cavlc.c

X264的纯C语言的的原码

        return;
    }
    else if( i_mb_type == I_4x4 || i_mb_type == I_8x8 )
    {
        int di = i_mb_type == I_8x8 ? 4 : 1;
        bs_write_ue( s, i_mb_i_offset + 0 );
        if( h->pps->b_transform_8x8_mode )
            bs_write1( s, h->mb.b_transform_8x8 );

        /* Prediction: Luma */
        for( i = 0; i < 16; i += di )
        {
            int i_pred = x264_mb_predict_intra4x4_mode( h, i );
            int i_mode = x264_mb_pred_mode4x4_fix( h->mb.cache.intra4x4_pred_mode[x264_scan8[i]] );

            if( i_pred == i_mode)
            {
                bs_write1( s, 1 );  /* b_prev_intra4x4_pred_mode */
            }
            else
            {
                bs_write1( s, 0 );  /* b_prev_intra4x4_pred_mode */
                if( i_mode < i_pred )
                {
                    bs_write( s, 3, i_mode );
                }
                else
                {
                    bs_write( s, 3, i_mode - 1 );
                }
            }
        }
        bs_write_ue( s, x264_mb_pred_mode8x8c_fix[ h->mb.i_chroma_pred_mode ] );
    }
    else if( i_mb_type == I_16x16 )
    {
        bs_write_ue( s, i_mb_i_offset + 1 + x264_mb_pred_mode16x16_fix[h->mb.i_intra16x16_pred_mode] +
                        h->mb.i_cbp_chroma * 4 + ( h->mb.i_cbp_luma == 0 ? 0 : 12 ) );
        bs_write_ue( s, x264_mb_pred_mode8x8c_fix[ h->mb.i_chroma_pred_mode ] );
    }
    else if( i_mb_type == P_L0 )
    {
        int mvp[2];

        if( h->mb.i_partition == D_16x16 )
        {
            bs_write_ue( s, 0 );

            if( h->sh.i_num_ref_idx_l0_active > 1 )
            {
                bs_write_te( s, h->sh.i_num_ref_idx_l0_active - 1, h->mb.cache.ref[0][x264_scan8[0]] );
            }
            x264_mb_predict_mv( h, 0, 0, 4, mvp );
            bs_write_se( s, h->mb.cache.mv[0][x264_scan8[0]][0] - mvp[0] );
            bs_write_se( s, h->mb.cache.mv[0][x264_scan8[0]][1] - mvp[1] );
        }
        else if( h->mb.i_partition == D_16x8 )
        {
            bs_write_ue( s, 1 );
            if( h->sh.i_num_ref_idx_l0_active > 1 )
            {
                bs_write_te( s, h->sh.i_num_ref_idx_l0_active - 1, h->mb.cache.ref[0][x264_scan8[0]] );
                bs_write_te( s, h->sh.i_num_ref_idx_l0_active - 1, h->mb.cache.ref[0][x264_scan8[8]] );
            }

            x264_mb_predict_mv( h, 0, 0, 4, mvp );
            bs_write_se( s, h->mb.cache.mv[0][x264_scan8[0]][0] - mvp[0] );
            bs_write_se( s, h->mb.cache.mv[0][x264_scan8[0]][1] - mvp[1] );

            x264_mb_predict_mv( h, 0, 8, 4, mvp );
            bs_write_se( s, h->mb.cache.mv[0][x264_scan8[8]][0] - mvp[0] );
            bs_write_se( s, h->mb.cache.mv[0][x264_scan8[8]][1] - mvp[1] );
        }
        else if( h->mb.i_partition == D_8x16 )
        {
            bs_write_ue( s, 2 );
            if( h->sh.i_num_ref_idx_l0_active > 1 )
            {
                bs_write_te( s, h->sh.i_num_ref_idx_l0_active - 1, h->mb.cache.ref[0][x264_scan8[0]] );
                bs_write_te( s, h->sh.i_num_ref_idx_l0_active - 1, h->mb.cache.ref[0][x264_scan8[4]] );
            }

            x264_mb_predict_mv( h, 0, 0, 2, mvp );
            bs_write_se( s, h->mb.cache.mv[0][x264_scan8[0]][0] - mvp[0] );
            bs_write_se( s, h->mb.cache.mv[0][x264_scan8[0]][1] - mvp[1] );

            x264_mb_predict_mv( h, 0, 4, 2, mvp );
            bs_write_se( s, h->mb.cache.mv[0][x264_scan8[4]][0] - mvp[0] );
            bs_write_se( s, h->mb.cache.mv[0][x264_scan8[4]][1] - mvp[1] );
        }
    }
    else if( i_mb_type == P_8x8 )
    {
        int b_sub_ref0;

        if( h->mb.cache.ref[0][x264_scan8[0]] == 0 && h->mb.cache.ref[0][x264_scan8[4]] == 0 &&
            h->mb.cache.ref[0][x264_scan8[8]] == 0 && h->mb.cache.ref[0][x264_scan8[12]] == 0 )
        {
            bs_write_ue( s, 4 );
            b_sub_ref0 = 0;
        }
        else
        {
            bs_write_ue( s, 3 );
            b_sub_ref0 = 1;
        }
        /* sub mb type */
        for( i = 0; i < 4; i++ )
        {
            bs_write_ue( s, sub_mb_type_p_to_golomb[ h->mb.i_sub_partition[i] ] );
        }
        /* ref0 */
        if( h->sh.i_num_ref_idx_l0_active > 1 && b_sub_ref0 )
        {
            bs_write_te( s, h->sh.i_num_ref_idx_l0_active - 1, h->mb.cache.ref[0][x264_scan8[0]] );
            bs_write_te( s, h->sh.i_num_ref_idx_l0_active - 1, h->mb.cache.ref[0][x264_scan8[4]] );
            bs_write_te( s, h->sh.i_num_ref_idx_l0_active - 1, h->mb.cache.ref[0][x264_scan8[8]] );
            bs_write_te( s, h->sh.i_num_ref_idx_l0_active - 1, h->mb.cache.ref[0][x264_scan8[12]] );
        }

        for( i = 0; i < 4; i++ )
            cavlc_mb8x8_mvd( h, s, 0, i );
    }
    else if( i_mb_type == B_8x8 )
    {
        bs_write_ue( s, 22 );

        /* sub mb type */
        for( i = 0; i < 4; i++ )
        {
            bs_write_ue( s, sub_mb_type_b_to_golomb[ h->mb.i_sub_partition[i] ] );
        }
        /* ref */
        for( i = 0; i < 4; i++ )
        {
            if( x264_mb_partition_listX_table[0][ h->mb.i_sub_partition[i] ] )
            {
                bs_write_te( s, h->sh.i_num_ref_idx_l0_active - 1, h->mb.cache.ref[0][x264_scan8[i*4]] );
            }
        }
        for( i = 0; i < 4; i++ )
        {
            if( x264_mb_partition_listX_table[1][ h->mb.i_sub_partition[i] ] )
            {
                bs_write_te( s, h->sh.i_num_ref_idx_l1_active - 1, h->mb.cache.ref[1][x264_scan8[i*4]] );
            }
        }
        /* mvd */
        for( i = 0; i < 4; i++ )
            cavlc_mb8x8_mvd( h, s, 0, i );
        for( i = 0; i < 4; i++ )
            cavlc_mb8x8_mvd( h, s, 1, i );
    }
    else if( i_mb_type != B_DIRECT )
    {
        /* All B mode */
        /* Motion Vector */
        int i_list;
        int mvp[2];

        int b_list[2][2];

        /* init ref list utilisations */
        for( i = 0; i < 2; i++ )
        {
            b_list[0][i] = x264_mb_type_list0_table[i_mb_type][i];
            b_list[1][i] = x264_mb_type_list1_table[i_mb_type][i];
        }


        bs_write_ue( s, mb_type_b_to_golomb[ h->mb.i_partition - D_16x8 ][ i_mb_type - B_L0_L0 ] );

        for( i_list = 0; i_list < 2; i_list++ )
        {
            const int i_ref_max = i_list == 0 ? h->sh.i_num_ref_idx_l0_active : h->sh.i_num_ref_idx_l1_active;

            if( i_ref_max > 1 )
            {
                switch( h->mb.i_partition )
                {
                    case D_16x16:
                        if( b_list[i_list][0] ) bs_write_te( s, i_ref_max - 1, h->mb.cache.ref[i_list][x264_scan8[0]] );
                        break;
                    case D_16x8:
                        if( b_list[i_list][0] ) bs_write_te( s, i_ref_max - 1, h->mb.cache.ref[i_list][x264_scan8[0]] );
                        if( b_list[i_list][1] ) bs_write_te( s, i_ref_max - 1, h->mb.cache.ref[i_list][x264_scan8[8]] );
                        break;
                    case D_8x16:
                        if( b_list[i_list][0] ) bs_write_te( s, i_ref_max - 1, h->mb.cache.ref[i_list][x264_scan8[0]] );
                        if( b_list[i_list][1] ) bs_write_te( s, i_ref_max - 1, h->mb.cache.ref[i_list][x264_scan8[4]] );
                        break;
                }
            }
        }
        for( i_list = 0; i_list < 2; i_list++ )
        {
            switch( h->mb.i_partition )
            {
                case D_16x16:
                    if( b_list[i_list][0] )
                    {
                        x264_mb_predict_mv( h, i_list, 0, 4, mvp );
                        bs_write_se( s, h->mb.cache.mv[i_list][x264_scan8[0]][0] - mvp[0] );
                        bs_write_se( s, h->mb.cache.mv[i_list][x264_scan8[0]][1] - mvp[1] );
                    }
                    break;
                case D_16x8:
                    if( b_list[i_list][0] )
                    {
                        x264_mb_predict_mv( h, i_list, 0, 4, mvp );
                        bs_write_se( s, h->mb.cache.mv[i_list][x264_scan8[0]][0] - mvp[0] );
                        bs_write_se( s, h->mb.cache.mv[i_list][x264_scan8[0]][1] - mvp[1] );
                    }
                    if( b_list[i_list][1] )
                    {
                        x264_mb_predict_mv( h, i_list, 8, 4, mvp );
                        bs_write_se( s, h->mb.cache.mv[i_list][x264_scan8[8]][0] - mvp[0] );
                        bs_write_se( s, h->mb.cache.mv[i_list][x264_scan8[8]][1] - mvp[1] );
                    }
                    break;
                case D_8x16:
                    if( b_list[i_list][0] )
                    {
                        x264_mb_predict_mv( h, i_list, 0, 2, mvp );
                        bs_write_se( s, h->mb.cache.mv[i_list][x264_scan8[0]][0] - mvp[0] );
                        bs_write_se( s, h->mb.cache.mv[i_list][x264_scan8[0]][1] - mvp[1] );
                    }
                    if( b_list[i_list][1] )
                    {
                        x264_mb_predict_mv( h, i_list, 4, 2, mvp );
                        bs_write_se( s, h->mb.cache.mv[i_list][x264_scan8[4]][0] - mvp[0] );
                        bs_write_se( s, h->mb.cache.mv[i_list][x264_scan8[4]][1] - mvp[1] );
                    }
                    break;
            }
        }
    }
    else if( i_mb_type == B_DIRECT )
    {
        bs_write_ue( s, 0 );
    }
    else
    {
        x264_log(h, X264_LOG_ERROR, "invalid/unhandled mb_type\n" );
        return;
    }

#ifndef RDO_SKIP_BS
    i_mb_pos_tex = bs_pos( s );
    h->stat.frame.i_hdr_bits += i_mb_pos_tex - i_mb_pos_start;
#endif

    /* Coded block patern */
    if( i_mb_type == I_4x4 || i_mb_type == I_8x8 )
    {
        bs_write_ue( s, intra4x4_cbp_to_golomb[( h->mb.i_cbp_chroma << 4 )|h->mb.i_cbp_luma] );
    }
    else if( i_mb_type != I_16x16 )
    {
        bs_write_ue( s, inter_cbp_to_golomb[( h->mb.i_cbp_chroma << 4 )|h->mb.i_cbp_luma] );
    }

    /* transform size 8x8 flag */
    if( h->mb.cache.b_transform_8x8_allowed && h->mb.i_cbp_luma && !IS_INTRA(i_mb_type) )
    {
        bs_write1( s, h->mb.b_transform_8x8 );
    }

    /* write residual */
    if( i_mb_type == I_16x16 )
    {
        cavlc_qp_delta( h, s );

        /* DC Luma */
        block_residual_write_cavlc( h, s, BLOCK_INDEX_LUMA_DC , h->dct.luma16x16_dc, 16 );

        /* AC Luma */
        if( h->mb.i_cbp_luma != 0 )
            for( i = 0; i < 16; i++ )
                block_residual_write_cavlc( h, s, i, h->dct.block[i].residual_ac, 15 );
    }
    else if( h->mb.i_cbp_luma != 0 || h->mb.i_cbp_chroma != 0 )
    {
        cavlc_qp_delta( h, s );
        x264_macroblock_luma_write_cavlc( h, s, 0, 3 );
    }
    if( h->mb.i_cbp_chroma != 0 )
    {
        /* Chroma DC residual present */
        block_residual_write_cavlc( h, s, BLOCK_INDEX_CHROMA_DC, h->dct.chroma_dc[0], 4 );
        block_residual_write_cavlc( h, s, BLOCK_INDEX_CHROMA_DC, h->dct.chroma_dc[1], 4 );
        if( h->mb.i_cbp_chroma&0x02 ) /* Chroma AC residual present */
            for( i = 0; i < 8; i++ )
                block_residual_write_cavlc( h, s, 16 + i, h->dct.block[16+i].residual_ac, 15 );
    }

#ifndef RDO_SKIP_BS
    if( IS_INTRA( i_mb_type ) )
        h->stat.frame.i_itex_bits += bs_pos(s) - i_mb_pos_tex;
    else
        h->stat.frame.i_ptex_bits += bs_pos(s) - i_mb_pos_tex;
#endif
}

#ifdef RDO_SKIP_BS
/*****************************************************************************
 * RD only; doesn't generate a valid bitstream
 * doesn't write cbp or chroma dc (I don't know how much this matters)
 * works on all partition sizes except 16x16
 * for sub8x8, call once per 8x8 block
 *****************************************************************************/
int x264_partition_size_cavlc( x264_t *h, int i8, int i_pixel )
{
    bs_t s;
    const int i_mb_type = h->mb.i_type;
    int j;

    s.i_bits_encoded = 0;

    if( i_mb_type == P_8x8 )
    {
        bs_write_ue( &s, sub_mb_type_p_to_golomb[ h->mb.i_sub_partition[i8] ] );
        if( h->sh.i_num_ref_idx_l0_active > 1 )
            bs_write_te( &s, h->sh.i_num_ref_idx_l0_active - 1, h->mb.cache.ref[0][x264_scan8[4*i8]] );
        cavlc_mb8x8_mvd( h, &s, 0, i8 );
    }
    else if( i_mb_type == P_L0 )
    {
        if( h->sh.i_num_ref_idx_l0_active > 1 )
            bs_write_te( &s, h->sh.i_num_ref_idx_l0_active - 1, h->mb.cache.ref[0][x264_scan8[4*i8]] );
        if( h->mb.i_partition == D_16x8 )
            cavlc_mb_mvd( h, &s, 0, 4*i8, 4 );
        else //8x16
            cavlc_mb_mvd( h, &s, 0, 4*i8, 2 );
    }
    else if( i_mb_type == B_8x8 )
    {
        bs_write_ue( &s, sub_mb_type_b_to_golomb[ h->mb.i_sub_partition[i8] ] );

        if( h->sh.i_num_ref_idx_l0_active > 1
            && x264_mb_partition_listX_table[0][ h->mb.i_sub_partition[i8] ] )
            bs_write_te( &s, h->sh.i_num_ref_idx_l0_active - 1, h->mb.cache.ref[0][x264_scan8[4*i8]] );
        if( h->sh.i_num_ref_idx_l1_active > 1
            && x264_mb_partition_listX_table[1][ h->mb.i_sub_partition[i8] ] )
            bs_write_te( &s, h->sh.i_num_ref_idx_l1_active - 1, h->mb.cache.ref[1][x264_scan8[4*i8]] );

        cavlc_mb8x8_mvd( h, &s, 0, i8 );
        cavlc_mb8x8_mvd( h, &s, 1, i8 );
    }
    else
    {
        x264_log(h, X264_LOG_ERROR, "invalid/unhandled mb_type\n" );
        return 0;
    }

    for( j = (i_pixel < PIXEL_8x8); j >= 0; j-- )
    {
        x264_macroblock_luma_write_cavlc( h, &s, i8, i8 );

        block_residual_write_cavlc( h, &s, i8,   h->dct.block[16+i8  ].residual_ac, 15 );
        block_residual_write_cavlc( h, &s, i8+4, h->dct.block[16+i8+4].residual_ac, 15 );

        i8 += x264_pixel_size[i_pixel].h >> 3;
    }

    return s.i_bits_encoded;
}

static int cavlc_intra4x4_pred_size( x264_t *h, int i4, int i_mode )
{
    if( x264_mb_predict_intra4x4_mode( h, i4 ) == x264_mb_pred_mode4x4_fix( i_mode ) )
        return 1;
    else
        return 4;
}

static int x264_partition_i8x8_size_cavlc( x264_t *h, int i8, int i_mode )
{
    int i4, i;
    h->out.bs.i_bits_encoded = cavlc_intra4x4_pred_size( h, 4*i8, i_mode );
    for( i4 = 0; i4 < 4; i4++ )
    {
        for( i = 0; i < 16; i++ )
            h->dct.block[i4+i8*4].luma4x4[i] = h->dct.luma8x8[i8][i4+i*4];
        h->mb.cache.non_zero_count[x264_scan8[i4+i8*4]] =
            array_non_zero_count( h->dct.block[i4+i8*4].luma4x4, 16 );
        block_residual_write_cavlc( h, &h->out.bs, i4+i8*4, h->dct.block[i4+i8*4].luma4x4, 16 );
    }
    return h->out.bs.i_bits_encoded;
}

static int x264_partition_i4x4_size_cavlc( x264_t *h, int i4, int i_mode )
{
    h->out.bs.i_bits_encoded = cavlc_intra4x4_pred_size( h, i4, i_mode );
    block_residual_write_cavlc( h, &h->out.bs, i4, h->dct.block[i4].luma4x4, 16 );
    return h->out.bs.i_bits_encoded;
}
#endif