Difference between revisions of "OpenCV4"
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=== Process === | === Process === | ||
==== Install OpenCV==== | ==== Install OpenCV==== | ||
| − | Follow these instruction<ref>Open CV instruction | + | Follow these instruction<ref>Open CV instruction:[https://www.pyimagesearch.com/2018/09/26/install-opencv-4-on-your-raspberry-pi/ Link]</ref> to install OpenCV onto your Raspberry Pi using the terminal. |
*Important note: don't do <code>make-j4</code>. It may freeze so it best to just do <code>make</code> or <code>make-j1</code>. | *Important note: don't do <code>make-j4</code>. It may freeze so it best to just do <code>make</code> or <code>make-j1</code>. | ||
| Line 17: | Line 17: | ||
==== Capturing image==== | ==== Capturing image==== | ||
| − | Following these step to set up your camera<ref>Setting up camera | + | Following these step to set up your camera<ref>Setting up camera:[https://www.dexterindustries.com/howto/installing-the-raspberry-pi-camera/ Link]</ref> |
*Note: Ignoring GoPiGo installation. | *Note: Ignoring GoPiGo installation. | ||
| − | Once the camera is set up, it is ready to take pictures. In order to capture image, follow these instruction <ref>Capturing Image:[https://medium.com/@petehouston/capture-images-from-raspberry-pi-camera-module-using-picamera-505e9788d609 | + | Once the camera is set up, it is ready to take pictures. In order to capture image, follow these instruction <ref>Capturing Image:[https://medium.com/@petehouston/capture-images-from-raspberry-pi-camera-module-using-picamera-505e9788d609 Link]</ref> |
{|style="margin: 0 auto;" | {|style="margin: 0 auto;" | ||
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Once you have a picture, you may want to use edge detection to detect the chessboard region of interest. | Once you have a picture, you may want to use edge detection to detect the chessboard region of interest. | ||
| − | Follow these instruction for [https://opencv-python-tutroals.readthedocs.io/en/latest/py_tutorials/py_imgproc/py_canny/py_canny.html | + | Follow these instruction for Canny edge detection<ref>Canny edge detection:[https://opencv-python-tutroals.readthedocs.io/en/latest/py_tutorials/py_imgproc/py_canny/py_canny.html Link]</ref> |
* Note: Scroll down to the Explanation. | * Note: Scroll down to the Explanation. | ||
Revision as of 01:13, 12 December 2018
Contents
Overview
This is a tutorial on how to install OpenCV4 and use camera module.
Materials/Prerequisites
- Raspberry Pi
- Raspberry Pi Camera
Process
Install OpenCV
Follow these instruction[1] to install OpenCV onto your Raspberry Pi using the terminal.
- Important note: don't do
make-j4. It may freeze so it best to just domakeormake-j1.
After you have successfully installed OpenCV, you will be able to use import cv2. If you do it on the terminal, you want to put in these code source ~/.profile and then workon cv.
Capturing image
Following these step to set up your camera[2]
- Note: Ignoring GoPiGo installation.
Once the camera is set up, it is ready to take pictures. In order to capture image, follow these instruction [3]
Note:
- Use
sleep(measured in seconds) to create a delay between the preview:time.sleep(seconds)
- Another way to enable your camera is: go to the terminal → type in
sudo raspi-config→ selectEnable Camera→ press Enter → selectFinish→ reboot and log back on to the Raspberry Pi.
Edge Detector
Once you have a picture, you may want to use edge detection to detect the chessboard region of interest.
Follow these instruction for Canny edge detection[4]
- Note: Scroll down to the Explanation.
In order to use build-in function in Open CV: remember to import cv2. In the instruction, the import cv2 as cv means that you can now type in cv instead of cv2 when using build function.
Use the following build-in code for Canny Detection:
Canny( detected_edges, detected_edges, lowThreshold, lowThreshold*ratio, kernel_size )
Ex: To load image:
- src =
cv.imread(filename, cv.IMREAD_GRAYSCALE)
Then use:
- dst =
cv.Canny(src, 50, 200, None, 3)
Hougline Transformation
Authors
- Nhut Dang
- Robert Goodloe
- Ethan Shry(TA)
Fall 2018
