如何通过
JavaScript从上传的图像中剥离EXIF数据？我目前可以使用
this exif-js plugin访问EXIF数据,像这样：
EXIF.getData(oimg,function() {
var orientation = EXIF.getTag(this,"Orientation");
});
但是,我没有找到任何方法来实际删除Exif数据,只能检索它.
更具体地说,我正在努力去摆脱在某些浏览器上旋转图像的Exif数据.
解决方法
>查看
file format和
exif format
> read the file进 arraybuffer
> find所需数据和 remove it
>从剩余的数据创建一个 blob
> upload它与 ajax
> read the file进 arraybuffer
> find所需数据和 remove it
>从剩余的数据创建一个 blob
> upload它与 ajax
这是一个小的演示,选择一个图像与方向数据,看看它的外观与它(仅现代浏览器).
http://jsfiddle.net/mowglisanu/frhwm2xe/3/
<input id="erd" type="file"/>
var input = document.querySelector('#erd');
input.addEventListener('change',load);
function load(){
var fr = new FileReader();
fr.onload = process;
fr.readAsArrayBuffer(this.files[0]);
window.open(URL.createObjectURL(this.files[0]),"_blank","toolbar=yes,scrollbars=yes,resizable=yes,top=500,left=500,width=400,height=400");
}
function process(){
var dv = new DataView(this.result);
var offset = 0,recess = 0;
var pieces = [];
var i = 0;
if (dv.getUint16(offset) == 0xffd8){
offset += 2;
var app1 = dv.getUint16(offset);
offset += 2;
while (offset < dv.byteLength){
console.log(offset,'0x'+app1.toString(16),recess);
if (app1 == 0xffe1){
pieces[i] = {recess:recess,offset:offset-2};
recess = offset + dv.getUint16(offset);
i++;
}
else if (app1 == 0xffda){
break;
}
offset += dv.getUint16(offset);
var app1 = dv.getUint16(offset);
offset += 2;
}
if (pieces.length > 0){
var newPieces = [];
pieces.forEach(function(v){
newPieces.push(this.result.slice(v.recess,v.offset));
},this);
newPieces.push(this.result.slice(recess));
var br = new Blob(newPieces,{type: 'image/jpeg'});
window.open(URL.createObjectURL(br),height=400");
}
}
}
