Phonegap相機API和條形碼閱讀器關係

我嘗試在Sencha Touch的應用程序中添加條形碼閱讀器。我用過phonegap camera api。我的捕捉代碼在這裏：Phonegap相機API和條形碼閱讀器關係

navigator.camera.getPicture(onSuccess, onFail, { quality: 50, 
    destinationType: Camera.DestinationType.FILE_URI,saveToPhotoAlbum : true 
}); 

function onSuccess(imageData) { 

    try 
    { 

var barcode =getBarcodeFromImage(imageData); 
    alert('The scanned barcode is: ' + barcode); 
    } 
    catch(error) 
    { 
     alert(error); 
    } 

} 

function onFail(message) { 
    alert('Failed because: ' + message); 
}

我可以打開相機拍照。它工作。但我想在這張照片中閱讀條形碼。

它我的條形碼閱讀器的代碼：

(function(){ 
    var UPC_SET = { 
     "3211": '0', 
     "2221": '1', 
     "2122": '2', 
     "1411": '3', 
     "1132": '4', 
     "1231": '5', 
     "1114": '6', 
     "1312": '7', 
     "1213": '8', 
     "3112": '9' 
    }; 

    getBarcodeFromImage = function(imgOrId){ 
alert('girdi'); 

     var doc = document, 

    img = "object" == typeof imgOrId ? imgOrId : doc.getElementById(imgOrId), 
      canvas = doc.createElement("canvas"), 
      ctx = canvas.getContext("2d"), 
      width = img.width, 
      height = img.height, 
      spoints = [1, 9, 2, 8, 3, 7, 4, 6, 5], 
      numLines = spoints.length, 
      slineStep = height/(numLines + 1); 
     canvas.width = width; 
     canvas.height = height; 
     ctx.drawImage(img, 0, 0); 

     while(numLines--){ 
      console.log(spoints[numLines]); 
      var pxLine = ctx.getImageData(0, slineStep * spoints[numLines], width, 2).data, 
       sum = [], 
       min = 0, 
       max = 0; 
      for(var row = 0; row < 2; row++){ 
       for(var col = 0; col < width; col++){ 
        var i = ((row * width) + col) * 4, 
         g = ((pxLine[i] * 3) + (pxLine[i + 1] * 4) + (pxLine[i + 2] * 2))/9, 
         s = sum[col]; 
        pxLine[i] = pxLine[i + 1] = pxLine[i + 2] = g; 
        sum[col] = g + (undefined == s ? 0 : s); 
       } 
      } 
      for(var i = 0; i < width; i++){ 
       var s = sum[i] = sum[i]/2; 
       if(s < min){ min = s; } 
       if(s > max){ max = s; } 
      } 
      var pivot = min + ((max - min)/2), 
       bmp = []; 
      for(var col = 0; col < width; col++){ 
       var matches = 0; 
       for(var row = 0; row < 2; row++){ 
        if(pxLine[((row * width) + col) * 4] > pivot){ matches++; } 
       } 
       bmp.push(matches > 1); 
      } 
      var curr = bmp[0], 
       count = 1, 
       lines = []; 
      for(var col = 0; col < width; col++){ 
       if(bmp[col] == curr){ count++; } 
       else{ 
        lines.push(count); 
        count = 1; 
        curr = bmp[col]; 
       } 
      } 
      var code = '', 
       bar = ~~((lines[1] + lines[2] + lines[3])/3), 
       u = UPC_SET; 
      for(var i = 1, l = lines.length; i < l; i++){ 
       if(code.length < 6){ var group = lines.slice(i * 4, (i * 4) + 4); } 
       else{ var group = lines.slice((i * 4) + 5, (i * 4) + 9); } 
       var digits = [ 
        Math.round(group[0]/bar), 
        Math.round(group[1]/bar), 
        Math.round(group[2]/bar), 
        Math.round(group[3]/bar) 
       ]; 
       code += u[digits.join('')] || u[digits.reverse().join('')] || 'X'; 
       if(12 == code.length){ return code; break; } 
      } 
      if(-1 == code.indexOf('X')){ return code || false; } 
     } 
     return false; 
    } 
})();

當相機拍攝的圖像返回URI。在條碼功能拋出「不能讀空的特性‘寬度’。所以功能不看我拍攝的照片。如何解決這一問題？

來源

2014-01-10 cptc

我用PhoneGap的條形碼API和解決問題

來源

2014-02-14 09:25:27 cptc

Phonegap相機API和條形碼閱讀器關係

回答

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