Help with Network/Web Cam active

[Ray]

I'm using VB6, I am a little more then a novice but not much..
and my question is - Is there a way to detect and possibly notify
(me/mycomputer) if someone is using a Web Cam mainly MSN on my LAN with out
the user knowing it? Even if I have to install software on the user
computer..

I not sure if this is the right way to go about this

I can get the WM_CAP_DRIVER_C ONNECT to return a True/False but this brings
up a (Video Source window) if False, I just want the value (T/F)

I am unable to get the WM_CAP_GET_STAT US to work.

Any help or sources would be appreciated.

Thanks..
Ray

[Randy Birch]

I don't think that's what you want ... the MSDN states that particular
message is used to retrieve the status of the capture window -- the
CAPSTATUS structure contains information regarding the dimensions of the
image, scroll position, and whether overlay or preview of the image is
enabled.

This of course presumes that there is a capture window on-screen.

As far as the calling syntax, that looks like it should be a simple
SendMessage call. I don't have a camera, but off the top of my head I'd be
inclined to start with:

const WM_CAP_GET_STAT US = whatever value it is

Private Type POINTAPI
x As Long
y As Long
End Type

Private Type CAPSTATUS
uiImageWidth As Long
uiImageHeight As Long
fLiveWindow As Long
fOverlayWindow As Long
fScale As Long
ptScroll As POINTAPI
fUsingDefaultPa lette As Long
fAudioHardware As Long
fCapFileExists As Long
dwCurrentVideoF rame As Long
dwCurrentVideoF ramesDropped As Long
dwCurrentWaveSa mples As Long
dwCurrentTimeEl apsedMS As Long
hPalCurrent As Long
fCapturingNow As Long
dwReturn As Long
wNumVideoAlloca ted As Long
UINT wNumAudioAlloca ted
End Type

Private Declare Function SendMessage Lib "user32" _
Alias "SendMessag eA" _
(ByVal hWnd As Long, _
ByVal wMsg As Long, _
ByVal wParam As Long, _
lParam As Any) As Long

dim success as long
dim cap as CAPSATUS

success = sendmessage (hwnd, wm_cap_get_stat us, len(cap), cap)

if success <> 0 then
? "it worked"
? cap.uiImageWidt h
? cap.uiImageHeig ht
end if

The problem is the hwnd parameter ... no idea what to put there.

I'm wondering, reading the MSDN, if the WM_CAP_DRIVER_G ET_NAME message may
not be more appropriate? Its description is "returns the name of the
capture driver connected to the capture window." This implies to me that if
the capture window exists and is connected to a device you get a name, and
if it does not exist you get no info.

There's also WM_CAP_GET_SEQU ENCE_SETUP -- "retrieves the current settings of
the streaming capture parameters" into a CAPTUREPARAMS structure containing
info such as dwMCIStartTime and dwMCIStopTime.

Problem here again though is in order to use SendMessage you have to direct
it to the hwnd of the capture window. A catch-22.

I also wonder if this is the path to go down? After all, a web cam can be
in use without a media player (for example) session on screen. It seems to
me these messages target the GUI aspect of video, not the use of a web cam.

I guess you're looking for the equivalent of a "WM_IS_CAMERA_I N_USE"
message, which I don't see as being available.

--
Randy Birch
MS MVP Visual Basic
http://vbnet.mvps.org/
"Ray" <[e-mail]> wrote in message
news:UK******** ************@ad elphia.com...
: I'm using VB6, I am a little more then a novice but not much..
: and my question is - Is there a way to detect and possibly notify
: (me/mycomputer) if someone is using a Web Cam mainly MSN on my LAN with
out
: the user knowing it? Even if I have to install software on the user
: computer..
:
: I not sure if this is the right way to go about this
:
: I can get the WM_CAP_DRIVER_C ONNECT to return a True/False but this brings
: up a (Video Source window) if False, I just want the value (T/F)
:
: I am unable to get the WM_CAP_GET_STAT US to work.
:
: Any help or sources would be appreciated.
:
: Thanks..
: Ray
:
:

[Ray]

Hi Randy,
I tried your program, But I got an error..
Statement invalid inside Type Block
(UINT wNumAudioAlloca ted )

Thanks for your time to help...
Ray

const WM_CAP_GET_STAT US = 54 <--- (I believe)

Private Type POINTAPI
x As Long
y As Long
End Type

Private Type CAPSTATUS
uiImageWidth As Long
uiImageHeight As Long
fLiveWindow As Long
fOverlayWindow As Long
fScale As Long
ptScroll As POINTAPI
fUsingDefaultPa lette As Long
fAudioHardware As Long
fCapFileExists As Long
dwCurrentVideoF rame As Long
dwCurrentVideoF ramesDropped As Long
dwCurrentWaveSa mples As Long
dwCurrentTimeEl apsedMS As Long
hPalCurrent As Long
fCapturingNow As Long
dwReturn As Long
wNumVideoAlloca ted As Long
--> UINT wNumAudioAlloca ted <------------------
End Type

Private Declare Function SendMessage Lib "user32" _
Alias "SendMessag eA" _
(ByVal hWnd As Long, _
ByVal wMsg As Long, _
ByVal wParam As Long, _
lParam As Any) As Long

dim success as long
dim cap as CAPSATUS

success = sendmessage (hwnd, wm_cap_get_stat us, len(cap), cap)

if success <> 0 then
? "it worked"
? cap.uiImageWidt h
? cap.uiImageHeig ht
end if

The problem is the hwnd parameter ... no idea what to put there.

I'm wondering, reading the MSDN, if the WM_CAP_DRIVER_G ET_NAME message may
not be more appropriate? Its description is "returns the name of the
capture driver connected to the capture window." This implies to me that if the capture window exists and is connected to a device you get a name, and
if it does not exist you get no info.

There's also WM_CAP_GET_SEQU ENCE_SETUP -- "retrieves the current settings of the streaming capture parameters" into a CAPTUREPARAMS structure containing info such as dwMCIStartTime and dwMCIStopTime.

Problem here again though is in order to use SendMessage you have to direct it to the hwnd of the capture window. A catch-22.

I also wonder if this is the path to go down? After all, a web cam can be
in use without a media player (for example) session on screen. It seems to
me these messages target the GUI aspect of video, not the use of a web cam.
I guess you're looking for the equivalent of a "WM_IS_CAMERA_I N_USE"
message, which I don't see as being available.

--
Randy Birch
MS MVP Visual Basic
http://vbnet.mvps.org/
"Ray" <[e-mail]> wrote in message
news:UK******** ************@ad elphia.com...
: I'm using VB6, I am a little more then a novice but not much..
: and my question is - Is there a way to detect and possibly notify
: (me/mycomputer) if someone is using a Web Cam mainly MSN on my LAN with
out
: the user knowing it? Even if I have to install software on the user
: computer..
:
: I not sure if this is the right way to go about this
:
: I can get the WM_CAP_DRIVER_C ONNECT to return a True/False but this brings : up a (Video Source window) if False, I just want the value (T/F)
:
: I am unable to get the WM_CAP_GET_STAT US to work.
:
: Any help or sources would be appreciated.
:
: Thanks..
: Ray
:
:

[Randy Birch]

That should have been a long as well, without the UINT. Like I said, air
code.

--
Randy Birch
MS MVP Visual Basic
http://vbnet.mvps.org/
"Ray" <[e-mail]> wrote in message
news:zr******** ************@ad elphia.com...
: Hi Randy,
: I tried your program, But I got an error..
: Statement invalid inside Type Block
: (UINT wNumAudioAlloca ted )
:
: Thanks for your time to help...
: Ray
:
: > const WM_CAP_GET_STAT US = 54 <--- (I believe)
: >
: >Private Type POINTAPI
: > x As Long
: > y As Long
: > End Type
: >
: > Private Type CAPSTATUS
: > uiImageWidth As Long
: > uiImageHeight As Long
: > fLiveWindow As Long
: > fOverlayWindow As Long
: > fScale As Long
: > ptScroll As POINTAPI
: > fUsingDefaultPa lette As Long
: > fAudioHardware As Long
: > fCapFileExists As Long
: > dwCurrentVideoF rame As Long
: > dwCurrentVideoF ramesDropped As Long
: > dwCurrentWaveSa mples As Long
: > dwCurrentTimeEl apsedMS As Long
: > hPalCurrent As Long
: > fCapturingNow As Long
: > dwReturn As Long
: > wNumVideoAlloca ted As Long
: > --> UINT wNumAudioAlloca ted <------------------
: > End Type
: >
: > Private Declare Function SendMessage Lib "user32" _
: > Alias "SendMessag eA" _
: > (ByVal hWnd As Long, _
: > ByVal wMsg As Long, _
: > ByVal wParam As Long, _
: > lParam As Any) As Long
: >
: > dim success as long
: > dim cap as CAPSATUS
: >
: > success = sendmessage (hwnd, wm_cap_get_stat us, len(cap), cap)
: >
: > if success <> 0 then
: > ? "it worked"
: > ? cap.uiImageWidt h
: > ? cap.uiImageHeig ht
: > end if
: >
: > The problem is the hwnd parameter ... no idea what to put there.
: >
: > I'm wondering, reading the MSDN, if the WM_CAP_DRIVER_G ET_NAME message
may
: > not be more appropriate? Its description is "returns the name of the
: > capture driver connected to the capture window." This implies to me
that
: if
: > the capture window exists and is connected to a device you get a name,
and
: > if it does not exist you get no info.
: >
: > There's also WM_CAP_GET_SEQU ENCE_SETUP -- "retrieves the current
settings
: of
: > the streaming capture parameters" into a CAPTUREPARAMS structure
: containing
: > info such as dwMCIStartTime and dwMCIStopTime.
: >
: > Problem here again though is in order to use SendMessage you have to
: direct
: > it to the hwnd of the capture window. A catch-22.
: >
: > I also wonder if this is the path to go down? After all, a web cam can
be
: > in use without a media player (for example) session on screen. It seems
to
: > me these messages target the GUI aspect of video, not the use of a web
: cam.
: >
: > I guess you're looking for the equivalent of a "WM_IS_CAMERA_I N_USE"
: > message, which I don't see as being available.
: >
: > --
: >
: >
: > Randy Birch
: > MS MVP Visual Basic
: > http://vbnet.mvps.org/
: >
: >
: > "Ray" <[e-mail]> wrote in message
: > news:UK******** ************@ad elphia.com...
: > : I'm using VB6, I am a little more then a novice but not much..
: > : and my question is - Is there a way to detect and possibly notify
: > : (me/mycomputer) if someone is using a Web Cam mainly MSN on my LAN
with
: > out
: > : the user knowing it? Even if I have to install software on the user
: > : computer..
: > :
: > : I not sure if this is the right way to go about this
: > :
: > : I can get the WM_CAP_DRIVER_C ONNECT to return a True/False but this
: brings
: > : up a (Video Source window) if False, I just want the value (T/F)
: > :
: > : I am unable to get the WM_CAP_GET_STAT US to work.
: > :
: > : Any help or sources would be appreciated.
: > :
: > : Thanks..
: > : Ray
: > :
: > :
: >
:
:

[Ray]

Randy ,
I think I got the code right but it not working this is what I have so far.

Ray

3 text boxes 1 command button

Const WM_CAP As Integer = &H400

Const WM_CAP_GET_STAT US As Long = WM_CAP + 54

Private Type POINTAPI
x As Long
y As Long
End Type

Private Type CAPSTATUS
uiImageWidth As Long
uiImageHeight As Long
fLiveWindow As Long
fOverlayWindow As Long
fScale As Long
ptScroll As POINTAPI
fUsingDefaultPa lette As Long
fAudioHardware As Long
fCapFileExists As Long
dwCurrentVideoF rame As Long
dwCurrentVideoF ramesDropped As Long
dwCurrentWaveSa mples As Long
dwCurrentTimeEl apsedMS As Long
hPalCurrent As Long
fCapturingNow As Long
dwReturn As Long
wNumVideoAlloca ted As Long
wNumAudioAlloca ted As Long
End Type

Private Declare Function SendMessage Lib "user32" Alias "SendMessag eA" _
(ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, _
lParam As Any) As Long

Dim cap As CAPSTATUS

Private Sub Command1_Click( )
Dim success As Long

success = SendMessage(hwn d, WM_CAP_GET_STAT US, Len(cap), cap)

If success <> 0 Then
Text1.Text = "True"
Text2.Text = cap.uiImageWidt h
Text3.Text = cap.uiImageHeig ht
Else
Text1.Text = "False"
Text2.Text = 0
Text3.Text = 0
End If
End Sub

[Randy Birch]

Right ... that's what I meant about hwnd. In the context you use it, hwnd
without any qualifier or declaration refers to the hwnd of the form the code
is executing in. I suspect that what is required is the hwnd to some sort
of capture window, which I stated I had no idea how to obtain. I suspect
that you will not be able to do what you want ... like I said, you want a
IS_CAMERA_IN_US E message which simply doesn't exist that I can see (in a
quick scan of the msdn). You might want to ask in the multimedia groups or
possibly the visual C group for recommendations on whether this is even
possible. Those guys in the C group would be able to tell you if it is ...
don't expect VB code from them but with a snippet of C code you at least
have a starting point. My demo was to show you what I *suspected* the code
you requested might look like in VB. Without a camera to test it, the code
was only an educated guess.

If you decide to post to the C group (or the SDK group who operate on an
even higher level than the C gang) I would phrase the question as: Does
anyone know if there is a notification broadcast, or alternatively a message
that can be sent to the system, that would inform me that a web camera
attached to the local computer was in use, or not?

--
Randy Birch
MS MVP Visual Basic
http://vbnet.mvps.org/
"Ray" <[e-mail]> wrote in message
news:VL******** ************@ad elphia.com...
: Randy ,
: I think I got the code right but it not working this is what I have so
far.
:
: Ray
:
: 3 text boxes 1 command button
:
: Const WM_CAP As Integer = &H400
:
: Const WM_CAP_GET_STAT US As Long = WM_CAP + 54
:
: Private Type POINTAPI
: x As Long
: y As Long
: End Type
:
: Private Type CAPSTATUS
: uiImageWidth As Long
: uiImageHeight As Long
: fLiveWindow As Long
: fOverlayWindow As Long
: fScale As Long
: ptScroll As POINTAPI
: fUsingDefaultPa lette As Long
: fAudioHardware As Long
: fCapFileExists As Long
: dwCurrentVideoF rame As Long
: dwCurrentVideoF ramesDropped As Long
: dwCurrentWaveSa mples As Long
: dwCurrentTimeEl apsedMS As Long
: hPalCurrent As Long
: fCapturingNow As Long
: dwReturn As Long
: wNumVideoAlloca ted As Long
: wNumAudioAlloca ted As Long
: End Type
:
: Private Declare Function SendMessage Lib "user32" Alias "SendMessag eA" _
: (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, _
: lParam As Any) As Long
:
: Dim cap As CAPSTATUS
:
: Private Sub Command1_Click( )
: Dim success As Long
:
: success = SendMessage(hwn d, WM_CAP_GET_STAT US, Len(cap), cap)
:
: If success <> 0 Then
: Text1.Text = "True"
: Text2.Text = cap.uiImageWidt h
: Text3.Text = cap.uiImageHeig ht
: Else
: Text1.Text = "False"
: Text2.Text = 0
: Text3.Text = 0
: End If
:
:
: End Sub
:
:
:
:

[Ray]

Randy,

Thanks for all of your help, I'm not sure where to find the
groups you spoke of but I will try to find them and post a message.

Thanks Again,

Ray

"Randy Birch" <rg************ @mvps.org> wrote in message
news:Oa******** ************@ro gers.com...

Right ... that's what I meant about hwnd. In the context you use it, hwnd
without any qualifier or declaration refers to the hwnd of the form the
code
is executing in. I suspect that what is required is the hwnd to some sort
of capture window, which I stated I had no idea how to obtain. I suspect
that you will not be able to do what you want ... like I said, you want a
IS_CAMERA_IN_US E message which simply doesn't exist that I can see (in a
quick scan of the msdn). You might want to ask in the multimedia groups
or
possibly the visual C group for recommendations on whether this is even
possible. Those guys in the C group would be able to tell you if it is
...
don't expect VB code from them but with a snippet of C code you at least
have a starting point. My demo was to show you what I *suspected* the
code
you requested might look like in VB. Without a camera to test it, the code
was only an educated guess.

If you decide to post to the C group (or the SDK group who operate on an
even higher level than the C gang) I would phrase the question as: Does
anyone know if there is a notification broadcast, or alternatively a
message
that can be sent to the system, that would inform me that a web camera
attached to the local computer was in use, or not?

--
Randy Birch
MS MVP Visual Basic
http://vbnet.mvps.org/
"Ray" <[e-mail]> wrote in message
news:VL******** ************@ad elphia.com...
: Randy ,
: I think I got the code right but it not working this is what I have so
far.
:
: Ray
:
: 3 text boxes 1 command button
:
: Const WM_CAP As Integer = &H400
:
: Const WM_CAP_GET_STAT US As Long = WM_CAP + 54
:
: Private Type POINTAPI
: x As Long
: y As Long
: End Type
:
: Private Type CAPSTATUS
: uiImageWidth As Long
: uiImageHeight As Long
: fLiveWindow As Long
: fOverlayWindow As Long
: fScale As Long
: ptScroll As POINTAPI
: fUsingDefaultPa lette As Long
: fAudioHardware As Long
: fCapFileExists As Long
: dwCurrentVideoF rame As Long
: dwCurrentVideoF ramesDropped As Long
: dwCurrentWaveSa mples As Long
: dwCurrentTimeEl apsedMS As Long
: hPalCurrent As Long
: fCapturingNow As Long
: dwReturn As Long
: wNumVideoAlloca ted As Long
: wNumAudioAlloca ted As Long
: End Type
:
: Private Declare Function SendMessage Lib "user32" Alias "SendMessag eA" _
: (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, _
: lParam As Any) As Long
:
: Dim cap As CAPSTATUS
:
: Private Sub Command1_Click( )
: Dim success As Long
:
: success = SendMessage(hwn d, WM_CAP_GET_STAT US, Len(cap), cap)
:
: If success <> 0 Then
: Text1.Text = "True"
: Text2.Text = cap.uiImageWidt h
: Text3.Text = cap.uiImageHeig ht
: Else
: Text1.Text = "False"
: Text2.Text = 0
: Text3.Text = 0
: End If
:
:
: End Sub
:
:
:
:

[Randy Birch]

Oops ... sorry. Try msnews.microsof t.com as the newsgroup server in Outlook
Express, then look for the vc or visual c or sdk groups.

--
Randy Birch
MS MVP Visual Basic
http://vbnet.mvps.org/
"Ray" <ra*@nomail.net > wrote in message
news:gL******** ************@ad elphia.com...
: Randy,
:
: Thanks for all of your help, I'm not sure where to find the
: groups you spoke of but I will try to find them and post a message.
:
:
:
: Thanks Again,
:
: Ray
:
:
:
:
:
: "Randy Birch" <rg************ @mvps.org> wrote in message
: news:Oa******** ************@ro gers.com...
: > Right ... that's what I meant about hwnd. In the context you use it,
hwnd
: > without any qualifier or declaration refers to the hwnd of the form the
: > code
: > is executing in. I suspect that what is required is the hwnd to some
sort
: > of capture window, which I stated I had no idea how to obtain. I suspect
: > that you will not be able to do what you want ... like I said, you want
a
: > IS_CAMERA_IN_US E message which simply doesn't exist that I can see (in a
: > quick scan of the msdn). You might want to ask in the multimedia groups
: > or
: > possibly the visual C group for recommendations on whether this is even
: > possible. Those guys in the C group would be able to tell you if it is
: > ...
: > don't expect VB code from them but with a snippet of C code you at least
: > have a starting point. My demo was to show you what I *suspected* the
: > code
: > you requested might look like in VB. Without a camera to test it, the
code
: > was only an educated guess.
: >
: > If you decide to post to the C group (or the SDK group who operate on an
: > even higher level than the C gang) I would phrase the question as: Does
: > anyone know if there is a notification broadcast, or alternatively a
: > message
: > that can be sent to the system, that would inform me that a web camera
: > attached to the local computer was in use, or not?
: >
: > --
: >
: >
: > Randy Birch
: > MS MVP Visual Basic
: > http://vbnet.mvps.org/
: >
: >
: > "Ray" <[e-mail]> wrote in message
: > news:VL******** ************@ad elphia.com...
: > : Randy ,
: > : I think I got the code right but it not working this is what I have
so
: > far.
: > :
: > : Ray
: > :
: > : 3 text boxes 1 command button
: > :
: > : Const WM_CAP As Integer = &H400
: > :
: > : Const WM_CAP_GET_STAT US As Long = WM_CAP + 54
: > :
: > : Private Type POINTAPI
: > : x As Long
: > : y As Long
: > : End Type
: > :
: > : Private Type CAPSTATUS
: > : uiImageWidth As Long
: > : uiImageHeight As Long
: > : fLiveWindow As Long
: > : fOverlayWindow As Long
: > : fScale As Long
: > : ptScroll As POINTAPI
: > : fUsingDefaultPa lette As Long
: > : fAudioHardware As Long
: > : fCapFileExists As Long
: > : dwCurrentVideoF rame As Long
: > : dwCurrentVideoF ramesDropped As Long
: > : dwCurrentWaveSa mples As Long
: > : dwCurrentTimeEl apsedMS As Long
: > : hPalCurrent As Long
: > : fCapturingNow As Long
: > : dwReturn As Long
: > : wNumVideoAlloca ted As Long
: > : wNumAudioAlloca ted As Long
: > : End Type
: > :
: > : Private Declare Function SendMessage Lib "user32" Alias "SendMessag eA"
_
: > : (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, _
: > : lParam As Any) As Long
: > :
: > : Dim cap As CAPSTATUS
: > :
: > : Private Sub Command1_Click( )
: > : Dim success As Long
: > :
: > : success = SendMessage(hwn d, WM_CAP_GET_STAT US, Len(cap), cap)
: > :
: > : If success <> 0 Then
: > : Text1.Text = "True"
: > : Text2.Text = cap.uiImageWidt h
: > : Text3.Text = cap.uiImageHeig ht
: > : Else
: > : Text1.Text = "False"
: > : Text2.Text = 0
: > : Text3.Text = 0
: > : End If
: > :
: > :
: > : End Sub
: > :
: > :
: > :
: > :
: >
:
: