Formats Supported by QuickTime

QuickTime supports a lot of media formats and codecs, with many more coming all the time. Some examples of formats and codecs supported by QuickTime follow.

Movie File Formats

File formats are the overarching structure used to store data. Different movie file formats place video and audio media in different parts of the file, as well as the associated metadata. The most commonly used media file formats supported by QuickTime are described below.

AVI

AVI, or Audio Video Interleave, is a PC-compatible standard for digital video. This file type is no longer officially supported by Microsoft, but it’s still frequently used. The AVI format supports fewer codecs than QuickTime for video and audio and is mainly useful for Windows delivery of video for multimedia use.

DV Stream

DV Stream files multiplex audio and video together digitally on a DV videotape. These files are primarily for use with iMovie. Final Cut Pro converts DV streams to QuickTime movies with independent video and audio tracks during capture.

MPEG-2

MPEG-2 is a video standard used for modern digital video format, including digital television broadcast and DVD.

MPEG-4

MPEG-4 is an open standard video format intended for cross-platform, Internet, and multimedia delivery of video and audio content.

QuickTime Movie

This is a general-purpose media format that can contain multiple video, audio, text, and other tracks. This is the native file format used by Final Cut Pro for capturing and export.

Video Codecs Supported Within Video File Formats

A video codec is an algorithm for encoding video images in space (within a frame) and time (across multiple frames) to compress the data requirements while still producing an acceptable image. Not all codecs are supported by all file formats.

Uncompressed (None)

This isn’t really a codec, but a way of storing QuickTime movies with no compression at all. Since applying compression generally results in video artifacts, no compression guarantees the highest quality. Unfortunately, it also guarantees enormous file sizes, and they will not play back in real time on most systems.

Uncompressed movies can have an alpha channel. Alpha channels define levels of transparency in your movie and are useful if you’re delivering an effects shot for use in someone else’s composition. For more information on alpha channels, see Compositing and Layering.

Animation

The Animation codec was developed for computer-generated imagery, which often has large areas of uniform color and little, if any, noise. It is a lossless codec, which means it doesn’t degrade quality or add artifacts to your video when it applies compression. For more information, see Video Compression.

Video footage, which generally has more grain, noise, and variations of texture and color than animated material, may not be compressed as much with the Animation codec as with other methods. Because some lossless compression is better than none, this codec is used more frequently than Uncompressed.

Note: Animation movies will not play back in real time on most systems. Animation movies can also have an alpha channel.

DV Codecs

QuickTime supports a wide range of DV codecs, including DV NTSC and DV PAL, DVCPRO 50, and DVCPRO HD. This allows you to natively capture, edit, and play back footage from DV camcorders without first transcoding to another format.

Apple M-JPEG

There are two Apple M-JPEG codecs, M-JPEG A and M-JPEG B. These are variable data rate codecs similar to the ones used by video capture cards. If you need to deliver more heavily compressed material to keep files small, consider these codecs. M-JPEG is a “lossy” codec (meaning visual information is permanently removed from the video frames) and will result in artifacts in your video. The severity of these artifacts depends on the data rate you choose.

Several video interface cards on the market can play back either M-JPEG A or M-JPEG B in real time without rerendering the material, or, at most, doing minimal rerendering. This makes file interchange very fast. Before you use either M-JPEG A or B, consult the manufacturer of the capture card you’re using to find out which one you should use.

Note: Apple M-JPEG movies cannot have alpha channels.

JPEG

JPEG is similar to M-JPEG, except that the compression artifacts can be less severe at similar data rates. JPEG movies may play back in real time on your system, depending on your system’s capabilities and the data rate of the movie.

Note: JPEG movies cannot have alpha channels.

Third-Party Codecs

There are several manufacturers of video-editing solutions, most of whom use different variations of the M-JPEG codec. Many make software-only QuickTime codecs that you can install on your system, enabling you to play back movies with little or no rerendering. For more information, contact the manufacturer of the editing system.

Note: Most third-party codecs cannot have alpha channels.

Graphics and Still-Image Formats

Here is a list of common graphics and still-image formats:

  • BMP: Standard bit-mapped graphics format used on Windows computers.
  • FlashPix: A format for storing digital images, especially digital photographs, developed by Eastman Kodak Company.
  • GIF: Graphic Interchange Format. A common bit-mapped graphics file format used on the web.
  • JPEG/JFIF: Joint Photographics Experts Group. A “lossy” compression file format used for images. JFIF is JPEG File Interchange Format.
  • MacPaint (PNTG): A monochrome file format used on early versions of the Mac operating system.
  • Photo JPEG: An extremely popular file format because it can create highly compressed yet good-looking graphics files. You can choose grayscale or color as well as the amount of compression.
  • Photoshop (PSD): You can import files created or saved in the Photoshop format, along with multilayered Photoshop files. (For more information, see Compositing and Layering.)
  • PICS: A file format used on Mac OS computers for animation sequences. The format is no longer used, in favor of QuickTime.
  • PICT: A common image format used on Mac OS computers. PICT files can use any of the standard QuickTime codecs for compression in color or grayscale.
  • PNG: Portable Network Graphics. A file format for bitmapped graphic images designed as the successor to GIF.
  • QuickTime Image File (QTIF): A QuickTime container file that contains an image using a supported QuickTime codec.
  • SGI: Silicon Graphics Image file format.
  • TARGA (TGA): The Targa file format. An uncompressed file format that stores images with millions of colors. Targa files are supported by nearly every platform and media application.
  • TIFF: Common on Mac OS and Windows computers. TIFF files allow color depths from dithered black and white to millions of colors and one form of compression.

Note: Almost all of these file formats can contain an alpha channel.

Audio File Formats

The following is a list of common audio file formats:

  • AAC or .mp4: Advanced audio coding. This format is a continuation of the MP3 audio format, improving quality while reducing file size. This audio format is commonly used in MPEG-4 multimedia files, and can support features such as surround sound.
  • AIFF/AIFC: Audio Interchange File Format. An audio format for Mac computers commonly used for storing uncompressed, CD-quality sound (similar to WAVE files for Windows-based PCs).
  • Audio CD Data (.cdda): Compact Disc Digital Audio. Audio files stored on CD.
  • MP3: Short for MPEG-1, layer 3 audio. This is a very popular format for online music distribution.
  • Sound Designer II: Sound Designer II, sometimes seen abbreviated as SD2. A monophonic and stereophonic audio file format, originally developed by Digidesign for Mac computers.
  • System 7 Sound: An older sound format developed by Apple.
  • uLaw: File format developed by Sun that provides logarithmic encoding for a larger dynamic range than normal 8-bit samples. Approximately equivalent to 12-bit samples, but suffers from more noise than linear encodings.
  • WAVE: The format for storing sound in files developed jointly by Microsoft and IBM.

For a complete list of all QuickTime-compatible file formats, see the documentation that came with QuickTime Pro or visit Apple’s QuickTime website at http://www.apple.com/quicktime.