{"version":3,"sources":["jsdelivr-header.js","/npm/png-js@1.0.0/png.js"],"names":[],"mappings":"AAAA;AACA;AACA;AACA;AACA;AACA;AACA,ACcA,OAAO,IAAM,WACX,IAKI,EAAgB,SAAS,cAAc,UACvC,EAAa,EAAc,WAAW,MACtC,EAAY,SAAS,GACvB,EAAW,MAAQ,EAAU,MAC7B,EAAW,OAAS,EAAU,OAC9B,EAAW,UAAU,EAAG,EAAG,EAAU,MAAO,EAAU,QACtD,EAAW,aAAa,EAAW,EAAG,GAEtC,MAAM,EAAM,IAAI,MAEhB,OADA,EAAI,IAAM,EAAc,YACjB,CACT,EAEA,MAAM,EACJ,WAAO,CAAK,EAAK,EAAQ,GACD,mBAAX,IACT,EAAW,GAGb,MAAM,EAAM,IAAI,eAYhB,OAXA,EAAI,KAAK,MAAO,GAAK,GACrB,EAAI,aAAe,cACnB,EAAI,OAAS,KACX,MAAM,EAAO,IAAI,WAAW,EAAI,UAAY,EAAI,wBAC1C,EAAM,IAAI,EAAI,GAIpB,MAH6C,mBAAjC,GAAU,EAAO,aAC3B,EAAI,OAAO,GAEc,mBAAb,EAA0B,EAAS,QAAO,CAAS,EAG5D,EAAI,KAAK,KAClB,CAEA,WAAA,CAAY,GACV,IAAI,EACJ,KAAK,KAAO,EACZ,KAAK,IAAM,EAEX,KAAK,QAAU,GACf,KAAK,QAAU,GACf,KAAK,aAAe,CAAC,EACrB,KAAK,UAAY,KACjB,KAAK,KAAO,CAAC,EACb,IAAI,EAAQ,KAEZ,OAAa,CACX,IAAI,EACJ,IAAI,EAAY,KAAK,aACjB,EAAU,GACd,IAAK,EAAI,EAAG,EAAI,EAAG,IACjB,GAAW,OAAO,aAAa,KAAK,KAAK,KAAK,QAGhD,OAAQ,GACN,IAAK,OAEH,KAAK,MAAQ,KAAK,aAClB,KAAK,OAAS,KAAK,aACnB,KAAK,KAAO,KAAK,KAAK,KAAK,OAC3B,KAAK,UAAY,KAAK,KAAK,KAAK,OAChC,KAAK,kBAAoB,KAAK,KAAK,KAAK,OACxC,KAAK,aAAe,KAAK,KAAK,KAAK,OACnC,KAAK,gBAAkB,KAAK,KAAK,KAAK,OACtC,MAEF,IAAK,OAEH,KAAK,UAAY,CACf,UAAW,KAAK,aAChB,SAAU,KAAK,cAAgB,IAC/B,OAAQ,IAEV,MAEF,IAAK,OACH,KAAK,QAAU,KAAK,KAAK,GACzB,MAEF,IAAK,OACC,GACF,KAAK,UAAU,OAAO,KAAK,GAG7B,KAAK,KAAO,EACZ,EAAQ,CACN,MAAO,KAAK,aACZ,OAAQ,KAAK,aACb,QAAS,KAAK,aACd,QAAS,KAAK,cAGhB,IAAI,EAAW,KAAK,aAChB,EAAW,KAAK,cAAgB,IACpC,EAAM,MAAS,IAAO,EAAY,EAElC,EAAM,UAAY,KAAK,KAAK,KAAK,OACjC,EAAM,QAAU,KAAK,KAAK,KAAK,OAC/B,EAAM,KAAO,GACb,MAEF,IAAK,OACL,IAAK,OAOH,IANgB,SAAZ,IACF,KAAK,KAAO,EACZ,GAAa,GAGf,EAAQ,GAAS,EAAM,MAAS,KAAK,QAChC,EAAI,EAAG,EAAI,EAAW,IACzB,EAAK,KAAK,KAAK,KAAK,KAAK,QAE3B,MAEF,IAAK,OAIH,OADA,KAAK,aAAe,CAAC,EACb,KAAK,WACX,KAAK,EAKH,KAAK,aAAa,QAAU,KAAK,KAAK,GACtC,IAAI,EAAQ,IAAM,KAAK,aAAa,QAAQ,OAC5C,GAAI,EAAQ,EACV,IAAK,EAAI,EAAG,EAAI,EAAO,IACrB,KAAK,aAAa,QAAQ,KAAK,KAGnC,MACF,KAAK,EAGH,KAAK,aAAa,UAAY,KAAK,KAAK,GAAW,GACnD,MACF,KAAK,EAEH,KAAK,aAAa,IAAM,KAAK,KAAK,GAGtC,MAEF,IAAK,OACH,IAAI,EAAO,KAAK,KAAK,GACjB,EAAQ,EAAK,QAAQ,GACrB,EAAM,OAAO,aAAa,MAAM,OAAQ,EAAK,MAAM,EAAG,IAC1D,KAAK,KAAK,GAAO,OAAO,aAAa,MACnC,OACA,EAAK,MAAM,EAAQ,IAErB,MAEF,IAAK,OAMH,OALI,GACF,KAAK,UAAU,OAAO,KAAK,GAIrB,KAAK,WACX,KAAK,EACL,KAAK,EACL,KAAK,EACH,KAAK,OAAS,EACd,MACF,KAAK,EACL,KAAK,EACH,KAAK,OAAS,EAIlB,KAAK,gBAAkB,CAAC,EAAG,GAAG,SAAS,KAAK,WAC5C,IAAI,EAAS,KAAK,QAAU,KAAK,gBAAkB,EAAI,GAGvD,OAFA,KAAK,eAAiB,KAAK,KAAO,EAE1B,KAAK,QACX,KAAK,EACH,KAAK,WAAa,aAClB,MACF,KAAK,EACH,KAAK,WAAa,YAKtB,YADA,KAAK,QAAU,IAAI,WAAW,KAAK,UAIrC,QAEE,KAAK,KAAO,EAKhB,GAFA,KAAK,KAAO,EAER,KAAK,IAAM,KAAK,KAAK,OACvB,MAAM,IAAI,MAAM,iCAEpB,CACF,CAEA,IAAA,CAAK,GACH,MAAM,EAAS,IAAI,MAAM,GACzB,IAAK,IAAI,EAAI,EAAG,EAAI,EAAO,IACzB,EAAO,GAAK,KAAK,KAAK,KAAK,OAE7B,OAAO,CACT,CAEA,UAAA,GAKE,OAJW,KAAK,KAAK,KAAK,QAAU,GACzB,KAAK,KAAK,KAAK,QAAU,GACzB,KAAK,KAAK,KAAK,QAAU,EACzB,KAAK,KAAK,KAAK,MAE5B,CAEA,UAAA,GAGE,OAFW,KAAK,KAAK,KAAK,QAAU,EACzB,KAAK,KAAK,KAAK,MAE5B,CAEA,YAAA,CAAa,GAIX,GAHY,MAAR,IACF,EAAO,KAAK,SAEM,IAAhB,EAAK,OACP,OAAO,IAAI,WAAW,GAIxB,GADA,EAAO,IAAI,YAAY,IACX,WAEZ,MAAM,MAAE,EAAK,OAAE,GAAW,KACpB,EAAa,KAAK,eAAiB,EAEnC,EAAS,IAAI,WAAW,EAAQ,EAAS,IACzC,OAAE,GAAW,EACnB,IAAI,EAAM,EAEV,SAAS,EAAK,EAAI,EAAI,EAAI,EAAI,GAAa,GACzC,MAAM,EAAI,KAAK,MAAM,EAAQ,GAAM,GAC7B,EAAI,KAAK,MAAM,EAAS,GAAM,GAC9B,EAAiB,EAAa,EAC9B,EAAS,EAAa,EAAS,IAAI,WAAW,EAAiB,GACrE,IAAI,EAAM,EACN,EAAI,EACR,KAAO,EAAM,GAAK,EAAM,GAAQ,CAC9B,IAAI,EAAM,EAAK,EAAG,EAAM,EACxB,OAAQ,EAAK,MACX,KAAK,EACH,IAAK,EAAI,EAAG,EAAI,EAAgB,IAC9B,EAAO,KAAO,EAAK,KAErB,MAEF,KAAK,EACH,IAAK,EAAI,EAAG,EAAI,EAAgB,IAC9B,EAAO,EAAK,KACZ,EAAO,EAAI,EAAa,EAAI,EAAO,EAAI,GACvC,EAAO,MAAQ,EAAO,GAAQ,IAEhC,MAEF,KAAK,EACH,IAAK,EAAI,EAAG,EAAI,EAAgB,IAC9B,EAAO,EAAK,KACZ,GAAO,EAAK,EAAI,GAAe,EAC/B,EACE,GACA,GACG,EAAM,GAAK,EACV,EAAM,EACL,EAAI,GAEX,EAAO,MAAQ,EAAQ,GAAQ,IAEjC,MAEF,KAAK,EACH,IAAK,EAAI,EAAG,EAAI,EAAgB,IAC9B,EAAO,EAAK,KACZ,GAAO,EAAK,EAAI,GAAe,EAC/B,EAAO,EAAI,EAAa,EAAI,EAAO,EAAI,GACvC,EACE,GACA,GACG,EAAM,GAAK,EACV,EAAM,EACL,EAAI,GAEX,EAAO,MAAQ,EAAO,KAAK,OAAO,EAAO,GAAS,IAAM,IAE1D,MAEF,KAAK,EACH,IAAK,EAAI,EAAG,EAAI,EAAgB,IAAK,CACnC,IAAI,EAAO,EACX,EAAO,EAAK,KACZ,GAAO,EAAK,EAAI,GAAe,EAC/B,EAAO,EAAI,EAAa,EAAI,EAAO,EAAI,GAE3B,IAAR,EACF,EAAQ,EAAY,GAEpB,EACE,GACG,EAAM,GAAK,EACV,EAAM,EACL,EAAI,GAEX,EACE,GACA,GACG,EAAM,GAAK,GACT,EAAM,GAAK,EACX,EAAI,IAIb,MAAM,EAAI,EAAO,EAAQ,EACnB,EAAK,KAAK,IAAI,EAAI,GAClB,EAAK,KAAK,IAAI,EAAI,GAClB,EAAK,KAAK,IAAI,EAAI,GAGtB,EADE,GAAM,GAAM,GAAM,EACZ,EACC,GAAM,EACP,EAEA,EAGV,EAAO,MAAQ,EAAO,GAAS,GACjC,CACA,MAEF,QACE,MAAM,IAAI,MAAM,6BAA6B,EAAK,EAAM,MAG5D,IAAK,EAAY,CACf,IAAI,IAAc,EAAK,EAAM,GAAM,EAAQ,GAAM,EAC7C,EAAY,EAAM,EACtB,IAAK,EAAI,EAAG,EAAI,EAAG,IAAK,CACtB,IAAK,IAAI,EAAI,EAAG,EAAI,EAAY,IAC9B,EAAO,KAAe,EAAO,KAC/B,IAAc,EAAK,GAAK,CAC1B,CACF,CAEA,GACF,CACF,CAwBA,OAtB6B,IAAzB,KAAK,iBAWP,EAAK,EAAG,EAAG,EAAG,GACd,EAAK,EAAG,EAAG,EAAG,GACd,EAAK,EAAG,EAAG,EAAG,GACd,EAAK,EAAG,EAAG,EAAG,GACd,EAAK,EAAG,EAAG,EAAG,GACd,EAAK,EAAG,EAAG,EAAG,GACd,EAAK,EAAG,EAAG,EAAG,IAEd,EAAK,EAAG,EAAG,EAAG,GAAG,GAGZ,CACT,CAEA,aAAA,GACE,MAAM,QAAE,GAAY,MACd,OAAE,GAAW,EACb,EAAe,KAAK,aAAa,SAAW,GAC5C,EAAM,IAAI,YAAY,EAAa,QAAU,GAAK,GACxD,IAAI,EAAM,EACN,EAAI,EAER,IAAK,IAAI,EAAI,EAAG,EAAI,EAAQ,GAAK,EAAG,CAClC,IAAI,EACJ,EAAI,KAAS,EAAQ,GACrB,EAAI,KAAS,EAAQ,EAAI,GACzB,EAAI,KAAS,EAAQ,EAAI,GACzB,EAAI,KAAuC,OAA7B,EAAO,EAAa,MAAgB,EAAO,GAC3D,CAEA,OAAO,CACT,CAEA,eAAA,CAAgB,EAAW,GACzB,IAAI,EAAG,GACH,OAAE,GAAW,KACb,EAAU,KACV,EAAQ,KAAK,gBAEb,KAAK,QAAQ,SACf,EACE,KAAK,kBAAoB,KAAK,gBAAkB,KAAK,iBACvD,EAAS,EACT,GAAQ,GAGV,MAAM,EAAO,EAAU,MAAQ,GACzB,OAAE,GAAW,EACb,EAAQ,GAAW,EACzB,IAAI,EAAK,EAAI,EAEb,GAAe,IAAX,EACF,KAAO,EAAI,GAAQ,CACjB,EAAI,EAA0B,EAAhB,EAAO,EAAI,GAAS,EAClC,MAAM,EAAI,EAAM,KAChB,EAAK,KAAO,EACZ,EAAK,KAAO,EACZ,EAAK,KAAO,EACZ,EAAK,KAAO,EAAQ,EAAM,KAAO,IACjC,EAAI,CACN,MAEA,KAAO,EAAI,GACT,EAAI,EAA0B,EAAhB,EAAO,EAAI,GAAS,EAClC,EAAK,KAAO,EAAM,KAClB,EAAK,KAAO,EAAM,KAClB,EAAK,KAAO,EAAM,KAClB,EAAK,KAAO,EAAQ,EAAM,KAAO,IACjC,EAAI,CAGV,CAEA,MAAA,GACE,MAAM,EAAM,IAAI,WAAW,KAAK,MAAQ,KAAK,OAAS,GAEtD,OADA,KAAK,gBAAgB,EAAK,KAAK,gBACxB,CACT,CAEA,YAAA,CAAa,GACX,GAAK,KAAK,UAIV,IAAK,IAAI,EAAI,EAAG,EAAI,KAAK,UAAU,OAAO,OAAQ,IAAK,CACrD,MAAM,EAAQ,KAAK,UAAU,OAAO,GAC9B,EAAY,EAAI,gBAAgB,EAAM,MAAO,EAAM,QACnD,EAAS,KAAK,aAAa,IAAI,WAAW,EAAM,OAEtD,KAAK,gBAAgB,EAAW,GAChC,EAAM,UAAY,EAClB,EAAM,MAAQ,EAAU,EAC1B,CACF,CAEA,WAAA,CAAY,EAAK,GACf,MAAM,OAAE,GAAW,KAAK,UAClB,EAAQ,EAAO,GACf,EAAO,EAAO,EAAS,GAoB7B,OAjBe,IAAX,GACF,EAAI,UAAU,EAAG,EAAG,KAAK,MAAO,KAAK,QA1dV,KA8dxB,GAAQ,EAAK,WAChB,EAAI,UAAU,EAAK,QAAS,EAAK,QAAS,EAAK,MAAO,EAAK,QA9dlC,KA+df,GAAQ,EAAK,YACvB,EAAI,aAAa,EAAK,UAAW,EAAK,QAAS,EAAK,SA/d/B,IAmenB,EAAM,SACR,EAAI,UAAU,EAAM,QAAS,EAAM,QAAS,EAAM,MAAO,EAAM,QAI1D,EAAI,UAAU,EAAM,MAAO,EAAM,QAAS,EAAM,QACzD,CAEA,OAAA,CAAQ,GACN,IAAI,EAAc,EAClB,MAAM,UAAE,EAAS,OAAE,EAAM,SAAE,GAAa,KAAK,UAEvC,EAAU,KACd,MAAM,EAAI,IAAgB,EACpB,EAAQ,EAAO,GACrB,KAAK,YAAY,EAAK,GAElB,EAAY,GAAK,EAAc,EAAY,IAC7C,KAAK,UAAU,SAAW,WAAW,EAAS,EAAM,OACtD,EAGF,GACF,CAEA,aAAA,GACE,OAAO,aAAa,KAAK,WAAa,KAAK,UAAU,SACvD,CAEA,MAAA,CAAO,GAGD,EAAO,MACT,EAAO,KAAK,gBAGd,EAAO,KAAO,KACd,EAAO,MAAQ,KAAK,MACpB,EAAO,OAAS,KAAK,OACrB,MAAM,EAAM,EAAO,WAAW,MAE9B,GAAI,KAAK,UAEP,OADA,KAAK,aAAa,GACX,KAAK,QAAQ,GACf,CACL,MAAM,EAAO,EAAI,gBAAgB,KAAK,MAAO,KAAK,QAElD,OADA,KAAK,gBAAgB,EAAM,KAAK,gBACzB,EAAI,aAAa,EAAM,EAAG,EACnC,CACF,EAEF,OAAO,CACR,CA3hBY","file":"/npm/png-js@1.0.0/png.js","sourceRoot":"","sourcesContent":["/**\n * Minified by jsDelivr using Terser v5.37.0.\n * Original file: /npm/png-js@1.0.0/png.js\n *\n * Do NOT use SRI with dynamically generated files! More information: https://www.jsdelivr.com/using-sri-with-dynamic-files\n */\n","/*\n * MIT LICENSE\n * Copyright (c) 2011 Devon Govett\n *\n * Permission is hereby granted, free of charge, to any person obtaining a copy of this\n * software and associated documentation files (the \"Software\"), to deal in the Software\n * without restriction, including without limitation the rights to use, copy, modify, merge,\n * publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons\n * to whom the Software is furnished to do so, subject to the following conditions:\n *\n * The above copyright notice and this permission notice shall be included in all copies or\n * substantial portions of the Software.\n *\n * THE SOFTWARE IS PROVIDED \"AS IS\", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING\n * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND\n * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,\n * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,\n * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.\n */\n\nwindow.PNG = (function() {\n let APNG_DISPOSE_OP_NONE = 0;\n let APNG_DISPOSE_OP_BACKGROUND = 1;\n let APNG_DISPOSE_OP_PREVIOUS = 2;\n let APNG_BLEND_OP_SOURCE = 0;\n let APNG_BLEND_OP_OVER = 1;\n let scratchCanvas = document.createElement('canvas');\n let scratchCtx = scratchCanvas.getContext('2d');\n let makeImage = function(imageData) {\n scratchCtx.width = imageData.width;\n scratchCtx.height = imageData.height;\n scratchCtx.clearRect(0, 0, imageData.width, imageData.height);\n scratchCtx.putImageData(imageData, 0, 0);\n\n const img = new Image();\n img.src = scratchCanvas.toDataURL();\n return img;\n };\n\n class PNG {\n static load(url, canvas, callback) {\n if (typeof canvas === 'function') {\n callback = canvas;\n }\n\n const xhr = new XMLHttpRequest();\n xhr.open('GET', url, true);\n xhr.responseType = 'arraybuffer';\n xhr.onload = () => {\n const data = new Uint8Array(xhr.response || xhr.mozResponseArrayBuffer);\n const png = new PNG(data);\n if (typeof (canvas && canvas.getContext) === 'function') {\n png.render(canvas);\n }\n return typeof callback === 'function' ? callback(png) : undefined;\n };\n\n return xhr.send(null);\n }\n\n constructor(data1) {\n let i;\n this.data = data1;\n this.pos = 8; // Skip the default header\n\n this.palette = [];\n this.imgData = [];\n this.transparency = {};\n this.animation = null;\n this.text = {};\n let frame = null;\n\n while (true) {\n var data;\n let chunkSize = this.readUInt32();\n let section = '';\n for (i = 0; i < 4; i++) {\n section += String.fromCharCode(this.data[this.pos++]);\n }\n\n switch (section) {\n case 'IHDR':\n // we can grab interesting values from here (like width, height, etc)\n this.width = this.readUInt32();\n this.height = this.readUInt32();\n this.bits = this.data[this.pos++];\n this.colorType = this.data[this.pos++];\n this.compressionMethod = this.data[this.pos++];\n this.filterMethod = this.data[this.pos++];\n this.interlaceMethod = this.data[this.pos++];\n break;\n\n case 'acTL':\n // we have an animated PNG\n this.animation = {\n numFrames: this.readUInt32(),\n numPlays: this.readUInt32() || Infinity,\n frames: []\n };\n break;\n\n case 'PLTE':\n this.palette = this.read(chunkSize);\n break;\n\n case 'fcTL':\n if (frame) {\n this.animation.frames.push(frame);\n }\n\n this.pos += 4; // skip sequence number\n frame = {\n width: this.readUInt32(),\n height: this.readUInt32(),\n xOffset: this.readUInt32(),\n yOffset: this.readUInt32()\n };\n\n var delayNum = this.readUInt16();\n var delayDen = this.readUInt16() || 100;\n frame.delay = (1000 * delayNum) / delayDen;\n\n frame.disposeOp = this.data[this.pos++];\n frame.blendOp = this.data[this.pos++];\n frame.data = [];\n break;\n\n case 'IDAT':\n case 'fdAT':\n if (section === 'fdAT') {\n this.pos += 4; // skip sequence number\n chunkSize -= 4;\n }\n\n data = (frame && frame.data) || this.imgData;\n for (i = 0; i < chunkSize; i++) {\n data.push(this.data[this.pos++]);\n }\n break;\n\n case 'tRNS':\n // This chunk can only occur once and it must occur after the\n // PLTE chunk and before the IDAT chunk.\n this.transparency = {};\n switch (this.colorType) {\n case 3:\n // Indexed color, RGB. Each byte in this chunk is an alpha for\n // the palette index in the PLTE (\"palette\") chunk up until the\n // last non-opaque entry. Set up an array, stretching over all\n // palette entries which will be 0 (opaque) or 1 (transparent).\n this.transparency.indexed = this.read(chunkSize);\n var short = 255 - this.transparency.indexed.length;\n if (short > 0) {\n for (i = 0; i < short; i++) {\n this.transparency.indexed.push(255);\n }\n }\n break;\n case 0:\n // Greyscale. Corresponding to entries in the PLTE chunk.\n // Grey is two bytes, range 0 .. (2 ^ bit-depth) - 1\n this.transparency.grayscale = this.read(chunkSize)[0];\n break;\n case 2:\n // True color with proper alpha channel.\n this.transparency.rgb = this.read(chunkSize);\n break;\n }\n break;\n\n case 'tEXt':\n var text = this.read(chunkSize);\n var index = text.indexOf(0);\n var key = String.fromCharCode.apply(String, text.slice(0, index));\n this.text[key] = String.fromCharCode.apply(\n String,\n text.slice(index + 1)\n );\n break;\n\n case 'IEND':\n if (frame) {\n this.animation.frames.push(frame);\n }\n\n // we've got everything we need!\n switch (this.colorType) {\n case 0:\n case 3:\n case 4:\n this.colors = 1;\n break;\n case 2:\n case 6:\n this.colors = 3;\n break;\n }\n\n this.hasAlphaChannel = [4, 6].includes(this.colorType);\n var colors = this.colors + (this.hasAlphaChannel ? 1 : 0);\n this.pixelBitlength = this.bits * colors;\n\n switch (this.colors) {\n case 1:\n this.colorSpace = 'DeviceGray';\n break;\n case 3:\n this.colorSpace = 'DeviceRGB';\n break;\n }\n\n this.imgData = new Uint8Array(this.imgData);\n return;\n break;\n\n default:\n // unknown (or unimportant) section, skip it\n this.pos += chunkSize;\n }\n\n this.pos += 4; // Skip the CRC\n\n if (this.pos > this.data.length) {\n throw new Error('Incomplete or corrupt PNG file');\n }\n }\n }\n\n read(bytes) {\n const result = new Array(bytes);\n for (let i = 0; i < bytes; i++) {\n result[i] = this.data[this.pos++];\n }\n return result;\n }\n\n readUInt32() {\n const b1 = this.data[this.pos++] << 24;\n const b2 = this.data[this.pos++] << 16;\n const b3 = this.data[this.pos++] << 8;\n const b4 = this.data[this.pos++];\n return b1 | b2 | b3 | b4;\n }\n\n readUInt16() {\n const b1 = this.data[this.pos++] << 8;\n const b2 = this.data[this.pos++];\n return b1 | b2;\n }\n\n decodePixels(data) {\n if (data == null) {\n data = this.imgData;\n }\n if (data.length === 0) {\n return new Uint8Array(0);\n }\n\n data = new FlateStream(data);\n data = data.getBytes();\n\n const { width, height } = this;\n const pixelBytes = this.pixelBitlength / 8;\n\n const pixels = new Uint8Array(width * height * pixelBytes);\n const { length } = data;\n let pos = 0;\n\n function pass(x0, y0, dx, dy, singlePass = false) {\n const w = Math.ceil((width - x0) / dx);\n const h = Math.ceil((height - y0) / dy);\n const scanlineLength = pixelBytes * w;\n const buffer = singlePass ? pixels : new Uint8Array(scanlineLength * h);\n let row = 0;\n let c = 0;\n while (row < h && pos < length) {\n var byte, col, i, left, upper;\n switch (data[pos++]) {\n case 0: // None\n for (i = 0; i < scanlineLength; i++) {\n buffer[c++] = data[pos++];\n }\n break;\n\n case 1: // Sub\n for (i = 0; i < scanlineLength; i++) {\n byte = data[pos++];\n left = i < pixelBytes ? 0 : buffer[c - pixelBytes];\n buffer[c++] = (byte + left) % 256;\n }\n break;\n\n case 2: // Up\n for (i = 0; i < scanlineLength; i++) {\n byte = data[pos++];\n col = (i - (i % pixelBytes)) / pixelBytes;\n upper =\n row &&\n buffer[\n (row - 1) * scanlineLength +\n col * pixelBytes +\n (i % pixelBytes)\n ];\n buffer[c++] = (upper + byte) % 256;\n }\n break;\n\n case 3: // Average\n for (i = 0; i < scanlineLength; i++) {\n byte = data[pos++];\n col = (i - (i % pixelBytes)) / pixelBytes;\n left = i < pixelBytes ? 0 : buffer[c - pixelBytes];\n upper =\n row &&\n buffer[\n (row - 1) * scanlineLength +\n col * pixelBytes +\n (i % pixelBytes)\n ];\n buffer[c++] = (byte + Math.floor((left + upper) / 2)) % 256;\n }\n break;\n\n case 4: // Paeth\n for (i = 0; i < scanlineLength; i++) {\n var paeth, upperLeft;\n byte = data[pos++];\n col = (i - (i % pixelBytes)) / pixelBytes;\n left = i < pixelBytes ? 0 : buffer[c - pixelBytes];\n\n if (row === 0) {\n upper = upperLeft = 0;\n } else {\n upper =\n buffer[\n (row - 1) * scanlineLength +\n col * pixelBytes +\n (i % pixelBytes)\n ];\n upperLeft =\n col &&\n buffer[\n (row - 1) * scanlineLength +\n (col - 1) * pixelBytes +\n (i % pixelBytes)\n ];\n }\n\n const p = left + upper - upperLeft;\n const pa = Math.abs(p - left);\n const pb = Math.abs(p - upper);\n const pc = Math.abs(p - upperLeft);\n\n if (pa <= pb && pa <= pc) {\n paeth = left;\n } else if (pb <= pc) {\n paeth = upper;\n } else {\n paeth = upperLeft;\n }\n\n buffer[c++] = (byte + paeth) % 256;\n }\n break;\n\n default:\n throw new Error(`Invalid filter algorithm: ${data[pos - 1]}`);\n }\n\n if (!singlePass) {\n let pixelsPos = ((y0 + row * dy) * width + x0) * pixelBytes;\n let bufferPos = row * scanlineLength;\n for (i = 0; i < w; i++) {\n for (let j = 0; j < pixelBytes; j++)\n pixels[pixelsPos++] = buffer[bufferPos++];\n pixelsPos += (dx - 1) * pixelBytes;\n }\n }\n\n row++;\n }\n }\n\n if (this.interlaceMethod === 1) {\n /*\n 1 6 4 6 2 6 4 6\n 7 7 7 7 7 7 7 7\n 5 6 5 6 5 6 5 6\n 7 7 7 7 7 7 7 7\n 3 6 4 6 3 6 4 6\n 7 7 7 7 7 7 7 7\n 5 6 5 6 5 6 5 6\n 7 7 7 7 7 7 7 7\n */\n pass(0, 0, 8, 8); // 1\n pass(4, 0, 8, 8); // 2\n pass(0, 4, 4, 8); // 3\n pass(2, 0, 4, 4); // 4\n pass(0, 2, 2, 4); // 5\n pass(1, 0, 2, 2); // 6\n pass(0, 1, 1, 2); // 7\n } else {\n pass(0, 0, 1, 1, true);\n }\n\n return pixels;\n }\n\n decodePalette() {\n const { palette } = this;\n const { length } = palette;\n const transparency = this.transparency.indexed || [];\n const ret = new Uint8Array((transparency.length || 0) + length);\n let pos = 0;\n let c = 0;\n\n for (let i = 0; i < length; i += 3) {\n var left;\n ret[pos++] = palette[i];\n ret[pos++] = palette[i + 1];\n ret[pos++] = palette[i + 2];\n ret[pos++] = (left = transparency[c++]) != null ? left : 255;\n }\n\n return ret;\n }\n\n copyToImageData(imageData, pixels) {\n let j, k;\n let { colors } = this;\n let palette = null;\n let alpha = this.hasAlphaChannel;\n\n if (this.palette.length) {\n palette =\n this._decodedPalette || (this._decodedPalette = this.decodePalette());\n colors = 4;\n alpha = true;\n }\n\n const data = imageData.data || imageData;\n const { length } = data;\n const input = palette || pixels;\n let i = (j = 0);\n\n if (colors === 1) {\n while (i < length) {\n k = palette ? pixels[i / 4] * 4 : j;\n const v = input[k++];\n data[i++] = v;\n data[i++] = v;\n data[i++] = v;\n data[i++] = alpha ? input[k++] : 255;\n j = k;\n }\n } else {\n while (i < length) {\n k = palette ? pixels[i / 4] * 4 : j;\n data[i++] = input[k++];\n data[i++] = input[k++];\n data[i++] = input[k++];\n data[i++] = alpha ? input[k++] : 255;\n j = k;\n }\n }\n }\n\n decode() {\n const ret = new Uint8Array(this.width * this.height * 4);\n this.copyToImageData(ret, this.decodePixels());\n return ret;\n }\n\n decodeFrames(ctx) {\n if (!this.animation) {\n return;\n }\n\n for (let i = 0; i < this.animation.frames.length; i++) {\n const frame = this.animation.frames[i];\n const imageData = ctx.createImageData(frame.width, frame.height);\n const pixels = this.decodePixels(new Uint8Array(frame.data));\n\n this.copyToImageData(imageData, pixels);\n frame.imageData = imageData;\n frame.image = makeImage(imageData);\n }\n }\n\n renderFrame(ctx, number) {\n const { frames } = this.animation;\n const frame = frames[number];\n const prev = frames[number - 1];\n\n // if we're on the first frame, clear the canvas\n if (number === 0) {\n ctx.clearRect(0, 0, this.width, this.height);\n }\n\n // check the previous frame's dispose operation\n if ((prev && prev.disposeOp) === APNG_DISPOSE_OP_BACKGROUND) {\n ctx.clearRect(prev.xOffset, prev.yOffset, prev.width, prev.height);\n } else if ((prev && prev.disposeOp) === APNG_DISPOSE_OP_PREVIOUS) {\n ctx.putImageData(prev.imageData, prev.xOffset, prev.yOffset);\n }\n\n // APNG_BLEND_OP_SOURCE overwrites the previous data\n if (frame.blendOp === APNG_BLEND_OP_SOURCE) {\n ctx.clearRect(frame.xOffset, frame.yOffset, frame.width, frame.height);\n }\n\n // draw the current frame\n return ctx.drawImage(frame.image, frame.xOffset, frame.yOffset);\n }\n\n animate(ctx) {\n let frameNumber = 0;\n const { numFrames, frames, numPlays } = this.animation;\n\n const doFrame = () => {\n const f = frameNumber++ % numFrames;\n const frame = frames[f];\n this.renderFrame(ctx, f);\n\n if (numFrames > 1 && frameNumber / numFrames < numPlays) {\n this.animation._timeout = setTimeout(doFrame, frame.delay);\n }\n };\n\n doFrame();\n }\n\n stopAnimation() {\n return clearTimeout(this.animation && this.animation._timeout);\n }\n\n render(canvas) {\n // if this canvas was displaying another image before,\n // stop the animation on it\n if (canvas._png) {\n canvas._png.stopAnimation();\n }\n\n canvas._png = this;\n canvas.width = this.width;\n canvas.height = this.height;\n const ctx = canvas.getContext('2d');\n\n if (this.animation) {\n this.decodeFrames(ctx);\n return this.animate(ctx);\n } else {\n const data = ctx.createImageData(this.width, this.height);\n this.copyToImageData(data, this.decodePixels());\n return ctx.putImageData(data, 0, 0);\n }\n }\n }\n return PNG;\n})();\n"]}