Comments by shubh2895 (Top 7 by date)

thanks for Crop code... it works....

please help

i am stuck on image brightness problem in wpf using slider control.

i tried to pass values to this function it gives error

"object reference not set to the instance of object"
Public Shared Function Brightness(ByVal image As Bitmap, ByVal SliderValue As Integer) As Bitmap

'DrawImage(image, GetBrightnessMatrix(percent))

Dim brtR As Single = CSng(SliderValue / 100)
Dim brtG As Single = CSng(SliderValue / 100)
Dim brtB As Single = CSng(SliderValue / 100)
Dim image_attr As New ImageAttributes
Dim cm As ColorMatrix = New ColorMatrix(New Single()() _
{ _
New Single() {brtR, 0.0, 0.0, 0.0, 0.0}, _
New Single() {0.0, brtG, 0.0, 0.0, 0.0}, _
New Single() {0.0, 0.0, brtB, 0.0, 0.0}, _
New Single() {0.0, 0.0, 0.0, 1.0, 0.0}, _
New Single() {0.0, 0.0, 0.0, 0.0, 1.0}})

Dim rect As Rectangle = _
Rectangle.Round(image.GetBounds(GraphicsUnit.Pixel))
Dim wid As Integer = image.Width
Dim hgt As Integer = image.Height

Dim img As New Bitmap(wid, hgt)
Dim gr As Graphics = Graphics.FromImage(img)

image_attr.SetColorMatrix(cm)
gr.DrawImage(image, rect, 0, 0, wid, _
hgt, GraphicsUnit.Pixel, image_attr)

Return img


End Function


Private Sub SliderBrightness_ValueChanged(ByVal sender As System.Object, ByVal e As System.Windows.RoutedPropertyChangedEventArgs(Of System.Double)) Handles SliderBrightness.ValueChanged

If image1.Source IsNot Nothing Then


Dim i As Integer
i = SliderBrightness.Value
StackPanelImage.Source = ToBitmapImage(Brightness(bitmapimage, i))
End If
End Sub

thanks for Crop code... it works....

please help

i am stuck on image brightness problem in wpf using slider control.

i tried to pass values to this function it gives error

"object reference not set to the instance of object"
Public Shared Function Brightness(ByVal image As Bitmap, ByVal SliderValue As Integer) As Bitmap

'DrawImage(image, GetBrightnessMatrix(percent))

Dim brtR As Single = CSng(SliderValue / 100)
Dim brtG As Single = CSng(SliderValue / 100)
Dim brtB As Single = CSng(SliderValue / 100)
Dim image_attr As New ImageAttributes
Dim cm As ColorMatrix = New ColorMatrix(New Single()() _
{ _
New Single() {brtR, 0.0, 0.0, 0.0, 0.0}, _
New Single() {0.0, brtG, 0.0, 0.0, 0.0}, _
New Single() {0.0, 0.0, brtB, 0.0, 0.0}, _
New Single() {0.0, 0.0, 0.0, 1.0, 0.0}, _
New Single() {0.0, 0.0, 0.0, 0.0, 1.0}})

Dim rect As Rectangle = _
Rectangle.Round(image.GetBounds(GraphicsUnit.Pixel))
Dim wid As Integer = image.Width
Dim hgt As Integer = image.Height

Dim img As New Bitmap(wid, hgt)
Dim gr As Graphics = Graphics.FromImage(img)

image_attr.SetColorMatrix(cm)
gr.DrawImage(image, rect, 0, 0, wid, _
hgt, GraphicsUnit.Pixel, image_attr)

Return img


End Function


Private Sub SliderBrightness_ValueChanged(ByVal sender As System.Object, ByVal e As System.Windows.RoutedPropertyChangedEventArgs(Of System.Double)) Handles SliderBrightness.ValueChanged

If image1.Source IsNot Nothing Then


Dim i As Integer
i = SliderBrightness.Value
StackPanelImage.Source = ToBitmapImage(Brightness(bitmapimage, i))
End If
End Sub