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Fast and advanced PNG (APNG) decoder and encoder (lossy / lossless)
此脚本不应直接安装,它是一个供其他脚本使用的外部库。如果您需要使用该库,请在脚本元属性加入:// @require https://update.greasyfork.org/scripts/452821/1103227/UPNGjs.js
var UPNG = {}; UPNG.toRGBA8 = function(out) { var w = out.width, h = out.height; if(out.tabs.acTL==null) return [UPNG.toRGBA8.decodeImage(out.data, w, h, out).buffer]; var frms = []; if(out.frames[0].data==null) out.frames[0].data = out.data; var len = w*h*4, img = new Uint8Array(len), empty = new Uint8Array(len), prev=new Uint8Array(len); for(var i=0; i<out.frames.length; i++) { var frm = out.frames[i]; var fx=frm.rect.x, fy=frm.rect.y, fw = frm.rect.width, fh = frm.rect.height; var fdata = UPNG.toRGBA8.decodeImage(frm.data, fw,fh, out); if(i!=0) for(var j=0; j<len; j++) prev[j]=img[j]; if (frm.blend==0) UPNG._copyTile(fdata, fw, fh, img, w, h, fx, fy, 0); else if(frm.blend==1) UPNG._copyTile(fdata, fw, fh, img, w, h, fx, fy, 1); frms.push(img.buffer.slice(0)); if (frm.dispose==0) {} else if(frm.dispose==1) UPNG._copyTile(empty, fw, fh, img, w, h, fx, fy, 0); else if(frm.dispose==2) for(var j=0; j<len; j++) img[j]=prev[j]; } return frms; } UPNG.toRGBA8.decodeImage = function(data, w, h, out) { var area = w*h, bpp = UPNG.decode._getBPP(out); var bpl = Math.ceil(w*bpp/8); // bytes per line var bf = new Uint8Array(area*4), bf32 = new Uint32Array(bf.buffer); var ctype = out.ctype, depth = out.depth; var rs = UPNG._bin.readUshort; //console.log(ctype, depth); var time = Date.now(); if (ctype==6) { // RGB + alpha var qarea = area<<2; if(depth== 8) for(var i=0; i<qarea;i+=4) { bf[i] = data[i]; bf[i+1] = data[i+1]; bf[i+2] = data[i+2]; bf[i+3] = data[i+3]; } if(depth==16) for(var i=0; i<qarea;i++ ) { bf[i] = data[i<<1]; } } else if(ctype==2) { // RGB var ts=out.tabs["tRNS"]; if(ts==null) { if(depth== 8) for(var i=0; i<area; i++) { var ti=i*3; bf32[i] = (255<<24)|(data[ti+2]<<16)|(data[ti+1]<<8)|data[ti]; } if(depth==16) for(var i=0; i<area; i++) { var ti=i*6; bf32[i] = (255<<24)|(data[ti+4]<<16)|(data[ti+2]<<8)|data[ti]; } } else { var tr=ts[0], tg=ts[1], tb=ts[2]; if(depth== 8) for(var i=0; i<area; i++) { var qi=i<<2, ti=i*3; bf32[i] = (255<<24)|(data[ti+2]<<16)|(data[ti+1]<<8)|data[ti]; if(data[ti] ==tr && data[ti+1] ==tg && data[ti+2] ==tb) bf[qi+3] = 0; } if(depth==16) for(var i=0; i<area; i++) { var qi=i<<2, ti=i*6; bf32[i] = (255<<24)|(data[ti+4]<<16)|(data[ti+2]<<8)|data[ti]; if(rs(data,ti)==tr && rs(data,ti+2)==tg && rs(data,ti+4)==tb) bf[qi+3] = 0; } } } else if(ctype==3) { // palette var p=out.tabs["PLTE"], ap=out.tabs["tRNS"], tl=ap?ap.length:0; //console.log(p, ap); if(depth==1) for(var y=0; y<h; y++) { var s0 = y*bpl, t0 = y*w; for(var i=0; i<w; i++) { var qi=(t0+i)<<2, j=((data[s0+(i>>3)]>>(7-((i&7)<<0)))& 1), cj=3*j; bf[qi]=p[cj]; bf[qi+1]=p[cj+1]; bf[qi+2]=p[cj+2]; bf[qi+3]=(j<tl)?ap[j]:255; } } if(depth==2) for(var y=0; y<h; y++) { var s0 = y*bpl, t0 = y*w; for(var i=0; i<w; i++) { var qi=(t0+i)<<2, j=((data[s0+(i>>2)]>>(6-((i&3)<<1)))& 3), cj=3*j; bf[qi]=p[cj]; bf[qi+1]=p[cj+1]; bf[qi+2]=p[cj+2]; bf[qi+3]=(j<tl)?ap[j]:255; } } if(depth==4) for(var y=0; y<h; y++) { var s0 = y*bpl, t0 = y*w; for(var i=0; i<w; i++) { var qi=(t0+i)<<2, j=((data[s0+(i>>1)]>>(4-((i&1)<<2)))&15), cj=3*j; bf[qi]=p[cj]; bf[qi+1]=p[cj+1]; bf[qi+2]=p[cj+2]; bf[qi+3]=(j<tl)?ap[j]:255; } } if(depth==8) for(var i=0; i<area; i++ ) { var qi=i<<2, j=data[i] , cj=3*j; bf[qi]=p[cj]; bf[qi+1]=p[cj+1]; bf[qi+2]=p[cj+2]; bf[qi+3]=(j<tl)?ap[j]:255; } } else if(ctype==4) { // gray + alpha if(depth== 8) for(var i=0; i<area; i++) { var qi=i<<2, di=i<<1, gr=data[di]; bf[qi]=gr; bf[qi+1]=gr; bf[qi+2]=gr; bf[qi+3]=data[di+1]; } if(depth==16) for(var i=0; i<area; i++) { var qi=i<<2, di=i<<2, gr=data[di]; bf[qi]=gr; bf[qi+1]=gr; bf[qi+2]=gr; bf[qi+3]=data[di+2]; } } else if(ctype==0) { // gray var tr = out.tabs["tRNS"] ? out.tabs["tRNS"] : -1; for(var y=0; y<h; y++) { var off = y*bpl, to = y*w; if (depth== 1) for(var x=0; x<w; x++) { var gr=255*((data[off+(x>>>3)]>>>(7 -((x&7) )))& 1), al=(gr==tr*255)?0:255; bf32[to+x]=(al<<24)|(gr<<16)|(gr<<8)|gr; } else if(depth== 2) for(var x=0; x<w; x++) { var gr= 85*((data[off+(x>>>2)]>>>(6 -((x&3)<<1)))& 3), al=(gr==tr* 85)?0:255; bf32[to+x]=(al<<24)|(gr<<16)|(gr<<8)|gr; } else if(depth== 4) for(var x=0; x<w; x++) { var gr= 17*((data[off+(x>>>1)]>>>(4 -((x&1)<<2)))&15), al=(gr==tr* 17)?0:255; bf32[to+x]=(al<<24)|(gr<<16)|(gr<<8)|gr; } else if(depth== 8) for(var x=0; x<w; x++) { var gr=data[off+ x], al=(gr ==tr)?0:255; bf32[to+x]=(al<<24)|(gr<<16)|(gr<<8)|gr; } else if(depth==16) for(var x=0; x<w; x++) { var gr=data[off+(x<<1)], al=(rs(data,off+(x<<1))==tr)?0:255; bf32[to+x]=(al<<24)|(gr<<16)|(gr<<8)|gr; } } } //console.log(Date.now()-time); return bf; } UPNG.decode = function(buff) { var data = new Uint8Array(buff), offset = 8, bin = UPNG._bin, rUs = bin.readUshort, rUi = bin.readUint; var out = {tabs:{}, frames:[]}; var dd = new Uint8Array(data.length), doff = 0; // put all IDAT data into it var fd, foff = 0; // frames var mgck = [0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a]; for(var i=0; i<8; i++) if(data[i]!=mgck[i]) throw "The input is not a PNG file!"; while(offset<data.length) { var len = bin.readUint(data, offset); offset += 4; var type = bin.readASCII(data, offset, 4); offset += 4; //console.log(type,len); if (type=="IHDR") { UPNG.decode._IHDR(data, offset, out); } else if(type=="CgBI") { out.tabs[type] = data.slice(offset,offset+4); } else if(type=="IDAT") { for(var i=0; i<len; i++) dd[doff+i] = data[offset+i]; doff += len; } else if(type=="acTL") { out.tabs[type] = { num_frames:rUi(data, offset), num_plays:rUi(data, offset+4) }; fd = new Uint8Array(data.length); } else if(type=="fcTL") { if(foff!=0) { var fr = out.frames[out.frames.length-1]; fr.data = UPNG.decode._decompress(out, fd.slice(0,foff), fr.rect.width, fr.rect.height); foff=0; } var rct = {x:rUi(data, offset+12),y:rUi(data, offset+16),width:rUi(data, offset+4),height:rUi(data, offset+8)}; var del = rUs(data, offset+22); del = rUs(data, offset+20) / (del==0?100:del); var frm = {rect:rct, delay:Math.round(del*1000), dispose:data[offset+24], blend:data[offset+25]}; //console.log(frm); out.frames.push(frm); } else if(type=="fdAT") { for(var i=0; i<len-4; i++) fd[foff+i] = data[offset+i+4]; foff += len-4; } else if(type=="pHYs") { out.tabs[type] = [bin.readUint(data, offset), bin.readUint(data, offset+4), data[offset+8]]; } else if(type=="cHRM") { out.tabs[type] = []; for(var i=0; i<8; i++) out.tabs[type].push(bin.readUint(data, offset+i*4)); } else if(type=="tEXt" || type=="zTXt") { if(out.tabs[type]==null) out.tabs[type] = {}; var nz = bin.nextZero(data, offset); var keyw = bin.readASCII(data, offset, nz-offset); var text, tl=offset+len-nz-1; if(type=="tEXt") text = bin.readASCII(data, nz+1, tl); else { var bfr = UPNG.decode._inflate(data.slice(nz+2,nz+2+tl)); text = bin.readUTF8(bfr,0,bfr.length); } out.tabs[type][keyw] = text; } else if(type=="iTXt") { if(out.tabs[type]==null) out.tabs[type] = {}; var nz = 0, off = offset; nz = bin.nextZero(data, off); var keyw = bin.readASCII(data, off, nz-off); off = nz + 1; var cflag = data[off], cmeth = data[off+1]; off+=2; nz = bin.nextZero(data, off); var ltag = bin.readASCII(data, off, nz-off); off = nz + 1; nz = bin.nextZero(data, off); var tkeyw = bin.readUTF8(data, off, nz-off); off = nz + 1; var text, tl=len-(off-offset); if(cflag==0) text = bin.readUTF8(data, off, tl); else { var bfr = UPNG.decode._inflate(data.slice(off,off+tl)); text = bin.readUTF8(bfr,0,bfr.length); } out.tabs[type][keyw] = text; } else if(type=="PLTE") { out.tabs[type] = bin.readBytes(data, offset, len); } else if(type=="hIST") { var pl = out.tabs["PLTE"].length/3; out.tabs[type] = []; for(var i=0; i<pl; i++) out.tabs[type].push(rUs(data, offset+i*2)); } else if(type=="tRNS") { if (out.ctype==3) out.tabs[type] = bin.readBytes(data, offset, len); else if(out.ctype==0) out.tabs[type] = rUs(data, offset); else if(out.ctype==2) out.tabs[type] = [ rUs(data,offset),rUs(data,offset+2),rUs(data,offset+4) ]; //else console.log("tRNS for unsupported color type",out.ctype, len); } else if(type=="gAMA") out.tabs[type] = bin.readUint(data, offset)/100000; else if(type=="sRGB") out.tabs[type] = data[offset]; else if(type=="bKGD") { if (out.ctype==0 || out.ctype==4) out.tabs[type] = [rUs(data, offset)]; else if(out.ctype==2 || out.ctype==6) out.tabs[type] = [rUs(data, offset), rUs(data, offset+2), rUs(data, offset+4)]; else if(out.ctype==3) out.tabs[type] = data[offset]; } else if(type=="IEND") { break; } //else { console.log("unknown chunk type", type, len); out.tabs[type]=data.slice(offset,offset+len); } offset += len; var crc = bin.readUint(data, offset); offset += 4; } if(foff!=0) { var fr = out.frames[out.frames.length-1]; fr.data = UPNG.decode._decompress(out, fd.slice(0,foff), fr.rect.width, fr.rect.height); } out.data = UPNG.decode._decompress(out, dd, out.width, out.height); delete out.compress; delete out.interlace; delete out.filter; return out; } UPNG.decode._decompress = function(out, dd, w, h) { var time = Date.now(); var bpp = UPNG.decode._getBPP(out), bpl = Math.ceil(w*bpp/8), buff = new Uint8Array((bpl+1+out.interlace)*h); if(out.tabs["CgBI"]) dd = UPNG.inflateRaw(dd,buff); else dd = UPNG.decode._inflate(dd,buff); //console.log(dd.length, buff.length); //console.log(Date.now()-time); var time=Date.now(); if (out.interlace==0) dd = UPNG.decode._filterZero(dd, out, 0, w, h); else if(out.interlace==1) dd = UPNG.decode._readInterlace(dd, out); //console.log(Date.now()-time); return dd; } UPNG.decode._inflate = function(data, buff) { var out=UPNG["inflateRaw"](new Uint8Array(data.buffer, 2,data.length-6),buff); return out; } UPNG.inflateRaw=function(){var H={};H.H={};H.H.N=function(N,W){var R=Uint8Array,i=0,m=0,J=0,h=0,Q=0,X=0,u=0,w=0,d=0,v,C; if(N[0]==3&&N[1]==0)return W?W:new R(0);var V=H.H,n=V.b,A=V.e,l=V.R,M=V.n,I=V.A,e=V.Z,b=V.m,Z=W==null; if(Z)W=new R(N.length>>>2<<5);while(i==0){i=n(N,d,1);m=n(N,d+1,2);d+=3;if(m==0){if((d&7)!=0)d+=8-(d&7); var D=(d>>>3)+4,q=N[D-4]|N[D-3]<<8;if(Z)W=H.H.W(W,w+q);W.set(new R(N.buffer,N.byteOffset+D,q),w);d=D+q<<3; w+=q;continue}if(Z)W=H.H.W(W,w+(1<<17));if(m==1){v=b.J;C=b.h;X=(1<<9)-1;u=(1<<5)-1}if(m==2){J=A(N,d,5)+257; h=A(N,d+5,5)+1;Q=A(N,d+10,4)+4;d+=14;var E=d,j=1;for(var c=0;c<38;c+=2){b.Q[c]=0;b.Q[c+1]=0}for(var c=0; c<Q;c++){var K=A(N,d+c*3,3);b.Q[(b.X[c]<<1)+1]=K;if(K>j)j=K}d+=3*Q;M(b.Q,j);I(b.Q,j,b.u);v=b.w;C=b.d; d=l(b.u,(1<<j)-1,J+h,N,d,b.v);var r=V.V(b.v,0,J,b.C);X=(1<<r)-1;var S=V.V(b.v,J,h,b.D);u=(1<<S)-1;M(b.C,r); I(b.C,r,v);M(b.D,S);I(b.D,S,C)}while(!0){var T=v[e(N,d)&X];d+=T&15;var p=T>>>4;if(p>>>8==0){W[w++]=p}else if(p==256){break}else{var z=w+p-254; if(p>264){var _=b.q[p-257];z=w+(_>>>3)+A(N,d,_&7);d+=_&7}var $=C[e(N,d)&u];d+=$&15;var s=$>>>4,Y=b.c[s],a=(Y>>>4)+n(N,d,Y&15); d+=Y&15;while(w<z){W[w]=W[w++-a];W[w]=W[w++-a];W[w]=W[w++-a];W[w]=W[w++-a]}w=z}}}return W.length==w?W:W.slice(0,w)}; H.H.W=function(N,W){var R=N.length;if(W<=R)return N;var V=new Uint8Array(R<<1);V.set(N,0);return V}; H.H.R=function(N,W,R,V,n,A){var l=H.H.e,M=H.H.Z,I=0;while(I<R){var e=N[M(V,n)&W];n+=e&15;var b=e>>>4; if(b<=15){A[I]=b;I++}else{var Z=0,m=0;if(b==16){m=3+l(V,n,2);n+=2;Z=A[I-1]}else if(b==17){m=3+l(V,n,3); n+=3}else if(b==18){m=11+l(V,n,7);n+=7}var J=I+m;while(I<J){A[I]=Z;I++}}}return n};H.H.V=function(N,W,R,V){var n=0,A=0,l=V.length>>>1; while(A<R){var M=N[A+W];V[A<<1]=0;V[(A<<1)+1]=M;if(M>n)n=M;A++}while(A<l){V[A<<1]=0;V[(A<<1)+1]=0;A++}return n}; H.H.n=function(N,W){var R=H.H.m,V=N.length,n,A,l,M,I,e=R.j;for(var M=0;M<=W;M++)e[M]=0;for(M=1;M<V;M+=2)e[N[M]]++; var b=R.K;n=0;e[0]=0;for(A=1;A<=W;A++){n=n+e[A-1]<<1;b[A]=n}for(l=0;l<V;l+=2){I=N[l+1];if(I!=0){N[l]=b[I]; b[I]++}}};H.H.A=function(N,W,R){var V=N.length,n=H.H.m,A=n.r;for(var l=0;l<V;l+=2)if(N[l+1]!=0){var M=l>>1,I=N[l+1],e=M<<4|I,b=W-I,Z=N[l]<<b,m=Z+(1<<b); while(Z!=m){var J=A[Z]>>>15-W;R[J]=e;Z++}}};H.H.l=function(N,W){var R=H.H.m.r,V=15-W;for(var n=0;n<N.length; n+=2){var A=N[n]<<W-N[n+1];N[n]=R[A]>>>V}};H.H.M=function(N,W,R){R=R<<(W&7);var V=W>>>3;N[V]|=R;N[V+1]|=R>>>8}; H.H.I=function(N,W,R){R=R<<(W&7);var V=W>>>3;N[V]|=R;N[V+1]|=R>>>8;N[V+2]|=R>>>16};H.H.e=function(N,W,R){return(N[W>>>3]|N[(W>>>3)+1]<<8)>>>(W&7)&(1<<R)-1}; H.H.b=function(N,W,R){return(N[W>>>3]|N[(W>>>3)+1]<<8|N[(W>>>3)+2]<<16)>>>(W&7)&(1<<R)-1};H.H.Z=function(N,W){return(N[W>>>3]|N[(W>>>3)+1]<<8|N[(W>>>3)+2]<<16)>>>(W&7)}; H.H.i=function(N,W){return(N[W>>>3]|N[(W>>>3)+1]<<8|N[(W>>>3)+2]<<16|N[(W>>>3)+3]<<24)>>>(W&7)};H.H.m=function(){var N=Uint16Array,W=Uint32Array; return{K:new N(16),j:new N(16),X:[16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15],S:[3,4,5,6,7,8,9,10,11,13,15,17,19,23,27,31,35,43,51,59,67,83,99,115,131,163,195,227,258,999,999,999],T:[0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0,0,0,0],q:new N(32),p:[1,2,3,4,5,7,9,13,17,25,33,49,65,97,129,193,257,385,513,769,1025,1537,2049,3073,4097,6145,8193,12289,16385,24577,65535,65535],z:[0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13,0,0],c:new W(32),J:new N(512),_:[],h:new N(32),$:[],w:new N(32768),C:[],v:[],d:new N(32768),D:[],u:new N(512),Q:[],r:new N(1<<15),s:new W(286),Y:new W(30),a:new W(19),t:new W(15e3),k:new N(1<<16),g:new N(1<<15)}}(); (function(){var N=H.H.m,W=1<<15;for(var R=0;R<W;R++){var V=R;V=(V&2863311530)>>>1|(V&1431655765)<<1; V=(V&3435973836)>>>2|(V&858993459)<<2;V=(V&4042322160)>>>4|(V&252645135)<<4;V=(V&4278255360)>>>8|(V&16711935)<<8; N.r[R]=(V>>>16|V<<16)>>>17}function n(A,l,M){while(l--!=0)A.push(0,M)}for(var R=0;R<32;R++){N.q[R]=N.S[R]<<3|N.T[R]; N.c[R]=N.p[R]<<4|N.z[R]}n(N._,144,8);n(N._,255-143,9);n(N._,279-255,7);n(N._,287-279,8);H.H.n(N._,9); H.H.A(N._,9,N.J);H.H.l(N._,9);n(N.$,32,5);H.H.n(N.$,5);H.H.A(N.$,5,N.h);H.H.l(N.$,5);n(N.Q,19,0);n(N.C,286,0); n(N.D,30,0);n(N.v,320,0)}());return H.H.N}() UPNG.decode._readInterlace = function(data, out) { var w = out.width, h = out.height; var bpp = UPNG.decode._getBPP(out), cbpp = bpp>>3, bpl = Math.ceil(w*bpp/8); var img = new Uint8Array( h * bpl ); var di = 0; var starting_row = [ 0, 0, 4, 0, 2, 0, 1 ]; var starting_col = [ 0, 4, 0, 2, 0, 1, 0 ]; var row_increment = [ 8, 8, 8, 4, 4, 2, 2 ]; var col_increment = [ 8, 8, 4, 4, 2, 2, 1 ]; var pass=0; while(pass<7) { var ri = row_increment[pass], ci = col_increment[pass]; var sw = 0, sh = 0; var cr = starting_row[pass]; while(cr<h) { cr+=ri; sh++; } var cc = starting_col[pass]; while(cc<w) { cc+=ci; sw++; } var bpll = Math.ceil(sw*bpp/8); UPNG.decode._filterZero(data, out, di, sw, sh); var y=0, row = starting_row[pass]; while(row<h) { var col = starting_col[pass]; var cdi = (di+y*bpll)<<3; while(col<w) { if(bpp==1) { var val = data[cdi>>3]; val = (val>>(7-(cdi&7)))&1; img[row*bpl + (col>>3)] |= (val << (7-((col&7)<<0))); } if(bpp==2) { var val = data[cdi>>3]; val = (val>>(6-(cdi&7)))&3; img[row*bpl + (col>>2)] |= (val << (6-((col&3)<<1))); } if(bpp==4) { var val = data[cdi>>3]; val = (val>>(4-(cdi&7)))&15; img[row*bpl + (col>>1)] |= (val << (4-((col&1)<<2))); } if(bpp>=8) { var ii = row*bpl+col*cbpp; for(var j=0; j<cbpp; j++) img[ii+j] = data[(cdi>>3)+j]; } cdi+=bpp; col+=ci; } y++; row += ri; } if(sw*sh!=0) di += sh * (1 + bpll); pass = pass + 1; } return img; } UPNG.decode._getBPP = function(out) { var noc = [1,null,3,1,2,null,4][out.ctype]; return noc * out.depth; } UPNG.decode._filterZero = function(data, out, off, w, h) { var bpp = UPNG.decode._getBPP(out), bpl = Math.ceil(w*bpp/8), paeth = UPNG.decode._paeth; bpp = Math.ceil(bpp/8); var i,di, type=data[off], x=0; if(type>1) data[off]=[0,0,1][type-2]; if(type==3) for(x=bpp; x<bpl; x++) data[x+1] = (data[x+1] + (data[x+1-bpp]>>>1) )&255; for(var y=0; y<h; y++) { i = off+y*bpl; di = i+y+1; type = data[di-1]; x=0; if (type==0) for(; x<bpl; x++) data[i+x] = data[di+x]; else if(type==1) { for(; x<bpp; x++) data[i+x] = data[di+x]; for(; x<bpl; x++) data[i+x] = (data[di+x] + data[i+x-bpp]); } else if(type==2) { for(; x<bpl; x++) data[i+x] = (data[di+x] + data[i+x-bpl]); } else if(type==3) { for(; x<bpp; x++) data[i+x] = (data[di+x] + ( data[i+x-bpl]>>>1)); for(; x<bpl; x++) data[i+x] = (data[di+x] + ((data[i+x-bpl]+data[i+x-bpp])>>>1) ); } else { for(; x<bpp; x++) data[i+x] = (data[di+x] + paeth(0, data[i+x-bpl], 0)); for(; x<bpl; x++) data[i+x] = (data[di+x] + paeth(data[i+x-bpp], data[i+x-bpl], data[i+x-bpp-bpl]) ); } } return data; } UPNG.decode._paeth = function(a,b,c) { var p = a+b-c, pa = (p-a), pb = (p-b), pc = (p-c); if (pa*pa <= pb*pb && pa*pa <= pc*pc) return a; else if (pb*pb <= pc*pc) return b; return c; } UPNG.decode._IHDR = function(data, offset, out) { var bin = UPNG._bin; out.width = bin.readUint(data, offset); offset += 4; out.height = bin.readUint(data, offset); offset += 4; out.depth = data[offset]; offset++; out.ctype = data[offset]; offset++; out.compress = data[offset]; offset++; out.filter = data[offset]; offset++; out.interlace = data[offset]; offset++; } UPNG._bin = { nextZero : function(data,p) { while(data[p]!=0) p++; return p; }, readUshort : function(buff,p) { return (buff[p]<< 8) | buff[p+1]; }, writeUshort: function(buff,p,n){ buff[p] = (n>>8)&255; buff[p+1] = n&255; }, readUint : function(buff,p) { return (buff[p]*(256*256*256)) + ((buff[p+1]<<16) | (buff[p+2]<< 8) | buff[p+3]); }, writeUint : function(buff,p,n){ buff[p]=(n>>24)&255; buff[p+1]=(n>>16)&255; buff[p+2]=(n>>8)&255; buff[p+3]=n&255; }, readASCII : function(buff,p,l){ var s = ""; for(var i=0; i<l; i++) s += String.fromCharCode(buff[p+i]); return s; }, writeASCII : function(data,p,s){ for(var i=0; i<s.length; i++) data[p+i] = s.charCodeAt(i); }, readBytes : function(buff,p,l){ var arr = []; for(var i=0; i<l; i++) arr.push(buff[p+i]); return arr; }, pad : function(n) { return n.length < 2 ? "0" + n : n; }, readUTF8 : function(buff, p, l) { var s = "", ns; for(var i=0; i<l; i++) s += "%" + UPNG._bin.pad(buff[p+i].toString(16)); try { ns = decodeURIComponent(s); } catch(e) { return UPNG._bin.readASCII(buff, p, l); } return ns; } } UPNG._copyTile = function(sb, sw, sh, tb, tw, th, xoff, yoff, mode) { var w = Math.min(sw,tw), h = Math.min(sh,th); var si=0, ti=0; for(var y=0; y<h; y++) for(var x=0; x<w; x++) { if(xoff>=0 && yoff>=0) { si = (y*sw+x)<<2; ti = (( yoff+y)*tw+xoff+x)<<2; } else { si = ((-yoff+y)*sw-xoff+x)<<2; ti = (y*tw+x)<<2; } if (mode==0) { tb[ti] = sb[si]; tb[ti+1] = sb[si+1]; tb[ti+2] = sb[si+2]; tb[ti+3] = sb[si+3]; } else if(mode==1) { var fa = sb[si+3]*(1/255), fr=sb[si]*fa, fg=sb[si+1]*fa, fb=sb[si+2]*fa; var ba = tb[ti+3]*(1/255), br=tb[ti]*ba, bg=tb[ti+1]*ba, bb=tb[ti+2]*ba; var ifa=1-fa, oa = fa+ba*ifa, ioa = (oa==0?0:1/oa); tb[ti+3] = 255*oa; tb[ti+0] = (fr+br*ifa)*ioa; tb[ti+1] = (fg+bg*ifa)*ioa; tb[ti+2] = (fb+bb*ifa)*ioa; } else if(mode==2){ // copy only differences, otherwise zero var fa = sb[si+3], fr=sb[si], fg=sb[si+1], fb=sb[si+2]; var ba = tb[ti+3], br=tb[ti], bg=tb[ti+1], bb=tb[ti+2]; if(fa==ba && fr==br && fg==bg && fb==bb) { tb[ti]=0; tb[ti+1]=0; tb[ti+2]=0; tb[ti+3]=0; } else { tb[ti]=fr; tb[ti+1]=fg; tb[ti+2]=fb; tb[ti+3]=fa; } } else if(mode==3){ // check if can be blended var fa = sb[si+3], fr=sb[si], fg=sb[si+1], fb=sb[si+2]; var ba = tb[ti+3], br=tb[ti], bg=tb[ti+1], bb=tb[ti+2]; if(fa==ba && fr==br && fg==bg && fb==bb) continue; //if(fa!=255 && ba!=0) return false; if(fa<220 && ba>20) return false; } } return true; } UPNG.encode = function(bufs, w, h, ps, dels, tabs, forbidPlte) { if(ps==null) ps=0; if(forbidPlte==null) forbidPlte = false; var nimg = UPNG.encode.compress(bufs, w, h, ps, [false, false, false, 0, forbidPlte,false]); UPNG.encode.compressPNG(nimg, -1); return UPNG.encode._main(nimg, w, h, dels, tabs); } UPNG.encodeLL = function(bufs, w, h, cc, ac, depth, dels, tabs) { var nimg = { ctype: 0 + (cc==1 ? 0 : 2) + (ac==0 ? 0 : 4), depth: depth, frames: [] }; var time = Date.now(); var bipp = (cc+ac)*depth, bipl = bipp * w; for(var i=0; i<bufs.length; i++) nimg.frames.push({ rect:{x:0,y:0,width:w,height:h}, img:new Uint8Array(bufs[i]), blend:0, dispose:1, bpp:Math.ceil(bipp/8), bpl:Math.ceil(bipl/8) }); UPNG.encode.compressPNG(nimg, 0, true); var out = UPNG.encode._main(nimg, w, h, dels, tabs); return out; } UPNG.encode._main = function(nimg, w, h, dels, tabs) { if(tabs==null) tabs={}; var crc = UPNG.crc.crc, wUi = UPNG._bin.writeUint, wUs = UPNG._bin.writeUshort, wAs = UPNG._bin.writeASCII; var offset = 8, anim = nimg.frames.length>1, pltAlpha = false; var leng = 8 + (16+5+4) /*+ (9+4)*/ + (anim ? 20 : 0); if(tabs["sRGB"]!=null) leng += 8+1+4; if(tabs["pHYs"]!=null) leng += 8+9+4; if(nimg.ctype==3) { var dl = nimg.plte.length; for(var i=0; i<dl; i++) if((nimg.plte[i]>>>24)!=255) pltAlpha = true; leng += (8 + dl*3 + 4) + (pltAlpha ? (8 + dl*1 + 4) : 0); } for(var j=0; j<nimg.frames.length; j++) { var fr = nimg.frames[j]; if(anim) leng += 38; leng += fr.cimg.length + 12; if(j!=0) leng+=4; } leng += 12; var data = new Uint8Array(leng); var wr=[0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a]; for(var i=0; i<8; i++) data[i]=wr[i]; wUi(data,offset, 13); offset+=4; wAs(data,offset,"IHDR"); offset+=4; wUi(data,offset,w); offset+=4; wUi(data,offset,h); offset+=4; data[offset] = nimg.depth; offset++; // depth data[offset] = nimg.ctype; offset++; // ctype data[offset] = 0; offset++; // compress data[offset] = 0; offset++; // filter data[offset] = 0; offset++; // interlace wUi(data,offset,crc(data,offset-17,17)); offset+=4; // crc // 13 bytes to say, that it is sRGB if(tabs["sRGB"]!=null) { wUi(data,offset, 1); offset+=4; wAs(data,offset,"sRGB"); offset+=4; data[offset] = tabs["sRGB"]; offset++; wUi(data,offset,crc(data,offset-5,5)); offset+=4; // crc } if(tabs["pHYs"]!=null) { wUi(data,offset, 9); offset+=4; wAs(data,offset,"pHYs"); offset+=4; wUi(data,offset, tabs["pHYs"][0]); offset+=4; wUi(data,offset, tabs["pHYs"][1]); offset+=4; data[offset]=tabs["pHYs"][2]; offset++; wUi(data,offset,crc(data,offset-13,13)); offset+=4; // crc } if(anim) { wUi(data,offset, 8); offset+=4; wAs(data,offset,"acTL"); offset+=4; wUi(data,offset, nimg.frames.length); offset+=4; wUi(data,offset, tabs["loop"]!=null?tabs["loop"]:0); offset+=4; wUi(data,offset,crc(data,offset-12,12)); offset+=4; // crc } if(nimg.ctype==3) { var dl = nimg.plte.length; wUi(data,offset, dl*3); offset+=4; wAs(data,offset,"PLTE"); offset+=4; for(var i=0; i<dl; i++){ var ti=i*3, c=nimg.plte[i], r=(c)&255, g=(c>>>8)&255, b=(c>>>16)&255; data[offset+ti+0]=r; data[offset+ti+1]=g; data[offset+ti+2]=b; } offset+=dl*3; wUi(data,offset,crc(data,offset-dl*3-4,dl*3+4)); offset+=4; // crc if(pltAlpha) { wUi(data,offset, dl); offset+=4; wAs(data,offset,"tRNS"); offset+=4; for(var i=0; i<dl; i++) data[offset+i]=(nimg.plte[i]>>>24)&255; offset+=dl; wUi(data,offset,crc(data,offset-dl-4,dl+4)); offset+=4; // crc } } var fi = 0; for(var j=0; j<nimg.frames.length; j++) { var fr = nimg.frames[j]; if(anim) { wUi(data, offset, 26); offset+=4; wAs(data, offset,"fcTL"); offset+=4; wUi(data, offset, fi++); offset+=4; wUi(data, offset, fr.rect.width ); offset+=4; wUi(data, offset, fr.rect.height); offset+=4; wUi(data, offset, fr.rect.x); offset+=4; wUi(data, offset, fr.rect.y); offset+=4; wUs(data, offset, dels[j]); offset+=2; wUs(data, offset, 1000); offset+=2; data[offset] = fr.dispose; offset++; // dispose data[offset] = fr.blend ; offset++; // blend wUi(data,offset,crc(data,offset-30,30)); offset+=4; // crc } var imgd = fr.cimg, dl = imgd.length; wUi(data,offset, dl+(j==0?0:4)); offset+=4; var ioff = offset; wAs(data,offset,(j==0)?"IDAT":"fdAT"); offset+=4; if(j!=0) { wUi(data, offset, fi++); offset+=4; } data.set(imgd,offset); offset += dl; wUi(data,offset,crc(data,ioff,offset-ioff)); offset+=4; // crc } wUi(data,offset, 0); offset+=4; wAs(data,offset,"IEND"); offset+=4; wUi(data,offset,crc(data,offset-4,4)); offset+=4; // crc return data.buffer; } UPNG.encode.compressPNG = function(out, filter, levelZero) { for(var i=0; i<out.frames.length; i++) { var frm = out.frames[i], nw=frm.rect.width, nh=frm.rect.height; var fdata = new Uint8Array(nh*frm.bpl+nh); frm.cimg = UPNG.encode._filterZero(frm.img,nh,frm.bpp,frm.bpl,fdata, filter, levelZero); } } UPNG.encode.compress = function(bufs, w, h, ps, prms) // prms: onlyBlend, minBits, forbidPlte { //var time = Date.now(); var onlyBlend = prms[0], evenCrd = prms[1], forbidPrev = prms[2], minBits = prms[3], forbidPlte = prms[4], dither=prms[5]; var ctype = 6, depth = 8, alphaAnd=255 for(var j=0; j<bufs.length; j++) { // when not quantized, other frames can contain colors, that are not in an initial frame var img = new Uint8Array(bufs[j]), ilen = img.length; for(var i=0; i<ilen; i+=4) alphaAnd &= img[i+3]; } var gotAlpha = (alphaAnd!=255); //console.log("alpha check", Date.now()-time); time = Date.now(); //var brute = gotAlpha && forGIF; // brute : frames can only be copied, not "blended" var frms = UPNG.encode.framize(bufs, w, h, onlyBlend, evenCrd, forbidPrev); //console.log("framize", Date.now()-time); time = Date.now(); var cmap={}, plte=[], inds=[]; if(ps!=0) { var nbufs = []; for(var i=0; i<frms.length; i++) nbufs.push(frms[i].img.buffer); var abuf = UPNG.encode.concatRGBA(nbufs), qres = UPNG.quantize(abuf, ps); for(var i=0; i<qres.plte.length; i++) plte.push(qres.plte[i].est.rgba); var cof = 0; for(var i=0; i<frms.length; i++) { var frm=frms[i], bln=frm.img.length, ind = new Uint8Array(qres.inds.buffer, cof>>2, bln>>2); inds.push(ind); var bb = new Uint8Array(qres.abuf,cof,bln); //console.log(frm.img, frm.width, frm.height); //var time = Date.now(); if(dither) UPNG.encode.dither(frm.img, frm.rect.width, frm.rect.height, plte, bb, ind); //console.log(Date.now()-time); frm.img.set(bb); cof+=bln; } //console.log("quantize", Date.now()-time); time = Date.now(); } else { // what if ps==0, but there are <=256 colors? we still need to detect, if the palette could be used for(var j=0; j<frms.length; j++) { // when not quantized, other frames can contain colors, that are not in an initial frame var frm = frms[j], img32 = new Uint32Array(frm.img.buffer), nw=frm.rect.width, ilen = img32.length; var ind = new Uint8Array(ilen); inds.push(ind); for(var i=0; i<ilen; i++) { var c = img32[i]; if (i!=0 && c==img32[i- 1]) ind[i]=ind[i-1]; else if(i>nw && c==img32[i-nw]) ind[i]=ind[i-nw]; else { var cmc = cmap[c]; if(cmc==null) { cmap[c]=cmc=plte.length; plte.push(c); if(plte.length>=300) break; } ind[i]=cmc; } } } //console.log("make palette", Date.now()-time); time = Date.now(); } var cc=plte.length; //console.log("colors:",cc); if(cc<=256 && forbidPlte==false) { if(cc<= 2) depth=1; else if(cc<= 4) depth=2; else if(cc<=16) depth=4; else depth=8; depth = Math.max(depth, minBits); } for(var j=0; j<frms.length; j++) { var frm = frms[j], nx=frm.rect.x, ny=frm.rect.y, nw=frm.rect.width, nh=frm.rect.height; var cimg = frm.img, cimg32 = new Uint32Array(cimg.buffer); var bpl = 4*nw, bpp=4; if(cc<=256 && forbidPlte==false) { bpl = Math.ceil(depth*nw/8); var nimg = new Uint8Array(bpl*nh); var inj = inds[j]; for(var y=0; y<nh; y++) { var i=y*bpl, ii=y*nw; if (depth==8) for(var x=0; x<nw; x++) nimg[i+(x) ] = (inj[ii+x] ); else if(depth==4) for(var x=0; x<nw; x++) nimg[i+(x>>1)] |= (inj[ii+x]<<(4-(x&1)*4)); else if(depth==2) for(var x=0; x<nw; x++) nimg[i+(x>>2)] |= (inj[ii+x]<<(6-(x&3)*2)); else if(depth==1) for(var x=0; x<nw; x++) nimg[i+(x>>3)] |= (inj[ii+x]<<(7-(x&7)*1)); } cimg=nimg; ctype=3; bpp=1; } else if(gotAlpha==false && frms.length==1) { // some next "reduced" frames may contain alpha for blending var nimg = new Uint8Array(nw*nh*3), area=nw*nh; for(var i=0; i<area; i++) { var ti=i*3, qi=i*4; nimg[ti]=cimg[qi]; nimg[ti+1]=cimg[qi+1]; nimg[ti+2]=cimg[qi+2]; } cimg=nimg; ctype=2; bpp=3; bpl=3*nw; } frm.img=cimg; frm.bpl=bpl; frm.bpp=bpp; } //console.log("colors => palette indices", Date.now()-time); time = Date.now(); return {ctype:ctype, depth:depth, plte:plte, frames:frms }; } UPNG.encode.framize = function(bufs,w,h,alwaysBlend,evenCrd,forbidPrev) { /* DISPOSE - 0 : no change - 1 : clear to transparent - 2 : retstore to content before rendering (previous frame disposed) BLEND - 0 : replace - 1 : blend */ var frms = []; for(var j=0; j<bufs.length; j++) { var cimg = new Uint8Array(bufs[j]), cimg32 = new Uint32Array(cimg.buffer); var nimg; var nx=0, ny=0, nw=w, nh=h, blend=alwaysBlend?1:0; if(j!=0) { var tlim = (forbidPrev || alwaysBlend || j==1 || frms[j-2].dispose!=0)?1:2, tstp = 0, tarea = 1e9; for(var it=0; it<tlim; it++) { var pimg = new Uint8Array(bufs[j-1-it]), p32 = new Uint32Array(bufs[j-1-it]); var mix=w,miy=h,max=-1,may=-1; for(var y=0; y<h; y++) for(var x=0; x<w; x++) { var i = y*w+x; if(cimg32[i]!=p32[i]) { if(x<mix) mix=x; if(x>max) max=x; if(y<miy) miy=y; if(y>may) may=y; } } if(max==-1) mix=miy=max=may=0; if(evenCrd) { if((mix&1)==1)mix--; if((miy&1)==1)miy--; } var sarea = (max-mix+1)*(may-miy+1); if(sarea<tarea) { tarea = sarea; tstp = it; nx = mix; ny = miy; nw = max-mix+1; nh = may-miy+1; } } // alwaysBlend: pokud zjistím, že blendit nelze, nastavím předchozímu snímku dispose=1. Zajistím, aby obsahoval můj obdélník. var pimg = new Uint8Array(bufs[j-1-tstp]); if(tstp==1) frms[j-1].dispose = 2; nimg = new Uint8Array(nw*nh*4); UPNG._copyTile(pimg,w,h, nimg,nw,nh, -nx,-ny, 0); blend = UPNG._copyTile(cimg,w,h, nimg,nw,nh, -nx,-ny, 3) ? 1 : 0; if(blend==1) UPNG.encode._prepareDiff(cimg,w,h,nimg,{x:nx,y:ny,width:nw,height:nh}); else UPNG._copyTile(cimg,w,h, nimg,nw,nh, -nx,-ny, 0); //UPNG._copyTile(cimg,w,h, nimg,nw,nh, -nx,-ny, blend==1?2:0); } else nimg = cimg.slice(0); // img may be rewritten further ... don't rewrite input frms.push({rect:{x:nx,y:ny,width:nw,height:nh}, img:nimg, blend:blend, dispose:0}); } if(alwaysBlend) for(var j=0; j<frms.length; j++) { var frm = frms[j]; if(frm.blend==1) continue; var r0 = frm.rect, r1 = frms[j-1].rect var miX = Math.min(r0.x, r1.x), miY = Math.min(r0.y, r1.y); var maX = Math.max(r0.x+r0.width, r1.x+r1.width), maY = Math.max(r0.y+r0.height, r1.y+r1.height); var r = {x:miX, y:miY, width:maX-miX, height:maY-miY}; frms[j-1].dispose = 1; if(j-1!=0) UPNG.encode._updateFrame(bufs, w,h,frms, j-1,r, evenCrd); UPNG.encode._updateFrame(bufs, w,h,frms, j ,r, evenCrd); } var area = 0; if(bufs.length!=1) for(var i=0; i<frms.length; i++) { var frm = frms[i]; area += frm.rect.width*frm.rect.height; //if(i==0 || frm.blend!=1) continue; //var ob = new Uint8Array( //console.log(frm.blend, frm.dispose, frm.rect); } //if(area!=0) console.log(area); return frms; } UPNG.encode._updateFrame = function(bufs, w,h, frms, i, r, evenCrd) { var U8 = Uint8Array, U32 = Uint32Array; var pimg = new U8(bufs[i-1]), pimg32 = new U32(bufs[i-1]), nimg = i+1<bufs.length ? new U8(bufs[i+1]):null; var cimg = new U8(bufs[i]), cimg32 = new U32(cimg.buffer); var mix=w,miy=h,max=-1,may=-1; for(var y=0; y<r.height; y++) for(var x=0; x<r.width; x++) { var cx = r.x+x, cy = r.y+y; var j = cy*w+cx, cc = cimg32[j]; // no need to draw transparency, or to dispose it. Or, if writing the same color and the next one does not need transparency. if(cc==0 || (frms[i-1].dispose==0 && pimg32[j]==cc && (nimg==null || nimg[j*4+3]!=0))/**/) {} else { if(cx<mix) mix=cx; if(cx>max) max=cx; if(cy<miy) miy=cy; if(cy>may) may=cy; } } if(max==-1) mix=miy=max=may=0; if(evenCrd) { if((mix&1)==1)mix--; if((miy&1)==1)miy--; } r = {x:mix, y:miy, width:max-mix+1, height:may-miy+1}; var fr = frms[i]; fr.rect = r; fr.blend = 1; fr.img = new Uint8Array(r.width*r.height*4); if(frms[i-1].dispose==0) { UPNG._copyTile(pimg,w,h, fr.img,r.width,r.height, -r.x,-r.y, 0); UPNG.encode._prepareDiff(cimg,w,h,fr.img,r); //UPNG._copyTile(cimg,w,h, fr.img,r.width,r.height, -r.x,-r.y, 2); } else UPNG._copyTile(cimg,w,h, fr.img,r.width,r.height, -r.x,-r.y, 0); } UPNG.encode._prepareDiff = function(cimg, w,h, nimg, rec) { UPNG._copyTile(cimg,w,h, nimg,rec.width,rec.height, -rec.x,-rec.y, 2); /* var n32 = new Uint32Array(nimg.buffer); var og = new Uint8Array(rec.width*rec.height*4), o32 = new Uint32Array(og.buffer); UPNG._copyTile(cimg,w,h, og,rec.width,rec.height, -rec.x,-rec.y, 0); for(var i=4; i<nimg.length; i+=4) { if(nimg[i-1]!=0 && nimg[i+3]==0 && o32[i>>>2]==o32[(i>>>2)-1]) { n32[i>>>2]=o32[i>>>2]; //var j = i, c=p32[(i>>>2)-1]; //while(p32[j>>>2]==c) { n32[j>>>2]=c; j+=4; } } } for(var i=nimg.length-8; i>0; i-=4) { if(nimg[i+7]!=0 && nimg[i+3]==0 && o32[i>>>2]==o32[(i>>>2)+1]) { n32[i>>>2]=o32[i>>>2]; //var j = i, c=p32[(i>>>2)-1]; //while(p32[j>>>2]==c) { n32[j>>>2]=c; j+=4; } } }*/ } UPNG.encode._filterZero = function(img,h,bpp,bpl,data, filter, levelZero) { var fls = [], ftry=[0,1,2,3,4]; if (filter!=-1) ftry=[filter]; else if(h*bpl>500000 || bpp==1) ftry=[0]; var opts; if(levelZero) opts={level:0}; var CMPR = (data.length>10e6 && UZIP!=null) ? UZIP : pako; var time = Date.now(); for(var i=0; i<ftry.length; i++) { for(var y=0; y<h; y++) UPNG.encode._filterLine(data, img, y, bpl, bpp, ftry[i]); //var nimg = new Uint8Array(data.length); //var sz = UZIP.F.deflate(data, nimg); fls.push(nimg.slice(0,sz)); //var dfl = pako["deflate"](data), dl=dfl.length-4; //var crc = (dfl[dl+3]<<24)|(dfl[dl+2]<<16)|(dfl[dl+1]<<8)|(dfl[dl+0]<<0); //console.log(crc, UZIP.adler(data,2,data.length-6)); fls.push(CMPR["deflate"](data,opts)); } var ti, tsize=1e9; for(var i=0; i<fls.length; i++) if(fls[i].length<tsize) { ti=i; tsize=fls[i].length; } return fls[ti]; } UPNG.encode._filterLine = function(data, img, y, bpl, bpp, type) { var i = y*bpl, di = i+y, paeth = UPNG.decode._paeth data[di]=type; di++; if(type==0) { if(bpl<500) for(var x=0; x<bpl; x++) data[di+x] = img[i+x]; else data.set(new Uint8Array(img.buffer,i,bpl),di); } else if(type==1) { for(var x= 0; x<bpp; x++) data[di+x] = img[i+x]; for(var x=bpp; x<bpl; x++) data[di+x] = (img[i+x]-img[i+x-bpp]+256)&255; } else if(y==0) { for(var x= 0; x<bpp; x++) data[di+x] = img[i+x]; if(type==2) for(var x=bpp; x<bpl; x++) data[di+x] = img[i+x]; if(type==3) for(var x=bpp; x<bpl; x++) data[di+x] = (img[i+x] - (img[i+x-bpp]>>1) +256)&255; if(type==4) for(var x=bpp; x<bpl; x++) data[di+x] = (img[i+x] - paeth(img[i+x-bpp], 0, 0) +256)&255; } else { if(type==2) { for(var x= 0; x<bpl; x++) data[di+x] = (img[i+x]+256 - img[i+x-bpl])&255; } if(type==3) { for(var x= 0; x<bpp; x++) data[di+x] = (img[i+x]+256 - (img[i+x-bpl]>>1))&255; for(var x=bpp; x<bpl; x++) data[di+x] = (img[i+x]+256 - ((img[i+x-bpl]+img[i+x-bpp])>>1))&255; } if(type==4) { for(var x= 0; x<bpp; x++) data[di+x] = (img[i+x]+256 - paeth(0, img[i+x-bpl], 0))&255; for(var x=bpp; x<bpl; x++) data[di+x] = (img[i+x]+256 - paeth(img[i+x-bpp], img[i+x-bpl], img[i+x-bpp-bpl]))&255; } } } UPNG.crc = { table : ( function() { var tab = new Uint32Array(256); for (var n=0; n<256; n++) { var c = n; for (var k=0; k<8; k++) { if (c & 1) c = 0xedb88320 ^ (c >>> 1); else c = c >>> 1; } tab[n] = c; } return tab; })(), update : function(c, buf, off, len) { for (var i=0; i<len; i++) c = UPNG.crc.table[(c ^ buf[off+i]) & 0xff] ^ (c >>> 8); return c; }, crc : function(b,o,l) { return UPNG.crc.update(0xffffffff,b,o,l) ^ 0xffffffff; } } UPNG.quantize = function(abuf, ps) { var sb = new Uint8Array(abuf), tb = sb.slice(0), tb32 = new Uint32Array(tb.buffer); var KD = UPNG.quantize.getKDtree(tb, ps); var root = KD[0], leafs = KD[1]; var planeDst = UPNG.quantize.planeDst; var len=sb.length; var inds = new Uint8Array(len>>2), nd; if(sb.length<20e6) // precise, but slow :( for(var i=0; i<len; i+=4) { var r=sb[i]*(1/255), g=sb[i+1]*(1/255), b=sb[i+2]*(1/255), a=sb[i+3]*(1/255); nd = UPNG.quantize.getNearest(root, r, g, b, a); inds[i>>2] = nd.ind; tb32[i>>2] = nd.est.rgba; } else for(var i=0; i<len; i+=4) { var r=sb[i]*(1/255), g=sb[i+1]*(1/255), b=sb[i+2]*(1/255), a=sb[i+3]*(1/255); nd = root; while(nd.left) nd = (planeDst(nd.est,r,g,b,a)<=0) ? nd.left : nd.right; inds[i>>2] = nd.ind; tb32[i>>2] = nd.est.rgba; } return { abuf:tb.buffer, inds:inds, plte:leafs }; } UPNG.quantize.getKDtree = function(nimg, ps, err) { if(err==null) err = 0.0001; var nimg32 = new Uint32Array(nimg.buffer); var root = {i0:0, i1:nimg.length, bst:null, est:null, tdst:0, left:null, right:null }; // basic statistic, extra statistic root.bst = UPNG.quantize.stats( nimg,root.i0, root.i1 ); root.est = UPNG.quantize.estats( root.bst ); var leafs = [root]; while(leafs.length<ps) { var maxL = 0, mi=0; for(var i=0; i<leafs.length; i++) if(leafs[i].est.L > maxL) { maxL=leafs[i].est.L; mi=i; } if(maxL<err) break; var node = leafs[mi]; var s0 = UPNG.quantize.splitPixels(nimg,nimg32, node.i0, node.i1, node.est.e, node.est.eMq255); var s0wrong = (node.i0>=s0 || node.i1<=s0); //console.log(maxL, leafs.length, mi); if(s0wrong) { node.est.L=0; continue; } var ln = {i0:node.i0, i1:s0, bst:null, est:null, tdst:0, left:null, right:null }; ln.bst = UPNG.quantize.stats( nimg, ln.i0, ln.i1 ); ln.est = UPNG.quantize.estats( ln.bst ); var rn = {i0:s0, i1:node.i1, bst:null, est:null, tdst:0, left:null, right:null }; rn.bst = {R:[], m:[], N:node.bst.N-ln.bst.N}; for(var i=0; i<16; i++) rn.bst.R[i] = node.bst.R[i]-ln.bst.R[i]; for(var i=0; i< 4; i++) rn.bst.m[i] = node.bst.m[i]-ln.bst.m[i]; rn.est = UPNG.quantize.estats( rn.bst ); node.left = ln; node.right = rn; leafs[mi]=ln; leafs.push(rn); } leafs.sort(function(a,b) { return b.bst.N-a.bst.N; }); for(var i=0; i<leafs.length; i++) leafs[i].ind=i; return [root, leafs]; } UPNG.quantize.getNearest = function(nd, r,g,b,a) { if(nd.left==null) { nd.tdst = UPNG.quantize.dist(nd.est.q,r,g,b,a); return nd; } var planeDst = UPNG.quantize.planeDst(nd.est,r,g,b,a); var node0 = nd.left, node1 = nd.right; if(planeDst>0) { node0=nd.right; node1=nd.left; } var ln = UPNG.quantize.getNearest(node0, r,g,b,a); if(ln.tdst<=planeDst*planeDst) return ln; var rn = UPNG.quantize.getNearest(node1, r,g,b,a); return rn.tdst<ln.tdst ? rn : ln; } UPNG.quantize.planeDst = function(est, r,g,b,a) { var e = est.e; return e[0]*r + e[1]*g + e[2]*b + e[3]*a - est.eMq; } UPNG.quantize.dist = function(q, r,g,b,a) { var d0=r-q[0], d1=g-q[1], d2=b-q[2], d3=a-q[3]; return d0*d0+d1*d1+d2*d2+d3*d3; } UPNG.quantize.splitPixels = function(nimg, nimg32, i0, i1, e, eMq) { var vecDot = UPNG.quantize.vecDot; i1-=4; var shfs = 0; while(i0<i1) { while(vecDot(nimg, i0, e)<=eMq) i0+=4; while(vecDot(nimg, i1, e)> eMq) i1-=4; if(i0>=i1) break; var t = nimg32[i0>>2]; nimg32[i0>>2] = nimg32[i1>>2]; nimg32[i1>>2]=t; i0+=4; i1-=4; } while(vecDot(nimg, i0, e)>eMq) i0-=4; return i0+4; } UPNG.quantize.vecDot = function(nimg, i, e) { return nimg[i]*e[0] + nimg[i+1]*e[1] + nimg[i+2]*e[2] + nimg[i+3]*e[3]; } UPNG.quantize.stats = function(nimg, i0, i1){ var R = [0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0]; var m = [0,0,0,0]; var N = (i1-i0)>>2; for(var i=i0; i<i1; i+=4) { var r = nimg[i]*(1/255), g = nimg[i+1]*(1/255), b = nimg[i+2]*(1/255), a = nimg[i+3]*(1/255); //var r = nimg[i], g = nimg[i+1], b = nimg[i+2], a = nimg[i+3]; m[0]+=r; m[1]+=g; m[2]+=b; m[3]+=a; R[ 0] += r*r; R[ 1] += r*g; R[ 2] += r*b; R[ 3] += r*a; R[ 5] += g*g; R[ 6] += g*b; R[ 7] += g*a; R[10] += b*b; R[11] += b*a; R[15] += a*a; } R[4]=R[1]; R[8]=R[2]; R[9]=R[6]; R[12]=R[3]; R[13]=R[7]; R[14]=R[11]; return {R:R, m:m, N:N}; } UPNG.quantize.estats = function(stats){ var R = stats.R, m = stats.m, N = stats.N; // when all samples are equal, but N is large (millions), the Rj can be non-zero ( 0.0003.... - precission error) var m0 = m[0], m1 = m[1], m2 = m[2], m3 = m[3], iN = (N==0 ? 0 : 1/N); var Rj = [ R[ 0] - m0*m0*iN, R[ 1] - m0*m1*iN, R[ 2] - m0*m2*iN, R[ 3] - m0*m3*iN, R[ 4] - m1*m0*iN, R[ 5] - m1*m1*iN, R[ 6] - m1*m2*iN, R[ 7] - m1*m3*iN, R[ 8] - m2*m0*iN, R[ 9] - m2*m1*iN, R[10] - m2*m2*iN, R[11] - m2*m3*iN, R[12] - m3*m0*iN, R[13] - m3*m1*iN, R[14] - m3*m2*iN, R[15] - m3*m3*iN ]; var A = Rj, M = UPNG.M4; var b = [Math.random(),Math.random(),Math.random(),Math.random()], mi = 0, tmi = 0; if(N!=0) for(var i=0; i<16; i++) { b = M.multVec(A, b); tmi = Math.sqrt(M.dot(b,b)); b = M.sml(1/tmi, b); if(i!=0 && Math.abs(tmi-mi)<1e-9) break; mi = tmi; } //b = [0,0,1,0]; mi=N; var q = [m0*iN, m1*iN, m2*iN, m3*iN]; var eMq255 = M.dot(M.sml(255,q),b); return { Cov:Rj, q:q, e:b, L:mi, eMq255:eMq255, eMq : M.dot(b,q), rgba: (((Math.round(255*q[3])<<24) | (Math.round(255*q[2])<<16) | (Math.round(255*q[1])<<8) | (Math.round(255*q[0])<<0))>>>0) }; } UPNG.M4 = { multVec : function(m,v) { return [ m[ 0]*v[0] + m[ 1]*v[1] + m[ 2]*v[2] + m[ 3]*v[3], m[ 4]*v[0] + m[ 5]*v[1] + m[ 6]*v[2] + m[ 7]*v[3], m[ 8]*v[0] + m[ 9]*v[1] + m[10]*v[2] + m[11]*v[3], m[12]*v[0] + m[13]*v[1] + m[14]*v[2] + m[15]*v[3] ]; }, dot : function(x,y) { return x[0]*y[0]+x[1]*y[1]+x[2]*y[2]+x[3]*y[3]; }, sml : function(a,y) { return [a*y[0],a*y[1],a*y[2],a*y[3]]; } } UPNG.encode.concatRGBA = function(bufs) { var tlen = 0; for(var i=0; i<bufs.length; i++) tlen += bufs[i].byteLength; var nimg = new Uint8Array(tlen), noff=0; for(var i=0; i<bufs.length; i++) { var img = new Uint8Array(bufs[i]), il = img.length; for(var j=0; j<il; j+=4) { var r=img[j], g=img[j+1], b=img[j+2], a = img[j+3]; if(a==0) r=g=b=0; nimg[noff+j]=r; nimg[noff+j+1]=g; nimg[noff+j+2]=b; nimg[noff+j+3]=a; } noff += il; } return nimg.buffer; } UPNG.encode.dither = function(sb, w, h, plte, tb, oind) { function addErr(er, tg, ti, f) { tg[ti]+=(er[0]*f)>>4; tg[ti+1]+=(er[1]*f)>>4; tg[ti+2]+=(er[2]*f)>>4; tg[ti+3]+=(er[3]*f)>>4; } function N(x) { return Math.max(0, Math.min(255, x)); } function D(a,b) { var dr=a[0]-b[0], dg=a[1]-b[1], db=a[2]-b[2], da=a[3]-b[3]; return (dr*dr + dg*dg + db*db + da*da); } var pc=plte.length, nplt = [], rads=[]; for(var i=0; i<pc; i++) { var c = plte[i]; nplt.push([((c>>>0)&255), ((c>>>8)&255), ((c>>>16)&255), ((c>>>24)&255)]); } for(var i=0; i<pc; i++) { var ne=0xffffffff, ni=0; for(var j=0; j<pc; j++) { var ce=D(nplt[i],nplt[j]); if(j!=i && ce<ne) { ne=ce; ni=j; } } var hd = Math.sqrt(ne)/2; rads[i] = ~~(hd*hd); } var tb32 = new Uint32Array(tb.buffer); var err = new Int16Array(w*h*4); for(var y=0; y<h; y++) { for(var x=0; x<w; x++) { var i = (y*w+x)*4; var cc = [N(sb[i]+err[i]), N(sb[i+1]+err[i+1]), N(sb[i+2]+err[i+2]), N(sb[i+3]+err[i+3])]; var ni=0, nd = 0xffffff; for(var j=0; j<pc; j++) { var cd = D(cc,nplt[j]); if(cd<nd) { nd=cd; ni=j; } } //ni = oind[i>>2]; var nc = nplt[ni]; var er = [cc[0]-nc[0], cc[1]-nc[1], cc[2]-nc[2], cc[3]-nc[3]]; //addErr(er, err, i+4, 16); //* if(x!=w-1) addErr(er, err, i+4 , 7); if(y!=h-1) { if(x!= 0) addErr(er, err, i+4*w-4, 3); addErr(er, err, i+4*w , 5); if(x!=w-1) addErr(er, err, i+4*w+4, 1); //*/ } oind[i>>2] = ni; tb32[i>>2] = plte[ni]; } } }