Implementation of emojis

Today, the exact appearance of emoji is not prescribed but can vary between fonts and platforms, much like different typefaces.

[1] Different computing companies have developed their own fonts to display emoji, some of which have been open-sourced to permit their reuse.

[4] Various, often incompatible, character encoding schemes were developed by the different mobile providers in Japan for their own emoji sets.

When transmitted in Shift JIS on NTT DoCoMo, emoji symbols are specified as a two-byte sequence in the range F89F through F9FC (as expressed in hexadecimal).

[12] UCS-2 is now obsolete and deprecated in favour of UTF-16, a variable-width encoding which follows UCS-2 for the BMP, but extends it with four-byte codes representing non-BMP characters.

[12] For example, earlier versions of MySQL supported UCS-2 and a variant of UTF-8 excluding four-byte codes, thus not handling non-BMP characters correctly.

[15] The introduction of Unicode emoji created an incentive for vendors to improve their support for non-BMP characters.

Not all operating systems have support for color fonts, so in these cases emoji might have to be rendered as black-and-white line art or not at all.

[32] However, mobile phone vendors HTC and LG deployed variants of NotoColorEmoji.ttf with custom glyphs prior to 2017,[33] and Samsung still does.

[34] Some Japanese mobile carriers used to equip branded Android devices with emoji glyphs that were closer to the original ones, but apparently have stopped updating these circa 2015.

[clarification needed] Apple first introduced emoji to their desktop operating system with the release of OS X 10.7 Lion, in 2011.

[41] Optionally, the Fn key alone can be specified by the user in the keyboard preferences menu to bring up the Character Viewer.

Apple has revealed that the "face with tears of joy" is the most popular emoji among English speaking Americans.

[44][45] On September 12, 2017, Apple announced that the Messages app on the iPhones with Face ID would get "Animoji", which are versions of standard emoji that are custom-animated with the use of facial motion capture to reflect the sender's expressions.

These Animoji can also utilize lip sync to appear to speak audio messages recorded by the sender.

Apple had created 3D models of all standard emoji prior to its late-2016 OS updates from which the static default 2D graphics had been rendered.

With the release of iOS 12, Apple introduced "Memoji" that allows the use of an avatar that a user can use to personalize messages; this feature does not require Face ID.

[citation needed] As part of the now-discontinued Firefox OS project, Mozilla developed an emoji font named FxEmojis.

[65] As of Windows 8.1 Preview, the Segoe UI Emoji font is included, which supplies full-color pictographs.

[66] Microsoft's COLR/CPAL format for multi-color fonts such as Segoe UI Emoji is supported by the current versions of several web browsers on Windows (including Firefox, Google Chrome, Internet Explorer and Microsoft Edge), but not by many graphics applications.

[citation needed] Facebook and Twitter replace all Unicode emoji used on their websites with their own custom graphics.

Prior to October 2017, Facebook had different sets for the main site and for its Messenger service, where only the former provides complete coverage.