* all : a demux for aac stream ( raw aac with adts headers ). For now

it has a capability equal to 0 because it conflicts with PS, so you need
to force it.

modules/demux/aac/.cvsignore

+.dep
+*.lo
+*.o.*
+*.lo.*

modules/demux/aac/Makefile

+aac_SOURCES = demux.c

modules/demux/aac/demux.c

+/*****************************************************************************
+ * demux.c : Raw aac Stream input module for vlc
+ *****************************************************************************
+ * Copyright (C) 2001 VideoLAN
+ * $Id: demux.c,v 1.1 2002/08/12 16:59:15 fenrir Exp $
+ *
+ * Authors: Laurent Aimar <fenrir@via.ecp.fr>
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
+ *****************************************************************************/
+
+/*****************************************************************************
+ * Preamble
+ *****************************************************************************/
+#include <stdlib.h>                                      /* malloc(), free() */
+#include <string.h>
+
+#include <vlc/vlc.h>
+#include <vlc/input.h>
+
+#include <sys/types.h>
+
+/*****************************************************************************
+ * Local prototypes
+ *****************************************************************************/
+static int  Activate ( vlc_object_t * );
+static int  Demux ( input_thread_t * );
+
+
+/*****************************************************************************
+ * Module descriptor
+ *****************************************************************************/
+vlc_module_begin();
+    set_description( _("AAC stream demux" ) );
+    set_capability( "demux", 0 );
+    set_callbacks( Activate, NULL );
+    add_shortcut( "aac" );
+vlc_module_end();
+
+/*****************************************************************************
+ * Definitions of structures  and functions used by this plugins 
+ *****************************************************************************/
+
+/* XXX set this to 0 to avoid problem with PS XXX */
+/* but with some file or web radio will failed to detect */
+/* it's you to choose */
+#define AAC_MAXTESTPOS    0
+
+static int i_aac_samplerate[16] =
+{
+    96000, 88200, 64000, 48000, 44100, 32000, 
+    24000, 22050, 16000, 12000, 11025, 8000,
+    7350,  0,     0,     0
+};
+
+typedef struct adts_header_s
+{
+    int i_id;
+    int i_framelength;
+    int i_layer;
+    int i_protection_absent;
+    int i_profile;
+    int i_samplerate_index;
+    int i_private_bit;
+    int i_channel_configuration;
+    int i_original;
+    int i_home;
+    int i_emphasis;
+    int i_copyright_identification_bit;
+    int i_copyright_identification_start;
+    int i_aac_frame_length;
+    int i_adts_buffer_fullness;
+    int i_no_raw_data_blocks_in_frame;
+    int i_crc_check;
+                    
+} adts_header_t;
+
+/* Not yet used */
+typedef struct adif_header_s
+{
+    int b_copyright_id_present;
+    u8  i_copyright_id[10];
+    
+    int b_original_copy;
+
+    int i_home;
+    int i_bitstream_type;
+    int i_bitrate;
+    int i_num_program_config_elements;
+    int adif_buffer_fullness;
+
+//    program_config_element
+
+
+} adif_header_t;
+
+struct demux_sys_t
+{
+    mtime_t i_pts;
+
+    es_descriptor_t         *p_es;
+
+    int                     b_adif_header;
+    adif_header_t           adif_header;
+
+    int                     b_adts_header;
+    adts_header_t           adts_header;
+
+    /* extracted information */
+    int i_samplerate_index;
+    int i_object_type;
+    int i_samplerate;
+    int i_channels;
+    int i_framelength;
+    int i_aac_frame_length;
+};
+
+/****************************************************************************
+ * bit_* : function to get a bitstream from a memory buffer
+ ****************************************************************************
+ *
+ ****************************************************************************/ 
+typedef struct bit_s
+{
+    u8 *p_buffer;
+    int i_buffer;
+    int i_mask;
+} bit_t;
+
+static void bit_init( bit_t *p_bit,
+                      u8    *p_buffer,
+                      int   i_buffer )
+{
+    p_bit->p_buffer = p_buffer;
+    p_bit->i_buffer = i_buffer;
+    p_bit->i_mask = 0x80;
+}
+
+static u32 bit_get( bit_t *p_bit )
+{
+    u32 i_bit;
+    if( p_bit->i_buffer <= 0 )
+    {
+        return( 0 );
+    }
+    i_bit = ( p_bit->p_buffer[0]&p_bit->i_mask ) ? 1 : 0;
+    
+    p_bit->i_mask >>= 1;
+    if( !p_bit->i_mask )
+    {
+        p_bit->p_buffer++;
+        p_bit->i_buffer--;
+        p_bit->i_mask = 0x80;
+    }
+    return( i_bit );
+}
+
+static u32 bit_gets( bit_t *p_bit, int i_count )
+{
+    u32 i_bits;
+    i_bits = 0;
+    for( ; i_count > 0; i_count-- )
+    {
+        i_bits = ( i_bits << 1 )|bit_get( p_bit );
+    }
+    return( i_bits );
+}
+
+/*****************************************************************************
+ * Function to manipulate stream easily
+ *****************************************************************************
+ *
+ * SkipBytes : skip bytes :) not yet uoptimised ( read bytes to be skipped )
+ *
+ * ReadPes : read data and make a PES
+ * 
+ *****************************************************************************/
+static int SkipBytes( input_thread_t *p_input, int i_size )
+{
+    data_packet_t *p_data;
+    int i_read;
+
+    while( i_size > 0 )
+    {
+        i_read = input_SplitBuffer(p_input, &p_data, __MIN( i_size, 1024 ) );
+        if( i_read <= 0 )
+        {
+            return( 0 );
+        }
+        input_DeletePacket( p_input->p_method_data, p_data );
+        i_size -= i_read;
+    }
+    return( 1 );
+}
+
+static int ReadPES( input_thread_t *p_input, 
+                    pes_packet_t **pp_pes, 
+                    int i_size )
+{
+    pes_packet_t *p_pes;
+
+    *pp_pes = NULL;
+        
+    if( !(p_pes = input_NewPES( p_input->p_method_data )) )
+    {
+        msg_Err( p_input, "cannot allocate new PES" );
+        return( 0 );
+    }
+
+    while( i_size > 0 )
+    {
+        data_packet_t   *p_data;
+        int i_read;
+
+        if( (i_read = input_SplitBuffer( p_input, 
+                                         &p_data, 
+                                         __MIN( i_size, 1024 ) ) ) <= 0 )
+        {
+            input_DeletePES( p_input->p_method_data, p_pes );
+            return( 0 );
+        }
+        if( !p_pes->p_first )
+        {
+            p_pes->p_first = p_data;
+            p_pes->i_nb_data = 1;
+            p_pes->i_pes_size = i_read;
+        }
+        else
+        {
+            p_pes->p_last->p_next  = p_data;
+            p_pes->i_nb_data++;
+            p_pes->i_pes_size += i_read;
+        }
+        p_pes->p_last  = p_data;
+        i_size -= i_read;
+    }
+    *pp_pes = p_pes;
+    return( 1 );
+}
+
+/*****************************************************************************
+ * GetADIF: find and load adif header if present
+ *****************************************************************************/
+static int GetADIF( input_thread_t *p_input,
+                    adif_header_t  *p_adif )
+{
+    u8  *p_peek;
+    int i_size;
+
+    if( ( i_size = input_Peek( p_input, &p_peek, 60 ) ) < 60  )
+    {
+        /* it's false, min size is 11 byte but easier ;) */
+        return( 0 );
+    }
+    if( ( p_peek[0] != 'A' )||( p_peek[1] != 'D' )||
+        ( p_peek[2] != 'I' )||( p_peek[3] != 'F' ) )
+    {
+        return( 0 );
+    }
+    
+    /* we now that we have an adif header */
+    
+//    return( 1 );
+    return( 0 ); /* need some work */
+}
+
+/*****************************************************************************
+ * GetADTS: find and load adts header 
+ *****************************************************************************/
+#define ADTS_HEADERSIZE 10 /* 8+2 for crc */
+static int GetADTS( input_thread_t  *p_input,
+                    adts_header_t   *p_adts,
+                    int             i_max_pos,
+                    int             *pi_skip )
+{
+    u8  *p_peek;
+    int i_size;
+    bit_t bit;
+
+    if( ( i_size = input_Peek( p_input, &p_peek, i_max_pos + ADTS_HEADERSIZE ) )
+            < ADTS_HEADERSIZE )
+    {
+        return( 0 );
+    }
+    *pi_skip = 0;
+    for( ; ; )
+    {
+        if( i_size < ADTS_HEADERSIZE )
+        {
+            return( 0 );
+        }
+        if( ( p_peek[0] != 0xff )||
+            ( ( p_peek[1]&0xf6 ) != 0xf0 ) ) /* Layer == 0 */
+        {
+            p_peek++;
+            i_size--;
+            *pi_skip += 1;
+            continue;
+        }
+        /* we have find an adts header, load it */
+        break;
+    }
+
+    bit_init( &bit, p_peek, i_size );
+    bit_gets( &bit, 12 ); /* synchro bits */
+    
+    p_adts->i_id        = bit_get( &bit );
+    p_adts->i_layer     = bit_gets( &bit, 2);
+    p_adts->i_protection_absent = bit_get( &bit );
+    p_adts->i_profile           = bit_gets( &bit, 2 );
+    p_adts->i_samplerate_index  = bit_gets( &bit, 4);
+    p_adts->i_private_bit       = bit_get( &bit );
+    p_adts->i_channel_configuration = bit_gets( &bit, 3);
+    p_adts->i_original  = bit_get( &bit );
+    p_adts->i_home      = bit_get( &bit );
+    if( p_adts->i_id == 0 )
+    {
+        p_adts->i_emphasis = bit_gets( &bit, 2);
+    }
+
+    p_adts->i_copyright_identification_bit   = bit_get( &bit );
+    p_adts->i_copyright_identification_start = bit_get( &bit );
+    p_adts->i_aac_frame_length               = bit_gets( &bit, 13 );
+    p_adts->i_adts_buffer_fullness           = bit_gets( &bit, 11 );
+    p_adts->i_no_raw_data_blocks_in_frame    = bit_gets( &bit, 2 );
+
+    if( p_adts->i_protection_absent == 0 )
+    {
+        p_adts->i_crc_check = bit_gets( &bit, 16 );
+    }
+    return( 1 );
+}
+
+static void ExtractConfiguration( demux_sys_t *p_aac )
+{
+    if( p_aac->b_adif_header )
+    {
+
+    }
+    if( p_aac->b_adts_header )
+    {
+        p_aac->i_samplerate_index = p_aac->adts_header.i_samplerate_index;
+        p_aac->i_object_type = p_aac->adts_header.i_profile;
+        p_aac->i_samplerate  = i_aac_samplerate[p_aac->i_samplerate_index];
+        p_aac->i_channels    = p_aac->adts_header.i_channel_configuration;       
+        if( p_aac->i_channels > 6 )
+        {
+            /* I'm not sure of that, got from faad */
+            p_aac->i_channels = 2;
+        }
+        p_aac->i_aac_frame_length = p_aac->adts_header.i_aac_frame_length;
+        p_aac->i_framelength = 1024;
+    }
+    /* FIXME FIXME for LD, but LD = ?
+    if( p_aac->i_object_type == LD )
+    {
+        p_aac->i_framelength /= 2;
+    }
+    */
+}
+
+/****************************************************************************
+ * SkipID3Tag : check if an ID3 header is present and skip it
+ ****************************************************************************
+ * 
+ * Author : Sigmund Augdal
+ * 
+ ****************************************************************************/
+ 
+static int SkipID3Tag( input_thread_t *p_input )
+{
+    int i_count;
+    byte_t *p_peek;
+    byte_t version, revision;
+    int b_footer;
+    int i_size;
+
+    /* get 10 byte id3 header */    
+    if( ( i_count = input_Peek( p_input, &p_peek, 10 ) ) < 10 )
+    {
+        msg_Err( p_input, "cannot peek()" );
+        return( -1 );
+    }
+    
+    if ( !( (p_peek[0] == 0x49) && (p_peek[1] == 0x44) && (p_peek[2] == 0x33)))
+    {
+        return( 0 );
+    }
+    
+    version = p_peek[3];  /* These may become usfull later, */
+    revision = p_peek[4]; /* but we ignore them for now */
+
+    b_footer = p_peek[5] & 0x10;
+    i_size = (p_peek[6] << 21) +
+             (p_peek[7] << 14) +
+             (p_peek[8] << 7) +
+             p_peek[9];  /* Is this safe? */
+    if ( b_footer )
+    {
+        i_size += 10;
+    }
+    i_size += 10;
+    msg_Dbg( p_input, "ID3 tag found, skiping %d bytes", i_size );
+    if ( input_Peek( p_input, &p_peek, i_size ) < i_size )
+    {
+        msg_Err( p_input, "cannot peek()" );
+        return( -1 );
+    }
+        
+    p_input->p_current_data += i_size; /* seek passed end of ID3 tag */
+
+    return (0);
+}
+
+/****************************************************************************
+ * CheckPS : check if this stream could be some ps, 
+ *           yes it's ugly ...  but another idea ?
+ *
+ *           XXX it seems that aac stream always match ...
+ *
+ ****************************************************************************/
+
+static int CheckPS( input_thread_t *p_input )
+{
+    u8 *p_peek;
+    int i_size = input_Peek( p_input, &p_peek, 8196 );
+
+    while( i_size >  4 )
+    {
+        if( ( p_peek[0] == 0 ) && ( p_peek[1] == 0 )&&
+            ( p_peek[2] == 1 ) && ( p_peek[3] >= 0xb9 ) )
+        {
+            return( 1 ); /* Perhaps some ps stream */
+        }
+        p_peek++;
+       i_size--; 
+    }
+    return( 0 );
+}
+
+/*****************************************************************************
+ * Activate: initializes AAC demux structures
+ *****************************************************************************/
+static int Activate( vlc_object_t * p_this )
+{
+    input_thread_t * p_input = (input_thread_t *)p_this;
+    demux_sys_t * p_aac;
+    input_info_category_t * p_category;
+
+    int i_skip;
+    int b_forced;
+
+    /* Set the demux function */
+    p_input->pf_demux = Demux;
+
+    /* Initialize access plug-in structures. */
+    if( p_input->i_mtu == 0 )
+    {
+    /* Improve speed. */
+        p_input->i_bufsize = INPUT_DEFAULT_BUFSIZE;
+    }
+
+    b_forced = ( ( *p_input->psz_demux )&&
+                 ( !strncmp( p_input->psz_demux, "aac", 10 ) ) ) ? 1 : 0;
+    
+    /* check if it can be a ps stream */
+    if( !b_forced && CheckPS(  p_input ) )
+    {
+        return( -1 );
+    }
+    
+    /* skip possible id3 header */    
+    if ( SkipID3Tag( p_input ) )
+    {
+        return -1;
+    }
+    /* allocate p_aac */
+    if( !( p_aac = malloc( sizeof( demux_sys_t ) ) ) )
+    {
+        msg_Err( p_input, "out of memory" );
+        return( -1 );
+    }
+    memset( p_aac, 0, sizeof( demux_sys_t ) );
+    
+    /* Now check for adif/adts header */
+    i_skip = 0;
+    if( GetADIF( p_input, &p_aac->adif_header ) )
+    {
+        p_aac->b_adif_header = 1;
+        msg_Err( p_input,
+                 "found ADIF header (unsupported)" );
+        free( p_aac );
+        return( -1 );
+    }
+    else
+    if( GetADTS( p_input, 
+                 &p_aac->adts_header, 
+                 b_forced ? 8000 : 0,
+                 &i_skip  ) )
+    {
+        p_aac->b_adts_header = 1;
+        msg_Info( p_input,
+                  "found ADTS header" );
+    }
+    else
+    {
+        msg_Warn( p_input,
+                  "AAC module discarded (no header found)" );
+        free( p_aac );
+        return( -1 );
+    }
+    ExtractConfiguration( p_aac );
+
+    vlc_mutex_lock( &p_input->stream.stream_lock );
+    if( input_InitStream( p_input, 0 ) == -1)
+    {
+        msg_Err( p_input, "cannot init stream" );
+        return( -1 );
+    }    
+    if( input_AddProgram( p_input, 0, 0) == NULL )
+    {
+        msg_Err( p_input, "cannot add program" );
+        return( -1 );
+    }
+    p_input->stream.pp_programs[0]->b_is_ok = 0;
+    p_input->stream.p_selected_program = p_input->stream.pp_programs[0];
+    
+    /* create our ES */ 
+    p_aac->p_es = input_AddES( p_input, 
+                               p_input->stream.p_selected_program, 
+                               1, /* id */
+                               0 );
+    if( !p_aac->p_es )
+    {
+        vlc_mutex_unlock( &p_input->stream.stream_lock );
+        msg_Err( p_input, "out of memory" );
+        return( -1 );
+    }
+    
+    p_aac->p_es->i_stream_id = 1;
+    p_aac->p_es->i_fourcc = VLC_FOURCC( 'm', 'p', '4', 'a' );
+    p_aac->p_es->i_cat = AUDIO_ES;
+    input_SelectES( p_input, p_aac->p_es );
+
+    p_input->stream.p_selected_program->b_is_ok = 1;
+    vlc_mutex_unlock( &p_input->stream.stream_lock );
+
+
+    
+    vlc_mutex_lock( &p_input->stream.stream_lock );
+    if( p_aac->b_adif_header )
+    {
+        p_input->stream.i_mux_rate = 0 / 50;
+    }
+    if( p_aac->b_adts_header )
+    {
+        p_input->stream.i_mux_rate = 0 / 50;
+    }
+    vlc_mutex_unlock( &p_input->stream.stream_lock );
+#if 0
+    /* FIXME FIXME FIXME FIXME FIXME FIXME FIXME */
+    /* if i don't do that, it don't work correctly but why ??? */
+    if( p_input->stream.b_seekable )
+    {
+        p_input->pf_seek( p_input, 0 );
+        input_AccessReinit( p_input );
+    }
+    /* FIXME FIXME FIXME FIXME FIXME FIXME FIXME */
+#endif
+
+    /* all is ok :)) */
+    if( p_aac->b_adif_header )
+    {
+    }
+
+    if( p_aac->b_adts_header )
+    {
+        msg_Dbg( p_input,
+                 "audio AAC MPEG-%d layer-%d  %d channels %dHz",
+                 p_aac->adts_header.i_id == 1 ? 2 : 4,
+                 4 - p_aac->adts_header.i_layer, /* it's always 4 in fact */
+                 p_aac->i_channels,
+                 p_aac->i_samplerate );
+
+        vlc_mutex_lock( &p_input->stream.stream_lock );
+        p_category = input_InfoCategory( p_input, "aac" );
+    
+        input_AddInfo( p_category, "input type", "MPEG-%d AAC",
+                       p_aac->adts_header.i_id == 1 ? 2 : 4 );
+
+        input_AddInfo( p_category, "layer", "%d", 
+                       4 - p_aac->adts_header.i_layer );
+        input_AddInfo( p_category, "channels", "%d", 
+                       p_aac->i_channels );
+        input_AddInfo( p_category, "sample rate", "%dHz", 
+                       p_aac->i_samplerate );
+
+        vlc_mutex_unlock( &p_input->stream.stream_lock );
+    }
+
+    p_input->p_demux_data = p_aac;
+    
+
+    return( 0 );
+}
+
+/*****************************************************************************
+ * Demux: reads and demuxes data packets
+ *****************************************************************************
+ * Returns -1 in case of error, 0 in case of EOF, 1 otherwise
+ *****************************************************************************/
+static int Demux( input_thread_t * p_input )
+{
+    int i_skip;
+    int i_found;
+    
+    pes_packet_t    *p_pes;
+    demux_sys_t *p_aac = p_input->p_demux_data;
+
+    /* Get a frame */
+    if( p_aac->b_adif_header )
+    {
+        i_skip = 0;
+        return( -1 ); /* FIXME */
+    }
+    else
+    if( p_aac->b_adts_header )
+    {
+        i_found = GetADTS( p_input, 
+                           &p_aac->adts_header,
+                           8000,
+                           &i_skip );
+    }
+    else
+    {
+        return( -1 );
+    }
+    ExtractConfiguration( p_aac );
+   
+    /* skip garbage bytes */
+    if( i_skip > 0 )
+    {
+        msg_Dbg( p_input,
+                 "skipping %d bytes",
+                 i_skip );
+        SkipBytes( p_input, i_skip );
+    }
+
+    if( !i_found )
+    {
+        msg_Info( p_input, "can't find next frame" );
+        return( 0 );
+    }
+    
+    input_ClockManageRef( p_input,
+                          p_input->stream.p_selected_program,
+                          p_aac->i_pts );
+   
+    if( !ReadPES( p_input, &p_pes, p_aac->i_aac_frame_length ) )
+    {
+        msg_Err( p_input,
+                 "cannot read data" );
+        return( -1 );
+    }
+    p_pes->i_dts =
+        p_pes->i_pts = input_ClockGetTS( p_input,
+                                         p_input->stream.p_selected_program,
+                                         p_aac->i_pts );
+
+    if( !p_aac->p_es->p_decoder_fifo )
+    {
+        msg_Err( p_input, "no audio decoder" );
+        input_DeletePES( p_input->p_method_data, p_pes );
+        return( -1 ); /* perhaps not, it's my choice */
+    }
+    else
+    {
+        input_DecodePES( p_aac->p_es->p_decoder_fifo, p_pes );
+    }
+
+    /* Update date information */
+    p_aac->i_pts += (mtime_t)90000 * 
+                    (mtime_t)p_aac->i_framelength /
+                    (mtime_t)p_aac->i_samplerate;
+
+    return( 1 );
+}
+