flac.c

VLC Player Source Code

/*****************************************************************************
 * flac.c : FLAC demux module for vlc
 *****************************************************************************
 * Copyright (C) 2001-2007 the VideoLAN team
 * $Id: 2459c9501895a536d2885edd7dc5869c7101f85b $
 *
 * Authors: Gildas Bazin <[e-mail]>
 *          Laurent Aimar <[e-mail]>
 *
 * 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
 *****************************************************************************/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#include <vlc_common.h>
#include <vlc_plugin.h>
#include <vlc_demux.h>
#include <vlc_meta.h>
#include <vlc_input.h>
#include <vlc_codec.h>
#include <assert.h>
#include <vlc_charset.h>

/*****************************************************************************
 * Module descriptor
 *****************************************************************************/
static int  Open  ( vlc_object_t * );
static void Close ( vlc_object_t * );

vlc_module_begin();
    set_description( N_("FLAC demuxer") );
    set_capability( "demux", 155 );
    set_category( CAT_INPUT );
    set_subcategory( SUBCAT_INPUT_DEMUX );
    set_callbacks( Open, Close );
    add_shortcut( "flac" );
vlc_module_end();

/*****************************************************************************
 * Local prototypes
 *****************************************************************************/
static int Demux  ( demux_t * );
static int Control( demux_t *, int, va_list );

static int  ReadMeta( demux_t *, uint8_t **pp_streaminfo, int *pi_streaminfo );

struct demux_sys_t
{
    bool  b_start;
    es_out_id_t *p_es;

    /* Packetizer */
    decoder_t *p_packetizer;

    vlc_meta_t *p_meta;
    audio_replay_gain_t replay_gain;

    int64_t i_time_offset;
    int64_t i_pts;
    int64_t i_pts_start;

    int64_t i_length; /* Length from stream info */
    int64_t i_data_pos;

    /* */
    int         i_seekpoint;
    seekpoint_t **seekpoint;

    /* */
    int                i_attachments;
    input_attachment_t **attachments;
    int                i_cover_idx;
    int                i_cover_score;
};

#define STREAMINFO_SIZE 38
#define FLAC_PACKET_SIZE 16384

/*****************************************************************************
 * Open: initializes ES structures
 *****************************************************************************/
static int Open( vlc_object_t * p_this )
{
    demux_t     *p_demux = (demux_t*)p_this;
    demux_sys_t *p_sys;
    const uint8_t *p_peek;
    uint8_t     *p_streaminfo;
    int         i_streaminfo;

    /* Have a peep at the show. */
    if( stream_Peek( p_demux->s, &p_peek, 4 ) < 4 ) return VLC_EGENERIC;

    if( p_peek[0]!='f' || p_peek[1]!='L' || p_peek[2]!='a' || p_peek[3]!='C' )
    {
        if( !p_demux->b_force ) return VLC_EGENERIC;

        /* User forced */
        msg_Err( p_demux, "this doesn't look like a flac stream, "
                 "continuing anyway" );
    }

    p_demux->pf_demux   = Demux;
    p_demux->pf_control = Control;
    p_demux->p_sys      = p_sys = malloc( sizeof( demux_sys_t ) );
    p_sys->b_start = true;
    p_sys->p_meta = NULL;
    memset( &p_sys->replay_gain, 0, sizeof(p_sys->replay_gain) );
    p_sys->i_length = 0;
    p_sys->i_time_offset = 0;
    p_sys->i_pts = 0;
    p_sys->i_pts_start = 0;
    p_sys->p_es = NULL;
    TAB_INIT( p_sys->i_seekpoint, p_sys->seekpoint );
    TAB_INIT( p_sys->i_attachments, p_sys->attachments);
    p_sys->i_cover_idx = 0;
    p_sys->i_cover_score = 0;

    /* We need to read and store the STREAMINFO metadata */
    if( ReadMeta( p_demux, &p_streaminfo, &i_streaminfo ) )
    {
        free( p_sys );
        return VLC_EGENERIC;
    }

    /* Load the FLAC packetizer */
    INIT_APACKETIZER( p_sys->p_packetizer, 'f', 'l', 'a', 'c' );

    /* Store STREAMINFO for the decoder and packetizer */
    p_streaminfo[4] |= 0x80; /* Fake this as the last metadata block */
    p_sys->p_packetizer->fmt_in.i_extra = i_streaminfo;
    p_sys->p_packetizer->fmt_in.p_extra = p_streaminfo;

    p_sys->p_packetizer->p_module =
        module_Need( p_sys->p_packetizer, "packetizer", NULL, 0 );
    if( !p_sys->p_packetizer->p_module )
    {
        free( p_sys->p_packetizer->fmt_in.p_extra );
        vlc_object_release( p_sys->p_packetizer );

        msg_Err( p_demux, "cannot find flac packetizer" );
        return VLC_EGENERIC;
    }

    if( p_sys->i_cover_idx < p_sys->i_attachments )
    {
        char psz_url[128];
        if( !p_sys->p_meta )
            p_sys->p_meta = vlc_meta_New();
        snprintf( psz_url, sizeof(psz_url), "attachment://%s",
                  p_sys->attachments[p_sys->i_cover_idx]->psz_name );
        vlc_meta_Set( p_sys->p_meta, vlc_meta_ArtworkURL, psz_url );
    }
    vlc_audio_replay_gain_MergeFromMeta( &p_sys->replay_gain, p_sys->p_meta );
    return VLC_SUCCESS;
}

/*****************************************************************************
 * Close: frees unused data
 *****************************************************************************/
static void Close( vlc_object_t * p_this )
{
    demux_t     *p_demux = (demux_t*)p_this;
    demux_sys_t *p_sys = p_demux->p_sys;

    TAB_CLEAN( p_sys->i_seekpoint, p_sys->seekpoint );

    int i;
    for( i = 0; i < p_sys->i_attachments; i++ )
        free( p_sys->attachments[i] );
    TAB_CLEAN( p_sys->i_attachments, p_sys->attachments);

    /* Unneed module */
    module_Unneed( p_sys->p_packetizer, p_sys->p_packetizer->p_module );

    free( p_sys->p_packetizer->fmt_in.p_extra );

    /* Delete the decoder */
    vlc_object_release( p_sys->p_packetizer );
    if( p_sys->p_meta )
        vlc_meta_Delete( p_sys->p_meta );
    free( p_sys );
}

/*****************************************************************************
 * Demux: reads and demuxes data packets
 *****************************************************************************
 * Returns -1 in case of error, 0 in case of EOF, 1 otherwise
 *****************************************************************************/
static int Demux( demux_t *p_demux )
{
    demux_sys_t *p_sys = p_demux->p_sys;
    block_t     *p_block_in, *p_block_out;

    if( !( p_block_in = stream_Block( p_demux->s, FLAC_PACKET_SIZE ) ) )
        return 0;

    p_block_in->i_pts = p_block_in->i_dts = p_sys->b_start ? 1 : 0;
    p_sys->b_start = false;

    while( (p_block_out = p_sys->p_packetizer->pf_packetize(
                p_sys->p_packetizer, &p_block_in )) )
    {
        while( p_block_out )
        {
            block_t *p_next = p_block_out->p_next;

            p_block_out->p_next = NULL;

            if( p_sys->p_es == NULL )
            {
                p_sys->p_packetizer->fmt_out.b_packetized = true;
                p_sys->p_packetizer->fmt_out.audio_replay_gain = p_sys->replay_gain;
                p_sys->p_es = es_out_Add( p_demux->out, &p_sys->p_packetizer->fmt_out);
            }

            p_sys->i_pts = p_block_out->i_dts;

            /* Correct timestamp */
            p_block_out->i_pts += p_sys->i_time_offset;
            p_block_out->i_dts += p_sys->i_time_offset;

            /* set PCR */
            if( p_block_out->i_dts >= p_sys->i_pts_start + p_sys->i_time_offset )
                es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_block_out->i_dts );
            else
                es_out_Control( p_demux->out, ES_OUT_RESET_PCR );

            es_out_Send( p_demux->out, p_sys->p_es, p_block_out );

            p_block_out = p_next;
        }
    }
    return 1;
}

/*****************************************************************************
 * Control:
 *****************************************************************************/
static int64_t ControlGetLength( demux_t *p_demux )
{
    demux_sys_t *p_sys = p_demux->p_sys;
    const int64_t i_size = stream_Size(p_demux->s) - p_sys->i_data_pos;
    int64_t i_length = p_sys->i_length;
    int i;

    /* Try to fix length using seekpoint and current size for truncated file */
    for( i = p_sys->i_seekpoint-1; i >= 0; i-- )
    {
        seekpoint_t *s = p_sys->seekpoint[i];
        if( s->i_byte_offset <= i_size )
        {
            if( i+1 < p_sys->i_seekpoint )
            {
                /* Broken file */
                seekpoint_t *n = p_sys->seekpoint[i+1];
                assert( n->i_byte_offset != s->i_byte_offset); /* Should be ensured by ParseSeekTable */
                i_length = s->i_time_offset + (n->i_time_offset-s->i_time_offset) * (i_size-s->i_byte_offset) / (n->i_byte_offset-s->i_byte_offset);
            }
            break;
        }
    }
    return i_length;
}

static int64_t ControlGetTime( demux_t *p_demux )
{
    demux_sys_t *p_sys = p_demux->p_sys;
    return __MAX(p_sys->i_pts, p_sys->i_pts_start) + p_sys->i_time_offset;
}

static int ControlSetTime( demux_t *p_demux, int64_t i_time )
{
    demux_sys_t *p_sys = p_demux->p_sys;
    int64_t i_delta_time;
    bool b_seekable;
    int i;

    /* */
    stream_Control( p_demux->s, STREAM_CAN_SEEK, &b_seekable );
    if( !b_seekable )
        return VLC_EGENERIC;

    /* */
    assert( p_sys->i_seekpoint > 0 );   /* ReadMeta ensure at least (0,0) */
    for( i = p_sys->i_seekpoint-1; i >= 0; i-- )
    {
        if( p_sys->seekpoint[i]->i_time_offset <= i_time )
            break;
    }
    i_delta_time = i_time - p_sys->seekpoint[i]->i_time_offset;

    /* XXX We do exact seek if it's not too far away(45s) */
    if( i_delta_time < 45*INT64_C(1000000) )
    {
        if( stream_Seek( p_demux->s, p_sys->seekpoint[i]->i_byte_offset+p_sys->i_data_pos ) )
            return VLC_EGENERIC;

        p_sys->i_time_offset = p_sys->seekpoint[i]->i_time_offset - p_sys->i_pts;
        p_sys->i_pts_start = p_sys->i_pts+i_delta_time;
        es_out_Control( p_demux->out, ES_OUT_SET_NEXT_DISPLAY_TIME, p_sys->p_es, p_sys->i_pts_start + p_sys->i_time_offset );
    }
    else
    {
        int64_t i_delta_offset;
        int64_t i_next_time;
        int64_t i_next_offset;

        if( i+1 < p_sys->i_seekpoint )
        {
            i_next_time   = p_sys->seekpoint[i+1]->i_time_offset;
            i_next_offset = p_sys->seekpoint[i+1]->i_byte_offset;
        }
        else
        {
            i_next_time   = p_sys->i_length;
            i_next_offset = stream_Size(p_demux->s)-p_sys->i_data_pos;
        }

        i_delta_offset = 0;
        if( i_next_time-p_sys->seekpoint[i]->i_time_offset > 0 )
            i_delta_offset = (i_next_offset - p_sys->seekpoint[i]->i_byte_offset) * i_delta_time /
                             (i_next_time-p_sys->seekpoint[i]->i_time_offset);

        if( stream_Seek( p_demux->s, p_sys->seekpoint[i]->i_byte_offset+p_sys->i_data_pos + i_delta_offset ) )
            return VLC_EGENERIC;

        p_sys->i_pts_start = p_sys->i_pts;
        p_sys->i_time_offset = (p_sys->seekpoint[i]->i_time_offset+i_delta_time) - p_sys->i_pts;
    }
    return VLC_SUCCESS;
}

static int Control( demux_t *p_demux, int i_query, va_list args )
{
    demux_sys_t *p_sys = p_demux->p_sys;

    if( i_query == DEMUX_GET_META )
    {
        vlc_meta_t *p_meta = (vlc_meta_t *)va_arg( args, vlc_meta_t* );
        if( p_demux->p_sys->p_meta )
            vlc_meta_Merge( p_meta, p_demux->p_sys->p_meta );
        return VLC_SUCCESS;
    }
    else if( i_query == DEMUX_HAS_UNSUPPORTED_META )
    {
        bool *pb_bool = (bool*)va_arg( args, bool* );
        *pb_bool = true;
        return VLC_SUCCESS;
    }