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diff --git a/apps/codecs/libFLAC/include/FLAC/stream_decoder.h b/apps/codecs/libFLAC/include/FLAC/stream_decoder.h new file mode 100644 index 0000000..6cd59d4 --- /dev/null +++ b/apps/codecs/libFLAC/include/FLAC/stream_decoder.h @@ -0,0 +1,873 @@ +/* libFLAC - Free Lossless Audio Codec library + * Copyright (C) 2000,2001,2002,2003,2004,2005 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(); + +/** 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 an + * 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 |