Android Question [B4X] [Solved] Get a list of colours in a bitmap

Sub GetColours (bmp As B4XBitmap) As List
   
    Dim l As List
    l.Initialize
   
    Dim x As Int
   
    Dim bc As BitmapCreator = CreateBC(bmp)
   
    For x = 0 To bc.mWidth - 1                'Create a list of all the colors in the bitmap
        For y = 0 To bc.mHeight - 1
            l.add (Bit.ToHexString (bc.GetColor(x,y)))
        Next
    Next
   
    l = RemoveDuplicates (l)

    Return l
   
End Sub

Sub RemoveDuplicates(pList As List) As List            'Get rid of the duplicates
    If pList = Null Or Not(pList.IsInitialized) Then Return pList
 
    Dim lstNew As List : lstNew.Initialize
    Dim objItem As Object
   
    For i = 0 To pList.Size - 1
        objItem = pList.Get(i)
        If lstNew.IndexOf(objItem) = - 1 Then
            lstNew.Add(objItem)
        End If
    Next
 
    Return lstNew
End Sub

Sub Class_Globals
    Private Root As B4XView
    Private xui As XUI
    Private ImageView1 As B4XView
    Private ImageView2 As B4XView
  

End Sub

Public Sub Initialize
    B4XPages.GetManager.LogEvents = True
End Sub

'This event will be called once, before the page becomes visible.
Private Sub B4XPage_Created (Root1 As B4XView)
    Root = Root1
    Root.LoadLayout("MainPage")
End Sub

'You can see the list of page related events in the B4XPagesManager object. The event name is B4XPage.

Private Sub Button1_Click
    Dim bmp As B4XBitmap
  
    Dim colourlist As Map
    colourlist.Initialize
  
    bmp = ImageView1.GetBitmap
    bmp = bmp.Resize (320, 240, True)
  
    bmp = BinColors (bmp)                'Change bitmap to 16 colours
  
    colourlist = GetColours (bmp)

    bmp = bmp.Resize (ImageView2.Width, ImageView2.Height,True)        'resize and display image
    ImageView2.SetBitmap (bmp)
  
    Log (colourlist)        'Always the same no matter what bitmap I use
  
  
End Sub



Private Sub CreateBC(bmp As B4XBitmap) As BitmapCreator
    Dim bc As BitmapCreator
    bc.Initialize(bmp.Width / bmp.Scale, bmp.Height / bmp.Scale)
    bc.CopyPixelsFromBitmap(bmp)
    Return bc
End Sub

Public Sub BinColors (bmp As B4XBitmap) As B4XBitmap
  
    Dim bc As BitmapCreator = CreateBC(bmp)
    Dim argb As ARGBColor
  
  
    For x = 0 To bc.mWidth - 1
        For y = 0 To bc.mHeight - 1
            bc.GetARGB(x, y, argb)
            argb.r = argb.r - (argb.r Mod 128)
            argb.g = argb.g - (argb.g Mod 128)
            argb.b = argb.b - (argb.b Mod 128)
            bc.SetARGB(x, y, argb)
        Next
    Next
    Return bc.Bitmap
  
End Sub

Sub GetColours (bmp As B4XBitmap) As Map
  
    Dim m As Map
    m.Initialize
  
    Dim x As Int
  
    Dim bc As BitmapCreator = CreateBC(bmp)
  
    For x = 0 To bc.mWidth - 1                'Create a list of all the colors in the bitmap
        For y = 0 To bc.mHeight - 1
            m.Put (Bit.ToHexString (bc.GetColor(x,y)), Bit.ToHexString (bc.GetColor(x,y)))
        Next
    Next
  
    Return m
  
End Sub

    For x = 0 To bc.mWidth - 1
        For y = 0 To bc.mHeight - 1
            bc.GetARGB(x, y, argb)
            argb.r = argb.r - (argb.r Mod 128)      '<-- results in 0 or 128
            argb.g = argb.g - (argb.g Mod 64)      '<--- will result in 0,64,128 or 192
            argb.b = argb.b - (argb.b Mod 128)    '<-- results in 0 or 128
            bc.SetARGB(x, y, argb)
        Next
    Next