i have used base 64 encoder on my canvas.getImageData()
pixel array
i want its base64 encoded string to save the image to file...
i cant use canvas.toDataURL
because it is not supported in webOS
here is my code it does generate a base64 encoded string but the string doesnot generate an image...
EditorAssistant.prototype.encode = function (input) {
this._keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
// public method for encoding
var output = "";
var chr1, chr2, chr3, enc1, enc2, enc3, enc4;
var i = 0;
input = this._utf8_encode(input);
while (i 开发者_如何学编程< input.length) {
chr1 = input.charCodeAt(i++);
chr2 = input.charCodeAt(i++);
chr3 = input.charCodeAt(i++);
enc1 = chr1 >> 2;
enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
enc4 = chr3 & 63;
if (isNaN(chr2)) {
enc3 = enc4 = 64;
} else if (isNaN(chr3)) {
enc4 = 64;
}
output = output +
this._keyStr.charAt(enc1) + this._keyStr.charAt(enc2) +
this._keyStr.charAt(enc3) + this._keyStr.charAt(enc4);
}
return output;
}
EditorAssistant.prototype._utf8_encode =function (string) {
string = string.replace(/\r\n/g,"\n");
var utftext = "";
for (var n = 0; n < string.length; n++) {
var c = string.charCodeAt(n);
if (c < 128) {
utftext += String.fromCharCode(c);
}
else if((c > 127) && (c < 2048)) {
utftext += String.fromCharCode((c >> 6) | 192);
utftext += String.fromCharCode((c & 63) | 128);
}
else {
utftext += String.fromCharCode((c >> 12) | 224);
utftext += String.fromCharCode(((c >> 6) & 63) | 128);
utftext += String.fromCharCode((c & 63) | 128);
}
}
return utftext;
}
here i am calling above function
var imaged = this.canvasContext.getImageData(0, 0, this.canvas.width, this.canvas.height);
var data ="";
for(var i = 0; i<imaged.data.length; i++){
data += imaged.data[i];
}
var strEncoded = this.encode(data);
$('image').src = 'data:image/jpeg;base64,'+strEncoded;
can u tell me where i am doing wrong ?? thnks
$.getImageData({
url: "http://farm4.static.flickr.com/3002/2758349058_ab6dc9cfdc_z.jpg?zz=1",
success: function(image){
// Set up the canvas
var can = document.getElementsByTagName('canvas')[0];
var ctx = can.getContext('2d');
// Set the canvas width and heigh to the same as the image
$(can).attr('width', image.width);
$(can).attr('height', image.height);
// Draw the image on to the canvas
ctx.drawImage(image, 0, 0, image.width, image.height);
// Get the image data
var image_data = ctx.getImageData(0, 0, image.width, image.height);
var image_data_array = image_data.data;
// Write the image data to the canvas
ctx.putImageData(image_data, 0, 0);
},
error: function(xhr, text_status){
// Handle your error here
}
});
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