TransparentJPG NoJpgLib -TizzyT

Imports System.IO
Imports System.Drawing
Imports System.Drawing.Imaging
Imports System.Runtime.InteropServices

Public Class TransparentJPG
    Private Shared ReadOnly _Magic() As Byte = {&H71, &H22, &H47, &H0}
    Private Shared ReadOnly JMAGIC() As Byte = {&HFF, &HD8, &HFF, &HE0}
    Private _Image As Bitmap

    Public ReadOnly Property Width() As Integer
        Get
            Return _Image.Width
        End Get
    End Property

    Public ReadOnly Property Height() As Integer
        Get
            Return _Image.Height
        End Get
    End Property

    Public Shared Sub SaveTJPG(ByVal Path As String, ByRef Image As Bitmap, Optional Quality As Long = 75)
        Dim RBitmap As New Bitmap(Image.Width, Image.Height * 2)
        Dim G As Graphics = Graphics.FromImage(RBitmap)
        G.DrawImage(Image, New Rectangle(0, 0, Image.Width, Image.Height))
        G.DrawImage(Image, New Rectangle(0, Image.Height, Image.Width, Image.Height))
        G.Dispose()
        Dim bitmapData As BitmapData = RBitmap.LockBits(New Rectangle(0, 0, RBitmap.Width, RBitmap.Height), _
                                                        ImageLockMode.ReadWrite, RBitmap.PixelFormat)
        Dim Iptr = bitmapData.Scan0
        Dim Pixels(RBitmap.Width * RBitmap.Height * 4 - 1) As Byte
        Marshal.Copy(Iptr, Pixels, 0, Pixels.Length)
        Dim AlphaPos As Integer = 3
        For i = Pixels.Length / 2 To Pixels.Length - 1 Step 4
            Dim A As Byte = Pixels(AlphaPos)
            Pixels(AlphaPos) = 255
            Pixels(i) = A
            Pixels(i + 1) = A
            Pixels(i + 2) = A
            Pixels(i + 3) = 255
            AlphaPos += 4
        Next
        Marshal.Copy(Pixels, 0, Iptr, Pixels.Length)
        RBitmap.UnlockBits(bitmapData)
        Using ms As New MemoryStream
            Dim qualityParam As New EncoderParameter(Encoder.Quality, Quality)
            Dim encoderParams As New EncoderParameters(1)
            encoderParams.Param(0) = qualityParam
            Dim codecs As ImageCodecInfo() = ImageCodecInfo.GetImageEncoders()
            For i As Integer = 0 To codecs.Length - 1
                If (codecs(i).MimeType = "image/jpeg") Then
                    RBitmap.Save(ms, codecs(i), encoderParams)
                    RBitmap.Dispose()
                    ms.Flush()
                    Dim Data() As Byte = ms.GetBuffer.Skip(10).ToArray
                    Using fs As New FileStream(Path, FileMode.Create)
                        fs.Write(_Magic, 0, _Magic.Length)
                        fs.Write(Data, 0, Data.Length)
                        fs.Flush()
                        fs.Close()
                    End Using
                End If
            Next
            ms.Close()
        End Using
    End Sub

    Public Sub New(ByVal Path As String)
        Dim SourceData() As Byte = System.IO.File.ReadAllBytes(Path)
        For i = 0 To 3
            SourceData(i) = JMAGIC(i)
        Next
        Dim MainBM As Image
        Using ms As New MemoryStream(SourceData)
            MainBM = Image.FromStream(ms)
            ms.Close()
        End Using
        Dim HalfHeight As Integer = MainBM.Height / 2
        Using Colors As New Bitmap(MainBM.Width, HalfHeight)
            Using Alphas As New Bitmap(MainBM.Width, HalfHeight)
                Dim PixelCount As Integer = Colors.Width * Colors.Height * 4 - 1
                Dim G As Graphics = Graphics.FromImage(Colors)
                G.DrawImage(MainBM, New Rectangle(0, 0, MainBM.Width, MainBM.Height))
                G = Graphics.FromImage(Alphas)
                G.DrawImage(MainBM, New Rectangle(0, 0 - HalfHeight, MainBM.Width, MainBM.Height))
                G.Dispose()
                MainBM.Dispose()
                Dim ColorbitmapData As BitmapData = _
                    Colors.LockBits(New Rectangle(0, 0, Colors.Width, Colors.Height), _
                                    ImageLockMode.ReadWrite, Colors.PixelFormat)
                Dim ColorPixels(PixelCount) As Byte
                Dim ColorIptr As IntPtr = ColorbitmapData.Scan0
                Marshal.Copy(ColorIptr, ColorPixels, 0, ColorPixels.Length)
                Dim AlphaDepth As Integer = System.Drawing.Bitmap.GetPixelFormatSize(Alphas.PixelFormat)
                Dim AlphabitmapData As BitmapData = _
                    Alphas.LockBits(New Rectangle(0, 0, Alphas.Width, Alphas.Height), _
                                    ImageLockMode.ReadWrite, Alphas.PixelFormat)
                Dim AlphaPixels(PixelCount) As Byte
                Dim AlphaIptr As IntPtr = AlphabitmapData.Scan0
                Marshal.Copy(AlphaIptr, AlphaPixels, 0, AlphaPixels.Length)
                For i = 0 To AlphaPixels.Length - 1 Step 4
                    Dim A As Single = AlphaPixels(i)
                    A += AlphaPixels(i + 1)
                    A += AlphaPixels(i + 2)
                    ColorPixels(i + 3) = Math.Round(A / 3)
                Next
                Marshal.Copy(ColorPixels, 0, ColorIptr, ColorPixels.Length)
                Marshal.Copy(AlphaPixels, 0, AlphaIptr, AlphaPixels.Length)
                Colors.UnlockBits(ColorbitmapData)
                Alphas.UnlockBits(AlphabitmapData)
                Alphas.Dispose()
                _Image = Colors.Clone
                Colors.Dispose()
            End Using
        End Using
    End Sub

    Public Shared Sub Decode(ByVal Data() As Byte, _
                             ByRef Pixels() As Byte, ByRef Width As Integer, ByRef Height As Integer)
        For i = 0 To 3
            Data(i) = JMAGIC(i)
        Next
        Dim MainBM As Image
        Using ms As New MemoryStream(Data)
            MainBM = Image.FromStream(ms)
            ms.Close()
        End Using
        Dim HalfHeight As Integer = MainBM.Height / 2
        Using Colors As New Bitmap(MainBM.Width, HalfHeight)
            Using Alphas As New Bitmap(MainBM.Width, HalfHeight)
                Dim PixelCount As Integer = Colors.Width * Colors.Height * 4 - 1
                Dim G As Graphics = Graphics.FromImage(Colors)
                G.DrawImage(MainBM, New Rectangle(0, 0, MainBM.Width, MainBM.Height))
                G = Graphics.FromImage(Alphas)
                G.DrawImage(MainBM, New Rectangle(0, 0 - HalfHeight, MainBM.Width, MainBM.Height))
                G.Dispose()
                MainBM.Dispose()
                Dim ColorbitmapData As BitmapData = _
                    Colors.LockBits(New Rectangle(0, 0, Colors.Width, Colors.Height), _
                                    ImageLockMode.ReadWrite, Colors.PixelFormat)
                Dim ColorPixels(PixelCount) As Byte
                Dim ColorIptr As IntPtr = ColorbitmapData.Scan0
                Marshal.Copy(ColorIptr, ColorPixels, 0, ColorPixels.Length)
                Dim AlphaDepth As Integer = System.Drawing.Bitmap.GetPixelFormatSize(Alphas.PixelFormat)
                Dim AlphabitmapData As BitmapData = _
                    Alphas.LockBits(New Rectangle(0, 0, Alphas.Width, Alphas.Height), _
                                    ImageLockMode.ReadWrite, Alphas.PixelFormat)
                Dim AlphaPixels(PixelCount) As Byte
                Dim AlphaIptr As IntPtr = AlphabitmapData.Scan0
                Marshal.Copy(AlphaIptr, AlphaPixels, 0, AlphaPixels.Length)
                For i = 0 To AlphaPixels.Length - 1 Step 4
                    Dim A As Single = AlphaPixels(i)
                    A += AlphaPixels(i + 1)
                    A += AlphaPixels(i + 2)
                    ColorPixels(i + 3) = Math.Round(A / 3)
                Next
                Marshal.Copy(ColorPixels, 0, ColorIptr, ColorPixels.Length)
                Marshal.Copy(AlphaPixels, 0, AlphaIptr, AlphaPixels.Length)
                Colors.UnlockBits(ColorbitmapData)
                Alphas.UnlockBits(AlphabitmapData)
                Pixels = ColorPixels
                Width = Colors.Width
                Height = Colors.Height
                Colors.Dispose()
                Alphas.Dispose()
            End Using
        End Using
    End Sub

    Public Shared Function LoadTJPG(ByVal Path As String) As Bitmap
        Dim SourceData() As Byte = System.IO.File.ReadAllBytes(Path)
        For i = 0 To 3
            SourceData(i) = JMAGIC(i)
        Next
        Dim MainBM As Image
        Using ms As New MemoryStream(SourceData)
            MainBM = Image.FromStream(ms)
            ms.Close()
        End Using
        Dim HalfHeight As Integer = MainBM.Height / 2
        Using Colors As New Bitmap(MainBM.Width, HalfHeight)
            Using Alphas As New Bitmap(MainBM.Width, HalfHeight)
                Dim PixelCount As Integer = Colors.Width * Colors.Height * 4 - 1
                Dim G As Graphics = Graphics.FromImage(Colors)
                G.DrawImage(MainBM, New Rectangle(0, 0, MainBM.Width, MainBM.Height))
                G = Graphics.FromImage(Alphas)
                G.DrawImage(MainBM, New Rectangle(0, 0 - HalfHeight, MainBM.Width, MainBM.Height))
                G.Dispose()
                MainBM.Dispose()
                Dim ColorbitmapData As BitmapData = _
                    Colors.LockBits(New Rectangle(0, 0, Colors.Width, Colors.Height), _
                                    ImageLockMode.ReadWrite, Colors.PixelFormat)
                Dim ColorPixels(PixelCount) As Byte
                Dim ColorIptr As IntPtr = ColorbitmapData.Scan0
                Marshal.Copy(ColorIptr, ColorPixels, 0, ColorPixels.Length)
                Dim AlphaDepth As Integer = System.Drawing.Bitmap.GetPixelFormatSize(Alphas.PixelFormat)
                Dim AlphabitmapData As BitmapData = _
                    Alphas.LockBits(New Rectangle(0, 0, Alphas.Width, Alphas.Height), _
                                    ImageLockMode.ReadWrite, Alphas.PixelFormat)
                Dim AlphaPixels(PixelCount) As Byte
                Dim AlphaIptr As IntPtr = AlphabitmapData.Scan0
                Marshal.Copy(AlphaIptr, AlphaPixels, 0, AlphaPixels.Length)
                For i = 0 To AlphaPixels.Length - 1 Step 4
                    Dim A As Single = AlphaPixels(i)
                    A += AlphaPixels(i + 1)
                    A += AlphaPixels(i + 2)
                    ColorPixels(i + 3) = Math.Round(A / 3)
                Next
                Marshal.Copy(ColorPixels, 0, ColorIptr, ColorPixels.Length)
                Marshal.Copy(AlphaPixels, 0, AlphaIptr, AlphaPixels.Length)
                Colors.UnlockBits(ColorbitmapData)
                Alphas.UnlockBits(AlphabitmapData)
                Alphas.Dispose()
                LoadTJPG = Colors.Clone
                Colors.Dispose()
            End Using
        End Using
    End Function

    Public Shared Widening Operator CType(ByVal TJPG As TransparentJPG) As Bitmap
        Return TJPG._Image
    End Operator

    Public ReadOnly Property ImageStream() As Stream
        Get
            Dim ms As New MemoryStream
            _Image.Save(ms, Drawing.Imaging.ImageFormat.Png)
            ms.Flush()
            Return ms
        End Get
    End Property

    Public Sub Dispose()
        _Image.Dispose()
    End Sub
End Class