Εquilibrium

Get a Jpeg MemoryStream from a given bitmap and for specified compression rate

Imports System.IO 
Imports System.Drawing 
Imports System.Drawing.Imaging 

Public Module Bitmap 
    Public Function GetJpegStream(ByVal Bitmap As System.Drawing.Bitmap, ByVal Quality As Integer) As MemoryStream 
        If Bitmap Is Nothing Then Throw New Exception("No bitmap supplied for stream conversion") 
        If Quality < 0 Or Quality > 100 Then Throw New Exception("Invalid quality supplied for stream conversion") 

        Dim codecs As ImageCodecInfo() = ImageCodecInfo.GetImageEncoders() 
        Dim ici As ImageCodecInfo = Nothing 
        Dim codec As ImageCodecInfo 
        For Each codec In codecs 
            If codec.MimeType = "image/jpeg" Then 
                ici = codec 
            End If 
        Next codec 
        Dim EncoderParameters As New EncoderParameters 
        EncoderParameters.Param(0) = New EncoderParameter(Encoder.Quality, Quality) 

        Dim Stream As New MemoryStream 
        Bitmap.Save(Stream, ici, EncoderParameters) 

        Return Stream 
    End Function 
End Module