Search found 18 matches

by fraserbarton
Wed Oct 28, 2020 3:21 pm
Forum: OpenCV, Python and other image processing
Topic: Continuous Capture in the Background
Replies: 14
Views: 313

Re: Continuous Capture in the Background

As I understand it there are two modules in python, multiprocessing and multithreading, the first allow parallel execution and the second allows concurrent. When I originally asked the question I had looked at the two and thought that multiprocessing was more appropriate in this circumstance, althou...
by fraserbarton
Tue Oct 27, 2020 5:46 pm
Forum: OpenCV, Python and other image processing
Topic: Continuous Capture in the Background
Replies: 14
Views: 313

Re: Continuous Capture in the Background

Do you think that it is multithreading that would be appropriate in this case rather than multiprocessing?

I think I favour either of those as opposed to sockets and having to operate through an interface. Much easier to interact with objects directly.
by fraserbarton
Mon Oct 26, 2020 2:06 pm
Forum: OpenCV, Python and other image processing
Topic: Continuous Capture in the Background
Replies: 14
Views: 313

Re: Continuous Capture in the Background

Hello Fraserbaton and Stereomaton, Please let me jump into your discussion :-) In my point 1 of this answer , I attached a multithreaded Python code for the capture_continuous, and also added a link to the original related work at Pyimagesearch. Can this help you?.. Hi Realizator, In the context of...
by fraserbarton
Mon Oct 26, 2020 11:28 am
Forum: OpenCV, Python and other image processing
Topic: Continuous Capture in the Background
Replies: 14
Views: 313

Re: Continuous Capture in the Background

On a side note do you have any idea what would be a good starting point to work from in terms of designing an interface between the two pieces of software, one being the slave software that listens for requests for images and sends them back, the other being the master software that requests the ima...
by fraserbarton
Sun Oct 25, 2020 10:26 am
Forum: OpenCV, Python and other image processing
Topic: Continuous Capture in the Background
Replies: 14
Views: 313

Re: Continuous Capture in the Background

If I understand well, you want to have a part with blocking calls, and another independent that can respond during this, through probably another blocking call for the interface Could you elaborate what you mean by blocking call in this context? To my understanding they are to do with pausing execu...
by fraserbarton
Sun Oct 25, 2020 8:23 am
Forum: OpenCV, Python and other image processing
Topic: Continuous Capture in the Background
Replies: 14
Views: 313

Re: Continuous Capture in the Background

Hi steromaton, Apologies, this is not the actual code. I tried to break it down into a smaller example of the core processes so that it wouldn't be such a pain for someone else to have a look over. I understand that multiprocessing is not a trivial thing to achieve and for this reason I would probab...
by fraserbarton
Sat Oct 24, 2020 6:51 pm
Forum: OpenCV, Python and other image processing
Topic: Continuous Capture in the Background
Replies: 14
Views: 313

Continuous Capture in the Background

In my application I take a horizontal intensity profile of an array of sewing pins. My setup has a set of LEDs that are toggled on and off in between frame captures. The OFF scan is subtracted from the ON scan to reduce background noise, and therefore a full scan is only produced every two capture c...
by fraserbarton
Tue Jul 14, 2020 3:18 pm
Forum: OpenCV, Python and other image processing
Topic: Faster framerate
Replies: 9
Views: 3148

Re: Faster framerate

Hi Fraserbarton, I was trying to look inside camera work logic. At this moment I found, that actually you can get information about cirrent frame capture status using GPIO, originally intended for the camera LED. Here is the discussion . This scope requires a deep investigation, but I have a hypoth...
by fraserbarton
Thu Jul 02, 2020 11:55 am
Forum: StereoPi mechanics
Topic: StereoPi AnyCase Kit
Replies: 6
Views: 4963

Re: StereoPi AnyCase Kit

Hi Fraserbaton, Yep, the plywood drilling without splitting on the opposite side is a tricky thing. You can google for the details. ABS plastic is an expensive thing for DIY details. We are considering to use acrylic plastic (like for the camera mounting plates in our kits), but it also has some sp...
by fraserbarton
Tue Jun 30, 2020 1:54 pm
Forum: StereoPi mechanics
Topic: StereoPi AnyCase Kit
Replies: 6
Views: 4963

Re: StereoPi AnyCase Kit

We're developed a kit for the very quick case prototyping. You can assemble any case in a 10 minutes using just a screwdriver. You can find more details here: https://stereopi.com/anycase We'll upload a drawings to our Wiki in the nearest days. Hi, I have recently purchased an AnyCase kit. My appli...
by fraserbarton
Sun Apr 05, 2020 6:10 pm
Forum: OpenCV, Python and other image processing
Topic: Faster framerate
Replies: 9
Views: 3148

Re: Faster framerate

It's a quick answer without checking anything, but have you considered the capture_continuous function of picamera which seems to be more or less written for the kind of application you have: https://picamera.readthedocs.io/en/release-1.10/api_camera.html#picamera.camera.PiCamera.capture_continuous...
by fraserbarton
Sun Apr 05, 2020 9:32 am
Forum: OpenCV, Python and other image processing
Topic: Faster framerate
Replies: 9
Views: 3148

Re: Faster framerate

Hi Fraserbaton, While taking a still images Pi works in a special mode, and high FPS is a problem here. Another point is that raspividyuv actually can give you a high frame rate over pipe, but Python is unable to process this stream fast enough. Can you please tell me the background of your task? 1...
by fraserbarton
Thu Apr 02, 2020 7:06 pm
Forum: OpenCV, Python and other image processing
Topic: Faster framerate
Replies: 9
Views: 3148

Re: Faster framerate

Hi Michael93, Actually Python frames capture is a bottleneck. You can do some optimizations for this. For example, you can read this brilliant answer from the PiCamera developer here . I mean the second part of his answer concerning np.frombuffer section. You see, we're preparing a new article now,...
by fraserbarton
Wed Apr 01, 2020 12:54 pm
Forum: OpenCV, Python and other image processing
Topic: Capturing monochromatic images
Replies: 1
Views: 1012

Capturing monochromatic images

I am looking to capture monochromatic images for my project and am wondering of the best way to achieve this. At the moment I am capturing RGB output from the camera into a numpy array and then getting a grayscale image by performing a dot-product of the RGB matrix with an RGB to grayscale conversio...
by fraserbarton
Mon Mar 30, 2020 3:45 pm
Forum: OpenCV, Python and other image processing
Topic: Broken Stereoscopic Support in Raspbian Stretch
Replies: 4
Views: 1686

Re: Broken Stereoscopic Support in Raspbian Stretch

Apologies I was using the -3d option incorrectly, that makes sense that it would require an option like side by side or top and bottom. Although when I do pass the sbs option the preview window just freezes over the top of raspbian so it is more likely to be this kernel issue. I had tried to use the...
by fraserbarton
Mon Mar 30, 2020 11:41 am
Forum: OpenCV, Python and other image processing
Topic: Broken Stereoscopic Support in Raspbian Stretch
Replies: 4
Views: 1686

Broken Stereoscopic Support in Raspbian Stretch

I am currently experiencing issues with the stereoscopic mode, I am running Raspbian stretch and Python 3.5.3. If I run raspistill -cs 0 or raspistill -cs 1 I get the preview from either camera happily. Running raspistill to bring up the various options I can pass, I can see that -3d is listed. Howe...
by fraserbarton
Wed Oct 09, 2019 11:38 am
Forum: StereoPi hardware
Topic: Powering StereoPi via 40 way GPIO Header
Replies: 5
Views: 2564

Re: Powering StereoPi via 40 way GPIO Header

Hi Fraserbarton, To say briefly, pins 2 and 4 are sitting on the same line as +5V pin on power connector, as shown on this picture: https://wiki.stereopi.com/images/thumb/8/82/Stereopi-usb-power-pinout.png/1200px-Stereopi-usb-power-pinout.png This is correct if power switch is turned On. So you can...
by fraserbarton
Sun Oct 06, 2019 12:12 pm
Forum: StereoPi hardware
Topic: Powering StereoPi via 40 way GPIO Header
Replies: 5
Views: 2564

Powering StereoPi via 40 way GPIO Header

Does anyone know if it is possible to power the StereoPi from the 40 way GPIO header? I want my Pi to be powered from 24V and was intending on putting a 5V switching regulator on an external board to supply the Pi and some other high IO. It would make my design much more refined If I can just take t...