mp4.c

uclinux 下的vlc播放器源代码

/*****************************************************************************
 * mp4.c: mp4/mov muxer
 *****************************************************************************
 * Copyright (C) 2001, 2002, 2003, 2006 the VideoLAN team
 * $Id: mp4.c 16767 2006-09-21 14:32:45Z hartman $
 *
 * Authors: Laurent Aimar <[e-mail]>
 *          Gildas Bazin <gbazin at videolan dot org>
 *
 * 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., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
 *****************************************************************************/

/*****************************************************************************
 * Preamble
 *****************************************************************************/
#include <stdlib.h>
#include <string.h>

#include <vlc/vlc.h>
#include <vlc/input.h>
#include <vlc/sout.h>

#ifdef HAVE_TIME_H
#include <time.h>
#endif

#include "iso_lang.h"
#include "vlc_meta.h"

/*****************************************************************************
 * Module descriptor
 *****************************************************************************/
#define FASTSTART_TEXT N_("Create \"Fast Start\" files")
#define FASTSTART_LONGTEXT N_( \
    "Create \"Fast Start\" files. " \
    "\"Fast Start\" files are optimized for downloads and allow the user " \
    "to start previewing the file while it is downloading.")

static int  Open   ( vlc_object_t * );
static void Close  ( vlc_object_t * );

#define SOUT_CFG_PREFIX "sout-mp4-"

vlc_module_begin();
    set_description( _("MP4/MOV muxer") );
    set_category( CAT_SOUT );
    set_subcategory( SUBCAT_SOUT_MUX );
    set_shortname( "MP4" );

    add_bool( SOUT_CFG_PREFIX "faststart", 1, NULL,
              FASTSTART_TEXT, FASTSTART_LONGTEXT,
              VLC_TRUE );
    set_capability( "sout mux", 5 );
    add_shortcut( "mp4" );
    add_shortcut( "mov" );
    add_shortcut( "3gp" );
    set_callbacks( Open, Close );
vlc_module_end();

/*****************************************************************************
 * Exported prototypes
 *****************************************************************************/
static const char *ppsz_sout_options[] = {
    "faststart", NULL
};

static int Control( sout_mux_t *, int, va_list );
static int AddStream( sout_mux_t *, sout_input_t * );
static int DelStream( sout_mux_t *, sout_input_t * );
static int Mux      ( sout_mux_t * );

/*****************************************************************************
 * Local prototypes
 *****************************************************************************/
typedef struct
{
    uint64_t i_pos;
    int      i_size;

    mtime_t  i_pts_dts;
    mtime_t  i_length;
    unsigned int i_flags;

} mp4_entry_t;

typedef struct
{
    es_format_t   fmt;
    int           i_track_id;

    /* index */
    unsigned int i_entry_count;
    unsigned int i_entry_max;
    mp4_entry_t  *entry;
    int64_t      i_length_neg;

    /* stats */
    int64_t      i_dts_start;
    int64_t      i_duration;

    /* for later stco fix-up (fast start files) */
    uint64_t i_stco_pos;
    vlc_bool_t b_stco64;

    /* for h264 */
    struct
    {
        int     i_profile;
        int     i_profile_compat;
        int     i_level;

        int     i_sps;
        uint8_t *sps;
        int     i_pps;
        uint8_t *pps;
    } avc;

    /* for spu */
    int64_t i_last_dts;

} mp4_stream_t;

struct sout_mux_sys_t
{
    vlc_bool_t b_mov;
    vlc_bool_t b_3gp;
    vlc_bool_t b_64_ext;
    vlc_bool_t b_fast_start;

    uint64_t i_mdat_pos;
    uint64_t i_pos;

    int64_t  i_dts_start;

    int          i_nb_streams;
    mp4_stream_t **pp_streams;
};

typedef struct bo_t
{
    vlc_bool_t b_grow;

    int        i_buffer_size;
    int        i_buffer;
    uint8_t    *p_buffer;

} bo_t;

static void bo_init     ( bo_t *, int , uint8_t *, vlc_bool_t  );
static void bo_add_8    ( bo_t *, uint8_t );
static void bo_add_16be ( bo_t *, uint16_t );
static void bo_add_24be ( bo_t *, uint32_t );
static void bo_add_32be ( bo_t *, uint32_t );
static void bo_add_64be ( bo_t *, uint64_t );
static void bo_add_fourcc(bo_t *, char * );
static void bo_add_bo   ( bo_t *, bo_t * );
static void bo_add_mem  ( bo_t *, int , uint8_t * );
static void bo_add_descr( bo_t *, uint8_t , uint32_t );

static void bo_fix_32be ( bo_t *, int , uint32_t );

static bo_t *box_new     ( char *fcc );
static bo_t *box_full_new( char *fcc, uint8_t v, uint32_t f );
static void  box_fix     ( bo_t *box );
static void  box_free    ( bo_t *box );
static void  box_gather  ( bo_t *box, bo_t *box2 );

static void box_send( sout_mux_t *p_mux,  bo_t *box );

static block_t *bo_to_sout( sout_instance_t *p_sout,  bo_t *box );

static bo_t *GetMoovBox( sout_mux_t *p_mux );

static block_t *ConvertSUBT( sout_mux_t *, mp4_stream_t *, block_t *);
static void ConvertAVC1( sout_mux_t *, mp4_stream_t *, block_t * );

/*****************************************************************************
 * Open:
 *****************************************************************************/
static int Open( vlc_object_t *p_this )
{
    sout_mux_t      *p_mux = (sout_mux_t*)p_this;
    sout_mux_sys_t  *p_sys;
    bo_t            *box;

    msg_Dbg( p_mux, "Mp4 muxer opend" );
    sout_CfgParse( p_mux, SOUT_CFG_PREFIX, ppsz_sout_options, p_mux->p_cfg );

    p_mux->pf_control   = Control;
    p_mux->pf_addstream = AddStream;
    p_mux->pf_delstream = DelStream;
    p_mux->pf_mux       = Mux;
    p_mux->p_sys        = p_sys = malloc( sizeof( sout_mux_sys_t ) );
    p_sys->i_pos        = 0;
    p_sys->i_nb_streams = 0;
    p_sys->pp_streams   = NULL;
    p_sys->i_mdat_pos   = 0;
    p_sys->b_mov        = p_mux->psz_mux && !strcmp( p_mux->psz_mux, "mov" );
    p_sys->b_3gp        = p_mux->psz_mux && !strcmp( p_mux->psz_mux, "3gp" );
    p_sys->i_dts_start  = 0;


    if( !p_sys->b_mov )
    {
        /* Now add ftyp header */
        box = box_new( "ftyp" );
        if( p_sys->b_3gp ) bo_add_fourcc( box, "3gp4" );
        else bo_add_fourcc( box, "isom" );
        bo_add_32be  ( box, 0 );
        if( p_sys->b_3gp ) bo_add_fourcc( box, "3gp4" );
        else bo_add_fourcc( box, "mp41" );
        box_fix( box );

        p_sys->i_pos += box->i_buffer;
        p_sys->i_mdat_pos = p_sys->i_pos;

        box_send( p_mux, box );
    }

    /* FIXME FIXME
     * Quicktime actually doesn't like the 64 bits extensions !!! */
    p_sys->b_64_ext = VLC_FALSE;

    /* Now add mdat header */
    box = box_new( "mdat" );
    bo_add_64be  ( box, 0 ); // enough to store an extended size

    p_sys->i_pos += box->i_buffer;

    box_send( p_mux, box );

    return VLC_SUCCESS;
}

/*****************************************************************************
 * Close:
 *****************************************************************************/
static void Close( vlc_object_t * p_this )
{
    sout_mux_t      *p_mux = (sout_mux_t*)p_this;
    sout_mux_sys_t  *p_sys = p_mux->p_sys;
    block_t   *p_hdr;
    bo_t            bo, *moov;
    vlc_value_t     val;

    int             i_trak;
    uint64_t        i_moov_pos;

    msg_Dbg( p_mux, "Close" );

    /* Update mdat size */
    bo_init( &bo, 0, NULL, VLC_TRUE );
    if( p_sys->i_pos - p_sys->i_mdat_pos >= (((uint64_t)1)<<32) )
    {
        /* Extended size */
        bo_add_32be  ( &bo, 1 );
        bo_add_fourcc( &bo, "mdat" );
        bo_add_64be  ( &bo, p_sys->i_pos - p_sys->i_mdat_pos );
    }
    else
    {
        bo_add_32be  ( &bo, 8 );
        bo_add_fourcc( &bo, "wide" );
        bo_add_32be  ( &bo, p_sys->i_pos - p_sys->i_mdat_pos - 8 );
        bo_add_fourcc( &bo, "mdat" );
    }
    p_hdr = bo_to_sout( p_mux->p_sout, &bo );
    free( bo.p_buffer );

    sout_AccessOutSeek( p_mux->p_access, p_sys->i_mdat_pos );
    sout_AccessOutWrite( p_mux->p_access, p_hdr );

    /* Create MOOV header */
    i_moov_pos = p_sys->i_pos;
    moov = GetMoovBox( p_mux );

    /* Check we need to create "fast start" files */
    var_Get( p_this, SOUT_CFG_PREFIX "faststart", &val );
    p_sys->b_fast_start = val.b_bool;
    while( p_sys->b_fast_start )
    {
        /* Move data to the end of the file so we can fit the moov header
         * at the start */
        block_t *p_buf;
        int64_t i_chunk, i_size = p_sys->i_pos - p_sys->i_mdat_pos;
        int i_moov_size = moov->i_buffer;

        while( i_size > 0 )
        {
            i_chunk = __MIN( 32768, i_size );
            p_buf = block_New( p_mux, i_chunk );
            sout_AccessOutSeek( p_mux->p_access,
                                p_sys->i_mdat_pos + i_size - i_chunk );
            if( sout_AccessOutRead( p_mux->p_access, p_buf ) < i_chunk )
            {
                msg_Warn( p_this, "read() not supported by access output, "
                          "won't create a fast start file" );
                p_sys->b_fast_start = VLC_FALSE;
                block_Release( p_buf );
                break;
            }
            sout_AccessOutSeek( p_mux->p_access, p_sys->i_mdat_pos + i_size +
                                i_moov_size - i_chunk );
            sout_AccessOutWrite( p_mux->p_access, p_buf );
            i_size -= i_chunk;
        }

        if( !p_sys->b_fast_start ) break;

        /* Fix-up samples to chunks table in MOOV header */
        for( i_trak = 0; i_trak < p_sys->i_nb_streams; i_trak++ )
        {
            mp4_stream_t *p_stream = p_sys->pp_streams[i_trak];
            unsigned int i;
            int i_chunk;

            moov->i_buffer = p_stream->i_stco_pos;
            for( i_chunk = 0, i = 0; i < p_stream->i_entry_count; i_chunk++ )
            {
                if( p_stream->b_stco64 )
                    bo_add_64be( moov, p_stream->entry[i].i_pos + i_moov_size);
                else
                    bo_add_32be( moov, p_stream->entry[i].i_pos + i_moov_size);

                while( i < p_stream->i_entry_count )
                {
                    if( i + 1 < p_stream->i_entry_count &&
                        p_stream->entry[i].i_pos + p_stream->entry[i].i_size
                        != p_stream->entry[i + 1].i_pos )
                    {
                        i++;
                        break;
                    }

                    i++;
                }
            }
        }

        moov->i_buffer = i_moov_size;
        i_moov_pos = p_sys->i_mdat_pos;
        p_sys->b_fast_start = VLC_FALSE;
    }

    /* Write MOOV header */
    sout_AccessOutSeek( p_mux->p_access, i_moov_pos );
    box_send( p_mux, moov );

    /* Clean-up */
    for( i_trak = 0; i_trak < p_sys->i_nb_streams; i_trak++ )
    {
        mp4_stream_t *p_stream = p_sys->pp_streams[i_trak];

        es_format_Clean( &p_stream->fmt );
        if( p_stream->avc.i_sps ) free( p_stream->avc.sps );
        if( p_stream->avc.i_pps ) free( p_stream->avc.pps );
        free( p_stream->entry );
        free( p_stream );
    }
    if( p_sys->i_nb_streams ) free( p_sys->pp_streams );
    free( p_sys );
}

/*****************************************************************************
 * Control:
 *****************************************************************************/
static int Control( sout_mux_t *p_mux, int i_query, va_list args )
{
    vlc_bool_t *pb_bool;

   switch( i_query )
   {
       case MUX_CAN_ADD_STREAM_WHILE_MUXING:
           pb_bool = (vlc_bool_t*)va_arg( args, vlc_bool_t * );
           *pb_bool = VLC_FALSE;
           return VLC_SUCCESS;

       case MUX_GET_ADD_STREAM_WAIT:
           pb_bool = (vlc_bool_t*)va_arg( args, vlc_bool_t * );
           *pb_bool = VLC_TRUE;
           return VLC_SUCCESS;

       case MUX_GET_MIME:   /* Not needed, as not streamable */
        default:
            return VLC_EGENERIC;
   }
}

/*****************************************************************************
 * AddStream:
 *****************************************************************************/
static int AddStream( sout_mux_t *p_mux, sout_input_t *p_input )
{
    sout_mux_sys_t  *p_sys = p_mux->p_sys;
    mp4_stream_t    *p_stream;

    switch( p_input->p_fmt->i_codec )
    {
        case VLC_FOURCC( 'm', 'p', '4', 'a' ):
        case VLC_FOURCC( 'm', 'p', '4', 'v' ):
        case VLC_FOURCC( 'm', 'p', 'g', 'a' ):
        case VLC_FOURCC( 'm', 'p', 'g', 'v' ):
        case VLC_FOURCC( 'M', 'J', 'P', 'G' ):
        case VLC_FOURCC( 'm', 'j', 'p', 'b' ):
        case VLC_FOURCC( 'S', 'V', 'Q', '1' ):
        case VLC_FOURCC( 'S', 'V', 'Q', '3' ):
        case VLC_FOURCC( 'H', '2', '6', '3' ):
        case VLC_FOURCC( 'h', '2', '6', '4' ):
        case VLC_FOURCC( 's', 'a', 'm', 'r' ):
        case VLC_FOURCC( 's', 'a', 'w', 'b' ):
            break;
        case VLC_FOURCC( 's', 'u', 'b', 't' ):
            msg_Warn( p_mux, "subtitle track added like in .mov (even when creating .mp4)" );
            break;
        default:
            msg_Err( p_mux, "unsupported codec %4.4s in mp4",
                     (char*)&p_input->p_fmt->i_codec );
            return VLC_EGENERIC;
    }