Does your computer have a camera? Will you think about how to achieve it when you see others playing with QQ?
Here we introduce that using DELPHI to use MS AVICAP32.DLL to easily implement camera programming.
If you add your network programming level, implementing a video chat will not be a problem.
Check out the code below:
const WM_CAP_START = WM_USER;
const WM_CAP_STOP = WM_CAP_START + 68;
const WM_CAP_DRIVER_CONNECT = WM_CAP_START + 10;
const WM_CAP_DRIVER_DISCONNECT = WM_CAP_START + 11;
const WM_CAP_SAVEDIB = WM_CAP_START + 25;
const WM_CAP_GRAB_FRAME = WM_CAP_START + 60;
const WM_CAP_SEQUENCE = WM_CAP_START + 62;
const WM_CAP_FILE_SET_CAPTURE_FILEA = WM_CAP_START + 20;
const WM_CAP_SEQUENCE_NOFILE =WM_CAP_START+ 63
const WM_CAP_SET_OVERLAY =WM_CAP_START+ 51
const WM_CAP_SET_PREVIEW =WM_CAP_START+ 50
const WM_CAP_SET_CALLBACK_VIDEOSTREAM = WM_CAP_START +6;
const WM_CAP_SET_CALLBACK_ERROR=WM_CAP_START +2;
const WM_CAP_SET_CALLBACK_STATUSA= WM_CAP_START +3;
const WM_CAP_SET_CALLBACK_FRAME= WM_CAP_START +5;
const WM_CAP_SET_SCALE=WM_CAP_START+ 53
const WM_CAP_SET_PREVIEWRATE=WM_CAP_START+ 52
function capCreateCaptureWindowA(lpszWindowName: PCHAR; dwStyle: longint; x: integer;
y : integer;nWidth : integer;nHeight : integer;ParentWin : HWND;
nId : integer): HWND;STDCALL EXTERNAL 'AVICAP32.DLL';
The above code is the definition of a function and constant that we mainly use.
OK, open your Delphi, create a new project, and add the above definition.
Create a new window, put a panel on it, add a button, and set Caption to "Start"
Here you need to define a global variable, var hWndC: THandle;
The code of the start button is as follows:
Begin
hWndC := capCreateCaptureWindowA('My Own Capture Window',WS_CHILD or WS_VISIBLE,Panel1.Left,Panel1.Top,Panel1.Width,Panel1.Height,Form1.Handle,0);
hWndC := capCreateCaptureWindowA('My Own Capture Window',WS_CHILD or WS_VISIBLE,Panel1.Left,Panel1.Top,Panel1.Width,Panel1.Height,Form1.Handle,0);
if hWndC <> 0 then
Begin
SendMessage(hWndC, WM_CAP_SET_CALLBACK_VIDEOSTREAM, 0, 0);
SendMessage(hWndC, WM_CAP_SET_CALLBACK_ERROR, 0, 0);
SendMessage(hWndC, WM_CAP_SET_CALLBACK_STATUSA, 0, 0);
SendMessage(hWndC, WM_CAP_DRIVER_CONNECT, 0, 0);
SendMessage(hWndC, WM_CAP_SET_SCALE, 1, 0);
SendMessage(hWndC, WM_CAP_SET_PREVIEWRATE, 66, 0);
SendMessage(hWndC, WM_CAP_SET_OVERLAY, 1, 0);
SendMessage(hWndC, WM_CAP_SET_PREVIEW, 1, 0);
end;
Press F9 to run it, how about it? Can you see the camera's video screen?
Then how to stop? Add another button caption to "stop"
The code is as follows:
if hWndC <> 0 then begin
SendMessage(hWndC, WM_CAP_DRIVER_DISCONNECT, 0, 0);
hWndC := 0;
end;
The video screen was screened, how can I save it?
The following is saved in two ways, one is the BMP static diagram and the other is the AVI animation.
Put three buttons on the form, and set the caption to "Save BMP", "Start Video Recording", and "Stop Video Recording" respectively.
The codes of the three buttons are as follows:
//Save BMP
if hWndC <> 0 then begin
SendMessage(hWndC,WM_CAP_SAVEDIB,0,longint(pchar('c://test.bmp')));
end;
//Start video recording
if hWndC <> 0 then
Begin
SendMessage(hWndC,WM_CAP_FILE_SET_CAPTURE_FILEA,0, Longint(pchar('c://test.avi')));
SendMessage(hWndC, WM_CAP_SEQUENCE, 0, 0);
end;
//Stop recording
if hWndC <> 0 then begin
SendMessage(hWndC, WM_CAP_STOP, 0, 0);
end;
Run it again and have a look. . You can save a few pictures to see, or you can record them into AVI and enjoy them slowly.
Program running effect: [Related maps]
The complete program code is as follows:
unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls, ExtCtrls;
type
TForm1 = class(TForm)
Panel1: TPanel;
Button1: TButton;
Button2: TButton;
Button3: TButton;
Button4: TButton;
Button5: TButton;
procedure Button1Click(Sender: TObject);
procedure Button2Click(Sender: TObject);
procedure Button3Click(Sender: TObject);
procedure Button4Click(Sender: TObject);
procedure Button5Click(Sender: TObject);
procedure FormClose(Sender: TObject; var Action: TCloseAction);
Private
hWndC : THandle;
public
{ Public declarations }
end;
var
Form1: TForm1;
const WM_CAP_START = WM_USER;
const WM_CAP_STOP = WM_CAP_START + 68;
const WM_CAP_DRIVER_CONNECT = WM_CAP_START + 10;
const WM_CAP_DRIVER_DISCONNECT = WM_CAP_START + 11;
const WM_CAP_SAVEDIB = WM_CAP_START + 25;
const WM_CAP_GRAB_FRAME = WM_CAP_START + 60;
const WM_CAP_SEQUENCE = WM_CAP_START + 62;
const WM_CAP_FILE_SET_CAPTURE_FILEA = WM_CAP_START + 20;
const WM_CAP_SEQUENCE_NOFILE =WM_CAP_START+ 63
const WM_CAP_SET_OVERLAY =WM_CAP_START+ 51
const WM_CAP_SET_PREVIEW =WM_CAP_START+ 50
const WM_CAP_SET_CALLBACK_VIDEOSTREAM = WM_CAP_START +6;
const WM_CAP_SET_CALLBACK_ERROR=WM_CAP_START +2;
const WM_CAP_SET_CALLBACK_STATUSA= WM_CAP_START +3;
const WM_CAP_SET_CALLBACK_FRAME= WM_CAP_START +5;
const WM_CAP_SET_SCALE=WM_CAP_START+ 53
const WM_CAP_SET_PREVIEWRATE=WM_CAP_START+ 52
function capCreateCaptureWindowA(lpszWindowName: PCHAR;
dwStyle : longint;x : integer;y : integer;nWidth : integer;
nHeight : integer;ParentWin : HWND;nId : integer): HWND;
STDCALL EXTERNAL 'AVICAP32.DLL';
Implementation
{$R *.dfm}
procedure TForm1.Button1Click(Sender: TObject);
Begin
hWndC := capCreateCaptureWindowA('My Own Capture Window',WS_CHILD or WS_VISIBLE,Panel1.Left,Panel1.Top,Panel1.Width,Panel1.Height,Form1.Handle,0);
hWndC := capCreateCaptureWindowA('My Own Capture Window',WS_CHILD or WS_VISIBLE,Panel1.Left,Panel1.Top,Panel1.Width,Panel1.Height,Form1.Handle,0);
if hWndC <> 0 then
Begin
SendMessage(hWndC, WM_CAP_SET_CALLBACK_VIDEOSTREAM, 0, 0);
SendMessage(hWndC, WM_CAP_SET_CALLBACK_ERROR, 0, 0);
SendMessage(hWndC, WM_CAP_SET_CALLBACK_STATUSA, 0, 0);
SendMessage(hWndC, WM_CAP_DRIVER_CONNECT, 0, 0);
SendMessage(hWndC, WM_CAP_SET_SCALE, 1, 0);
SendMessage(hWndC, WM_CAP_SET_PREVIEWRATE, 66, 0);
SendMessage(hWndC, WM_CAP_SET_OVERLAY, 1, 0);
SendMessage(hWndC, WM_CAP_SET_PREVIEW, 1, 0);
end;
end;
procedure TForm1.Button2Click(Sender: TObject);
Begin
if hWndC <> 0 then begin
SendMessage(hWndC, WM_CAP_DRIVER_DISCONNECT, 0, 0);
hWndC := 0;
end;
end;
procedure TForm1.Button3Click(Sender: TObject);
Begin
if hWndC <> 0 then begin
SendMessage(hWndC,WM_CAP_SAVEDIB,0,longint(pchar('c://test.bmp')));
end;
end;
procedure TForm1.Button4Click(Sender: TObject);
Begin
if hWndC <> 0 then
Begin
SendMessage(hWndC,WM_CAP_FILE_SET_CAPTURE_FILEA,0, Longint(pchar('c://test.avi')));
SendMessage(hWndC, WM_CAP_SEQUENCE, 0, 0);
end;
end;
procedure TForm1.Button5Click(Sender: TObject);
Begin
if hWndC <> 0 then begin
SendMessage(hWndC, WM_CAP_STOP, 0, 0);
end;
end;
procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
Begin
if hWndC <> 0 then begin
SendMessage(hWndC, WM_CAP_DRIVER_DISCONNECT, 0, 0);
end;
end;
end.
If the computer does not have a camera but wants to see the effect of the program, is that OK?
Haha, of course, you can find a virtual camera and just do it. You can try the software SoftCam, which is a veritable software camera.
It can be simulated as a "real" camera. I would like to remind you, don't use this thing to deceive MM or GG on chat software such as QQ, MSN.
Regarding camera programming, you can also take a look at this set of VCL components: DSPack. DSPack is a set of classes and components that use Microsoft Direct Show and DirectX technologies. It is designed and worked on DirectX 9 and supports systems Win9X, ME, 2000 and Windows XP.
Okay, let’s introduce these. As for how to implement video chat, it depends on you. It’s just to compress the data and transmit it to the other party and display it. But then again, it seems simple, but it’s still a bit difficult to implement.