cugl::audio::OGGDecoder Class Reference

#include <CUOGGDecoder.h>

Inheritance diagram for cugl::audio::OGGDecoder:

Public Member Functions
	OGGDecoder ()
	~OGGDecoder ()
bool	init (const char *file) override
bool	init (const std::string &file) override
void	dispose () override
Sint32	pagein (float *buffer) override
void	setPage (Uint64 page) override
Public Member Functions inherited from cugl::audio::AudioDecoder
	AudioDecoder ()
	~AudioDecoder ()
double	getDuration () const
Uint32	getSampleRate () const
Uint64	getLength () const
Uint32	getChannels () const
std::string	getFile () const
Uint32	getPageSize () const
bool	ready ()
Uint64	getPage () const
Uint64	getPageCount () const
void	rewind ()
Sint32	decode (float *buffer)

Static Public Member Functions
static std::shared_ptr< AudioDecoder >	alloc (const char *file)
static std::shared_ptr< AudioDecoder >	alloc (const std::string &file)

Protected Attributes
SDL_RWops *	_source
OggVorbis_File	_oggfile
int	_bitstream
Protected Attributes inherited from cugl::audio::AudioDecoder
Uint8	_channels
Uint32	_rate
Uint64	_frames
std::string	_file
Uint32	_pagesize
Uint64	_currpage
Uint64	_lastpage

Detailed Description

This class represents an OGG decoder.

This class only supports Vorbis encodings. It does not support Flac data encoded in an Ogg file container. It also does not support the newer Opus codec.

Ogg Vorbis supports up to 8 channels (7.1 stereo), though SDL is limited to 6 channels (5.1 stereo). The channel layout for Ogg data is nonstandard (e.g. channels > 3 are not stereo compatible), so this decoder standardizes the channel layout to agree with FLAC and other data encodings. The channels are interleaved.

OGG files are not guaranteed to have uniform page sizes. This decoder tries to balance memory requirements with efficiency in paging frame data.

A decoder is NOT thread safe. If a decoder is used by an audio thread, then it should not be accessed directly in the main thread, and vice versa.

Constructor & Destructor Documentation

OGGDecoder()

cugl::audio::OGGDecoder::OGGDecoder

(

)

Creates an initialized audio decoder

NEVER USE A CONSTRUCTOR WITH NEW. If you want to allocate an asset on the heap, use one of the static constructors instead.

~OGGDecoder()

cugl::audio::OGGDecoder::~OGGDecoder

(

)

Deletes this decoder, disposing of all resources.

Member Function Documentation

alloc() [1/2]

static std::shared_ptr<AudioDecoder> cugl::audio::OGGDecoder::alloc ( const char *  file )

inlinestatic

Creates a newly allocated decoder for the given OGG file.

This method will fail and return nullptr if the file does not contain Vorbis data.

Parameters

file	the source file for the decoder

Returns

a newly allocated decoder for the given OGG file.

alloc() [2/2]

static std::shared_ptr<AudioDecoder> cugl::audio::OGGDecoder::alloc ( const std::string &  file )

static

Creates a newly allocated decoder for the given OGG file.

This method will fail and return nullptr if the file does not contain Vorbis data.

Parameters

file	the source file for the decoder

Returns

a newly allocated decoder for the given OGG file.

dispose()

void cugl::audio::OGGDecoder::dispose ( )

overridevirtual

Deletes the decoder resources and resets all attributes.

This will close the associated file. You must reinitialize the decoder to use it.

Implements cugl::audio::AudioDecoder.

init() [1/2]

bool cugl::audio::OGGDecoder::init ( const char *  file )

inlineoverridevirtual

Initializes a new decoder for the given OGG file.

This method will fail if the file does not contain Vorbis data.

Parameters

file	the source file for the decoder

Returns

true if the decoder was initialized successfully

Reimplemented from cugl::audio::AudioDecoder.

init() [2/2]

bool cugl::audio::OGGDecoder::init ( const std::string &  file )

overridevirtual

Initializes a new decoder for the given OGG file.

This method will fail if the file does not contain Vorbis data.

Parameters

file	the source file for the decoder

Returns

true if the decoder was initialized successfully

Implements cugl::audio::AudioDecoder.

pagein()

Sint32 cugl::audio::OGGDecoder::pagein ( float *  buffer )

overridevirtual

Reads a page of data into the provided buffer.

The buffer should be able to hold channels * page size many elements. The data is interpretted as floats and channels are all interleaved. If a full page is read, this method should return the page size. If it reads less, it will return the number of frames read. It will return -1 on a processing error.

Parameters

buffer

The buffer to store the audio data

Returns

the number of frames actually read (-1 on error).

Implements cugl::audio::AudioDecoder.

setPage()

void cugl::audio::OGGDecoder::setPage ( Uint64  page )

overridevirtual

Sets the current page of this decoder

This value is the next page to be read in with the pagein() command. If the page is greater than the total number of pages, it will be set just beyond the last page.

Parameters

page	The new page of this decoder

Implements cugl::audio::AudioDecoder.

Member Data Documentation

_bitstream

int cugl::audio::OGGDecoder::_bitstream

protected

Reference to the logical bitstream for decoding

_oggfile

OggVorbis_File cugl::audio::OGGDecoder::_oggfile

protected

The OGG decoder struct

_source

SDL_RWops* cugl::audio::OGGDecoder::_source

protected

The file for loading in information

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

• include/cugl/audio/codecs/CUOGGDecoder.h