QuickTime Plugin

Overview

On Macintosh systems, a plugin is available to save data as QuickTime movies.

Topics

Frame rate

Use the frame rate option to specify the number of frames per second for the generated movie.

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The compression schemes available will depend on which compression components are installed on your system. Listed below are compression components that Apple included with QuickTime 1.6 and have been included with subsequent versions of QuickTime. By default, the plugin will use the Photo (JPEG) compression scheme.

Animation: Compresses the movie with a lossless (run-length encoding) scheme appropriate for sequences of drawings.
Cinepak: Is like the Video scheme but decompresses more quickly at the expense of much longer compression times. The compression algorithm is affected by the quality and key frame interval parameters.
Photo (JPEG): Compresses each frame of the movie separately with the standard JPEG lossy compression algorithm. The quality parameter controls the lossiness of the compression.
Graphics: This is a lossless compression algorithm which, in comparison to the Animation compression scheme, is more effective at compression but takes longer to decompress.
Video: Compresses the movie with a lossy compression scheme designed for desktop video. The quality parameter affects lossiness of the compression.

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Compression Implementation

In some instances, more than one component implementing the same compression scheme may be installed on your system. Use the implementation parameter to set the heuristic the plugin uses to choose the component. The available options are:

Any: Use the first component which implements the compression scheme.
Best Speed: Use the fastest component which implements the compression scheme.
Best Fidelity: Use the most accurate component which implements the compression scheme.
Best Size: Use the component which will produce the smallest compressed output.

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Quality

The quality parameter controls how much the decompressed version of the compressed data differs from the original data. Allowing greater deviations can decrease the size of the compressed output. Some compression schemes do not allow control over the amount of deviation and ignore this parameter. The available options are:

Minimum: Allows the most deviations from the original.
Low: Allows the most deviations from the original while still maintaining "acceptable" display characteristics.
Normal: Allows an amount of deviations acceptable for normal image quality.
High: Allows the smallest amount of deviation possible while maintaining "reasonable" performance.
Maximum: Allows the fewest possible deviations.
Lossless: If the compression scheme supports lossless compression, then this option is available to allow no deviation from the original.

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Temporal Compression

Some compression schemes can do more than treat each image in a sequence independently. For those compression schemes, you can turn on the "Temporal Compression" toggle to allow the compression scheme to use the similarities and differences between images to improve compression. When temporal compression is enabled, the key frame interval also affects the compressed results.

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Key Frame Interval

A larger interval between key frames will give a higher level of compression and quicker playback than a smaller key frame interval. A smaller key frame interval is useful if you wish to stop and start the movie to examine individual frames. Key frame intervals in the range of 1 to 60 frames are allowed.

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Command Line

When Image Capture is run from the command line on Mac OS X, you can use

    -format=qt

as an option to Image Capture to have it generate a QuickTime movie. To further control the QuickTime output, you can append any of the following to the -format=qt option (when appending first insert a comma: i.e.

    -format=qt,frate=5,compress="Sorenson Video 3",temporal

frate=frames_per_second: Sets the suggested playback rate; frames_per_second can be any value between 0.25 and 99. When you do not set the playback rate, the playback rate for the generated movie will be 15 frames per second.
compress=algorithm_name: Sets the compression algorithm to use. The allowed names are the same as those listed in the Image Capture user interface and will vary depending on which compression components are installed on your system. Some of the names contain spaces or the other characters which may have special meaning to the shell so quote the name if necessary. The algorithms that Apple included with QuickTime 1.6 and have been included with subsequent versions of QuickTime are: Animation, Cinepak, Photo (JPEG), Graphics, and Video (consult the compression topic for more details about those algorithms). If you do not specify a compress algorithm, the Photo (JPEG) algorithm will be used.
select=criteria: Sets which compression component is used if you have more than one component installed which implements the compression algorithm you selected. The allowed values for criteria are any, best_speed, best_fidelity, and best_size; for more details about what those choices mean, consult the compression implementation topic. Unless you specify otherwise, the first implementation (i.e. the "any" option) of an algorithm will be the implementation that is used.
qual=quality: Sets the quality of the output when the QuickTime movie is decompressed. The allowed values for quality are min, low, normal, high, max, and lossless; for more information about what those choices mean, consult the quality topic. If you do not specify the quality, the movie will have "normal" quality when decompressed.
temporal: Include this option to enable temporal compression. For compression schemes that always treat each frame independently, this option has no effect.
kdist=key_frame_interval: Sets the key frame interval to use when temporal compression is enabled. key_frame_interval can be any integer value between 1 and 60. If you do not set the key frame interval, the generated movie will use a key frame interval of 5.

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Overview

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