frame.c

VLC Player Source Code

                if (macroblock_modes & MACROBLOCK_MOTION_FORWARD)
                    bs_write( bs, (macroblock_modes & MOTION_TYPE_MASK) / MOTION_TYPE_BASE, 2);
                break;
            }
            else if (tr->frame_pred_frame_dct) break;
            else
            {
                if (macroblock_modes & MACROBLOCK_MOTION_FORWARD)
                    bs_write( bs, (macroblock_modes & MOTION_TYPE_MASK) / MOTION_TYPE_BASE, 2);
                if (macroblock_modes & (MACROBLOCK_INTRA | MACROBLOCK_PATTERN))
                    bs_write( bs, macroblock_modes & DCT_TYPE_INTERLACED ? 1 : 0, 1);
                break;
            }

        case B_TYPE:
            if (tr->picture_structure != FRAME_PICTURE)
            {
                if (! (macroblock_modes & MACROBLOCK_INTRA))
                    bs_write( bs, (macroblock_modes & MOTION_TYPE_MASK) / MOTION_TYPE_BASE, 2);
                break;
            }
            else if (tr->frame_pred_frame_dct) break;
            else
            {
                if (macroblock_modes & MACROBLOCK_INTRA) goto intra;
                bs_write( bs, (macroblock_modes & MOTION_TYPE_MASK) / MOTION_TYPE_BASE, 2);
                if (macroblock_modes & (MACROBLOCK_INTRA | MACROBLOCK_PATTERN))
                {
                    intra:
                    bs_write( bs, macroblock_modes & DCT_TYPE_INTERLACED ? 1 : 0, 1);
                }
                break;
            }
    }
}

static const uint8_t map_non_linear_mquant[113] =
{
    0,1,2,3,4,5,6,7,8,8,9,9,10,10,11,11,12,12,13,13,14,14,15,15,16,16,
    16,17,17,17,18,18,18,18,19,19,19,19,20,20,20,20,21,21,21,21,22,22,
    22,22,23,23,23,23,24,24,24,24,24,24,24,25,25,25,25,25,25,25,26,26,
    26,26,26,26,26,26,27,27,27,27,27,27,27,27,28,28,28,28,28,28,28,29,
    29,29,29,29,29,29,29,29,29,30,30,30,30,30,30,30,31,31,31,31,31
};
static inline void put_quantiser( transrate_t *tr )
{
    bs_transrate_t *bs = &tr->bs;

    bs_write( bs, tr->q_scale_type ? map_non_linear_mquant[tr->new_quantizer_scale] : tr->new_quantizer_scale >> 1, 5 );
    tr->last_coded_scale = tr->new_quantizer_scale;
}

/* generate variable length code for macroblock_address_increment (6.3.16) */
static inline void putaddrinc( transrate_t *tr, int addrinc )
{
    bs_transrate_t *bs = &tr->bs;

    while ( addrinc >= 33 )
    {
        bs_write( bs, 0x08, 11 ); /* macroblock_escape */
        addrinc -= 33;
    }

    bs_write( bs, addrinctab[addrinc].code, addrinctab[addrinc].len );
}

static int slice_init( transrate_t *tr,  int code )
{
    bs_transrate_t *bs = &tr->bs;
    int offset;
    const MBAtab * mba;

    tr->v_offset = (code - 1) * 16;

    tr->quantizer_scale = get_quantizer_scale( tr );
    if ( tr->new_quantizer_scale < tr->quantizer_scale )
        tr->new_quantizer_scale = scale_quant( tr, tr->qrate );

    /*LOGF("************************\nstart of slice %i in %s picture. ori quant: %i new quant: %i\n", code,
        (picture_coding_type == I_TYPE ? "I_TYPE" : (picture_coding_type == P_TYPE ? "P_TYPE" : "B_TYPE")),
        quantizer_scale, new_quantizer_scale);*/

    /* ignore intra_slice and all the extra data */
    while (bs->i_bit_in_cache & 0x80000000)
    {
        bs_flush( bs, 9 );
    }

    /* decode initial macroblock address increment */
    offset = 0;
    for( ;; )
    {
        if (bs->i_bit_in_cache >= 0x08000000)
        {
            mba = MBA_5 + (UBITS (bs->i_bit_in_cache, 6) - 2);
            break;
        }
        else if (bs->i_bit_in_cache >= 0x01800000)
        {
            mba = MBA_11 + (UBITS (bs->i_bit_in_cache, 12) - 24);
            break;
        }
        else if( UBITS (bs->i_bit_in_cache, 12 ) == 8 )
        {
            /* macroblock_escape */
            offset += 33;
            bs_flush(bs, 11);
        }
        else
        {
            return -1;
        }
    }

    bs_flush(bs, mba->len + 1);
    tr->h_offset = (offset + mba->mba) << 4;

    while( tr->h_offset - (int)tr->horizontal_size_value >= 0)
    {
        tr->h_offset -= tr->horizontal_size_value;
        tr->v_offset += 16;
    }

    if( tr->v_offset > tr->vertical_size_value - 16 )
    {
        return -1;
    }
    return (offset + mba->mba);
}

static void mpeg2_slice( transrate_t *tr, const int code )
{
    bs_transrate_t *bs = &tr->bs;
    int mba_inc;
    int first_in_slice = 1;

    if( (mba_inc = slice_init( tr, code )) < 0 )
    {
        return;
    }

    for( ;; )
    {
        const MBAtab * mba;
        int macroblock_modes;
        int mba_local;
        int i;

        while (unlikely(bs->i_bit_in < 24)) bs_refill( bs );

        macroblock_modes = get_macroblock_modes( tr );
        if (macroblock_modes & MACROBLOCK_QUANT)
            tr->quantizer_scale = get_quantizer_scale( tr );
        if (tr->new_quantizer_scale < tr->quantizer_scale)
            tr->new_quantizer_scale = scale_quant( tr, tr->qrate );

        //LOGF("blk %i : ", h_offset >> 4);

        if (macroblock_modes & MACROBLOCK_INTRA)
        {
            RunLevel block[6][65]; // terminated by level = 0, so we need 64+1
            RunLevel new_block[6][65]; // terminated by level = 0, so we need 64+1
            uint32_t dc[6];
            uint8_t  dc_len[6];

            // begin saving data
            int batb;
            uint8_t   p_n_ow[32], *p_n_w,
                    *p_o_ow = bs->p_ow, *p_o_w = bs->p_w;
            uint32_t  i_n_bit_out, i_n_bit_out_cache,
                    i_o_bit_out  = bs->i_bit_out, i_o_bit_out_cache = bs->i_bit_out_cache;

            bs->i_bit_out_cache = 0; bs->i_bit_out = BITS_IN_BUF;
            bs->p_ow = bs->p_w = p_n_ow;

            //LOG("intra "); if (macroblock_modes & MACROBLOCK_QUANT) LOGF("got new quant: %i ", quantizer_scale);

            if (tr->concealment_motion_vectors)
            {
                if (tr->picture_structure != FRAME_PICTURE)
                {
                    bs_copy(bs, 1); /* remove field_select */
                }
                /* like motion_frame, but parsing without actual motion compensation */
                get_motion_delta(bs, tr->f_code[0][0]);
                get_motion_delta(bs, tr->f_code[0][1]);

                bs_copy(bs, 1); /* remove marker_bit */
            }

            assert(bs->p_w - bs->p_ow < 32);

            p_n_w = bs->p_w;
            i_n_bit_out = bs->i_bit_out;
            i_n_bit_out_cache = bs->i_bit_out_cache;
            assert(bs->p_ow == p_n_ow);

            bs->i_bit_out = i_o_bit_out ;
            bs->i_bit_out_cache = i_o_bit_out_cache;
            bs->p_ow = p_o_ow;
            bs->p_w = p_o_w;
            // end saving data

            if( tr->intra_vlc_format )
            {
                /* Luma */
                for ( i = 0; i < 4; i++ )
                {
                    get_luma_dc_dct_diff( bs, dc + i, dc_len + i );
                    get_intra_block_B15( tr, block[i] );
                    if (tr->b_error) return;
                }
                /* Chroma */
                for ( ; i < 6; i++ )
                {
                    get_chroma_dc_dct_diff( bs, dc + i, dc_len + i );
                    get_intra_block_B15( tr, block[i] );
                    if (tr->b_error) return;
                }
            }
            else
            {
                /* Luma */
                for ( i = 0; i < 4; i++ )
                {
                    get_luma_dc_dct_diff( bs, dc + i, dc_len + i );
                    get_intra_block_B14( tr, block[i] );
                    if (tr->b_error) return;
                }
                /* Chroma */
                for ( ; i < 6; i++ )
                {
                    get_chroma_dc_dct_diff( bs, dc + i, dc_len + i );
                    get_intra_block_B14( tr, block[i] );
                    if (tr->b_error) return;
                }
            }

            transrate_mb( tr, block, new_block, 0x3f, 1 );

            if (tr->last_coded_scale == tr->new_quantizer_scale)
                macroblock_modes &= ~MACROBLOCK_QUANT;

            if ( first_in_slice )
            {
                put_quantiser( tr );
                bs_write( bs, 0, 1 );
                macroblock_modes &= ~MACROBLOCK_QUANT;
            }
            putaddrinc( tr, mba_inc );
            mba_inc = 0;
            putmbdata( tr, macroblock_modes );
            if( macroblock_modes & MACROBLOCK_QUANT )
            {
                put_quantiser( tr );
            }

            // put saved motion data...
            for (batb = 0; batb < (p_n_w - p_n_ow); batb++)
            {
                bs_write( bs, p_n_ow[batb], 8 );
            }
            bs_write( bs, i_n_bit_out_cache, BITS_IN_BUF - i_n_bit_out );
            // end saved motion data...

            for ( i = 0; i < 6; i++ )
            {
                bs_write( bs, *(dc + i), *(dc_len + i) );
                putintrablk( bs, new_block[i], tr->intra_vlc_format );
            }
 
        }
        else
        {
            RunLevel block[6][65]; // terminated by level = 0, so we need 64+1
            RunLevel new_block[6][65]; // terminated by level = 0, so we need 64+1
            int new_coded_block_pattern = 0;
            int cbp = 0;

            // begin saving data
            int batb;
            uint8_t   p_n_ow[32], *p_n_w,
                    *p_o_ow = bs->p_ow, *p_o_w = bs->p_w;
            uint32_t  i_n_bit_out, i_n_bit_out_cache,
                    i_o_bit_out  = bs->i_bit_out, i_o_bit_out_cache = bs->i_bit_out_cache;

            bs->i_bit_out_cache = 0; bs->i_bit_out = BITS_IN_BUF;
            bs->p_ow = bs->p_w = p_n_ow;

            if (tr->picture_structure == FRAME_PICTURE)
                switch (macroblock_modes & MOTION_TYPE_MASK)
                {
                    case MC_FRAME: MOTION_CALL (motion_fr_frame, macroblock_modes); break;
                    case MC_FIELD: MOTION_CALL (motion_fr_field, macroblock_modes); break;
                    case MC_DMV: MOTION_CALL (motion_fr_dmv, MACROBLOCK_MOTION_FORWARD); break;
                }
            else
                switch (macroblock_modes & MOTION_TYPE_MASK)
                {
                    case MC_FIELD: MOTION_CALL (motion_fi_field, macroblock_modes); break;
                    case MC_16X8: MOTION_CALL (motion_fi_16x8, macroblock_modes); break;
                    case MC_DMV: MOTION_CALL (motion_fi_dmv, MACROBLOCK_MOTION_FORWARD); break;
                }

            //LOG("non intra "); if (macroblock_modes & MACROBLOCK_QUANT) LOGF("got new quant: %i ", quantizer_scale);

            if (macroblock_modes & MACROBLOCK_PATTERN)
            {
                int last_in_slice;

                cbp = get_coded_block_pattern( bs );

                for ( i = 0; i < 6; i++ )
                {
                    if ( cbp & (1 << (5 - i)) )
                    {
                        get_non_intra_block( tr, block[i] );
                        if (tr->b_error) return;
                    }
                }
                last_in_slice = !UBITS( bs->i_bit_in_cache, 11 );

                new_coded_block_pattern = transrate_mb( tr, block, new_block,
                                                        cbp, 0 );

                if ( !new_coded_block_pattern &&
                        !(macroblock_modes
                            & (MACROBLOCK_MOTION_FORWARD
                                | MACROBLOCK_MOTION_BACKWARD))
                        && (first_in_slice || last_in_slice) )
                {
                    /* First mb in slice, just code a 0-mv mb.
                     * This is wrong for last in slice, but it only shows
                     * a few artefacts. */
                    macroblock_modes |= MACROBLOCK_MOTION_FORWARD;
                    if (tr->picture_structure == FRAME_PICTURE)
                    {
                        macroblock_modes |= MC_FRAME;
                        bs_write( bs, 0x3, 2 ); /* motion vectors */
                    }
                    else
                    {
                        macroblock_modes |= MC_FIELD;
                        bs_write( bs,
                             (tr->picture_structure == BOTTOM_FIELD ? 1 : 0),
                             1); /* motion field select */
                        bs_write( bs, 0x3, 2 ); /* motion vectors */
                    }
                }

                if ( !new_coded_block_pattern )
                {
                    macroblock_modes &= ~MACROBLOCK_PATTERN;
                    macroblock_modes &= ~MACROBLOCK_QUANT;
                }
                else
                {
                    if ( tr->last_coded_scale == tr->new_quantizer_scale )
                    {
                        macroblock_modes &= ~MACROBLOCK_QUANT;
                    }
                    else
                    {
                        macroblock_modes |= MACROBLOCK_QUANT;
                    }
                }
            }

            assert(bs->p_w - bs->p_ow < 32);

            p_n_w = bs->p_w;
            i_n_bit_out = bs->i_bit_out;
            i_n_bit_out_cache = bs->i_bit_out_cache;
            assert(bs->p_ow == p_n_ow);

            bs->i_bit_out = i_o_bit_out ;
            bs->i_bit_out_cache = i_o_bit_out_cache;
            bs->p_ow = p_o_ow;
            bs->p_w = p_o_w;
            // end saving data

            if ( macroblock_modes &
                    (MACROBLOCK_MOTION_FORWARD | MACROBLOCK_MOTION_BACKWARD
                      | MACROBLOCK_PATTERN) )
            {
                if ( first_in_slice )
                {
                    put_quantiser( tr );
                    bs_write( bs, 0, 1 );
                    macroblock_modes &= ~MACROBLOCK_QUANT;
                }
                putaddrinc( tr, mba_inc );
                mba_inc = 0;
                putmbdata( tr, macroblock_modes );
                if ( macroblock_modes & MACROBLOCK_QUANT )
                {
                    put_quantiser( tr );
                }

                // put saved motion data...
                for (batb = 0; batb < (p_n_w - p_n_ow); batb++)
                {
                    bs_write( bs, p_n_ow[batb], 8 );
                }
                bs_write( bs, i_n_bit_out_cache, BITS_IN_BUF - i_n_bit_out);
                // end saved motion data...

                if (macroblock_modes & MACROBLOCK_PATTERN)
                {
                    /* Write CBP */
                    bs_write( bs, cbptable[new_coded_block_pattern].code,
                              cbptable[new_coded_block_pattern].len );

                    for ( i = 0; i < 6; i++ )
                    {
                        if ( new_coded_block_pattern & (1 << (5 - i)) )
                        {
                            putnonintrablk( bs, new_block[i] );
                        }
                    }
                }
            }
            else
            {
                /* skipped macroblock */
                mba_inc++;
            }
        }

        if (bs->p_c > bs->p_r || bs->p_w > bs->p_rw)
        {
            tr->b_error = 1;
            return;
        }
        //LOGF("\n\to: %i c: %i n: %i\n", quantizer_scale, last_coded_scale, new_quantizer_scale);

        NEXT_MACROBLOCK;

        first_in_slice = 0;
        mba_local = 0;
        for ( ; ; )
        {
            if ( bs->i_bit_in_cache >= 0x10000000 )
            {
                mba = MBA_5 + (UBITS (bs->i_bit_in_cache, 5) - 2);
                break;
            }
            else if ( bs->i_bit_in_cache >= 0x03000000 )
            {
                mba = MBA_11 + (UBITS (bs->i_bit_in_cache, 11) - 24);
                break;
            }