dvbsub.c

uclinux 下的vlc播放器源代码

                break;
            }
        }

#if DEBUG_DVBSUB
        msg_Dbg( p_enc, "best palette has %d colors", p_fmt->p_palette->i_entries );
#endif

#ifndef RANDOM_DITHERING
        pi_delta = malloc( ( p_region->picture.p[0].i_pitch + 1 )
                            * sizeof(int) * 4  );
        for( i = 0; i < (p_region->picture.p[0].i_pitch + 1) * 4 ; i++ )
        {
            pi_delta[ i ] = 0;
        }
#endif

        /* Fill image with our new colours */
        for( p = 0; p < p_region->picture.p[0].i_visible_lines ; p++ )
        {
            int i_ydelta = 0, i_udelta = 0, i_vdelta = 0, i_adelta = 0;

            for( n = 0; n < p_region->picture.p[0].i_pitch ; n++ )
            {
                int i_offset = p * p_region->picture.p[0].i_pitch + n;
                int y, u, v, a;
                int i_mindist, i_best;

                y = (int)p_region->picture.p[0].p_pixels[i_offset];
                u = (int)p_region->picture.p[1].p_pixels[i_offset];
                v = (int)p_region->picture.p[2].p_pixels[i_offset];
                a = (int)p_region->picture.p[3].p_pixels[i_offset];

                /* Add dithering compensation */
#ifdef RANDOM_DITHERING
                y += ((i_seed & 0xff) - 0x80) * i_tolerance / 0x80;
                u += (((i_seed >> 8) & 0xff) - 0x80) * i_tolerance / 0x80;
                v += (((i_seed >> 16) & 0xff) - 0x80) * i_tolerance / 0x80;
                a += (((i_seed >> 24) & 0xff) - 0x80) * i_tolerance / 0x80;
#else
                y += i_ydelta + pi_delta[ n * 4 ];
                u += i_udelta + pi_delta[ n * 4 + 1 ];
                v += i_vdelta + pi_delta[ n * 4 + 2 ];
                a += i_adelta + pi_delta[ n * 4 + 3 ];
#endif

                /* Find best colour in palette */
                for( i_mindist = 99999999, i_best = 0, j = 0; j < p_fmt->p_palette->i_entries; j++ )
                {
                    int i_dist = 0;

                    i_dist += abs((int)p_fmt->p_palette->palette[j][0] - y);
                    i_dist += abs((int)p_fmt->p_palette->palette[j][1] - u);
                    i_dist += abs((int)p_fmt->p_palette->palette[j][2] - v);
                    i_dist += 2 * abs((int)p_fmt->p_palette->palette[j][3] - a);

                    if( i_dist < i_mindist )
                    {
                        i_mindist = i_dist;
                        i_best = j;
                    }
                }

                /* Set pixel to best color */
                p_region->picture.p[0].p_pixels[i_offset] = i_best;

                /* Update dithering state */
#ifdef RANDOM_DITHERING
                i_seed = (i_seed * 0x1283837) ^ 0x789479 ^ (i_seed >> 13);
#else
                i_ydelta = y - (int)p_fmt->p_palette->palette[i_best][0];
                i_udelta = u - (int)p_fmt->p_palette->palette[i_best][1];
                i_vdelta = v - (int)p_fmt->p_palette->palette[i_best][2];
                i_adelta = a - (int)p_fmt->p_palette->palette[i_best][3];
                pi_delta[ n * 4 ] = i_ydelta * 3 / 8;
                pi_delta[ n * 4 + 1 ] = i_udelta * 3 / 8;
                pi_delta[ n * 4 + 2 ] = i_vdelta * 3 / 8;
                pi_delta[ n * 4 + 3 ] = i_adelta * 3 / 8;
                i_ydelta = i_ydelta * 5 / 8;
                i_udelta = i_udelta * 5 / 8;
                i_vdelta = i_vdelta * 5 / 8;
                i_adelta = i_adelta * 5 / 8;
#endif
            }
        }
#ifndef RANDOM_DITHERING
        free( pi_delta );
#endif

        /* pad palette */
        for( i = p_fmt->p_palette->i_entries; i < i_max_entries; i++ )
        {
            p_fmt->p_palette->palette[i][0] = 0;
            p_fmt->p_palette->palette[i][1] = 0;
            p_fmt->p_palette->palette[i][2] = 0;
            p_fmt->p_palette->palette[i][3] = 0;
        }
        p_fmt->p_palette->i_entries = i_max_entries;
#if DEBUG_DVBSUB
        msg_Dbg( p_enc, "best palette has %d colors", p_fmt->p_palette->i_entries );
#endif
    }
    return p_subpic;
} /* End of hack */

/****************************************************************************
 * Encode: the whole thing
 ****************************************************************************/
static block_t *Encode( encoder_t *p_enc, subpicture_t *p_subpic )
{
    subpicture_t *p_temp = NULL;
    subpicture_region_t *p_region = NULL;
    bs_t bits, *s = &bits;
    block_t *p_block;

    if( !p_subpic || !p_subpic->p_region ) return NULL;

    /* FIXME: this is a hack to convert VLC_FOURCC('Y','U','V','A') into
     *  VLC_FOURCC('Y','U','V','P')
     */
    p_region = p_subpic->p_region;
    if( p_region->fmt.i_chroma == VLC_FOURCC('Y','U','V','A') )
    {
        p_temp = YuvaYuvp( p_enc, p_subpic );
        if( !p_temp )
        {
            msg_Err( p_enc, "no picture in subpicture" );
            return NULL;
        }
        p_region = p_subpic->p_region;
    }

    /* Sanity check */
    if( !p_region ) return NULL;

    if( p_region->fmt.i_chroma != VLC_FOURCC('T','E','X','T') &&
        p_region->fmt.i_chroma != VLC_FOURCC('Y','U','V','P') ) return NULL;

    if( p_region->fmt.p_palette )
    {
        switch( p_region->fmt.p_palette->i_entries )
        {
            case 0:
            case 4:
            case 16:
            case 256:
                break;
            default:
                msg_Err( p_enc, "subpicture palette (%d) not handled",
                            p_region->fmt.p_palette->i_entries );
                return NULL;
        }
    }
    /* End of hack */

#if DEBUG_DVBSUB
    msg_Dbg( p_enc, "encoding subpicture" );
#endif
    p_block = block_New( p_enc, 64000 );
    bs_init( s, p_block->p_buffer, p_block->i_buffer );

    bs_write( s, 8, 0x20 ); /* Data identifier */
    bs_write( s, 8, 0x0 );  /* Subtitle stream id */

    encode_page_composition( p_enc, s, p_subpic );
    encode_region_composition( p_enc, s, p_subpic );
    encode_clut( p_enc, s, p_subpic );
    encode_object( p_enc, s, p_subpic );

    /* End of display */
    bs_write( s, 8, 0x0f ); /* Sync byte */
    bs_write( s, 8, DVBSUB_ST_ENDOFDISPLAY ); /* Segment type */
    bs_write( s, 16, 1 );  /* Page id */
    bs_write( s, 16, 0 );  /* Segment length */

    bs_write( s, 8, 0xff );/* End marker */
    p_block->i_buffer = bs_pos( s ) / 8;
    p_block->i_pts = p_block->i_dts = p_subpic->i_start;
    if( !p_subpic->b_ephemer && p_subpic->i_stop > p_subpic->i_start )
    {
        block_t *p_block_stop;

        p_block->i_length = p_subpic->i_stop - p_subpic->i_start;

        /* Send another (empty) subtitle to signal the end of display */
        p_block_stop = block_New( p_enc, 64000 );
        bs_init( s, p_block_stop->p_buffer, p_block_stop->i_buffer );
        bs_write( s, 8, 0x20 ); /* Data identifier */
        bs_write( s, 8, 0x0 );  /* Subtitle stream id */
        encode_page_composition( p_enc, s, 0 );
        bs_write( s, 8, 0x0f ); /* Sync byte */
        bs_write( s, 8, DVBSUB_ST_ENDOFDISPLAY ); /* Segment type */
        bs_write( s, 16, 1 );  /* Page id */
        bs_write( s, 16, 0 );  /* Segment length */
        bs_write( s, 8, 0xff );/* End marker */
        p_block_stop->i_buffer = bs_pos( s ) / 8;
        p_block_stop->i_pts = p_block_stop->i_dts = p_subpic->i_stop;
        block_ChainAppend( &p_block, p_block_stop );
        p_block_stop->i_length = 100000; /* p_subpic->i_stop - p_subpic->i_start; */
    }
#ifdef DEBUG_DVBSUB
    msg_Dbg( p_enc, "subpicture encoded properly" );
#endif
    return p_block;
}

/*****************************************************************************
 * CloseEncoder: encoder destruction
 *****************************************************************************/
static void CloseEncoder( vlc_object_t *p_this )
{
    encoder_t *p_enc = (encoder_t *)p_this;
    encoder_sys_t *p_sys = p_enc->p_sys;

    var_Destroy( p_this , ENC_CFG_PREFIX "x" );
    var_Destroy( p_this , ENC_CFG_PREFIX "y" );
    var_Destroy( p_this , ENC_CFG_PREFIX "timeout" );

    if( p_sys->i_regions ) free( p_sys->p_regions );
    free( p_sys );
}

static void encode_page_composition( encoder_t *p_enc, bs_t *s,
                                     subpicture_t *p_subpic )
{
    encoder_sys_t *p_sys = p_enc->p_sys;
    subpicture_region_t *p_region;
    vlc_bool_t b_mode_change = VLC_FALSE;
    int i_regions, i_timeout;

    bs_write( s, 8, 0x0f ); /* Sync byte */
    bs_write( s, 8, DVBSUB_ST_PAGE_COMPOSITION ); /* Segment type */
    bs_write( s, 16, 1 ); /* Page id */

    for( i_regions = 0, p_region = p_subpic ? p_subpic->p_region : 0;
         p_region; p_region = p_region->p_next, i_regions++ )
    {
        if( i_regions >= p_sys->i_regions )
        {
            encoder_region_t region;
            region.i_width = region.i_height = 0;
            p_sys->p_regions =
                realloc( p_sys->p_regions, sizeof(encoder_region_t) *
                         (p_sys->i_regions + 1) );
            p_sys->p_regions[p_sys->i_regions++] = region;
        }

        if( ( p_sys->p_regions[i_regions].i_width <
              (int)p_region->fmt.i_visible_width ) || 
            ( p_sys->p_regions[i_regions].i_width >
              (int)p_region->fmt.i_visible_width ) )
        {
            b_mode_change = VLC_TRUE;
            msg_Dbg( p_enc, "region %i width change: %i -> %i",
                     i_regions, p_sys->p_regions[i_regions].i_width,
                     p_region->fmt.i_visible_width );
            p_sys->p_regions[i_regions].i_width =
                p_region->fmt.i_visible_width;
        }
        if( p_sys->p_regions[i_regions].i_height <
             (int)p_region->fmt.i_visible_height )
        {
            b_mode_change = VLC_TRUE;
            msg_Dbg( p_enc, "region %i height change: %i -> %i",
                     i_regions, p_sys->p_regions[i_regions].i_height,
                     p_region->fmt.i_visible_height );
            p_sys->p_regions[i_regions].i_height =
                p_region->fmt.i_visible_height;
        }
    }

    bs_write( s, 16, i_regions * 6 + 2 ); /* Segment length */

    i_timeout = 0;
    if( p_subpic && !p_subpic->b_ephemer &&
        p_subpic->i_stop > p_subpic->i_start )
    {
        i_timeout = (p_subpic->i_stop - p_subpic->i_start) / 1000000;
    }

    bs_write( s, 8, i_timeout ); /* Timeout */
    bs_write( s, 4, p_sys->i_page_ver++ );
    bs_write( s, 2, b_mode_change ?
              DVBSUB_PCS_STATE_CHANGE : DVBSUB_PCS_STATE_ACQUISITION );
    bs_write( s, 2, 0 ); /* Reserved */

    for( i_regions = 0, p_region = p_subpic ? p_subpic->p_region : 0;
         p_region; p_region = p_region->p_next, i_regions++ )
    {
        bs_write( s, 8, i_regions );
        bs_write( s, 8, 0 ); /* Reserved */
        if( (p_sys->i_offset_x > 0) && (p_sys->i_offset_y > 0) )
        {
            bs_write( s, 16, p_sys->i_offset_x ); /* override x position */
            bs_write( s, 16, p_sys->i_offset_y ); /* override y position */
        }
        else
        {
            bs_write( s, 16, p_subpic->i_x + p_region->i_x );
            bs_write( s, 16, p_subpic->i_y + p_region->i_y );
        }
    }
}

static void encode_clut( encoder_t *p_enc, bs_t *s, subpicture_t *p_subpic )
{
    encoder_sys_t *p_sys = p_enc->p_sys;
    subpicture_region_t *p_region = p_subpic->p_region;
    video_palette_t *p_pal, pal;
    int i;

    /* Sanity check */
    if( !p_region ) return;

    if( p_region->fmt.i_chroma == VLC_FOURCC('Y','U','V','P') )
    {
        p_pal = p_region->fmt.p_palette;
    }
    else
    {
        pal.i_entries = 4;
        for( i = 0; i < 4; i++ )
        {
            pal.palette[i][0] = 0;
            pal.palette[i][1] = 0;
            pal.palette[i][2] = 0;
            pal.palette[i][3] = 0;
        }
        p_pal = &pal;
    }

    bs_write( s, 8, 0x0f ); /* Sync byte */
    bs_write( s, 8, DVBSUB_ST_CLUT_DEFINITION ); /* Segment type */
    bs_write( s, 16, 1 );  /* Page id */

    bs_write( s, 16, p_pal->i_entries * 6 + 2 ); /* Segment length */
    bs_write( s, 8, 1 ); /* Clut id */
    bs_write( s, 4, p_sys->i_clut_ver++ );
    bs_write( s, 4, 0 ); /* Reserved */

    for( i = 0; i < p_pal->i_entries; i++ )
    {
        bs_write( s, 8, i ); /* Clut entry id */
        bs_write( s, 1, p_pal->i_entries == 4 );   /* 2bit/entry flag */
        bs_write( s, 1, p_pal->i_entries == 16 );  /* 4bit/entry flag */
        bs_write( s, 1, p_pal->i_entries == 256 ); /* 8bit/entry flag */
        bs_write( s, 4, 0 ); /* Reserved */
        bs_write( s, 1, 1 ); /* Full range flag */
        bs_write( s, 8, p_pal->palette[i][3] ?  /* Y value */
                  (p_pal->palette[i][0] ? p_pal->palette[i][0] : 16) : 0 );
        bs_write( s, 8, p_pal->palette[i][1] ); /* Cr value */
        bs_write( s, 8, p_pal->palette[i][2] ); /* Cb value */
        bs_write( s, 8, 0xff - p_pal->palette[i][3] ); /* T value */
    }
}

static void encode_region_composition( encoder_t *p_enc, bs_t *s,
                                       subpicture_t *p_subpic )
{
    encoder_sys_t *p_sys = p_enc->p_sys;
    subpicture_region_t *p_region;
    int i_region;

    for( i_region = 0, p_region = p_subpic->p_region; p_region;
         p_region = p_region->p_next, i_region++ )
    {
        int i_entries = 4, i_depth = 0x1, i_bg = 0;
        vlc_bool_t b_text =
            p_region->fmt.i_chroma == VLC_FOURCC('T','E','X','T');

        if( !b_text )
        {
            video_palette_t *p_pal = p_region->fmt.p_palette;

            if( !p_pal )
            {
                msg_Err( p_enc, "subpicture has no palette - ignoring it" );
                break;
            }

            i_entries = p_pal->i_entries;
            i_depth = i_entries == 4 ? 0x1 : i_entries == 16 ? 0x2 : 0x3;

            for( i_bg = 0; i_bg < p_pal->i_entries; i_bg++ )
            {
                if( !p_pal->palette[i_bg][3] ) break;
            }
        }

        bs_write( s, 8, 0x0f ); /* Sync byte */
        bs_write( s, 8, DVBSUB_ST_REGION_COMPOSITION ); /* Segment type */
        bs_write( s, 16, 1 );   /* Page id */

        bs_write( s, 16, 10 + 6 + (b_text ? 2 : 0) ); /* Segment length */
        bs_write( s, 8, i_region );
        bs_write( s, 4, p_sys->i_region_ver++ );

        /* Region attributes */
        bs_write( s, 1, i_bg < i_entries ); /* Fill */
        bs_write( s, 3, 0 ); /* Reserved */
        bs_write( s, 16, p_sys->p_regions[i_region].i_width );
        bs_write( s, 16, p_sys->p_regions[i_region].i_height );
        bs_write( s, 3, i_depth );  /* Region level of compatibility */
        bs_write( s, 3, i_depth  ); /* Region depth */
        bs_write( s, 2, 0 ); /* Reserved */
        bs_write( s, 8, 1 ); /* Clut id */
        bs_write( s, 8, i_bg ); /* region 8bit pixel code */
        bs_write( s, 4, i_bg ); /* region 4bit pixel code */
        bs_write( s, 2, i_bg ); /*