After Effects scripting referenceAVItem object
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AVItem duration attribute
app.project.item(index).durationDescription
Returns the duration, in seconds, of the item. Still footage items have a duration of 0.
?In a CompItem, the value is linked to the duration of the composition, and is read/write. ?In a FootageItem, the value is linked to the duration of the mainSource object, and is read-only.
Type
Floating-point value in the range [0.0..10800.0]; read/write for a CompItem; otherwise, read-only.
AVItem footageMissing attribute
app.project.item(index).footageMissingDescription
When true, the AVItem is a placeholder, or represents footage with a source file that cannot be found. In this case, the path of the missing source file is in the missingFootagePath attribute of the footage item’s source-file object. See “FootageItem mainSource attribute” on page66 and “FileSource missingFootagePath attribute” on page61.
Type
Boolean; read-only.
AVItem frameDuration attribute
app.project.item(index).frameDurationDescription
Returns the length of a frame for this AVItem, in seconds. This is the reciprocal of frameRate. When set, the reciprocal is automatically set as a new frameRate value.
This attribute returns the reciprocal of the frameRate, which may not be identical to a value you set, if that value is not evenly divisible into 1.0 (for example, 0.3). Due to numerical limitations, (1 / (1 / 0.3)) is close to, but not exactly, 0.3.
If the AVItem is a FootageItem, this value is linked to the mainSource, and is read-only. To change it, set the conformFrameRate of the mainSource object. This sets both the frameRate and frameDuration of the FootageItem.
Type
Floating-point value in the range [1/99.. 1.0]; read-only for a FootageItem, otherwise read/write.
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After Effects scripting referenceAVItem object
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AVItem frameRate attribute
app.project.item(index).frameRateDescription
The frame rate of the AVItem, in frames-per-second. This is the reciprocal of the frameDuration. When set, the reciprocal is automatically set as a new frameDuration value.
?In a CompItem, the value is linked to the frameRate of the composition, and is read/write.
?In a FootageItem, the value is linked to the frameRate of the mainSource object, and is read-only. To change
it, set the conformFrameRate of the mainSource object. This sets both the frameRate and frameDuration of the FootageItem.
Type
Floating-point value in the range [1.0..99.0]; read-only for a FootageItem, otherwise read/write.
AVItem hasAudio attribute
app.project.item(index).hasAudioDescription
When true, the AVItem has an audio component.
?In a CompItem, the value is linked to the composition. ?In a FootageItem, the value is linked to the mainSource object.
Type
Boolean; read-only.
AVItem hasVideo attribute
app.project.item(index).hasVideoDescription
When true, the AVItem has an video component.
?In a CompItem, the value is linked to the composition. ?In a FootageItem, the value is linked to the mainSource object.
Type
Boolean; read-only.
AVItem height attribute
app.project.item(index).heightDescription
The height of the item in pixels.
?In a CompItem, the value is linked to the composition, and is read/write.
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After Effects scripting referenceAVItem object
33
?In a FootageItem, the value is linked to the mainSource object, and is read/write only if the mainSource
object is a SolidSource. Otherwise, it is read-only.
Type
Integer in the range [1...30000]; read/write, except as noted.
AVItem name attribute
app.project.item(index).name Description
The name of the item, as shown in the Project panel.
?In a FootageItem, the value is linked to the mainSource object. If the mainSource object is a FileSource, this
value controls the display name in the Project panel, but does not affect the file name.
Type
String; read/write.
AVItem pixelAspect attribute
app.project.item(index).pixelAspect Description
The pixel aspect ratio (PAR) of the item.
?In a CompItem, the value is linked to the composition. ?In a FootageItem, the value is linked to the mainSource object.
The value you retrieve after setting may be slightly different from the value you supplied. The following table compares the value as it appears in the UI with the more-accurate value returned by this attribute.
PAR in the After Effects UI0.9111.51.091.211.331.462
PAR returned by the pixelAspect attribute0.9090909090909111.5
1.094017094017091.212121212121211.333333333333331.458689458689462
Type
Floating-point value, in the range [0.01..100.0]; read/write.
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After Effects scripting referenceAVItem object
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AVItem proxySource attribute
app.project.item(index).proxySource Description
The FootageSource being used as a proxy. The attribute is read-only; to change it, call any of the AVItem methods that change the proxy source: setProxy(), setProxyWithSequence(), setProxyWithSolid(), or setProxyWithPlaceholder().
Type
FootageSource object; read-only.
AVItem setProxy() method
app.project.item(index).setProxy(file)Description
Sets a file as the proxy of this AVItem. Loads the specified file into a new FileSource object, sets this as the value of the proxySource attribute, and sets useProxy to true. It does not preserve the interpretation param-eters, instead using the user preferences. If the file has an unlabeled alpha channel, and the user preference says to ask the user what to do, the method estimates the alpha interpretation, rather than asking the user. This differs from setting a FootageItem's main source, but both actions are performed as in the user interface.
ParametersfileReturns
An ExtendScript File object for the file to be used as a proxy.
None.
AVItem setProxyToNone() method
app.project.item(index).setProxyToNone()Description
Removes the proxy from this AVItem, sets the value of proxySource to null, and sets the value of useProxy to false.
Parameters
None.
Returns
Nothing.
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After Effects scripting referenceAVItem object
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AVItem setProxyWithPlaceholder() method
app.project.item(index).setProxyWithPlaceholder(name, width, height, frameRate, duration)Description
Creates a PlaceholderSource object with specified values, sets this as the value of the proxySource attribute, and sets useProxy to true. It does not preserve the interpretation parameters, instead using the user prefer-ences.
NOTE: There is no direct way to set a placeholder as a proxy in the user interface; this behavior occurs when a proxy has been set and then moved or deleted.
Parametersnamewidth, heightframeRatedurationReturns
A string containing the name of the new object.
The pixel dimensions of the placeholder, an integer in the range [4..30000].The frames-per-second, an integer in the range [1..99].
The total length in seconds, up to 3 hours. An integer in the range [0.0..10800.0].
Nothing.
AVItem setProxyWithSequence() method
app.project.item(index).setProxyWithSequence(file, forceAlphabetical)Description
Sets a sequence of files as the proxy of this AVItem, with the option of forcing alphabetical order. Loads the specified file sequence into a new FileSource object, sets this as the value of the proxySource attribute, and sets useProxy to true. It does not preserve the interpretation parameters, instead using the user preferences. If any file has an unlabeled alpha channel, and the user preference says to ask the user what to do, the method estimates the alpha interpretation, rather than asking the user.
Parametersfile
forceAlphabeticalReturns
An ExtendScript File object for the first file in the sequence.When true, use the “Force alphabetical order” option.
Nothing.
AVItem setProxyWithSolid() method
app.project.item(index).setProxyWithSolid(color, name, width, height, pixelAspect)Description
Creates a SolidSource object with specified values, sets this as the value of the proxySource attribute, and sets useProxy to true. It does not preserve the interpretation parameters, instead using the user preferences.
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