| 1 |
- (function(a){"use strict";var b=function(a,c,d){var e=document.createElement("img"),f,g;return e.onerror=c,e.onload=function(){g&&(!d||!d.noRevoke)&&b.revokeObjectURL(g),c(b.scale(e,d))},window.Blob&&a instanceof Blob||window.File&&a instanceof File?(f=g=b.createObjectURL(a),e._type=a.type):f=a,f?(e.src=f,e):b.readFile(a,function(a){e.src=a})},c=window.createObjectURL&&window||window.URL&&URL.revokeObjectURL&&URL||window.webkitURL&&webkitURL;b.detectSubsampling=function(a){var b=a.width,c=a.height,d,e;return b*c>1048576?(d=document.createElement("canvas"),d.width=d.height=1,e=d.getContext("2d"),e.drawImage(a,-b+1,0),e.getImageData(0,0,1,1).data[3]===0):!1},b.detectVerticalSquash=function(a,b){var c=document.createElement("canvas"),d=c.getContext("2d"),e,f,g,h,i;c.width=1,c.height=b,d.drawImage(a,0,0),e=d.getImageData(0,0,1,b).data,f=0,g=b,h=b;while(h>f)i=e[(h-1)*4+3],i===0?g=h:f=h,h=g+f>>1;return h/b},b.renderImageToCanvas=function(a,c,d,e){var f=a.width,g=a.height,h=c.getContext("2d"),i,j=1024,k=document.createElement("canvas"),l,m,n,o,p;h.save(),b.detectSubsampling(a)&&(f/=2,g/=2),i=b.detectVerticalSquash(a,g),k.width=k.height=j,l=k.getContext("2d"),m=0;while(m<g){n=m+j>g?g-m:j,o=0;while(o<f)p=o+j>f?f-o:j,l.clearRect(0,0,j,j),l.drawImage(a,-o,-m),h.drawImage(k,0,0,p,n,Math.floor(o*d/f),Math.floor(m*e/g/i),Math.ceil(p*d/f),Math.ceil(n*e/g/i)),o+=j;m+=j}h.restore(),k=l=null},b.scale=function(a,c){c=c||{};var d=document.createElement("canvas"),e=a.width,f=a.height,g=Math.max((c.minWidth||e)/e,(c.minHeight||f)/f);return g>1&&(e=parseInt(e*g,10),f=parseInt(f*g,10)),g=Math.min((c.maxWidth||e)/e,(c.maxHeight||f)/f),g<1&&(e=parseInt(e*g,10),f=parseInt(f*g,10)),a.getContext||c.canvas&&d.getContext?(d.width=e,d.height=f,a._type==="image/jpeg"?b.renderImageToCanvas(a,d,e,f):d.getContext("2d").drawImage(a,0,0,e,f),d):(a.width=e,a.height=f,a)},b.createObjectURL=function(a){return c?c.createObjectURL(a):!1},b.revokeObjectURL=function(a){return c?c.revokeObjectURL(a):!1},b.readFile=function(a,b){if(window.FileReader&&FileReader.prototype.readAsDataURL){var c=new FileReader;return c.onload=function(a){b(a.target.result)},c.readAsDataURL(a),c}return!1},typeof define=="function"&&define.amd?define(function(){return b}):a.loadImage=b})(this);
|
