basic image processing using OpenCV library for Python

image_processing.md

Algo

Converting multiple BMPs to an AVI without compression

You can use the huffyuv encoder to create a lossless output:

ffmpeg -i img%d.jpg -vcodec huffyuv output.avi

or rawvideo:

ffmpeg -i img%d.jpg -vcodec rawvideo output.avi

By default this will assume your input frame rate is 25, so you can add an option to change it:

ffmpeg -r 30 -i img%d.jpg -vcodec huffyuv output.avi

By default the output will inherit the input frame rate. You can apply the same option to the output. By changing the frame rates you can achieve a certain duration. For example, if I have 900 images and want the output duration to be 60 seconds with an output frame rate of 30, then 900/60=15.

ffmpeg -r 15 -i img%d.jpg -r 30 -vcodec huffyuv output.avi

Note that your images must be named in a sequence starting with 1, and although some encoders are lossless there can be some loss due to colorspace conversion. See FFmpeg FAQ: How do I encode single pictures into movies? (http://ffmpeg.org/faq.html#SEC14) for more info.

credit : https://ubuntuforums.org/archive/index.php/t-1815998.html

update frame in matplotlib with live camera preview

credit: https://stackoverflow.com/questions/44598124/update-frame-in-matplotlib-with-live-camera-preview

Temporal median image of multiple images

credit: https://stackoverflow.com/questions/28682985/temporal-median-image-of-multiple-images

Most efficient way to map function over numpy array

credit: https://stackoverflow.com/questions/35215161/most-efficient-way-to-map-function-over-numpy-array

connected component labeling in python

credit: https://stackoverflow.com/questions/46441893/connected-component-labeling-in-python

How to remove small connected objects using OpenCV

credit: https://stackoverflow.com/questions/42798659/how-to-remove-small-connected-objects-using-opencv

Morphological Transformations

https://docs.opencv.org/3.0-beta/doc/py_tutorials/py_imgproc/py_morphological_ops/py_morphological_ops.html

Structural Analysis and Shape Descriptors

https://docs.opencv.org/3.0-beta/modules/imgproc/doc/structural_analysis_and_shape_descriptors.html#connectedcomponents

Linear Interpolation using numpy.interp

https://stackoverflow.com/questions/13166914/linear-interpolation-using-numpy-interp

Apply a function repeatedly over multiple axes

https://docs.scipy.org/doc/numpy-1.13.0/reference/generated/numpy.apply_along_axis.html

How to create a 2D “rect” array (square block of 1's, else 0's) in numpy?

https://stackoverflow.com/questions/10159178/how-to-create-a-2d-rect-array-square-block-of-1s-else-0s-in-numpy

How to print the full NumPy array?

https://stackoverflow.com/questions/1987694/how-to-print-the-full-numpy-array

Creating a GIF animation from PNG files

https://unix.stackexchange.com/questions/24014/creating-a-gif-animation-from-png-files

Fuzzy Control Systems: The Tipping Problem

http://pythonhosted.org/scikit-fuzzy/auto_examples/plot_tipping_problem_newapi.html

Online curve fitting

https://mycurvefit.com/

Communication

Inter-process Communication

https://en.wikipedia.org/wiki/Inter-process_communication