/***************************************************************************** * flac.c: flac packetizer module. ***************************************************************************** * Copyright (C) 1999-2001 VLC authors and VideoLAN * $Id$ * * Authors: Gildas Bazin * Sigmund Augdal Helberg * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation; either version 2.1 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with this program; if not, write to the Free Software Foundation, * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA. *****************************************************************************/ /***************************************************************************** * Preamble *****************************************************************************/ #ifdef HAVE_CONFIG_H # include "config.h" #endif #include #include #include #include #include #include "packetizer_helper.h" /***************************************************************************** * Module descriptor *****************************************************************************/ static int Open ( vlc_object_t * ); static void Close( vlc_object_t * ); vlc_module_begin() set_category( CAT_SOUT ) set_subcategory( SUBCAT_SOUT_PACKETIZER ) set_description( N_("Flac audio packetizer") ) set_capability( "packetizer", 50 ) set_callbacks( Open, Close ) vlc_module_end() /***************************************************************************** * decoder_sys_t : FLAC decoder descriptor *****************************************************************************/ #define MAX_FLAC_HEADER_SIZE 16 struct decoder_sys_t { /* * Input properties */ int i_state; block_bytestream_t bytestream; /* * FLAC properties */ struct { unsigned min_blocksize, max_blocksize; unsigned min_framesize, max_framesize; unsigned sample_rate; unsigned channels; unsigned bits_per_sample; } stream_info; bool b_stream_info; /* * Common properties */ date_t end_date; mtime_t i_pts; int i_frame_length; size_t i_frame_size; unsigned int i_rate, i_channels, i_bits_per_sample; }; static const int pi_channels_maps[9] = { 0, AOUT_CHAN_CENTER, AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT, AOUT_CHAN_CENTER | AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT, AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT, AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT, AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT | AOUT_CHAN_LFE, AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT | AOUT_CHAN_MIDDLELEFT | AOUT_CHAN_MIDDLERIGHT, AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT | AOUT_CHAN_CENTER | AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT | AOUT_CHAN_MIDDLELEFT | AOUT_CHAN_MIDDLERIGHT | AOUT_CHAN_LFE }; /***************************************************************************** * Local prototypes *****************************************************************************/ static block_t *Packetize( decoder_t *, block_t ** ); static int SyncInfo( decoder_t *, uint8_t *, unsigned int *, unsigned int *, unsigned int * ); static uint64_t read_utf8( const uint8_t *p_buf, int *pi_read ); static uint8_t flac_crc8( const uint8_t *data, unsigned len ); static int Open( vlc_object_t *p_this ) { decoder_t *p_dec = (decoder_t*)p_this; decoder_sys_t *p_sys; if( p_dec->fmt_in.i_codec != VLC_CODEC_FLAC ) return VLC_EGENERIC; /* */ p_dec->p_sys = p_sys = malloc(sizeof(*p_sys)); if( !p_sys ) return VLC_ENOMEM; date_Set( &p_sys->end_date, 0 ); p_sys->i_state = STATE_NOSYNC; p_sys->b_stream_info = false; p_sys->i_pts = VLC_TS_INVALID; block_BytestreamInit( &p_sys->bytestream ); /* */ es_format_Copy( &p_dec->fmt_out, &p_dec->fmt_in ); p_dec->fmt_out.i_cat = AUDIO_ES; p_dec->fmt_out.i_codec = VLC_CODEC_FLAC; /* */ p_dec->pf_decode_audio = NULL; p_dec->pf_packetize = Packetize; return VLC_SUCCESS; } static void Close( vlc_object_t *p_this ) { decoder_t *p_dec = (decoder_t *)p_this; decoder_sys_t *p_sys = p_dec->p_sys; block_BytestreamRelease( &p_sys->bytestream ); free( p_sys ); } /***************************************************************************** * ProcessHeader: process Flac header. *****************************************************************************/ static void ProcessHeader( decoder_t *p_dec ) { decoder_sys_t *p_sys = p_dec->p_sys; bs_t bs; int i_extra = p_dec->fmt_in.i_extra; char *p_extra = p_dec->fmt_in.p_extra; if (i_extra > 8 && !memcmp(p_extra, "fLaC", 4)) { i_extra -= 8; p_extra += 8; } if( p_dec->fmt_in.i_extra < 14 ) return; bs_init( &bs, p_extra, i_extra); p_sys->stream_info.min_blocksize = bs_read( &bs, 16 ); p_sys->stream_info.max_blocksize = bs_read( &bs, 16 ); p_sys->stream_info.min_framesize = bs_read( &bs, 24 ); p_sys->stream_info.max_framesize = bs_read( &bs, 24 ); p_sys->stream_info.sample_rate = bs_read( &bs, 20 ); p_sys->stream_info.channels = bs_read( &bs, 3 ) + 1; p_sys->stream_info.bits_per_sample = bs_read( &bs, 5 ) + 1; p_sys->b_stream_info = true; p_dec->fmt_out.i_extra = i_extra; p_dec->fmt_out.p_extra = xrealloc( p_dec->fmt_out.p_extra, i_extra ); memcpy( p_dec->fmt_out.p_extra, p_extra, i_extra ); } /* */ static block_t *Packetize( decoder_t *p_dec, block_t **pp_block ) { decoder_sys_t *p_sys = p_dec->p_sys; uint8_t p_header[MAX_FLAC_HEADER_SIZE]; block_t *p_sout_block; if( !pp_block || !*pp_block ) return NULL; if( (*pp_block)->i_flags&(BLOCK_FLAG_DISCONTINUITY|BLOCK_FLAG_CORRUPTED) ) { if( (*pp_block)->i_flags&BLOCK_FLAG_CORRUPTED ) { p_sys->i_state = STATE_NOSYNC; block_BytestreamEmpty( &p_sys->bytestream ); } date_Set( &p_sys->end_date, 0 ); block_Release( *pp_block ); return NULL; } if( !p_sys->b_stream_info ) ProcessHeader( p_dec ); if( p_sys->stream_info.channels > 8 ) { msg_Err( p_dec, "This stream uses too many audio channels" ); return NULL; } if( !date_Get( &p_sys->end_date ) && (*pp_block)->i_pts <= VLC_TS_INVALID ) { /* We've just started the stream, wait for the first PTS. */ block_Release( *pp_block ); return NULL; } else if( !date_Get( &p_sys->end_date ) ) { /* The first PTS is as good as anything else. */ p_sys->i_rate = p_dec->fmt_out.audio.i_rate; date_Init( &p_sys->end_date, p_sys->i_rate, 1 ); date_Set( &p_sys->end_date, (*pp_block)->i_pts ); } block_BytestreamPush( &p_sys->bytestream, *pp_block ); while( 1 ) { int previous_size; switch( p_sys->i_state ) { case STATE_NOSYNC: while( block_PeekBytes( &p_sys->bytestream, p_header, 2 ) == VLC_SUCCESS ) { if( p_header[0] == 0xFF && (p_header[1] & 0xFE) == 0xF8 ) { p_sys->i_state = STATE_SYNC; break; } block_SkipByte( &p_sys->bytestream ); } if( p_sys->i_state != STATE_SYNC ) { block_BytestreamFlush( &p_sys->bytestream ); /* Need more data */ return NULL; } case STATE_SYNC: /* New frame, set the Presentation Time Stamp */ p_sys->i_pts = p_sys->bytestream.p_block->i_pts; if( p_sys->i_pts > VLC_TS_INVALID && p_sys->i_pts != date_Get( &p_sys->end_date ) ) { date_Set( &p_sys->end_date, p_sys->i_pts ); } p_sys->i_state = STATE_HEADER; case STATE_HEADER: /* Get FLAC frame header (MAX_FLAC_HEADER_SIZE bytes) */ if( block_PeekBytes( &p_sys->bytestream, p_header, MAX_FLAC_HEADER_SIZE ) != VLC_SUCCESS ) { /* Need more data */ return NULL; } /* Check if frame is valid and get frame info */ p_sys->i_frame_length = SyncInfo( p_dec, p_header, &p_sys->i_channels, &p_sys->i_rate, &p_sys->i_bits_per_sample ); if( !p_sys->i_frame_length ) { msg_Dbg( p_dec, "emulated sync word" ); block_SkipByte( &p_sys->bytestream ); p_sys->i_state = STATE_NOSYNC; break; } if( p_sys->i_rate != p_dec->fmt_out.audio.i_rate ) { p_dec->fmt_out.audio.i_rate = p_sys->i_rate; const mtime_t i_end_date = date_Get( &p_sys->end_date ); date_Init( &p_sys->end_date, p_sys->i_rate, 1 ); date_Set( &p_sys->end_date, i_end_date ); } p_sys->i_state = STATE_NEXT_SYNC; p_sys->i_frame_size = p_sys->b_stream_info && p_sys->stream_info.min_framesize > 0 ? p_sys->stream_info.min_framesize : 1; case STATE_NEXT_SYNC: /* TODO: If pp_block == NULL, flush the buffer without checking the * next sync word */ previous_size = 0; /* Try to return the biggest frame */ /* Check if next expected frame contains the sync word */ while( block_PeekOffsetBytes( &p_sys->bytestream, p_sys->i_frame_size, p_header, MAX_FLAC_HEADER_SIZE ) == VLC_SUCCESS ) { if( p_header[0] == 0xFF && (p_header[1] & 0xFE) == 0xF8 ) { /* Check if frame is valid and get frame info */ int i_frame_length = SyncInfo( p_dec, p_header, &p_sys->i_channels, &p_sys->i_rate, &p_sys->i_bits_per_sample ); if( i_frame_length ) { if( !p_sys->b_stream_info || p_sys->stream_info.max_framesize <= 0 ) { /* Stop immediately if we don't know the maximum framesize */ p_sys->i_state = STATE_SEND_DATA; break; } previous_size = p_sys->i_frame_size; } } p_sys->i_frame_size++; if( p_sys->b_stream_info && p_sys->stream_info.max_framesize > 0 && p_sys->i_frame_size > p_sys->stream_info.max_framesize ) break; } if (previous_size) { /* Use the largest frame size */ p_sys->i_frame_size = previous_size; p_sys->i_state = STATE_SEND_DATA; } if( p_sys->i_state != STATE_SEND_DATA ) { if( p_sys->b_stream_info && p_sys->stream_info.max_framesize > 0 && p_sys->i_frame_size > p_sys->stream_info.max_framesize ) { block_SkipByte( &p_sys->bytestream ); p_sys->i_state = STATE_NOSYNC; return NULL; } /* Need more data */ return NULL; } case STATE_SEND_DATA: p_sout_block = block_Alloc( p_sys->i_frame_size ); /* Copy the whole frame into the buffer. When we reach this point * we already know we have enough data available. */ block_GetBytes( &p_sys->bytestream, p_sout_block->p_buffer, p_sys->i_frame_size ); /* Make sure we don't reuse the same pts twice */ if( p_sys->i_pts == p_sys->bytestream.p_block->i_pts ) p_sys->i_pts = p_sys->bytestream.p_block->i_pts = VLC_TS_INVALID; p_dec->fmt_out.audio.i_channels = p_sys->i_channels; p_dec->fmt_out.audio.i_physical_channels = p_dec->fmt_out.audio.i_original_channels = pi_channels_maps[p_sys->stream_info.channels]; /* So p_block doesn't get re-added several times */ *pp_block = block_BytestreamPop( &p_sys->bytestream ); p_sys->i_state = STATE_NOSYNC; /* Date management */ p_sout_block->i_pts = p_sout_block->i_dts = date_Get( &p_sys->end_date ); date_Increment( &p_sys->end_date, p_sys->i_frame_length ); p_sout_block->i_length = date_Get( &p_sys->end_date ) - p_sout_block->i_pts; return p_sout_block; } } return NULL; } /***************************************************************************** * SyncInfo: parse FLAC sync info *****************************************************************************/ static int SyncInfo( decoder_t *p_dec, uint8_t *p_buf, unsigned int * pi_channels, unsigned int * pi_sample_rate, unsigned 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; /* Check syncword */ if( p_buf[0] != 0xFF || (p_buf[1] & 0xFE) != 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( p_sys->b_stream_info && p_sys->stream_info.min_blocksize == p_sys->stream_info.max_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; } if( p_sys->b_stream_info && ( i_blocksize < p_sys->stream_info.min_blocksize || i_blocksize > p_sys->stream_info.max_blocksize ) ) return 0; /* 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: *pi_sample_rate = 88200; break; case 2: *pi_sample_rate = 176400; break; case 3: *pi_sample_rate = 192000; 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 ) { if( ( i_temp & 7 ) >= 3 ) return 0; *pi_channels = 2; } else { *pi_channels = i_temp + 1; } /* 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; /* Check Sample/Frame number */ if( read_utf8( &p_buf[i_header++], &i_read ) == INT64_C(0xffffffffffffffff) ) return 0; 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; if( *pi_bits_per_sample != p_sys->stream_info.bits_per_sample ) return 0; if( *pi_sample_rate != p_sys->stream_info.sample_rate ) 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; }