Simple Webcam access using Escapi

[mylise]

This is a down to earth DLL to access webcams in Direct Show. The only hick is it lacks access to webcam's adjustments.

You can find more information here: http://sol.gfxile.net/escapi/index.html

Here is a simple script showing how to use it. Have fun!

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;--------------------------------------------------------------------------
; ESCAPI is a very simple DLL interface to use video capture devices
; (most commonly webcams, but also video in devices and other similar things)
; Get dll from --> [url="http://sol.gfxile.net/escapi/index.html"]http://sol.gfxile.net/escapi/index.html[/url]
;
#include <GDIplus.au3>
#Include <GUIConstantsEx.au3>
;--------------------------------------------------------------------------
; Local variables
Local $Width = 640 ;Escapi seems to use 640x480 (or lower) as webcam resolution and will
Local $Height = 480  ; adjust the image size to $Width by $Height
;--------------------------------------------------------------------------
; variables required for dshow escapi
Local $tagSimpleCapParams = _
"ptr mTargetBuf;" & _
"int mWidth;" & _
"int mHeight;"
Local $tSimpleCapParams = DllStructCreate($tagSimpleCapParams)
Local $tTargetBuf = DllStructCreate("BYTE[" & $Width*$Height*4 & "]")
Global $pTargetBuf = DllStructGetPtr($tTargetBuf)
DllStructSetData($tSimpleCapParams, 1, $pTargetBuf)
DllStructSetData($tSimpleCapParams, 2, $Width)
DllStructSetData($tSimpleCapParams, 3, $Height)
Local $pSimpleCapParams = DllStructGetPtr($tSimpleCapParams)
Local $device = 0 ;change this number to select dshow device
;---------------------------------------------------------------------------
;Escapi init
local $_escapi_Dll = DllOpen("escapi.dll")
$return = DllCall($_escapi_Dll,"int","initCOM")
$return = DllCall($_escapi_Dll,"int:cdecl","initCapture", "int", $device, "ptr", $pSimpleCapParams)
;---------------------------------------------------------------------------
; GUI and GDI init
Global $hwnd = GUICreate("EscApi WebCam", $Width, $Height)
GUISetState(@SW_SHOW,$hwnd)
_GDIPlus_Startup()
Global $hGraphics = _GDIPlus_GraphicsCreateFromHWND($hwnd)
;---------------------------------------------------------------------------
;Get frame
DllCall($_escapi_Dll,"none:cdecl","doCapture", "int", 0)
Do
$return = DllCall($_escapi_Dll,"int:cdecl","isCaptureDone", "int", 0)
sleep(100)
Until $return[0] = 1

;---------------------------------------------------------------------------
;Display frame
$hBMP = _WinAPI_CreateBitmap($Width, $Height , 1 , 32 , $pTargetBuf)
Local $hImage = _GDIPlus_BitmapCreateFromHBITMAP($hBMP)

_GDIPlus_GraphicsDrawImageRect($hGraphics, $hImage, 0, 0, $Width, $Height)
_GDIPlus_BitmapDispose($hImage)
     _WinAPI_DeleteObject($hBMP)

While 1
Local $msg = GUIGetMsg()
If $msg = $GUI_EVENT_CLOSE Then ExitLoop
sleep(50)
WEnd
;--------------------------------------------------------------------------
;Clean up
_GDIPlus_GraphicsDispose($hGraphics)
_GDIPlus_Shutdown()
GUIDelete($hwnd)

Edited May 4, 2013 by mylise

[wakillon]

have added #Include <GUIConstantsEx.au3>

but there is an other error : ERROR: $hGraphics: undeclared global variable.

[mylise]

Thank you Wakillon for pointing out the errors. Next time I will try the scripts after cleaning them up!

I did forget two lines:

#include <GUIConstantsEx.au3>

Global $hGraphics = _GDIPlus_GraphicsCreateFromHWND($hwnd)

P.S. The script above has been edited and fixed.

Edited May 4, 2013 by mylise

[wakillon]

Thanks mylise, works well now !

if you use initCapture at start may be you must use deinitCapture at end ?

Do you have examples for countCaptureDevices, getCaptureDeviceName and ESCAPIDLLVersion functions ?

[mylise]

Yes you are right, we do need a deinitcapture at the end.

I have modified the script and I think it is all there

Have fun

[mylise]

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;--------------------------------------------------------------------------
; ESCAPI is a very simple DLL interface to use video capture devices
; (most commonly webcams, but also video in devices and other similar things)
; Get dll from --> [url="http://sol.gfxile.net/escapi/index.html"]http://sol.gfxile.net/escapi/index.html[/url]
;
#include <GDIplus.au3>
#Include <GUIConstantsEx.au3>
;--------------------------------------------------------------------------
; Local variables
Local $Width = 640 ;Escapi seems to use 640x480 (or lower) as webcam resolution and will
Local $Height = 480  ; adjust the image size to $Width by $Height
;--------------------------------------------------------------------------
; variables required for dshow escapi
Local $tagSimpleCapParams = _
"ptr mTargetBuf;" & _
"int mWidth;" & _
"int mHeight;"
Local $tSimpleCapParams = DllStructCreate($tagSimpleCapParams)
Local $tTargetBuf = DllStructCreate("BYTE[" & $Width*$Height*4 & "]")
Global $pTargetBuf = DllStructGetPtr($tTargetBuf)
DllStructSetData($tSimpleCapParams, 1, $pTargetBuf)
DllStructSetData($tSimpleCapParams, 2, $Width)
DllStructSetData($tSimpleCapParams, 3, $Height)
Local $pSimpleCapParams = DllStructGetPtr($tSimpleCapParams)
Local $device = 0 ;change this number to select dshow device
Local $sver = "--ERROR--"
Local $tCam = DllStructCreate("CHAR v[20]") ;buffer used to get ESCAPI device name
DllStructSetData($tCam, 1, $sver)
Local $pCam = DllStructGetPtr($tCam)
;---------------------------------------------------------------------------
;Escapi init and get Information
local $_escapi_Dll = DllOpen("escapi.dll")
Local $CamInfo
;ESCAPI version
$return = DllCall($_escapi_Dll,"int","ESCAPIDLLVersion")
$CamInfo &= "Dll version = " & Hex($return[0],3) & @CRLF
$return = DllCall($_escapi_Dll,"int","initCOM")
; get number of available devices
$return = DllCall($_escapi_Dll,"int","countCaptureDevices")
$CamInfo &= "Number of devices = " & $return[0] & @CRLF
; get selected device name, $device = 0
DllCall($_escapi_Dll,"none:cdecl","getCaptureDeviceName", "uint" , $device, "ptr" , $pCam  , "int" , 20)
Local $vCam = DllStructGetData($tCam , 1)
$CamInfo &= "First device name = " & $vCam & @CRLF
MsgBox(0,"ESCAPI info", $CamInfo)
$return = DllCall($_escapi_Dll,"int:cdecl","initCapture", "int", $device, "ptr", $pSimpleCapParams)
;---------------------------------------------------------------------------
; GUI and GDI init
Global $hwnd = GUICreate("EscApi WebCam", $Width, $Height)
GUISetState(@SW_SHOW,$hwnd)
_GDIPlus_Startup()
Global $hGraphics = _GDIPlus_GraphicsCreateFromHWND($hwnd)
;---------------------------------------------------------------------------
;Get frame
DllCall($_escapi_Dll,"none:cdecl","doCapture", "int", $device)
Do
$return = DllCall($_escapi_Dll,"int:cdecl","isCaptureDone", "int", $device)
sleep(100)
Until $return[0] = 1
;---------------------------------------------------------------------------
;Display frame
$hBMP = _WinAPI_CreateBitmap($Width, $Height , 1 , 32 , $pTargetBuf)
Local $hImage = _GDIPlus_BitmapCreateFromHBITMAP($hBMP)
_GDIPlus_GraphicsDrawImageRect($hGraphics, $hImage, 0, 0, $Width, $Height)
_GDIPlus_BitmapDispose($hImage)
     _WinAPI_DeleteObject($hBMP)
While 1
Local $msg = GUIGetMsg()
If $msg = $GUI_EVENT_CLOSE Then ExitLoop
sleep(50)
WEnd
;--------------------------------------------------------------------------
;Clean up
$return = DllCall($_escapi_Dll,"none:cdecl","deinitCapture", "int", $device)
DllClose($_escapi_Dll)
_GDIPlus_GraphicsDispose($hGraphics)
_GDIPlus_Shutdown()
GUIDelete($hwnd)

Edited May 4, 2013 by mylise

[wakillon]

Thanks for functions examples

[MadaraUchiha]

Yo, sorry for Grave digging the thread, but I am really interessted in this.

I have problems with the SnapShot function.

I like the snapshotfunction to have the device ID as prameter... but it won't work... why?

Here is my code:

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;--------------------------------------------------------------------------
; ESCAPI is a very simple DLL interface to use video capture devices
; (most commonly webcams, but also video in devices and other similar things)
; Get dll from --> [url="http://sol.gfxile.net/escapi/index.html"]http://sol.gfxile.net/escapi/index.html[/url]
; http://www.autoitscript.com/forum/topic/150536-simple-webcam-access-using-escapi/


#include <GDIplus.au3>
#Include <GUIConstantsEx.au3>


; ================================= DIRECTSHOW VARIABLES ==================================
Local $Width = 640 ;Escapi seems to use 640x480 (or lower) as webcam resolution and will
Local $Height = 480  ; adjust the image size to $Width by $Height
Local $tagSimpleCapParams = "ptr mTargetBuf;" & "int mWidth;" & "int mHeight;"
Local $tSimpleCapParams = DllStructCreate($tagSimpleCapParams)
Local $tTargetBuf = DllStructCreate("BYTE[" & $Width*$Height*4 & "]")
Global $pTargetBuf = DllStructGetPtr($tTargetBuf)
DllStructSetData($tSimpleCapParams, 1, $pTargetBuf)
DllStructSetData($tSimpleCapParams, 2, $Width)
DllStructSetData($tSimpleCapParams, 3, $Height)
Local $pSimpleCapParams = DllStructGetPtr($tSimpleCapParams)
Local $CountCams ; Count connected webcam devices
Local $device = 0 ;change this number to select dshow device
Local $sver = "--ERROR--"
Local $tCam = DllStructCreate("CHAR v[20]") ;buffer used to get ESCAPI device name
DllStructSetData($tCam, 1, $sver)
Local $pCam = DllStructGetPtr($tCam)
local $_escapi_Dll = DllOpen("escapi.dll")
Local $CamInfo
;==========================================================================================

Global $hwnd = GUICreate("Webcam Manager", $Width, $Height)
GUISetState(@SW_SHOW,$hwnd)
_GDIPlus_Startup()
Global $hGraphics = _GDIPlus_GraphicsCreateFromHWND($hwnd)

;==========================================================================================

Func GetDLLVersion()
    $return = DllCall($_escapi_Dll,"int","initCOM")
    $return = DllCall($_escapi_Dll,"int","ESCAPIDLLVersion")
    $CamInfo &= "Dll version = " & Hex($return[0],3) & @CRLF
    Return $CamInfo
EndFunc

Func CountWebcams()
    $return = DllCall($_escapi_Dll,"int","initCOM")
    $return = DllCall($_escapi_Dll,"int","countCaptureDevices")
    $CamInfo &= $return[0] & @CRLF
    Return $CamInfo
EndFunc


Func GetWebcamName($DevNo)
    $return = DllCall($_escapi_Dll,"int","initCOM")
    DllCall($_escapi_Dll,"none:cdecl","getCaptureDeviceName", "uint" , $DevNo, "ptr" , $pCam  , "int" , 20)
    Local $vCam = DllStructGetData($tCam , 1)
    $CamInfo = $vCam & @CRLF
    Return $CamInfo
EndFunc

If CountWebcams() > 0 Then
    For $DevNo = 0 to CountWebcams() -1
        MsgBox(0,'Number ' & $DevNo,GetWebcamName($DevNo))
    Next
EndIf

Snapshot(1)

Func Snapshot($Index)
    DllCall($_escapi_Dll,"none:cdecl","doCapture", "int", $Index)
Do
$return = DllCall($_escapi_Dll,"int:cdecl","isCaptureDone", "int", $Index)
sleep(100)
Until $return[0] = 1
EndFunc
;Display frame
$hBMP = _WinAPI_CreateBitmap($Width, $Height , 1 , 32 , $pTargetBuf)
Local $hImage = _GDIPlus_BitmapCreateFromHBITMAP($hBMP)
_GDIPlus_GraphicsDrawImageRect($hGraphics, $hImage, 0, 0, $Width, $Height)
_GDIPlus_BitmapDispose($hImage)
     _WinAPI_DeleteObject($hBMP)
While 1
Local $msg = GUIGetMsg()
If $msg = $GUI_EVENT_CLOSE Then ExitLoop
sleep(50)
WEnd

;Clean up
$return = DllCall($_escapi_Dll,"none:cdecl","deinitCapture", "int", $device)
DllClose($_escapi_Dll)
_GDIPlus_GraphicsDispose($hGraphics)
_GDIPlus_Shutdown()
GUIDelete($hwnd)

[Werty]

Thanks for this

I'm finally getting full 30fps from my webcam no matter the lighting, it updates fast without waiting for auto white balance to settle, so much smoother than avicap.

Word of warning though, be sure to keep a SLEEP() in there somethere, as without the webcam becomes very hot, I only noticed as I'm using a webcam module salvaged from an old laptop, and converted it into an external usb cam, so just hold the module in my hand, and it burned hot without a SLEEP(), but with a small Sleep(10) it ran cool again.