增加图像中特定颜色的亮度？
Increase brightness of specific color in image?
有这样一张图片（原始大小增加了 100%）：
在 C# 或 Vb.Net 下，我想知道是否可以使用颜色矩阵或其他解决方法将 brightness/luminosity 仅增加到该图像的 white/greyed 颜色，同时保持黑色背景颜色不变？
换句话说，我想让白色十字更亮（只有十字，white/grey 像素）。
这是我期望达到的亮度结果：
两张图片均来自第三方应用程序，我显示的第一张图片来自未聚焦的关闭按钮，第二张图片是同一按钮聚焦的图片，图片的黑色部分是该按钮的背景第 3 方应用
问题是，出于个人原因，在我自己的应用程序中，我将该图像用作关闭按钮和相同的背景颜色，然后我只是想通过为"X"在那张图片中，我需要对其他图片做同样的事情。
我的图像处理知识很差，我一直在寻找下面这样的方法，但我无法得到预期的结果，因为整个图像的亮度增加了：
Adjust brightness contrast and gamma of an image
更新
我正在尝试使用@Paul Ishak 方法。
我在图片框上设置了图像，想法是当用户悬停控件时增加亮度，并在鼠标离开时重置图像，
我第二次尝试调整亮度时，它在这一行抛出 ArgumentException：
bm = New Bitmap(image.Width, image.Height, System.Drawing.Imaging.PixelFormat.Format32bppArgb)
带有此消息：
A first chance exception of type 'System.ArgumentException' occurred
in System.Drawing.dll
这是我正在使用的代码，有什么问题吗？：
Private minimizeBitmap As Bitmap
Private Sub PictureBox_MinimizeButton_MouseEnter(ByVal sender As Object, ByVal e As EventArgs) _
Handles PictureBox_MinimizeButton.MouseEnter
Dim pcb As PictureBox = DirectCast(sender, PictureBox)
If Me.minimizeBitmap Is Nothing Then
Me.minimizeBitmap = New Bitmap(pcb.ClientRectangle.Width, pcb.ClientRectangle.Height)
pcb.DrawToBitmap(Me.minimizeBitmap, pcb.ClientRectangle)
End If
pcb.BackgroundImage = BrightenPixels(Me.minimizeBitmap, threshold:=33, modTimes:=5D)
End Sub
Private Sub PictureBox_MinimizeButton_MouseLeave(ByVal sender As Object, ByVal e As EventArgs) _
Handles PictureBox_MinimizeButton.MouseLeave
If Me.minimizeBitmap IsNot Nothing Then
Me.minimizeBitmap.Dispose()
End If
DirectCast(sender, PictureBox).BackgroundImage = Nothing
End Sub
Public Function BrightenPixels(ByVal image As Bitmap, threshold As Decimal, modTimes As Decimal) As Bitmap
Dim bmp As Bitmap
modTimes = Math.Abs(modTimes)
If image Is Nothing Then
Throw New ArgumentNullException(paramname:="image")
End If
Try
bmp = New Bitmap(image.Width, image.Height, System.Drawing.Imaging.PixelFormat.Format32bppArgb)
Catch ex As Exception
MsgBox(ex.GetType.Name)
MsgBox(ex.Message)
End Try
Dim g As Graphics = Graphics.FromImage(bmp)
g.DrawImage(image, New Point(0, 0))
Dim rect As New Rectangle(New Point(0, 0), bmp.Size)
Dim bitmapData As System.Drawing.Imaging.BitmapData = bmp.LockBits(rect, Imaging.ImageLockMode.ReadWrite, System.Drawing.Imaging.PixelFormat.Format32bppArgb)
Dim ptr As IntPtr = bitmapData.Scan0
Dim byteCount As Integer = bitmapData.Stride * bitmapData.Height
Dim argb(byteCount - 1) As Byte
Marshal.Copy(ptr, argb, 0, byteCount)
For i As Integer = 0 To byteCount - 1 Step 4
Dim red As Decimal = argb(i + 2)
Dim green As Decimal = argb(i + 1)
Dim blue As Decimal = argb(i)
Dim percentR As Decimal = (red / 255) * 100
Dim percentG As Decimal = (green / 255) * 100
Dim percentB As Decimal = (blue / 255) * 100
Dim aboveThresholdCount As Integer = 0
If percentR > threshold Then aboveThresholdCount += 1
If percentG > threshold Then aboveThresholdCount += 1
If percentB > threshold Then aboveThresholdCount += 1
' Label3.Text = aboveThresholdCount.ToString
If aboveThresholdCount = 3 Then
red = red * modTimes
green = green * modTimes
blue = blue * modTimes
If red > 255 Then red = 255
If green > 255 Then green = 255
If blue > 255 Then blue = 255
End If
argb(i + 2) = CByte(Math.Round(red, 0))
argb(i + 1) = CByte(Math.Round(green, 0))
argb(i) = CByte(Math.Round(blue, 0))
Next
Marshal.Copy(argb, 0, ptr, byteCount)
bmp.UnlockBits(bitmapData)
Return bmp
End Function
此示例将显示在鼠标进入和离开时修改的图像 'X'。
（示例 2 会将图像缩小 50%）
请尝试为此示例创建一个新的 Visual Basic Winforms 应用程序。请在修改之前按原样尝试此示例！
1.) 创建新项目
2.) 用这段代码替换Form1的所有代码（只修改图片路径，没有别的）
3.) 点击运行.
4.) 将鼠标移入和移出 "X"
示例 1：
Option Strict On
Option Explicit On
Option Infer Off
Public Class Form1
Private originalPic As Bitmap = Nothing
Friend WithEvents PictureBox1 As New PictureBox With {.Parent = Me, .Location = New Point(10, 10)}
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
'Only modify this line to the location of your "x" image'
Dim exPath As String = System.IO.Path.Combine(My.Computer.FileSystem.SpecialDirectories.Desktop, "picexample.jpg")
AddHandler PictureBox1.MouseMove, AddressOf PictureBox1_MouseMove
If System.IO.File.Exists(exPath) Then
originalPic = CType(Image.FromFile(exPath), Bitmap)
PictureBox1.Size = originalPic.Size
PictureBox1.Image = originalPic
Else
Application.Exit()
End If
End Sub
Public Function BrightenPixels(ByVal Image As Bitmap, threshold As Decimal, modTimes As Decimal) As Bitmap
modTimes = Math.Abs(modTimes)
If Image Is Nothing Then Return Nothing
Dim bm As New Bitmap(Image.Width, Image.Height, System.Drawing.Imaging.PixelFormat.Format32bppArgb)
Dim g As Graphics = Graphics.FromImage(bm)
g.DrawImage(Image, New Point(0, 0))
Dim rect As New Rectangle(New Point(0, 0), bm.Size)
Dim bitmapData As System.Drawing.Imaging.BitmapData = bm.LockBits(rect, Imaging.ImageLockMode.ReadWrite, System.Drawing.Imaging.PixelFormat.Format32bppArgb)
Dim ptr As IntPtr = bitmapData.Scan0
Dim byteCount As Integer = bitmapData.Stride * bitmapData.Height
Dim argb(byteCount - 1) As Byte
System.Runtime.InteropServices.Marshal.Copy(ptr, argb, 0, byteCount)
For i As Integer = 0 To byteCount - 1 Step 4
Dim alpha As Decimal = argb(i + 3)
Dim red As Decimal = argb(i + 2)
Dim green As Decimal = argb(i + 1)
Dim blue As Decimal = argb(i)
Dim percentR As Decimal = (red / 255) * 100
Dim percentG As Decimal = (green / 255) * 100
Dim percentB As Decimal = (blue / 255) * 100
Dim aboveThresholdCount As Integer = 0
If percentR > threshold Then aboveThresholdCount += 1
If percentG > threshold Then aboveThresholdCount += 1
If percentB > threshold Then aboveThresholdCount += 1
If aboveThresholdCount = 3 Then
red = red * modTimes
green = green * modTimes
blue = blue * modTimes
If red > 255 Then red = 255
If green > 255 Then green = 255
If blue > 255 Then blue = 255
End If
argb(i + 2) = CByte(Math.Round(red, 0))
argb(i + 1) = CByte(Math.Round(green, 0))
argb(i) = CByte(Math.Round(blue, 0))
Next
System.Runtime.InteropServices.Marshal.Copy(argb, 0, ptr, byteCount)
bm.UnlockBits(bitmapData)
Return bm
End Function
Private Sub PictureBox1_MouseMove(sender As Object, e As MouseEventArgs) Handles PictureBox1.MouseMove
Dim intersectionRect As New Rectangle(13, 18, 22, 21)
Dim mouseRect As New Rectangle(PictureBox1.PointToClient(MousePosition), New Size(1, 1))
Me.Text = mouseRect.ToString
If intersectionRect.IntersectsWith(mouseRect) Then
Dim tmp As Bitmap = BrightenPixels(originalPic, 33, 1.5D)
'---------------------Delete this section of code(inbetween lines) to remove circular highlight----------'
Using g As Graphics = Graphics.FromImage(tmp)
Using gp As New System.Drawing.Drawing2D.GraphicsPath
gp.AddRectangle(intersectionRect)
Using pgp As New System.Drawing.Drawing2D.PathGradientBrush(gp)
Dim center As New PointF(intersectionRect.Left + (intersectionRect.Width \ 2), intersectionRect.Top + (intersectionRect.Height \ 2))
pgp.CenterPoint = center
pgp.CenterColor = Color.FromArgb(64, Color.White)
pgp.SurroundColors = {Color.FromArgb(0, Color.White), Color.FromArgb(0, Color.White)}
g.FillPath(pgp, gp)
End Using
End Using
End Using
'-----------------------------------------------------------------------------------------------------------'
PictureBox1.Image = tmp
Else
PictureBox1.Image = originalPic
End If
End Sub
End Class
示例 2（图像 sh运行ken by 50%）：
Option Strict On
Option Explicit On
Option Infer Off
Public Class Form1
Private originalPic As Bitmap = Nothing
Private intersectionPic As Bitmap = Nothing
Private intersectionRect As New Rectangle(6, 9, 11, 10)
Friend WithEvents PictureBox1 As New PictureBox With {.Parent = Me, .Location = New Point(10, 10)}
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
'Only modify this line to the location of your "x" image'
Dim exPath As String = System.IO.Path.Combine(My.Computer.FileSystem.SpecialDirectories.Desktop, "picexample.jpg")
AddHandler PictureBox1.MouseMove, AddressOf PictureBox1_MouseMove
If System.IO.File.Exists(exPath) Then
Dim img As Bitmap = CType(Image.FromFile(exPath), Bitmap)
Dim bm As New Bitmap(img.Width \ 2, img.Height \ 2, System.Drawing.Imaging.PixelFormat.Format32bppArgb)
Dim g1 As Graphics = Graphics.FromImage(bm)
Dim cRect As New Rectangle(New Point(0, 0), bm.Size)
g1.DrawImage(CType(Image.FromFile(exPath), Bitmap), cRect)
originalPic = bm
Dim tmp As Bitmap = BrightenPixels(originalPic, 33, 1.5D)
'---------------------Delete this section of code(inbetween lines) to remove circular highlight----------'
Using g2 As Graphics = Graphics.FromImage(tmp)
Using gp As New System.Drawing.Drawing2D.GraphicsPath
gp.AddRectangle(intersectionRect)
Using pgp As New System.Drawing.Drawing2D.PathGradientBrush(gp)
Dim center As New PointF(intersectionRect.Left + (intersectionRect.Width \ 2), intersectionRect.Top + (intersectionRect.Height \ 2))
pgp.CenterPoint = center
pgp.CenterColor = Color.FromArgb(128, Color.White)
pgp.SurroundColors = {Color.FromArgb(0, Color.White), Color.FromArgb(0, Color.White)}
g2.FillPath(pgp, gp)
End Using
End Using
End Using
'-----------------------------------------------------------------------------------------------------------'
intersectionPic = tmp
PictureBox1.Size = originalPic.Size
PictureBox1.Image = originalPic
Else
Application.Exit()
End If
End Sub
Public Function BrightenPixels(ByVal Image As Bitmap, threshold As Decimal, modTimes As Decimal) As Bitmap
modTimes = Math.Abs(modTimes)
If Image Is Nothing Then Return Nothing
Dim bm As New Bitmap(Image.Width, Image.Height, System.Drawing.Imaging.PixelFormat.Format32bppArgb)
Dim g As Graphics = Graphics.FromImage(bm)
g.DrawImage(Image, New Point(0, 0))
Dim rect As New Rectangle(New Point(0, 0), bm.Size)
Dim bitmapData As System.Drawing.Imaging.BitmapData = bm.LockBits(rect, Imaging.ImageLockMode.ReadWrite, System.Drawing.Imaging.PixelFormat.Format32bppArgb)
Dim ptr As IntPtr = bitmapData.Scan0
Dim byteCount As Integer = bitmapData.Stride * bitmapData.Height
Dim argb(byteCount - 1) As Byte
System.Runtime.InteropServices.Marshal.Copy(ptr, argb, 0, byteCount)
For i As Integer = 0 To byteCount - 1 Step 4
Dim alpha As Decimal = argb(i + 3)
Dim red As Decimal = argb(i + 2)
Dim green As Decimal = argb(i + 1)
Dim blue As Decimal = argb(i)
Dim percentR As Decimal = (red / 255) * 100
Dim percentG As Decimal = (green / 255) * 100
Dim percentB As Decimal = (blue / 255) * 100
Dim aboveThresholdCount As Integer = 0
If percentR > threshold Then aboveThresholdCount += 1
If percentG > threshold Then aboveThresholdCount += 1
If percentB > threshold Then aboveThresholdCount += 1
If aboveThresholdCount = 3 Then
red = red * modTimes
green = green * modTimes
blue = blue * modTimes
If red > 255 Then red = 255
If green > 255 Then green = 255
If blue > 255 Then blue = 255
End If
argb(i + 2) = CByte(Math.Round(red, 0))
argb(i + 1) = CByte(Math.Round(green, 0))
argb(i) = CByte(Math.Round(blue, 0))
Next
System.Runtime.InteropServices.Marshal.Copy(argb, 0, ptr, byteCount)
bm.UnlockBits(bitmapData)
Return bm
End Function
Private Sub PictureBox1_MouseMove(sender As Object, e As MouseEventArgs) Handles PictureBox1.MouseMove
Dim mouseRect As New Rectangle(PictureBox1.PointToClient(MousePosition), New Size(1, 1))
Me.Text = mouseRect.ToString
If intersectionRect.IntersectsWith(mouseRect) Then
PictureBox1.Image = intersectionPic
Else
PictureBox1.Image = originalPic
End If
End Sub
End Class
有这样一张图片（原始大小增加了 100%）：
在 C# 或 Vb.Net 下，我想知道是否可以使用颜色矩阵或其他解决方法将 brightness/luminosity 仅增加到该图像的 white/greyed 颜色，同时保持黑色背景颜色不变？
换句话说，我想让白色十字更亮（只有十字，white/grey 像素）。
这是我期望达到的亮度结果：
两张图片均来自第三方应用程序，我显示的第一张图片来自未聚焦的关闭按钮，第二张图片是同一按钮聚焦的图片，图片的黑色部分是该按钮的背景第 3 方应用
问题是，出于个人原因，在我自己的应用程序中，我将该图像用作关闭按钮和相同的背景颜色，然后我只是想通过为"X"在那张图片中，我需要对其他图片做同样的事情。
我的图像处理知识很差，我一直在寻找下面这样的方法，但我无法得到预期的结果，因为整个图像的亮度增加了：
Adjust brightness contrast and gamma of an image
更新
我正在尝试使用@Paul Ishak 方法。
我在图片框上设置了图像，想法是当用户悬停控件时增加亮度，并在鼠标离开时重置图像，
我第二次尝试调整亮度时，它在这一行抛出 ArgumentException：
bm = New Bitmap(image.Width, image.Height, System.Drawing.Imaging.PixelFormat.Format32bppArgb)
带有此消息：
A first chance exception of type 'System.ArgumentException' occurred in System.Drawing.dll
这是我正在使用的代码，有什么问题吗？：
Private minimizeBitmap As Bitmap
Private Sub PictureBox_MinimizeButton_MouseEnter(ByVal sender As Object, ByVal e As EventArgs) _
Handles PictureBox_MinimizeButton.MouseEnter
Dim pcb As PictureBox = DirectCast(sender, PictureBox)
If Me.minimizeBitmap Is Nothing Then
Me.minimizeBitmap = New Bitmap(pcb.ClientRectangle.Width, pcb.ClientRectangle.Height)
pcb.DrawToBitmap(Me.minimizeBitmap, pcb.ClientRectangle)
End If
pcb.BackgroundImage = BrightenPixels(Me.minimizeBitmap, threshold:=33, modTimes:=5D)
End Sub
Private Sub PictureBox_MinimizeButton_MouseLeave(ByVal sender As Object, ByVal e As EventArgs) _
Handles PictureBox_MinimizeButton.MouseLeave
If Me.minimizeBitmap IsNot Nothing Then
Me.minimizeBitmap.Dispose()
End If
DirectCast(sender, PictureBox).BackgroundImage = Nothing
End Sub
Public Function BrightenPixels(ByVal image As Bitmap, threshold As Decimal, modTimes As Decimal) As Bitmap
Dim bmp As Bitmap
modTimes = Math.Abs(modTimes)
If image Is Nothing Then
Throw New ArgumentNullException(paramname:="image")
End If
Try
bmp = New Bitmap(image.Width, image.Height, System.Drawing.Imaging.PixelFormat.Format32bppArgb)
Catch ex As Exception
MsgBox(ex.GetType.Name)
MsgBox(ex.Message)
End Try
Dim g As Graphics = Graphics.FromImage(bmp)
g.DrawImage(image, New Point(0, 0))
Dim rect As New Rectangle(New Point(0, 0), bmp.Size)
Dim bitmapData As System.Drawing.Imaging.BitmapData = bmp.LockBits(rect, Imaging.ImageLockMode.ReadWrite, System.Drawing.Imaging.PixelFormat.Format32bppArgb)
Dim ptr As IntPtr = bitmapData.Scan0
Dim byteCount As Integer = bitmapData.Stride * bitmapData.Height
Dim argb(byteCount - 1) As Byte
Marshal.Copy(ptr, argb, 0, byteCount)
For i As Integer = 0 To byteCount - 1 Step 4
Dim red As Decimal = argb(i + 2)
Dim green As Decimal = argb(i + 1)
Dim blue As Decimal = argb(i)
Dim percentR As Decimal = (red / 255) * 100
Dim percentG As Decimal = (green / 255) * 100
Dim percentB As Decimal = (blue / 255) * 100
Dim aboveThresholdCount As Integer = 0
If percentR > threshold Then aboveThresholdCount += 1
If percentG > threshold Then aboveThresholdCount += 1
If percentB > threshold Then aboveThresholdCount += 1
' Label3.Text = aboveThresholdCount.ToString
If aboveThresholdCount = 3 Then
red = red * modTimes
green = green * modTimes
blue = blue * modTimes
If red > 255 Then red = 255
If green > 255 Then green = 255
If blue > 255 Then blue = 255
End If
argb(i + 2) = CByte(Math.Round(red, 0))
argb(i + 1) = CByte(Math.Round(green, 0))
argb(i) = CByte(Math.Round(blue, 0))
Next
Marshal.Copy(argb, 0, ptr, byteCount)
bmp.UnlockBits(bitmapData)
Return bmp
End Function
此示例将显示在鼠标进入和离开时修改的图像 'X'。
（示例 2 会将图像缩小 50%）
请尝试为此示例创建一个新的 Visual Basic Winforms 应用程序。请在修改之前按原样尝试此示例！
1.) 创建新项目
2.) 用这段代码替换Form1的所有代码（只修改图片路径，没有别的）
3.) 点击运行.
4.) 将鼠标移入和移出 "X"
示例 1：
Option Strict On
Option Explicit On
Option Infer Off
Public Class Form1
Private originalPic As Bitmap = Nothing
Friend WithEvents PictureBox1 As New PictureBox With {.Parent = Me, .Location = New Point(10, 10)}
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
'Only modify this line to the location of your "x" image'
Dim exPath As String = System.IO.Path.Combine(My.Computer.FileSystem.SpecialDirectories.Desktop, "picexample.jpg")
AddHandler PictureBox1.MouseMove, AddressOf PictureBox1_MouseMove
If System.IO.File.Exists(exPath) Then
originalPic = CType(Image.FromFile(exPath), Bitmap)
PictureBox1.Size = originalPic.Size
PictureBox1.Image = originalPic
Else
Application.Exit()
End If
End Sub
Public Function BrightenPixels(ByVal Image As Bitmap, threshold As Decimal, modTimes As Decimal) As Bitmap
modTimes = Math.Abs(modTimes)
If Image Is Nothing Then Return Nothing
Dim bm As New Bitmap(Image.Width, Image.Height, System.Drawing.Imaging.PixelFormat.Format32bppArgb)
Dim g As Graphics = Graphics.FromImage(bm)
g.DrawImage(Image, New Point(0, 0))
Dim rect As New Rectangle(New Point(0, 0), bm.Size)
Dim bitmapData As System.Drawing.Imaging.BitmapData = bm.LockBits(rect, Imaging.ImageLockMode.ReadWrite, System.Drawing.Imaging.PixelFormat.Format32bppArgb)
Dim ptr As IntPtr = bitmapData.Scan0
Dim byteCount As Integer = bitmapData.Stride * bitmapData.Height
Dim argb(byteCount - 1) As Byte
System.Runtime.InteropServices.Marshal.Copy(ptr, argb, 0, byteCount)
For i As Integer = 0 To byteCount - 1 Step 4
Dim alpha As Decimal = argb(i + 3)
Dim red As Decimal = argb(i + 2)
Dim green As Decimal = argb(i + 1)
Dim blue As Decimal = argb(i)
Dim percentR As Decimal = (red / 255) * 100
Dim percentG As Decimal = (green / 255) * 100
Dim percentB As Decimal = (blue / 255) * 100
Dim aboveThresholdCount As Integer = 0
If percentR > threshold Then aboveThresholdCount += 1
If percentG > threshold Then aboveThresholdCount += 1
If percentB > threshold Then aboveThresholdCount += 1
If aboveThresholdCount = 3 Then
red = red * modTimes
green = green * modTimes
blue = blue * modTimes
If red > 255 Then red = 255
If green > 255 Then green = 255
If blue > 255 Then blue = 255
End If
argb(i + 2) = CByte(Math.Round(red, 0))
argb(i + 1) = CByte(Math.Round(green, 0))
argb(i) = CByte(Math.Round(blue, 0))
Next
System.Runtime.InteropServices.Marshal.Copy(argb, 0, ptr, byteCount)
bm.UnlockBits(bitmapData)
Return bm
End Function
Private Sub PictureBox1_MouseMove(sender As Object, e As MouseEventArgs) Handles PictureBox1.MouseMove
Dim intersectionRect As New Rectangle(13, 18, 22, 21)
Dim mouseRect As New Rectangle(PictureBox1.PointToClient(MousePosition), New Size(1, 1))
Me.Text = mouseRect.ToString
If intersectionRect.IntersectsWith(mouseRect) Then
Dim tmp As Bitmap = BrightenPixels(originalPic, 33, 1.5D)
'---------------------Delete this section of code(inbetween lines) to remove circular highlight----------'
Using g As Graphics = Graphics.FromImage(tmp)
Using gp As New System.Drawing.Drawing2D.GraphicsPath
gp.AddRectangle(intersectionRect)
Using pgp As New System.Drawing.Drawing2D.PathGradientBrush(gp)
Dim center As New PointF(intersectionRect.Left + (intersectionRect.Width \ 2), intersectionRect.Top + (intersectionRect.Height \ 2))
pgp.CenterPoint = center
pgp.CenterColor = Color.FromArgb(64, Color.White)
pgp.SurroundColors = {Color.FromArgb(0, Color.White), Color.FromArgb(0, Color.White)}
g.FillPath(pgp, gp)
End Using
End Using
End Using
'-----------------------------------------------------------------------------------------------------------'
PictureBox1.Image = tmp
Else
PictureBox1.Image = originalPic
End If
End Sub
End Class
示例 2（图像 sh运行ken by 50%）：
Option Strict On
Option Explicit On
Option Infer Off
Public Class Form1
Private originalPic As Bitmap = Nothing
Private intersectionPic As Bitmap = Nothing
Private intersectionRect As New Rectangle(6, 9, 11, 10)
Friend WithEvents PictureBox1 As New PictureBox With {.Parent = Me, .Location = New Point(10, 10)}
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
'Only modify this line to the location of your "x" image'
Dim exPath As String = System.IO.Path.Combine(My.Computer.FileSystem.SpecialDirectories.Desktop, "picexample.jpg")
AddHandler PictureBox1.MouseMove, AddressOf PictureBox1_MouseMove
If System.IO.File.Exists(exPath) Then
Dim img As Bitmap = CType(Image.FromFile(exPath), Bitmap)
Dim bm As New Bitmap(img.Width \ 2, img.Height \ 2, System.Drawing.Imaging.PixelFormat.Format32bppArgb)
Dim g1 As Graphics = Graphics.FromImage(bm)
Dim cRect As New Rectangle(New Point(0, 0), bm.Size)
g1.DrawImage(CType(Image.FromFile(exPath), Bitmap), cRect)
originalPic = bm
Dim tmp As Bitmap = BrightenPixels(originalPic, 33, 1.5D)
'---------------------Delete this section of code(inbetween lines) to remove circular highlight----------'
Using g2 As Graphics = Graphics.FromImage(tmp)
Using gp As New System.Drawing.Drawing2D.GraphicsPath
gp.AddRectangle(intersectionRect)
Using pgp As New System.Drawing.Drawing2D.PathGradientBrush(gp)
Dim center As New PointF(intersectionRect.Left + (intersectionRect.Width \ 2), intersectionRect.Top + (intersectionRect.Height \ 2))
pgp.CenterPoint = center
pgp.CenterColor = Color.FromArgb(128, Color.White)
pgp.SurroundColors = {Color.FromArgb(0, Color.White), Color.FromArgb(0, Color.White)}
g2.FillPath(pgp, gp)
End Using
End Using
End Using
'-----------------------------------------------------------------------------------------------------------'
intersectionPic = tmp
PictureBox1.Size = originalPic.Size
PictureBox1.Image = originalPic
Else
Application.Exit()
End If
End Sub
Public Function BrightenPixels(ByVal Image As Bitmap, threshold As Decimal, modTimes As Decimal) As Bitmap
modTimes = Math.Abs(modTimes)
If Image Is Nothing Then Return Nothing
Dim bm As New Bitmap(Image.Width, Image.Height, System.Drawing.Imaging.PixelFormat.Format32bppArgb)
Dim g As Graphics = Graphics.FromImage(bm)
g.DrawImage(Image, New Point(0, 0))
Dim rect As New Rectangle(New Point(0, 0), bm.Size)
Dim bitmapData As System.Drawing.Imaging.BitmapData = bm.LockBits(rect, Imaging.ImageLockMode.ReadWrite, System.Drawing.Imaging.PixelFormat.Format32bppArgb)
Dim ptr As IntPtr = bitmapData.Scan0
Dim byteCount As Integer = bitmapData.Stride * bitmapData.Height
Dim argb(byteCount - 1) As Byte
System.Runtime.InteropServices.Marshal.Copy(ptr, argb, 0, byteCount)
For i As Integer = 0 To byteCount - 1 Step 4
Dim alpha As Decimal = argb(i + 3)
Dim red As Decimal = argb(i + 2)
Dim green As Decimal = argb(i + 1)
Dim blue As Decimal = argb(i)
Dim percentR As Decimal = (red / 255) * 100
Dim percentG As Decimal = (green / 255) * 100
Dim percentB As Decimal = (blue / 255) * 100
Dim aboveThresholdCount As Integer = 0
If percentR > threshold Then aboveThresholdCount += 1
If percentG > threshold Then aboveThresholdCount += 1
If percentB > threshold Then aboveThresholdCount += 1
If aboveThresholdCount = 3 Then
red = red * modTimes
green = green * modTimes
blue = blue * modTimes
If red > 255 Then red = 255
If green > 255 Then green = 255
If blue > 255 Then blue = 255
End If
argb(i + 2) = CByte(Math.Round(red, 0))
argb(i + 1) = CByte(Math.Round(green, 0))
argb(i) = CByte(Math.Round(blue, 0))
Next
System.Runtime.InteropServices.Marshal.Copy(argb, 0, ptr, byteCount)
bm.UnlockBits(bitmapData)
Return bm
End Function
Private Sub PictureBox1_MouseMove(sender As Object, e As MouseEventArgs) Handles PictureBox1.MouseMove
Dim mouseRect As New Rectangle(PictureBox1.PointToClient(MousePosition), New Size(1, 1))
Me.Text = mouseRect.ToString
If intersectionRect.IntersectsWith(mouseRect) Then
PictureBox1.Image = intersectionPic
Else
PictureBox1.Image = originalPic
End If
End Sub
End Class