Image Processing

Start command: npm start

Server diagram

Google Drawing

Web interface

Colorspace buttons

Need buttons. Only one able to be selected at a time.

Labels:

• BGR (default)
• HSV
• HLS
• Lab
• Luv
• YCrCb
• XYZ
• Grayscale

Sliders

Need six sliders (eventually only three):

Labels:

• Channel 1 Min
• Channel 2 Max
• Channel 3 Min
• Channel 4 Max
• Channel 5 Min
• Channel 6 Max

Current implementation assumes the slider ranges are all 0 to 100. We need to change this before deployment. The allowable slider range should depend on the colorspace selected:

• BGR: 0, 255, 0, 255, 0, 255
• HSV: 0, 179, 0, 255, 0, 255
• HLS: same as HSV
• Lab: 0, 255, 1, 255, 1, 255
• Luv: same as BGR
• YCrCb: same as BGR
• XYZ: same as BGR
• Grayscale: same as BGR

All sliders should have a step size of one.

Nice-to-have: Grayscale will only use the first two sliders (it's a one-channel image). If we could gray-out the other four sliders and not allow the user to interact with them, or otherwise find a way to notify them that the other four sliders will not affect the image.

Preferrably when a user switches the colorspace, we would try to move the sliders to a similar position in the new colorspace. I.e., 255 from the first slider in the BGR colorspace should be 179 in the HSV colorspace.

Python script trigger

At first we can simply create a button, and when the user presses that button, it will get the current slider values and run the script for that.

Eventually it would be nice to automagically trigger once the user changes the slider position (waiting until mouse release).

Image view window

Upon upload, the normal full-color image should be displayed. Then once the python script is triggered, we need to load the new output image into the image window.

I/O

Input

To run the python script, we need to send a JSON dictionary into the python script cspaceIO.py. The JSON dictionary needs to include the fields paths, cspaceLabel, and sliderPos. The field paths is itself a dictionary with the fields srcPath, dstPath, and dstPath2, which are the paths to the source and output images. cspaceLabel should be a string, with the same values allowed as the colorspace buttons, and sliderPos needs to be a list of the six slider positions (should be six integers).

Note: Output paths should always be specified as .png files.

Filetype support

Note that .gif files are not supported by OpenCV. List of supported filetypes (from OpenCV docs):

Windows bitmaps - *.bmp, *.dib
JPEG files - *.jpeg, *.jpg, *.jpe
JPEG 2000 files - *.jp2
Portable Network Graphics - *.png
WebP - *.webp
Portable image format - *.pbm, *.pgm, *.ppm
Sun rasters - *.sr, *.ras
TIFF files - *.tiff, *.tif

Eventually may use another library to open .gif files since they are so prevalent (but not animated). Need to test all these filetypes to ensure the Linux distro we're using has all the proper libraries for these image types.

Output

The python script cspaceIO.py does not output anything, only writes the image to the specified output path.