打印 POS/ESC Apex3 图像 S.O.S

Question

我有一个 Apex3，我可以毫无问题地关注大部分 the documentation，但是当涉及到图像时，事情变得非常奇怪（缺乏示例 + 操作方法缺乏一致性）。

首先，我尝试使用 JPEG 和 0 质量压缩的 Bitmap byte[] 数组，因为我不介意，使用以下命令：

ESC V n1 n2 数据

结果并不好。

然后我发现有一个用于 apex3 的 android 库，它接受位图并假设打印它，但它不能只打印像这样的奇怪符号：

我尝试使用 JD gui 解码 jar 源，他们似乎对位图字节做了一些工作，这是他们的代码（像 addToDoc(m_Document, ESC + "B") 这样的建议代码；只需将代码放入a ByteArrayOutputStream 数据），（反编译source from here）：

public void writeImage(Bitmap imageObject, int printHeadWidth)
    throws IllegalArgumentException
  {
    if (imageObject == null) {
      throw new IllegalArgumentException("Parameter 'imageObject' was null.");
    }
    if (printHeadWidth < 1) {
      throw new IllegalArgumentException("Parameter 'printHeadWidth' must be greater than 0.");
    }
    int height = imageObject.getHeight();
    int width = imageObject.getWidth();
    

    byte blanklineCount = 0;
    byte[] dataline = new byte[printHeadWidth + 7 >> 3];
    int[] imageData = new int[height * width];
    
    imageObject.getPixels(imageData, 0, width, 0, 0, width, height);
    

    addToDoc(m_Document, ESC + "B");
    for (int row = 0; row < height; row++)
    {
      boolean blankLine = true;
      for (int index = 0; index < width; index += 8)
      {
        byte currentByte = 0;
        int offset = row * width + index;
        if (index >= printHeadWidth) {
          break;
        }
        int value = index + 0 < width ? imageData[(offset + 0)] & 0xFFFFFF : 16777215;
        boolean set = (value >> 0 & 0xFF) + (value >> 8 & 0xFF) + (value >> 16 & 0xFF) < 384;
        currentByte = (byte)(currentByte | (set ? -128 : 0));
        
        value = index + 1 < width ? imageData[(offset + 1)] & 0xFFFFFF : 16777215;
        set = (value >> 0 & 0xFF) + (value >> 8 & 0xFF) + (value >> 16 & 0xFF) < 384;
        currentByte = (byte)(currentByte | (set ? 64 : 0));
        
        value = index + 2 < width ? imageData[(offset + 2)] & 0xFFFFFF : 16777215;
        set = (value >> 0 & 0xFF) + (value >> 8 & 0xFF) + (value >> 16 & 0xFF) < 384;
        currentByte = (byte)(currentByte | (set ? 32 : 0));
        
        value = index + 3 < width ? imageData[(offset + 3)] & 0xFFFFFF : 16777215;
        set = (value >> 0 & 0xFF) + (value >> 8 & 0xFF) + (value >> 16 & 0xFF) < 384;
        currentByte = (byte)(currentByte | (set ? 16 : 0));
        
        value = index + 4 < width ? imageData[(offset + 4)] & 0xFFFFFF : 16777215;
        set = (value >> 0 & 0xFF) + (value >> 8 & 0xFF) + (value >> 16 & 0xFF) < 384;
        currentByte = (byte)(currentByte | (set ? 8 : 0));
        
        value = index + 5 < width ? imageData[(offset + 5)] & 0xFFFFFF : 16777215;
        set = (value >> 0 & 0xFF) + (value >> 8 & 0xFF) + (value >> 16 & 0xFF) < 384;
        currentByte = (byte)(currentByte | (set ? 4 : 0));
        
        value = index + 6 < width ? imageData[(offset + 6)] & 0xFFFFFF : 16777215;
        set = (value >> 0 & 0xFF) + (value >> 8 & 0xFF) + (value >> 16 & 0xFF) < 384;
        currentByte = (byte)(currentByte | (set ? 2 : 0));
        
        value = index + 7 < width ? imageData[(offset + 7)] & 0xFFFFFF : 16777215;
        set = (value >> 0 & 0xFF) + (value >> 8 & 0xFF) + (value >> 16 & 0xFF) < 384;
        currentByte = (byte)(currentByte | (set ? 1 : 0));
        

        dataline[(index >> 3)] = currentByte;
        blankLine &= currentByte == 0;
      }
      if (!blankLine)
      {
        if (blanklineCount > 0)
        {
          addToDoc(m_Document, "A");
          addToDoc(m_Document, blanklineCount);
          blanklineCount = 0;
        }
        addToDoc(m_Document, compressGraphicLine(dataline));
      }
      else
      {
        blanklineCount = (byte)(blanklineCount + 1);
        if (blanklineCount == 255)
        {
          addToDoc(m_Document, "A");
          addToDoc(m_Document, blanklineCount);
          blanklineCount = 0;
        }
      }
    }
    if (blanklineCount > 0)
    {
      addToDoc(m_Document, "A");
      addToDoc(m_Document, blanklineCount);
      blanklineCount = 0;
    }
    addToDoc(m_Document, ESC + "E");
  }
  
  private byte[] compressGraphicLine(byte[] dataline)
  {
    byte count = 0;
    byte currentByte = 0;
    ByteArrayOutputStream rleString = new ByteArrayOutputStream(128);
    

    addToDoc(rleString, "G");
    for (int index = 0; index < dataline.length; index++) {
      if (count == 0)
      {
        currentByte = dataline[index];
        addToDoc(rleString, currentByte);
        count = (byte)(count + 1);
      }
      else if ((count < 255) && (currentByte == dataline[index]))
      {
        count = (byte)(count + 1);
      }
      else
      {
        addToDoc(rleString, count);
        count = 0;
        

        currentByte = dataline[index];
        addToDoc(rleString, currentByte);
        count = (byte)(count + 1);
      }
    }
    if (count > 0) {
      addToDoc(rleString, count);
    }
    if (rleString.size() > dataline.length + 1)
    {
      rleString.reset();
      addToDoc(rleString, "U");
      for (int item = 0; item < dataline.length; item++) {
        addToDoc(rleString, dataline[item]);
      }
    }
    return rleString.toByteArray();
  }

但我不明白为什么它不起作用。

最后，我尝试使用 How can I print an image on a Bluetooth printer in Android? 与指南相同的算法，但仍然打印随机的奇怪符号。

Answer 1

与其浪费时间反编译一些 apk，何不看看官方的 SDK？在制造商网页Downloads & Drivers 上，有一个指向Java SDK 的链接，其中包括源Sample.java。在源代码中创建了一个BufferedImage，所以我想（我没有这样的打印机）这将为您提供解决问题的入口点。他们很可能在同一页面上提供了 Android 演示的源代码Printer Demo Source code for Android

编辑好的。让我们总结一下：您有一张图像并且想要打印它。在示例 Sample.java 中涵盖了这种情况

  BufferedImage newImage = new BufferedImage(1024, 512, BufferedImage.TYPE_4BYTE_ABGR);
  // some lines and rectangles are drawn in the image
  ...
  // the image is printed, following the SDK javadoc for DocumentLP.writeImage
  // "This will cause the image specified to be printed. Images will be expanded to occupy
  // the entire width of the printer, so the correct current width of the printer must be
  // specified. Images that are too wide will be cropped, and images that are too narrow 
  // will be padded on the right."
  testDoc.writeImage(newImage, m_PrinterWidth);

对我来说，你唯一要做的事情：

• 创建一个 BufferedImage 对象
• 将图像从文件中绘制到缓冲图像中
• 调用 DocumentLP 对象的 writeImage 方法

编辑2伪代码sn-p

// taken from SDK javadoc
DocumentLP docLP;
docLP = new DocumentLP("$");

// own code
BufferedInputStream bis = new BufferedInputStream(--from your image--);
BufferedImage bufImage = ImageIO.read(bis);

// have a look into Sample.java for the expected value of m_PrinterWidth
testDoc.writeImage(bufImage, m_PrinterWidth);

edit 3 代码 sn-p for Android（取自随datamax o´neil Android SDK 提供的 DO_AndroidSDKDemo_MainActivity.java

File file = new File(selectedPath);
byte[] readBuffer = new byte[(int)file.length()];
InputStream inputStream= new BufferedInputStream(new FileInputStream(file));
inputStream.read(readBuffer);
inputStream.close();
fileData = readBuffer;

Bitmap m_imageObject = BitmapFactory.decodeByteArray(fileData, 0, fileData.length);
documentLP.clear();
ocumentLP.writeImage(m_imageObject, m_printHeadWidth);