transcode.c

video linux conference

    if( id->p_encoder->fmt_out.i_codec == VLC_FOURCC( 'm','p','3',' ' ) )
        id->p_encoder->fmt_out.i_codec = VLC_FOURCC( 'm','p','g','a' );

    return VLC_SUCCESS;
}

static void transcode_audio_close( sout_stream_t *p_stream,
                                   sout_stream_id_t *id )
{
    int i;

    /* Close decoder */
    if( id->p_decoder->p_module )
        module_Unneed( id->p_decoder, id->p_decoder->p_module );
    id->p_decoder->p_module = 0;

    /* Close encoder */
    if( id->p_encoder->p_module )
        module_Unneed( id->p_encoder, id->p_encoder->p_module );
    id->p_encoder->p_module = 0;

    /* Close filters */
    for( i = 0; i < id->i_filter; i++ )
    {
        vlc_object_detach( id->pp_filter[i] );
        if( id->pp_filter[i]->p_module )
            module_Unneed( id->pp_filter[i], id->pp_filter[i]->p_module );
        vlc_object_destroy( id->pp_filter[i] );
    }
}

static int transcode_audio_process( sout_stream_t *p_stream,
                                    sout_stream_id_t *id,
                                    block_t *in, block_t **out )
{
    sout_stream_sys_t *p_sys = p_stream->p_sys;
    aout_buffer_t *p_audio_buf;
    block_t *p_block, *p_audio_block;
    int i;
    *out = NULL;

    while( (p_audio_buf = id->p_decoder->pf_decode_audio( id->p_decoder,
                                                          &in )) )
    {
        if( p_sys->b_master_sync )
        {
            mtime_t i_dts = date_Get( &id->interpolated_pts ) + 1;
            p_sys->i_master_drift = p_audio_buf->start_date - i_dts;
            date_Increment( &id->interpolated_pts, p_audio_buf->i_nb_samples );
            p_audio_buf->start_date -= p_sys->i_master_drift;
            p_audio_buf->end_date -= p_sys->i_master_drift;
        }

        p_audio_block = p_audio_buf->p_sys;
        p_audio_block->i_buffer = p_audio_buf->i_nb_bytes;
        p_audio_block->i_dts = p_audio_block->i_pts =
            p_audio_buf->start_date;
        p_audio_block->i_length = p_audio_buf->end_date -
            p_audio_buf->start_date;
        p_audio_block->i_samples = p_audio_buf->i_nb_samples;

        /* Run filter chain */
        for( i = 0; i < id->i_filter; i++ )
        {
            p_audio_block =
                id->pp_filter[i]->pf_audio_filter( id->pp_filter[i],
                                                   p_audio_block );
        }

        p_audio_buf->p_buffer = p_audio_block->p_buffer;
        p_audio_buf->i_nb_bytes = p_audio_block->i_buffer;
        p_audio_buf->i_nb_samples = p_audio_block->i_samples;
        p_audio_buf->start_date = p_audio_block->i_dts;
        p_audio_buf->end_date = p_audio_block->i_dts + p_audio_block->i_length;

        p_block = id->p_encoder->pf_encode_audio( id->p_encoder, p_audio_buf );
        block_ChainAppend( out, p_block );
        block_Release( p_audio_block );
        free( p_audio_buf );
    }

    return VLC_SUCCESS;
}

static void audio_release_buffer( aout_buffer_t *p_buffer )
{
    if( p_buffer && p_buffer->p_sys ) block_Release( p_buffer->p_sys );
    if( p_buffer ) free( p_buffer );
}

static aout_buffer_t *audio_new_buffer( decoder_t *p_dec, int i_samples )
{
    aout_buffer_t *p_buffer;
    block_t *p_block;
    int i_size;

    if( p_dec->fmt_out.audio.i_bitspersample )
    {
        i_size = i_samples * p_dec->fmt_out.audio.i_bitspersample / 8 *
            p_dec->fmt_out.audio.i_channels;
    }
    else if( p_dec->fmt_out.audio.i_bytes_per_frame &&
             p_dec->fmt_out.audio.i_frame_length )
    {
        i_size = i_samples * p_dec->fmt_out.audio.i_bytes_per_frame /
            p_dec->fmt_out.audio.i_frame_length;
    }
    else
    {
        i_size = i_samples * 4 * p_dec->fmt_out.audio.i_channels;
    }

    p_buffer = malloc( sizeof(aout_buffer_t) );
    p_buffer->pf_release = audio_release_buffer;
    p_buffer->p_sys = p_block = block_New( p_dec, i_size );

    p_buffer->p_buffer = p_block->p_buffer;
    p_buffer->i_size = p_buffer->i_nb_bytes = p_block->i_buffer;
    p_buffer->i_nb_samples = i_samples;
    p_block->i_samples = i_samples;

    return p_buffer;
}

static void audio_del_buffer( decoder_t *p_dec, aout_buffer_t *p_buffer )
{
    if( p_buffer && p_buffer->p_sys ) block_Release( p_buffer->p_sys );
    if( p_buffer ) free( p_buffer );
}

/*
 * video
 */
static int transcode_video_new( sout_stream_t *p_stream, sout_stream_id_t *id )
{
    sout_stream_sys_t *p_sys = p_stream->p_sys;
    int i;

    /*
     * Open decoder
     */

    /* Initialization of decoder structures */
    id->p_decoder->fmt_out = id->p_decoder->fmt_in;
    id->p_decoder->fmt_out.i_extra = 0;
    id->p_decoder->fmt_out.p_extra = 0;
    id->p_decoder->pf_decode_video = 0;
    id->p_decoder->pf_vout_buffer_new = video_new_buffer_decoder;
    id->p_decoder->pf_vout_buffer_del = video_del_buffer_decoder;
    id->p_decoder->pf_picture_link    = video_link_picture_decoder;
    id->p_decoder->pf_picture_unlink  = video_unlink_picture_decoder;
    id->p_decoder->p_owner = malloc( sizeof(decoder_owner_sys_t) );
    for( i = 0; i < PICTURE_RING_SIZE; i++ )
        id->p_decoder->p_owner->pp_pics[i] = 0;
    id->p_decoder->p_owner->p_sys = p_sys;
    //id->p_decoder->p_cfg = p_sys->p_video_cfg;

    id->p_decoder->p_module =
        module_Need( id->p_decoder, "decoder", "$codec", 0 );

    if( !id->p_decoder->p_module )
    {
        msg_Err( p_stream, "cannot find decoder" );
        return VLC_EGENERIC;
    }

    /*
     * Open encoder.
     * Because some info about the decoded input will only be available
     * once the first frame is decoded, we actually only test the availability
     * of the encoder here.
     */

    /* Initialization of encoder format structures */
    es_format_Init( &id->p_encoder->fmt_in, id->p_decoder->fmt_in.i_cat,
                    id->p_decoder->fmt_out.i_codec );
    id->p_encoder->fmt_in.video.i_chroma = id->p_decoder->fmt_out.i_codec;

    /* The dimensions will be set properly later on.
     * Just put sensible values so we can test an encoder is available. */
    id->p_encoder->fmt_in.video.i_width =
        id->p_encoder->fmt_out.video.i_width ?
        id->p_encoder->fmt_out.video.i_width :
        id->p_decoder->fmt_in.video.i_width ?
        id->p_decoder->fmt_in.video.i_width : 16;
    id->p_encoder->fmt_in.video.i_height =
        id->p_encoder->fmt_out.video.i_height ?
        id->p_encoder->fmt_out.video.i_height :
        id->p_decoder->fmt_in.video.i_height ?
        id->p_decoder->fmt_in.video.i_height : 16;
    id->p_encoder->fmt_in.video.i_frame_rate = 25;
    id->p_encoder->fmt_in.video.i_frame_rate_base = 1;

    id->p_encoder->i_threads = p_sys->i_threads;
    id->p_encoder->p_cfg = p_sys->p_video_cfg;

    id->p_encoder->p_module =
        module_Need( id->p_encoder, "encoder", p_sys->psz_venc, VLC_TRUE );
    if( !id->p_encoder->p_module )
    {
        msg_Err( p_stream, "cannot find encoder" );
        module_Unneed( id->p_decoder, id->p_decoder->p_module );
        id->p_decoder->p_module = 0;
        return VLC_EGENERIC;
    }

    /* Close the encoder.
     * We'll open it only when we have the first frame. */
    module_Unneed( id->p_encoder, id->p_encoder->p_module );
    id->p_encoder->p_module = NULL;

    if( p_sys->i_threads >= 1 )
    {
        p_sys->id_video = id;
        vlc_mutex_init( p_stream, &p_sys->lock_out );
        vlc_cond_init( p_stream, &p_sys->cond );
        memset( p_sys->pp_pics, 0, sizeof(p_sys->pp_pics) );
        p_sys->i_first_pic = 0;
        p_sys->i_last_pic = 0;
        p_sys->p_buffers = NULL;
        p_sys->b_die = p_sys->b_error = 0;
        if( vlc_thread_create( p_sys, "encoder", EncoderThread,
                               VLC_THREAD_PRIORITY_VIDEO, VLC_FALSE ) )
        {
            msg_Err( p_stream, "cannot spawn encoder thread" );
            module_Unneed( id->p_decoder, id->p_decoder->p_module );
            id->p_decoder->p_module = 0;
            return VLC_EGENERIC;
        }
    }

    date_Set( &id->interpolated_pts, 0 );

    return VLC_SUCCESS;
}

static int transcode_video_encoder_open( sout_stream_t *p_stream,
                                         sout_stream_id_t *id )
{
    sout_stream_sys_t *p_sys = p_stream->p_sys;

    /* Hack because of the copy packetizer which can fail to detect the
     * proper size (which forces us to wait until the 1st frame
     * is decoded) */
    int i_width = id->p_decoder->fmt_out.video.i_width -
        p_sys->i_crop_left - p_sys->i_crop_right;
    int i_height = id->p_decoder->fmt_out.video.i_height -
        p_sys->i_crop_top - p_sys->i_crop_bottom;

    if( id->p_encoder->fmt_out.video.i_width <= 0 &&
        id->p_encoder->fmt_out.video.i_height <= 0 && p_sys->f_scale )
    {
        /* Apply the scaling */
        id->p_encoder->fmt_out.video.i_width = i_width * p_sys->f_scale;
        id->p_encoder->fmt_out.video.i_height = i_height * p_sys->f_scale;
    }
    else if( id->p_encoder->fmt_out.video.i_width > 0 &&
             id->p_encoder->fmt_out.video.i_height <= 0 )
    {
        id->p_encoder->fmt_out.video.i_height =
            id->p_encoder->fmt_out.video.i_width / (double)i_width * i_height;
    }
    else if( id->p_encoder->fmt_out.video.i_width <= 0 &&
             id->p_encoder->fmt_out.video.i_height > 0 )
    {
        id->p_encoder->fmt_out.video.i_width =
            id->p_encoder->fmt_out.video.i_height / (double)i_height * i_width;
    }

    /* Make sure the size is at least a multiple of 2 */
    id->p_encoder->fmt_out.video.i_width =
        (id->p_encoder->fmt_out.video.i_width + 1) >> 1 << 1;
    id->p_encoder->fmt_out.video.i_height =
        (id->p_encoder->fmt_out.video.i_height + 1) >> 1 << 1;

    id->p_encoder->fmt_in.video.i_width =
        id->p_encoder->fmt_out.video.i_width;
    id->p_encoder->fmt_in.video.i_height =
        id->p_encoder->fmt_out.video.i_height;

    if( !id->p_encoder->fmt_out.video.i_frame_rate ||
        !id->p_encoder->fmt_out.video.i_frame_rate_base )
    {
        if( id->p_decoder->fmt_out.video.i_frame_rate &&
            id->p_decoder->fmt_out.video.i_frame_rate_base )
        {
            id->p_encoder->fmt_out.video.i_frame_rate =
                id->p_decoder->fmt_out.video.i_frame_rate;
            id->p_encoder->fmt_out.video.i_frame_rate_base =
                id->p_decoder->fmt_out.video.i_frame_rate_base;
        }
        else
        {
            /* Pick a sensible default value */
            id->p_encoder->fmt_out.video.i_frame_rate = 25;
            id->p_encoder->fmt_out.video.i_frame_rate_base = 1;
        }
    }

    id->p_encoder->fmt_in.video.i_frame_rate =
        id->p_encoder->fmt_out.video.i_frame_rate;
    id->p_encoder->fmt_in.video.i_frame_rate_base =
        id->p_encoder->fmt_out.video.i_frame_rate_base;

    date_Init( &id->interpolated_pts,
               id->p_encoder->fmt_out.video.i_frame_rate,
               id->p_encoder->fmt_out.video.i_frame_rate_base );

    /* Check whether a particular aspect ratio was requested */
    if( !id->p_encoder->fmt_out.video.i_aspect )
    {
        id->p_encoder->fmt_out.video.i_aspect =
            id->p_decoder->fmt_out.video.i_aspect;
    }
    id->p_encoder->fmt_in.video.i_aspect =
        id->p_encoder->fmt_out.video.i_aspect;

    id->p_encoder->p_module =
        module_Need( id->p_encoder, "encoder", p_sys->psz_venc, VLC_TRUE );
    if( !id->p_encoder->p_module )
    {
        msg_Err( p_stream, "cannot find encoder" );
        return VLC_EGENERIC;
    }

    id->p_encoder->fmt_in.video.i_chroma = id->p_encoder->fmt_in.i_codec;

    /* Hack for mp2v/mp1v transcoding support */
    if( id->p_encoder->fmt_out.i_codec == VLC_FOURCC('m','p','1','v') ||
        id->p_encoder->fmt_out.i_codec == VLC_FOURCC('m','p','2','v') )
    {
        id->p_encoder->fmt_out.i_codec = VLC_FOURCC('m','p','g','v');
    }

    id->id = p_stream->p_sys->p_out->pf_add( p_stream->p_sys->p_out,
                                             &id->p_encoder->fmt_out );
    if( !id->id )
    {
        msg_Err( p_stream, "cannot add this stream" );
        return VLC_EGENERIC;
    }

    return VLC_SUCCESS;
}

static void transcode_video_close( sout_stream_t *p_stream,
                                   sout_stream_id_t *id )
{
    int i, j;

    if( p_stream->p_sys->i_threads >= 1 )
    {
        vlc_mutex_lock( &p_stream->p_sys->lock_out );
        p_stream->p_sys->b_die = 1;
        vlc_cond_signal( &p_stream->p_sys->cond );
        vlc_mutex_unlock( &p_stream->p_sys->lock_out );
        vlc_thread_join( p_stream->p_sys );
        vlc_mutex_destroy( &p_stream->p_sys->lock_out );
        vlc_cond_destroy( &p_stream->p_sys->cond );
    }

    /* Close decoder */
    if( id->p_decoder->p_module )
        module_Unneed( id->p_decoder, id->p_decoder->p_module );

    if( id->p_decoder->p_owner )
    {
        /* Clean-up pictures ring buffer */
        for( i = 0; i < PICTURE_RING_SIZE; i++ )
        {
            if( id->p_decoder->p_owner->pp_pics[i] )
                video_del_buffer( VLC_OBJECT(id->p_decoder),
                                  id->p_decoder->p_owner->pp_pics[i] );
        }
        free( id->p_decoder->p_owner );
    }