Converting image into stream

Question

I'm using a function that uploads an image, takes the stream and resizes it using imageresizer.net, then uploads the stream to Amazon S3.

Now I want to take a local picture and convert it into a stream. (to resize and upload to amazonS3). Basically, how do you convert an image into a stream.

This might be a simple question, just could not find the answer anywhere.

Here is some basic code.

Public Shared Sub MoveToAmazon(strImg As String, SKU As String)
        Dim fullImg As String = "C:\ImageLocation\" & strImg
        Dim img As Image = Image.FromFile(fullImg)

        'Here Im missing the code to convert it to a stream.
        UploadImage(imgStream, SKU)  

End Sub


Public Shared Sub UploadImage(imgStream As Stream, imgName As String)

    Dim MainStream As Stream = New MemoryStream
    Dim HomeStream As Stream = New MemoryStream
    Dim SmallStream As Stream = New MemoryStream
    Dim TinyStream As Stream = New MemoryStream
    Dim MidStream As Stream = New MemoryStream
    Dim GridStream As Stream = New MemoryStream
    Dim ListStream As Stream = New MemoryStream


    Dim c As New ImageResizer.Configuration.Config

    Dim SourceImage As Bitmap = New Bitmap(imgStream)
    Dim SourceMain As Bitmap = New Bitmap(SourceImage)
    Dim SourceHome As Bitmap = New Bitmap(SourceImage)
    Dim SourceSmall As Bitmap = New Bitmap(SourceImage)
    Dim SourceTiny As Bitmap = New Bitmap(SourceImage)
    Dim SourceMid As Bitmap = New Bitmap(SourceImage)
    Dim SourceGrid As Bitmap = New Bitmap(SourceImage)
    Dim SourceList As Bitmap = New Bitmap(SourceImage)

    ImageResizer.ImageBuilder.Current.Build(SourceMain, MainStream, New ResizeSettings("width=300&height=372&scale=both&paddingWidth=40")) 'ProductPage
    ImageResizer.ImageBuilder.Current.Build(SourceHome, HomeStream, New ResizeSettings("width=112&height=147&scale=both")) 'HomePage Products
    ImageResizer.ImageBuilder.Current.Build(SourceGrid, GridStream, New ResizeSettings("width=149&height=149&scale=both")) 'Categories Grid
    ImageResizer.ImageBuilder.Current.Build(SourceList, ListStream, New ResizeSettings("width=171&height=206&scale=both")) 'Categories List
    ImageResizer.ImageBuilder.Current.Build(SourceSmall, SmallStream, New ResizeSettings("width=64&height=75&scale=both")) 'Accessories
    ImageResizer.ImageBuilder.Current.Build(SourceTiny, TinyStream, New ResizeSettings("width=82&height=82&scale=both")) 'Cart
    ImageResizer.ImageBuilder.Current.Build(SourceMid, MidStream, New ResizeSettings("width=155&height=116&scale=both")) 'CategoryMain


    AmazonUploadFile("OriginalImages/" & imgName, imgStream)
    AmazonUploadFile("MainImages/" & imgName, MainStream)
    AmazonUploadFile("HomeImages/" & imgName, HomeStream)
    AmazonUploadFile("GridImages/" & imgName, GridStream)
    AmazonUploadFile("ListImages/" & imgName, ListStream)
    AmazonUploadFile("SmallImages/" & imgName, SmallStream)
    AmazonUploadFile("TinyImages/" & imgName, TinyStream)
    AmazonUploadFile("MidImages/" & imgName, MidStream)
End Sub

Public Shared Sub AmazonUploadFile(S3Key As String, FileStream As Stream)
    Dim request As New PutObjectRequest()
    request.WithBucketName(BUCKET_NAME)
    request.WithKey(S3Key).InputStream = FileStream
    request.WithCannedACL(S3CannedACL.PublicRead)
    GetS3Client.PutObject(request)
End Sub

Answer 1

[Disclaimer - I'm the author of the ImageResizing.NET library the OP is asking the question about.]

Folks - do NOT use Bitmap and Image instances if you can possibly avoid it. There is a giant list of pitfalls that will crash your server. Do NOT use ANYTHING from System.Drawing without a server-safe wrapper around it.

@dash - Your code is almost right, aside from the memory leaks.

Decoding and encoding images safely isn't straightforward. Let the ImageResizing.Net library handle it.

Dim settings as New ResizeSettings("width=64&height=75&scale=both")
Using ms As New MemoryStream()
    ImageBuilder.Current.Build("C:\ImageLocation\" & strImg, ms, settings)
    ms.Seek(0, SeekOrigin.Begin) 
    UploadImage(ms, SKU)
End Using

Never load something into a Bitmap or Image instance if you're making multiple versions. Clone the file into a MemoryStream instead.

Using fs as New FileStream(...)
  Using ms as MemoryStream = Util.StreamUtils.CopyStream(fs)
     'For loop here with your setting variations
     ms.Seek(0, SeekOrigin.Begin)
     'Place upload and resize code here
     'End Loop
  End Using
End Using

Answer 2

The following code snippet should do what you want:

  Using myImage = Image.FromFile(fullImg)
    Using ms As New MemoryStream()
        myImage.Save(ms, ImageFormat.Jpeg)
        ms.Seek(0, SeekOrigin.Begin) 
        UploadImage(ms, SKU)  
    End Using
  End Using

As an aside, you might find it easier to parameterize your methods and do all the work when calling them. Something like the following may make your life easier (this assumes the code you posted is code you are actually using and not a demo):

Public Shared Sub UploadImages()
    'Call this for each image
    MoveToAmazon("C:\ImageLocation\blah.jpg", "OriginalImage", 300, 300, 0, "whatever")

End Sub


Public Shared Sub MoveToAmazon(strImg As String, targetFolder As String, height as Integer, width as Integer, padding as Integer, SKU As String)
        Dim fullImg As String = "" & strImg
        Using img = Image.FromFile(fullImg)
            'Here Im missing the code to convert it to a stream.
            Using ms As New MemoryStream()
                Image.Save(ms, ImageFormat.Jpeg)
                ms.Seek(0, SeekOrigin.Begin) 
                UploadImage(ms, SKU)  
            End Using
        End Using
End Sub


Public Shared Sub UploadImage(imgStream As Stream, imgName As String, targetFolder As String, height as Integer, width as Integer, padding as Integer, SKU As String)

    Dim c As New ImageResizer.Configuration.Config

    ImageResizer.ImageBuilder.Current.Build(SourceMain, imgStream, New ResizeSettings("width=" & CStr(width) & "&height=" & CStr(height) & "&scale=both&paddingWidth=" & CStr(padding)) 

    AmazonUploadFile(targetFolder & "/" & imgName, imgStream)

End Sub

Public Shared Sub AmazonUploadFile(S3Key As String, FileStream As Stream)
    Dim request As New PutObjectRequest()
    request.WithBucketName(BUCKET_NAME)
    request.WithKey(S3Key).InputStream = FileStream
    request.WithCannedACL(S3CannedACL.PublicRead)
    GetS3Client.PutObject(request)
End Sub


Using ms As New MemoryStream()
    Image.Save(ms, ImageFormat.Jpeg)
    ms.Seek(0, SeekOrigin.Begin) 
    UploadImage(ms, SKU)  
End Using