Lip synchronization is the synchronization of audio signals (sometimes with corresponding video signals) so that there is no noticeable lack of simultaneity between them. The term lip sync is an abbreviation of lip synchronization, and describes two similar forms of vocal pantomime.

One is a form of musical pantomime in which a performer moves his/her lips to the words of a played musical recording, creating the illusion of the performer singing in the recorded singer's voice. The hobby reached its greatest popularity in the 1980s, hitting its peak with the syndicated television game show, Puttin' On The Hits. Professional performers sometimes use this method in live performances, especially in dance numbers that require too much exertion to perform as well as sing. It was once common in the Hong Kong music scene. It can also be used fraudulently to misrepresent a musical act with the group, Milli Vanilli being the most notorious.

The other is the art of making a character appear to speak in a pre-recorded track of dialogue. The lip sync technique to make an animated character appear to speak involves figuring out the timings of the speech (breakdown) as well as the actual animating of the lips/mouth to match the dialogue track. The earliest examples of lip-sync in animation were attempted by Max Fleischer in his 1926 short My Old Kentucky Home. The technique continues to this day, with animated films and television shows such as Shrek, Lilo & Stitch, and The Simpsons using lip-syncing to make their artificial characters talk. Lip synching is also used in comedies such as This Hour Has 22 Minutes and political satire, changing totally or just partially the original wording. It has been used in conjunction with translation of films from one language to another, for example, Spirited Away.

Quality film dubbing requires translating the speech so that the number of syllables in characters' remarks is the same in both languages so that lip syncing is possible (if the character's face is visible on screen).

An example of a lip synchronization problem is the case in which television video and audio signals are transported via different facilities (e.g., a geosynchronous satellite radio link and a landline) that have significantly differently delay times, respectively. In such cases it is necessary to delay the audio electronically to allow for the difference in propagation times.

As character models in computer games became more detailed, it became important to animate their mouths when they speak. In early 2000s it was usually done manually. Half-Life 2 introduced the technology to generate correct lip movements automatically, using the audio file with the speech and the script.

"Famous Singers That Have Been Caught Lip-Synching"

1. Britney Spears
2. Janet Jackson
3. Madonna
4. Lindsay Lohan
5. Ashlee Simpson
6. Milli Vanilli
7. The Backstreet Boys
8. N'Sync
9. Jennifer Lopez
10. Holly Valance
11. Paris Hilton
12. Beyonce Knowles
13. Victoria Beckham
14. Eminem
15. Whitney Houston
16. Shania Twain
17. Mariah Carey

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See also

1. Federal Standard 1037C
2. List of electronics topics

External links

• Lip Sync - Making Characters Speak in 3D
• Lip Sync Videos of old pop songs
• Bush and Blair's "Endless Love" (satirical music video) - Quicktime format