I'm currently working on one of the last parts of a project and I'm at a standstill. I am needing to remove pixels from an image that are smaller than a certain aspect. For example, if an image has a square or triangle that is smaller than 35,35 pixels, I would need to remove it by changing its color.
Feel free to ask any questions. The images will be in a picturebox.
Thank you in advance,
Resentful
Does anyone have a clue on this?
I have a clue on it.
I should already have the code to do it. It might not make much sense to you and it won't be commented.
Do the shapes need to be less then 35x35 square pixels or need to be smaller than a 35x35 square box?
What do you mean by removing them by changing the color? What color?
The shapes would vary in size, but just XX by XX square pixels.
It would be turning the pixels to the color of white.
It probably won't be until tomorrow.
And i guess there is no color to search for. Just search all colors on the image and change the colors that are made of less than 35x35 pixels to white. So if you passed in a size of 35x35, all shapes that are less than 1225 pixels will be turned to white. So even if the shape was a long narrow shape that didn't fit into a 35x35 box but was made up of less then 1225 pixels would be turned to white.
It probably won't be until tomorrow.
And i guess there is no color to search for. Just search all colors on the image and change the colors that are made of less than 35x35 pixels to white. So if you passed in a size of 35x35, all shapes that are less than 1225 pixels will be turned to white. So even if the shape was a long narrow shape that didn't fit into a 35x35 box but was made up of less then 1225 pixels would be turned to white.
That's exactly what I would need. Any time you could get it would be great.
Thanks in advance,
Resentful
Done.
This is going to be no use to you. It does what you want but its confusing. I was going to comment it but would take an hour and still be confusing.
What your trying to do is based on a flood fill. This is a simple flood fill but is confusing because it doesn't deal with x,y coordinates but deals with indexes in the image bytes.
I would recommend searching Bob Powell flood fill. Its an easy flood fill that deals with get pixel and set pixel. If you get the basic flood fill working where it will fill a solid color you can pm me and i'll help you set it up so it searches all colors in the images. You should be able to do a copy and paste job to get it working.
This function's logic is identical to the get pixel and set pixel version from that site. Its where i based mine from a couple of years ago. Once the get pixel and set pixel version is complete you'll be able to compare the speed between the 2. You'll find this version is remarkably faster.
Happy to help.
Imports System.Runtime.InteropServices
Imports System.Drawing.Imaging
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
RemoveColors(PictureBox1.Image, New Size(35, 35))
PictureBox1.Refresh()
End Sub
Public Sub RemoveColors(ByVal bmp As Bitmap, ByVal sqPixels As Size)
If bmp Is Nothing Then Exit Sub
Dim BitmapData As BitmapData = bmp.LockBits(New Rectangle(0, 0, bmp.Width, bmp.Height), ImageLockMode.ReadWrite, bmp.PixelFormat)
Dim BitsPerPixel As Integer = BitmapData.Stride / bmp.Width
Dim OverStride As Integer = BitmapData.Stride - bmp.Width * BitsPerPixel
Dim BitmapPtr As IntPtr = BitmapData.Scan0
Dim Stack As New Stack
Dim CurrentShapeIndexes As New List(Of Integer)
Dim FirstIndex, CurrentIndex, Index, CheckedIndex As Integer
Dim IndexesChecked(bmp.Width * bmp.Height - 1) As Boolean
Dim BitmapBytes(BitmapData.Stride * bmp.Height - 1) As Byte
'Stores the color of the current color, a new color to fill it to, and
'the white color to change small shapes.
Dim OriginalColor(2) As Byte
Dim NewColor(2) As Byte
Dim WhiteColor() As Byte = {255, 255, 255}
Dim ColorToCopyBackTo(2) As Byte
'Used to check around all neighboring pixels of the current pixel.
Dim x() As Integer = {1, 0, -1, 0}
Dim y() As Integer = {0, 1, 0, -1}
Marshal.Copy(BitmapPtr, BitmapBytes, 0, BitmapBytes.Length)
Do While True
CurrentIndex = Array.IndexOf(IndexesChecked, False) * BitsPerPixel
FirstIndex = CurrentIndex
Stack.Push(CurrentIndex)
CurrentShapeIndexes.Add(CurrentIndex)
Array.Copy(BitmapBytes, CurrentIndex, OriginalColor, 0, 3)
NewColor = GetNewColor(OriginalColor)
Do While Stack.Count > 0
CurrentIndex = Stack.Pop
Array.Copy(NewColor, 0, BitmapBytes, CurrentIndex, 3)
For i = 0 To 3
If ((CurrentIndex) Mod BitmapData.Stride = 0 And x(i) = -1) OrElse ((CurrentIndex + BitsPerPixel + OverStride) Mod BitmapData.Stride = 0 And x(i) = 1) Then Continue For
Index = CurrentIndex + (y(i) * (BitmapData.Stride) + x(i) * BitsPerPixel)
CheckedIndex = Index / BitsPerPixel
'check top and bottom bounds
If Index < 0 OrElse Index > BitmapBytes.Length - BitsPerPixel OrElse IndexesChecked(CheckedIndex) = True Then Continue For
If BitmapBytes(Index) = OriginalColor(0) AndAlso BitmapBytes(Index + 1) = OriginalColor(1) AndAlso BitmapBytes(Index + 2) = OriginalColor(2) Then
IndexesChecked(CheckedIndex) = True
Stack.Push(Index)
CurrentShapeIndexes.Add(Index)
End If
Next
Loop
IndexesChecked(FirstIndex / BitsPerPixel) = True
If CurrentShapeIndexes.Count < (sqPixels.Width * sqPixels.Height) Then
ColorToCopyBackTo = WhiteColor
Else
ColorToCopyBackTo = OriginalColor
End If
For i = 0 To CurrentShapeIndexes.Count - 1
Array.Copy(ColorToCopyBackTo, 0, BitmapBytes, CurrentShapeIndexes(i), 3)
Next
CurrentShapeIndexes.Clear()
If Not IndexesChecked.Contains(False) Then Exit Do
Loop
Marshal.Copy(BitmapBytes, 0, BitmapPtr, BitmapBytes.Length)
bmp.UnlockBits(BitmapData)
BitmapPtr = IntPtr.Zero
BitmapBytes = Nothing
IndexesChecked = Nothing
End Sub
Private Function GetNewColor(ByVal OriginalColor As Byte()) As Byte()
Dim newColor(2) As Byte
Randomize()
newColor(0) = 255 * Rnd()
newColor(1) = 255 * Rnd()
newColor(2) = 255 * Rnd()
Return newColor
End Function
End ClassWe're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.