nsv.c

video linux conference

/*****************************************************************************
 * nsv.c: NullSoft Video demuxer.
 *****************************************************************************
 * Copyright (C) 2004 VideoLAN
 * $Id: nsv.c 10547 2005-04-04 23:50:07Z hartman $
 *
 * Authors: 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., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
 *****************************************************************************/

/*****************************************************************************
 * Preamble
 *****************************************************************************/
#include <stdlib.h>                                      /* malloc(), free() */

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

/* TODO:
 *  - implement NSVf parsing (to get meta data)
 *  - implement missing Control (and in the right way)
 *  - ...
 */

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

vlc_module_begin();
    set_description( _("NullSoft demuxer" ) );
    set_capability( "demux2", 10 );
    set_category( CAT_INPUT );
    set_subcategory( SUBCAT_INPUT_DEMUX );
    set_callbacks( Open, Close );
    add_shortcut( "nsv" );
vlc_module_end();

/*****************************************************************************
 * Local prototypes
 *****************************************************************************/

struct demux_sys_t
{
    es_format_t  fmt_audio;
    es_out_id_t *p_audio;

    es_format_t  fmt_video;
    es_out_id_t *p_video;

    es_format_t  fmt_sub;
    es_out_id_t  *p_sub;

    int64_t     i_pcr;
    int64_t     i_time;
    int64_t     i_pcr_inc;
};

static int Demux  ( demux_t *p_demux );
static int Control( demux_t *p_demux, int i_query, va_list args );

static int ReSynch( demux_t *p_demux );

static int ReadNSVf( demux_t *p_demux );
static int ReadNSVs( demux_t *p_demux );

/*****************************************************************************
 * Open
 *****************************************************************************/
static int Open( vlc_object_t *p_this )
{
    demux_t     *p_demux = (demux_t*)p_this;
    demux_sys_t *p_sys;

    uint8_t     *p_peek;

    if( stream_Peek( p_demux->s, &p_peek, 8 ) < 8 ) return VLC_EGENERIC;

    if( strncmp( p_peek, "NSVf", 4 ) && strncmp( p_peek, "NSVs", 4 ))
    {
       /* In case we had force this demuxer we try to resynch */
        if( strcmp( p_demux->psz_demux, "nsv" ) || ReSynch( p_demux ) )
        {
            return VLC_EGENERIC;
        }
    }

    /* Fill p_demux field */
    p_demux->pf_demux = Demux;
    p_demux->pf_control = Control;
    p_demux->p_sys = p_sys = malloc( sizeof( demux_sys_t ) );

    es_format_Init( &p_sys->fmt_audio, AUDIO_ES, 0 );
    p_sys->p_audio = NULL;

    es_format_Init( &p_sys->fmt_video, VIDEO_ES, 0 );
    p_sys->p_video = NULL;

    es_format_Init( &p_sys->fmt_sub, SPU_ES, 0 );
    p_sys->p_sub = NULL;

    p_sys->i_pcr   = 1;
    p_sys->i_time  = 0;
    p_sys->i_pcr_inc = 0;

    return VLC_SUCCESS;
}

/*****************************************************************************
 * Close
 *****************************************************************************/
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;

    free( p_sys );
}


/*****************************************************************************
 * Demux:
 *****************************************************************************/
static int Demux( demux_t *p_demux )
{
    demux_sys_t *p_sys = p_demux->p_sys;

    uint8_t     header[5];
    uint8_t     *p_peek;

    int         i_size;
    block_t     *p_frame;

    for( ;; )
    {
        if( stream_Peek( p_demux->s, &p_peek, 8 ) < 8 )
        {
            msg_Warn( p_demux, "cannot peek" );
            return 0;
        }

        if( !strncmp( p_peek, "NSVf", 4 ) )
        {
            if( ReadNSVf( p_demux ) )
            {
                return -1;
            }
        }
        else if( !strncmp( p_peek, "NSVs", 4 ) )
        {
            if( ReadNSVs( p_demux ) )
            {
                return -1;
            }
            break;
        }
        else if( GetWLE( p_peek ) == 0xbeef )
        {
            /* Next frame of the current NSVs chunk */
            if( stream_Read( p_demux->s, NULL, 2 ) < 2 )
            {
                msg_Warn( p_demux, "cannot read" );
                return 0;
            }
            break;
        }
        else
        {
            msg_Err( p_demux, "invalid signature 0x%x (%4.4s)", *(uint32_t*)p_peek, (char*)p_peek );
            if( ReSynch( p_demux ) )
            {
                return -1;
            }
        }
    }

    if( stream_Read( p_demux->s, header, 5 ) < 5 )
    {
        msg_Warn( p_demux, "cannot read" );
        return 0;
    }

    /* Set PCR */
    es_out_Control( p_demux->out, ES_OUT_SET_PCR, (int64_t)p_sys->i_pcr );

    /* Read video */
    i_size = ( header[0] >> 4 ) | ( header[1] << 4 ) | ( header[2] << 12 );
    if( i_size > 0 )
    {
        /* extra data ? */
        if( (header[0]&0x0f) != 0x0 )
        {
            uint8_t      aux[6];
            int          i_aux;
            vlc_fourcc_t fcc;
            if( stream_Read( p_demux->s, aux, 6 ) < 6 )
            {
                msg_Warn( p_demux, "cannot read" );
                return 0;
            }
            i_aux = GetWLE( aux );
            fcc   = VLC_FOURCC( aux[2], aux[3], aux[4], aux[5] );

            msg_Dbg( p_demux, "Belekas: %d - size=%d fcc=%4.4s",
                     header[0]&0xf, i_aux, (char*)&fcc );

            if( fcc == VLC_FOURCC( 'S', 'U', 'B', 'T' ) && i_aux > 2 )
            {
                if( p_sys->p_sub == NULL )
                {
                    p_sys->fmt_sub.i_codec = VLC_FOURCC( 's', 'u', 'b', 't' );
                    p_sys->p_sub = es_out_Add( p_demux->out, &p_sys->fmt_sub );
                    es_out_Control( p_demux->out, ES_OUT_SET_ES, p_sys->p_sub );
                }
                stream_Read( p_demux->s, NULL, 2 );

                if( ( p_frame = stream_Block( p_demux->s, i_aux - 2 ) ) )
                {
                    uint8_t *p = p_frame->p_buffer;

                    while( p < &p_frame->p_buffer[p_frame->i_buffer] && *p != 0 )
                    {
                        p++;
                    }
                    if( *p == 0 && p + 1 < &p_frame->p_buffer[p_frame->i_buffer] )
                    {
                        p_frame->i_buffer -= p + 1 - p_frame->p_buffer;
                        p_frame->p_buffer = p + 1;
                    }

                    /* Skip the first part (it is the language name) */
                    p_frame->i_pts = p_sys->i_pcr;
                    p_frame->i_dts = p_sys->i_pcr + 4000000;    /* 4s */

                    es_out_Send( p_demux->out, p_sys->p_sub, p_frame );
                }
            }
            else
            {
                /* We skip this extra data */
                if( stream_Read( p_demux->s, NULL, i_aux ) < i_aux )
                {
                    msg_Warn( p_demux, "cannot read" );
                    return 0;
                }
            }
            i_size -= 6 + i_aux;
        }

        /* msg_Dbg( p_demux, "frame video size=%d", i_size ); */
        if( i_size > 0 && ( p_frame = stream_Block( p_demux->s, i_size ) ) )
        {
            p_frame->i_dts = p_sys->i_pcr;
            es_out_Send( p_demux->out, p_sys->p_video, p_frame );
        }
    }

    /* Read audio */
    i_size = header[3] | ( header[4] << 8 );
    if( i_size > 0 )
    {
        /* msg_Dbg( p_demux, "frame audio size=%d", i_size ); */