Pylon Viewer v6.1.1 is installed (262144 for Ubuntu 18.04, and 1048576 for Windows 10). In both OS cases, incrementing or decrementing the value, by as little as 4 bits, results in perfect recording. This suggests that there is nothing inherently wrong with the default value, but just that something needs to change to update something internally with the streaming parameters (..?..). I imagine a parameter (as suggested in https://groups.google.com/g/multicams/c/7oAWkhGGWAY) stop the stream, adjust the "Maximum Transfer Size '' parameter, and restart the stream would “solve” this issue, until something gets sorted out by Basler in their Pylon software.

 

I have tested this issue on multiple versions of pylon software on Ubuntu (pylon v5.1.0, v5.2.0, v6.1.1, v6.2.0, v6.3.0) and the issue is present in all cases. I have also tested this on both Ubuntu and Windows, and with 2 different models of USB3 cameras (acA1920-155um and acA2440-75um). Basler has yet to respond to any of my support question emails, but hopefully they will eventually… 

 

Thanks for your time, and I really hope something can get sorted out to solve this issue, as we’d really like to switch our recording setup over to your system.

 

Aaron.

[Andrew Straw]

Hi,

This is quite interesting - thanks for the info. That said, I can't add much to your report but the following minor points: First, I now understand that this is a "stream grabber" parameter and at the Pylon API level this is fairly significant in the sense that it is not a parameter from the the camera's own "node map" but rather from the "stream grabber node map". Presumably this explains why this parameter is not saved to the camera - it actually isn't a "camera parameter" at all. Secondly, I am tracking the issue of adding support to Strand Camera and Braid here: https://github.com/strawlab/strand-braid/issues/10 . I will update this thread and the other thread once I make a release where the MaxTransferSize parameter can be set. I hope I can manage in the next couple of days to cleanup my hacks and make a release with this.

Best,

Andrew

[Andrew Straw]

I think I fixed this as noted at the issue on GitHub and will be working on a new release which includes this fix.

[Aaron Allen]

Many thanks. I look forward to testing this out.

Aaron.

[Andrew Straw]

As you may see in the other thread, I just released Strand Camera and Braid version 0.11.0 on Github: https://github.com/strawlab/strand-braid/releases/tag/0.11.0 which set the MaxTransferSize to the maximum possible value upon startup. I'm interested to hear if this fixes things for you.

Best,

Andrew

[Aaron Allen]

Good afternoon, 

The fix in 0.11.1 regarding MaxTransferSize has solved my issue with frame rates and being able to record a video without dropping frames. 

Thank you very much.

Aaron.