DIY個(gè)照相機(jī)-Delphi實(shí)現(xiàn)攝像頭拍照功能

簡介：本文提供一段完整的Delphi代碼，實(shí)現(xiàn)利用攝像頭進(jìn)行拍照的功能。注意需要TVideoCap控件支持。
    procedure Tfrm1.Button2Click(Sender: TObject);
    Var
    jpeg: TJPEGImage;
    bmp: TBitmap;
    MyStm:TMemoryStream;
    strfilename,strcard:String;
    begin
    inherited;
    strfilename:=extractfilepath(Application.ExeName);
    with DBEdit12.DataSource.DataSet do
    begin
    if not VideoCap1.SaveAsDIB then
    begin
    ShowMessage('拍攝照片失敗');
    Abort;
    end;//
    bmp:= TBitmap.Create;
    try
    bmp.LoadFromFile(strfilename+ 'Capture.bmp' );
    MyStm:=TMemoryStream.Create;
    jpeg:= TJPEGImage.Create;
    try
    jpeg.Assign( bmp );
    jpeg.compress;
    jpeg.SaveTofile( strfilename+'Capture.jpg');
    strfilename:=strfilename+'Capture.jpg';
    jpeg.LoadFromFile(strfilename);
    jpeg.SaveToStream(MyStm);
    MyStm.Position:=0;
    OpenQry(query1,'select count(1) as cnt from tb_photo where card_no='''+strcard+'''');//先查找是否有此卡號(hào)
    OpenQry(pubqry,'select * from tb_photo where card_no='''+strcard+'''');//打開卡號(hào)數(shù)據(jù)表
    {OpenQry是自定義打開數(shù)據(jù)表的函數(shù)
    OpenQry(qry1:TQuery,ssql:String);
    begin
    with qry1 do
    beign
    if active then
    close;
    sql.clear;
    sql.add(ssql);
    try
    open
    catch
    on E: Exception do ErrorDialog(E.Message, E.HelpContext);
    end;//try
    end;
    end;
    }
    with query1 do
    begin
    if pubqry.Fields[0].AsInteger >0 then //先判斷此卡號(hào)的圖片是否存在，若存在，替換；否則，插入。
    Edit
    else
    Insert;
    FieldByName('card_no').AsString :=strcard;
    TBlobField(FieldByName('photo')).LoadFromStream(MyStm);
    Post; //統(tǒng)一提交
    end;//with
    finally
    MyStm.Free;
    jpeg.free;
    end; //try
    finally
    bmp.free;
    end;//try
    end;//with
    end;