| 1 | /* license:BSD-3-Clause |
| 2 | * copyright-holders:Aaron Giles |
| 3 | *************************************************************************** |
| 4 | |
| 5 | flac.c |
| 6 | |
| 7 | FLAC compression wrappers |
| 8 | |
| 9 | ***************************************************************************/ |
| 10 | |
| 11 | #include <assert.h> |
| 12 | #include <string.h> |
| 13 | #include "flac.h" |
| 14 | |
| 15 | /*************************************************************************** |
| 16 | * FLAC DECODER |
| 17 | *************************************************************************** |
| 18 | */ |
| 19 | |
| 20 | static FLAC__StreamDecoderReadStatus flac_decoder_read_callback_static(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes, void *client_data); |
| 21 | FLAC__StreamDecoderReadStatus flac_decoder_read_callback(void* client_data, FLAC__byte buffer[], size_t *bytes); |
| 22 | static void flac_decoder_metadata_callback_static(const FLAC__StreamDecoder *decoder, const FLAC__StreamMetadata *metadata, void *client_data); |
| 23 | static FLAC__StreamDecoderTellStatus flac_decoder_tell_callback_static(const FLAC__StreamDecoder *decoder, FLAC__uint64 *absolute_byte_offset, void *client_data); |
| 24 | static FLAC__StreamDecoderWriteStatus flac_decoder_write_callback_static(const FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[], void *client_data); |
| 25 | FLAC__StreamDecoderWriteStatus flac_decoder_write_callback(void* client_data, const FLAC__Frame *frame, const FLAC__int32 * const buffer[]); |
| 26 | static void flac_decoder_error_callback_static(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status, void *client_data); |
| 27 | |
| 28 | /* getters (valid after reset) */ |
| 29 | static uint32_t sample_rate(flac_decoder *decoder) { return decoder->sample_rate; } |
| 30 | static uint8_t channels(flac_decoder *decoder) { return decoder->channels; } |
| 31 | static uint8_t bits_per_sample(flac_decoder *decoder) { return decoder->bits_per_sample; } |
| 32 | static uint32_t total_samples(flac_decoder *decoder) { return FLAC__stream_decoder_get_total_samples(decoder->decoder); } |
| 33 | static FLAC__StreamDecoderState state(flac_decoder *decoder) { return FLAC__stream_decoder_get_state(decoder->decoder); } |
| 34 | static const char *state_string(flac_decoder *decoder) { return FLAC__stream_decoder_get_resolved_state_string(decoder->decoder); } |
| 35 | |
| 36 | /*------------------------------------------------- |
| 37 | * flac_decoder - constructor |
| 38 | *------------------------------------------------- |
| 39 | */ |
| 40 | |
| 41 | void flac_decoder_init(flac_decoder *decoder) |
| 42 | { |
| 43 | decoder->decoder = FLAC__stream_decoder_new(); |
| 44 | decoder->sample_rate = 0; |
| 45 | decoder->channels = 0; |
| 46 | decoder->bits_per_sample = 0; |
| 47 | decoder->compressed_offset = 0; |
| 48 | decoder->compressed_start = NULL; |
| 49 | decoder->compressed_length = 0; |
| 50 | decoder->compressed2_start = NULL; |
| 51 | decoder->compressed2_length = 0; |
| 52 | decoder->uncompressed_offset = 0; |
| 53 | decoder->uncompressed_length = 0; |
| 54 | decoder->uncompressed_swap = 0; |
| 55 | } |
| 56 | |
| 57 | /*------------------------------------------------- |
| 58 | * flac_decoder - destructor |
| 59 | *------------------------------------------------- |
| 60 | */ |
| 61 | |
| 62 | void flac_decoder_free(flac_decoder* decoder) |
| 63 | { |
| 64 | if ((decoder != NULL) && (decoder->decoder != NULL)) |
| 65 | FLAC__stream_decoder_delete(decoder->decoder); |
| 66 | } |
| 67 | |
| 68 | /*------------------------------------------------- |
| 69 | * reset - reset state with the original |
| 70 | * parameters |
| 71 | *------------------------------------------------- |
| 72 | */ |
| 73 | |
| 74 | static int flac_decoder_internal_reset(flac_decoder* decoder) |
| 75 | { |
| 76 | decoder->compressed_offset = 0; |
| 77 | if (FLAC__stream_decoder_init_stream(decoder->decoder, |
| 78 | &flac_decoder_read_callback_static, |
| 79 | NULL, |
| 80 | &flac_decoder_tell_callback_static, |
| 81 | NULL, |
| 82 | NULL, |
| 83 | &flac_decoder_write_callback_static, |
| 84 | &flac_decoder_metadata_callback_static, |
| 85 | &flac_decoder_error_callback_static, decoder) != FLAC__STREAM_DECODER_INIT_STATUS_OK) |
| 86 | return 0; |
| 87 | return FLAC__stream_decoder_process_until_end_of_metadata(decoder->decoder); |
| 88 | } |
| 89 | |
| 90 | /*------------------------------------------------- |
| 91 | * reset - reset state with new memory parameters |
| 92 | * and a custom-generated header |
| 93 | *------------------------------------------------- |
| 94 | */ |
| 95 | |
| 96 | int flac_decoder_reset(flac_decoder* decoder, uint32_t sample_rate, uint8_t num_channels, uint32_t block_size, const void *buffer, uint32_t length) |
| 97 | { |
| 98 | /* modify the template header with our parameters */ |
| 99 | static const uint8_t s_header_template[0x2a] = |
| 100 | { |
| 101 | 0x66, 0x4C, 0x61, 0x43, /* +00: 'fLaC' stream header */ |
| 102 | 0x80, /* +04: metadata block type 0 (STREAMINFO), */ |
| 103 | /* flagged as last block */ |
| 104 | 0x00, 0x00, 0x22, /* +05: metadata block length = 0x22 */ |
| 105 | 0x00, 0x00, /* +08: minimum block size */ |
| 106 | 0x00, 0x00, /* +0A: maximum block size */ |
| 107 | 0x00, 0x00, 0x00, /* +0C: minimum frame size (0 == unknown) */ |
| 108 | 0x00, 0x00, 0x00, /* +0F: maximum frame size (0 == unknown) */ |
| 109 | 0x0A, 0xC4, 0x42, 0xF0, 0x00, 0x00, 0x00, 0x00, /* +12: sample rate (0x0ac44 == 44100), */ |
| 110 | /* numchannels (2), sample bits (16), */ |
| 111 | /* samples in stream (0 == unknown) */ |
| 112 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* +1A: MD5 signature (0 == none) */ |
| 113 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 /* +2A: start of stream data */ |
| 114 | }; |
| 115 | memcpy(decoder->custom_header, s_header_template, sizeof(s_header_template)); |
| 116 | decoder->custom_header[0x08] = decoder->custom_header[0x0a] = block_size >> 8; |
| 117 | decoder->custom_header[0x09] = decoder->custom_header[0x0b] = block_size & 0xff; |
| 118 | decoder->custom_header[0x12] = sample_rate >> 12; |
| 119 | decoder->custom_header[0x13] = sample_rate >> 4; |
| 120 | decoder->custom_header[0x14] = (sample_rate << 4) | ((num_channels - 1) << 1); |
| 121 | |
| 122 | /* configure the header ahead of the provided buffer */ |
| 123 | decoder->compressed_start = (const FLAC__byte *)(decoder->custom_header); |
| 124 | decoder->compressed_length = sizeof(decoder->custom_header); |
| 125 | decoder->compressed2_start = (const FLAC__byte *)(buffer); |
| 126 | decoder->compressed2_length = length; |
| 127 | return flac_decoder_internal_reset(decoder); |
| 128 | } |
| 129 | |
| 130 | /*------------------------------------------------- |
| 131 | * decode_interleaved - decode to an interleaved |
| 132 | * sound stream |
| 133 | *------------------------------------------------- |
| 134 | */ |
| 135 | |
| 136 | int flac_decoder_decode_interleaved(flac_decoder* decoder, int16_t *samples, uint32_t num_samples, int swap_endian) |
| 137 | { |
| 138 | /* configure the uncompressed buffer */ |
| 139 | memset(decoder->uncompressed_start, 0, sizeof(decoder->uncompressed_start)); |
| 140 | decoder->uncompressed_start[0] = samples; |
| 141 | decoder->uncompressed_offset = 0; |
| 142 | decoder->uncompressed_length = num_samples; |
| 143 | decoder->uncompressed_swap = swap_endian; |
| 144 | |
| 145 | /* loop until we get everything we want */ |
| 146 | while (decoder->uncompressed_offset < decoder->uncompressed_length) |
| 147 | if (!FLAC__stream_decoder_process_single(decoder->decoder)) |
| 148 | return 0; |
| 149 | return 1; |
| 150 | } |
| 151 | |
| 152 | #if 0 |
| 153 | /*------------------------------------------------- |
| 154 | * decode - decode to an multiple independent |
| 155 | * data streams |
| 156 | *------------------------------------------------- |
| 157 | */ |
| 158 | |
| 159 | bool flac_decoder::decode(int16_t **samples, uint32_t num_samples, bool swap_endian) |
| 160 | { |
| 161 | /* make sure we don't have too many channels */ |
| 162 | int chans = channels(); |
| 163 | if (chans > ARRAY_LENGTH(m_uncompressed_start)) |
| 164 | return false; |
| 165 | |
| 166 | /* configure the uncompressed buffer */ |
| 167 | memset(m_uncompressed_start, 0, sizeof(m_uncompressed_start)); |
| 168 | for (int curchan = 0; curchan < chans; curchan++) |
| 169 | m_uncompressed_start[curchan] = samples[curchan]; |
| 170 | m_uncompressed_offset = 0; |
| 171 | m_uncompressed_length = num_samples; |
| 172 | m_uncompressed_swap = swap_endian; |
| 173 | |
| 174 | /* loop until we get everything we want */ |
| 175 | while (m_uncompressed_offset < m_uncompressed_length) |
| 176 | if (!FLAC__stream_decoder_process_single(m_decoder)) |
| 177 | return false; |
| 178 | return true; |
| 179 | } |
| 180 | #endif |
| 181 | |
| 182 | /*------------------------------------------------- |
| 183 | * finish - finish up the decode |
| 184 | *------------------------------------------------- |
| 185 | */ |
| 186 | |
| 187 | uint32_t flac_decoder_finish(flac_decoder* decoder) |
| 188 | { |
| 189 | /* get the final decoding position and move forward */ |
| 190 | FLAC__uint64 position = 0; |
| 191 | FLAC__stream_decoder_get_decode_position(decoder->decoder, &position); |
| 192 | FLAC__stream_decoder_finish(decoder->decoder); |
| 193 | |
| 194 | /* adjust position if we provided the header */ |
| 195 | if (position == 0) |
| 196 | return 0; |
| 197 | if (decoder->compressed_start == (const FLAC__byte *)(decoder->custom_header)) |
| 198 | position -= decoder->compressed_length; |
| 199 | return position; |
| 200 | } |
| 201 | |
| 202 | /*------------------------------------------------- |
| 203 | * read_callback - handle reads from the input |
| 204 | * stream |
| 205 | *------------------------------------------------- |
| 206 | */ |
| 207 | |
| 208 | #define MIN(x, y) ((x) < (y) ? (x) : (y)) |
| 209 | |
| 210 | FLAC__StreamDecoderReadStatus flac_decoder_read_callback_static(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes, void *client_data) |
| 211 | { |
| 212 | return flac_decoder_read_callback(client_data, buffer, bytes); |
| 213 | } |
| 214 | |
| 215 | FLAC__StreamDecoderReadStatus flac_decoder_read_callback(void* client_data, FLAC__byte buffer[], size_t *bytes) |
| 216 | { |
| 217 | flac_decoder* decoder = (flac_decoder*)client_data; |
| 218 | |
| 219 | uint32_t expected = *bytes; |
| 220 | |
| 221 | /* copy from primary buffer first */ |
| 222 | uint32_t outputpos = 0; |
| 223 | if (outputpos < *bytes && decoder->compressed_offset < decoder->compressed_length) |
| 224 | { |
| 225 | uint32_t bytes_to_copy = MIN(*bytes - outputpos, decoder->compressed_length - decoder->compressed_offset); |
| 226 | memcpy(&buffer[outputpos], decoder->compressed_start + decoder->compressed_offset, bytes_to_copy); |
| 227 | outputpos += bytes_to_copy; |
| 228 | decoder->compressed_offset += bytes_to_copy; |
| 229 | } |
| 230 | |
| 231 | /* once we're out of that, copy from the secondary buffer */ |
| 232 | if (outputpos < *bytes && decoder->compressed_offset < decoder->compressed_length + decoder->compressed2_length) |
| 233 | { |
| 234 | uint32_t bytes_to_copy = MIN(*bytes - outputpos, decoder->compressed2_length - (decoder->compressed_offset - decoder->compressed_length)); |
| 235 | memcpy(&buffer[outputpos], decoder->compressed2_start + decoder->compressed_offset - decoder->compressed_length, bytes_to_copy); |
| 236 | outputpos += bytes_to_copy; |
| 237 | decoder->compressed_offset += bytes_to_copy; |
| 238 | } |
| 239 | *bytes = outputpos; |
| 240 | |
| 241 | /* return based on whether we ran out of data */ |
| 242 | return (*bytes < expected) ? FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM : FLAC__STREAM_DECODER_READ_STATUS_CONTINUE; |
| 243 | } |
| 244 | |
| 245 | /*------------------------------------------------- |
| 246 | * metadata_callback - handle STREAMINFO metadata |
| 247 | *------------------------------------------------- |
| 248 | */ |
| 249 | |
| 250 | void flac_decoder_metadata_callback_static(const FLAC__StreamDecoder *decoder, const FLAC__StreamMetadata *metadata, void *client_data) |
| 251 | { |
| 252 | flac_decoder *fldecoder; |
| 253 | /* ignore all but STREAMINFO metadata */ |
| 254 | if (metadata->type != FLAC__METADATA_TYPE_STREAMINFO) |
| 255 | return; |
| 256 | |
| 257 | /* parse out the data we care about */ |
| 258 | fldecoder = (flac_decoder *)(client_data); |
| 259 | fldecoder->sample_rate = metadata->data.stream_info.sample_rate; |
| 260 | fldecoder->bits_per_sample = metadata->data.stream_info.bits_per_sample; |
| 261 | fldecoder->channels = metadata->data.stream_info.channels; |
| 262 | } |
| 263 | |
| 264 | /*------------------------------------------------- |
| 265 | * tell_callback - handle requests to find out |
| 266 | * where in the input stream we are |
| 267 | *------------------------------------------------- |
| 268 | */ |
| 269 | |
| 270 | FLAC__StreamDecoderTellStatus flac_decoder_tell_callback_static(const FLAC__StreamDecoder *decoder, FLAC__uint64 *absolute_byte_offset, void *client_data) |
| 271 | { |
| 272 | *absolute_byte_offset = ((flac_decoder *)client_data)->compressed_offset; |
| 273 | return FLAC__STREAM_DECODER_TELL_STATUS_OK; |
| 274 | } |
| 275 | |
| 276 | /*------------------------------------------------- |
| 277 | * write_callback - handle writes to the output |
| 278 | * stream |
| 279 | *------------------------------------------------- |
| 280 | */ |
| 281 | |
| 282 | FLAC__StreamDecoderWriteStatus flac_decoder_write_callback_static(const FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[], void *client_data) |
| 283 | { |
| 284 | return flac_decoder_write_callback(client_data, frame, buffer); |
| 285 | } |
| 286 | |
| 287 | FLAC__StreamDecoderWriteStatus flac_decoder_write_callback(void *client_data, const FLAC__Frame *frame, const FLAC__int32 * const buffer[]) |
| 288 | { |
| 289 | int sampnum, chan; |
| 290 | int shift, blocksize; |
| 291 | flac_decoder * decoder = (flac_decoder *)client_data; |
| 292 | |
| 293 | assert(frame->header.channels == channels(decoder)); |
| 294 | |
| 295 | /* interleaved case */ |
| 296 | shift = decoder->uncompressed_swap ? 8 : 0; |
| 297 | blocksize = frame->header.blocksize; |
| 298 | if (decoder->uncompressed_start[1] == NULL) |
| 299 | { |
| 300 | int16_t *dest = decoder->uncompressed_start[0] + decoder->uncompressed_offset * frame->header.channels; |
| 301 | for (sampnum = 0; sampnum < blocksize && decoder->uncompressed_offset < decoder->uncompressed_length; sampnum++, decoder->uncompressed_offset++) |
| 302 | for (chan = 0; chan < frame->header.channels; chan++) |
| 303 | *dest++ = (int16_t)((((uint16_t)buffer[chan][sampnum]) << shift) | (((uint16_t)buffer[chan][sampnum]) >> shift)); |
| 304 | } |
| 305 | |
| 306 | /* non-interleaved case */ |
| 307 | else |
| 308 | { |
| 309 | for (sampnum = 0; sampnum < blocksize && decoder->uncompressed_offset < decoder->uncompressed_length; sampnum++, decoder->uncompressed_offset++) |
| 310 | for (chan = 0; chan < frame->header.channels; chan++) |
| 311 | if (decoder->uncompressed_start[chan] != NULL) |
| 312 | decoder->uncompressed_start[chan][decoder->uncompressed_offset] = (int16_t) ( (((uint16_t)(buffer[chan][sampnum])) << shift) | ( ((uint16_t)(buffer[chan][sampnum])) >> shift) ); |
| 313 | } |
| 314 | return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE; |
| 315 | } |
| 316 | |
| 317 | /** |
| 318 | * @fn void flac_decoder::error_callback_static(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status, void *client_data) |
| 319 | * |
| 320 | * @brief ------------------------------------------------- |
| 321 | * error_callback - handle errors (ignore them) |
| 322 | * -------------------------------------------------. |
| 323 | * |
| 324 | * @param decoder The decoder. |
| 325 | * @param status The status. |
| 326 | * @param [in,out] client_data If non-null, information describing the client. |
| 327 | */ |
| 328 | |
| 329 | void flac_decoder_error_callback_static(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status, void *client_data) |
| 330 | { |
| 331 | } |