Openmv4 learning notes 1 --- one click download, background knowledge of image processing, lab brightness contrast

openmv Study

1、 One click download

In the toolbar , Click on Save open script to OpenMV Cam（ As main.py）, IDE Will automatically save the current file to main.py, Very convenient .

that SD How to use the card ？SD A card is also a file system , When the power is on , If you insert SD card , that SD The file system of the card will automatically replace the built-in Flash file system , Every time you power on , It will run SD In the card main.py La , Isn't that intuitive , Very convenient .SD Card maximum support 32G The capacity of .

2、 Background knowledge of image processing

The photosensitive element is composed of many photosensitive points , Such as the 640480 A little bit , Each point is a pixel , Collect and sort out the pixels of each point , It's just a picture , So the resolution of this picture is 640480：

Frame rate （FPS） Is the number of pictures processed per second , If exceeded 20 frame , The human eye can hardly distinguish carton . Of course , If used on the machine , The higher the frame rate, the better

3、LAB brightness - Contrast

Lab In the color space ,L brightness ;a A positive number of represents red , The negative end is green ;b The positive number of represents yellow , The negative end is blue . Unlike RGB and CMYK Color space ,Lab Colors are designed to approach human vision .

therefore L Component can adjust the brightness to , modify a and b The output color scale of the component to make accurate color balance .

 Be careful ： stay OpenMV In the algorithm for finding color patches , This is what is used LAB Pattern ！

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—— Star pupil Technology