dootask/public/js/recorder/frequency.histogram.view.js

/*
录音
https://github.com/xiangyuecn/Recorder
src: extensions/frequency.histogram.view.js
*/
!function(){"use strict";var t=function(t){return new e(t)},d="FrequencyHistogramView",e=function(t){var e=this,r={scale:2,fps:20,lineCount:30,widthRatio:.6,spaceWidth:0,minHeight:0,position:-1,mirrorEnable:!1,stripeEnable:!0,stripeHeight:3,stripeMargin:6,fallDuration:1e3,stripeFallDuration:3500,linear:[0,"rgba(0,187,17,1)",.5,"rgba(255,215,0,1)",1,"rgba(255,102,0,1)"],stripeLinear:null,shadowBlur:0,shadowColor:"#bbb",stripeShadowBlur:-1,stripeShadowColor:"",onDraw:function(t,e){}};for(var a in t)r[a]=t[a];e.set=t=r;var i=t.elem;i&&("string"==typeof i?i=document.querySelector(i):i.length&&(i=i[0])),i&&(t.width=i.offsetWidth,t.height=i.offsetHeight);var o=t.scale,n=t.width*o,l=t.height*o;if(!n||!l)throw new Error(d+"无宽高");var h=e.elem=document.createElement("div"),s=["","transform-origin:0 0;","transform:scale("+1/o+");"];h.innerHTML='<div style="width:'+t.width+"px;height:"+t.height+'px;overflow:hidden"><div style="width:'+n+"px;height:"+l+"px;"+s.join("-webkit-")+s.join("-ms-")+s.join("-moz-")+s.join("")+'"><canvas/></div></div>';var f=e.canvas=h.querySelector("canvas");e.ctx=f.getContext("2d");if(f.width=n,f.height=l,i&&(i.innerHTML="",i.appendChild(h)),!Recorder.LibFFT)throw new Error("需要lib.fft.js支持");e.fft=Recorder.LibFFT(1024),e.lastH=[],e.stripesH=[]};e.prototype=t.prototype={genLinear:function(t,e,r,a){for(var i=t.createLinearGradient(0,r,0,a),o=0;o<e.length;)i.addColorStop(e[o++],e[o++]);return i},input:function(t,e,r){var a=this;a.sampleRate=r,a.pcmData=t,a.pcmPos=0,a.inputTime=Date.now(),a.schedule()},schedule:function(){var t=this,e=t.set,r=Math.floor(1e3/e.fps);t.timer||(t.timer=setInterval(function(){t.schedule()},r));var a=Date.now(),i=t.drawTime||0;if(a-t.inputTime>1.3*e.stripeFallDuration)return clearInterval(t.timer),void(t.timer=0);if(!(a-i<r)){t.drawTime=a;for(var o=t.fft.bufferSize,n=t.pcmData,l=t.pcmPos,h=new Int16Array(o),s=0;s<o&&l<n.length;s++,l++)h[s]=n[l];t.pcmPos=l;var f=t.fft.transform(h);t.draw(f,t.sampleRate)}},draw:function(t,e){var r=this,a=r.set,i=r.ctx,o=a.scale,n=a.width*o,l=a.height*o,h=a.lineCount,s=r.fft.bufferSize,f=a.position,d=Math.abs(a.position),c=1==f?0:l,p=l;d<1&&(c=p/=2,p=Math.floor(p*(1+d)),c=Math.floor(0<f?c*(1-d):c*(1+d)));for(var u=r.lastH,w=r.stripesH,v=Math.ceil(p/(a.fallDuration/(1e3/a.fps))),g=Math.ceil(p/(a.stripeFallDuration/(1e3/a.fps))),m=a.stripeMargin*o,M=1<<(Math.round(Math.log(s)/Math.log(2)+3)<<1),b=Math.log(M)/Math.log(10),L=20*Math.log(32767)/Math.log(10),y=s/2,S=Math.min(y,Math.floor(5e3*y/(e/2))),C=S==y,H=C?h:Math.round(.8*h),R=S/H,D=C?0:(y-S)/(h-H),x=0,F=0;F<h;F++){var T=Math.ceil(x);x+=F<H?R:D;for(var B=Math.min(Math.ceil(x),y),E=0,j=T;j<B;j++)E=Math.max(E,Math.abs(t[j]));var I=M<E?Math.floor(17*(Math.log(E)/Math.log(10)-b)):0,q=p*Math.min(I/L,1);u[F]=(u[F]||0)-v,q<u[F]&&(q=u[F]),q<0&&(q=0),u[F]=q;var z=w[F]||0;if(q&&z<q+m)w[F]=q+m;else{var P=z-g;P<0&&(P=0),w[F]=P}}i.clearRect(0,0,n,l);var W=r.genLinear(i,a.linear,c,c-p),k=a.stripeLinear&&r.genLinear(i,a.stripeLinear,c,c-p)||W,A=r.genLinear(i,a.linear,c,c+p),G=a.stripeLinear&&r.genLinear(i,a.stripeLinear,c,c+p)||A;i.shadowBlur=a.shadowBlur*o,i.shadowColor=a.shadowColor;var V=a.mirrorEnable,J=V?2*h-1:h,K=a.widthRatio,N=a.spaceWidth*o;0!=N&&(K=(n-N*(J+1))/n);for(var O=Math.max(1*o,Math.floor(n*K/J)),Q=(n-J*O)/(J+1),U=a.minHeight*o,X=V?n/2-(Q+O/2):0,Y=(F=0,X);F<h;F++)Y+=Q,$=Math.floor(Y),q=Math.max(u[F],U),0!=c&&(_=c-q,i.fillStyle=W,i.fillRect($,_,O,q)),c!=l&&(i.fillStyle=A,i.fillRect($,c,O,q)),Y+=O;if(a.stripeEnable){var Z=a.stripeShadowBlur;i.shadowBlur=(-1==Z?a.shadowBlur:Z)*o,i.shadowColor=a.stripeShadowColor||a.shadowColor;var $,_,tt=a.stripeHeight*o;for(F=0,Y=X;F<h;F++)Y+=Q,$=Math.floor(Y),q=w[F],0!=c&&((_=c-q-tt)<0&&(_=0),i.fillStyle=k,i.fillRect($,_,O,tt)),c!=l&&(l<(_=c+q)+tt&&(_=l-tt),i.fillStyle=G,i.fillRect($,_,O,tt)),Y+=O}if(V){var et=Math.floor(n/2);i.save(),i.scale(-1,1),i.drawImage(r.canvas,Math.ceil(n/2),0,et,l,-et,0,et,l),i.restore()}a.onDraw(t,e)}},Recorder[d]=t}();