Proyectos de Subversion LeadersLinked - Antes de SPA

/* piexifjs

The MIT License (MIT)

Copyright (c) 2014, 2015 hMatoba(https://github.com/hMatoba)

Permission is hereby granted, free of charge, to any person obtaining a copy

of this software and associated documentation files (the "Software"), to deal

in the Software without restriction, including without limitation the rights

to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

copies of the Software, and to permit persons to whom the Software is

furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all

copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE

SOFTWARE.

*/

(function () {

    "use strict";

    var that = {};

    that.version = "1.03";

    that.remove = function (jpeg) {

        var b64 = false;

        if (jpeg.slice(0, 2) == "\xff\xd8") {

        } else if (jpeg.slice(0, 23) == "data:image/jpeg;base64," || jpeg.slice(0, 22) == "data:image/jpg;base64,") {

            jpeg = atob(jpeg.split(",")[1]);

            b64 = true;

        } else {

            throw ("Given data is not jpeg.");

        }

        var segments = splitIntoSegments(jpeg);

        if (segments[1].slice(0, 2) == "\xff\xe1" &&

               segments[1].slice(4, 10) == "Exif\x00\x00") {

            segments = [segments[0]].concat(segments.slice(2));

        } else if (segments[2].slice(0, 2) == "\xff\xe1" &&

                   segments[2].slice(4, 10) == "Exif\x00\x00") {

            segments = segments.slice(0, 2).concat(segments.slice(3));

        } else {

            throw("Exif not found.");

        }

        var new_data = segments.join("");

        if (b64) {

            new_data = "data:image/jpeg;base64," + btoa(new_data);

        }

        return new_data;

    };

    that.insert = function (exif, jpeg) {

        var b64 = false;

        if (exif.slice(0, 6) != "\x45\x78\x69\x66\x00\x00") {

            throw ("Given data is not exif.");

        }

        if (jpeg.slice(0, 2) == "\xff\xd8") {

        } else if (jpeg.slice(0, 23) == "data:image/jpeg;base64," || jpeg.slice(0, 22) == "data:image/jpg;base64,") {

            jpeg = atob(jpeg.split(",")[1]);

            b64 = true;

        } else {

            throw ("Given data is not jpeg.");

        }

        var exifStr = "\xff\xe1" + pack(">H", [exif.length + 2]) + exif;

        var segments = splitIntoSegments(jpeg);

        var new_data = mergeSegments(segments, exifStr);

        if (b64) {

            new_data = "data:image/jpeg;base64," + btoa(new_data);

        }

        return new_data;

    };

    that.load = function (data) {

        var input_data;

        if (typeof (data) == "string") {

            if (data.slice(0, 2) == "\xff\xd8") {

                input_data = data;

            } else if (data.slice(0, 23) == "data:image/jpeg;base64," || data.slice(0, 22) == "data:image/jpg;base64,") {

                input_data = atob(data.split(",")[1]);

            } else if (data.slice(0, 4) == "Exif") {

                input_data = data.slice(6);

            } else {

                throw ("'load' gots invalid file data.");

            }

        } else {

            throw ("'load' gots invalid type argument.");

        }

        var exifDict = {};

        var exif_dict = {

            "0th": {},

            "Exif": {},

            "GPS": {},

            "Interop": {},

            "1st": {},

            "thumbnail": null

        };

        var exifReader = new ExifReader(input_data);

        if (exifReader.tiftag === null) {

            return exif_dict;

        }

        if (exifReader.tiftag.slice(0, 2) == "\x49\x49") {

            exifReader.endian_mark = "<";

        } else {

            exifReader.endian_mark = ">";

        }

        var pointer = unpack(exifReader.endian_mark + "L",

            exifReader.tiftag.slice(4, 8))[0];

        exif_dict["0th"] = exifReader.get_ifd(pointer, "0th");

        var first_ifd_pointer = exif_dict["0th"]["first_ifd_pointer"];

        delete exif_dict["0th"]["first_ifd_pointer"];

        if (34665 in exif_dict["0th"]) {

            pointer = exif_dict["0th"][34665];

            exif_dict["Exif"] = exifReader.get_ifd(pointer, "Exif");

        }

        if (34853 in exif_dict["0th"]) {

            pointer = exif_dict["0th"][34853];

            exif_dict["GPS"] = exifReader.get_ifd(pointer, "GPS");

        }

        if (40965 in exif_dict["Exif"]) {

            pointer = exif_dict["Exif"][40965];

            exif_dict["Interop"] = exifReader.get_ifd(pointer, "Interop");

        }

        if (first_ifd_pointer != "\x00\x00\x00\x00") {

            pointer = unpack(exifReader.endian_mark + "L",

                first_ifd_pointer)[0];

            exif_dict["1st"] = exifReader.get_ifd(pointer, "1st");

            if ((513 in exif_dict["1st"]) && (514 in exif_dict["1st"])) {

                var end = exif_dict["1st"][513] + exif_dict["1st"][514];

                var thumb = exifReader.tiftag.slice(exif_dict["1st"][513], end);

                exif_dict["thumbnail"] = thumb;

            }

        }

        return exif_dict;

    };

    that.dump = function (exif_dict_original) {

        var TIFF_HEADER_LENGTH = 8;

        var exif_dict = copy(exif_dict_original);

        var header = "Exif\x00\x00\x4d\x4d\x00\x2a\x00\x00\x00\x08";

        var exif_is = false;

        var gps_is = false;

        var interop_is = false;

        var first_is = false;

        var zeroth_ifd,

            exif_ifd,

            interop_ifd,

            gps_ifd,

            first_ifd;

        if ("0th" in exif_dict) {

            zeroth_ifd = exif_dict["0th"];

        } else {

            zeroth_ifd = {};

        }

        if ((("Exif" in exif_dict) && (Object.keys(exif_dict["Exif"]).length)) ||

            (("Interop" in exif_dict) && (Object.keys(exif_dict["Interop"]).length))) {

            zeroth_ifd[34665] = 1;

            exif_is = true;

            exif_ifd = exif_dict["Exif"];

            if (("Interop" in exif_dict) && Object.keys(exif_dict["Interop"]).length) {

                exif_ifd[40965] = 1;

                interop_is = true;

                interop_ifd = exif_dict["Interop"];

            } else if (Object.keys(exif_ifd).indexOf(that.ExifIFD.InteroperabilityTag.toString()) > -1) {

                delete exif_ifd[40965];

            }

        } else if (Object.keys(zeroth_ifd).indexOf(that.ImageIFD.ExifTag.toString()) > -1) {

            delete zeroth_ifd[34665];

        }

        if (("GPS" in exif_dict) && (Object.keys(exif_dict["GPS"]).length)) {

            zeroth_ifd[that.ImageIFD.GPSTag] = 1;

            gps_is = true;

            gps_ifd = exif_dict["GPS"];

        } else if (Object.keys(zeroth_ifd).indexOf(that.ImageIFD.GPSTag.toString()) > -1) {

            delete zeroth_ifd[that.ImageIFD.GPSTag];

        }

        if (("1st" in exif_dict) &&

            ("thumbnail" in exif_dict) &&

            (exif_dict["thumbnail"] != null)) {

            first_is = true;

            exif_dict["1st"][513] = 1;

            exif_dict["1st"][514] = 1;

            first_ifd = exif_dict["1st"];

        }

        var zeroth_set = _dict_to_bytes(zeroth_ifd, "0th", 0);

        var zeroth_length = (zeroth_set[0].length + exif_is * 12 + gps_is * 12 + 4 +

            zeroth_set[1].length);

        var exif_set,

            exif_bytes = "",

            exif_length = 0,

            gps_set,

            gps_bytes = "",

            gps_length = 0,

            interop_set,

            interop_bytes = "",

            interop_length = 0,

            first_set,

            first_bytes = "",

            thumbnail;

        if (exif_is) {

            exif_set = _dict_to_bytes(exif_ifd, "Exif", zeroth_length);

            exif_length = exif_set[0].length + interop_is * 12 + exif_set[1].length;

        }

        if (gps_is) {

            gps_set = _dict_to_bytes(gps_ifd, "GPS", zeroth_length + exif_length);

            gps_bytes = gps_set.join("");

            gps_length = gps_bytes.length;

        }

        if (interop_is) {

            var offset = zeroth_length + exif_length + gps_length;

            interop_set = _dict_to_bytes(interop_ifd, "Interop", offset);

            interop_bytes = interop_set.join("");

            interop_length = interop_bytes.length;

        }

        if (first_is) {

            var offset = zeroth_length + exif_length + gps_length + interop_length;

            first_set = _dict_to_bytes(first_ifd, "1st", offset);

            thumbnail = _get_thumbnail(exif_dict["thumbnail"]);

            if (thumbnail.length > 64000) {

                throw ("Given thumbnail is too large. max 64kB");

            }

        }

        var exif_pointer = "",

            gps_pointer = "",

            interop_pointer = "",

            first_ifd_pointer = "\x00\x00\x00\x00";

        if (exif_is) {

            var pointer_value = TIFF_HEADER_LENGTH + zeroth_length;

            var pointer_str = pack(">L", [pointer_value]);

            var key = 34665;

            var key_str = pack(">H", [key]);

            var type_str = pack(">H", [TYPES["Long"]]);

            var length_str = pack(">L", [1]);

            exif_pointer = key_str + type_str + length_str + pointer_str;

        }

        if (gps_is) {

            var pointer_value = TIFF_HEADER_LENGTH + zeroth_length + exif_length;

            var pointer_str = pack(">L", [pointer_value]);

            var key = 34853;

            var key_str = pack(">H", [key]);

            var type_str = pack(">H", [TYPES["Long"]]);

            var length_str = pack(">L", [1]);

            gps_pointer = key_str + type_str + length_str + pointer_str;

        }

        if (interop_is) {

            var pointer_value = (TIFF_HEADER_LENGTH +

                zeroth_length + exif_length + gps_length);

            var pointer_str = pack(">L", [pointer_value]);

            var key = 40965;

            var key_str = pack(">H", [key]);

            var type_str = pack(">H", [TYPES["Long"]]);

            var length_str = pack(">L", [1]);

            interop_pointer = key_str + type_str + length_str + pointer_str;

        }

        if (first_is) {

            var pointer_value = (TIFF_HEADER_LENGTH + zeroth_length +

                exif_length + gps_length + interop_length);

            first_ifd_pointer = pack(">L", [pointer_value]);

            var thumbnail_pointer = (pointer_value + first_set[0].length + 24 +

                4 + first_set[1].length);

            var thumbnail_p_bytes = ("\x02\x01\x00\x04\x00\x00\x00\x01" +

                pack(">L", [thumbnail_pointer]));

            var thumbnail_length_bytes = ("\x02\x02\x00\x04\x00\x00\x00\x01" +

                pack(">L", [thumbnail.length]));

            first_bytes = (first_set[0] + thumbnail_p_bytes +

                thumbnail_length_bytes + "\x00\x00\x00\x00" +

                first_set[1] + thumbnail);

        }

        var zeroth_bytes = (zeroth_set[0] + exif_pointer + gps_pointer +

            first_ifd_pointer + zeroth_set[1]);

        if (exif_is) {

            exif_bytes = exif_set[0] + interop_pointer + exif_set[1];

        }

        return (header + zeroth_bytes + exif_bytes + gps_bytes +

            interop_bytes + first_bytes);

    };

    function copy(obj) {

        return JSON.parse(JSON.stringify(obj));

    }

    function _get_thumbnail(jpeg) {

        var segments = splitIntoSegments(jpeg);

        while (("\xff\xe0" <= segments[1].slice(0, 2)) && (segments[1].slice(0, 2) <= "\xff\xef")) {

            segments = [segments[0]].concat(segments.slice(2));

        }

        return segments.join("");

    }

    function _pack_byte(array) {

        return pack(">" + nStr("B", array.length), array);

    }

    function _pack_short(array) {

        return pack(">" + nStr("H", array.length), array);

    }

    function _pack_long(array) {

        return pack(">" + nStr("L", array.length), array);

    }

    function _value_to_bytes(raw_value, value_type, offset) {

        var four_bytes_over = "";

        var value_str = "";

        var length,

            new_value,

            num,

            den;

        if (value_type == "Byte") {

            length = raw_value.length;

            if (length <= 4) {

                value_str = (_pack_byte(raw_value) +

                    nStr("\x00", 4 - length));

            } else {

                value_str = pack(">L", [offset]);

                four_bytes_over = _pack_byte(raw_value);

            }

        } else if (value_type == "Short") {

            length = raw_value.length;

            if (length <= 2) {

                value_str = (_pack_short(raw_value) +

                    nStr("\x00\x00", 2 - length));

            } else {

                value_str = pack(">L", [offset]);

                four_bytes_over = _pack_short(raw_value);

            }

        } else if (value_type == "Long") {

            length = raw_value.length;

            if (length <= 1) {

                value_str = _pack_long(raw_value);

            } else {

                value_str = pack(">L", [offset]);

                four_bytes_over = _pack_long(raw_value);

            }

        } else if (value_type == "Ascii") {

            new_value = raw_value + "\x00";

            length = new_value.length;

            if (length > 4) {

                value_str = pack(">L", [offset]);

                four_bytes_over = new_value;

            } else {

                value_str = new_value + nStr("\x00", 4 - length);

            }

        } else if (value_type == "Rational") {

            if (typeof (raw_value[0]) == "number") {

                length = 1;

                num = raw_value[0];

                den = raw_value[1];

                new_value = pack(">L", [num]) + pack(">L", [den]);

            } else {

                length = raw_value.length;

                new_value = "";

                for (var n = 0; n < length; n++) {

                    num = raw_value[n][0];

                    den = raw_value[n][1];

                    new_value += (pack(">L", [num]) +

                        pack(">L", [den]));

                }

            }

            value_str = pack(">L", [offset]);

            four_bytes_over = new_value;

        } else if (value_type == "SRational") {

            if (typeof (raw_value[0]) == "number") {

                length = 1;

                num = raw_value[0];

                den = raw_value[1];

                new_value = pack(">l", [num]) + pack(">l", [den]);

            } else {

                length = raw_value.length;

                new_value = "";

                for (var n = 0; n < length; n++) {

                    num = raw_value[n][0];

                    den = raw_value[n][1];

                    new_value += (pack(">l", [num]) +

                        pack(">l", [den]));

                }

            }

            value_str = pack(">L", [offset]);

            four_bytes_over = new_value;

        } else if (value_type == "Undefined") {

            length = raw_value.length;

            if (length > 4) {

                value_str = pack(">L", [offset]);

                four_bytes_over = raw_value;

            } else {

                value_str = raw_value + nStr("\x00", 4 - length);

            }

        }

        var length_str = pack(">L", [length]);

        return [length_str, value_str, four_bytes_over];

    }

    function _dict_to_bytes(ifd_dict, ifd, ifd_offset) {

        var TIFF_HEADER_LENGTH = 8;

        var tag_count = Object.keys(ifd_dict).length;

        var entry_header = pack(">H", [tag_count]);

        var entries_length;

        if (["0th", "1st"].indexOf(ifd) > -1) {

            entries_length = 2 + tag_count * 12 + 4;

        } else {

            entries_length = 2 + tag_count * 12;

        }

        var entries = "";

        var values = "";

        var key;

        for (var key in ifd_dict) {

            if (typeof (key) == "string") {

                key = parseInt(key);

            }

            if ((ifd == "0th") && ([34665, 34853].indexOf(key) > -1)) {

                continue;

            } else if ((ifd == "Exif") && (key == 40965)) {

                continue;

            } else if ((ifd == "1st") && ([513, 514].indexOf(key) > -1)) {

                continue;

            }

            var raw_value = ifd_dict[key];

            var key_str = pack(">H", [key]);

            var value_type = TAGS[ifd][key]["type"];

            var type_str = pack(">H", [TYPES[value_type]]);

            if (typeof (raw_value) == "number") {

                raw_value = [raw_value];

            }

            var offset = TIFF_HEADER_LENGTH + entries_length + ifd_offset + values.length;

            var b = _value_to_bytes(raw_value, value_type, offset);

            var length_str = b[0];

            var value_str = b[1];

            var four_bytes_over = b[2];

            entries += key_str + type_str + length_str + value_str;

            values += four_bytes_over;

        }

        return [entry_header + entries, values];

    }

    function ExifReader(data) {

        var segments,

            app1;

        if (data.slice(0, 2) == "\xff\xd8") { // JPEG

            segments = splitIntoSegments(data);

            app1 = getExifSeg(segments);

            if (app1) {

                this.tiftag = app1.slice(10);

            } else {

                this.tiftag = null;

            }

        } else if (["\x49\x49", "\x4d\x4d"].indexOf(data.slice(0, 2)) > -1) { // TIFF

            this.tiftag = data;

        } else if (data.slice(0, 4) == "Exif") { // Exif

            this.tiftag = data.slice(6);

        } else {

            throw ("Given file is neither JPEG nor TIFF.");

        }

    }

    ExifReader.prototype = {

        get_ifd: function (pointer, ifd_name) {

            var ifd_dict = {};

            var tag_count = unpack(this.endian_mark + "H",

                this.tiftag.slice(pointer, pointer + 2))[0];

            var offset = pointer + 2;

            var t;

            if (["0th", "1st"].indexOf(ifd_name) > -1) {

                t = "Image";

            } else {

                t = ifd_name;

            }

            for (var x = 0; x < tag_count; x++) {

                pointer = offset + 12 * x;

                var tag = unpack(this.endian_mark + "H",

                    this.tiftag.slice(pointer, pointer + 2))[0];

                var value_type = unpack(this.endian_mark + "H",

                    this.tiftag.slice(pointer + 2, pointer + 4))[0];

                var value_num = unpack(this.endian_mark + "L",

                    this.tiftag.slice(pointer + 4, pointer + 8))[0];

                var value = this.tiftag.slice(pointer + 8, pointer + 12);

                var v_set = [value_type, value_num, value];

                if (tag in TAGS[t]) {

                    ifd_dict[tag] = this.convert_value(v_set);

                }

            }

            if (ifd_name == "0th") {

                pointer = offset + 12 * tag_count;

                ifd_dict["first_ifd_pointer"] = this.tiftag.slice(pointer, pointer + 4);

            }

            return ifd_dict;

        },

        convert_value: function (val) {

            var data = null;

            var t = val[0];

            var length = val[1];

            var value = val[2];

            var pointer;

            if (t == 1) { // BYTE

                if (length > 4) {

                    pointer = unpack(this.endian_mark + "L", value)[0];

                    data = unpack(this.endian_mark + nStr("B", length),

                        this.tiftag.slice(pointer, pointer + length));

                } else {

                    data = unpack(this.endian_mark + nStr("B", length), value.slice(0, length));

                }

            } else if (t == 2) { // ASCII

                if (length > 4) {

                    pointer = unpack(this.endian_mark + "L", value)[0];

                    data = this.tiftag.slice(pointer, pointer + length - 1);

                } else {

                    data = value.slice(0, length - 1);

                }

            } else if (t == 3) { // SHORT

                if (length > 2) {

                    pointer = unpack(this.endian_mark + "L", value)[0];

                    data = unpack(this.endian_mark + nStr("H", length),

                        this.tiftag.slice(pointer, pointer + length * 2));

                } else {

                    data = unpack(this.endian_mark + nStr("H", length),

                        value.slice(0, length * 2));

                }

            } else if (t == 4) { // LONG

                if (length > 1) {

                    pointer = unpack(this.endian_mark + "L", value)[0];

                    data = unpack(this.endian_mark + nStr("L", length),

                        this.tiftag.slice(pointer, pointer + length * 4));

                } else {

                    data = unpack(this.endian_mark + nStr("L", length),

                        value);

                }

            } else if (t == 5) { // RATIONAL

                pointer = unpack(this.endian_mark + "L", value)[0];

                if (length > 1) {

                    data = [];

                    for (var x = 0; x < length; x++) {

                        data.push([unpack(this.endian_mark + "L",

                                this.tiftag.slice(pointer + x * 8, pointer + 4 + x * 8))[0],

                                   unpack(this.endian_mark + "L",

                                this.tiftag.slice(pointer + 4 + x * 8, pointer + 8 + x * 8))[0]

                                   ]);

                    }

                } else {

                    data = [unpack(this.endian_mark + "L",

                            this.tiftag.slice(pointer, pointer + 4))[0],

                            unpack(this.endian_mark + "L",

                            this.tiftag.slice(pointer + 4, pointer + 8))[0]

                            ];

                }

            } else if (t == 7) { // UNDEFINED BYTES

                if (length > 4) {

                    pointer = unpack(this.endian_mark + "L", value)[0];

                    data = this.tiftag.slice(pointer, pointer + length);

                } else {

                    data = value.slice(0, length);

                }

            } else if (t == 10) { // SRATIONAL

                pointer = unpack(this.endian_mark + "L", value)[0];

                if (length > 1) {

                    data = [];

                    for (var x = 0; x < length; x++) {

                        data.push([unpack(this.endian_mark + "l",

                                this.tiftag.slice(pointer + x * 8, pointer + 4 + x * 8))[0],

                                   unpack(this.endian_mark + "l",

                                this.tiftag.slice(pointer + 4 + x * 8, pointer + 8 + x * 8))[0]

                                  ]);

                    }

                } else {

                    data = [unpack(this.endian_mark + "l",

                            this.tiftag.slice(pointer, pointer + 4))[0],

                            unpack(this.endian_mark + "l",

                            this.tiftag.slice(pointer + 4, pointer + 8))[0]

                           ];

                }

            } else {

                throw ("Exif might be wrong. Got incorrect value " +

                    "type to decode. type:" + t);

            }

            if ((data instanceof Array) && (data.length == 1)) {

                return data[0];

            } else {

                return data;

            }

        },

    };

    if (typeof window !== "undefined" && typeof window.btoa === "function") {

        var btoa = window.btoa;

    }

    if (typeof btoa === "undefined") {

        var btoa = function (input) {        var output = "";

            var chr1, chr2, chr3, enc1, enc2, enc3, enc4;

            var i = 0;

            var keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";

            while (i < input.length) {

                chr1 = input.charCodeAt(i++);

                chr2 = input.charCodeAt(i++);

                chr3 = input.charCodeAt(i++);

                enc1 = chr1 >> 2;

                enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);

                enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);

                enc4 = chr3 & 63;

                if (isNaN(chr2)) {

                    enc3 = enc4 = 64;

                } else if (isNaN(chr3)) {

                    enc4 = 64;

                }

                output = output +

                keyStr.charAt(enc1) + keyStr.charAt(enc2) +

                keyStr.charAt(enc3) + keyStr.charAt(enc4);

            }

            return output;

        };

    }

    if (typeof window !== "undefined" && typeof window.atob === "function") {

        var atob = window.atob;

    }

    if (typeof atob === "undefined") {

        var atob = function (input) {

            var output = "";

            var chr1, chr2, chr3;

            var enc1, enc2, enc3, enc4;

            var i = 0;

            var keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";

            input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");

            while (i < input.length) {

                enc1 = keyStr.indexOf(input.charAt(i++));

                enc2 = keyStr.indexOf(input.charAt(i++));

                enc3 = keyStr.indexOf(input.charAt(i++));

                enc4 = keyStr.indexOf(input.charAt(i++));

                chr1 = (enc1 << 2) | (enc2 >> 4);

                chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);

                chr3 = ((enc3 & 3) << 6) | enc4;

                output = output + String.fromCharCode(chr1);

                if (enc3 != 64) {

                    output = output + String.fromCharCode(chr2);

                }

                if (enc4 != 64) {

                    output = output + String.fromCharCode(chr3);

                }

            }

            return output;

        };

    }

    function getImageSize(imageArray) {

        var segments = slice2Segments(imageArray);

        var seg,

            width,

            height,

            SOF = [192, 193, 194, 195, 197, 198, 199, 201, 202, 203, 205, 206, 207];

        for (var x = 0; x < segments.length; x++) {

            seg = segments[x];

            if (SOF.indexOf(seg[1]) >= 0) {

                height = seg[5] * 256 + seg[6];

                width = seg[7] * 256 + seg[8];

                break;

            }

        }

        return [width, height];

    }

    function pack(mark, array) {

        if (!(array instanceof Array)) {

            throw ("'pack' error. Got invalid type argument.");

        }

        if ((mark.length - 1) != array.length) {

            throw ("'pack' error. " + (mark.length - 1) + " marks, " + array.length + " elements.");

        }

        var littleEndian;

        if (mark[0] == "<") {

            littleEndian = true;

        } else if (mark[0] == ">") {

            littleEndian = false;

        } else {

            throw ("");

        }

        var packed = "";

        var p = 1;

        var val = null;

        var c = null;

        var valStr = null;

        while (c = mark[p]) {

            if (c.toLowerCase() == "b") {

                val = array[p - 1];

                if ((c == "b") && (val < 0)) {

                    val += 0x100;

                }

                if ((val > 0xff) || (val < 0)) {

                    throw ("'pack' error.");

                } else {

                    valStr = String.fromCharCode(val);

                }

            } else if (c == "H") {

                val = array[p - 1];

                if ((val > 0xffff) || (val < 0)) {

                    throw ("'pack' error.");

                } else {

                    valStr = String.fromCharCode(Math.floor((val % 0x10000) / 0x100)) +

                        String.fromCharCode(val % 0x100);

                    if (littleEndian) {

                        valStr = valStr.split("").reverse().join("");

                    }

                }

            } else if (c.toLowerCase() == "l") {

                val = array[p - 1];

                if ((c == "l") && (val < 0)) {

                    val += 0x100000000;

                }

                if ((val > 0xffffffff) || (val < 0)) {

                    throw ("'pack' error.");

                } else {

                    valStr = String.fromCharCode(Math.floor(val / 0x1000000)) +

                        String.fromCharCode(Math.floor((val % 0x1000000) / 0x10000)) +

                        String.fromCharCode(Math.floor((val % 0x10000) / 0x100)) +

                        String.fromCharCode(val % 0x100);

                    if (littleEndian) {

                        valStr = valStr.split("").reverse().join("");

                    }

                }

            } else {

                throw ("'pack' error.");

            }

            packed += valStr;

            p += 1;

        }

        return packed;

    }

    function unpack(mark, str) {

        if (typeof (str) != "string") {

            throw ("'unpack' error. Got invalid type argument.");

        }

        var l = 0;

        for (var markPointer = 1; markPointer < mark.length; markPointer++) {

            if (mark[markPointer].toLowerCase() == "b") {

                l += 1;

            } else if (mark[markPointer].toLowerCase() == "h") {

                l += 2;

            } else if (mark[markPointer].toLowerCase() == "l") {

                l += 4;

            } else {

                throw ("'unpack' error. Got invalid mark.");

            }

        }

        if (l != str.length) {

            throw ("'unpack' error. Mismatch between symbol and string length. " + l + ":" + str.length);

        }

        var littleEndian;

        if (mark[0] == "<") {

            littleEndian = true;

        } else if (mark[0] == ">") {

            littleEndian = false;

        } else {

            throw ("'unpack' error.");

        }

        var unpacked = [];

        var strPointer = 0;

        var p = 1;

        var val = null;

        var c = null;

        var length = null;

        var sliced = "";

        while (c = mark[p]) {

            if (c.toLowerCase() == "b") {

                length = 1;

                sliced = str.slice(strPointer, strPointer + length);

                val = sliced.charCodeAt(0);

                if ((c == "b") && (val >= 0x80)) {

                    val -= 0x100;

                }

            } else if (c == "H") {

                length = 2;

                sliced = str.slice(strPointer, strPointer + length);

                if (littleEndian) {

                    sliced = sliced.split("").reverse().join("");

                }

                val = sliced.charCodeAt(0) * 0x100 +

                    sliced.charCodeAt(1);

            } else if (c.toLowerCase() == "l") {

                length = 4;

                sliced = str.slice(strPointer, strPointer + length);

                if (littleEndian) {

                    sliced = sliced.split("").reverse().join("");

                }

                val = sliced.charCodeAt(0) * 0x1000000 +

                    sliced.charCodeAt(1) * 0x10000 +

                    sliced.charCodeAt(2) * 0x100 +

                    sliced.charCodeAt(3);

                if ((c == "l") && (val >= 0x80000000)) {

                    val -= 0x100000000;

                }

            } else {

                throw ("'unpack' error. " + c);

            }

            unpacked.push(val);

            strPointer += length;

            p += 1;

        }

        return unpacked;

    }

    function nStr(ch, num) {

        var str = "";

        for (var i = 0; i < num; i++) {

            str += ch;

        }

        return str;

    }

    function splitIntoSegments(data) {

        if (data.slice(0, 2) != "\xff\xd8") {

            throw ("Given data isn't JPEG.");

        }

        var head = 2;

        var segments = ["\xff\xd8"];

        while (true) {

            if (data.slice(head, head + 2) == "\xff\xda") {

                segments.push(data.slice(head));

                break;

            } else {

                var length = unpack(">H", data.slice(head + 2, head + 4))[0];

                var endPoint = head + length + 2;

                segments.push(data.slice(head, endPoint));

                head = endPoint;

            }

            if (head >= data.length) {

                throw ("Wrong JPEG data.");

            }

        }

        return segments;

    }

    function getExifSeg(segments) {

        var seg;

        for (var i = 0; i < segments.length; i++) {

            seg = segments[i];

            if (seg.slice(0, 2) == "\xff\xe1" &&

                   seg.slice(4, 10) == "Exif\x00\x00") {

                return seg;

            }

        }

        return null;

    }

    function mergeSegments(segments, exif) {

        if (segments[1].slice(0, 2) == "\xff\xe0" &&

            (segments[2].slice(0, 2) == "\xff\xe1" &&

             segments[2].slice(4, 10) == "Exif\x00\x00")) {

            if (exif) {

                segments[2] = exif;

                segments = ["\xff\xd8"].concat(segments.slice(2));

            } else if (exif == null) {

                segments = segments.slice(0, 2).concat(segments.slice(3));

            } else {

                segments = segments.slice(0).concat(segments.slice(2));

            }

        } else if (segments[1].slice(0, 2) == "\xff\xe0") {

            if (exif) {

                segments[1] = exif;

            }

        } else if (segments[1].slice(0, 2) == "\xff\xe1" &&

                   segments[1].slice(4, 10) == "Exif\x00\x00") {

            if (exif) {

                segments[1] = exif;

            } else if (exif == null) {

                segments = segments.slice(0).concat(segments.slice(2));

            }

        } else {

            if (exif) {

                segments = [segments[0], exif].concat(segments.slice(1));

            }

        }

        return segments.join("");

    }

    function toHex(str) {

        var hexStr = "";

        for (var i = 0; i < str.length; i++) {

            var h = str.charCodeAt(i);

            var hex = ((h < 10) ? "0" : "") + h.toString(16);

            hexStr += hex + " ";

        }

        return hexStr;

    }

    var TYPES = {

        "Byte": 1,

        "Ascii": 2,

        "Short": 3,

        "Long": 4,

        "Rational": 5,

        "Undefined": 7,

        "SLong": 9,

        "SRational": 10

    };

    var TAGS = {

        'Image': {

            11: {

                'name': 'ProcessingSoftware',

                'type': 'Ascii'

            },

            254: {

                'name': 'NewSubfileType',

                'type': 'Long'

            },

            255: {

                'name': 'SubfileType',

                'type': 'Short'

            },

            256: {

                'name': 'ImageWidth',

                'type': 'Long'

            },

            257: {

                'name': 'ImageLength',