# Decompression Properties Properties used to configure a VideoToolbox decompression session. ## Topics ### Asynchronous State [`kVTDecompressionPropertyKey_MaxOutputPresentationTimeStampOfFramesBeingDecoded`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_MaxOutputPresentationTimeStampOfFramesBeingDecoded) The maximum output presentation timestamp of the frames currently being decoded. [`kVTDecompressionPropertyKey_MinOutputPresentationTimeStampOfFramesBeingDecoded`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_MinOutputPresentationTimeStampOfFramesBeingDecoded) The minimum output presentation timestamp of the frames currently being decoded. [`kVTDecompressionPropertyKey_NumberOfFramesBeingDecoded`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_NumberOfFramesBeingDecoded) Returns the number of frames currently being decoded. ### Content [`kVTDecompressionPropertyKey_ContentHasInterframeDependencies`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_ContentHasInterframeDependencies) An optional Boolean property indicating if the content being decoded has interframe dependencies, if the decoder knows. ### Decoder Behavior [`kVTDecompressionProperty_TemporalLevelLimit`](/documentation/VideoToolbox/kVTDecompressionProperty_TemporalLevelLimit) [`kVTDecompressionPropertyKey_AllowBitstreamToChangeFrameDimensions`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_AllowBitstreamToChangeFrameDimensions) A Boolean value that indicates whether a decoder is allowed to output buffers matching reduced frame dimensions in the bitstream rather than under-filling them. [`kVTDecompressionPropertyKey_DeinterlaceMode`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_DeinterlaceMode) Modes for requesting a specific deinterlacing technique. [`kVTDecompressionPropertyKey_FieldMode`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_FieldMode) Modes for special handling of interlaced content (optional). [`kVTDecompressionPropertyKey_MaximizePowerEfficiency`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_MaximizePowerEfficiency) [`kVTDecompressionPropertyKey_OnlyTheseFrames`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_OnlyTheseFrames) Requests that frames be filtered by type. [`kVTDecompressionPropertyKey_PixelFormatsWithReducedResolutionSupport`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_PixelFormatsWithReducedResolutionSupport) Pixel formats that support reduced-resolution decoding (optional). [`kVTDecompressionPropertyKey_RealTime`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_RealTime) A Boolean value indicating whether it’s recommended that the video decoder perform decompression in real time. [`kVTDecompressionPropertyKey_ReducedCoefficientDecode`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_ReducedCoefficientDecode) Requests approximation during decoding. [`kVTDecompressionPropertyKey_ReducedFrameDelivery`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_ReducedFrameDelivery) The proportion of frames that should be delivered, indicating that the rest may be dropped. [`kVTDecompressionPropertyKey_ReducedResolutionDecode`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_ReducedResolutionDecode) Request decoding at smaller resolutions than full-size (optional). [`kVTDecompressionPropertyKey_SuggestedQualityOfServiceTiers`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_SuggestedQualityOfServiceTiers) An array of dictionaries that describe decreasing quality-of-service levels that clients can use to maintain realtime playback (optional). [`kVTDecompressionPropertyKey_SupportedPixelFormatsOrderedByPerformance`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_SupportedPixelFormatsOrderedByPerformance) An array indicating speed tradeoffs between pixel formats (optional). [`kVTDecompressionPropertyKey_SupportedPixelFormatsOrderedByQuality`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_SupportedPixelFormatsOrderedByQuality) An array indicating quality levels among pixel formats. [`kVTDecompressionPropertyKey_ThreadCount`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_ThreadCount) The number of threads used by a codec or the suggested number of threads to use (optional). ### Hardware Acceleration [`kVTDecompressionPropertyKey_UsingHardwareAcceleratedVideoDecoder`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_UsingHardwareAcceleratedVideoDecoder) Indicates if a hardware-accelerated video decoder is being used. [`kVTVideoDecoderSpecification_EnableHardwareAcceleratedVideoDecoder`](/documentation/VideoToolbox/kVTVideoDecoderSpecification_EnableHardwareAcceleratedVideoDecoder) A Boolean value indicating whether VideoToolbox uses a hardware-accelerated video decoder, if available. [`kVTVideoDecoderSpecification_RequireHardwareAcceleratedVideoDecoder`](/documentation/VideoToolbox/kVTVideoDecoderSpecification_RequireHardwareAcceleratedVideoDecoder) A Boolean value indicating whether to require hardware-accelerated decoding. ### Multi-Image Decompression [`kVTDecompressionPropertyKey_RequestedMVHEVCVideoLayerIDs`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_RequestedMVHEVCVideoLayerIDs) Requests multi-image decoding of specific MV-HEVC video layers. ### Per-Frame Decoder Options [`kVTDecodeFrameOptionKey_ContentAnalyzerCropRectangle`](/documentation/VideoToolbox/kVTDecodeFrameOptionKey_ContentAnalyzerCropRectangle) [`kVTDecodeFrameOptionKey_ContentAnalyzerRotation`](/documentation/VideoToolbox/kVTDecodeFrameOptionKey_ContentAnalyzerRotation) ### Pixel Buffer Pools [`kVTDecompressionPropertyKey_OutputPoolRequestedMinimumBufferCount`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_OutputPoolRequestedMinimumBufferCount) The requested minimum buffer count that a decompression session should use for its output pixel buffer pool, without releasing buffers while the number in use is below this level. [`kVTDecompressionPropertyKey_PixelBufferPool`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_PixelBufferPool) A pixel buffer pool for pixel buffers being output by the decompression session. [`kVTDecompressionPropertyKey_PixelBufferPoolIsShared`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_PixelBufferPoolIsShared) A Boolean value indicating whether a common pixel buffer pool is shared between the video decoder and the session client. ### Post-Decompression Processing [`kVTDecompressionPropertyKey_DecoderProducesRAWOutput`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_DecoderProducesRAWOutput) A value that indicates whether the decoder can produce RAW output requiring a RAW processing session for post-decode processing. [`kVTDecompressionPropertyKey_GeneratePerFrameHDRDisplayMetadata`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_GeneratePerFrameHDRDisplayMetadata) A key that indicates to generate per frame HDR Metadata and attach it to the resulting decoded pixel buffers. [`kVTDecompressionPropertyKey_PixelTransferProperties`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_PixelTransferProperties) Specific pixel transfer features to be used during decompression. [`kVTDecompressionPropertyKey_PropagatePerFrameHDRDisplayMetadata`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_PropagatePerFrameHDRDisplayMetadata) [`kVTDecompressionPropertyKey_RequestRAWOutput`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_RequestRAWOutput) For decoders that produce RAW output, this property requests that the decompression session provides unprocessed output. [`kVTDecompressionPropertyKey_UsingGPURegistryID`](/documentation/VideoToolbox/kVTDecompressionPropertyKey_UsingGPURegistryID) [`kVTVideoDecoderSpecification_PreferredDecoderGPURegistryID`](/documentation/VideoToolbox/kVTVideoDecoderSpecification_PreferredDecoderGPURegistryID) [`kVTVideoDecoderSpecification_RequiredDecoderGPURegistryID`](/documentation/VideoToolbox/kVTVideoDecoderSpecification_RequiredDecoderGPURegistryID) --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)