My team has always had horrendous cameras and I’m trying to fix that. We use a Raspberry PI with FRCVision for a coprocessor and have been using the lifecams with horrible results. Streams are laggy and slow with 15fps max. We are using a super low resolution and still have bad luck. What cameras do others use that perform well and at what resolution and FPS.
Changing cameras isn’t going to increase the bandwidth limit. You should focus your efforts on compression and reducing lag over stream quality. Remember, you only have 4 Mbps for all communication between the driverstation and the robot! It’s a tiny amount of data, and even then its inconsistent on the field.
Using extremely low resolutions helps a ton (talking 140p) as the video is still coherent while reducing the bandwidth required by a ton. Making the stream greyscale is a major improvement too. Also make sure you are only streaming one video at a time. Two cameras takes up twice the data. If you have a limelight or similar, double check it is not streaming data back to the driverstation.
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USB Cameras have a small latency issue because they are running over USB. The raspberry pis are great for cameras, but they are better if you use the pi’s camera port.
That is not my problem, I am the programmer and also the driver for my team and I see people with good resolution as well as super low latency and I cannot achieve that. We have noticed a huge difference depending on what cameras I use and I’d like to know of some good options for cameras.
Is the PICam a good option? I’ve seen some of those and could easily pick one up for my team.
Our team used the pi cam this year for our vision, and for any skill level of team its a good option. The pi camera is fragile though, so a casing is virutally required. Also the length of the cable is something to look out for as well, don’t expect long cable runs.
I use the PI Cams in my home for my 3D printer and have a case already designed for them. I’ll check them out for our robot. How would you discover them in the FRCVision OS?
I am not a software guy, so take what I am about to say with a boulder sized grain of salt. I don’t know FRCVision OS, all I’ve used is WPI’s premade pi camera OS, which I believe is the camera server. The camera stream goes over the network to network tables, in which you do whatever you want with it there.
Interesting, thanks. FRCVision is the WPILIB camera os.
The short answer is that they have better compression techniques. The camera isint going to matter if the data never gets compressed to a workable size back to the driver station, youll be stick at 100p no matter what camera you use.
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Ok, thanks! How exactly is compression done except within the Shuffleboard? I usually use the MJPEG streamer, what I use at home for my 3D printer enclosure as well.
While it’s received some really tough reviews lately due to it’s lack of stock, the limelight is a really nice camera if you have the ability to get your hands on it. Not only is it super easy to set up, it has been sending back consistently 89+ fps for us. My favorite part is its amazing documentation. I was able to put a kid with no programming knowledge on it for 30 minutes, and with minor help he got vision up and running. Even though its easy, he didn’t lose out on many of the concepts behind what machine vision attempts to do, which was important to me.
Issue is, it’s tough to get right now.
The limelight was a thought but it is hard enough to get my school to order a computer because programmers don’t need computers right… These cameras however were more driver cam oriented.
I have been trying to work with some of the newer RPi options that have been shown on CD such as Chamelion-Vision. In the docs they recommended a PS3 eye camera. I looked on amazon and they were only $7 so I gave one a try and the FPS went from 15-30 with a Microsoft Lifecam to >60 with the PS3 Eye.
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Just received the PI-Cams and they work wonders! Thanks!
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For anyone stumbling upon this thread, here’s a similar discussion from a while ago:
And my post within it, which I would copy here and suggest OP read.
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no problem!
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