ref: ccfb9118a3bf19a0a943b3a7bbfddd82cf4ddc5b
dir: /sys/src/cmd/audio/libFLAC/FLAC/stream_decoder.h/
/* libFLAC - Free Lossless Audio Codec library
* Copyright (C) 2000,2001,2002,2003,2004 Josh Coalson
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of the Xiph.org Foundation nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef FLAC__STREAM_DECODER_H
#define FLAC__STREAM_DECODER_H
#include "export.h"
#include "format.h"
#ifdef __cplusplus
extern "C" {
#endif
/** \file include/FLAC/stream_decoder.h
*
* \brief
* This module contains the functions which implement the stream
* decoder.
*
* See the detailed documentation in the
* \link flac_stream_decoder stream decoder \endlink module.
*/
/** \defgroup flac_decoder FLAC/ *_decoder.h: decoder interfaces
* \ingroup flac
*
* \brief
* This module describes the three decoder layers provided by libFLAC.
*
* For decoding FLAC streams, libFLAC provides three layers of access. The
* lowest layer is non-seekable stream-level decoding, the next is seekable
* stream-level decoding, and the highest layer is file-level decoding. The
* interfaces are described in the \link flac_stream_decoder stream decoder
* \endlink, \link flac_seekable_stream_decoder seekable stream decoder
* \endlink, and \link flac_file_decoder file decoder \endlink modules
* respectively. Typically you will choose the highest layer that your input
* source will support.
*
* The stream decoder relies on callbacks for all input and output and has no
* provisions for seeking. The seekable stream decoder wraps the stream
* decoder and exposes functions for seeking. However, you must provide
* extra callbacks for seek-related operations on your stream, like seek and
* tell. The file decoder wraps the seekable stream decoder and supplies
* most of the callbacks internally, simplifying the processing of standard
* files.
*/
/** \defgroup flac_stream_decoder FLAC/stream_decoder.h: stream decoder interface
* \ingroup flac_decoder
*
* \brief
* This module contains the functions which implement the stream
* decoder.
*
* The basic usage of this decoder is as follows:
* - The program creates an instance of a decoder using
* FLAC__stream_decoder_new().
* - The program overrides the default settings and sets callbacks for
* reading, writing, error reporting, and metadata reporting using
* FLAC__stream_decoder_set_*() functions.
* - The program initializes the instance to validate the settings and
* prepare for decoding using FLAC__stream_decoder_init().
* - The program calls the FLAC__stream_decoder_process_*() functions
* to decode data, which subsequently calls the callbacks.
* - The program finishes the decoding with FLAC__stream_decoder_finish(),
* which flushes the input and output and resets the decoder to the
* uninitialized state.
* - The instance may be used again or deleted with
* FLAC__stream_decoder_delete().
*
* In more detail, the program will create a new instance by calling
* FLAC__stream_decoder_new(), then call FLAC__stream_decoder_set_*()
* functions to set the callbacks and client data, and call
* FLAC__stream_decoder_init(). The required callbacks are:
*
* - Read callback - This function will be called when the decoder needs
* more input data. The address of the buffer to be filled is supplied,
* along with the number of bytes the buffer can hold. The callback may
* choose to supply less data and modify the byte count but must be careful
* not to overflow the buffer. The callback then returns a status code
* chosen from FLAC__StreamDecoderReadStatus.
* - Write callback - This function will be called when the decoder has
* decoded a single frame of data. The decoder will pass the frame
* metadata as well as an array of pointers (one for each channel)
* pointing to the decoded audio.
* - Metadata callback - This function will be called when the decoder has
* decoded a metadata block. In a valid FLAC file there will always be
* one STREAMINFO block, followed by zero or more other metadata
* blocks. These will be supplied by the decoder in the same order as
* they appear in the stream and always before the first audio frame
* (i.e. write callback). The metadata block that is passed in must not
* be modified, and it doesn't live beyond the callback, so you should
* make a copy of it with FLAC__metadata_object_clone() if you will need
* it elsewhere. Since metadata blocks can potentially be large, by
* default the decoder only calls the metadata callback for the STREAMINFO
* block; you can instruct the decoder to pass or filter other blocks with
* FLAC__stream_decoder_set_metadata_*() calls.
* - Error callback - This function will be called whenever an error occurs
* during decoding.
*
* Once the decoder is initialized, your program will call one of several
* functions to start the decoding process:
*
* - FLAC__stream_decoder_process_single() - Tells the decoder to process at
* most one metadata block or audio frame and return, calling either the
* metadata callback or write callback, respectively, once. If the decoder
* loses sync it will return with only the error callback being called.
* - FLAC__stream_decoder_process_until_end_of_metadata() - Tells the decoder
* to process the stream from the current location and stop upon reaching
* the first audio frame. The user will get one metadata, write, or error
* callback per metadata block, audio frame, or sync error, respectively.
* - FLAC__stream_decoder_process_until_end_of_stream() - Tells the decoder
* to process the stream from the current location until the read callback
* returns FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM or
* FLAC__STREAM_DECODER_READ_STATUS_ABORT. The user will get one metadata,
* write, or error callback per metadata block, audio frame, or sync error,
* respectively.
*
* When the decoder has finished decoding (normally or through an abort),
* the instance is finished by calling FLAC__stream_decoder_finish(), which
* ensures the decoder is in the correct state and frees memory. Then the
* instance may be deleted with FLAC__stream_decoder_delete() or initialized
* again to decode another stream.
*
* Note that the stream decoder has no real concept of stream position, it
* just converts data. To seek within a stream the callbacks have only to
* flush the decoder using FLAC__stream_decoder_flush() and start feeding
* data from the new position through the read callback. The seekable
* stream decoder does just this.
*
* The FLAC__stream_decoder_set_metadata_*() functions deserve special
* attention. By default, the decoder only calls the metadata_callback for
* the STREAMINFO block. These functions allow you to tell the decoder
* explicitly which blocks to parse and return via the metadata_callback
* and/or which to skip. Use a FLAC__stream_decoder_set_metadata_respond_all(),
* FLAC__stream_decoder_set_metadata_ignore() ... or FLAC__stream_decoder_set_metadata_ignore_all(),
* FLAC__stream_decoder_set_metadata_respond() ... sequence to exactly specify which
* blocks to return. Remember that some metadata blocks can be big so
* filtering out the ones you don't use can reduce the memory requirements
* of the decoder. Also note the special forms
* FLAC__stream_decoder_set_metadata_respond_application(id) and
* FLAC__stream_decoder_set_metadata_ignore_application(id) for filtering APPLICATION
* blocks based on the application ID.
*
* STREAMINFO and SEEKTABLE blocks are always parsed and used internally, but
* they still can legally be filtered from the metadata_callback.
*
* \note
* The "set" functions may only be called when the decoder is in the
* state FLAC__STREAM_DECODER_UNINITIALIZED, i.e. after
* FLAC__stream_decoder_new() or FLAC__stream_decoder_finish(), but
* before FLAC__stream_decoder_init(). If this is the case they will
* return \c true, otherwise \c false.
*
* \note
* FLAC__stream_decoder_finish() resets all settings to the constructor
* defaults, including the callbacks.
*
* \{
*/
/** State values for a FLAC__StreamDecoder
*
* The decoder's state can be obtained by calling FLAC__stream_decoder_get_state().
*/
typedef enum {
FLAC__STREAM_DECODER_SEARCH_FOR_METADATA = 0,
/**< The decoder is ready to search for metadata. */
FLAC__STREAM_DECODER_READ_METADATA,
/**< The decoder is ready to or is in the process of reading metadata. */
FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC,
/**< The decoder is ready to or is in the process of searching for the frame sync code. */
FLAC__STREAM_DECODER_READ_FRAME,
/**< The decoder is ready to or is in the process of reading a frame. */
FLAC__STREAM_DECODER_END_OF_STREAM,
/**< The decoder has reached the end of the stream. */
FLAC__STREAM_DECODER_ABORTED,
/**< The decoder was aborted by the read callback. */
FLAC__STREAM_DECODER_UNPARSEABLE_STREAM,
/**< The decoder encountered reserved fields in use in the stream. */
FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR,
/**< An error occurred allocating memory. */
FLAC__STREAM_DECODER_ALREADY_INITIALIZED,
/**< FLAC__stream_decoder_init() was called when the decoder was
* already initialized, usually because
* FLAC__stream_decoder_finish() was not called.
*/
FLAC__STREAM_DECODER_INVALID_CALLBACK,
/**< FLAC__stream_decoder_init() was called without all callbacks being set. */
FLAC__STREAM_DECODER_UNINITIALIZED
/**< The decoder is in the uninitialized state. */
} FLAC__StreamDecoderState;
/** Maps a FLAC__StreamDecoderState to a C string.
*
* Using a FLAC__StreamDecoderState as the index to this array
* will give the string equivalent. The contents should not be modified.
*/
extern FLAC_API const char * const FLAC__StreamDecoderStateString[];
/** Return values for the FLAC__StreamDecoder read callback.
*/
typedef enum {
FLAC__STREAM_DECODER_READ_STATUS_CONTINUE,
/**< The read was OK and decoding can continue. */
FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM,
/**< The read was attempted at the end of the stream. */
FLAC__STREAM_DECODER_READ_STATUS_ABORT
/**< An unrecoverable error occurred. The decoder will return from the process call. */
} FLAC__StreamDecoderReadStatus;
/** Maps a FLAC__StreamDecoderReadStatus to a C string.
*
* Using a FLAC__StreamDecoderReadStatus as the index to this array
* will give the string equivalent. The contents should not be modified.
*/
extern FLAC_API const char * const FLAC__StreamDecoderReadStatusString[];
/** Return values for the FLAC__StreamDecoder write callback.
*/
typedef enum {
FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE,
/**< The write was OK and decoding can continue. */
FLAC__STREAM_DECODER_WRITE_STATUS_ABORT
/**< An unrecoverable error occurred. The decoder will return from the process call. */
} FLAC__StreamDecoderWriteStatus;
/** Maps a FLAC__StreamDecoderWriteStatus to a C string.
*
* Using a FLAC__StreamDecoderWriteStatus as the index to this array
* will give the string equivalent. The contents should not be modified.
*/
extern FLAC_API const char * const FLAC__StreamDecoderWriteStatusString[];
/** Possible values passed in to the FLAC__StreamDecoder error callback.
*/
typedef enum {
FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC,
/**< An error in the stream caused the decoder to lose synchronization. */
FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER,
/**< The decoder encountered a corrupted frame header. */
FLAC__STREAM_DECODER_ERROR_STATUS_FRAME_CRC_MISMATCH
/**< The frame's data did not match the CRC in the footer. */
} FLAC__StreamDecoderErrorStatus;
/** Maps a FLAC__StreamDecoderErrorStatus to a C string.
*
* Using a FLAC__StreamDecoderErrorStatus as the index to this array
* will give the string equivalent. The contents should not be modified.
*/
extern FLAC_API const char * const FLAC__StreamDecoderErrorStatusString[];
/***********************************************************************
*
* class FLAC__StreamDecoder
*
***********************************************************************/
struct FLAC__StreamDecoderProtected;
struct FLAC__StreamDecoderPrivate;
/** The opaque structure definition for the stream decoder type.
* See the \link flac_stream_decoder stream decoder module \endlink
* for a detailed description.
*/
typedef struct {
struct FLAC__StreamDecoderProtected *protected_; /* avoid the C++ keyword 'protected' */
struct FLAC__StreamDecoderPrivate *private_; /* avoid the C++ keyword 'private' */
} FLAC__StreamDecoder;
/** Signature for the read callback.
* See FLAC__stream_decoder_set_read_callback() for more info.
*
* \param decoder The decoder instance calling the callback.
* \param buffer A pointer to a location for the callee to store
* data to be decoded.
* \param bytes A pointer to the size of the buffer. On entry
* to the callback, it contains the maximum number
* of bytes that may be stored in \a buffer. The
* callee must set it to the actual number of bytes
* stored (0 in case of error or end-of-stream) before
* returning.
* \param client_data The callee's client data set through
* FLAC__stream_decoder_set_client_data().
* \retval FLAC__StreamDecoderReadStatus
* The callee's return status.
*/
typedef FLAC__StreamDecoderReadStatus (*FLAC__StreamDecoderReadCallback)(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], unsigned *bytes, void *client_data);
/** Signature for the write callback.
* See FLAC__stream_decoder_set_write_callback() for more info.
*
* \param decoder The decoder instance calling the callback.
* \param frame The description of the decoded frame. See
* FLAC__Frame.
* \param buffer An array of pointers to decoded channels of data.
* Each pointer will point to an array of signed
* samples of length \a frame->header.blocksize.
* Currently, the channel order has no meaning
* except for stereo streams; in this case channel
* 0 is left and 1 is right.
* \param client_data The callee's client data set through
* FLAC__stream_decoder_set_client_data().
* \retval FLAC__StreamDecoderWriteStatus
* The callee's return status.
*/
typedef FLAC__StreamDecoderWriteStatus (*FLAC__StreamDecoderWriteCallback)(const FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[], void *client_data);
/** Signature for the metadata callback.
* See FLAC__stream_decoder_set_metadata_callback() for more info.
*
* \param decoder The decoder instance calling the callback.
* \param metadata The decoded metadata block.
* \param client_data The callee's client data set through
* FLAC__stream_decoder_set_client_data().
*/
typedef void (*FLAC__StreamDecoderMetadataCallback)(const FLAC__StreamDecoder *decoder, const FLAC__StreamMetadata *metadata, void *client_data);
/** Signature for the error callback.
* See FLAC__stream_decoder_set_error_callback() for more info.
*
* \param decoder The decoder instance calling the callback.
* \param status The error encountered by the decoder.
* \param client_data The callee's client data set through
* FLAC__stream_decoder_set_client_data().
*/
typedef void (*FLAC__StreamDecoderErrorCallback)(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status, void *client_data);
/***********************************************************************
*
* Class constructor/destructor
*
***********************************************************************/
/** Create a new stream decoder instance. The instance is created with
* default settings; see the individual FLAC__stream_decoder_set_*()
* functions for each setting's default.
*
* \retval FLAC__StreamDecoder*
* \c NULL if there was an error allocating memory, else the new instance.
*/
FLAC_API FLAC__StreamDecoder *FLAC__stream_decoder_new(void);
/** Free a decoder instance. Deletes the object pointed to by \a decoder.
*
* \param decoder A pointer to an existing decoder.
* \assert
* \code decoder != NULL \endcode
*/
FLAC_API void FLAC__stream_decoder_delete(FLAC__StreamDecoder *decoder);
/***********************************************************************
*
* Public class method prototypes
*
***********************************************************************/
/** Set the read callback.
* The supplied function will be called when the decoder needs more input
* data. The address of the buffer to be filled is supplied, along with
* the number of bytes the buffer can hold. The callback may choose to
* supply less data and modify the byte count but must be careful not to
* overflow the buffer. The callback then returns a status code chosen
* from FLAC__StreamDecoderReadStatus.
*
* \note
* The callback is mandatory and must be set before initialization.
*
* \default \c NULL
* \param decoder A decoder instance to set.
* \param value See above.
* \assert
* \code decoder != NULL \endcode
* \code value != NULL \endcode
* \retval FLAC__bool
* \c false if the decoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_decoder_set_read_callback(FLAC__StreamDecoder *decoder, FLAC__StreamDecoderReadCallback value);
/** Set the write callback.
* The supplied function will be called when the decoder has decoded a
* single frame of data. The decoder will pass the frame metadata as
* well as an array of pointers (one for each channel) pointing to the
* decoded audio.
*
* \note
* The callback is mandatory and must be set before initialization.
*
* \default \c NULL
* \param decoder A decoder instance to set.
* \param value See above.
* \assert
* \code decoder != NULL \endcode
* \code value != NULL \endcode
* \retval FLAC__bool
* \c false if the decoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_decoder_set_write_callback(FLAC__StreamDecoder *decoder, FLAC__StreamDecoderWriteCallback value);
/** Set the metadata callback.
* The supplied function will be called when the decoder has decoded a metadata
* block. In a valid FLAC file there will always be one STREAMINFO block,
* followed by zero or more other metadata blocks. These will be supplied
* by the decoder in the same order as they appear in the stream and always
* before the first audio frame (i.e. write callback). The metadata block
* that is passed in must not be modified, and it doesn't live beyond the
* callback, so you should make a copy of it with
* FLAC__metadata_object_clone() if you will need it elsewhere. Since
* metadata blocks can potentially be large, by default the decoder only
* calls the metadata callback for the STREAMINFO block; you can instruct
* the decoder to pass or filter other blocks with
* FLAC__stream_decoder_set_metadata_*() calls.
*
* \note
* The callback is mandatory and must be set before initialization.
*
* \default \c NULL
* \param decoder A decoder instance to set.
* \param value See above.
* \assert
* \code decoder != NULL \endcode
* \code value != NULL \endcode
* \retval FLAC__bool
* \c false if the decoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_callback(FLAC__StreamDecoder *decoder, FLAC__StreamDecoderMetadataCallback value);
/** Set the error callback.
* The supplied function will be called whenever an error occurs during
* decoding.
*
* \note
* The callback is mandatory and must be set before initialization.
*
* \default \c NULL
* \param decoder A decoder instance to set.
* \param value See above.
* \assert
* \code decoder != NULL \endcode
* \code value != NULL \endcode
* \retval FLAC__bool
* \c false if the decoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_decoder_set_error_callback(FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorCallback 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 decoder A decoder instance to set.
* \param value See above.
* \assert
* \code decoder != NULL \endcode
* \retval FLAC__bool
* \c false if the decoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_decoder_set_client_data(FLAC__StreamDecoder *decoder, void *value);
/** Direct the decoder to pass on all metadata blocks of type \a type.
*
* \default By default, only the \c STREAMINFO block is returned via the
* metadata callback.
* \param decoder A decoder instance to set.
* \param type See above.
* \assert
* \code decoder != NULL \endcode
* \a type is valid
* \retval FLAC__bool
* \c false if the decoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond(FLAC__StreamDecoder *decoder, FLAC__MetadataType type);
/** Direct the decoder to pass on all APPLICATION metadata blocks of the
* given \a id.
*
* \default By default, only the \c STREAMINFO block is returned via the
* metadata callback.
* \param decoder A decoder instance to set.
* \param id See above.
* \assert
* \code decoder != NULL \endcode
* \code id != NULL \endcode
* \retval FLAC__bool
* \c false if the decoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond_application(FLAC__StreamDecoder *decoder, const FLAC__byte id[4]);
/** Direct the decoder to pass on all metadata blocks of any type.
*
* \default By default, only the \c STREAMINFO block is returned via the
* metadata callback.
* \param decoder A decoder instance to set.
* \assert
* \code decoder != NULL \endcode
* \retval FLAC__bool
* \c false if the decoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond_all(FLAC__StreamDecoder *decoder);
/** Direct the decoder to filter out all metadata blocks of type \a type.
*
* \default By default, only the \c STREAMINFO block is returned via the
* metadata callback.
* \param decoder A decoder instance to set.
* \param type See above.
* \assert
* \code decoder != NULL \endcode
* \a type is valid
* \retval FLAC__bool
* \c false if the decoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore(FLAC__StreamDecoder *decoder, FLAC__MetadataType type);
/** Direct the decoder to filter out all APPLICATION metadata blocks of
* the given \a id.
*
* \default By default, only the \c STREAMINFO block is returned via the
* metadata callback.
* \param decoder A decoder instance to set.
* \param id See above.
* \assert
* \code decoder != NULL \endcode
* \code id != NULL \endcode
* \retval FLAC__bool
* \c false if the decoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore_application(FLAC__StreamDecoder *decoder, const FLAC__byte id[4]);
/** Direct the decoder to filter out all metadata blocks of any type.
*
* \default By default, only the \c STREAMINFO block is returned via the
* metadata callback.
* \param decoder A decoder instance to set.
* \assert
* \code decoder != NULL \endcode
* \retval FLAC__bool
* \c false if the decoder is already initialized, else \c true.
*/
FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore_all(FLAC__StreamDecoder *decoder);
/** Get the current decoder state.
*
* \param decoder A decoder instance to query.
* \assert
* \code decoder != NULL \endcode
* \retval FLAC__StreamDecoderState
* The current decoder state.
*/
FLAC_API FLAC__StreamDecoderState FLAC__stream_decoder_get_state(const FLAC__StreamDecoder *decoder);
/** Get the current decoder state as a C string.
*
* \param decoder A decoder instance to query.
* \assert
* \code decoder != NULL \endcode
* \retval const char *
* The decoder state as a C string. Do not modify the contents.
*/
FLAC_API const char *FLAC__stream_decoder_get_resolved_state_string(const FLAC__StreamDecoder *decoder);
/** Get the current number of channels in the stream being decoded.
* Will only be valid after decoding has started and will contain the
* value from the most recently decoded frame header.
*
* \param decoder A decoder instance to query.
* \assert
* \code decoder != NULL \endcode
* \retval unsigned
* See above.
*/
FLAC_API unsigned FLAC__stream_decoder_get_channels(const FLAC__StreamDecoder *decoder);
/** Get the current channel assignment in the stream being decoded.
* Will only be valid after decoding has started and will contain the
* value from the most recently decoded frame header.
*
* \param decoder A decoder instance to query.
* \assert
* \code decoder != NULL \endcode
* \retval FLAC__ChannelAssignment
* See above.
*/
FLAC_API FLAC__ChannelAssignment FLAC__stream_decoder_get_channel_assignment(const FLAC__StreamDecoder *decoder);
/** Get the current sample resolution in the stream being decoded.
* Will only be valid after decoding has started and will contain the
* value from the most recently decoded frame header.
*
* \param decoder A decoder instance to query.
* \assert
* \code decoder != NULL \endcode
* \retval unsigned
* See above.
*/
FLAC_API unsigned FLAC__stream_decoder_get_bits_per_sample(const FLAC__StreamDecoder *decoder);
/** Get the current sample rate in Hz of the stream being decoded.
* Will only be valid after decoding has started and will contain the
* value from the most recently decoded frame header.
*
* \param decoder A decoder instance to query.
* \assert
* \code decoder != NULL \endcode
* \retval unsigned
* See above.
*/
FLAC_API unsigned FLAC__stream_decoder_get_sample_rate(const FLAC__StreamDecoder *decoder);
/** Get the current blocksize of the stream being decoded.
* Will only be valid after decoding has started and will contain the
* value from the most recently decoded frame header.
*
* \param decoder A decoder instance to query.
* \assert
* \code decoder != NULL \endcode
* \retval unsigned
* See above.
*/
FLAC_API unsigned FLAC__stream_decoder_get_blocksize(const FLAC__StreamDecoder *decoder);
/** Initialize the decoder instance.
* Should be called after FLAC__stream_decoder_new() and
* FLAC__stream_decoder_set_*() but before any of the
* FLAC__stream_decoder_process_*() functions. Will set and return the
* decoder state, which will be FLAC__STREAM_DECODER_SEARCH_FOR_METADATA
* if initialization succeeded.
*
* \param decoder An uninitialized decoder instance.
* \assert
* \code decoder != NULL \endcode
* \retval FLAC__StreamDecoderState
* \c FLAC__STREAM_DECODER_SEARCH_FOR_METADATA if initialization was
* successful; see FLAC__StreamDecoderState for the meanings of other
* return values.
*/
FLAC_API FLAC__StreamDecoderState FLAC__stream_decoder_init(FLAC__StreamDecoder *decoder);
/** Finish the decoding process.
* Flushes the decoding buffer, releases resources, resets the decoder
* settings to their defaults, and returns the decoder state to
* FLAC__STREAM_DECODER_UNINITIALIZED.
*
* In the event of a prematurely-terminated decode, it is not strictly
* necessary to call this immediately before FLAC__stream_decoder_delete()
* but it is good practice to match every FLAC__stream_decoder_init()
* with a FLAC__stream_decoder_finish().
*
* \param decoder An uninitialized decoder instance.
* \assert
* \code decoder != NULL \endcode
*/
FLAC_API void FLAC__stream_decoder_finish(FLAC__StreamDecoder *decoder);
/** Flush the stream input.
* The decoder's input buffer will be cleared and the state set to
* \c FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC.
*
* \param decoder A decoder instance.
* \assert
* \code decoder != NULL \endcode
* \retval FLAC__bool
* \c true if successful, else \c false if a memory allocation
* error occurs.
*/
FLAC_API FLAC__bool FLAC__stream_decoder_flush(FLAC__StreamDecoder *decoder);
/** Reset the decoding process.
* The decoder's input buffer will be cleared and the state set to
* \c FLAC__STREAM_DECODER_SEARCH_FOR_METADATA. This is similar to
* FLAC__stream_decoder_finish() except that the settings are
* preserved; there is no need to call FLAC__stream_decoder_init()
* before decoding again.
*
* \param decoder A decoder instance.
* \assert
* \code decoder != NULL \endcode
* \retval FLAC__bool
* \c true if successful, else \c false if a memory allocation
* error occurs.
*/
FLAC_API FLAC__bool FLAC__stream_decoder_reset(FLAC__StreamDecoder *decoder);
/** Decode one metadata block or audio frame.
* This version instructs the decoder to decode a either a single metadata
* block or a single frame and stop, unless the callbacks return a fatal
* error or the read callback returns
* \c FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM.
*
* As the decoder needs more input it will call the read callback.
* Depending on what was decoded, the metadata or write callback will be
* called with the decoded metadata block or audio frame, unless an error
* occurred. If the decoder loses sync it will call the error callback
* instead.
*
* Unless there is a fatal read error or end of stream, this function
* will return once one whole frame is decoded. In other words, if the
* stream is not synchronized or points to a corrupt frame header, the
* decoder will continue to try and resync until it gets to a valid
* frame, then decode one frame, then return. If the decoder points to
* frame whose frame CRC in the frame footer does not match the
* computed frame CRC, this function will issue a
* FLAC__STREAM_DECODER_ERROR_STATUS_FRAME_CRC_MISMATCH error to the
* error callback, and return, having decoded one complete, although
* corrupt, frame. (Such corrupted frames are sent as silence of the
* correct length to the write callback.)
*
* \param decoder An initialized decoder instance.
* \assert
* \code decoder != NULL \endcode
* \retval FLAC__bool
* \c false if any read or write error occurred (except
* \c FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC), else \c true;
* in any case, check the decoder state with
* FLAC__stream_decoder_get_state() to see what went wrong or to
* check for lost synchronization (a sign of stream corruption).
*/
FLAC_API FLAC__bool FLAC__stream_decoder_process_single(FLAC__StreamDecoder *decoder);
/** Decode until the end of the metadata.
* This version instructs the decoder to decode from the current position
* and continue until all the metadata has been read, or until the
* callbacks return a fatal error or the read callback returns
* \c FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM.
*
* As the decoder needs more input it will call the read callback.
* As each metadata block is decoded, the metadata callback will be called
* with the decoded metadata. If the decoder loses sync it will call the
* error callback.
*
* \param decoder An initialized decoder instance.
* \assert
* \code decoder != NULL \endcode
* \retval FLAC__bool
* \c false if any read or write error occurred (except
* \c FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC), else \c true;
* in any case, check the decoder state with
* FLAC__stream_decoder_get_state() to see what went wrong or to
* check for lost synchronization (a sign of stream corruption).
*/
FLAC_API FLAC__bool FLAC__stream_decoder_process_until_end_of_metadata(FLAC__StreamDecoder *decoder);
/** Decode until the end of the stream.
* This version instructs the decoder to decode from the current position
* and continue until the end of stream (the read callback returns
* \c FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM), or until the
* callbacks return a fatal error.
*
* As the decoder needs more input it will call the read callback.
* As each metadata block and frame is decoded, the metadata or write
* callback will be called with the decoded metadata or frame. If the
* decoder loses sync it will call the error callback.
*
* \param decoder An initialized decoder instance.
* \assert
* \code decoder != NULL \endcode
* \retval FLAC__bool
* \c false if any read or write error occurred (except
* \c FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC), else \c true;
* in any case, check the decoder state with
* FLAC__stream_decoder_get_state() to see what went wrong or to
* check for lost synchronization (a sign of stream corruption).
*/
FLAC_API FLAC__bool FLAC__stream_decoder_process_until_end_of_stream(FLAC__StreamDecoder *decoder);
/** Skip one audio frame.
* This version instructs the decoder to 'skip' a single frame and stop,
* unless the callbacks return a fatal error or the read callback returns
* \c FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM.
*
* The decoding flow is the same as what occurs when
* FLAC__stream_decoder_process_single() is called to process an audio
* frame, except that this function does not decode the parsed data into
* PCM or call the write callback. The integrity of the frame is still
* checked the same way as in the other process functions.
*
* This function will return once one whole frame is skipped, in the
* same way that FLAC__stream_decoder_process_single() will return once
* one whole frame is decoded.
*
* This function, when used from the higher FLAC__SeekableStreamDecoder
* layer, can be used in more quickly determining FLAC frame boundaries
* when decoding of the actual data is not needed, for example when a
* application is separating a FLAC stream into frames for editing or
* storing in a container. To do this, the application can use
* FLAC__seekable_stream_decoder_skip_single_frame() to quickly advance
* to the next frame, then use
* FLAC__seekable_stream_decoder_get_decode_position() to find the new
* frame boundary.
*
* This function should only be called when the stream has advanced
* past all the metadata, otherwise it will return \c false.
*
* \param decoder An initialized decoder instance not in a metadata
* state.
* \assert
* \code decoder != NULL \endcode
* \retval FLAC__bool
* \c false if any read or write error occurred (except
* \c FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC), or if the decoder
* is in the FLAC__STREAM_DECODER_SEARCH_FOR_METADATA or
* FLAC__STREAM_DECODER_READ_METADATA state, else \c true;
* in any case, check the decoder state with
* FLAC__stream_decoder_get_state() to see what went wrong or to
* check for lost synchronization (a sign of stream corruption).
*/
FLAC_API FLAC__bool FLAC__stream_decoder_skip_single_frame(FLAC__StreamDecoder *decoder);
/* \} */
#ifdef __cplusplus
}
#endif
#endif