om::sound::io::HRTFTranscoder Class Reference

A class that encodes and decodes the HRTF format. More...

#include <omSoundHRTFTranscoder.h>

Inheritance diagram for om::sound::io::HRTFTranscoder:

Public Member Functions
virtual const ResourceFormat &	getResourceFormat () const
	Return an object that represents the resource format that this transcoder can read and write. More...
virtual Bool	canEncode (const HRTF &hrtf) const
	Return whether or not this transcoder is able to encode the specified resource. More...
virtual Bool	encode (const ResourceID &identifier, const HRTF &hrtf, const ResourceSet *resourceSet=((void *) 0), ResourceManager *manager=((void *) 0))
	Save the specified HRTF at the specified ID location. More...
virtual Bool	canDecode (const ResourceID &identifier) const
	Return whether or not the specified identifier refers to a valid resource for this transcoder. More...
virtual HRTF *	decode (ResourceID &identifier, ResourceSet *resourceSet=((void *) 0), ResourceManager *manager=((void *) 0))
	Load the HRTF pointed to by the specified identifier. More...
Public Member Functions inherited from om::resources::ResourceTypeTranscoder< DataType >
virtual const ResourceType &	getResourceType () const
	Return an object that represents the resource type that this transcoder can read and write. More...
virtual Bool	canEncode (const DataType &resource) const =0
	Return whether or not this transcoder is able to encode the specified resource. More...
virtual Bool	encode (const ResourceID &identifier, const DataType &resource, const ResourceSet *resourceSet=((void *) 0), ResourceManager *manager=((void *) 0))=0
	Save the specified resource object at the specified ID location. More...
Public Member Functions inherited from om::resources::ResourceTranscoder
virtual	~ResourceTranscoder ()
	Destroy a resource transcoder and release all of its resources. More...

Static Public Attributes
static const ResourceFormat	FORMAT
	The resource format for HRTFs. More...

Detailed Description

A class that encodes and decodes the HRTF format.

Version 1 of the HRTF binary format.

Primitive types:

• float64 - double-precision IEEE 754 floating point number.
• float32 - single-precision IEEE 754 floating point number.
• uint8 - 8-bit unsigned integer.
• uint64 - 64-bit unsigned integer.
• string - UTF-8 encoded string, given by a uint64 length followed by that number of UTF8 uint8 code points, padded to the nearest 4-byte boundary.

The version-independent 16-byte header for the file is as follows:

• Bytes 0 through 8: The ASCII character string 'SOUNDHRTF'.
• Byte 9: uint8 indicating the version number of the HRTF format.
• Byte 10: uint8 that specifies the endianness of the file, 0 if little endian, 1 if big endian.
• Byte 11: reserved/padding.
• Bytes 12 through 15: uint32 indicating a checksum of the rest of the file after the header. The checksum is computed by summing the value of every byte in the file as interpreted as 8-bit integers and allowing overflow. This value is provided to detect corruption of the file. A value of 0 indicates that the checksum is not used.

The version-specific HRTF header contains basic information about the HRTF:

• sizeInBytes: uint64 specifying the total encoded size in bytes of the header.
• numChannels: uint64 specifying the number of channels in the HRTF.
• sampleRate: float64 specifying the sample rate of the HRTF in hertz.
• orientation: 9*float32 specifying a 3x3 orthonormal rotation matrix that is applied to the HRTF.
• name: string specifying the name of the person the HRTF was measured for.
• description: string containing a description of the HRTF and/or how it was measured.
• organization: string containing the name of the organization that created the HRTF.
• license: string containing the license of the HRTF.

The channels for the HRTF: (per channel)

• sizeInBytes: uint64 specifying the total encoded size in bytes of this channel.
• numSamples: uint64 specifying the number of impulse response samples in this channel.
• position: 3*float32 cartesian coordinate of the channel relative to the listener, in meters.
• name: string specifying the name of the channel.
• samples: numSamples samples for the channel.

Each IR sample for a channel:

• sizeInBytes: uint64 specifying the total encoded size in bytes of this sample.
• direction: 3*float32 unit-length cartesian direction of the IR sample relative to the channel's position.
• sampleDelay: uint64 indicating the broadband delay in samples for this IR measurement.
• irLength: uint64 indicating the length of the IR in samples.
• ir: irLength*float32 samples for the IR.

Member Function Documentation

virtual const ResourceFormat& om::sound::io::HRTFTranscoder::getResourceFormat ( ) const

virtual

Return an object that represents the resource format that this transcoder can read and write.

Implements om::resources::ResourceTranscoder.

virtual Bool om::sound::io::HRTFTranscoder::canEncode ( const HRTF &  hrtf ) const

virtual

Return whether or not this transcoder is able to encode the specified resource.

virtual Bool om::sound::io::HRTFTranscoder::encode ( const ResourceID &  identifier, const HRTF &  hrtf, const ResourceSet *  resourceSet = ((void *) 0), ResourceManager *  manager = ((void *) 0)  )

virtual

Save the specified HRTF at the specified ID location.

The method returns whether or not the resource was successfully written.

virtual Bool om::sound::io::HRTFTranscoder::canDecode ( const ResourceID &  identifier ) const

virtual

Return whether or not the specified identifier refers to a valid resource for this transcoder.

If the identifier represents a valid resource, TRUE is returned. Otherwise, if the resource is not valid, FALSE is returned.

Implements om::resources::ResourceTranscoder.

virtual HRTF* om::sound::io::HRTFTranscoder::decode ( ResourceID &  identifier, ResourceSet *  resourceSet = ((void *) 0), ResourceManager *  manager = ((void *) 0)  )

virtual

Load the HRTF pointed to by the specified identifier.

The caller can supply a pointer to a resource manager which can be used to manage the creation of child resources.

If the method fails, the return value will be NULL.

Implements om::resources::ResourceTypeTranscoder< DataType >.

Member Data Documentation

const ResourceFormat om::sound::io::HRTFTranscoder::FORMAT

static

The resource format for HRTFs.

---

The documentation for this class was generated from the following file:

• omSoundHRTFTranscoder.h