Search found 64 matches

by robusto
Tue Aug 30, 2016 8:41 am
Forum: EV3 Software
Topic: Vision for Robots
Replies: 8
Views: 1191

Re: Vision for Robots

I have a NxtCam-4 I would like to sell. Good price guaranteed.
If anyone is interested please get in touch.

Cheers,

Rob
by robusto
Thu Jun 02, 2016 11:34 am
Forum: EV3 Software
Topic: EV3 Static IP
Replies: 5
Views: 1132

Re: EV3 Static IP

Thanks. I seem to have dealt with that one in the way you suggest.
by robusto
Sun May 29, 2016 10:39 am
Forum: EV3 Software
Topic: EV3 Static IP
Replies: 5
Views: 1132

Re: EV3 Static IP

I have a project that uses two ev3s and the PC. The ev3s talk to each other and to the pc over wifi. I am trying to keep the IP addresses constant so I don't have to recode them on a run. Generally this is not a problem, but sometimes it is. I've set a static ip address for my pc - 192.168.1.101. Th...
by robusto
Fri Apr 29, 2016 11:30 am
Forum: EV3 Hardware
Topic: controlling an external motor from the EV3
Replies: 3
Views: 826

Re: controlling an external motor from the EV3

Cool - works a treat.
by robusto
Thu Apr 28, 2016 12:58 pm
Forum: EV3 Hardware
Topic: controlling an external motor from the EV3
Replies: 3
Views: 826

Re: controlling an external motor from the EV3

Cheers Andy
by robusto
Thu Apr 28, 2016 4:58 am
Forum: EV3 Hardware
Topic: controlling an external motor from the EV3
Replies: 3
Views: 826

controlling an external motor from the EV3

Hi, I did search for this topic but could not find it. Apologies if it has already been discussed. I am wanting to control a small external DC motor from the EV3. Two reasons: I have run out of lego motors and they are in any case too bulky to integrate into my robot project (which is already packed...
by robusto
Mon Mar 14, 2016 12:21 pm
Forum: EV3 Software
Topic: sending a BufferedImage over a socket
Replies: 9
Views: 1420

Re: sending a BufferedImage over a socket

Hi Andy, I'm not expecting you to solve every problem with cameras etc. I wanted your opinion on what the error might mean. I understand though that messages are not always informative. I don't need to get frames as a Mat. I have another method (byte[] frame = Video.createFrame();video.grabFrame() )...
by robusto
Fri Mar 11, 2016 11:58 am
Forum: EV3 Software
Topic: sending a BufferedImage over a socket
Replies: 9
Views: 1420

Re: sending a BufferedImage over a socket

OpenCV does not like my camera.

Error is:
VIDEOIO ERROR: V4L/V4L2: VIDIOC_S_CROP
Corrupt JPEG data: 1 extraneous bytes before marker 0xd4

I am using a Logitech 270 webcam. It's a pretty standard camera.
Opencv on the eV3 should really work with it, don't you think?
by robusto
Thu Mar 10, 2016 10:28 am
Forum: EV3 Software
Topic: sending a BufferedImage over a socket
Replies: 9
Views: 1420

Re: sending a BufferedImage over a socket

btw I'm familiar with opencv to the extent that I have implemented simple object recognition with it .
There is a lot of messing around but it's reasonably straightforward. It's the comms stuff that gives me all the problems!
by robusto
Thu Mar 10, 2016 10:22 am
Forum: EV3 Software
Topic: sending a BufferedImage over a socket
Replies: 9
Views: 1420

Re: sending a BufferedImage over a socket

Ok I'll try the opncv jpeg conversion now I've got the other working. I'm a little bit wary given the problem I mentioned in a previous post with capturing the camera image as a Mat (I get this warning Corrupt JPEG data: 3 extraneous bytes before marker 0xd2. Camera is a Logitech 270 WebCam)) But I'...
by robusto
Thu Mar 10, 2016 10:15 am
Forum: EV3 Software
Topic: sending a BufferedImage over a socket
Replies: 9
Views: 1420

Re: sending a BufferedImage over a socket

Sending the number of bytes over the stream and reading it at the other end to dimension the buffer was a success.

Thanks.
by robusto
Thu Mar 10, 2016 8:42 am
Forum: EV3 Software
Topic: sending a BufferedImage over a socket
Replies: 9
Views: 1420

Re: sending a BufferedImage over a socket

Thanks Andy for the reply. I am assuming a fixed number of bytes because I know how big the image is (160x120 pixels). Can Jpeg compression result in fewer bytes? To convert a BufferedImage to jpg I am using the standard approach with ImageIO. e.g ByteArrayOutputStream baos = new ByteArrayOutputStre...
by robusto
Wed Mar 09, 2016 12:19 pm
Forum: EV3 Software
Topic: sending a BufferedImage over a socket
Replies: 9
Views: 1420

sending a BufferedImage over a socket

What is the best way to do this? I'm sending a camera image from the EV3 to the PC for display. This is easy to implement if you grab a frame from the camera and send it over a socket as a bunch of bytes. At the PC end , you do a bit of conversion (typically YUV to RGB) , build a BufferedImage and d...
by robusto
Wed Mar 09, 2016 11:59 am
Forum: EV3 Software
Topic: openCV Corrupt JPEG data
Replies: 2
Views: 1576

Re: openCV Corrupt JPEG data

Ok Thanks
by robusto
Thu Feb 25, 2016 11:41 am
Forum: EV3 Software
Topic: openCV Corrupt JPEG data
Replies: 2
Views: 1576

openCV Corrupt JPEG data

Hi, not a question about the line following program but just a quick one on openCV. I’ve been working with the library for quite a while now, beaming my video stream up to the PC over wifi and sending commands back to the EV3. So, I’m pretty chuffed that the it has now been ported to the brick. Howe...

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