CODEWITHSUNDEEP
vb.netvisual-studio-2010imagesql-server-2008
Sai Sunder
Sai Sunder

Reputation: 1021

Storing and retrieving images in Database

Here is the code I used to store an image in my database (SQL Server 2008 R2) using VB 2010. The images get stored but the problem is the clarity of the image is lost when retrieved and seen in a picture box.

Public Function InsertUpdateImage(ByRef _SqlConnection As System.Data.SqlClient.SqlConnection, ByVal _Image As System.Drawing.Image, ByVal _ImageFormat As System.Drawing.Imaging.ImageFormat) As Integer
    Dim _SqlRetVal As Integer = 0
    'System.IO.Path.GetFullPath(files(ListView1.SelectedIndices(0))) Give the path for the 'image from listview 
    Dim str As String = System.IO.Path.GetFullPath(files(ListView1.SelectedIndices(0)))
    Dim i As Integer = Len(str)
    Dim j As Integer = 0
    Dim locstr(i + 10) As Char
    i = 0
    While i < Len(str)
        If str(i) = "\" Then
            locstr(j) = "\"
            j = j + 1
        Else
            locstr(j) = str(i)
            j = j + 1
        End If
        i = i + 1
    End While
    Dim loc As New String(locstr)
    MsgBox(loc)

    ' lets add this record to database
    Dim _SqlCommand As New System.Data.SqlClient.SqlCommand("insert into maindb(photo,name,location) values(@image,'" + System.IO.Path.GetFileName(files(ListView1.SelectedIndices(0))) + "','" + loc + "')", _SqlConnection)

    ' Convert image to memory stream
    Dim _MemoryStream As New System.IO.MemoryStream()
    _Image.Save(_MemoryStream, _ImageFormat)

    ' Add image as SQL parameter
    Dim _SqlParameter As New System.Data.SqlClient.SqlParameter("@image", SqlDbType.Image)
    _SqlParameter.Value = _MemoryStream.ToArray()

    _SqlCommand.Parameters.Add(_SqlParameter)

    ' Executes a Transact-SQL statement against the connection 
    ' and returns the number of rows affected.
    _SqlRetVal = _SqlCommand.ExecuteNonQuery()
    Console.Write(_SqlRetVal)
    ' Dispose command
    _SqlCommand.Dispose()
    _SqlCommand = Nothing

    ' Error occurred while trying to execute reader
    ' send error message to console (change below line to customize error handling)

    Return _SqlRetVal
End Function

Upvotes: 0

Views: 1660

Answers (1)

JonAlb
JonAlb

Reputation: 1720

Your image.save() reduces the quality of the image (if saved as Jpeg) to the default compression level of aabout 75%.

Please see this MSDN article on increasing this quality level, when you call Save by passing in myEncoderParameters, containing a quality level at a much higher level (say 90%)

http://msdn.microsoft.com/en-us/library/system.drawing.imaging.encoder.quality.aspx

Or see the (untested) code below, that should do the trick

    ' Create a a single encoder parameter envelope
    Dim EncoderParameters As New EncoderParameters(1)

    ' Create and add a single quality parameter to this envelope, specifying 95%
    Dim QualityParam As New EncoderParameter(Encoder.Quality, CType(95L, Int32))
    EncoderParameters.Param(0) = QualityParam

    ' Save the image with the encoder param specifying 95% quality
    _image.Save(_MemoryStream, _ImageFormat, EncoderParameters)

Upvotes: 1

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