Unity - Pick color in the screen point (x, y)

CheckPixelColor.cs

using System.Collections;
using UnityEngine;
using UnityEngine.EventSystems;

public class CheckPixelColor : MonoBehaviour {
    private void Update() {
        if (Input.GetMouseButtonDown(0)) {
            if (EventSystem.current.IsPointerOverGameObject(-1) || EventSystem.current.IsPointerOverGameObject(0) ||
                EventSystem.current.IsPointerOverGameObject(1)) {
                return;
            }

            Vector3 pos = transform.position;
            StartCoroutine(CheckColor((int) pos.x, (int) pos.y));
        }
    }

    private IEnumerator CheckColor(int x, int y) {
        Texture2D tex = new Texture2D(1, 1, TextureFormat.RGB24, false);
        yield return new WaitForEndOfFrame();
        tex.ReadPixels(new Rect(x, y, Screen.width, Screen.height), 0, 0, false);
        tex.Apply(false);

        RenderTexture currentRT = RenderTexture.active;

        RenderTexture renderTexture = new RenderTexture(1, 1, 32);
        Graphics.Blit(tex, renderTexture);

        RenderTexture.active = renderTexture;

        Color pixel = tex.GetPixel(x, y);

        if (pixel.g == 0 && pixel.b == 0) {
            // Black
        } else {
            // Some other color
        }

        RenderTexture.active = currentRT;
    }
}

In 3D environments, I found this working.

private IEnumerator CheckColor() {
    Rect viewRect = Camera.main.pixelRect;
    Texture2D tex = new Texture2D((int) viewRect.width, (int) viewRect.height, TextureFormat.RGB24, false);

    yield return new WaitForEndOfFrame();

    tex.ReadPixels(viewRect, 0, 0, false);
    tex.Apply(false);

    // transform.position -> position you want to get the color
    Vector3 pos = Camera.main.WorldToScreenPoint(transform.position);
    Color pixel = tex.GetPixel((int) pos.x, (int) pos.y);
    if (pixel.g == 0 && pixel.b == 0) {
        // Black
    } else {
        // Some other color
    }
}