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by picamuser
Tue Nov 25, 2014 11:38 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: How to do a repeated start with the raspberry pi?
Replies: 2
Views: 772

How to do a repeated start with the raspberry pi?

I am trying to use an MMA8452Q accelerator with the raspberry pi B+. I have it hooked up to 5 gpio pins on the pi, J8 pins 1/3/5/7/9. After installing some i2c libraries, the pi recognizes the device with i2cdetect, on address 0x1d. However, when I try to read from the device, I always get back a 0 ...
by picamuser
Thu Oct 16, 2014 3:51 pm
Forum: Camera board
Topic: Pixel intensity through GPU in C++
Replies: 12
Views: 2705

Re: Pixel intensity through GPU in C++

Without knowing what you will need to do for these pixels, its hard to suggest the best option. Anyways, I recommend using MMAL because it runs really fast and you can hook it up to other things. You can get the raw buffers and send them to opencv for processing, or even look at each individual pixe...
by picamuser
Mon Sep 08, 2014 3:30 pm
Forum: Camera board
Topic: Official V4L2 driver and OpenCV
Replies: 1
Views: 778

Re: Official V4L2 driver and OpenCV

I don't know how to get v4l2 to stream video into OpenCV. But I found a code example that uses MMAL to get output from the camera and port it to OpenCV for face detection. https://github.com/tasanakorn/rpi-mmal-demo
by picamuser
Mon Aug 18, 2014 7:10 pm
Forum: Camera board
Topic: Multi camera array
Replies: 2
Views: 2912

Re: Multi camera array

1. As far as I know, you can only have one camera per raspberry pi. The compute module will support two cameras. 2. To do this project you will need multiple raspberry pis, and you will need to stream video from all of them simultaneously. It might be possible by ethernet, but it might require a spe...
by picamuser
Fri Aug 15, 2014 4:32 pm
Forum: Camera board
Topic: RASPI Camera configuration with V4l2 drivers
Replies: 8
Views: 1424

Re: RASPI Camera configuration with V4l2 drivers

https://github.com/tasanakorn/rpi-mmal-demo - This contains some basic mmal preview code, look at main.c - great starting point if you want to make your own custom application. https://github.com/raspberrypi/userland/tree/master/host_applications/linux/apps/raspicam - This contains the source of ras...
by picamuser
Fri Aug 15, 2014 4:19 pm
Forum: Camera board
Topic: RASPI Camera configuration with V4l2 drivers
Replies: 8
Views: 1424

Re: RASPI Camera configuration with V4l2 drivers

It is possible to adjust the settings of your camera in C, just use mmal. There are some examples of this online.
by picamuser
Thu Aug 14, 2014 7:28 pm
Forum: Camera board
Topic: What features/issues to address?
Replies: 96
Views: 24013

Re: What features/issues to address?

6by9 How did you just modify a custom image effect in openMAX or MMAL? It would help to know which part of the source (if its open source) holds the algorithms for doing the image effects and modifying it on the GPU. Thanks for your time. Some of the improvements (especially the recent framerate imp...
by picamuser
Mon Aug 11, 2014 8:43 pm
Forum: Camera board
Topic: Creating a custom image filter in OMX/MMAL
Replies: 0
Views: 364

Creating a custom image filter in OMX/MMAL

Hello, I am currently trying to figure out a fast way to do a threshold image filter, that displays black if luminance is below a certain value, lets say 128 for 8-bit Luminance, and white otherwise. I noticed that OpenMax and MMAL had various image filtering algorithms which were quick. I would lik...
by picamuser
Fri Jul 25, 2014 8:06 pm
Forum: Camera board
Topic: Using --gl option increases latency
Replies: 3
Views: 916

Re: Using --gl option increases latency

Jamesh, Thanks for responding. Did you find out anything useful about the OpenGL latency? Also, I noticed a bug where the y texture doesn't work with maximum resolution. So raspistill -t 300000 --preview '0, 0, 2592, 1944' --gl -gs yuv --glwin '0, 0, 1920, 1080' produces garbage output. Is there any...
by picamuser
Mon Jul 21, 2014 9:32 pm
Forum: Camera board
Topic: Using --gl option increases latency
Replies: 3
Views: 916

Using --gl option increases latency

I am currently trying to use raspicam for video. It seems to preform very well, running 2592x1944 resolution at 15 fps. However, for some reason, using the --gl command seems to increase latency in the system. For example, running the command: raspistill -t 300000 --preview '0, 0, 2592, 1944' --glwi...

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