Encapsulates sample waves of Gigasampler/GigaStudio files used for playback. More...

#include <gig.h>

Inheritance diagram for gig::Sample:

Public Member Functions
buffer_t	LoadSampleData ()
	Loads (and uncompresses if needed) the whole sample wave into RAM. More...

buffer_t	LoadSampleData (file_offset_t SampleCount)
	Reads (uncompresses if needed) and caches the first SampleCount numbers of SamplePoints in RAM. More...

buffer_t	LoadSampleDataWithNullSamplesExtension (uint NullSamplesCount)
	Loads (and uncompresses if needed) the whole sample wave into RAM. More...

buffer_t	LoadSampleDataWithNullSamplesExtension (file_offset_t SampleCount, uint NullSamplesCount)
	Reads (uncompresses if needed) and caches the first SampleCount numbers of SamplePoints in RAM. More...

buffer_t	GetCache ()
	Returns current cached sample points. More...

void	ReleaseSampleData ()
	Frees the cached sample from RAM if loaded with LoadSampleData() previously. 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	GetPos () const
	Returns the current position in the sample (in sample points).

file_offset_t	Read (void pBuffer, file_offset_t SampleCount, buffer_t pExternalDecompressionBuffer=NULL)
	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	ReadAndLoop (void pBuffer, file_offset_t SampleCount, playback_state_t pPlaybackState, DimensionRegion pDimRgn, buffer_t pExternalDecompressionBuffer=NULL)
	Reads SampleCount number of sample points from the position stored in pPlaybackState into the buffer pointed by pBuffer and moves the position within the sample respectively, this method honors the looping informations of the sample (if any). More...

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

Group *	GetGroup () const
	Returns pointer to the Group this Sample belongs to. More...

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

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

void	CopyAssignWave (const Sample *orig)
	Should be called after CopyAssignMeta() and File::Save() sequence. More...

uint32_t	GetWaveDataCRC32Checksum ()
	Returns the CRC-32 checksum of the sample's raw wave form data at the time when this sample's wave form data was modified for the last time by calling Write(). More...

bool	VerifyWaveData (uint32_t *pActually=NULL)
	Checks the integrity of this sample's raw audio wave data. More...

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

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...

virtual void	CopyAssign (const Resource *orig)
	Make a deep copy of the Resource 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.

Static Public Member Functions
static buffer_t	CreateDecompressionBuffer (file_offset_t MaxReadSize)
	Allocates a decompression buffer for streaming (compressed) samples with Sample::Read(). More...

static void	DestroyDecompressionBuffer (buffer_t &DecompressionBuffer)
	Free decompression buffer, previously created with CreateDecompressionBuffer(). More...

static void	GenerateDLSID (dlsid_t *pDLSID)

Public Attributes
uint32_t	Manufacturer
	Specifies the MIDI Manufacturer's Association (MMA) Manufacturer code for the sampler intended to receive this file's waveform. If no particular manufacturer is to be specified, a value of 0 should be used.

uint32_t	Product
	Specifies the MIDI model ID defined by the manufacturer corresponding to the Manufacturer field. If no particular manufacturer's product is to be specified, a value of 0 should be used.

uint32_t	SamplePeriod
	Specifies the duration of time that passes during the playback of one sample in nanoseconds (normally equal to 1 / Samples Per Second, where Samples Per Second is the value found in the format chunk), don't bother to update this attribute, it won't be saved.

uint32_t	MIDIUnityNote
	Specifies the musical note at which the sample will be played at it's original sample rate.

uint32_t	FineTune
	Specifies the fraction of a semitone up from the specified MIDI unity note field. A value of 0x80000000 means 1/2 semitone (50 cents) and a value of 0x00000000 means no fine tuning between semitones.

smpte_format_t	SMPTEFormat
	Specifies the Society of Motion Pictures and Television E time format used in the following SMPTEOffset field. If a value of 0 is set, SMPTEOffset should also be set to 0.

uint32_t	SMPTEOffset
	The SMPTE Offset value specifies the time offset to be used for the synchronization / calibration to the first sample in the waveform. This value uses a format of 0xhhmmssff where hh is a signed value that specifies the number of hours (-23 to 23), mm is an unsigned value that specifies the number of minutes (0 to 59), ss is an unsigned value that specifies the number of seconds (0 to 59) and ff is an unsigned value that specifies the number of frames (0 to -1).

uint32_t	Loops
	Caution: Use the respective field in the DimensionRegion instead of this one! (Intended purpose: Number of defined sample loops. So far only seen single loops in gig files - please report if you encounter more!)

uint32_t	LoopID
	Specifies the unique ID that corresponds to one of the defined cue points in the cue point list (only if Loops > 0), as the Gigasampler format only allows one loop definition at the moment, this attribute isn't really useful for anything.

loop_type_t	LoopType
	Caution: Use the respective field in the DimensionRegion instead of this one! (Intended purpose: The type field defines how the waveform samples will be looped.)

uint32_t	LoopStart
	Caution: Use the respective field in the DimensionRegion instead of this one! (Intended purpose: The start value specifies the offset [in sample points] in the waveform data of the first sample to be played in the loop [only if Loops > 0].)

uint32_t	LoopEnd
	Caution: Use the respective field in the DimensionRegion instead of this one! (Intended purpose: The end value specifies the offset [in sample points] in the waveform data which represents the end of the loop [only if Loops > 0].)

uint32_t	LoopSize
	Caution: Use the respective fields in the DimensionRegion instead of this one! (Intended purpose: Length of the looping area [in sample points] which is equivalent to More...

uint32_t	LoopFraction
	The fractional value specifies a fraction of a sample at which to loop. This allows a loop to be fine tuned at a resolution greater than one sample. A value of 0 means no fraction, a value of 0x80000000 means 1/2 of a sample length. 0xFFFFFFFF is the smallest fraction of a sample that can be represented.

uint32_t	LoopPlayCount
	Number of times the loop should be played (a value of 0 = infinite).

bool	Compressed
	If the sample wave is compressed (probably just interesting for instrument and sample editors, as this library already handles the decompression in it's sample access methods anyway).

uint32_t	TruncatedBits
	For 24-bit compressed samples only: number of bits truncated during compression (0, 4 or 6)

bool	Dithered
	For 24-bit compressed samples only: if dithering was used during compression with bit reduction.

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, unsigned long fileNo=0, int index=-1)
	Constructor. More...

	~Sample ()
	Destructor. More...

uint32_t	CalculateWaveDataChecksum ()

file_offset_t	GuessSize (file_offset_t samples)

file_offset_t	WorstCaseMaxSamples (buffer_t *pDecompressionBuffer)

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
Group *	pGroup
	pointer to the Group this sample belongs to (always not-NULL)

file_offset_t	FrameOffset
	Current offset (sample points) in current sample frame (for decompression only).

file_offset_t *	FrameTable
	For positioning within compressed samples only: stores the offset values for each frame.

file_offset_t	SamplePos
	For compressed samples only: stores the current position (in sample points).

file_offset_t	SamplesInLastFrame
	For compressed samples only: length of the last sample frame.

file_offset_t	WorstCaseFrameSize
	For compressed samples only: size (in bytes) of the largest possible sample frame.

file_offset_t	SamplesPerFrame
	For compressed samples only: number of samples in a full sample frame.

buffer_t	RAMCache
	Buffers samples (already uncompressed) in RAM.

unsigned long	FileNo
	File number (> 0 when sample is stored in an extension file, 0 when it's in the gig)

RIFF::Chunk *	pCk3gix

RIFF::Chunk *	pCkSmpl

uint32_t	crc
	Reflects CRC-32 checksum of the raw sample data at the last time when the sample's raw wave form data has been modified consciously by the user by calling Write().

RIFF::List *	pWaveList

RIFF::Chunk *	pCkData

RIFF::Chunk *	pCkFormat

file_offset_t	ullWavePoolOffset

Resource *	pParent

RIFF::List *	pResourceList

Static Protected Attributes
static size_t	Instances = 0
	Number of instances of class Sample.

static buffer_t	InternalDecompressionBuffer
	Buffer used for decompression of samples, and only if no external decompression buffer was supplied.

Detailed Description

Encapsulates sample waves of Gigasampler/GigaStudio files used for playback.

This class provides access to the actual audio sample data of a Gigasampler/GigaStudio file. Along to the actual sample data, it also provides access to the sample's meta informations like bit depth, sample rate, encoding type, but also loop informations. The latter may be used by instruments for resembling sounds with arbitary note lengths.

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, followed by File::Save(), this will create the mandatory RIFF chunk which will hold the sample wave data and / or resize the file so you will be able to Write() the sample data directly to disk.

Caution: for gig synthesis, most looping relevant information are retrieved from the respective DimensionRegon instead from the Sample itself. This was made for allowing different loop definitions for the same sample under different conditions.

Since the gig format was designed as extension to the DLS file format, this class is derived from the DLS::Sample class. So also refer to DLS::Sample for additional informations, class attributes and methods.

Definition at line 814 of file gig.h.

Constructor & Destructor Documentation

◆ Sample()

gig::Sample::Sample	(	File *	pFile,
		RIFF::List *	waveList,
		file_offset_t	WavePoolOffset,
		unsigned long	fileNo = `0`,
		int	index = `-1`
	)

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', 'data' (and optionally a '3gix', 'smpl') 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 gig::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
fileNo	- number of an extension file where this sample is located, 0 otherwise
index	- wave pool index of sample (may be -1 on new sample)

Definition at line 390 of file gig.cpp.

References DLS::Sample::BitDepth, DLS::Sample::Channels, Compressed, crc, Dithered, FileNo, FineTune, FrameOffset, FrameTable, gig::File::GetGroup(), RIFF::List::GetSubChunk(), Instances, InternalDecompressionBuffer, gig::loop_type_normal, LoopEnd, LoopFraction, LoopID, LoopPlayCount, Loops, LoopSize, LoopStart, LoopType, Manufacturer, MIDIUnityNote, gig::buffer_t::NullExtensionSize, pGroup, DLS::Resource::pInfo, Product, gig::buffer_t::pStart, RAMCache, RIFF::Chunk::Read(), RIFF::Chunk::ReadInt16(), RIFF::Chunk::ReadInt32(), SamplePeriod, SamplePos, DLS::Sample::SamplesPerSecond, DLS::Info::SetFixedStringLengths(), RIFF::Chunk::SetPos(), gig::buffer_t::Size, gig::smpte_format_no_offset, SMPTEFormat, SMPTEOffset, and TruncatedBits.

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

◆ ~Sample()

gig::Sample::~Sample ( )

protectedvirtual

Destructor.

Frees all memory occupied by this sample.

Reimplemented from DLS::Sample.

Definition at line 1477 of file gig.cpp.

References FrameTable, Instances, InternalDecompressionBuffer, gig::buffer_t::pStart, RAMCache, and gig::buffer_t::Size.

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 637 of file DLS.cpp.

References RIFF::List::GetSubChunk(), DLS::Resource::pInfo, RIFF::Chunk::Read(), RIFF::Chunk::ReadInt16(), RIFF::Chunk::ReadInt32(), RIFF::Chunk::ReadUint16(), RIFF::Chunk::ReadUint32(), and RIFF::Chunk::SetPos().

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

◆ CopyAssign() [2/2]

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

virtualinherited

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 917 of file DLS.cpp.

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

Referenced by gig::DimensionRegion::CopyAssign(), gig::Region::CopyAssign(), and gig::Instrument::CopyAssign().

◆ CopyAssignCore()

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

protectedinherited

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 897 of file DLS.cpp.

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

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

◆ CopyAssignMeta()

void gig::Sample::CopyAssignMeta ( const Sample * orig )

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

Discussion: copying .gig samples is a bit tricky. It requires three steps:

Copy sample's meta informations (done by CopyAssignMeta()) including its new sample waveform data size.
Saving the file (done by File::Save()) so that it gains correct size and layout for writing the actual wave form data directly to disc in next step.
Copy the waveform data with disk streaming (done by CopyAssignWave()).

Parameters

orig	- original Sample object to be copied from

Definition at line 510 of file gig.cpp.

References DLS::Sample::CopyAssignCore(), FineTune, DLS::Sample::GetSize(), LoopEnd, LoopFraction, LoopID, LoopPlayCount, Loops, LoopSize, LoopStart, LoopType, Manufacturer, MIDIUnityNote, Product, Resize(), SamplePeriod, SMPTEFormat, and SMPTEOffset.

Referenced by gig::File::AddContentOf().

◆ CopyAssignWave()

void gig::Sample::CopyAssignWave ( const Sample * orig )

Should be called after CopyAssignMeta() and File::Save() sequence.

Read more about it in the discussion of CopyAssignMeta(). This method copies the actual waveform data by disk streaming.

CAUTION: this method is currently not thread safe! During this operation the sample must not be used for other purposes by other threads!

Parameters

orig	- original Sample object to be copied from

Definition at line 546 of file gig.cpp.

References DLS::Sample::FrameSize, GetPos(), Read(), SetPos(), and Write().

◆ CreateDecompressionBuffer()

buffer_t gig::Sample::CreateDecompressionBuffer ( file_offset_t MaxReadSize )

static

Allocates a decompression buffer for streaming (compressed) samples with Sample::Read().

If you are using more than one streaming thread in your application you HAVE to create a decompression buffer for EACH of your streaming threads and provide it with the Sample::Read() call in order to avoid race conditions and crashes.

You should free the memory occupied by the allocated buffer(s) once you don't need one of your streaming threads anymore by calling DestroyDecompressionBuffer().

Parameters

MaxReadSize - the maximum size (in sample points) you ever expect to read with one Read() call

Returns: allocated decompression buffer

See also: DestroyDecompressionBuffer()

Definition at line 1373 of file gig.cpp.

References gig::buffer_t::NullExtensionSize, gig::buffer_t::pStart, and gig::buffer_t::Size.

◆ DeleteChunks()

void DLS::Sample::DeleteChunks ( )

virtualinherited

Remove all RIFF chunks associated with this Sample object.

See Storage::DeleteChunks() for details.

Reimplemented from DLS::Resource.

Definition at line 874 of file DLS.cpp.

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

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

◆ DestroyDecompressionBuffer()

void gig::Sample::DestroyDecompressionBuffer ( buffer_t & DecompressionBuffer )

static

Free decompression buffer, previously created with CreateDecompressionBuffer().

Parameters

DecompressionBuffer - previously allocated decompression buffer to free

Definition at line 1390 of file gig.cpp.

References gig::buffer_t::NullExtensionSize, gig::buffer_t::pStart, and gig::buffer_t::Size.

◆ GetCache()

buffer_t gig::Sample::GetCache ( )

Returns current cached sample points.

A buffer_t structure will be returned which contains address pointer to the begin of the cache and the size of the cached sample data in bytes. Use LoadSampleData() to cache a specific amount of sample points in RAM.

Returns: buffer_t structure with current cached sample points

See also: LoadSampleData();

Definition at line 814 of file gig.cpp.

References gig::buffer_t::NullExtensionSize, gig::buffer_t::pStart, RAMCache, and gig::buffer_t::Size.

Referenced by LoadSampleDataWithNullSamplesExtension().

◆ GetGroup()

Group * gig::Sample::GetGroup ( ) const

Returns pointer to the Group this Sample belongs to.

In the .gig format a sample always belongs to one group. If it wasn't explicitly assigned to a certain group, it will be automatically assigned to a default group.

Returns: Sample's Group (never NULL)

Definition at line 1407 of file gig.cpp.

References pGroup.

Referenced by gig::File::AddContentOf(), and gig::File::GetGroup().

◆ GetSize()

file_offset_t DLS::Sample::GetSize ( ) const

inherited

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 986 of file DLS.cpp.

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

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

◆ GetWaveDataCRC32Checksum()

uint32_t gig::Sample::GetWaveDataCRC32Checksum ( )

Returns the CRC-32 checksum of the sample's raw wave form data at the time when this sample's wave form data was modified for the last time by calling Write().

This checksum only covers the raw wave form data, not any meta informations like i.e. bit depth or loop points. Since this method just returns the checksum stored for this sample i.e. when the gig file was loaded, this method returns immediately. So it does no recalcuation of the checksum with the currently available sample wave form data.

See also: VerifyWaveData()

Definition at line 1423 of file gig.cpp.

References crc.

◆ LoadSampleData() [1/2]

buffer_t gig::Sample::LoadSampleData ( )

Loads (and uncompresses if needed) the whole sample wave into RAM.

Use ReleaseSampleData() to free the memory if you don't need the cached sample data anymore.

Returns: buffer_t structure with start address and size of the buffer in bytes

See also: ReleaseSampleData(), Read(), SetPos()

Definition at line 706 of file gig.cpp.

References LoadSampleDataWithNullSamplesExtension(), and DLS::Sample::SamplesTotal.

◆ LoadSampleData() [2/2]

buffer_t gig::Sample::LoadSampleData ( file_offset_t SampleCount )

Reads (uncompresses if needed) and caches the first SampleCount numbers of SamplePoints in RAM.

Use ReleaseSampleData() to free the memory space if you don't need the cached samples anymore. There is no guarantee that exactly SampleCount samples will be cached; this is not an error. The size will be eventually truncated e.g. to the beginning of a frame of a compressed sample. This is done for efficiency reasons while streaming the wave by your sampler engine later. Read the Size member of the buffer_t structure that will be returned to determine the actual cached samples, but note that the size is given in bytes! You get the number of actually cached samples by dividing it by the frame size of the sample:

buffer_t buf = pSample->LoadSampleData(acquired_samples);

long cachedsamples = buf.Size / pSample->FrameSize;

Parameters

SampleCount - number of sample points to load into RAM

Returns: buffer_t structure with start address and size of the cached sample data in bytes

See also: ReleaseSampleData(), Read(), SetPos()

Definition at line 732 of file gig.cpp.

References LoadSampleDataWithNullSamplesExtension().

◆ LoadSampleDataWithNullSamplesExtension() [1/2]

buffer_t gig::Sample::LoadSampleDataWithNullSamplesExtension ( uint NullSamplesCount )

Loads (and uncompresses if needed) the whole sample wave into RAM.

Use ReleaseSampleData() to free the memory if you don't need the cached sample data anymore. The method will add NullSamplesCount silence samples past the official buffer end (this won't affect the 'Size' member of the buffer_t structure, that means 'Size' always reflects the size of the actual sample data, the buffer might be bigger though). Silence samples past the official buffer are needed for differential algorithms that always have to take subsequent samples into account (resampling/interpolation would be an important example) and avoids memory access faults in such cases.

Parameters

NullSamplesCount - number of silence samples the buffer should be extended past it's data end

Returns: buffer_t structure with start address and size of the buffer in bytes

See also: ReleaseSampleData(), Read(), SetPos()

Definition at line 755 of file gig.cpp.

References DLS::Sample::SamplesTotal.

Referenced by LoadSampleData().

◆ LoadSampleDataWithNullSamplesExtension() [2/2]

buffer_t gig::Sample::LoadSampleDataWithNullSamplesExtension	(	file_offset_t	SampleCount,
		uint	NullSamplesCount
	)

Reads (uncompresses if needed) and caches the first SampleCount numbers of SamplePoints in RAM.

Use ReleaseSampleData() to free the memory space if you don't need the cached samples anymore. There is no guarantee that exactly SampleCount samples will be cached; this is not an error. The size will be eventually truncated e.g. to the beginning of a frame of a compressed sample. This is done for efficiency reasons while streaming the wave by your sampler engine later. Read the Size member of the buffer_t structure that will be returned to determine the actual cached samples, but note that the size is given in bytes! You get the number of actually cached samples by dividing it by the frame size of the sample:

buffer_t buf = pSample->LoadSampleDataWithNullSamplesExtension(acquired_samples, null_samples);

long cachedsamples = buf.Size / pSample->FrameSize;

The method will add NullSamplesCount silence samples past the official buffer end (this won't affect the 'Size' member of the buffer_t structure, that means 'Size' always reflects the size of the actual sample data, the buffer might be bigger though). Silence samples past the official buffer are needed for differential algorithms that always have to take subsequent samples into account (resampling/interpolation would be an important example) and avoids memory access faults in such cases.

Parameters

SampleCount	- number of sample points to load into RAM
NullSamplesCount	- number of silence samples the buffer should be extended past it's data end

Returns: buffer_t structure with start address and size of the cached sample data in bytes

See also: ReleaseSampleData(), Read(), SetPos()

Definition at line 791 of file gig.cpp.

References DLS::Sample::FrameSize, GetCache(), gig::buffer_t::NullExtensionSize, gig::buffer_t::pStart, RAMCache, Read(), DLS::Sample::SamplesTotal, SetPos(), and gig::buffer_t::Size.

◆ Read() [1/2]

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

inherited

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 1064 of file DLS.cpp.

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

Referenced by DLS::Sample::CopyAssign().

◆ Read() [2/2]

file_offset_t gig::Sample::Read	(	void *	pBuffer,
		file_offset_t	SampleCount,
		buffer_t *	pExternalDecompressionBuffer = `NULL`
	)

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

The sample wave stream will be decompressed on the fly if using a compressed sample. Use this method and SetPos() if you don't want to load the sample into RAM, thus for disk streaming.

Caution: If you are using more than one streaming thread, you have to use an external decompression buffer for EACH streaming thread to avoid race conditions and crashes!

For 16 bit samples, the data in the buffer will be int16_t (using native endianness). For 24 bit, the buffer will contain three bytes per sample, little-endian.

Parameters

pBuffer	destination buffer
SampleCount	number of sample points to read
pExternalDecompressionBuffer	(optional) external buffer to use for decompression

Returns: number of successfully read sample points

See also: SetPos(), CreateDecompressionBuffer()

Definition at line 1140 of file gig.cpp.

References DLS::Sample::BitDepth, DLS::Sample::Channels, Compressed, FrameOffset, DLS::Sample::FrameSize, InternalDecompressionBuffer, gig::buffer_t::pStart, RIFF::Chunk::Read(), RIFF::Chunk::RemainingBytes(), SamplePos, SamplesInLastFrame, SamplesPerFrame, DLS::Sample::SamplesTotal, RIFF::Chunk::SetPos(), gig::buffer_t::Size, and TruncatedBits.

Referenced by CopyAssignWave(), LoadSampleDataWithNullSamplesExtension(), ReadAndLoop(), and VerifyWaveData().

◆ ReadAndLoop()

file_offset_t gig::Sample::ReadAndLoop	(	void *	pBuffer,
		file_offset_t	SampleCount,
		playback_state_t *	pPlaybackState,
		DimensionRegion *	pDimRgn,
		buffer_t *	pExternalDecompressionBuffer = `NULL`
	)

Reads SampleCount number of sample points from the position stored in pPlaybackState into the buffer pointed by pBuffer and moves the position within the sample respectively, this method honors the looping informations of the sample (if any).

The sample wave stream will be decompressed on the fly if using a compressed sample. Use this method if you don't want to load the sample into RAM, thus for disk streaming. All this methods needs to know to proceed with streaming for the next time you call this method is stored in pPlaybackState. You have to allocate and initialize the playback_state_t structure by yourself before you use it to stream a sample:

gig::playback_state_t playbackstate;
playbackstate.position         = 0;
playbackstate.reverse          = false;
playbackstate.loop_cycles_left = pSample->LoopPlayCount;

You don't have to take care of things like if there is actually a loop defined or if the current read position is located within a loop area. The method already handles such cases by itself.

Caution: If you are using more than one streaming thread, you have to use an external decompression buffer for EACH streaming thread to avoid race conditions and crashes!

Parameters

pBuffer	destination buffer
SampleCount	number of sample points to read
pPlaybackState	will be used to store and reload the playback state for the next ReadAndLoop() call
pDimRgn	dimension region with looping information
pExternalDecompressionBuffer	(optional) external buffer to use for decompression

Returns: number of successfully read sample points

See also: CreateDecompressionBuffer()

Definition at line 965 of file gig.cpp.

References DLS::Sample::FrameSize, GetPos(), gig::playback_state_t::loop_cycles_left, gig::loop_type_backward, gig::loop_type_bidirectional, gig::loop_type_normal, DLS::sample_loop_t::LoopLength, LoopPlayCount, DLS::sample_loop_t::LoopStart, DLS::sample_loop_t::LoopType, gig::playback_state_t::position, DLS::Sampler::pSampleLoops, Read(), gig::playback_state_t::reverse, DLS::Sampler::SampleLoops, and SetPos().

◆ ReleaseSampleData()

void gig::Sample::ReleaseSampleData ( )

Frees the cached sample from RAM if loaded with LoadSampleData() previously.

See also: LoadSampleData();

Definition at line 829 of file gig.cpp.

References gig::buffer_t::NullExtensionSize, gig::buffer_t::pStart, RAMCache, and gig::buffer_t::Size.

◆ Resize()

void gig::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 (i.e. with 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

DLS::Excecption	if FormatTag != DLS_WAVE_FORMAT_PCM
DLS::Exception	if NewSize is less than 1 or unrealistic large
gig::Exception	if existing sample is compressed

See also: DLS::Sample::GetSize(), DLS::Sample::FrameSize, DLS::Sample::FormatTag, File::Save()

Definition at line 866 of file gig.cpp.

References Compressed, and DLS::Sample::Resize().

Referenced by CopyAssignMeta().

◆ SetPos()

file_offset_t gig::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.

Although the original Gigasampler engine doesn't allow positioning within compressed samples, I decided to implement it. Even though the Gigasampler format doesn't allow to define loops for compressed samples at the moment, positioning within compressed samples might be interesting for some sampler engines though. The only drawback about my decision is that it takes longer to load compressed gig Files on startup, because it's neccessary to scan the samples for some mandatory informations. But I think as it doesn't affect the runtime efficiency, nobody will have a problem with that.

Parameters

SampleCount	number of sample points to jump
Whence	optional: to which relation SampleCount refers to, if omited RIFF::stream_start is assumed

Returns: the new sample position

See also: Read()

Definition at line 892 of file gig.cpp.

References Compressed, FrameOffset, DLS::Sample::FrameSize, FrameTable, SamplePos, DLS::Sample::SamplesTotal, and RIFF::Chunk::SetPos().

Referenced by CopyAssignWave(), LoadSampleDataWithNullSamplesExtension(), ReadAndLoop(), and VerifyWaveData().

◆ UpdateChunks()

void gig::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.

Usually there is absolutely no need to call this method explicitly. It will be called automatically when File::Save() was called.

Parameters

pProgress - callback function for progress notification

Exceptions

DLS::Exception	if FormatTag != DLS_WAVE_FORMAT_PCM or no sample data was provided yet
gig::Exception	if there is any invalid sample setting

Reimplemented from DLS::Sample.

Definition at line 574 of file gig.cpp.

References RIFF::List::AddSubChunk(), DLS::Sample::BitDepth, DLS::Sample::Channels, Compressed, RIFF::List::DeleteSubChunk(), FineTune, DLS::Sample::FrameSize, FrameTable, RIFF::Chunk::GetPos(), RIFF::List::GetSubChunk(), RIFF::Chunk::LoadChunkData(), LoopEnd, LoopFraction, LoopID, LoopPlayCount, Loops, LoopStart, LoopType, Manufacturer, MIDIUnityNote, pGroup, Product, RIFF::Chunk::ReadUint8(), RIFF::Chunk::RemainingBytes(), SamplePeriod, SamplesInLastFrame, SamplesPerFrame, DLS::Sample::SamplesPerSecond, DLS::Sample::SamplesTotal, RIFF::Chunk::SetPos(), SMPTEFormat, SMPTEOffset, DLS::Sample::UpdateChunks(), and WorstCaseFrameSize.

◆ VerifyWaveData()

bool gig::Sample::VerifyWaveData ( uint32_t * pActually = NULL )

Checks the integrity of this sample's raw audio wave data.

Whenever a Sample's raw wave data is intentionally modified (i.e. by calling Write() and supplying the new raw audio wave form data) a CRC32 checksum is calculated and stored/updated for this sample, along to the sample's meta informations.

Now by calling this method the current raw audio wave data is checked against the already stored CRC32 check sum in order to check whether the sample data had been damaged unintentionally for some reason. Since by calling this method always the entire raw audio wave data has to be read, verifying all samples this way may take a long time accordingly. And that's also the reason why the sample integrity is not checked by default whenever a gig file is loaded. So this method must be called explicitly to fulfill this task.

Parameters

pActually - (optional) if provided, will be set to the actually calculated checksum of the current raw wave form data, you can get the expected checksum instead by calling GetWaveDataCRC32Checksum()

Returns: true if sample is OK or false if the sample is damaged

Exceptions

Exception if no checksum had been stored to disk for this sample yet, or on I/O issues

See also: GetWaveDataCRC32Checksum()

Definition at line 1452 of file gig.cpp.

References crc, DLS::Sample::FrameSize, Read(), and SetPos().

◆ Write()

file_offset_t gig::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().

Note: there is currently no support for writing compressed samples.

For 16 bit samples, the data in the source buffer should be int16_t (using native endianness). For 24 bit, the buffer should contain three bytes per sample, little-endian.

Parameters

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

Exceptions

DLS::Exception	if current sample size is too small
gig::Exception	if sample is compressed

See also: DLS::LoadSampleData()

Definition at line 1329 of file gig.cpp.

References DLS::Sample::BitDepth, DLS::Sample::Channels, Compressed, DLS::Sample::FrameSize, RIFF::Chunk::GetNewSize(), RIFF::Chunk::GetPos(), RIFF::Chunk::GetSize(), DLS::Sample::GetSize(), gig::File::SetSampleChecksum(), and RIFF::Chunk::Write().

Referenced by CopyAssignWave().

Member Data Documentation

◆ LoopSize

uint32_t gig::Sample::LoopSize

Caution: Use the respective fields in the DimensionRegion instead of this one! (Intended purpose: Length of the looping area [in sample points] which is equivalent to

LoopEnd - LoopStart

.)

Definition at line 828 of file gig.h.

Referenced by CopyAssignMeta(), and Sample().

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

Static Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ Sample()

◆ ~Sample()

Member Function Documentation

◆ CopyAssign() [1/2]

◆ CopyAssign() [2/2]

◆ CopyAssignCore()

◆ CopyAssignMeta()

◆ CopyAssignWave()

◆ CreateDecompressionBuffer()

◆ DeleteChunks()

◆ DestroyDecompressionBuffer()

◆ GetCache()

◆ GetGroup()

◆ GetSize()

◆ GetWaveDataCRC32Checksum()

◆ LoadSampleData() [1/2]

◆ LoadSampleData() [2/2]

◆ LoadSampleDataWithNullSamplesExtension() [1/2]

◆ LoadSampleDataWithNullSamplesExtension() [2/2]

◆ Read() [1/2]

◆ Read() [2/2]

◆ ReadAndLoop()

◆ ReleaseSampleData()

◆ Resize()

◆ SetPos()

◆ UpdateChunks()

◆ VerifyWaveData()

◆ Write()

Member Data Documentation

◆ LoopSize