從epson熱敏打印機收到的圖像顯示白色水平線

Question

我已經打印使用delphi7代碼的epson TM-T82打印機的位圖圖像。 我正在向epson打印機發送ESCPOS命令以打印位圖圖像。 此打印的位圖圖像包含徽標中的白線。

當我使用具有相同徽標的Epson打印機實用程序時，它打印得很好。

有沒有人知道如何解決這個問題？

這是我的代碼：

unit ssESCPosPrintBitmap; 

interface 

type 
    // *** ------------------------------------------------------------------------- 
    // *** INTERFACE: IssESCPosPrintBitmap 
    // *** ------------------------------------------------------------------------- 
    IssESCPosPrintBitmap = interface(IInterface) 
    ['{3F279585-6D2E-451F-AF97-76F0E07A70DF}'] 
    function RenderBitmap(const ABitmapFilename: string): string; 
    end; 

    function _ESCPosPrintBitmap(): IssESCPosPrintBitmap; 

implementation 

uses 
    Windows, 
    Graphics, 
    Math; 

type 
    TRGBTripleArray = ARRAY[Word] of TRGBTriple; 
    pRGBTripleArray = ^TRGBTripleArray; // Use a PByteArray for pf8bit color. 

    // *** ------------------------------------------------------------------------- 
    // *** RECORD: TBitmapData 
    // *** ------------------------------------------------------------------------- 
    TBitmapData = record 
    Dots  : array of Boolean; 
    Height : Integer; 
    Width  : Integer; 
    end; 

    // *** ------------------------------------------------------------------------- 
    // *** CLASS: TssESCPosPrintBitmap 
    // *** ------------------------------------------------------------------------- 
    TssESCPosPrintBitmap = class(TInterfacedObject, IssESCPosPrintBitmap) 
    private 
     FLumThreshold : Integer; 
     FBitmap  : TBitmap; 
     FBitmapData : TBitmapData; 
     procedure LoadBitmapData(); 
    public 
     constructor Create(); 
     destructor Destroy; override; 

     function RenderBitmap(const ABitmapFilename: string): string; 
    end; 

const 
    C_DEFAULT_THRESHOLD = 127; 

function _ESCPosPrintBitmap(): IssESCPosPrintBitmap; 
begin 
    Result := TssESCPosPrintBitmap.Create(); 
end; 


{ TssESCPosPrintBitmap } 

{------------------------------------------------------------------------------- 
    Procedure: TssESCPosPrintBitmap.Create 
    Author: bvonfintel 
    DateTime: 2015.01.06 
    Arguments: None 
    Result: None 
-------------------------------------------------------------------------------} 
constructor TssESCPosPrintBitmap.Create; 
begin 
    inherited; 
    FBitmap  := TBitmap.Create(); 
    FLumThreshold := C_DEFAULT_THRESHOLD; 
end; 

procedure TssESCPosPrintBitmap.LoadBitmapData; 
var 
    LIndex : Integer; 
    LX  : Integer; 
    LY  : Integer; 
    LLine : pRGBTripleArray; 
    LPixel : TRGBTriple; 
    LLum : Integer; 
begin 
    LIndex := 0; 
    FBitmapData.Height := FBitmap.Height; 
    FBitmapData.Width := FBitmap.Width; 
    SetLength(FBitmapData.Dots, FBitmap.Width * FBitmap.Height); 

    for LY := 0 to FBitmap.Height-1 do begin 
    LLine := FBitmap.ScanLine[LY]; 

    for LX := 0 to FBitmap.Width-1 do begin 
     LPixel := LLine[LX]; 
     LLum := Trunc((LPixel.rgbtRed * 0.3) + (LPixel.rgbtGreen * 0.59) + (LPixel.rgbtBlue * 0.11)); 

     FBitmapData.Dots[LIndex] := (LLum < FLumThreshold); 

     Inc(LIndex); 
    end; 

    end; 
end; 

function TssESCPosPrintBitmap.RenderBitmap(const ABitmapFilename: string): string; 
var 
    LOffset  : Integer; 
    LX   : Integer; 
    LSlice  : Byte; 
    LB   : Integer; 
    LK   : Integer; 
    LY   : Integer; 
    LI   : Integer; 
    LV   : Boolean; 
    LVI   : Integer; 
begin 
    // *** load the Bitmap from the file 
    FBitmap.LoadFromFile(ABitmapFilename); 
    FBitmap.PixelFormat := pf24bit; 

    // *** Convert the bitmap to an array of B/W pixels 
    LoadBitmapData(); 


    // *** Set the line spacing to 24 dots, the height of each "stripe" of the 
    // *** image that we're drawing 
    Result := #27'3'#24; 

    LOffset := 0; 
    while (LOffset < FBitmapData.Height) do begin 
    Result := Result + #27; 
    Result := Result + '*'; // Bit image mode 
    Result := Result + #33; // 24-dot double density 
    Result := Result + Char(Lo(FBitmapData.Width)); 
    Result := Result + Char(Hi(FBitmapData.Width)); 

    for LX := 0 to FBitmapData.Width -1 do begin 
     for LK := 0 to 2 do begin 
     LSlice := 0; 
     for LB := 0 to 7 do begin 
      LY := (((LOffset div 8) + LK) * 8) + LB; 
      LI := (LY * FBitmapData.Width) + LX; 

      LV := False; 
      if (LI < Length(FBitmapData.Dots)) then 
      LV := FBitmapData.Dots[LI]; 

      LVI := IfThen(LV, 1, 0); 

      LSlice := LSlice or (LVI shl (7 - LB)); 
     end; 

     Result := Result + Chr(LSlice); 
     end; 
    end; 

    LOffset := LOffset + 24; 
    Result := Result + sLineBreak; 
    end; 

    // *** Restore the line spacing to the default of 30 dots 
    Result := Result + #27'3'#30 + sLineBreak + sLineBreak + sLineBreak; 
end; 

Function TfrmEpsonPrint.PrintLabel(EPLCode : String): Boolean; 
var 
    ADevice, ADeviceName, ADevicePort: array[0..255]of Char; 
    PrinterHandle: THandle; 
    DocInfo: TDocInfo1; 
    dwJob: cardinal; 
    dwBytesWritten: cardinal; 
    AUtf8: UTF8string; 
    ADeviceMode: THandle; 
    Index: Integer; 
begin 
    Try 
    Try 
     Result := True; 
     //printer 
     Printer.Refresh; 
     Index := Printer.Printers.IndexOf('EPSON TM-T82 Receipt'); 
     If Index >= 0 Then 
     Printer.PrinterIndex := Index 
     Else 
     Begin 
     ShowMessage('EPSON TM-T82 Receipt Printer not found. Please add Generic/Text Only Printer with name 2824'); 
     Result := False; 
     Exit; 
     End; 
     Printer.GetPrinter(ADevice, ADeviceName, ADevicePort, ADeviceMode); 

     //Need a handle to the printer 
     if not OpenPrinter(ADevice, PrinterHandle, nil) Then 
     Exit; 

     //Fill in the structure with info about this "document" 
     DocInfo.pDocName := PChar('Label.txt'); 
     DocInfo.pOutputFile := nil; 
     DocInfo.pDatatype := 'RAW'; 

     //Inform the spooler the document is beginning 
     dwJob := StartDocPrinter(PrinterHandle, 1, @DocInfo); 
     if dwJob = 0 then 
     begin 
     ClosePrinter(PrinterHandle); 
     PrinterHandle := 0; 
     Exit; 
     end; 

     //Start a page 
     if not StartPagePrinter(PrinterHandle) then 
     begin 
     EndDocPrinter(PrinterHandle); 
     ClosePrinter(PrinterHandle); 
     PrinterHandle := 0; 
     Exit; 
     end; 

     EPLCode := _ESCPosPrintBitmap.RenderBitmap('C:\POS\RecTopImage1.bmp'); 
    // EPLCode := EPLCode + #29'V'#1; 

     //epl code... 
     AUtf8 := UTF8string(EPLCode); 
     WritePrinter(PrinterHandle, @AUtf8[1], Length(AUtf8), dwBytesWritten); 

     //End the page 
     if not EndPagePrinter(PrinterHandle) then 
     begin 
     EndDocPrinter(PrinterHandle); 
     ClosePrinter(PrinterHandle); 
     PrinterHandle := 0; 
     Exit; 
     end; 

     //Inform the spooler that the document is ending 
     if not EndDocPrinter(PrinterHandle) then 
     begin 
     ClosePrinter(PrinterHandle); 
     PrinterHandle := 0; 
     Exit; 
     end; 
     //Tidy up the printer handle 
     ClosePrinter(PrinterHandle); 
     PrinterHandle := 0; 
    Except 
    End; 
    Finally 
    PrinterHandle := 0; 
    End; 
End; 

Answer 1

每一行是24點，爲8行，每行3個點的。但是當你輸出3行時，你已經下降了2個點。嘗試將行距設置爲22點。更換

Result := #27'3'#24; 

與

Result := #27'3'#22; 

（或者，如果不工作，將其設置爲21，我不知道，如果你已經通過2點或3階梯）