<h4>Serialisability of script execution</h4>

<p>A string is a <dfn>valid normalised local date and time string</dfn> representing a date and

time if it consists of the following components in the given order:</p>

<h4>Colours</h4>

<p>A <dfn>simple colour</dfn> consists of three 8-bit numbers in the range 0..255, representing the

red, green, and blue components of the colour respectively, in the sRGB colour space. <ref spec=SRGB></p>

<p>A string is a <dfn>valid simple colour</dfn> if it is exactly seven characters long, and the

first character is a U+0023 NUMBER SIGN character (#), and the remaining six characters are all

<span>ASCII hex digits</span>, with the first two digits representing the red component, the

middle two digits representing the green component, and the last two digits representing the blue

component, in hexadecimal.</p>

<p>A string is a <dfn>valid lowercase simple colour</dfn> if it is a <span>valid simple

colour</span> and doesn't use any characters in the range U+0041 LATIN CAPITAL LETTER A to U+0046

LATIN CAPITAL LETTER F.</p>

<p>The <dfn>rules for parsing simple colour values</dfn> are as given in the following algorithm.

When invoked, the steps must be followed in the order given, aborting at the first step that

returns a value. This algorithm will return either a <span>simple colour</span> or an error.</p>

<p>The <dfn>rules for serialising simple colour values</dfn> given a <span>simple colour</span> are

as given in the following algorithm:</p>

<p>Some obsolete legacy attributes parse colours in a more complicated manner, using the <dfn>rules

for parsing a legacy colour value</dfn>, which are given in the following algorithm. When invoked,

the steps must be followed in the order given, aborting at the first step that returns a value.

This algorithm will return either a <span>simple colour</span> or an error.</p>

data-noexport="">reinitialise url</dfn> algorithm, which runs these steps:</p>

<p>When asked to <dfn>normalise the source densities</dfn> of a <span>source set</span> <var>source set</var>,

the user agent must do the following:</p>

<p>When a <code>TimeRanges</code> object is said to be a <dfn>normalised <code>TimeRanges</code>

object</dfn>, the ranges it represents must obey the following criteria:</p>

<span>task source</span> for this task is the <dfn>canvas blob serialisation task

source</dfn>.</p></li>

<p>The <dfn>serialisation of a colour</dfn> for a colour value is a string, computed as follows: if

it has alpha equal to 1.0, then the string is a lowercase six-digit hex value, prefixed with a "#"

character (U+0023 NUMBER SIGN), with the first two digits representing the red component, the next

two digits representing the green component, and the last two digits representing the blue

component, the digits being <span>lowercase ASCII hex digits</span>. Otherwise, the colour value

has alpha less than 1.0, and the string is the colour value in the CSS <code data-x="">rgba()</code>

functional-notation format: the literal string "<code data-x="">rgba</code>" (U+0072 U+0067 U+0062

U+0061) followed by a U+0028 LEFT PARENTHESIS, a base-ten integer in the range 0-255 representing

the red component (using <span>ASCII digits</span> in the shortest form possible), a literal

U+002C COMMA and U+0020 SPACE, an integer for the green component, a comma and a space, an integer

for the blue component, another comma and space, a U+0030 DIGIT ZERO, if the alpha value is

greater than zero then a U+002E FULL STOP (representing the decimal point), if the alpha value is

greater than zero then one or more <span>ASCII digits</span> representing the fractional part of

the alpha<!-- value with no trailing zeros (implied by next sentence)-->, and finally a U+0029

RIGHT PARENTHESIS. User agents must express the fractional part of the alpha value, if any, with

the level of precision necessary for the alpha value, when reparsed, to be interpreted as the same

alpha value.</p> <!-- if people complain this is unreadable, expand it into a <dl> with two nested

<ol>s -->

<h5>Colour spaces and colour correction</h5>

<h5>Serialising bitmaps to a file</h5>

<p>When a user agent is to create <dfn>a serialisation of the bitmap as a file</dfn>, given an

optional <var>type</var> and <var>quality</var>, it must create an image file in the format given

by <var>type</var>, or if <var>type</var> was not supplied, in the PNG format. <ref spec=PNG></p>

the <dfn>activation behaviour</dfn> defined for that element, if any. Activation behaviours can

refer to the <code data-x="event-click">click</code> event that was fired by the steps above

leading up to this point.</p>

<p>The <dfn data-export="">Unicode serialisation of an origin</dfn> is the string obtained by

applying the following algorithm to the given <span>origin</span> <var>origin</var>:</p>

<p>The <dfn data-export="">ASCII serialisation of an origin</dfn> is the string obtained by

applying the following algorithm to the given <span>origin</span> <var>origin</var>:</p>

<p><dfn data-x="initialise the Document object" data-export="">Initialising a new

<code>Document</code> object</dfn>: when a <code>Document</code> is created as part of the above

steps, the user agent will be required to additionally run the following algorithm after

creating the new object:</p>

<p>The <dfn>timer initialisation steps</dfn>, which are invoked with some method arguments, a <var>method context</var>, a <var>repeat</var> flag which can be true or false, and

optionally (and only if the <var>repeat</var> flag is true) a <var>previous

<h3>Serialising HTML fragments</h3>

<p>The following steps form the <dfn>HTML fragment serialisation algorithm</dfn>. The algorithm

takes as input a DOM <code>Element</code>, <code>Document</code>, or <code>DocumentFragment</code>

referred to as <var>the node</var>, and returns a string.</p>

<p>An <dfn>attribute's serialised name</dfn> for the purposes of the previous paragraph must

be determined as follows:</p>

<h3>Serialising XHTML fragments</h3>

<p>The <dfn>XML fragment serialisation algorithm</dfn> for a <code>Document</code> or

<code>Element</code> node either returns a fragment of XML that represents that node or throws an

exception.</p>

<h4>The <code>input</code> element as a colour well</h4>

<p>The <dfn>frame border colour</dfn> of a <code>frameset</code> or <code>frame</code> element

is the colour obtained from the following algorithm:</p>