1 /* libFLAC - Free Lossless Audio Codec library
2 * Copyright (C) 2000,2001,2002 Josh Coalson
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
14 * You should have received a copy of the GNU Library General Public
15 * License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
17 * Boston, MA 02111-1307, USA.
20 #ifndef FLAC__STREAM_ENCODER_H
21 #define FLAC__STREAM_ENCODER_H
24 #include "stream_decoder.h"
31 /** \file include/FLAC/stream_encoder.h
34 * This module contains the functions which implement the stream
37 * See the detailed documentation in the
38 * \link flac_stream_encoder stream encoder \endlink module.
41 /** \defgroup flac_encoder FLAC/ *_encoder.h: encoder interfaces
45 * This module describes the two encoder layers provided by libFLAC.
47 * For encoding FLAC streams, libFLAC provides two layers of access. The
48 * lowest layer is stream-level encoding, and the highest is file-level
49 * encoding. The interfaces are described in the \link flac_stream_encoder
50 * stream encoder \endlink and \link flac_file_encoder file encoder \endlink
51 * modules respectively. Typically you will choose the highest layer that
52 * your output source will support.
54 * The stream encoder relies on callbacks for writing the data and
55 * metadata. The file encoder provides these callbacks internally and you
56 * need only supply the filename.
59 /** \defgroup flac_stream_encoder FLAC/stream_encoder.h: stream encoder interface
60 * \ingroup flac_encoder
63 * This module contains the functions which implement the stream
66 * The basic usage of this encoder is as follows:
67 * - The program creates an instance of an encoder using
68 * FLAC__stream_encoder_new().
69 * - The program overrides the default settings and sets callbacks for
70 * writing and metadata reporting using
71 * FLAC__stream_encoder_set_*() functions.
72 * - The program initializes the instance to validate the settings and
73 * prepare for encoding using FLAC__stream_encoder_init().
74 * - The program calls FLAC__stream_encoder_process() or
75 * FLAC__stream_encoder_process_interleaved() to encode data, which
76 * subsequently calls the callbacks when there is encoder data ready
78 * - The program finishes the encoding with FLAC__stream_encoder_finish(),
79 * which causes the encoder to encode any data still in its input pipe,
80 * call the metadata callback with the final encoding statistics, and
81 * finally reset the encoder to the uninitialized state.
82 * - The instance may be used again or deleted with
83 * FLAC__stream_encoder_delete().
85 * In more detail, the stream encoder functions similarly to the
86 * \link flac_stream_decoder stream decoder \endlink, but has fewer
87 * callbacks and more options. Typically the user will create a new
88 * instance by calling FLAC__stream_encoder_new(), then set the necessary
89 * parameters and callbacks with FLAC__stream_encoder_set_*(), and
90 * initialize it by calling FLAC__stream_encoder_init().
92 * Unlike the decoders, the stream encoder has many options that can
93 * affect the speed and compression ratio. When setting these parameters
94 * you should have some basic knowledge of the format (see the
95 * <A HREF="../documentation.html#format">user-level documentation</A>
96 * or the <A HREF="../format.html">formal description</A>). The
97 * FLAC__stream_encoder_set_*() functions themselves do not validate the
98 * values as many are interdependent. The FLAC__stream_encoder_init()
99 * function will do this, so make sure to pay attention to the state
100 * returned by FLAC__stream_encoder_init() to make sure that it is
101 * FLAC__STREAM_ENCODER_OK. Any parameters that are not set before
102 * FLAC__stream_encoder_init() will take on the defaults from the
105 * The user must provide function pointers for the following callbacks:
107 * - Write callback - This function is called by the encoder anytime there
108 * is raw encoded data to write. It may include metadata mixed with
109 * encoded audio frames and the data is not guaranteed to be aligned on
110 * frame or metadata block boundaries.
111 * - Metadata callback - This function is called once at the end of
112 * encoding with the populated STREAMINFO structure. This is so file
113 * encoders can seek back to the beginning of the file and write the
114 * STREAMINFO block with the correct statistics after encoding (like
115 * minimum/maximum frame size).
117 * The call to FLAC__stream_encoder_init() currently will also immediately
118 * call the write callback several times, once with the \c fLaC signature,
119 * and once for each encoded metadata block.
121 * After initializing the instance, the user may feed audio data to the
122 * encoder in one of two ways:
124 * - Channel separate, through FLAC__stream_encoder_process() - The user
125 * will pass an array of pointers to buffers, one for each channel, to
126 * the encoder, each of the same length. The samples need not be
128 * - Channel interleaved, through
129 * FLAC__stream_encoder_process_interleaved() - The user will pass a single
130 * pointer to data that is channel-interleaved (i.e. channel0_sample0,
131 * channel1_sample0, ... , channelN_sample0, channel0_sample1, ...).
132 * Again, the samples need not be block-aligned but they must be
133 * sample-aligned, i.e. the first value should be channel0_sample0 and
134 * the last value channelN_sampleM.
136 * When the user is finished encoding data, it calls
137 * FLAC__stream_encoder_finish(), which causes the encoder to encode any
138 * data still in its input pipe, and call the metadata callback with the
139 * final encoding statistics. Then the instance may be deleted with
140 * FLAC__stream_encoder_delete() or initialized again to encode another
143 * For programs that write their own metadata, but that do not know the
144 * actual metadata until after encoding, it is advantageous to instruct
145 * the encoder to write a PADDING block of the correct size, so that
146 * instead of rewriting the whole stream after encoding, the program can
147 * just overwrite the PADDING block. If only the maximum size of the
148 * metadata is known, the program can write a slightly larger padding
149 * block, then split it after encoding.
151 * Make sure you understand how lengths are calculated. All FLAC metadata
152 * blocks have a 4 byte header which contains the type and length. This
153 * length does not include the 4 bytes of the header. See the format page
154 * for the specification of metadata blocks and their lengths.
157 * The "set" functions may only be called when the encoder is in the
158 * state FLAC__STREAM_ENCODER_UNINITIALIZED, i.e. after
159 * FLAC__stream_encoder_new() or FLAC__stream_encoder_finish(), but
160 * before FLAC__stream_encoder_init(). If this is the case they will
161 * return \c true, otherwise \c false.
164 * FLAC__stream_encoder_finish() resets all settings to the constructor
165 * defaults, including the callbacks.
171 /** State values for a FLAC__StreamEncoder
173 * The encoder's state can be obtained by calling FLAC__stream_encoder_get_state().
177 FLAC__STREAM_ENCODER_OK = 0,
178 /**< The encoder is in the normal OK state. */
180 FLAC__STREAM_ENCODER_VERIFY_DECODER_ERROR,
181 /**< An error occurred in the underlying verify stream decoder;
182 * check FLAC__stream_encoder_get_verify_decoder_state().
185 FLAC__STREAM_ENCODER_VERIFY_MISMATCH_IN_AUDIO_DATA,
186 /**< The verify decoder detected a mismatch between the original
187 * audio signal and the decoded audio signal.
190 FLAC__STREAM_ENCODER_INVALID_CALLBACK,
191 /**< The encoder was initialized before setting all the required callbacks. */
193 FLAC__STREAM_ENCODER_INVALID_NUMBER_OF_CHANNELS,
194 /**< The encoder has an invalid setting for number of channels. */
196 FLAC__STREAM_ENCODER_INVALID_BITS_PER_SAMPLE,
197 /**< The encoder has an invalid setting for bits-per-sample.
198 * FLAC supports 4-32 bps but the reference encoder currently supports
202 FLAC__STREAM_ENCODER_INVALID_SAMPLE_RATE,
203 /**< The encoder has an invalid setting for the input sample rate. */
205 FLAC__STREAM_ENCODER_INVALID_BLOCK_SIZE,
206 /**< The encoder has an invalid setting for the block size. */
208 FLAC__STREAM_ENCODER_INVALID_MAX_LPC_ORDER,
209 /**< The encoder has an invalid setting for the maximum LPC order. */
211 FLAC__STREAM_ENCODER_INVALID_QLP_COEFF_PRECISION,
212 /**< The encoder has an invalid setting for the precision of the quantized linear predictor coefficients. */
214 FLAC__STREAM_ENCODER_MID_SIDE_CHANNELS_MISMATCH,
215 /**< Mid/side coding was specified but the number of channels is not equal to 2. */
217 FLAC__STREAM_ENCODER_MID_SIDE_SAMPLE_SIZE_MISMATCH,
220 FLAC__STREAM_ENCODER_ILLEGAL_MID_SIDE_FORCE,
221 /**< Loose mid/side coding was specified but mid/side coding was not. */
223 FLAC__STREAM_ENCODER_BLOCK_SIZE_TOO_SMALL_FOR_LPC_ORDER,
224 /**< The specified block size is less than the maximum LPC order. */
226 FLAC__STREAM_ENCODER_NOT_STREAMABLE,
227 /**< The encoder is bound to the "streamable subset" but other settings violate it. */
229 FLAC__STREAM_ENCODER_FRAMING_ERROR,
230 /**< An error occurred while writing the stream; usually, the write_callback returned an error. */
232 FLAC__STREAM_ENCODER_INVALID_METADATA,
233 /**< The metadata input to the encoder is invalid, in one of the following ways:
234 * - FLAC__stream_encoder_set_metadata() was called with a null pointer but a block count > 0
235 * - It contains an illegal SEEKTABLE as checked by FLAC__format_seektable_is_legal()
236 * - It contains more than one SEEKTABLE block or more than one VORBIS_COMMENT block
239 FLAC__STREAM_ENCODER_FATAL_ERROR_WHILE_ENCODING,
240 /**< An error occurred while writing the stream; usually, the write_callback returned an error. */
242 FLAC__STREAM_ENCODER_FATAL_ERROR_WHILE_WRITING,
243 /**< The write_callback returned an error. */
245 FLAC__STREAM_ENCODER_MEMORY_ALLOCATION_ERROR,
246 /**< Memory allocation failed. */
248 FLAC__STREAM_ENCODER_ALREADY_INITIALIZED,
249 /**< FLAC__stream_encoder_init() was called when the encoder was
250 * already initialized, usually because
251 * FLAC__stream_encoder_finish() was not called.
254 FLAC__STREAM_ENCODER_UNINITIALIZED
255 /**< The encoder is in the uninitialized state. */
257 } FLAC__StreamEncoderState;
259 /** Maps a FLAC__StreamEncoderState to a C string.
261 * Using a FLAC__StreamEncoderState as the index to this array
262 * will give the string equivalent. The contents should not be modified.
264 extern const char * const FLAC__StreamEncoderStateString[];
266 /** Return values for the FLAC__StreamEncoder write callback.
270 FLAC__STREAM_ENCODER_WRITE_STATUS_OK = 0,
271 /**< The write was OK and encoding can continue. */
273 FLAC__STREAM_ENCODER_WRITE_STATUS_FATAL_ERROR
274 /**< An unrecoverable error occurred. The encoder will return from the process call. */
276 } FLAC__StreamEncoderWriteStatus;
278 /** Maps a FLAC__StreamEncoderWriteStatus to a C string.
280 * Using a FLAC__StreamEncoderWriteStatus as the index to this array
281 * will give the string equivalent. The contents should not be modified.
283 extern const char * const FLAC__StreamEncoderWriteStatusString[];
286 /***********************************************************************
288 * class FLAC__StreamEncoder
290 ***********************************************************************/
292 struct FLAC__StreamEncoderProtected;
293 struct FLAC__StreamEncoderPrivate;
294 /** The opaque structure definition for the stream encoder type.
295 * See the \link flac_stream_encoder stream encoder module \endlink
296 * for a detailed description.
299 struct FLAC__StreamEncoderProtected *protected_; /* avoid the C++ keyword 'protected' */
300 struct FLAC__StreamEncoderPrivate *private_; /* avoid the C++ keyword 'private' */
301 } FLAC__StreamEncoder;
303 /** Signature for the write callback.
304 * See FLAC__stream_encoder_set_write_callback() for more info.
306 * \param encoder The encoder instance calling the callback.
307 * \param buffer An array of encoded data of length \a bytes.
308 * \param bytes The byte length of \a buffer.
309 * \param samples The number of samples encoded by \a buffer.
310 * \c 0 has a special meaning; see
311 * FLAC__stream_encoder_set_write_callback().
312 * \param current_frame The number of the current frame being encoded.
313 * \param client_data The callee's client data set through
314 * FLAC__stream_encoder_set_client_data().
315 * \retval FLAC__StreamDecoderWriteStatus
316 * The callee's return status.
318 typedef FLAC__StreamEncoderWriteStatus (*FLAC__StreamEncoderWriteCallback)(const FLAC__StreamEncoder *encoder, const FLAC__byte buffer[], unsigned bytes, unsigned samples, unsigned current_frame, void *client_data);
320 /** Signature for the metadata callback.
321 * See FLAC__stream_encoder_set_metadata_callback() for more info.
323 * \param encoder The encoder instance calling the callback.
324 * \param metadata The final populated STREAMINFO block.
325 * \param client_data The callee's client data set through
326 * FLAC__stream_encoder_set_client_data().
328 typedef void (*FLAC__StreamEncoderMetadataCallback)(const FLAC__StreamEncoder *encoder, const FLAC__StreamMetadata *metadata, void *client_data);
331 /***********************************************************************
333 * Class constructor/destructor
335 ***********************************************************************/
337 /** Create a new stream encoder instance. The instance is created with
338 * default settings; see the individual FLAC__stream_encoder_set_*()
339 * functions for each setting's default.
341 * \retval FLAC__StreamEncoder*
342 * \c NULL if there was an error allocating memory, else the new instance.
344 FLAC__StreamEncoder *FLAC__stream_encoder_new();
346 /** Free an encoder instance. Deletes the object pointed to by \a encoder.
348 * \param encoder A pointer to an existing encoder.
350 * \code encoder != NULL \endcode
352 void FLAC__stream_encoder_delete(FLAC__StreamEncoder *encoder);
354 /***********************************************************************
356 * Public class method prototypes
358 ***********************************************************************/
360 /** Set the "verify" flag. If \c true, the encoder will verify it's own
361 * encoded output by feeding it through an internal decoder and comparing
362 * the original signal against the decoded signal. If a mismatch occurs,
363 * the process call will return \c false. Note that this will slow the
364 * encoding process by the extra time required for decoding and comparison.
367 * \param encoder An encoder instance to set.
368 * \param value Flag value (see above).
370 * \code encoder != NULL \endcode
372 * \c false if the encoder is already initialized, else \c true.
374 FLAC__bool FLAC__stream_encoder_set_verify(FLAC__StreamEncoder *encoder, FLAC__bool value);
376 /** Set the "streamable subset" flag. If \c true, the encoder will comply
377 * with the subset (see the format specification) and will check the
378 * settings during FLAC__stream_encoder_init() to see if all settings
379 * comply. If \c false, the settings may take advantage of the full
380 * range that the format allows.
382 * Make sure you know what it entails before setting this to \c false.
385 * \param encoder An encoder instance to set.
386 * \param value Flag value (see above).
388 * \code encoder != NULL \endcode
390 * \c false if the encoder is already initialized, else \c true.
392 FLAC__bool FLAC__stream_encoder_set_streamable_subset(FLAC__StreamEncoder *encoder, FLAC__bool value);
394 /** Set to \c true to enable mid-side encoding on stereo input. The
395 * number of channels must be 2. Set to \c false to use only
396 * independent channel coding.
399 * \param encoder An encoder instance to set.
400 * \param value Flag value (see above).
402 * \code encoder != NULL \endcode
404 * \c false if the encoder is already initialized, else \c true.
406 FLAC__bool FLAC__stream_encoder_set_do_mid_side_stereo(FLAC__StreamEncoder *encoder, FLAC__bool value);
408 /** Set to \c true to enable adaptive switching between mid-side and
409 * left-right encoding on stereo input. The number of channels must
410 * be 2. Set to \c false to use exhaustive searching. In either
411 * case, the mid/side stereo setting must be \c true.
414 * \param encoder An encoder instance to set.
415 * \param value Flag value (see above).
417 * \code encoder != NULL \endcode
419 * \c false if the encoder is already initialized, else \c true.
421 FLAC__bool FLAC__stream_encoder_set_loose_mid_side_stereo(FLAC__StreamEncoder *encoder, FLAC__bool value);
423 /** Set the number of channels to be encoded.
426 * \param encoder An encoder instance to set.
427 * \param value See above.
429 * \code encoder != NULL \endcode
431 * \c false if the encoder is already initialized, else \c true.
433 FLAC__bool FLAC__stream_encoder_set_channels(FLAC__StreamEncoder *encoder, unsigned value);
435 /** Set the sample resolution of the input to be encoded.
438 * Do not feed the encoder data that is wider than the value you
439 * set here or you will generate an invalid stream.
442 * \param encoder An encoder instance to set.
443 * \param value See above.
445 * \code encoder != NULL \endcode
447 * \c false if the encoder is already initialized, else \c true.
449 FLAC__bool FLAC__stream_encoder_set_bits_per_sample(FLAC__StreamEncoder *encoder, unsigned value);
451 /** Set the sample rate (in Hz) of the input to be encoded.
454 * \param encoder An encoder instance to set.
455 * \param value See above.
457 * \code encoder != NULL \endcode
459 * \c false if the encoder is already initialized, else \c true.
461 FLAC__bool FLAC__stream_encoder_set_sample_rate(FLAC__StreamEncoder *encoder, unsigned value);
463 /** Set the blocksize to use while encoding.
466 * \param encoder An encoder instance to set.
467 * \param value See above.
469 * \code encoder != NULL \endcode
471 * \c false if the encoder is already initialized, else \c true.
473 FLAC__bool FLAC__stream_encoder_set_blocksize(FLAC__StreamEncoder *encoder, unsigned value);
475 /** Set the maximum LPC order, or \c 0 to use only the fixed predictors.
478 * \param encoder An encoder instance to set.
479 * \param value See above.
481 * \code encoder != NULL \endcode
483 * \c false if the encoder is already initialized, else \c true.
485 FLAC__bool FLAC__stream_encoder_set_max_lpc_order(FLAC__StreamEncoder *encoder, unsigned value);
487 /** Set the precision, in bits, of the quantized linear predictor
488 * coefficients, or \c 0 to let the encoder select it based on the
492 * In the current implementation, qlp_coeff_precision + bits_per_sample must
496 * \param encoder An encoder instance to set.
497 * \param value See above.
499 * \code encoder != NULL \endcode
501 * \c false if the encoder is already initialized, else \c true.
503 FLAC__bool FLAC__stream_encoder_set_qlp_coeff_precision(FLAC__StreamEncoder *encoder, unsigned value);
505 /** Set to \c false to use only the specified quantized linear predictor
506 * coefficient precision, or \c true to search neighboring precision
507 * values and use the best one.
510 * \param encoder An encoder instance to set.
511 * \param value See above.
513 * \code encoder != NULL \endcode
515 * \c false if the encoder is already initialized, else \c true.
517 FLAC__bool FLAC__stream_encoder_set_do_qlp_coeff_prec_search(FLAC__StreamEncoder *encoder, FLAC__bool value);
519 /** Deprecated. Setting this value has no effect.
522 * \param encoder An encoder instance to set.
523 * \param value See above.
525 * \code encoder != NULL \endcode
527 * \c false if the encoder is already initialized, else \c true.
529 FLAC__bool FLAC__stream_encoder_set_do_escape_coding(FLAC__StreamEncoder *encoder, FLAC__bool value);
531 /** Set to \c false to let the encoder estimate the best model order
532 * based on the residual signal energy, or \c true to force the
533 * encoder to evaluate all order models and select the best.
536 * \param encoder An encoder instance to set.
537 * \param value See above.
539 * \code encoder != NULL \endcode
541 * \c false if the encoder is already initialized, else \c true.
543 FLAC__bool FLAC__stream_encoder_set_do_exhaustive_model_search(FLAC__StreamEncoder *encoder, FLAC__bool value);
545 /** Set the minimum partition order to search when coding the residual.
546 * This is used in tandem with
547 * FLAC__stream_encoder_set_max_residual_partition_order().
549 * The partition order determines the context size in the residual.
550 * The context size will be approximately <tt>blocksize / (2 ^ order)</tt>.
552 * Set both min and max values to \c 0 to force a single context,
553 * whose Rice parameter is based on the residual signal variance.
554 * Otherwise, set a min and max order, and the encoder will search
555 * all orders, using the mean of each context for its Rice parameter,
559 * \param encoder An encoder instance to set.
560 * \param value See above.
562 * \code encoder != NULL \endcode
564 * \c false if the encoder is already initialized, else \c true.
566 FLAC__bool FLAC__stream_encoder_set_min_residual_partition_order(FLAC__StreamEncoder *encoder, unsigned value);
568 /** Set the minimum partition order to search when coding the residual.
569 * This is used in tandem with
570 * FLAC__stream_encoder_set_min_residual_partition_order().
572 * The partition order determines the context size in the residual.
573 * The context size will be approximately <tt>blocksize / (2 ^ order)</tt>.
575 * Set both min and max values to \c 0 to force a single context,
576 * whose Rice parameter is based on the residual signal variance.
577 * Otherwise, set a min and max order, and the encoder will search
578 * all orders, using the mean of each context for its Rice parameter,
582 * \param encoder An encoder instance to set.
583 * \param value See above.
585 * \code encoder != NULL \endcode
587 * \c false if the encoder is already initialized, else \c true.
589 FLAC__bool FLAC__stream_encoder_set_max_residual_partition_order(FLAC__StreamEncoder *encoder, unsigned value);
591 /** Deprecated. Setting this value has no effect.
594 * \param encoder An encoder instance to set.
595 * \param value See above.
597 * \code encoder != NULL \endcode
599 * \c false if the encoder is already initialized, else \c true.
601 FLAC__bool FLAC__stream_encoder_set_rice_parameter_search_dist(FLAC__StreamEncoder *encoder, unsigned value);
603 /** Set an estimate of the total samples that will be encoded.
604 * This is merely an estimate and may be set to \c 0 if unknown.
605 * This value will be written to the STREAMINFO block before encoding,
606 * and can remove the need for the caller to rewrite the value later
607 * if the value is known before encoding.
610 * \param encoder An encoder instance to set.
611 * \param value See above.
613 * \code encoder != NULL \endcode
615 * \c false if the encoder is already initialized, else \c true.
617 FLAC__bool FLAC__stream_encoder_set_total_samples_estimate(FLAC__StreamEncoder *encoder, FLAC__uint64 value);
619 /** Set the metadata blocks to be emitted to the stream before encoding.
620 * A value of \c NULL, \c 0 implies no metadata; otherwise, supply an
621 * array of pointers to metadata blocks. The array is non-const since
622 * the encoder may need to change the \a is_last flag inside them.
623 * Otherwise, the encoder will not modify or free the blocks. It is up
624 * to the caller to free the metadata blocks after encoding.
627 * The encoder stores only the \a metadata pointer; the passed-in array
628 * must survive at least until after FLAC__stream_encoder_init() returns.
629 * Do not modify the array or free the blocks until then.
632 * The STREAMINFO block is always written and no STREAMINFO block may
633 * occur in the supplied array.
636 * A VORBIS_COMMENT block may be supplied. The vendor string in it
637 * will be ignored. libFLAC will use it's own vendor string. libFLAC
638 * will not modify the passed-in VORBIS_COMMENT's vendor string, it
639 * will simply write it's own into the stream. If no VORBIS_COMMENT
640 * block is present in the \a metadata array, libFLAC will write an
641 * empty one, containing only the vendor string.
643 * \default \c NULL, 0
644 * \param encoder An encoder instance to set.
645 * \param metadata See above.
646 * \param num_blocks See above.
648 * \code encoder != NULL \endcode
650 * \c false if the encoder is already initialized, else \c true.
652 FLAC__bool FLAC__stream_encoder_set_metadata(FLAC__StreamEncoder *encoder, FLAC__StreamMetadata **metadata, unsigned num_blocks);
654 /** Set the write callback.
655 * The supplied function will be called by the encoder anytime there is raw
656 * encoded data ready to write. It may include metadata mixed with encoded
657 * audio frames and the data is not guaranteed to be aligned on frame or
658 * metadata block boundaries.
660 * The only duty of the callback is to write out the \a bytes worth of data
661 * in \a buffer to the current position in the output stream. The arguments
662 * \a samples and \a current_frame are purely informational. If \a samples
663 * is greater than \c 0, then \a current_frame will hold the current frame
664 * number that is being written; otherwise, the write callback is being called
668 * The callback is mandatory and must be set before initialization.
671 * \param encoder An encoder instance to set.
672 * \param value See above.
674 * \code encoder != NULL \endcode
675 * \code value != NULL \endcode
677 * \c false if the encoder is already initialized, else \c true.
679 FLAC__bool FLAC__stream_encoder_set_write_callback(FLAC__StreamEncoder *encoder, FLAC__StreamEncoderWriteCallback value);
681 /** Set the metadata callback.
682 * The supplied function will be called once at the end of encoding with
683 * the populated STREAMINFO structure. This is so file encoders can seek
684 * back to the beginning of the file and write the STREAMINFO block with
685 * the correct statistics after encoding (like minimum/maximum frame size
686 * and total samples).
689 * The callback is mandatory and must be set before initialization.
692 * \param encoder An encoder instance to set.
693 * \param value See above.
695 * \code encoder != NULL \endcode
696 * \code value != NULL \endcode
698 * \c false if the encoder is already initialized, else \c true.
700 FLAC__bool FLAC__stream_encoder_set_metadata_callback(FLAC__StreamEncoder *encoder, FLAC__StreamEncoderMetadataCallback value);
702 /** Set the client data to be passed back to callbacks.
703 * This value will be supplied to callbacks in their \a client_data
707 * \param encoder An encoder instance to set.
708 * \param value See above.
710 * \code encoder != NULL \endcode
712 * \c false if the encoder is already initialized, else \c true.
714 FLAC__bool FLAC__stream_encoder_set_client_data(FLAC__StreamEncoder *encoder, void *value);
716 /** Get the current encoder state.
718 * \param encoder An encoder instance to query.
720 * \code encoder != NULL \endcode
721 * \retval FLAC__StreamEncoderState
722 * The current encoder state.
724 FLAC__StreamEncoderState FLAC__stream_encoder_get_state(const FLAC__StreamEncoder *encoder);
726 /** Get the state of the verify stream decoder.
727 * Useful when the stream encoder state is
728 * \c FLAC__STREAM_ENCODER_VERIFY_DECODER_ERROR.
730 * \param encoder An encoder instance to query.
732 * \code encoder != NULL \endcode
733 * \retval FLAC__StreamDecoderState
734 * The verify stream decoder state.
736 FLAC__StreamDecoderState FLAC__stream_encoder_get_verify_decoder_state(const FLAC__StreamEncoder *encoder);
738 /** Get relevant values about the nature of a verify decoder error.
739 * Useful when the stream encoder state is
740 * \c FLAC__STREAM_ENCODER_VERIFY_DECODER_ERROR. The arguments should
741 * be addresses in which the stats will be returned, or NULL if value
744 * \param encoder An encoder instance to query.
745 * \param absolute_sample The absolute sample number of the mismatch.
746 * \param frame_number The number of the frame in which the mismatch occurred.
747 * \param channel The channel in which the mismatch occurred.
748 * \param sample The number of the sample (relative to the frame) in
749 * which the mismatch occurred.
750 * \param expected The expected value for the sample in question.
751 * \param got The actual value returned by the decoder.
753 * \code encoder != NULL \endcode
755 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);
757 /** Get the "verify" flag.
759 * \param encoder An encoder instance to query.
761 * \code encoder != NULL \endcode
763 * See FLAC__stream_encoder_set_verify().
765 FLAC__bool FLAC__stream_encoder_get_verify(const FLAC__StreamEncoder *encoder);
767 /** Get the "streamable subset" flag.
769 * \param encoder An encoder instance to query.
771 * \code encoder != NULL \endcode
773 * See FLAC__stream_encoder_set_streamable_subset().
775 FLAC__bool FLAC__stream_encoder_get_streamable_subset(const FLAC__StreamEncoder *encoder);
777 /** Get the "mid/side stereo coding" flag.
779 * \param encoder An encoder instance to query.
781 * \code encoder != NULL \endcode
783 * See FLAC__stream_encoder_get_do_mid_side_stereo().
785 FLAC__bool FLAC__stream_encoder_get_do_mid_side_stereo(const FLAC__StreamEncoder *encoder);
787 /** Get the "adaptive mid/side switching" flag.
789 * \param encoder An encoder instance to query.
791 * \code encoder != NULL \endcode
793 * See FLAC__stream_encoder_set_loose_mid_side_stereo().
795 FLAC__bool FLAC__stream_encoder_get_loose_mid_side_stereo(const FLAC__StreamEncoder *encoder);
797 /** Get the number of input channels being processed.
799 * \param encoder An encoder instance to query.
801 * \code encoder != NULL \endcode
803 * See FLAC__stream_encoder_set_channels().
805 unsigned FLAC__stream_encoder_get_channels(const FLAC__StreamEncoder *encoder);
807 /** Get the input sample resolution setting.
809 * \param encoder An encoder instance to query.
811 * \code encoder != NULL \endcode
813 * See FLAC__stream_encoder_set_bits_per_sample().
815 unsigned FLAC__stream_encoder_get_bits_per_sample(const FLAC__StreamEncoder *encoder);
817 /** Get the input sample rate setting.
819 * \param encoder An encoder instance to query.
821 * \code encoder != NULL \endcode
823 * See FLAC__stream_encoder_set_sample_rate().
825 unsigned FLAC__stream_encoder_get_sample_rate(const FLAC__StreamEncoder *encoder);
827 /** Get the blocksize setting.
829 * \param encoder An encoder instance to query.
831 * \code encoder != NULL \endcode
833 * See FLAC__stream_encoder_set_blocksize().
835 unsigned FLAC__stream_encoder_get_blocksize(const FLAC__StreamEncoder *encoder);
837 /** Get the maximum LPC order setting.
839 * \param encoder An encoder instance to query.
841 * \code encoder != NULL \endcode
843 * See FLAC__stream_encoder_set_max_lpc_order().
845 unsigned FLAC__stream_encoder_get_max_lpc_order(const FLAC__StreamEncoder *encoder);
847 /** Get the quantized linear predictor coefficient precision setting.
849 * \param encoder An encoder instance to query.
851 * \code encoder != NULL \endcode
853 * See FLAC__stream_encoder_set_qlp_coeff_precision().
855 unsigned FLAC__stream_encoder_get_qlp_coeff_precision(const FLAC__StreamEncoder *encoder);
857 /** Get the qlp coefficient precision search flag.
859 * \param encoder An encoder instance to query.
861 * \code encoder != NULL \endcode
863 * See FLAC__stream_encoder_set_do_qlp_coeff_prec_search().
865 FLAC__bool FLAC__stream_encoder_get_do_qlp_coeff_prec_search(const FLAC__StreamEncoder *encoder);
867 /** Get the "escape coding" flag.
869 * \param encoder An encoder instance to query.
871 * \code encoder != NULL \endcode
873 * See FLAC__stream_encoder_set_do_escape_coding().
875 FLAC__bool FLAC__stream_encoder_get_do_escape_coding(const FLAC__StreamEncoder *encoder);
877 /** Get the exhaustive model search flag.
879 * \param encoder An encoder instance to query.
881 * \code encoder != NULL \endcode
883 * See FLAC__stream_encoder_set_do_exhaustive_model_search().
885 FLAC__bool FLAC__stream_encoder_get_do_exhaustive_model_search(const FLAC__StreamEncoder *encoder);
887 /** Get the minimum residual partition order setting.
889 * \param encoder An encoder instance to query.
891 * \code encoder != NULL \endcode
893 * See FLAC__stream_encoder_set_min_residual_partition_order().
895 unsigned FLAC__stream_encoder_get_min_residual_partition_order(const FLAC__StreamEncoder *encoder);
897 /** Get maximum residual partition order setting.
899 * \param encoder An encoder instance to query.
901 * \code encoder != NULL \endcode
903 * See FLAC__stream_encoder_set_max_residual_partition_order().
905 unsigned FLAC__stream_encoder_get_max_residual_partition_order(const FLAC__StreamEncoder *encoder);
907 /** Get the Rice parameter search distance setting.
909 * \param encoder An encoder instance to query.
911 * \code encoder != NULL \endcode
913 * See FLAC__stream_encoder_set_rice_parameter_search_dist().
915 unsigned FLAC__stream_encoder_get_rice_parameter_search_dist(const FLAC__StreamEncoder *encoder);
917 /** Get the previously set estimate of the total samples to be encoded.
918 * The encoder merely mimics back the value given to
919 * FLAC__stream_encoder_set_total_samples_estimate() since it has no
920 * other way of knowing how many samples the user will encode.
922 * \param encoder An encoder instance to set.
924 * \code encoder != NULL \endcode
925 * \retval FLAC__uint64
926 * See FLAC__stream_encoder_get_total_samples_estimate().
928 FLAC__uint64 FLAC__stream_encoder_get_total_samples_estimate(const FLAC__StreamEncoder *encoder);
930 /** Initialize the encoder instance.
931 * Should be called after FLAC__stream_encoder_new() and
932 * FLAC__stream_encoder_set_*() but before FLAC__stream_encoder_process()
933 * or FLAC__stream_encoder_process_interleaved(). Will set and return
934 * the encoder state, which will be FLAC__STREAM_ENCODER_OK if
935 * initialization succeeded.
937 * The call to FLAC__stream_encoder_init() currently will also immediately
938 * call the write callback several times, once with the \c fLaC signature,
939 * and once for each encoded metadata block.
941 * \param encoder An uninitialized encoder instance.
943 * \code encoder != NULL \endcode
944 * \retval FLAC__StreamEncoderState
945 * \c FLAC__STREAM_ENCODER_OK if initialization was successful; see
946 * FLAC__StreamEncoderState for the meanings of other return values.
948 FLAC__StreamEncoderState FLAC__stream_encoder_init(FLAC__StreamEncoder *encoder);
950 /** Finish the encoding process.
951 * Flushes the encoding buffer, releases resources, resets the encoder
952 * settings to their defaults, and returns the encoder state to
953 * FLAC__STREAM_ENCODER_UNINITIALIZED. Note that this can generate
954 * one or more write callbacks before returning, and will generate
955 * a metadata callback.
957 * In the event of a prematurely-terminated encode, it is not strictly
958 * necessary to call this immediately before FLAC__stream_encoder_delete()
959 * but it is good practice to match every FLAC__stream_encoder_init()
960 * with a FLAC__stream_encoder_finish().
962 * \param encoder An uninitialized encoder instance.
964 * \code encoder != NULL \endcode
966 void FLAC__stream_encoder_finish(FLAC__StreamEncoder *encoder);
968 /** Submit data for encoding.
969 * This version allows you to supply the input data via an array of
970 * pointers, each pointer pointing to an array of \a samples samples
971 * representing one channel. The samples need not be block-aligned,
972 * but each channel should have the same number of samples.
974 * \param encoder An initialized encoder instance in the OK state.
975 * \param buffer An array of pointers to each channel's signal.
976 * \param samples The number of samples in one channel.
978 * \code encoder != NULL \endcode
979 * \code FLAC__stream_encoder_get_state(encoder) == FLAC__STREAM_ENCODER_OK \endcode
981 * \c true if successful, else \c false; in this case, check the
982 * encoder state with FLAC__stream_encoder_get_state() to see what
985 FLAC__bool FLAC__stream_encoder_process(FLAC__StreamEncoder *encoder, const FLAC__int32 * const buffer[], unsigned samples);
987 /** Submit data for encoding.
988 * This version allows you to supply the input data where the channels
989 * are interleaved into a single array (i.e. channel0_sample0,
990 * channel1_sample0, ... , channelN_sample0, channel0_sample1, ...).
991 * The samples need not be block-aligned but they must be
992 * sample-aligned, i.e. the first value should be channel0_sample0
993 * and the last value channelN_sampleM.
995 * \param encoder An initialized encoder instance in the OK state.
996 * \param buffer An array of channel-interleaved data (see above).
997 * \param samples The number of samples in one channel, the same as for
998 * FLAC__stream_encoder_process(). For example, if
999 * encoding two channels, \c 1000 \a samples corresponds
1000 * to a \a buffer of 2000 values.
1002 * \code encoder != NULL \endcode
1003 * \code FLAC__stream_encoder_get_state(encoder) == FLAC__STREAM_ENCODER_OK \endcode
1004 * \retval FLAC__bool
1005 * \c true if successful, else \c false; in this case, check the
1006 * encoder state with FLAC__stream_encoder_get_state() to see what
1009 FLAC__bool FLAC__stream_encoder_process_interleaved(FLAC__StreamEncoder *encoder, const FLAC__int32 buffer[], unsigned samples);