static PyObject*
FlacDecoder_offsets(decoders_FlacDecoder* self, PyObject *args)
{
int channel;
struct flac_frame_header frame_header;
flac_status error;
PyObject* offsets = PyList_New(0);
PyObject* offset_pair;
uint32_t samples;
long offset;
PyThreadState *thread_state = PyEval_SaveThread();
while (self->remaining_samples > 0) {
self->subframe_data->reset(self->subframe_data);
offset = br_ftell(self->bitstream);
if (!setjmp(*br_try(self->bitstream))) {
/*read frame header*/
if ((error = flacdec_read_frame_header(self->bitstream,
&(self->streaminfo),
&frame_header)) != OK) {
PyEval_RestoreThread(thread_state);
PyErr_SetString(PyExc_ValueError, FlacDecoder_strerror(error));
goto error;
}
samples = frame_header.block_size;
/*read 1 subframe per channel*/
for (channel = 0; channel < frame_header.channel_count; channel++)
if ((error =
flacdec_read_subframe(
self->bitstream,
self->qlp_coeffs,
self->residuals,
(unsigned int)MIN(frame_header.block_size,
self->remaining_samples),
flacdec_subframe_bits_per_sample(&frame_header,
channel),
self->subframe_data->append(self->subframe_data))) !=
OK) {
PyEval_RestoreThread(thread_state);
PyErr_SetString(PyExc_ValueError,
FlacDecoder_strerror(error));
goto error;
}
/*read CRC-16*/
self->bitstream->byte_align(self->bitstream);
self->bitstream->read(self->bitstream, 16);
/*decrement remaining samples*/
self->remaining_samples -= frame_header.block_size;
/*add offset pair to our list*/
PyEval_RestoreThread(thread_state);
offset_pair = Py_BuildValue("(i, I)", offset, samples);
PyList_Append(offsets, offset_pair);
Py_DECREF(offset_pair);
thread_state = PyEval_SaveThread();
} else {
/*handle I/O error during read*/
PyEval_RestoreThread(thread_state);
PyErr_SetString(PyExc_IOError, "EOF reading frame");
goto error;
}
br_etry(self->bitstream);
}
self->stream_finalized = 1;
PyEval_RestoreThread(thread_state);
return offsets;
error:
Py_XDECREF(offsets);
br_etry(self->bitstream);
return NULL;
}
int main(int argc, char* argv[]) {
FILE* ogg_file;
OggReader* ogg_stream = NULL;
BitstreamReader* packet = NULL;
struct flac_STREAMINFO streaminfo;
uint16_t header_packets;
a_int* residuals = NULL;
a_int* qlp_coeffs = NULL;
aa_int* subframe_data = NULL;
a_int* framelist_data = NULL;
ogg_status result;
uint16_t crc16 = 0;
FrameList_int_to_char_converter converter;
unsigned pcm_size;
unsigned output_data_size = 1;
uint8_t* output_data = NULL;
audiotools__MD5Context md5;
unsigned char stream_md5sum[16];
const static unsigned char blank_md5sum[16] = {0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0};
if (argc < 2) {
fprintf(stderr, "*** Usage: %s <file.oga>\n", argv[0]);
return 1;
}
/*open input file for reading*/
if ((ogg_file = fopen(argv[1], "rb")) == NULL) {
fprintf(stderr, "*** %s: %s\n", argv[1], strerror(errno));
return 1;
} else {
/*open bitstream and setup temporary arrays/buffers*/
ogg_stream = oggreader_open(ogg_file);
packet = br_substream_new(BS_BIG_ENDIAN);
subframe_data = aa_int_new();
residuals = a_int_new();
qlp_coeffs = a_int_new();
framelist_data = a_int_new();
output_data = malloc(output_data_size);
}
/*the first packet should be the FLAC's STREAMINFO*/
if ((result = oggreader_next_packet(ogg_stream, packet)) == OGG_OK) {
if (!oggflac_read_streaminfo(packet, &streaminfo, &header_packets)) {
goto error;
} else {
converter = FrameList_get_int_to_char_converter(
streaminfo.bits_per_sample, 0, 1);
}
} else {
fprintf(stderr, "*** Error: %s\n", ogg_strerror(result));
goto error;
}
/*skip subsequent header packets*/
for (; header_packets > 0; header_packets--) {
if ((result = oggreader_next_packet(ogg_stream, packet)) != OGG_OK) {
fprintf(stderr, "*** Error: %s\n", ogg_strerror(result));
goto error;
}
}
/*initialize the output MD5 sum*/
audiotools__MD5Init(&md5);
/*add callback for CRC16 calculation*/
br_add_callback(packet, (bs_callback_f)flac_crc16, &crc16);
/*decode the next FrameList from the stream*/
result = oggreader_next_packet(ogg_stream, packet);
while (result != OGG_STREAM_FINISHED) {
if (result == OGG_OK) {
flac_status flac_status;
struct flac_frame_header frame_header;
unsigned channel;
subframe_data->reset(subframe_data);
if (!setjmp(*br_try(packet))) {
/*read frame header*/
if ((flac_status =
flacdec_read_frame_header(packet,
&streaminfo,
&frame_header)) != OK) {
fprintf(stderr, "*** Error: %s\n",
FlacDecoder_strerror(flac_status));
br_etry(packet);
goto error;
}
/*read 1 subframe per channel*/
for (channel = 0;
channel < frame_header.channel_count;
channel++)
if ((flac_status = flacdec_read_subframe(
packet,
qlp_coeffs,
residuals,
frame_header.block_size,
flacdec_subframe_bits_per_sample(&frame_header,
channel),
subframe_data->append(subframe_data))) != OK) {
fprintf(stderr, "*** Error: %s\n",
FlacDecoder_strerror(flac_status));
br_etry(packet);
goto error;
}
br_etry(packet);
} else {
br_etry(packet);
fprintf(stderr, "*** I/O Error reading FLAC frame\n");
goto error;
}
/*handle difference channels, if any*/
flacdec_decorrelate_channels(frame_header.channel_assignment,
subframe_data,
framelist_data);
/*check CRC-16*/
packet->byte_align(packet);
packet->read(packet, 16);
if (crc16 != 0) {
fprintf(stderr, "*** Error: invalid checksum in frame\n");
goto error;
}
/*turn FrameList into string of output*/
pcm_size = (streaminfo.bits_per_sample / 8) * framelist_data->len;
if (pcm_size > output_data_size) {
output_data_size = pcm_size;
output_data = realloc(output_data, output_data_size);
}
FrameList_samples_to_char(output_data,
framelist_data->_,
converter,
framelist_data->len,
streaminfo.bits_per_sample);
/*update MD5 sum*/
audiotools__MD5Update(&md5, output_data, pcm_size);
/*output string to stdout*/
fwrite(output_data, sizeof(unsigned char), pcm_size, stdout);
result = oggreader_next_packet(ogg_stream, packet);
} else {
/*some error reading Ogg stream*/
fprintf(stderr, "*** Error: %s\n", ogg_strerror(result));
goto error;
}
}
/*Ogg stream is finished so verify stream's MD5 sum*/
audiotools__MD5Final(stream_md5sum, &md5);
if (!((memcmp(streaminfo.md5sum, blank_md5sum, 16) == 0) ||
(memcmp(stream_md5sum, streaminfo.md5sum, 16) == 0))) {
fprintf(stderr, "*** MD5 mismatch at end of stream\n");
goto error;
}
/*close streams, temporary buffers*/
oggreader_close(ogg_stream);
packet->close(packet);
subframe_data->del(subframe_data);
residuals->del(residuals);
qlp_coeffs->del(qlp_coeffs);
framelist_data->del(framelist_data);
free(output_data);
return 0;
error:
oggreader_close(ogg_stream);
packet->close(packet);
subframe_data->del(subframe_data);
residuals->del(residuals);
qlp_coeffs->del(qlp_coeffs);
framelist_data->del(framelist_data);
free(output_data);
return 1;
}
PyObject*
FlacDecoder_read(decoders_FlacDecoder* self, PyObject *args)
{
uint16_t crc16 = 0;
int channel;
struct flac_frame_header frame_header;
PyObject* framelist;
PyThreadState *thread_state;
flac_status error;
if (self->closed) {
PyErr_SetString(PyExc_ValueError, "cannot read closed stream");
return NULL;
}
self->subframe_data->reset(self->subframe_data);
/*if all samples have been read, return an empty FrameList*/
if (self->stream_finalized) {
return empty_FrameList(self->audiotools_pcm,
self->streaminfo.channels,
self->streaminfo.bits_per_sample);
}
if (self->remaining_samples < 1) {
self->stream_finalized = 1;
if (FlacDecoder_verify_okay(self)) {
return empty_FrameList(self->audiotools_pcm,
self->streaminfo.channels,
self->streaminfo.bits_per_sample);
} else {
PyErr_SetString(PyExc_ValueError,
"MD5 mismatch at end of stream");
return NULL;
}
}
thread_state = PyEval_SaveThread();
if (!setjmp(*br_try(self->bitstream))) {
/*add callback for CRC16 calculation*/
br_add_callback(self->bitstream, (bs_callback_f)flac_crc16, &crc16);
/*read frame header*/
if ((error = flacdec_read_frame_header(self->bitstream,
&(self->streaminfo),
&frame_header)) != OK) {
br_pop_callback(self->bitstream, NULL);
PyEval_RestoreThread(thread_state);
PyErr_SetString(PyExc_ValueError, FlacDecoder_strerror(error));
br_etry(self->bitstream);
return NULL;
}
/*read 1 subframe per channel*/
for (channel = 0; channel < frame_header.channel_count; channel++)
if ((error =
flacdec_read_subframe(
self->bitstream,
self->qlp_coeffs,
self->residuals,
(unsigned int)MIN(frame_header.block_size,
self->remaining_samples),
flacdec_subframe_bits_per_sample(&frame_header,
channel),
self->subframe_data->append(self->subframe_data))) != OK) {
br_pop_callback(self->bitstream, NULL);
PyEval_RestoreThread(thread_state);
PyErr_SetString(PyExc_ValueError, FlacDecoder_strerror(error));
br_etry(self->bitstream);
return NULL;
}
/*handle difference channels, if any*/
flacdec_decorrelate_channels(frame_header.channel_assignment,
self->subframe_data,
self->framelist_data);
/*check CRC-16*/
self->bitstream->byte_align(self->bitstream);
self->bitstream->read(self->bitstream, 16);
br_pop_callback(self->bitstream, NULL);
if (crc16 != 0) {
PyEval_RestoreThread(thread_state);
PyErr_SetString(PyExc_ValueError, "invalid checksum in frame");
br_etry(self->bitstream);
return NULL;
}
/*decrement remaining samples*/
self->remaining_samples -= frame_header.block_size;
} else {
/*handle I/O error during read*/
br_pop_callback(self->bitstream, NULL);
PyEval_RestoreThread(thread_state);
PyErr_SetString(PyExc_IOError, "EOF reading frame");
br_etry(self->bitstream);
return NULL;
}
br_etry(self->bitstream);
PyEval_RestoreThread(thread_state);
framelist = array_i_to_FrameList(self->audiotools_pcm,
self->framelist_data,
frame_header.channel_count,
frame_header.bits_per_sample);
if (framelist != NULL) {
/*update MD5 sum*/
if (FlacDecoder_update_md5sum(self, framelist) == OK)
/*return pcm.FrameList Python object*/
return framelist;
else {
Py_DECREF(framelist);
return NULL;
}
} else {
return NULL;
}
}
static PyObject*
OggFlacDecoder_read(decoders_OggFlacDecoder *self, PyObject *args) {
ogg_status ogg_status;
flac_status flac_status;
struct flac_frame_header frame_header;
int channel;
PyObject *framelist;
PyThreadState *thread_state;
if (self->closed) {
PyErr_SetString(PyExc_ValueError, "cannot read closed stream");
return NULL;
}
self->subframe_data->reset(self->subframe_data);
/*if all samples have been read, return an empty FrameList*/
if (self->stream_finalized) {
return empty_FrameList(self->audiotools_pcm,
self->streaminfo.channels,
self->streaminfo.bits_per_sample);
}
thread_state = PyEval_SaveThread();
ogg_status = oggreader_next_packet(self->ogg_stream, self->packet);
PyEval_RestoreThread(thread_state);
if (ogg_status == OGG_OK) {
/*decode the next FrameList from the stream*/
thread_state = PyEval_SaveThread();
self->crc16 = 0;
if (!setjmp(*br_try(self->packet))) {
/*read frame header*/
if ((flac_status =
flacdec_read_frame_header(self->packet,
&(self->streaminfo),
&frame_header)) != OK) {
PyEval_RestoreThread(thread_state);
PyErr_SetString(PyExc_ValueError,
FlacDecoder_strerror(flac_status));
br_etry(self->packet);
return NULL;
}
/*read 1 subframe per channel*/
for (channel = 0; channel < frame_header.channel_count; channel++)
if ((flac_status = flacdec_read_subframe(
self->packet,
self->qlp_coeffs,
self->residuals,
frame_header.block_size,
flacdec_subframe_bits_per_sample(&frame_header,
channel),
self->subframe_data->append(self->subframe_data))) !=
OK) {
PyEval_RestoreThread(thread_state);
PyErr_SetString(PyExc_ValueError,
FlacDecoder_strerror(flac_status));
br_etry(self->packet);
return NULL;
}
br_etry(self->packet);
/*handle difference channels, if any*/
flacdec_decorrelate_channels(frame_header.channel_assignment,
self->subframe_data,
self->framelist_data);
/*check CRC-16*/
self->packet->byte_align(self->packet);
self->packet->read(self->packet, 16);
if (self->crc16 != 0) {
PyEval_RestoreThread(thread_state);
PyErr_SetString(PyExc_ValueError, "invalid checksum in frame");
return NULL;
}
PyEval_RestoreThread(thread_state);
framelist = a_int_to_FrameList(self->audiotools_pcm,
self->framelist_data,
frame_header.channel_count,
frame_header.bits_per_sample);
if (framelist != NULL) {
/*update MD5 sum*/
if (OggFlacDecoder_update_md5sum(self, framelist) == 1)
/*return pcm.FrameList Python object*/
return framelist;
else {
Py_DECREF(framelist);
return NULL;
}
} else {
return NULL;
}
} else {
/*read error decoding FLAC frame*/
PyEval_RestoreThread(thread_state);
PyErr_SetString(PyExc_IOError, "I/O error decoding FLAC frame");
br_etry(self->packet);
return NULL;
}
} else if (ogg_status == OGG_STREAM_FINISHED) {
/*Ogg stream is finished so verify stream's MD5 sum
then return an empty FrameList if it matches correctly*/
if (OggFlacDecoder_verify_okay(self)) {
self->stream_finalized = 1;
return empty_FrameList(self->audiotools_pcm,
self->streaminfo.channels,
self->streaminfo.bits_per_sample);
} else {
PyErr_SetString(PyExc_ValueError,
"MD5 mismatch at end of stream");
return NULL;
}
} else {
/*error reading the next Ogg packet,
so raise the appropriate exception*/
PyErr_SetString(ogg_exception(ogg_status), ogg_strerror(ogg_status));
return NULL;
}
}
