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Diffstat (limited to 'sourcecodes/scripts/canvas-toBlob.js')
| -rw-r--r-- | sourcecodes/scripts/canvas-toBlob.js | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/sourcecodes/scripts/canvas-toBlob.js b/sourcecodes/scripts/canvas-toBlob.js new file mode 100644 index 00000000..3dd3c7ef --- /dev/null +++ b/sourcecodes/scripts/canvas-toBlob.js @@ -0,0 +1,125 @@ +/* canvas-toBlob.js + * A canvas.toBlob() implementation. + * 2016-05-26 + * + * By Eli Grey, http://eligrey.com and Devin Samarin, https://github.com/eboyjr + * License: MIT + * See https://github.com/eligrey/canvas-toBlob.js/blob/master/LICENSE.md + */ + +/*global self */ +/*jslint bitwise: true, regexp: true, confusion: true, es5: true, vars: true, white: true, + plusplus: true */ + +/*! @source http://purl.eligrey.com/github/canvas-toBlob.js/blob/master/canvas-toBlob.js */ + +(function(view) { + "use strict"; +var + Uint8Array = view.Uint8Array + , HTMLCanvasElement = view.HTMLCanvasElement + , canvas_proto = HTMLCanvasElement && HTMLCanvasElement.prototype + , is_base64_regex = /\s*;\s*base64\s*(?:;|$)/i + , to_data_url = "toDataURL" + , base64_ranks + , decode_base64 = function(base64) { + var + len = base64.length + , buffer = new Uint8Array(len / 4 * 3 | 0) + , i = 0 + , outptr = 0 + , last = [0, 0] + , state = 0 + , save = 0 + , rank + , code + , undef + ; + while (len--) { + code = base64.charCodeAt(i++); + rank = base64_ranks[code-43]; + if (rank !== 255 && rank !== undef) { + last[1] = last[0]; + last[0] = code; + save = (save << 6) | rank; + state++; + if (state === 4) { + buffer[outptr++] = save >>> 16; + if (last[1] !== 61 /* padding character */) { + buffer[outptr++] = save >>> 8; + } + if (last[0] !== 61 /* padding character */) { + buffer[outptr++] = save; + } + state = 0; + } + } + } + // 2/3 chance there's going to be some null bytes at the end, but that + // doesn't really matter with most image formats. + // If it somehow matters for you, truncate the buffer up outptr. + return buffer; +} +; +if (Uint8Array) { + base64_ranks = new Uint8Array([ + 62, -1, -1, -1, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1 + , -1, -1, 0, -1, -1, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 + , 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25 + , -1, -1, -1, -1, -1, -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35 + , 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51 + ]); +} +if (HTMLCanvasElement && (!canvas_proto.toBlob || !canvas_proto.toBlobHD)) { + if (!canvas_proto.toBlob) + canvas_proto.toBlob = function(callback, type /*, ...args*/) { + if (!type) { + type = "image/png"; + } if (this.mozGetAsFile) { + callback(this.mozGetAsFile("canvas", type)); + return; + } if (this.msToBlob && /^\s*image\/png\s*(?:$|;)/i.test(type)) { + callback(this.msToBlob()); + return; + } + + var + args = Array.prototype.slice.call(arguments, 1) + , dataURI = this[to_data_url].apply(this, args) + , header_end = dataURI.indexOf(",") + , data = dataURI.substring(header_end + 1) + , is_base64 = is_base64_regex.test(dataURI.substring(0, header_end)) + , blob + ; + if (Blob.fake) { + // no reason to decode a data: URI that's just going to become a data URI again + blob = new Blob + if (is_base64) { + blob.encoding = "base64"; + } else { + blob.encoding = "URI"; + } + blob.data = data; + blob.size = data.length; + } else if (Uint8Array) { + if (is_base64) { + blob = new Blob([decode_base64(data)], {type: type}); + } else { + blob = new Blob([decodeURIComponent(data)], {type: type}); + } + } + callback(blob); + }; + + if (!canvas_proto.toBlobHD && canvas_proto.toDataURLHD) { + canvas_proto.toBlobHD = function() { + to_data_url = "toDataURLHD"; + var blob = this.toBlob(); + to_data_url = "toDataURL"; + return blob; + } + } else { + canvas_proto.toBlobHD = canvas_proto.toBlob; + } +} +}(typeof self !== "undefined" && self || typeof window !== "undefined" && window || this.content || this)); |