I get a buffer of data represent an image in Base64.
The data I got (represent image in base64) (part of the data)
193,109,51,74,182,71,212,38,78,62,211,48,81,145,244,39,244,250,215,192,113,46,101,136,203,149,44,6,90,147,197,215,109,66,251,69,47,138,111,202,43,239,122,45,108,125,22,6,149,44,84,103,136,198,74,212,41,171,203,188,187,69,121,183,255,0,7,75,156,191,140,190,45,181,219,141,43,195,214,107,30,129,3,145,38,110,60,135,185,35,130,119,4,108,244,238,0,227,3,140,86,85,237,134,149,241,3,69,158,251,71,134,93,31,88,211,72,82,1,30,100,76,70,65,12,9,12,141,207,94,184,32,140,215,45,47,196,111,130,177,187,34,120,79,197,65,84,224,8,175,93,20,99,176,31,107,24,250,96,85,141,47,227,159,195,111,11,219,223,46,133,225,175,17,91,73,120,170,178,189,196,137,49,96,185,218,50,247,44,64,27,155,167,173,123,252,61,144,97,242,8,63,102,156,234,207,227,169,43,115,77,245,230,119,122,111,104,173,23,78,167,204,103,121,165,108,217,46,88,184,40,124.....
Successfully decode.
Now I'm trying to add the image to my canvas without success as following:
function fillCanvasImage(x, y, width, height, image, pageID) {
if (image == )
return;
var canvas = document.getElementById(AppPmainCanvas + pageID);
if (canvas && canvas.getContext) {
var context = canvas.getContext('2d');
if (context) {
context.clearRect(0, 0, canvas.width, canvas.height);
var img = new Image();
img.src = base64_decode(image);
//img.onload = function () {
context.drawImage(img, 0, 0, canvas.width, canvas.height);
//}
}
}
}
I'm convert the data form base64 by:
function base64_decode(data) {
var b64 = ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=;
var o1, o2, o3, h1, h2, h3, h4, bits, i = 0,
ac = 0,
dec = ,
tmp_arr = [];
if (!data) {
return data;
}
data += '';
do { // unpack four hexets into three octets using index points in b64
h1 = b64.indexOf(data.charAt(i++));
h2 = b64.indexOf(data.charAt(i++));
h3 = b64.indexOf(data.charAt(i++));
h4 = b64.indexOf(data.charAt(i++));
bits = h1 << 18 | h2 << 12 | h3 << 6 | h4;
o1 = bits >> 16 & 0xff;
o2 = bits >> 8 & 0xff;
o3 = bits & 0xff;
if (h3 == 64) {
tmp_arr[ac++] = String.fromCharCode(o1);
} else if (h4 == 64) {
tmp_arr[ac++] = String.fromCharCode(o1, o2);
} else {
tmp_arr[ac++] = String.fromCharCode(o1, o2, o3);
}
} while (i < data.length);
dec = tmp_arr.join('');
dec = utf8_decode(dec);
return dec;
};
// private method for UTF-8 decoding
function utf8_decode(utftext) {
var string = ;
var i = 0;
var c = 0,
c1 = 0,
c2 = 0;
while (i < utftext.length) {
c = utftext.charCodeAt(i);
if (c < 128) {
string += String.fromCharCode(c);
i++;
} else if ((c > 191) && (c < 224)) {
c1 = utftext.charCodeAt(i + 1);
string += String.fromCharCode(((c & 31) << 6) | (c1 & 63));
i += 2;
} else {
c1 = utftext.charCodeAt(i + 1);
c2 = utftext.charCodeAt(i + 2);
string += String.fromCharCode(((c & 15) << 12) | ((c1 & 63) << 6) | (c2 & 63));
i += 3;
}
}
return string;
};
It does not work, I do the following:
in my server side I convert the image as following:
public static string BitmapSourceToByteBase64(System.Windows.Media.Imaging.
{
var encoder = new System.Windows.Media.Imaging.JpegBitmapEncoder();
var frame = System.Windows.Media.Imaging.BitmapFrame.Create(source);
encoder.Frames.Add(frame);
var stream = new MemoryStream();
encoder.Save(stream);
return Convert.ToBase64String(stream.ToArray());
//I tired to do return data:image/name_jpg;base64,+Convert.ToBase64String(stream.ToArray());
//But got an exception on serialize base64 div 4 in the web client
}
in my website, I got the data (base64 image) and try to do the following:
context.drawImage(0,0,'data:image/jpeg;base64,'+image);
I also tried:
context.drawImage('data:image/jpeg;base64,'+image,0,0);
NOT WORK!!! any idea?
