| Martin Chrzan |
Dec 23rd, 2006 9:04 AM |
Delphi and webcamera catching pictures
Hello! For my program I want to download pictures from webcam.I work in Delphi 7 and I(dont know where) red about unit AVICAP32.dll whitch contain this function. So I tried create simple program which by step show 100 pictures from webcam after I click button:
:
unit Main2;
interface
{-----------------------------------------------------------------------------}
uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms,
Dialogs, ExtCtrls, StdCtrls;
{-----------------------------------------------------------------------------}
const
WM_USER = 1024;
WM_CAP_DRIVER_CONNECT = 1034;
WM_CAP_DRIVER_DISCONNECT = 1035;
WM_CAP_GET_FRAME = 1084;
WM_CAP_COPY = 1054;
WM_CAP_START = WM_USER;
WM_CAP_DLG_VIDEOFORMAT = WM_CAP_START + 41;
WM_CAP_DLG_VIDEOSOURCE = WM_CAP_START + 42;
WM_CAP_DLG_VIDEODISPLAY = WM_CAP_START + 43;
WM_CAP_GET_VIDEOFORMAT = WM_CAP_START + 44;
WM_CAP_SET_VIDEOFORMAT = WM_CAP_START + 45;
WM_CAP_DLG_VIDEOCOMPRESSION = WM_CAP_START + 46;
WM_CAP_SET_PREVIEW = WM_CAP_START + 50;
PICWIDTH = 640;
PICHEIGHT = 480;
{-----------------------------------------------------------------------------}
type
TfmMain = class(TForm)
Panel1 : TPanel;
Button2 : TButton;
procedure FormDestroy (Sender: TObject);
procedure FormCreate (Sender: TObject);
procedure Button2Click (Sender: TObject);
private
FCapHandle : THandle;
public
end;
{*****************************************************************************}
var
fmMain: TfmMain;
{*****************************************************************************}
implementation
{$R *.dfm}
{-----------------------------------------------------------------------------}
function capCreateCaptureWindow(lpszWindowName: LPCSTR; dwStyle: DWORD;
x, y, nWidth, nHeight: integer; hwndParent: HWND; nID: integer): HWND; stdcall;
external 'AVICAP32.DLL' name 'capCreateCaptureWindowA';
//------------------------------------------------------------------------------
procedure TfmMain.FormCreate(Sender: TObject);
begin
FCapHandle:= capCreateCaptureWindow('Video', WS_CHILD or WS_VISIBLE, 0, 0, PICWIDTH, PICHEIGHT, panel1.Handle, 1);
SendMessage(FCapHandle, WM_CAP_DRIVER_CONNECT,0,0);
SendMessage(FCapHandle, WM_CAP_DLG_VIDEOSOURCE,0,0);
SendMessage(FCapHandle, WM_CAP_DLG_VIDEOFORMAT,0,0);
end;
{-----------------------------------------------------------------------------}
procedure TfmMain.FormDestroy(Sender: TObject);
begin
SendMessage(FCapHandle,WM_CAP_DRIVER_DISCONNECT, 0, 0);
end;
{-----------------------------------------------------------------------------}
procedure TfmMain.Button2Click(Sender: TObject);
Var i:integer;
begin
For i:=1 to 100 do begin //Only for testing
SendMessage(FCapHandle,WM_CAP_GET_FRAME, 0, 0); end;
end;
end.
Program is running but is it too slow. Per 1 second it show just about 5 pictures. Does is something wrong in my program or is it error of Delphi ? In the aggregate all this system of catching pictures to panel dont conform me. I need just read single pixels in picture and a dont need to show this picture. It will be the best if the picture are saveing to some memory (canvas) – maybe it will be faster...
Thanks for advice |
