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by cpunk
Sat Oct 28, 2017 9:44 pm
Forum: Java
Topic: Code sample: rolling rainbow on APA102 LEDs from Java
Replies: 3
Views: 2918

Code sample: rolling rainbow on APA102 LEDs from Java

Since this bit took me a few hours to code, I thought I'd try to save time for others in case they try similar ventures. :) Basically, I got some APA102 LEDs and needed to implement blinking lights and a continuously rolling rainbow with them. The program needed to be in Java, as the rest of my syst...
by cpunk
Tue Aug 29, 2017 11:06 am
Forum: Camera board
Topic: Cheap RC airplane with "outboard" Pi Zero and camera
Replies: 45
Views: 30367

Re: Cheap RC airplane with "outboard" Pi Zero and camera

The lift of that thing in case of helium: approximately 1 g / L (or alternatively, kg / m3). With hot air, about 10 times less, maybe 0.1, as hot air is comparatively dense, not much lighter than ordinary air. As for volume, if we assume it's a cylinder, then volume = base area * height. Base area w...
by cpunk
Sun Aug 13, 2017 6:13 pm
Forum: Camera board
Topic: Cheap RC airplane with "outboard" Pi Zero and camera
Replies: 45
Views: 30367

Re: Cheap RC airplane with "outboard" Pi Zero and camera

The (fresh) water resistance of unprotected electronics is quite surprising sometimes (at low voltage?). :D But salt water does things quickly. I have once landed a foam glider in sea, and within the 7 seconds it took me to disconnect power, the receiver and motor controller had already conducted a ...
by cpunk
Thu Aug 10, 2017 12:50 pm
Forum: Camera board
Topic: Cheap RC airplane with "outboard" Pi Zero and camera
Replies: 45
Views: 30367

Re: Cheap RC airplane with "outboard" Pi Zero and camera

Quite impressive for such a small plane. :) I'm used to them blowing away with wind. :D
by cpunk
Thu Aug 10, 2017 9:50 am
Forum: Camera board
Topic: Camera Flicker Avoidance
Replies: 6
Views: 2463

Re: Camera Flicker Avoidance

Hello, Can you please confirm that your camera is working in normal mode (without this command line switch)? I added the command line option for flicker avoidance, and it was a simple userland change, no firmware was involved at all. Also, can you try if the short command line option (e.g. "-fli 50h...
by cpunk
Wed Aug 09, 2017 7:12 pm
Forum: Camera board
Topic: raspivid raw RGB data is incorrect?
Replies: 30
Views: 8320

Re: raspivid raw RGB data is incorrect?

Tested. :) Works beautifully. Thank you! :)
by cpunk
Wed Aug 09, 2017 11:01 am
Forum: Camera board
Topic: raspivid raw RGB data is incorrect?
Replies: 30
Views: 8320

Re: raspivid raw RGB data is incorrect?

Thank you, will test it this evening. :) If I can cut Gstreamer entirely out of the game and refactor the drone's entire video feedback subsystem to broadcast RGB scanlines in packet injection mode (ground station listening in monitor mode), I should have an rather low latency and highly robust vide...
by cpunk
Tue Aug 08, 2017 11:00 am
Forum: Beginners
Topic: Silly hardware question - sensors and relays
Replies: 4
Views: 913

Re: Silly hardware question - sensors and relays

Relays you can easily connect to GPIO pins - there are plenty of relay cards available, starting from 1 relay and ending with 10 relays, I think... Sensors... unless you mean simple on/off sensors, I would recommend looking for I2C-connectable versions, and connecting them to the I2C pins. There are...
by cpunk
Mon Aug 07, 2017 4:58 pm
Forum: Camera board
Topic: raspivid raw RGB data is incorrect?
Replies: 30
Views: 8320

Re: raspivid raw RGB data is incorrect?

Wow, nice. :) If you need testers at any point, just drop a line here - I would definitely be interested in trying (although I don't think I have ever compiled firmware for anything GPU-related - only to put the WiFi card in packet injection mode).
by cpunk
Sun Aug 06, 2017 4:16 pm
Forum: Camera board
Topic: raspivid raw RGB data is incorrect?
Replies: 30
Views: 8320

Re: raspivid raw RGB data is incorrect?

P.S. Maybe this problem of getting YUV instead of RGB is specific to low resolutions?
by cpunk
Sun Aug 06, 2017 4:14 pm
Forum: Other projects
Topic: waterthight case
Replies: 19
Views: 11737

Re: waterthight case

Or alternatively, just put a package of moisture-absorbing silica granules along with electronics into the box. Might also help, but needs regular (yearly?) replacement.
by cpunk
Sun Aug 06, 2017 3:06 pm
Forum: Camera board
Topic: raspivid raw RGB data is incorrect?
Replies: 30
Views: 8320

Re: raspivid raw RGB data is incorrect?

P.S. I also have:

Code: Select all

raspivid Camera App v1.3.12
by cpunk
Sun Aug 06, 2017 3:02 pm
Forum: Camera board
Topic: raspivid raw RGB data is incorrect?
Replies: 30
Views: 8320

Re: raspivid raw RGB data is incorrect?

Thanks for trying... it is strange to hear that somewhere, it is outputting RGB. So I tried recreating that (but could not). First I reinstalled the following packages: libraspberrypi-bin libraspberrypi0 raspi-config Output was: (Reading database ... 70121 files and directories currently installed.)...
by cpunk
Sun Aug 06, 2017 2:06 pm
Forum: Camera board
Topic: Low Framerate(6fps) While Recoding 1080P via V4L2
Replies: 6
Views: 3068

Re: Low Framerate(6fps) While Recoding 1080P via V4L2

Maybe you are accidentally forcing V4L to convert the video from one size to another (or one pixel format to another)? If that happens, it will do that using CPU resources. Meanwhile, "raspivid" lets the GPU do such things...
by cpunk
Sat Aug 05, 2017 8:12 pm
Forum: High Altitude Balloon
Topic: Radio Communications: Proper Guide for Newbies?
Replies: 7
Views: 13241

Re: Radio Communications: Proper Guide for Newbies?

Not sure if it's legal in the country you reside in (it has 33dBm of RF output), but I'm using the E31-TTL-2W from CDE for more than just hobby projects, but also industrial telemetry and a prototype environmental monitoring mesh. It's a narrow band radio modem with adjustable frequency channels. No...
by cpunk
Sat Aug 05, 2017 8:01 pm
Forum: Troubleshooting
Topic: Tele-control has delays?
Replies: 3
Views: 598

Re: Tele-control has delays?

Tried it, but no remarkable delay here. :)
by cpunk
Sat Aug 05, 2017 7:02 pm
Forum: Camera board
Topic: Kernel/scheduler affecting "raspivid" behaviour?
Replies: 2
Views: 963

Re: Kernel/scheduler affecting "raspivid" behaviour?

Thank you. :)

For me, it was a fortunate mishap, as due to swapping kernels back and forth trying to figure things out, I found and patched a juicy bug in my own video analysis code. :)
by cpunk
Sat Aug 05, 2017 6:58 pm
Forum: Troubleshooting
Topic: "Unable to determine hardware version"
Replies: 31
Views: 40630

Re: "Unable to determine hardware version"

Wow, thanks for the detailed info. :) And sorry for "barking up the wrong tree", at the time of writing I didn't figure out that there was library embedding going on, and that simply setting a system property could override it. :) :D
by cpunk
Thu Aug 03, 2017 9:04 am
Forum: Camera board
Topic: raspivid raw RGB data is incorrect?
Replies: 30
Views: 8320

Re: raspivid raw RGB data is incorrect?

Also, GRAY8 (-rf gray) is working as intended. :) However, since the source code suggests that GRAY8 is produced by actually running in I420 mode and sending the leading part of the buffer instead of the whole buffer, I guess I should not be surprised. :)
by cpunk
Thu Aug 03, 2017 8:44 am
Forum: Camera board
Topic: raspivid raw RGB data is incorrect?
Replies: 30
Views: 8320

Re: raspivid raw RGB data is incorrect?

I can additionally confirm that even if I override the choice between RGB and BGR, and tell it to always output BGR, it still gives me YUV. The nice thing is that I can decode the YUV like this: public class YuvToRGB { private static int R = 0; private static int G = 1; private static int B = 2; pub...
by cpunk
Wed Aug 02, 2017 5:21 pm
Forum: Camera board
Topic: raspivid raw RGB data is incorrect?
Replies: 30
Views: 8320

Re: raspivid raw RGB data is incorrect?

I am confident that "format->encoding" is set by "create_splitter_component(RASPIVID_STATE *state)". I think this is not a command line parsing problem.
by cpunk
Wed Aug 02, 2017 4:05 pm
Forum: Camera board
Topic: raspivid raw RGB data is incorrect?
Replies: 30
Views: 8320

Re: raspivid raw RGB data is incorrect?

I get the same output if I tell Gstreamer to decode H264 into I420. So I think it must be I420 ("8 bit Y plane followed by 8 bit 2x2 subsampled U and V planes", according to: https://www.fourcc.org/pixel-format/yuv-i420/ ). My versions over here are: # vcgencmd version Feb 20 2017 14:01:24 Copyright...
by cpunk
Wed Aug 02, 2017 3:11 pm
Forum: Camera board
Topic: raspivid raw RGB data is incorrect?
Replies: 30
Views: 8320

Re: raspivid raw RGB data is incorrect?

I have recreated it - definitely not the kind of RGB8 that Gstreamer outputs. Much more likely YUV or some similar format. I will try to search for it tomorrow, although I am very new to "raspivid" source code, having modified it only once before (so please don't count on me to solve it, I am more l...
by cpunk
Wed Aug 02, 2017 9:44 am
Forum: Camera board
Topic: "photon data transmission" from fast moving robot to 90fps Pi Camera
Replies: 4
Views: 818

Re: "photon data transmission" from fast moving robot to 90fps Pi Camera

For such a high frame rate, the pictures are remarkably light and contrastful. :) I wonder what tricks you are using to achieve that? :) Are you using very intensive lights?
by cpunk
Wed Aug 02, 2017 9:42 am
Forum: Camera board
Topic: raspivid raw RGB data is incorrect?
Replies: 30
Views: 8320

Re: raspivid raw RGB data is incorrect?

Interesting... I will try to recreate the effect on my system, since at some point, I would also be interested in shifting the work of producing RGB to hardware instead of Gstreamer (which I'm using currently).

I'll mention if I see something that draws attention.

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