Data Extraction from Image

Hello,

I'm working on a project where I need to extract data from an image and create lookup tables in Simulink. The goal is to create two types of lookup tables:

1. 2D Lookup Table:

• Input: Y-axis values, Speed Curves (6000-17000 RPM)
• Output: X-axis values
• Purpose: To determine X values based on Y values and speed curves

1. 3D Lookup Table:

• Inputs: X values, Y values, and Speed values
• Output: Power values (ranging from 0.1 to 1.2 kW, represented by blue lines in the image)

I need guidance on:

• How to extract the necessary data from the image
• How to create these lookup tables in Simulink

Any advice or resources would be greatly appreciated!

Answer 1

[Image Analyst]

I'd work on getting the formulas that generated that image instead of trying to do OCR on all the numbers in that image and somehow recreating a table or formula from them.

[Atharva]

Thank you for your repsonse. It is possible with first principles and digitizing the compressor map, but to find curve fitting regression coefficients, its kinda is stressful. So its better, as per my understanding, to use lookup tables with prelookup (optional) for faster simulations.

Edit: I was able to do it using data extraction from GitHub - automeris-io/WebPlotDigitizer: Computer vision assisted tool to extract numerical data from plot images.

Note:

• its very easy to use
• use mask pen to highlight the required curves for X-Y values
• Filter colors and adjust data points spacing for accurate detection of the image
• Export them as per need

I used 2-D lookup Table in simulnk for simulation.