Getting byte size of image

[Jerry Spence1]

I am trying to come up with a focussing routine for a camera and I need to
detect when the image is in focus.

As I understand it, JPG Image size goes up sharply when it is in focus as it
is very sensitive to the presence of sharply defined edges (high spatial
frequency information). I have the following routine which gets the image
from the camera into NewPic. I am trying to find the size in bytes of this
image and I don't want to write it out to disk and read it again. I have
looked at various properties of NewPic and also respStream and I can't find
the answer.
Dim siteUri As New System.Uri(URL)
WebRequest = System.Net.WebRequest.Create(siteUri)
WebRequest.Timeout = 3000
Dim respStream As System.IO.Stream = Nothing
Dim webResponse As System.Net.WebResponse = WebRequest.GetResponse()
respStream = webResponse.GetResponseStream()
Dim NewPic As Image = Image.FromStream(respStream)

-Jerry

[=?ISO-8859-1?Q?G=F6ran_Andersson?=]

Jerry Spence1 wrote:

I am trying to come up with a focussing routine for a camera and I need to
detect when the image is in focus.

As I understand it, JPG Image size goes up sharply when it is in focus as it
is very sensitive to the presence of sharply defined edges (high spatial
frequency information). I have the following routine which gets the image
from the camera into NewPic. I am trying to find the size in bytes of this
image and I don't want to write it out to disk and read it again. I have
looked at various properties of NewPic and also respStream and I can't find
the answer.
Dim siteUri As New System.Uri(URL)
WebRequest = System.Net.WebRequest.Create(siteUri)
WebRequest.Timeout = 3000
Dim respStream As System.IO.Stream = Nothing
Dim webResponse As System.Net.WebResponse = WebRequest.GetResponse()
respStream = webResponse.GetResponseStream()
Dim NewPic As Image = Image.FromStream(respStream)

-Jerry

If you can't get the length from the WebResponse object, you can write
the stream to a MemoryStream.

--
Göran Andersson
_____
http://www.guffa.com

[Jerry Spence1]

Webresponse was the answer. Thanks very much Göran

-Jerry
"Göran Andersson" <gu***@guffa.comwrote in message
news:OL**************@TK2MSFTNGP03.phx.gbl...

Jerry Spence1 wrote:

>I am trying to come up with a focussing routine for a camera and I need
to detect when the image is in focus.

As I understand it, JPG Image size goes up sharply when it is in focus as
it is very sensitive to the presence of sharply defined edges (high
spatial frequency information). I have the following routine which gets
the image from the camera into NewPic. I am trying to find the size in
bytes of this image and I don't want to write it out to disk and read it
again. I have looked at various properties of NewPic and also respStream
and I can't find the answer.
Dim siteUri As New System.Uri(URL)
WebRequest = System.Net.WebRequest.Create(siteUri)
WebRequest.Timeout = 3000
Dim respStream As System.IO.Stream = Nothing
Dim webResponse As System.Net.WebResponse = WebRequest.GetResponse()
respStream = webResponse.GetResponseStream()
Dim NewPic As Image = Image.FromStream(respStream)

-Jerry

If you can't get the length from the WebResponse object, you can write the
stream to a MemoryStream.

--
Göran Andersson
_____
http://www.guffa.com