rawdv.c

VLC Player Source Code

/*****************************************************************************
 * rawdv.c : raw DV input module for vlc
 *****************************************************************************
 * Copyright (C) 2001-2007 the VideoLAN team
 * $Id$
 *
 * Authors: Gildas Bazin <[e-mail]>
 *          Paul Corke <paul dot corke at datatote dot co dot uk>
 *
 * 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>

/*****************************************************************************
 * Module descriptor
 *****************************************************************************/
#define HURRYUP_TEXT N_( "Hurry up" )
#define HURRYUP_LONGTEXT N_( "The demuxer will advance timestamps if the " \
                "input can't keep up with the rate." )

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

vlc_module_begin();
    set_shortname( "DV" );
    set_description( N_("DV (Digital Video) demuxer") );
    set_capability( "demux", 3 );
    set_category( CAT_INPUT );
    set_subcategory( SUBCAT_INPUT_DEMUX );
    add_bool( "rawdv-hurry-up", 0, NULL, HURRYUP_TEXT, HURRYUP_LONGTEXT, false );
    set_callbacks( Open, Close );
    add_shortcut( "rawdv" );
vlc_module_end();


/*****************************************************************************
 A little bit of background information (copied over from libdv glossary).

 - DIF block: A block of 80 bytes. This is the basic data framing unit of the
       DVC tape format, analogous to sectors of hard disc.

 - Video Section: Each DIF sequence contains a video section, consisting of
       135 DIF blocks, which are further subdivided into Video Segments.

 - Video Segment: A video segment consists of 5 DIF blocks, each corresponding
       to a single compressed macroblock.

*****************************************************************************/


/*****************************************************************************
 * Constants
 *****************************************************************************/
#define DV_PAL_FRAME_SIZE  144000
#define DV_NTSC_FRAME_SIZE 122000

/*****************************************************************************
 * Definitions of structures used by this plugin
 *****************************************************************************/
typedef struct {
    int8_t sct;      /* Section type (header,subcode,aux,audio,video) */
    int8_t dsn;      /* DIF sequence number (0-12) */
    int    fsc;      /* First (0)/Second channel (1) */
    int8_t dbn;      /* DIF block number (0-134) */
} dv_id_t;

typedef struct {
    int    dsf;      /* DIF sequence flag: 525/60 (0) or 625,50 (1) */
    int8_t apt;
    int    tf1;
    int8_t ap1;
    int    tf2;
    int8_t ap2;
    int    tf3;
    int8_t ap3;
} dv_header_t;

struct demux_sys_t
{
    int    frame_size;

    es_out_id_t *p_es_video;
    es_format_t  fmt_video;

    es_out_id_t *p_es_audio;
    es_format_t  fmt_audio;

    int    i_dsf;
    double f_rate;
    int    i_bitrate;

    /* program clock reference (in units of 90kHz) */
    mtime_t i_pcr;
    bool b_hurry_up;
};

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

static block_t *dv_extract_audio( demux_t *p_demux,
                                  block_t* p_frame_block );

/*****************************************************************************
 * Open: initializes raw DV demux 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, *p_peek_backup;

    uint32_t    i_dword;
    dv_header_t dv_header;
    dv_id_t     dv_id;

    /* It isn't easy to recognize a raw DV stream. The chances that we'll
     * mistake a stream from another type for a raw DV stream are too high, so
     * we'll rely on the file extension to trigger this demux. Alternatively,
     * it is possible to force this demux. */

    /* Check for DV file extension */
    if( !demux_IsPathExtension( p_demux, ".dv" ) && !p_demux->b_force )
        return VLC_EGENERIC;

    if( stream_Peek( p_demux->s, &p_peek, DV_PAL_FRAME_SIZE ) <
        DV_NTSC_FRAME_SIZE )
    {
        /* Stream too short ... */
        msg_Err( p_demux, "cannot peek()" );
        return VLC_EGENERIC;
    }
    p_peek_backup = p_peek;

    /* fill in the dv_id_t structure */
    i_dword = GetDWBE( p_peek ); p_peek += 4;
    dv_id.sct = i_dword >> (32 - 3);
    i_dword <<= 8;
    dv_id.dsn = i_dword >> (32 - 4);
    i_dword <<= 4;
    dv_id.fsc = i_dword >> (32 - 1);
    i_dword <<= 4;
    dv_id.dbn = i_dword >> (32 - 8);
    i_dword <<= 8;

    if( dv_id.sct != 0 )
    {
        msg_Warn( p_demux, "not a raw DV stream header" );
        return VLC_EGENERIC;
    }

    /* fill in the dv_header_t structure */
    dv_header.dsf = i_dword >> (32 - 1);
    i_dword <<= 1;
    if( i_dword >> (32 - 1) ) /* incorrect bit */
    {
        msg_Warn( p_demux, "incorrect bit" );
        return VLC_EGENERIC;
    }

    i_dword = GetDWBE( p_peek ); p_peek += 4;
    i_dword <<= 5;
    dv_header.apt = i_dword >> (32 - 3);
    i_dword <<= 3;
    dv_header.tf1 = i_dword >> (32 - 1);
    i_dword <<= 5;
    dv_header.ap1 = i_dword >> (32 - 3);
    i_dword <<= 3;
    dv_header.tf2 = i_dword >> (32 - 1);
    i_dword <<= 5;
    dv_header.ap2 = i_dword >> (32 - 3);
    i_dword <<= 3;
    dv_header.tf3 = i_dword >> (32 - 1);
    i_dword <<= 5;
    dv_header.ap3 = i_dword >> (32 - 3);

    p_peek += 72;                                  /* skip rest of DIF block */

    /* Set p_input field */
    p_demux->pf_demux   = Demux;
    p_demux->pf_control = Control;
    p_demux->p_sys      = p_sys = malloc( sizeof( demux_sys_t ) );
    if( !p_sys )
        return VLC_ENOMEM;

    p_sys->b_hurry_up = var_CreateGetBool( p_demux, "rawdv-hurry-up" );
    msg_Dbg( p_demux, "Realtime DV Source: %s", (p_sys->b_hurry_up)?"Yes":"No" );

    p_sys->i_dsf = dv_header.dsf;
    p_sys->frame_size = dv_header.dsf ? 12 * 150 * 80 : 10 * 150 * 80;
    p_sys->f_rate = dv_header.dsf ? 25 : 29.97;

    p_sys->i_pcr = 1;
    p_sys->p_es_video = NULL;
    p_sys->p_es_audio = NULL;

    p_sys->i_bitrate = 0;

    es_format_Init( &p_sys->fmt_video, VIDEO_ES, VLC_FOURCC('d','v','s','d') );
    p_sys->fmt_video.video.i_width = 720;
    p_sys->fmt_video.video.i_height= dv_header.dsf ? 576 : 480;;

    /* FIXME FIXME */
#if 0
    /* necessary because input_SplitBuffer() will only get
     * INPUT_DEFAULT_BUFSIZE bytes at a time. */
    p_input->i_bufsize = p_sys->frame_size;
#endif

    p_sys->p_es_video = es_out_Add( p_demux->out, &p_sys->fmt_video );

    /* Audio stuff */
    p_peek = p_peek_backup + 80*6+80*16*3 + 3; /* beginning of AAUX pack */
    if( *p_peek == 0x50 )
    {
        es_format_Init( &p_sys->fmt_audio, AUDIO_ES,
                        VLC_FOURCC('a','r','a','w') );

        p_sys->fmt_audio.audio.i_channels = 2;
        switch( (p_peek[4] >> 3) & 0x07 )
        {
        case 0: