Compare two colors. Average color of an image. Code proposals

[Juan_Antonio]

Hello friends,

in this topic I wrote about the color number:

Color number in Make color and Split color

Yellow color is: R = 255 G = 255 B = 0 opacity = 255 What color number is yellow using the make color block? N = B + (G + (R + (256 x opacity)) x 256 ) x 256 N = 0 + (255 + (255 + (256 x 255)) x 256 ) x 256 = 4294967040 With split color what list do we get with yellow color? [255, 255, 0, 255] What number is the yellow color? 4294967040 - 4294967296 = -256 [colores_RVA] colores_RVA.aia (2.6 KB) Here tutorials in Spanish: http://kio4.com/appinventor/20D_separar_rva.htm http:/…

Now I have written a tutorial on a Spanish web page with codes to compare colors, but in this topic I prefer to propose that users create the codes. If you need the codes, you can request them by message.

Here .apk files:
http://kio4.com/appinventor/apk_archivos.htm#78

[Juan_Antonio]

1.- Vector color 3D.

• Using three Sliders create a color and finds the modulus and the alpha, beta and gamma angles of an RGB color.
• Calculate the maximum value when M (255,255,255)

• Check images.

[Juan_Antonio]

2.- Compare color RGB. Method difference between RGB vectors.

Read this:

• How to compare two colors for similarity/difference (Stackoverflow)

• Color difference (Wikipedia)

• Calculate the distance and percent between the vectors M (R1, G1, B1) and N (R2, G2, B2).

Percent : d / sqrt((255)^2+(255)^2+(255)^2) = d / 4,417

[Juan_Antonio]

3.- Compare two colors using the following algorithm.

from: How to compare two colors for similarity/difference (Stackoverflow)

[Juan_Antonio]

4.- Using three Sliders create a color and compare it to the PH color scale. (use the method from the previous exercise.)

Search images PH color scale.

[Juan_Antonio]

5.- Get average color of an image.

Read this:
How can I get the average colour of an image (Stackoverflow)

• We have a jpg image, get average color of that image by two methods.
  a) Using a Canvas and the TouckDown block, tap on the image several times and get its color R, G and B, average.
  b) Using a loop for each ... from, get 200 random x, y points and calculate their average color.

[denlex]

hay can you make a complete picture of the blocks for me

[Juan_Antonio]

@denlex

If you need the codes, you can request them by message.

[Juan_Antonio]

6.- Pixelates an image with dots.

• Divide an image into rectangles. Get the color of 4 random points in each rectangle.
• Find the average color of those points. Draw a point corresponding to that rectangle on another Canvas.
  
  
  
  
  

Here .apk file.