ref: 38d6c5896319fd315200ed1e38dbb612d12a3f36
dir: /src/flac.c/
/*
* Sound Tools File Format: FLAC
*
* Support for FLAC input and rudimentary support for FLAC output.
*
* (c) 2006 robs@users.sourceforge.net
*
* See LICENSE file for further copyright information.
*/
#include "st_i.h"
#ifdef HAVE_LIBFLAC
#include <math.h>
#include <string.h>
#include <FLAC/all.h>
typedef struct
{
/* Info: */
unsigned bits_per_sample;
unsigned channels;
unsigned sample_rate;
unsigned total_samples;
/* Decode buffer: */
FLAC__int32 const * const * decoded_wide_samples;
unsigned number_of_wide_samples;
unsigned wide_sample_number;
FLAC__FileDecoder * flac;
FLAC__bool eof;
} Decoder;
assert_static(sizeof(Decoder) <= ST_MAX_FILE_PRIVSIZE, /* else */ Decoder__PRIVSIZE_too_big);
static void FLAC__decoder_metadata_callback(FLAC__FileDecoder const * const flac, FLAC__StreamMetadata const * const metadata, void * const client_data)
{
ft_t format = (ft_t) client_data;
Decoder * decoder = (Decoder *) format->priv;
(void) flac;
if (metadata->type == FLAC__METADATA_TYPE_STREAMINFO)
{
decoder->bits_per_sample = metadata->data.stream_info.bits_per_sample;
decoder->channels = metadata->data.stream_info.channels;
decoder->sample_rate = metadata->data.stream_info.sample_rate;
decoder->total_samples = metadata->data.stream_info.total_samples;
}
else if (metadata->type == FLAC__METADATA_TYPE_VORBIS_COMMENT)
{
int i;
int comment_size = 0;
if (metadata->data.vorbis_comment.num_comments == 0)
{
return;
}
if (format->comment != NULL)
{
st_warn("FLAC: multiple Vorbis comment block ignored");
return;
}
for (i = 0; i < metadata->data.vorbis_comment.num_comments; ++i)
{
comment_size += metadata->data.vorbis_comment.comments[i].length + 1;
}
if ((format->comment = (char *) calloc(comment_size, sizeof(char))) == NULL)
{
st_fail_errno(format, ST_ENOMEM, "FLAC: Could not allocate memory");
decoder->eof = true;
return;
}
for (i = 0; i < metadata->data.vorbis_comment.num_comments; ++i)
{
strcat(format->comment, (char const *) metadata->data.vorbis_comment.comments[i].entry);
if (i != metadata->data.vorbis_comment.num_comments - 1)
{
strcat(format->comment, "\n");
}
}
}
}
static void FLAC__decoder_error_callback(FLAC__FileDecoder const * const flac, FLAC__StreamDecoderErrorStatus const status, void * const client_data)
{
ft_t format = (ft_t) client_data;
(void) flac;
st_fail_errno(format, ST_EINVAL, "%s", FLAC__StreamDecoderErrorStatusString[status]);
}
static FLAC__StreamDecoderWriteStatus FLAC__frame_decode_callback(FLAC__FileDecoder const * const flac, FLAC__Frame const * const frame, FLAC__int32 const * const buffer[], void * const client_data)
{
ft_t format = (ft_t) client_data;
Decoder * decoder = (Decoder *) format->priv;
(void) flac;
if (frame->header.bits_per_sample != decoder->bits_per_sample || frame->header.channels != decoder->channels || frame->header.sample_rate != decoder->sample_rate)
{
st_fail_errno(format, ST_EINVAL, "FLAC ERROR: parameters differ between frame and header");
return FLAC__STREAM_DECODER_WRITE_STATUS_ABORT;
}
decoder->decoded_wide_samples = buffer;
decoder->number_of_wide_samples = frame->header.blocksize;
decoder->wide_sample_number = 0;
return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
}
static int st_format_start_read(ft_t const format)
{
Decoder * decoder = (Decoder *) format->priv;
memset(decoder, 0, sizeof(*decoder));
decoder->flac = FLAC__file_decoder_new();
if (decoder->flac == NULL)
{
st_fail_errno(format, ST_ENOMEM, "FLAC ERROR creating the decoder instance");
return ST_EOF;
}
FLAC__file_decoder_set_md5_checking(decoder->flac, true);
FLAC__file_decoder_set_filename(decoder->flac, format->filename);
FLAC__file_decoder_set_write_callback(decoder->flac, FLAC__frame_decode_callback);
FLAC__file_decoder_set_metadata_callback(decoder->flac, FLAC__decoder_metadata_callback);
FLAC__file_decoder_set_error_callback(decoder->flac, FLAC__decoder_error_callback);
FLAC__file_decoder_set_metadata_respond_all(decoder->flac);
FLAC__file_decoder_set_client_data(decoder->flac, format);
if (FLAC__file_decoder_init(decoder->flac) != FLAC__FILE_DECODER_OK)
{
st_fail_errno(format, ST_EHDR, "FLAC ERROR initialising decoder");
return ST_EOF;
}
if (!FLAC__file_decoder_process_until_end_of_metadata(decoder->flac))
{
st_fail_errno(format, ST_EHDR, "FLAC ERROR whilst decoding metadata");
return ST_EOF;
}
if (FLAC__file_decoder_get_state(decoder->flac) != FLAC__FILE_DECODER_OK && FLAC__file_decoder_get_state(decoder->flac) != FLAC__FILE_DECODER_END_OF_FILE)
{
st_fail_errno(format, ST_EHDR, "FLAC ERROR during metadata decoding");
return ST_EOF;
}
format->info.encoding = ST_ENCODING_FLAC;
format->info.rate = decoder->sample_rate;
format->info.size = decoder->bits_per_sample >> 3;
format->info.channels = decoder->channels;
format->length = decoder->total_samples * decoder->channels;
return ST_SUCCESS;
}
static st_ssize_t st_format_read(ft_t const format, st_sample_t * sampleBuffer, st_size_t const requested)
{
Decoder * decoder = (Decoder *) format->priv;
int actual = 0;
while (!decoder->eof && actual < requested)
{
if (decoder->wide_sample_number >= decoder->number_of_wide_samples)
{
FLAC__file_decoder_process_single(decoder->flac);
}
if (decoder->wide_sample_number >= decoder->number_of_wide_samples)
{
decoder->eof = true;
}
else
{
unsigned channel;
for (channel = 0; channel < decoder->channels; ++channel)
{
FLAC__int32 d = decoder->decoded_wide_samples[channel][decoder->wide_sample_number];
switch (decoder->bits_per_sample)
{
case 8: *sampleBuffer++ = ST_SIGNED_BYTE_TO_SAMPLE(d); break;
case 16: *sampleBuffer++ = ST_SIGNED_WORD_TO_SAMPLE(d); break;
case 24: *sampleBuffer++ = ST_SIGNED_24BIT_TO_SAMPLE(d); break;
case 32: *sampleBuffer++ = ST_SIGNED_DWORD_TO_SAMPLE(d); break;
}
++actual;
}
++decoder->wide_sample_number;
}
}
return actual;
}
static int st_format_stop_read(ft_t const format)
{
Decoder * decoder = (Decoder *) format->priv;
if (!FLAC__file_decoder_finish(decoder->flac) && decoder->eof)
{
st_warn("FLAC decoder MD5 checksum mismatch.");
}
FLAC__file_decoder_delete(decoder->flac);
return ST_SUCCESS;
}
typedef struct
{
/* Info: */
unsigned bits_per_sample;
/* Encode buffer: */
FLAC__int32 * decoded_samples;
unsigned number_of_samples;
FLAC__StreamEncoder * flac;
} Encoder;
assert_static(sizeof(Encoder) <= ST_MAX_FILE_PRIVSIZE, /* else */ Encoder__PRIVSIZE_too_big);
FLAC__StreamEncoderWriteStatus flac_stream_encoder_write_callback(FLAC__StreamEncoder const * const flac, const FLAC__byte buffer[], unsigned const bytes, unsigned const samples, unsigned const current_frame, void * const client_data)
{
ft_t const format = (ft_t) client_data;
(void) flac, (void) samples, (void) current_frame;
return st_writebuf(format, buffer, 1, bytes) == bytes ? FLAC__STREAM_ENCODER_WRITE_STATUS_OK : FLAC__STREAM_ENCODER_WRITE_STATUS_FATAL_ERROR;
}
void flac_stream_encoder_metadata_callback(FLAC__StreamEncoder const * encoder, FLAC__StreamMetadata const * metadata, void * client_data)
{
(void) encoder, (void) metadata, (void) client_data;
}
static int st_format_start_write(ft_t const format)
{
Encoder * encoder = (Encoder *) format->priv;
FLAC__StreamEncoderState status;
memset(encoder, 0, sizeof(*encoder));
encoder->flac = FLAC__stream_encoder_new();
encoder->decoded_samples = malloc(ST_BUFSIZ * sizeof(FLAC__int32));
if (encoder->flac == NULL || encoder->decoded_samples == NULL)
{
st_fail_errno(format, ST_ENOMEM, "FLAC ERROR creating the encoder instance");
return ST_EOF;
}
{ /* Select and set FLAC encoder options: */
static struct
{
int blocksize;
FLAC__bool do_exhaustive_model_search;
FLAC__bool do_mid_side_stereo;
FLAC__bool loose_mid_side_stereo;
unsigned max_lpc_order;
int max_residual_partition_order;
int min_residual_partition_order;
} const options[] = {
{1152, false, false, false, 0, 2, 2},
{1152, false, true, true, 0, 2, 2},
{1152, false, true, false, 0, 3, 0},
{4608, false, false, false, 6, 3, 3},
{4608, false, true, true, 8, 3, 3},
{4608, false, true, false, 8, 3, 3},
{4608, false, true, false, 8, 4, 0},
{4608, true, true, false, 8, 6, 0},
{4608, true, true, false, 12, 6, 0},
};
unsigned compression_level = array_length(options) - 1; /* Default to "best" */
if (format->info.compression != HUGE_VAL)
{
compression_level = format->info.compression;
if (compression_level != format->info.compression ||
compression_level >= array_length(options))
{
st_fail_errno(format, ST_EINVAL,
"FLAC compression level must be a whole number from 0 to %i",
array_length(options) - 1);
return ST_EOF;
}
}
#define SET_OPTION(x) do {\
st_report("FLAC "#x" = %i", options[compression_level].x); \
FLAC__stream_encoder_set_##x(encoder->flac, options[compression_level].x);\
} while (0)
SET_OPTION(blocksize);
SET_OPTION(do_exhaustive_model_search);
SET_OPTION(max_lpc_order);
SET_OPTION(max_residual_partition_order);
SET_OPTION(min_residual_partition_order);
if (format->info.channels == 2)
{
SET_OPTION(do_mid_side_stereo);
SET_OPTION(loose_mid_side_stereo);
}
#undef SET_OPTION
}
encoder->bits_per_sample = (format->info.size > 4 ? 4 : format->info.size) << 3;
st_report("FLAC encoding at %i bits per sample", encoder->bits_per_sample);
FLAC__stream_encoder_set_channels(encoder->flac, format->info.channels);
FLAC__stream_encoder_set_bits_per_sample(encoder->flac, encoder->bits_per_sample);
FLAC__stream_encoder_set_sample_rate(encoder->flac, format->info.rate);
{ /* Check if rate is streamable: */
static const unsigned streamable_rates[] =
{8000, 16000, 22050, 24000, 32000, 44100, 48000, 96000};
int i;
bool streamable = false;
for (i = 0; !streamable && i < array_length(streamable_rates); ++i)
{
streamable = (streamable_rates[i] == format->info.rate);
}
if (!streamable)
{
st_report("FLAC: non-standard rate; output may not be streamable");
FLAC__stream_encoder_set_streamable_subset(encoder->flac, false);
}
}
if (format->length != 0)
{
FLAC__stream_encoder_set_total_samples_estimate(encoder->flac, format->length);
}
if (format->comment != NULL && * format->comment != '\0')
{
FLAC__StreamMetadata * metadata[1];
FLAC__StreamMetadata_VorbisComment_Entry entry;
char * comments, * comment, * end_of_comment;
/* FIXME This is never deleted; does it matter? */
metadata[0] = FLAC__metadata_object_new(FLAC__METADATA_TYPE_VORBIS_COMMENT);
/* Check if there is a FIELD=value pair already in the comment; if not, add one */
if (strchr(format->comment, '=') == NULL)
{
static const char prepend[] = "COMMENT=";
comments = malloc(strlen(format->comment) + sizeof(prepend));
if (comments != NULL)
{
strcpy(comments, prepend);
strcat(comments, format->comment);
}
}
else
{
comments = strdup(format->comment);
}
if (comments == NULL)
{
st_fail_errno(format, ST_ENOMEM, "FLAC ERROR initialising encoder");
return ST_EOF;
}
comment = comments;
do
{
entry.entry = (FLAC__byte *) comment;
end_of_comment = strchr(comment, '\n');
if (end_of_comment != NULL)
{
*end_of_comment = '\0';
comment = end_of_comment + 1;
}
entry.length = strlen((char const *) entry.entry);
FLAC__metadata_object_vorbiscomment_append_comment(metadata[0], entry, /*copy= */ true);
} while (end_of_comment != NULL);
FLAC__stream_encoder_set_metadata(encoder->flac, metadata, 1);
free(comments);
}
FLAC__stream_encoder_set_write_callback(encoder->flac, flac_stream_encoder_write_callback);
FLAC__stream_encoder_set_metadata_callback(encoder->flac, flac_stream_encoder_metadata_callback);
FLAC__stream_encoder_set_client_data(encoder->flac, format);
status = FLAC__stream_encoder_init(encoder->flac);
if (status != FLAC__STREAM_ENCODER_OK)
{
st_fail_errno(format, ST_EINVAL, "%s", FLAC__StreamEncoderStateString[status]);
return ST_EOF;
}
return ST_SUCCESS;
}
static st_ssize_t st_format_write(ft_t const format, st_sample_t const * const sampleBuffer, st_size_t const len)
{
Encoder * encoder = (Encoder *) format->priv;
unsigned i;
for (i = 0; i < len; ++i)
{
switch (encoder->bits_per_sample)
{
case 8: encoder->decoded_samples[i] = ST_SAMPLE_TO_SIGNED_BYTE(sampleBuffer[i], format->clippedCount); break;
case 16: encoder->decoded_samples[i] = ST_SAMPLE_TO_SIGNED_WORD(sampleBuffer[i], format->clippedCount); break;
case 24: encoder->decoded_samples[i] = ST_SAMPLE_TO_SIGNED_24BIT(sampleBuffer[i],format->clippedCount); break;
case 32: encoder->decoded_samples[i] = ST_SAMPLE_TO_SIGNED_DWORD(sampleBuffer[i]); break;
}
}
FLAC__stream_encoder_process_interleaved(encoder->flac, encoder->decoded_samples, len / format->info.channels);
return FLAC__stream_encoder_get_state(encoder->flac) == FLAC__STREAM_ENCODER_OK ? len : -1;
}
static int st_format_stop_write(ft_t const format)
{
Encoder * encoder = (Encoder *) format->priv;
FLAC__StreamEncoderState state = FLAC__stream_encoder_get_state(encoder->flac);
FLAC__stream_encoder_finish(encoder->flac);
FLAC__stream_encoder_delete(encoder->flac);
free(encoder->decoded_samples);
if (state != FLAC__STREAM_ENCODER_OK)
{
st_fail_errno(format, ST_EINVAL, "FLAC ERROR: failed to encode to end of stream");
return ST_EOF;
}
return ST_SUCCESS;
}
static char const * const st_format_names[] =
{
"flac",
NULL
};
static st_format_t const st_format =
{
st_format_names,
NULL,
ST_FILE_STEREO,
st_format_start_read,
st_format_read,
st_format_stop_read,
st_format_start_write,
st_format_write,
st_format_stop_write,
st_format_nothing_seek
};
st_format_t const * st_flac_format_fn(void)
{
return &st_format;
}
#endif /* HAVE_LIBFLAC */