Encapsulates sample waves used for playback. More...

#include <DLS.h>

Inheritance diagram for DLS::Sample:

Public Member Functions
void *	LoadSampleData ()
	Load sample data into RAM. More...

void	ReleaseSampleData ()
	Free sample data from RAM. More...

file_offset_t	GetSize () const
	Returns sample size. More...

void	Resize (file_offset_t NewSize)
	Resize sample. More...

file_offset_t	SetPos (file_offset_t SampleCount, RIFF::stream_whence_t Whence=RIFF::stream_start)
	Sets the position within the sample (in sample points, not in bytes). More...

file_offset_t	Read (void *pBuffer, file_offset_t SampleCount)
	Reads SampleCount number of sample points from the current position into the buffer pointed by pBuffer and increments the position within the sample. More...

file_offset_t	Write (void *pBuffer, file_offset_t SampleCount)
	Write sample wave data. More...

virtual void	UpdateChunks (progress_t *pProgress)
	Apply sample and its settings to the respective RIFF chunks. More...

virtual void	DeleteChunks ()
	Remove all RIFF chunks associated with this Sample object. More...

virtual void	CopyAssign (const Sample *orig)
	Make a deep copy of the Sample object given by orig and assign it to this object. More...

Resource *	GetParent ()

const Resource *	GetParent () const

void	GenerateDLSID ()
	Generates a new DLSID for the resource.

virtual void	CopyAssign (const Resource *orig)
	Make a deep copy of the Resource object given by orig and assign it to this object. More...

Static Public Member Functions
static void	GenerateDLSID (dlsid_t *pDLSID)

Public Attributes
uint16_t	FormatTag
	Format ID of the waveform data (should be DLS_WAVE_FORMAT_PCM for DLS1 compliant files, this is also the default value if Sample was created with Instrument::AddSample()).

uint16_t	Channels
	Number of channels represented in the waveform data, e.g. 1 for mono, 2 for stereo (defaults to 1=mono if Sample was created with Instrument::AddSample() previously).

uint32_t	SamplesPerSecond
	Sampling rate at which each channel should be played (defaults to 44100 if Sample was created with Instrument::AddSample() previously).

uint32_t	AverageBytesPerSecond
	The average number of bytes per second at which the waveform data should be transferred (Playback software can estimate the buffer size using this value).

uint16_t	BlockAlign
	The block alignment (in bytes) of the waveform data. Playback software needs to process a multiple of BlockAlign bytes of data at a time, so the value of BlockAlign can be used for buffer alignment.

uint16_t	BitDepth
	Size of each sample per channel (only if known sample data format is used, 0 otherwise).

file_offset_t	SamplesTotal
	Reflects total number of sample points (only if known sample data format is used, 0 otherwise), do not bother to change this value, it will not be saved.

uint	FrameSize
	Reflects the size (in bytes) of one single sample point (only if known sample data format is used, 0 otherwise). Caution: with the current version of libgig you have to upate this field by yourself whenever you change one of the following fields: Channels, BitDepth ! Ignoring this might lead to undesired behavior when i.e. calling Resize(), SetPos(), Write() or Read().

Info *	pInfo
	Points (in any case) to an Info object, providing additional, optional infos and comments.

dlsid_t *	pDLSID
	Points to a dlsid_t structure if the file provided a DLS ID else is NULL.

Protected Member Functions
	Sample (File pFile, RIFF::List waveList, file_offset_t WavePoolOffset)
	Constructor. More...

virtual	~Sample ()
	Destructor. More...

void	CopyAssignCore (const Sample *orig)
	Make a deep copy of the Sample object given by orig (without the actual sample waveform data however) and assign it to this object. More...

Protected Attributes
RIFF::List *	pWaveList

RIFF::Chunk *	pCkData

RIFF::Chunk *	pCkFormat

file_offset_t	ullWavePoolOffset

Resource *	pParent

RIFF::List *	pResourceList

Detailed Description

Encapsulates sample waves used for playback.

In case you created a new sample with File::AddSample(), you should first update all attributes with the desired meta informations (amount of channels, bit depth, sample rate, etc.), then call Resize() with the desired sample size. The latter will create the mandatory RIFF chunk which will hold the sample wave data.

Definition at line 456 of file DLS.h.

Constructor & Destructor Documentation

◆ Sample()

DLS::Sample::Sample	(	File *	pFile,
		RIFF::List *	waveList,
		file_offset_t	WavePoolOffset
	)

protected

Constructor.

Load an existing sample or create a new one. A 'wave' list chunk must be given to this constructor. In case the given 'wave' list chunk contains a 'fmt' and 'data' chunk, the format and sample data will be loaded from there, otherwise default values will be used and those chunks will be created when File::Save() will be called later on.

Parameters

pFile	- pointer to DLS::File where this sample is located (or will be located)
waveList	- pointer to 'wave' list chunk which is (or will be) associated with this sample
WavePoolOffset	- offset of this sample data from wave pool ('wvpl') list chunk

Definition at line 787 of file DLS.cpp.

References AverageBytesPerSecond, BitDepth, BlockAlign, Channels, FormatTag, FrameSize, RIFF::Chunk::GetFile(), RIFF::File::GetFileOffsetSize(), RIFF::Chunk::GetSize(), RIFF::List::GetSubChunk(), RIFF::Chunk::ReadUint16(), RIFF::Chunk::ReadUint32(), SamplesPerSecond, SamplesTotal, and RIFF::Chunk::SetPos().

◆ ~Sample()

DLS::Sample::~Sample ( )

protectedvirtual

Destructor.

Frees all memory occupied by this sample.

Reimplemented in gig::Sample.

Definition at line 827 of file DLS.cpp.

References RIFF::Chunk::ReleaseChunkData().

Member Function Documentation

◆ CopyAssign() [1/2]

void Resource::CopyAssign ( const Resource * orig )

virtualinherited

Make a deep copy of the Resource object given by orig and assign it to this object.

Parameters

orig	- original Resource object to be copied from

Definition at line 601 of file DLS.cpp.

References DLS::Info::CopyAssign(), and DLS::Resource::pInfo.

Referenced by DLS::Region::CopyAssign(), and CopyAssignCore().

◆ CopyAssign() [2/2]

void DLS::Sample::CopyAssign ( const Sample * orig )

virtual

Make a deep copy of the Sample object given by orig and assign it to this object.

Parameters

orig	- original Sample object to be copied from

Definition at line 881 of file DLS.cpp.

References CopyAssignCore(), FrameSize, RIFF::Chunk::GetPos(), GetSize(), LoadSampleData(), Read(), Resize(), SetPos(), and RIFF::Chunk::SetPos().

◆ CopyAssignCore()

void DLS::Sample::CopyAssignCore ( const Sample * orig )

protected

Make a deep copy of the Sample object given by orig (without the actual sample waveform data however) and assign it to this object.

This is a special internal variant of CopyAssign() which only copies the most mandatory member variables. It will be called by gig::Sample descendent instead of CopyAssign() since gig::Sample has its own implementation to access and copy the actual sample waveform data.

Parameters

orig	- original Sample object to be copied from

Definition at line 861 of file DLS.cpp.

References AverageBytesPerSecond, BitDepth, BlockAlign, Channels, DLS::Resource::CopyAssign(), FormatTag, FrameSize, SamplesPerSecond, and SamplesTotal.

Referenced by CopyAssign(), and gig::Sample::CopyAssignMeta().

◆ DeleteChunks()

void DLS::Sample::DeleteChunks ( )

virtual

Remove all RIFF chunks associated with this Sample object.

See Storage::DeleteChunks() for details.

Reimplemented from DLS::Resource.

Definition at line 838 of file DLS.cpp.

References DLS::Resource::DeleteChunks(), RIFF::List::DeleteSubChunk(), and RIFF::Chunk::GetParent().

Referenced by DLS::File::DeleteSample(), and gig::File::DeleteSample().

◆ GetSize()

file_offset_t DLS::Sample::GetSize ( ) const

Returns sample size.

Returns the sample wave form's data size (in sample points). This is actually the current, physical size (converted to sample points) of the RIFF chunk which encapsulates the sample's wave data. The returned value is dependant to the current FrameSize value.

Returns: number of sample points or 0 if FormatTag != DLS_WAVE_FORMAT_PCM

See also: FrameSize, FormatTag

Definition at line 950 of file DLS.cpp.

References FormatTag, FrameSize, and RIFF::Chunk::GetSize().

Referenced by CopyAssign(), gig::Sample::CopyAssignMeta(), Write(), and gig::Sample::Write().

◆ LoadSampleData()

void * DLS::Sample::LoadSampleData ( )

Load sample data into RAM.

In case the respective 'data' chunk exists, the sample data will be loaded into RAM (if not done already) and a pointer to the data in RAM will be returned. If this is a new sample, you have to call Resize() with the desired sample size to create the mandatory RIFF chunk for the sample wave data.

You can call LoadChunkData() again if you previously scheduled to enlarge the sample data RIFF chunk with a Resize() call. In that case the buffer will be enlarged to the new, scheduled size and you can already place the sample wave data to the buffer and finally call File::Save() to enlarge the sample data's chunk physically and write the new sample wave data in one rush. This approach is definitely recommended if you have to enlarge and write new sample data to a lot of samples.

Caution: the buffer pointer will be invalidated once File::Save() was called. You have to call LoadChunkData() again to get a new, valid pointer whenever File::Save() was called.

Returns: pointer to sample data in RAM, NULL in case respective 'data' chunk does not exist (yet)

Exceptions

Exception if data buffer could not be enlarged

See also: Resize(), File::Save()

Definition at line 927 of file DLS.cpp.

References RIFF::Chunk::LoadChunkData().

Referenced by CopyAssign().

◆ Read()

file_offset_t DLS::Sample::Read	(	void *	pBuffer,
		file_offset_t	SampleCount
	)

Reads SampleCount number of sample points from the current position into the buffer pointed by pBuffer and increments the position within the sample.

Use this method and SetPos() if you don't want to load the sample into RAM, thus for disk streaming.

Parameters

pBuffer	destination buffer
SampleCount	number of sample points to read

Definition at line 1028 of file DLS.cpp.

References FormatTag, FrameSize, and RIFF::Chunk::Read().

Referenced by CopyAssign().

◆ ReleaseSampleData()

void DLS::Sample::ReleaseSampleData ( )

Free sample data from RAM.

In case sample data was previously successfully loaded into RAM with LoadSampleData(), this method will free the sample data from RAM.

Definition at line 936 of file DLS.cpp.

References RIFF::Chunk::ReleaseChunkData().

◆ Resize()

void DLS::Sample::Resize ( file_offset_t NewSize )

Resize sample.

Resizes the sample's wave form data, that is the actual size of sample wave data possible to be written for this sample. This call will return immediately and just schedule the resize operation. You should call File::Save() to actually perform the resize operation(s) "physically" to the file. As this can take a while on large files, it is recommended to call Resize() first on all samples which have to be resized and finally to call File::Save() to perform all those resize operations in one rush.

The actual size (in bytes) is dependant to the current FrameSize value. You may want to set FrameSize before calling Resize().

Caution: You cannot directly write to enlarged samples before calling File::Save() as this might exceed the current sample's boundary!

Also note: only DLS_WAVE_FORMAT_PCM is currently supported, that is FormatTag must be DLS_WAVE_FORMAT_PCM. Trying to resize samples with other formats will fail!

Parameters

NewSize - new sample wave data size in sample points (must be greater than zero)

Exceptions

Exception	if FormatTag != DLS_WAVE_FORMAT_PCM
Exception	if NewSize is less than 1 or unrealistic large

See also: File::Save(), FrameSize, FormatTag

Definition at line 983 of file DLS.cpp.

References RIFF::List::AddSubChunk(), FormatTag, FrameSize, RIFF::List::GetSubChunk(), and RIFF::Chunk::Resize().

Referenced by CopyAssign(), and gig::Sample::Resize().

◆ SetPos()

file_offset_t DLS::Sample::SetPos	(	file_offset_t	SampleCount,
		RIFF::stream_whence_t	Whence = `RIFF::stream_start`
	)

Sets the position within the sample (in sample points, not in bytes).

Use this method and Read() if you don't want to load the sample into RAM, thus for disk streaming.

Also note: only DLS_WAVE_FORMAT_PCM is currently supported, that is FormatTag must be DLS_WAVE_FORMAT_PCM. Trying to reposition the sample with other formats will fail!

Parameters

SampleCount	number of sample points
Whence	to which relation SampleCount refers to

Returns: new position within the sample, 0 if FormatTag != DLS_WAVE_FORMAT_PCM

Exceptions

Exception if no data RIFF chunk was created for the sample yet

See also: FrameSize, FormatTag

Definition at line 1010 of file DLS.cpp.

References FormatTag, FrameSize, and RIFF::Chunk::SetPos().

Referenced by CopyAssign().

◆ UpdateChunks()

void DLS::Sample::UpdateChunks ( progress_t * pProgress )

virtual

Apply sample and its settings to the respective RIFF chunks.

You have to call File::Save() to make changes persistent.

Parameters

pProgress - callback function for progress notification

Exceptions

Exception if FormatTag != DLS_WAVE_FORMAT_PCM or no sample data was provided yet

Reimplemented from DLS::Resource.

Reimplemented in gig::Sample.

Definition at line 1062 of file DLS.cpp.

References RIFF::List::AddSubChunk(), AverageBytesPerSecond, BitDepth, BlockAlign, Channels, FormatTag, RIFF::List::GetSubChunk(), RIFF::Chunk::LoadChunkData(), SamplesPerSecond, and DLS::Resource::UpdateChunks().

Referenced by gig::Sample::UpdateChunks().

◆ Write()

file_offset_t DLS::Sample::Write	(	void *	pBuffer,
		file_offset_t	SampleCount
	)

Write sample wave data.

Writes SampleCount number of sample points from the buffer pointed by pBuffer and increments the position within the sample. Use this method to directly write the sample data to disk, i.e. if you don't want or cannot load the whole sample data into RAM.

You have to Resize() the sample to the desired size and call File::Save() before using Write().

Parameters

pBuffer	- source buffer
SampleCount	- number of sample points to write

Exceptions

Exception if current sample size is too small

See also: LoadSampleData()

Definition at line 1048 of file DLS.cpp.

References FormatTag, FrameSize, GetSize(), and RIFF::Chunk::Write().

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

Public Member Functions

Static Public Member Functions

Public Attributes

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ Sample()

◆ ~Sample()

Member Function Documentation

◆ CopyAssign() [1/2]

◆ CopyAssign() [2/2]

◆ CopyAssignCore()

◆ DeleteChunks()

◆ GetSize()

◆ LoadSampleData()

◆ Read()

◆ ReleaseSampleData()

◆ Resize()

◆ SetPos()

◆ UpdateChunks()

◆ Write()