VTMultiPassStorageCreate(allocator:fileURL:timeRange:options:multiPassStorageOut:)

Declaration

func VTMultiPassStorageCreate(allocator: CFAllocator?, fileURL: CFURL?, timeRange: CMTimeRange, options: CFDictionary?, multiPassStorageOut: UnsafeMutablePointer<VTMultiPassStorage?>) -> OSStatus

Parameters

• allocator:

  An allocator for the session. Pass NULL to use the default allocator.

• fileURL:

  Specifies where to put the backing file for the multipass storage object. If you pass NULL for fileURL, the video toolbox will pick a unique temporary file name.

• timeRange:

  Gives a hint to the multipass storage about valid time stamps for data. You can pass kCMTimeRangeInvalid if you do not want to provide a time range hint.

• options:

  If the file did not exist when the storage was created, the file will be deleted when the multipass storage object is finalized, unless you set the Kvtmultipassstoragecreationoption_donotdelete option to Kcfbooleantrue in the options dictionary.

• multiPassStorageOut:

  A pointer to the newly created multipass storage object.

Discussion

You can use the multipass storage object to perform multipass encoding; see kVTCompressionPropertyKey_MultiPassStorage.

Call CFRelease to release the multipass storage object when you are done with it.