-/*****************************************************************************
- * SyncInfo: parse FLAC sync info
- *****************************************************************************/
-static int SyncInfo( decoder_t *p_dec, uint8_t *p_buf,
- unsigned int * pi_channels,
- unsigned int * pi_channels_conf,
- unsigned int * pi_sample_rate,
- int * pi_bits_per_sample )
-{
- decoder_sys_t *p_sys = p_dec->p_sys;
- int i_header, i_temp, i_read;
- unsigned i_blocksize = 0;
- int i_blocksize_hint = 0, i_sample_rate_hint = 0;
- uint64_t i_sample_number = 0;
-
- bool b_variable_blocksize = ( p_sys->b_stream_info &&
- p_sys->stream_info.min_blocksize != p_sys->stream_info.max_blocksize );
- bool b_fixed_blocksize = ( p_sys->b_stream_info &&
- p_sys->stream_info.min_blocksize == p_sys->stream_info.max_blocksize );
-
- /* Check syncword */
- if( p_buf[0] != 0xFF || p_buf[1] != 0xF8 ) return 0;
-
- /* Check there is no emulated sync code in the rest of the header */
- if( p_buf[2] == 0xff || p_buf[3] == 0xFF ) return 0;
-
- /* Find blocksize (framelength) */
- switch( i_temp = p_buf[2] >> 4 )
- {
- case 0:
- if( b_fixed_blocksize )
- i_blocksize = p_sys->stream_info.min_blocksize;
- else return 0; /* We can't do anything with this */
- break;
-
- case 1:
- i_blocksize = 192;
- break;
-
- case 2:
- case 3:
- case 4:
- case 5:
- i_blocksize = 576 << (i_temp - 2);
- break;
-
- case 6:
- case 7:
- i_blocksize_hint = i_temp;
- break;
-
- case 8:
- case 9:
- case 10:
- case 11:
- case 12:
- case 13:
- case 14:
- case 15:
- i_blocksize = 256 << (i_temp - 8);
- break;
- }
-
- /* Find samplerate */
- switch( i_temp = p_buf[2] & 0x0f )
- {
- case 0:
- if( p_sys->b_stream_info )
- *pi_sample_rate = p_sys->stream_info.sample_rate;
- else return 0; /* We can't do anything with this */
- break;
-
- case 1:
- case 2:
- case 3:
- return 0;
- break;
-
- case 4:
- *pi_sample_rate = 8000;
- break;
-
- case 5:
- *pi_sample_rate = 16000;
- break;
-
- case 6:
- *pi_sample_rate = 22050;
- break;
-
- case 7:
- *pi_sample_rate = 24000;
- break;
-
- case 8:
- *pi_sample_rate = 32000;
- break;
-
- case 9:
- *pi_sample_rate = 44100;
- break;
-
- case 10:
- *pi_sample_rate = 48000;
- break;
-
- case 11:
- *pi_sample_rate = 96000;
- break;
-
- case 12:
- case 13:
- case 14:
- i_sample_rate_hint = i_temp;
- break;
-
- case 15:
- return 0;
- }
-
- /* Find channels */
- i_temp = (unsigned)(p_buf[3] >> 4);
- if( i_temp & 8 )
- {
-#ifdef USE_LIBFLAC
- int i_channel_assignment; /* ??? */
-
- switch( i_temp & 7 )
- {
- case 0:
- i_channel_assignment = FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE;
- break;
- case 1:
- i_channel_assignment = FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE;
- break;
- case 2:
- i_channel_assignment = FLAC__CHANNEL_ASSIGNMENT_MID_SIDE;
- break;
- default:
- return 0;
- break;
- }
-#endif
-
- *pi_channels = 2;
- }
- else
- {
- *pi_channels = i_temp + 1;
- *pi_channels_conf = pi_channels_maps[ *pi_channels ];
- }
-
- /* Find bits per sample */
- switch( i_temp = (unsigned)(p_buf[3] & 0x0e) >> 1 )
- {
- case 0:
- if( p_sys->b_stream_info )
- *pi_bits_per_sample = p_sys->stream_info.bits_per_sample;
- else
- return 0;
- break;
-
- case 1:
- *pi_bits_per_sample = 8;
- break;
-
- case 2:
- *pi_bits_per_sample = 12;
- break;
-
- case 4:
- *pi_bits_per_sample = 16;
- break;
-
- case 5:
- *pi_bits_per_sample = 20;
- break;
-
- case 6:
- *pi_bits_per_sample = 24;
- break;
-
- case 3:
- case 7:
- return 0;
- break;
- }
-
- /* Zero padding bit */
- if( p_buf[3] & 0x01 ) return 0;
-
- /* End of fixed size header */
- i_header = 4;
-
- /* Find Sample/Frame number */
- if( i_blocksize_hint && b_variable_blocksize )
- {
- i_sample_number = read_utf8( &p_buf[i_header++], &i_read );
- if( i_sample_number == INT64_C(0xffffffffffffffff) ) return 0;
- }
- else
- {
- i_sample_number = read_utf8( &p_buf[i_header++], &i_read );
- if( i_sample_number == INT64_C(0xffffffffffffffff) ) return 0;
-
- if( p_sys->b_stream_info )
- i_sample_number *= p_sys->stream_info.min_blocksize;
- }
-
- i_header += i_read;
-
- /* Read blocksize */
- if( i_blocksize_hint )
- {
- int i_val1 = p_buf[i_header++];
- if( i_blocksize_hint == 7 )
- {
- int i_val2 = p_buf[i_header++];
- i_val1 = (i_val1 << 8) | i_val2;
- }
- i_blocksize = i_val1 + 1;
- }
-
- /* Read sample rate */
- if( i_sample_rate_hint )
- {
- int i_val1 = p_buf[i_header++];
- if( i_sample_rate_hint != 12 )
- {
- int i_val2 = p_buf[i_header++];
- i_val1 = (i_val1 << 8) | i_val2;
- }
- if( i_sample_rate_hint == 12 ) *pi_sample_rate = i_val1 * 1000;
- else if( i_sample_rate_hint == 13 ) *pi_sample_rate = i_val1;
- else *pi_sample_rate = i_val1 * 10;
- }
-
- /* Check the CRC-8 byte */
- if( flac_crc8( p_buf, i_header ) != p_buf[i_header] )
- {
- return 0;
- }
-
- /* Sanity check using stream info header when possible */
- if( p_sys->b_stream_info )
- {
- if( i_blocksize < p_sys->stream_info.min_blocksize ||
- i_blocksize > p_sys->stream_info.max_blocksize )
- return 0;
- }
- return i_blocksize;
-}
-
-/* Will return 0xffffffffffffffff for an invalid utf-8 sequence */
-static uint64_t read_utf8( const uint8_t *p_buf, int *pi_read )
-{
- uint64_t i_result = 0;
- unsigned i, j;
-
- if( !(p_buf[0] & 0x80) ) /* 0xxxxxxx */
- {
- i_result = p_buf[0];
- i = 0;
- }
- else if( p_buf[0] & 0xC0 && !(p_buf[0] & 0x20) ) /* 110xxxxx */
- {
- i_result = p_buf[0] & 0x1F;
- i = 1;
- }
- else if( p_buf[0] & 0xE0 && !(p_buf[0] & 0x10) ) /* 1110xxxx */
- {
- i_result = p_buf[0] & 0x0F;
- i = 2;
- }
- else if( p_buf[0] & 0xF0 && !(p_buf[0] & 0x08) ) /* 11110xxx */
- {
- i_result = p_buf[0] & 0x07;
- i = 3;
- }
- else if( p_buf[0] & 0xF8 && !(p_buf[0] & 0x04) ) /* 111110xx */
- {
- i_result = p_buf[0] & 0x03;
- i = 4;
- }
- else if( p_buf[0] & 0xFC && !(p_buf[0] & 0x02) ) /* 1111110x */
- {
- i_result = p_buf[0] & 0x01;
- i = 5;
- }
- else if( p_buf[0] & 0xFE && !(p_buf[0] & 0x01) ) /* 11111110 */
- {
- i_result = 0;
- i = 6;
- }
- else {
- return INT64_C(0xffffffffffffffff);
- }
-
- for( j = 1; j <= i; j++ )
- {
- if( !(p_buf[j] & 0x80) || (p_buf[j] & 0x40) ) /* 10xxxxxx */
- {
- return INT64_C(0xffffffffffffffff);
- }
- i_result <<= 6;
- i_result |= (p_buf[j] & 0x3F);
- }
-
- *pi_read = i;
- return i_result;
-}
-
-/* CRC-8, poly = x^8 + x^2 + x^1 + x^0, init = 0 */
-static const uint8_t flac_crc8_table[256] = {
- 0x00, 0x07, 0x0E, 0x09, 0x1C, 0x1B, 0x12, 0x15,
- 0x38, 0x3F, 0x36, 0x31, 0x24, 0x23, 0x2A, 0x2D,
- 0x70, 0x77, 0x7E, 0x79, 0x6C, 0x6B, 0x62, 0x65,
- 0x48, 0x4F, 0x46, 0x41, 0x54, 0x53, 0x5A, 0x5D,
- 0xE0, 0xE7, 0xEE, 0xE9, 0xFC, 0xFB, 0xF2, 0xF5,
- 0xD8, 0xDF, 0xD6, 0xD1, 0xC4, 0xC3, 0xCA, 0xCD,
- 0x90, 0x97, 0x9E, 0x99, 0x8C, 0x8B, 0x82, 0x85,
- 0xA8, 0xAF, 0xA6, 0xA1, 0xB4, 0xB3, 0xBA, 0xBD,
- 0xC7, 0xC0, 0xC9, 0xCE, 0xDB, 0xDC, 0xD5, 0xD2,
- 0xFF, 0xF8, 0xF1, 0xF6, 0xE3, 0xE4, 0xED, 0xEA,
- 0xB7, 0xB0, 0xB9, 0xBE, 0xAB, 0xAC, 0xA5, 0xA2,
- 0x8F, 0x88, 0x81, 0x86, 0x93, 0x94, 0x9D, 0x9A,
- 0x27, 0x20, 0x29, 0x2E, 0x3B, 0x3C, 0x35, 0x32,
- 0x1F, 0x18, 0x11, 0x16, 0x03, 0x04, 0x0D, 0x0A,
- 0x57, 0x50, 0x59, 0x5E, 0x4B, 0x4C, 0x45, 0x42,
- 0x6F, 0x68, 0x61, 0x66, 0x73, 0x74, 0x7D, 0x7A,
- 0x89, 0x8E, 0x87, 0x80, 0x95, 0x92, 0x9B, 0x9C,
- 0xB1, 0xB6, 0xBF, 0xB8, 0xAD, 0xAA, 0xA3, 0xA4,
- 0xF9, 0xFE, 0xF7, 0xF0, 0xE5, 0xE2, 0xEB, 0xEC,
- 0xC1, 0xC6, 0xCF, 0xC8, 0xDD, 0xDA, 0xD3, 0xD4,
- 0x69, 0x6E, 0x67, 0x60, 0x75, 0x72, 0x7B, 0x7C,
- 0x51, 0x56, 0x5F, 0x58, 0x4D, 0x4A, 0x43, 0x44,
- 0x19, 0x1E, 0x17, 0x10, 0x05, 0x02, 0x0B, 0x0C,
- 0x21, 0x26, 0x2F, 0x28, 0x3D, 0x3A, 0x33, 0x34,
- 0x4E, 0x49, 0x40, 0x47, 0x52, 0x55, 0x5C, 0x5B,
- 0x76, 0x71, 0x78, 0x7F, 0x6A, 0x6D, 0x64, 0x63,
- 0x3E, 0x39, 0x30, 0x37, 0x22, 0x25, 0x2C, 0x2B,
- 0x06, 0x01, 0x08, 0x0F, 0x1A, 0x1D, 0x14, 0x13,
- 0xAE, 0xA9, 0xA0, 0xA7, 0xB2, 0xB5, 0xBC, 0xBB,
- 0x96, 0x91, 0x98, 0x9F, 0x8A, 0x8D, 0x84, 0x83,
- 0xDE, 0xD9, 0xD0, 0xD7, 0xC2, 0xC5, 0xCC, 0xCB,
- 0xE6, 0xE1, 0xE8, 0xEF, 0xFA, 0xFD, 0xF4, 0xF3
-};
-
-static uint8_t flac_crc8( const uint8_t *data, unsigned len )
-{
- uint8_t crc = 0;
-
- while(len--)
- crc = flac_crc8_table[crc ^ *data++];
-
- return crc;
-}
-
-#ifdef USE_LIBFLAC