flac/include/FLAC/stream_encoder.h
2002-11-19 06:21:36 +00:00

1041 lines
41 KiB
C

/* libFLAC - Free Lossless Audio Codec library
* Copyright (C) 2000,2001,2002 Josh Coalson
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifndef FLAC__STREAM_ENCODER_H
#define FLAC__STREAM_ENCODER_H
#include "export.h"
#include "format.h"
#include "stream_decoder.h"
#ifdef __cplusplus
extern "C" {
#endif
/** \file include/FLAC/stream_encoder.h
*
* \brief
* This module contains the functions which implement the stream
* encoder.
*
* See the detailed documentation in the
* \link flac_stream_encoder stream encoder \endlink module.
*/
/** \defgroup flac_encoder FLAC/ *_encoder.h: encoder interfaces
* \ingroup flac
*
* \brief
* This module describes the two encoder layers provided by libFLAC.
*
* For encoding FLAC streams, libFLAC provides two layers of access. The
* lowest layer is stream-level encoding, and the highest is file-level
* encoding. The interfaces are described in the \link flac_stream_encoder
* stream encoder \endlink and \link flac_file_encoder file encoder \endlink
* modules respectively. Typically you will choose the highest layer that
* your output source will support.
*
* The stream encoder relies on callbacks for writing the data and
* metadata. The file encoder provides these callbacks internally and you
* need only supply the filename.
*/
/** \defgroup flac_stream_encoder FLAC/stream_encoder.h: stream encoder interface
* \ingroup flac_encoder
*
* \brief
* This module contains the functions which implement the stream
* encoder.
*
* The basic usage of this encoder is as follows:
* - The program creates an instance of an encoder using
* FLAC__stream_encoder_new().
* - The program overrides the default settings and sets callbacks using
* FLAC__stream_encoder_set_*() functions.
* - The program initializes the instance to validate the settings and
* prepare for encoding using FLAC__stream_encoder_init().
* - The program calls FLAC__stream_encoder_process() or
* FLAC__stream_encoder_process_interleaved() to encode data, which
* subsequently calls the callbacks when there is encoder data ready
* to be written.
* - The program finishes the encoding with FLAC__stream_encoder_finish(),
* which causes the encoder to encode any data still in its input pipe,
* call the metadata callback with the final encoding statistics, and
* finally reset the encoder to the uninitialized state.
* - The instance may be used again or deleted with
* FLAC__stream_encoder_delete().
*
* In more detail, the stream encoder functions similarly to the
* \link flac_stream_decoder stream decoder \endlink, but has fewer
* callbacks and more options. Typically the user will create a new
* instance by calling FLAC__stream_encoder_new(), then set the necessary
* parameters and callbacks with FLAC__stream_encoder_set_*(), and
* initialize it by calling FLAC__stream_encoder_init().
*
* Unlike the decoders, the stream encoder has many options that can
* affect the speed and compression ratio. When setting these parameters
* you should have some basic knowledge of the format (see the
* <A HREF="../documentation.html#format">user-level documentation</A>
* or the <A HREF="../format.html">formal description</A>). The
* FLAC__stream_encoder_set_*() functions themselves do not validate the
* values as many are interdependent. The FLAC__stream_encoder_init()
* function will do this, so make sure to pay attention to the state
* returned by FLAC__stream_encoder_init() to make sure that it is
* FLAC__STREAM_ENCODER_OK. Any parameters that are not set before
* FLAC__stream_encoder_init() will take on the defaults from the
* constructor.
*
* The user must provide function pointers for the following callbacks:
*
* - Write callback - This function is called by the encoder anytime there
* is raw encoded data to write. It may include metadata mixed with
* encoded audio frames and the data is not guaranteed to be aligned on
* frame or metadata block boundaries.
* - Metadata callback - This function is called once at the end of
* encoding with the populated STREAMINFO structure. This is so file
* encoders can seek back to the beginning of the file and write the
* STREAMINFO block with the correct statistics after encoding (like
* minimum/maximum frame size).
*
* The call to FLAC__stream_encoder_init() currently will also immediately
* call the write callback several times, once with the \c fLaC signature,
* and once for each encoded metadata block.
*
* After initializing the instance, the user may feed audio data to the
* encoder in one of two ways:
*
* - Channel separate, through FLAC__stream_encoder_process() - The user
* will pass an array of pointers to buffers, one for each channel, to
* the encoder, each of the same length. The samples need not be
* block-aligned.
* - Channel interleaved, through
* FLAC__stream_encoder_process_interleaved() - The user will pass a single
* pointer to data that is channel-interleaved (i.e. channel0_sample0,
* channel1_sample0, ... , channelN_sample0, channel0_sample1, ...).
* Again, the samples need not be block-aligned but they must be
* sample-aligned, i.e. the first value should be channel0_sample0 and
* the last value channelN_sampleM.
*
* When the user is finished encoding data, it calls
* FLAC__stream_encoder_finish(), which causes the encoder to encode any
* data still in its input pipe, and call the metadata callback with the
* final encoding statistics. Then the instance may be deleted with
* FLAC__stream_encoder_delete() or initialized again to encode another
* stream.
*
* For programs that write their own metadata, but that do not know the
* actual metadata until after encoding, it is advantageous to instruct
* the encoder to write a PADDING block of the correct size, so that
* instead of rewriting the whole stream after encoding, the program can
* just overwrite the PADDING block. If only the maximum size of the
* metadata is known, the program can write a slightly larger padding
* block, then split it after encoding.
*
* Make sure you understand how lengths are calculated. All FLAC metadata
* blocks have a 4 byte header which contains the type and length. This
* length does not include the 4 bytes of the header. See the format page
* for the specification of metadata blocks and their lengths.
*
* \note
* The "set" functions may only be called when the encoder is in the
* state FLAC__STREAM_ENCODER_UNINITIALIZED, i.e. after
* FLAC__stream_encoder_new() or FLAC__stream_encoder_finish(), but
* before FLAC__stream_encoder_init(). If this is the case they will
* return \c true, otherwise \c false.
*
* \note
* FLAC__stream_encoder_finish() resets all settings to the constructor
* defaults, including the callbacks.
*
* \{
*/
/** State values for a FLAC__StreamEncoder
*
* The encoder's state can be obtained by calling FLAC__stream_encoder_get_state().
*/
typedef enum {
FLAC__STREAM_ENCODER_OK = 0,
/**< The encoder is in the normal OK state. */
FLAC__STREAM_ENCODER_VERIFY_DECODER_ERROR,
/**< An error occurred in the underlying verify stream decoder;
* check FLAC__stream_encoder_get_verify_decoder_state().
*/
FLAC__STREAM_ENCODER_VERIFY_MISMATCH_IN_AUDIO_DATA,
/**< The verify decoder detected a mismatch between the original
* audio signal and the decoded audio signal.
*/
FLAC__STREAM_ENCODER_INVALID_CALLBACK,
/**< The encoder was initialized before setting all the required callbacks. */
FLAC__STREAM_ENCODER_INVALID_NUMBER_OF_CHANNELS,
/**< The encoder has an invalid setting for number of channels. */
FLAC__STREAM_ENCODER_INVALID_BITS_PER_SAMPLE,
/**< The encoder has an invalid setting for bits-per-sample.
* FLAC supports 4-32 bps but the reference encoder currently supports
* only up to 24 bps.
*/
FLAC__STREAM_ENCODER_INVALID_SAMPLE_RATE,
/**< The encoder has an invalid setting for the input sample rate. */
FLAC__STREAM_ENCODER_INVALID_BLOCK_SIZE,
/**< The encoder has an invalid setting for the block size. */
FLAC__STREAM_ENCODER_INVALID_MAX_LPC_ORDER,
/**< The encoder has an invalid setting for the maximum LPC order. */
FLAC__STREAM_ENCODER_INVALID_QLP_COEFF_PRECISION,
/**< The encoder has an invalid setting for the precision of the quantized linear predictor coefficients. */
FLAC__STREAM_ENCODER_MID_SIDE_CHANNELS_MISMATCH,
/**< Mid/side coding was specified but the number of channels is not equal to 2. */
FLAC__STREAM_ENCODER_MID_SIDE_SAMPLE_SIZE_MISMATCH,
/**< Deprecated. */
FLAC__STREAM_ENCODER_ILLEGAL_MID_SIDE_FORCE,
/**< Loose mid/side coding was specified but mid/side coding was not. */
FLAC__STREAM_ENCODER_BLOCK_SIZE_TOO_SMALL_FOR_LPC_ORDER,
/**< The specified block size is less than the maximum LPC order. */
FLAC__STREAM_ENCODER_NOT_STREAMABLE,
/**< The encoder is bound to the "streamable subset" but other settings violate it. */
FLAC__STREAM_ENCODER_FRAMING_ERROR,
/**< An error occurred while writing the stream; usually, the write_callback returned an error. */
FLAC__STREAM_ENCODER_INVALID_METADATA,
/**< The metadata input to the encoder is invalid, in one of the following ways:
* - FLAC__stream_encoder_set_metadata() was called with a null pointer but a block count > 0
* - One of the metadata blocks contains an undefined type
* - It contains an illegal CUESHEET as checked by FLAC__format_cuesheet_is_legal()
* - It contains an illegal SEEKTABLE as checked by FLAC__format_seektable_is_legal()
* - It contains more than one SEEKTABLE block or more than one VORBIS_COMMENT block
*/
FLAC__STREAM_ENCODER_FATAL_ERROR_WHILE_ENCODING,
/**< An error occurred while writing the stream; usually, the write_callback returned an error. */
FLAC__STREAM_ENCODER_FATAL_ERROR_WHILE_WRITING,
/**< The write_callback returned an error. */
FLAC__STREAM_ENCODER_MEMORY_ALLOCATION_ERROR,
/**< Memory allocation failed. */
FLAC__STREAM_ENCODER_ALREADY_INITIALIZED,
/**< FLAC__stream_encoder_init() was called when the encoder was
* already initialized, usually because
* FLAC__stream_encoder_finish() was not called.
*/
FLAC__STREAM_ENCODER_UNINITIALIZED
/**< The encoder is in the uninitialized state. */
} FLAC__StreamEncoderState;
/** Maps a FLAC__StreamEncoderState to a C string.
*
* Using a FLAC__StreamEncoderState as the index to this array
* will give the string equivalent. The contents should not be modified.
*/
extern FLAC_API const char * const FLAC__StreamEncoderStateString[];
/** Return values for the FLAC__StreamEncoder write callback.
*/
typedef enum {
FLAC__STREAM_ENCODER_WRITE_STATUS_OK = 0,
/**< The write was OK and encoding can continue. */
FLAC__STREAM_ENCODER_WRITE_STATUS_FATAL_ERROR
/**< An unrecoverable error occurred. The encoder will return from the process call. */
} FLAC__StreamEncoderWriteStatus;
/** Maps a FLAC__StreamEncoderWriteStatus to a C string.
*
* Using a FLAC__StreamEncoderWriteStatus as the index to this array
* will give the string equivalent. The contents should not be modified.
*/
extern FLAC_API const char * const FLAC__StreamEncoderWriteStatusString[];
/***********************************************************************
*
* class FLAC__StreamEncoder
*
***********************************************************************/
struct FLAC__StreamEncoderProtected;
struct FLAC__StreamEncoderPrivate;
/** The opaque structure definition for the stream encoder type.
* See the \link flac_stream_encoder stream encoder module \endlink
* for a detailed description.
*/
typedef struct {
struct FLAC__StreamEncoderProtected *protected_; /* avoid the C++ keyword 'protected' */
struct FLAC__StreamEncoderPrivate *private_; /* avoid the C++ keyword 'private' */
} FLAC__StreamEncoder;
/** Signature for the write callback.
* See FLAC__stream_encoder_set_write_callback() for more info.
*
* \param encoder The encoder instance calling the callback.
* \param buffer An array of encoded data of length \a bytes.
* \param bytes The byte length of \a buffer.
* \param samples The number of samples encoded by \a buffer.
* \c 0 has a special meaning; see
* FLAC__stream_encoder_set_write_callback().
* \param current_frame The number of the current frame being encoded.
* \param client_data The callee's client data set through
* FLAC__stream_encoder_set_client_data().
* \retval FLAC__StreamDecoderWriteStatus
* The callee's return status.
*/
typedef FLAC__StreamEncoderWriteStatus (*FLAC__StreamEncoderWriteCallback)(const FLAC__StreamEncoder *encoder, const FLAC__byte buffer[], unsigned bytes, unsigned samples, unsigned current_frame, void *client_data);
/** Signature for the metadata callback.
* See FLAC__stream_encoder_set_metadata_callback() for more info.
*
* \param encoder The encoder instance calling the callback.
* \param metadata The final populated STREAMINFO block.
* \param client_data The callee's client data set through
* FLAC__stream_encoder_set_client_data().
*/
typedef void (*FLAC__StreamEncoderMetadataCallback)(const FLAC__StreamEncoder *encoder, const FLAC__StreamMetadata *metadata, void *client_data);
/***********************************************************************
*
* Class constructor/destructor
*
***********************************************************************/
/** Create a new stream encoder instance. The instance is created with
* default settings; see the individual FLAC__stream_encoder_set_*()
* functions for each setting's default.
*
* \retval FLAC__StreamEncoder*
* \c NULL if there was an error allocating memory, else the new instance.
*/
FLAC_API FLAC__StreamEncoder *FLAC__stream_encoder_new();
/** Free an encoder instance. Deletes the object pointed to by \a encoder.
*
* \param encoder A pointer to an existing encoder.
* \assert
* \code encoder != NULL \endcode
*/
FLAC_API void FLAC__stream_encoder_delete(FLAC__StreamEncoder *encoder);
/***********************************************************************
*
* Public class method prototypes
*
***********************************************************************/
/** Set the "verify" flag. If \c true, the encoder will verify it's own
* encoded output by feeding it through an internal decoder and comparing
* the original signal against the decoded signal. If a mismatch occurs,
* the process call will return \c false. Note that this will slow the
* encoding process by the extra time required for decoding and comparison.
*
* \default \c false
* \param encoder An encoder instance to set.
* \param value Flag value (see above).
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* \c false if the encoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_set_verify(FLAC__StreamEncoder *encoder, FLAC__bool value);
/** Set the "streamable subset" flag. If \c true, the encoder will comply
* with the subset (see the format specification) and will check the
* settings during FLAC__stream_encoder_init() to see if all settings
* comply. If \c false, the settings may take advantage of the full
* range that the format allows.
*
* Make sure you know what it entails before setting this to \c false.
*
* \default \c true
* \param encoder An encoder instance to set.
* \param value Flag value (see above).
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* \c false if the encoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_set_streamable_subset(FLAC__StreamEncoder *encoder, FLAC__bool value);
/** Set to \c true to enable mid-side encoding on stereo input. The
* number of channels must be 2. Set to \c false to use only
* independent channel coding.
*
* \default \c false
* \param encoder An encoder instance to set.
* \param value Flag value (see above).
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* \c false if the encoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_set_do_mid_side_stereo(FLAC__StreamEncoder *encoder, FLAC__bool value);
/** Set to \c true to enable adaptive switching between mid-side and
* left-right encoding on stereo input. The number of channels must
* be 2. Set to \c false to use exhaustive searching. In either
* case, the mid/side stereo setting must be \c true.
*
* \default \c false
* \param encoder An encoder instance to set.
* \param value Flag value (see above).
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* \c false if the encoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_set_loose_mid_side_stereo(FLAC__StreamEncoder *encoder, FLAC__bool value);
/** Set the number of channels to be encoded.
*
* \default \c 2
* \param encoder An encoder instance to set.
* \param value See above.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* \c false if the encoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_set_channels(FLAC__StreamEncoder *encoder, unsigned value);
/** Set the sample resolution of the input to be encoded.
*
* \warning
* Do not feed the encoder data that is wider than the value you
* set here or you will generate an invalid stream.
*
* \default \c 16
* \param encoder An encoder instance to set.
* \param value See above.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* \c false if the encoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_set_bits_per_sample(FLAC__StreamEncoder *encoder, unsigned value);
/** Set the sample rate (in Hz) of the input to be encoded.
*
* \default \c 44100
* \param encoder An encoder instance to set.
* \param value See above.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* \c false if the encoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_set_sample_rate(FLAC__StreamEncoder *encoder, unsigned value);
/** Set the blocksize to use while encoding.
*
* \default \c 1152
* \param encoder An encoder instance to set.
* \param value See above.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* \c false if the encoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_set_blocksize(FLAC__StreamEncoder *encoder, unsigned value);
/** Set the maximum LPC order, or \c 0 to use only the fixed predictors.
*
* \default \c 0
* \param encoder An encoder instance to set.
* \param value See above.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* \c false if the encoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_set_max_lpc_order(FLAC__StreamEncoder *encoder, unsigned value);
/** Set the precision, in bits, of the quantized linear predictor
* coefficients, or \c 0 to let the encoder select it based on the
* blocksize.
*
* \note
* In the current implementation, qlp_coeff_precision + bits_per_sample must
* be less than 32.
*
* \default \c 0
* \param encoder An encoder instance to set.
* \param value See above.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* \c false if the encoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_set_qlp_coeff_precision(FLAC__StreamEncoder *encoder, unsigned value);
/** Set to \c false to use only the specified quantized linear predictor
* coefficient precision, or \c true to search neighboring precision
* values and use the best one.
*
* \default \c false
* \param encoder An encoder instance to set.
* \param value See above.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* \c false if the encoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_set_do_qlp_coeff_prec_search(FLAC__StreamEncoder *encoder, FLAC__bool value);
/** Deprecated. Setting this value has no effect.
*
* \default \c false
* \param encoder An encoder instance to set.
* \param value See above.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* \c false if the encoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_set_do_escape_coding(FLAC__StreamEncoder *encoder, FLAC__bool value);
/** Set to \c false to let the encoder estimate the best model order
* based on the residual signal energy, or \c true to force the
* encoder to evaluate all order models and select the best.
*
* \default \c false
* \param encoder An encoder instance to set.
* \param value See above.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* \c false if the encoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_set_do_exhaustive_model_search(FLAC__StreamEncoder *encoder, FLAC__bool value);
/** Set the minimum partition order to search when coding the residual.
* This is used in tandem with
* FLAC__stream_encoder_set_max_residual_partition_order().
*
* The partition order determines the context size in the residual.
* The context size will be approximately <tt>blocksize / (2 ^ order)</tt>.
*
* Set both min and max values to \c 0 to force a single context,
* whose Rice parameter is based on the residual signal variance.
* Otherwise, set a min and max order, and the encoder will search
* all orders, using the mean of each context for its Rice parameter,
* and use the best.
*
* \default \c 0
* \param encoder An encoder instance to set.
* \param value See above.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* \c false if the encoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_set_min_residual_partition_order(FLAC__StreamEncoder *encoder, unsigned value);
/** Set the maximum partition order to search when coding the residual.
* This is used in tandem with
* FLAC__stream_encoder_set_min_residual_partition_order().
*
* The partition order determines the context size in the residual.
* The context size will be approximately <tt>blocksize / (2 ^ order)</tt>.
*
* Set both min and max values to \c 0 to force a single context,
* whose Rice parameter is based on the residual signal variance.
* Otherwise, set a min and max order, and the encoder will search
* all orders, using the mean of each context for its Rice parameter,
* and use the best.
*
* \default \c 0
* \param encoder An encoder instance to set.
* \param value See above.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* \c false if the encoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_set_max_residual_partition_order(FLAC__StreamEncoder *encoder, unsigned value);
/** Deprecated. Setting this value has no effect.
*
* \default \c 0
* \param encoder An encoder instance to set.
* \param value See above.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* \c false if the encoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_set_rice_parameter_search_dist(FLAC__StreamEncoder *encoder, unsigned value);
/** Set an estimate of the total samples that will be encoded.
* This is merely an estimate and may be set to \c 0 if unknown.
* This value will be written to the STREAMINFO block before encoding,
* and can remove the need for the caller to rewrite the value later
* if the value is known before encoding.
*
* \default \c 0
* \param encoder An encoder instance to set.
* \param value See above.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* \c false if the encoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_set_total_samples_estimate(FLAC__StreamEncoder *encoder, FLAC__uint64 value);
/** Set the metadata blocks to be emitted to the stream before encoding.
* A value of \c NULL, \c 0 implies no metadata; otherwise, supply an
* array of pointers to metadata blocks. The array is non-const since
* the encoder may need to change the \a is_last flag inside them.
* Otherwise, the encoder will not modify or free the blocks. It is up
* to the caller to free the metadata blocks after encoding.
*
* \note
* The encoder stores only the \a metadata pointer; the passed-in array
* must survive at least until after FLAC__stream_encoder_init() returns.
* Do not modify the array or free the blocks until then.
*
* \note
* The STREAMINFO block is always written and no STREAMINFO block may
* occur in the supplied array.
*
* \note
* By default the encoder does not create a SEEKTABLE. If one is supplied
* in the \a metadata array it will be written verbatim. However by itself
* this is not very useful as the user will not know the stream offsets for
* the seekpoints ahead of time. You must use the seekable stream encoder
* to generate a legal seektable
* (see FLAC__seekable_stream_encoder_set_metadata())
*
* \note
* A VORBIS_COMMENT block may be supplied. The vendor string in it
* will be ignored. libFLAC will use it's own vendor string. libFLAC
* will not modify the passed-in VORBIS_COMMENT's vendor string, it
* will simply write it's own into the stream. If no VORBIS_COMMENT
* block is present in the \a metadata array, libFLAC will write an
* empty one, containing only the vendor string.
*
* \default \c NULL, 0
* \param encoder An encoder instance to set.
* \param metadata See above.
* \param num_blocks See above.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* \c false if the encoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_set_metadata(FLAC__StreamEncoder *encoder, FLAC__StreamMetadata **metadata, unsigned num_blocks);
/** Set the write callback.
* The supplied function will be called by the encoder anytime there is raw
* encoded data ready to write. It may include metadata mixed with encoded
* audio frames and the data is not guaranteed to be aligned on frame or
* metadata block boundaries.
*
* The only duty of the callback is to write out the \a bytes worth of data
* in \a buffer to the current position in the output stream. The arguments
* \a samples and \a current_frame are purely informational. If \a samples
* is greater than \c 0, then \a current_frame will hold the current frame
* number that is being written; otherwise, the write callback is being called
* to write metadata.
*
* \note
* The callback is mandatory and must be set before initialization.
*
* \default \c NULL
* \param encoder An encoder instance to set.
* \param value See above.
* \assert
* \code encoder != NULL \endcode
* \code value != NULL \endcode
* \retval FLAC__bool
* \c false if the encoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_set_write_callback(FLAC__StreamEncoder *encoder, FLAC__StreamEncoderWriteCallback value);
/** Set the metadata callback.
* The supplied function will be called once at the end of encoding with
* the populated STREAMINFO structure. This is so file encoders can seek
* back to the beginning of the file and write the STREAMINFO block with
* the correct statistics after encoding (like minimum/maximum frame size
* and total samples).
*
* \note
* The callback is mandatory and must be set before initialization.
*
* \default \c NULL
* \param encoder An encoder instance to set.
* \param value See above.
* \assert
* \code encoder != NULL \endcode
* \code value != NULL \endcode
* \retval FLAC__bool
* \c false if the encoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_set_metadata_callback(FLAC__StreamEncoder *encoder, FLAC__StreamEncoderMetadataCallback value);
/** Set the client data to be passed back to callbacks.
* This value will be supplied to callbacks in their \a client_data
* argument.
*
* \default \c NULL
* \param encoder An encoder instance to set.
* \param value See above.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* \c false if the encoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_set_client_data(FLAC__StreamEncoder *encoder, void *value);
/** Get the current encoder state.
*
* \param encoder An encoder instance to query.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__StreamEncoderState
* The current encoder state.
*/
FLAC_API FLAC__StreamEncoderState FLAC__stream_encoder_get_state(const FLAC__StreamEncoder *encoder);
/** Get the state of the verify stream decoder.
* Useful when the stream encoder state is
* \c FLAC__STREAM_ENCODER_VERIFY_DECODER_ERROR.
*
* \param encoder An encoder instance to query.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__StreamDecoderState
* The verify stream decoder state.
*/
FLAC_API FLAC__StreamDecoderState FLAC__stream_encoder_get_verify_decoder_state(const FLAC__StreamEncoder *encoder);
/** Get the current encoder state as a C string.
* This version automatically resolves
* \c FLAC__STREAM_ENCODER_VERIFY_DECODER_ERROR by getting the
* verify decoder's state.
*
* \param encoder A encoder instance to query.
* \assert
* \code encoder != NULL \endcode
* \retval const char *
* The encoder state as a C string. Do not modify the contents.
*/
FLAC_API const char *FLAC__stream_encoder_get_resolved_state_string(const FLAC__StreamEncoder *encoder);
/** Get relevant values about the nature of a verify decoder error.
* Useful when the stream encoder state is
* \c FLAC__STREAM_ENCODER_VERIFY_DECODER_ERROR. The arguments should
* be addresses in which the stats will be returned, or NULL if value
* is not desired.
*
* \param encoder An encoder instance to query.
* \param absolute_sample The absolute sample number of the mismatch.
* \param frame_number The number of the frame in which the mismatch occurred.
* \param channel The channel in which the mismatch occurred.
* \param sample The number of the sample (relative to the frame) in
* which the mismatch occurred.
* \param expected The expected value for the sample in question.
* \param got The actual value returned by the decoder.
* \assert
* \code encoder != NULL \endcode
*/
FLAC_API void FLAC__stream_encoder_get_verify_decoder_error_stats(const FLAC__StreamEncoder *encoder, FLAC__uint64 *absolute_sample, unsigned *frame_number, unsigned *channel, unsigned *sample, FLAC__int32 *expected, FLAC__int32 *got);
/** Get the "verify" flag.
*
* \param encoder An encoder instance to query.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* See FLAC__stream_encoder_set_verify().
*/
FLAC_API FLAC__bool FLAC__stream_encoder_get_verify(const FLAC__StreamEncoder *encoder);
/** Get the "streamable subset" flag.
*
* \param encoder An encoder instance to query.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* See FLAC__stream_encoder_set_streamable_subset().
*/
FLAC_API FLAC__bool FLAC__stream_encoder_get_streamable_subset(const FLAC__StreamEncoder *encoder);
/** Get the "mid/side stereo coding" flag.
*
* \param encoder An encoder instance to query.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* See FLAC__stream_encoder_get_do_mid_side_stereo().
*/
FLAC_API FLAC__bool FLAC__stream_encoder_get_do_mid_side_stereo(const FLAC__StreamEncoder *encoder);
/** Get the "adaptive mid/side switching" flag.
*
* \param encoder An encoder instance to query.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* See FLAC__stream_encoder_set_loose_mid_side_stereo().
*/
FLAC_API FLAC__bool FLAC__stream_encoder_get_loose_mid_side_stereo(const FLAC__StreamEncoder *encoder);
/** Get the number of input channels being processed.
*
* \param encoder An encoder instance to query.
* \assert
* \code encoder != NULL \endcode
* \retval unsigned
* See FLAC__stream_encoder_set_channels().
*/
FLAC_API unsigned FLAC__stream_encoder_get_channels(const FLAC__StreamEncoder *encoder);
/** Get the input sample resolution setting.
*
* \param encoder An encoder instance to query.
* \assert
* \code encoder != NULL \endcode
* \retval unsigned
* See FLAC__stream_encoder_set_bits_per_sample().
*/
FLAC_API unsigned FLAC__stream_encoder_get_bits_per_sample(const FLAC__StreamEncoder *encoder);
/** Get the input sample rate setting.
*
* \param encoder An encoder instance to query.
* \assert
* \code encoder != NULL \endcode
* \retval unsigned
* See FLAC__stream_encoder_set_sample_rate().
*/
FLAC_API unsigned FLAC__stream_encoder_get_sample_rate(const FLAC__StreamEncoder *encoder);
/** Get the blocksize setting.
*
* \param encoder An encoder instance to query.
* \assert
* \code encoder != NULL \endcode
* \retval unsigned
* See FLAC__stream_encoder_set_blocksize().
*/
FLAC_API unsigned FLAC__stream_encoder_get_blocksize(const FLAC__StreamEncoder *encoder);
/** Get the maximum LPC order setting.
*
* \param encoder An encoder instance to query.
* \assert
* \code encoder != NULL \endcode
* \retval unsigned
* See FLAC__stream_encoder_set_max_lpc_order().
*/
FLAC_API unsigned FLAC__stream_encoder_get_max_lpc_order(const FLAC__StreamEncoder *encoder);
/** Get the quantized linear predictor coefficient precision setting.
*
* \param encoder An encoder instance to query.
* \assert
* \code encoder != NULL \endcode
* \retval unsigned
* See FLAC__stream_encoder_set_qlp_coeff_precision().
*/
FLAC_API unsigned FLAC__stream_encoder_get_qlp_coeff_precision(const FLAC__StreamEncoder *encoder);
/** Get the qlp coefficient precision search flag.
*
* \param encoder An encoder instance to query.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* See FLAC__stream_encoder_set_do_qlp_coeff_prec_search().
*/
FLAC_API FLAC__bool FLAC__stream_encoder_get_do_qlp_coeff_prec_search(const FLAC__StreamEncoder *encoder);
/** Get the "escape coding" flag.
*
* \param encoder An encoder instance to query.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* See FLAC__stream_encoder_set_do_escape_coding().
*/
FLAC_API FLAC__bool FLAC__stream_encoder_get_do_escape_coding(const FLAC__StreamEncoder *encoder);
/** Get the exhaustive model search flag.
*
* \param encoder An encoder instance to query.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__bool
* See FLAC__stream_encoder_set_do_exhaustive_model_search().
*/
FLAC_API FLAC__bool FLAC__stream_encoder_get_do_exhaustive_model_search(const FLAC__StreamEncoder *encoder);
/** Get the minimum residual partition order setting.
*
* \param encoder An encoder instance to query.
* \assert
* \code encoder != NULL \endcode
* \retval unsigned
* See FLAC__stream_encoder_set_min_residual_partition_order().
*/
FLAC_API unsigned FLAC__stream_encoder_get_min_residual_partition_order(const FLAC__StreamEncoder *encoder);
/** Get maximum residual partition order setting.
*
* \param encoder An encoder instance to query.
* \assert
* \code encoder != NULL \endcode
* \retval unsigned
* See FLAC__stream_encoder_set_max_residual_partition_order().
*/
FLAC_API unsigned FLAC__stream_encoder_get_max_residual_partition_order(const FLAC__StreamEncoder *encoder);
/** Get the Rice parameter search distance setting.
*
* \param encoder An encoder instance to query.
* \assert
* \code encoder != NULL \endcode
* \retval unsigned
* See FLAC__stream_encoder_set_rice_parameter_search_dist().
*/
FLAC_API unsigned FLAC__stream_encoder_get_rice_parameter_search_dist(const FLAC__StreamEncoder *encoder);
/** Get the previously set estimate of the total samples to be encoded.
* The encoder merely mimics back the value given to
* FLAC__stream_encoder_set_total_samples_estimate() since it has no
* other way of knowing how many samples the user will encode.
*
* \param encoder An encoder instance to set.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__uint64
* See FLAC__stream_encoder_get_total_samples_estimate().
*/
FLAC_API FLAC__uint64 FLAC__stream_encoder_get_total_samples_estimate(const FLAC__StreamEncoder *encoder);
/** Initialize the encoder instance.
* Should be called after FLAC__stream_encoder_new() and
* FLAC__stream_encoder_set_*() but before FLAC__stream_encoder_process()
* or FLAC__stream_encoder_process_interleaved(). Will set and return
* the encoder state, which will be FLAC__STREAM_ENCODER_OK if
* initialization succeeded.
*
* The call to FLAC__stream_encoder_init() currently will also immediately
* call the write callback several times, once with the \c fLaC signature,
* and once for each encoded metadata block.
*
* \param encoder An uninitialized encoder instance.
* \assert
* \code encoder != NULL \endcode
* \retval FLAC__StreamEncoderState
* \c FLAC__STREAM_ENCODER_OK if initialization was successful; see
* FLAC__StreamEncoderState for the meanings of other return values.
*/
FLAC_API FLAC__StreamEncoderState FLAC__stream_encoder_init(FLAC__StreamEncoder *encoder);
/** Finish the encoding process.
* Flushes the encoding buffer, releases resources, resets the encoder
* settings to their defaults, and returns the encoder state to
* FLAC__STREAM_ENCODER_UNINITIALIZED. Note that this can generate
* one or more write callbacks before returning, and will generate
* a metadata callback.
*
* In the event of a prematurely-terminated encode, it is not strictly
* necessary to call this immediately before FLAC__stream_encoder_delete()
* but it is good practice to match every FLAC__stream_encoder_init()
* with a FLAC__stream_encoder_finish().
*
* \param encoder An uninitialized encoder instance.
* \assert
* \code encoder != NULL \endcode
*/
FLAC_API void FLAC__stream_encoder_finish(FLAC__StreamEncoder *encoder);
/** Submit data for encoding.
* This version allows you to supply the input data via an array of
* pointers, each pointer pointing to an array of \a samples samples
* representing one channel. The samples need not be block-aligned,
* but each channel should have the same number of samples.
*
* \param encoder An initialized encoder instance in the OK state.
* \param buffer An array of pointers to each channel's signal.
* \param samples The number of samples in one channel.
* \assert
* \code encoder != NULL \endcode
* \code FLAC__stream_encoder_get_state(encoder) == FLAC__STREAM_ENCODER_OK \endcode
* \retval FLAC__bool
* \c true if successful, else \c false; in this case, check the
* encoder state with FLAC__stream_encoder_get_state() to see what
* went wrong.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_process(FLAC__StreamEncoder *encoder, const FLAC__int32 * const buffer[], unsigned samples);
/** Submit data for encoding.
* This version allows you to supply the input data where the channels
* are interleaved into a single array (i.e. channel0_sample0,
* channel1_sample0, ... , channelN_sample0, channel0_sample1, ...).
* The samples need not be block-aligned but they must be
* sample-aligned, i.e. the first value should be channel0_sample0
* and the last value channelN_sampleM.
*
* \param encoder An initialized encoder instance in the OK state.
* \param buffer An array of channel-interleaved data (see above).
* \param samples The number of samples in one channel, the same as for
* FLAC__stream_encoder_process(). For example, if
* encoding two channels, \c 1000 \a samples corresponds
* to a \a buffer of 2000 values.
* \assert
* \code encoder != NULL \endcode
* \code FLAC__stream_encoder_get_state(encoder) == FLAC__STREAM_ENCODER_OK \endcode
* \retval FLAC__bool
* \c true if successful, else \c false; in this case, check the
* encoder state with FLAC__stream_encoder_get_state() to see what
* went wrong.
*/
FLAC_API FLAC__bool FLAC__stream_encoder_process_interleaved(FLAC__StreamEncoder *encoder, const FLAC__int32 buffer[], unsigned samples);
/* \} */
#ifdef __cplusplus
}
#endif
#endif