Hello, not sure if this is the proper forum. I am a newbie here.
I am experimenting with a jetson nano as a robot controller. My robot is normally controlled with a regular PC and it would be interesting to control it with a much smaller and cheaper device.
I have a Sony A5100 camera connected via USB, and am controlling this camera with libgphoto2. It does work, in principle, but the download speed of preview and full resolution photos is low. On the PC i could get about 25 previews a second (the upper limit of the camera i think), on the nano only about 2. The previews are small (1024x680) .jpg files, on average 75KB large. I would expect to see a higher throughput!
Please run sudo tegrastats to get information about system loading.Not sure but probably the application takes much CPU loading, capping the performance. We have checked the USB3 bandwidth and it is good to achieve 5Gbps.
I’ve figured out a solution. Yesterday, when i ran the tests, i did so after installing the latest version of libgphoto2 (2.5.25). Today i was looking at debug messages from gphoto2 and there i saw that it was using version 2.5.16. I did not know that libgphoto2 was already installed on the nano, by default. The old version in /usr/lib/aarch64-linux-gnu had precedence over the latest version in /usr/local/lib. All my speed problems are solved by removing version 2.5.16 and using 2.5.25.
Downloading a live preview image now takes 10 to 15 ms, while it took about 320 ms before the update, a very significant change!