cavlc.c

x264 encoder in TI ccs.

/*****************************************************************************
 * cavlc.c: h264 encoder library
 *****************************************************************************
 * Copyright (C) 2003 Laurent Aimar
 * $Id: cavlc.c,v 1.1 2004/06/03 19:27:08 fenrir Exp $
 *
 * Authors: Laurent Aimar <[e-mail]>
 *
 * 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., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
 *****************************************************************************/

#include <stdio.h>
#include <string.h>

#include "common.h"
#include "vlc.h"
#include "enmacroblock.h"

static const uint8_t intra4x4_cbp_to_golomb[48]=
{
  3, 29, 30, 17, 31, 18, 37,  8, 32, 38, 19,  9, 20, 10, 11,  2,
 16, 33, 34, 21, 35, 22, 39,  4, 36, 40, 23,  5, 24,  6,  7,  1,
 41, 42, 43, 25, 44, 26, 46, 12, 45, 47, 27, 13, 28, 14, 15,  0
};
static const uint8_t inter_cbp_to_golomb[48]=
{
  0,  2,  3,  7,  4,  8, 17, 13,  5, 18,  9, 14, 10, 15, 16, 11,
  1, 32, 33, 36, 34, 37, 44, 40, 35, 45, 38, 41, 39, 42, 43, 19,
  6, 24, 25, 20, 26, 21, 46, 28, 27, 47, 22, 29, 23, 30, 31, 12
};
static const int8_t mb_type_b_to_golomb[3][9]=
{
    { 4,  8, 12, 10,  6, 14, 16, 18, 20 }, /* D_16x8 */
    { 5,  9, 13, 11,  7, 15, 17, 19, 21 }, /* D_8x16 */
    { 1, -1, -1, -1,  2, -1, -1, -1,  3 }  /* D_16x16 */
};
static const uint8_t sub_mb_type_p_to_golomb[4]=
{
    3, 1, 2, 0
};
static const uint8_t sub_mb_type_b_to_golomb[13]=
{
    10,  4,  5,  1, 11,  6,  7,  2, 12,  8,  9,  3,  0
};

#define BLOCK_INDEX_CHROMA_DC   (-1)
#define BLOCK_INDEX_LUMA_DC     (-2)

static inline void bs_write_vlc( bs_t *s, vlc_t v )
{
    bs_write( s, v.i_size, v.i_bits );
}

/****************************************************************************
 * block_residual_write_cavlc:
 ****************************************************************************/
static void block_residual_write_cavlc( x264_t *h, bs_t *s, int i_idx, int *l, int i_count )
{
    int level[16], run[16];
    int i_total, i_trailing;
    int i_total_zero;
    int i_last;
    unsigned int i_sign;

    int i;
    int i_zero_left;
    int i_suffix_length;

    /* first find i_last */
    i_last = i_count - 1;
    while( i_last >= 0 && l[i_last] == 0 )
    {
        i_last--;
    }

    i_sign = 0;
    i_total = 0;
    i_trailing = 0;
    i_total_zero = 0;

    if( i_last >= 0 )
    {
        int b_trailing = 1;
        int idx = 0;

        /* level and run and total */
        while( i_last >= 0 )
        {
            level[idx] = l[i_last--];

            run[idx] = 0;
            while( i_last >= 0 && l[i_last] == 0 )
            {
                run[idx]++;
                i_last--;
            }

            i_total++;
            i_total_zero += run[idx];

            if( b_trailing && abs( level[idx] ) == 1 && i_trailing < 3 )
            {
                i_sign <<= 1;
                if( level[idx] < 0 )
                {
                    i_sign |= 0x01;
                }

                i_trailing++;
            }
            else
            {
                b_trailing = 0;
            }

            idx++;
        }
    }

    /* total/trailing */
    if( i_idx == BLOCK_INDEX_CHROMA_DC )
    {
        bs_write_vlc( s, x264_coeff_token[4][i_total*4+i_trailing] );
    }
    else
    {
        /* x264_mb_predict_non_zero_code return 0 <-> (16+16+1)>>1 = 16 */
        static const int ct_index[17] = {0,0,1,1,2,2,2,2,3,3,3,3,3,3,3,3,3 };
        int nC;

        if( i_idx == BLOCK_INDEX_LUMA_DC )
        {
            nC = x264_mb_predict_non_zero_code( h, 0 );
        }
        else
        {
            nC = x264_mb_predict_non_zero_code( h, i_idx );
        }

        bs_write_vlc( s, x264_coeff_token[ct_index[nC]][i_total*4+i_trailing] );
    }

    if( i_total <= 0 )
    {
        return;
    }

    i_suffix_length = i_total > 10 && i_trailing < 3 ? 1 : 0;
    if( i_trailing > 0 )
    {
        bs_write( s, i_trailing, i_sign );
    }
    for( i = i_trailing; i < i_total; i++ )
    {
        int i_level_code;

        /* calculate level code */
        if( level[i] < 0 )
        {
            i_level_code = -2*level[i] - 1;
        }
        else /* if( level[i] > 0 ) */
        {
            i_level_code = 2 * level[i] - 2;
        }
        if( i == i_trailing && i_trailing < 3 )
        {
            i_level_code -=2; /* as level[i] can't be 1 for the first one if i_trailing < 3 */
        }

        if( ( i_level_code >> i_suffix_length ) < 14 )
        {
            bs_write_vlc( s, x264_level_prefix[i_level_code >> i_suffix_length] );
            if( i_suffix_length > 0 )
            {
                bs_write( s, i_suffix_length, i_level_code );
            }
        }
        else if( i_suffix_length == 0 && i_level_code < 30 )
        {
            bs_write_vlc( s, x264_level_prefix[14] );
            bs_write( s, 4, i_level_code - 14 );
        }
        else if( i_suffix_length > 0 && ( i_level_code >> i_suffix_length ) == 14 )
        {
            bs_write_vlc( s, x264_level_prefix[14] );
            bs_write( s, i_suffix_length, i_level_code );
        }
        else
        {
            bs_write_vlc( s, x264_level_prefix[15] );
            i_level_code -= 15 << i_suffix_length;
            if( i_suffix_length == 0 )
            {
                i_level_code -= 15;
            }

            if( i_level_code >= ( 1 << 12 ) || i_level_code < 0 )
            {
                x264_log(h, X264_LOG_WARNING, "OVERFLOW levelcode=%d\n", i_level_code );
            }

            bs_write( s, 12, i_level_code );    /* check overflow ?? */
        }

        if( i_suffix_length == 0 )
        {
            i_suffix_length++;
        }
        if( abs( level[i] ) > ( 3 << ( i_suffix_length - 1 ) ) && i_suffix_length < 6 )
        {
            i_suffix_length++;
        }
    }

    if( i_total < i_count )
    {
        if( i_idx == BLOCK_INDEX_CHROMA_DC )
        {
            bs_write_vlc( s, x264_total_zeros_dc[i_total-1][i_total_zero] );
        }
        else
        {
            bs_write_vlc( s, x264_total_zeros[i_total-1][i_total_zero] );
        }
    }

    for( i = 0, i_zero_left = i_total_zero; i < i_total - 1; i++ )
    {
        int i_zl;

        if( i_zero_left <= 0 )
        {
            break;
        }

        i_zl = X264_MIN( i_zero_left - 1, 6 );

        bs_write_vlc( s, x264_run_before[i_zl][run[i]] );

        i_zero_left -= run[i];
    }
}

static void cavlc_qp_delta( x264_t *h, bs_t *s )
{
    int i_dqp = h->mb.i_qp - h->mb.i_last_qp;
    if( i_dqp )
    {
        if( i_dqp < -26 )
            i_dqp += 52;
        else if( i_dqp > 25 )
            i_dqp -= 52;
    }
    bs_write_se( s, i_dqp );
}

static void cavlc_mb_mvd( x264_t *h, bs_t *s, int i_list, int idx, int width )
{
    int mvp[2];
    x264_mb_predict_mv( h, i_list, idx, width, mvp );
    bs_write_se( s, h->mb.cache.mv[i_list][x264_scan8[idx]][0] - mvp[0] );
    bs_write_se( s, h->mb.cache.mv[i_list][x264_scan8[idx]][1] - mvp[1] );
}

static void cavlc_mb8x8_mvd( x264_t *h, bs_t *s, int i_list, int i )
{
    if( !x264_mb_partition_listX_table[i_list][ h->mb.i_sub_partition[i] ] )
        return;

    switch( h->mb.i_sub_partition[i] )
    {
        case D_L0_8x8:
        case D_L1_8x8:
        case D_BI_8x8:
            cavlc_mb_mvd( h, s, i_list, 4*i, 2 );
            break;
        case D_L0_8x4:
        case D_L1_8x4:
        case D_BI_8x4:
            cavlc_mb_mvd( h, s, i_list, 4*i+0, 2 );
            cavlc_mb_mvd( h, s, i_list, 4*i+2, 2 );
            break;
        case D_L0_4x8:
        case D_L1_4x8:
        case D_BI_4x8:
            cavlc_mb_mvd( h, s, i_list, 4*i+0, 1 );
            cavlc_mb_mvd( h, s, i_list, 4*i+1, 1 );
            break;
        case D_L0_4x4:
        case D_L1_4x4:
        case D_BI_4x4:
            cavlc_mb_mvd( h, s, i_list, 4*i+0, 1 );
            cavlc_mb_mvd( h, s, i_list, 4*i+1, 1 );
            cavlc_mb_mvd( h, s, i_list, 4*i+2, 1 );
            cavlc_mb_mvd( h, s, i_list, 4*i+3, 1 );
            break;
    }
}

static inline void x264_macroblock_luma_write_cavlc( x264_t *h, bs_t *s, int i8start, int i8end )
{
    int i8, i4, i;
    if( h->mb.b_transform_8x8 )
    {
        /* shuffle 8x8 dct coeffs into 4x4 lists */
        for( i8 = i8start; i8 <= i8end; i8++ )
            if( h->mb.i_cbp_luma & (1 << i8) )
                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 );
                }
    }

    for( i8 = i8start; i8 <= i8end; i8++ )
        if( h->mb.i_cbp_luma & (1 << i8) )
            for( i4 = 0; i4 < 4; i4++ )
                block_residual_write_cavlc( h, s, i4+i8*4, h->dct.block[i4+i8*4].luma4x4, 16 );
}

/*****************************************************************************
 * x264_macroblock_write:
 *****************************************************************************/
void x264_macroblock_write_cavlc( x264_t *h, bs_t *s )
{
    const int i_mb_type = h->mb.i_type;
    int i_mb_i_offset;
    int i;

#ifndef RDO_SKIP_BS
    const int i_mb_pos_start = bs_pos( s );
    int       i_mb_pos_tex;
#endif

    switch( h->sh.i_type )
    {
        case SLICE_TYPE_I:
            i_mb_i_offset = 0;
            break;
        case SLICE_TYPE_P:
            i_mb_i_offset = 5;
            break;
        case SLICE_TYPE_B:
            i_mb_i_offset = 23;
            break;
        default:
            x264_log(h, X264_LOG_ERROR, "internal error or slice unsupported\n" );
            return;
    }

    /* Write:
      - type
      - prediction
      - mv */
    if( i_mb_type == I_PCM )
    {
        /* Untested */
        bs_write_ue( s, i_mb_i_offset + 25 );

#ifdef RDO_SKIP_BS
        s->i_bits_encoded += 384*8;
#else
        bs_align_0( s );
        /* Luma */
        for( i = 0; i < 16*16; i++ )
        {
            const int x = 16 * h->mb.i_mb_x + (i % 16);
            const int y = 16 * h->mb.i_mb_y + (i / 16);
            bs_write( s, 8, h->fenc->plane[0][y*h->mb.pic.i_stride[0]+x] );
        }
        /* Cb */
        for( i = 0; i < 8*8; i++ )
        {
            const int x = 8 * h->mb.i_mb_x + (i % 8);
            const int y = 8 * h->mb.i_mb_y + (i / 8);
            bs_write( s, 8, h->fenc->plane[1][y*h->mb.pic.i_stride[1]+x] );
        }
        /* Cr */
        for( i = 0; i < 8*8; i++ )
        {
            const int x = 8 * h->mb.i_mb_x + (i % 8);
            const int y = 8 * h->mb.i_mb_y + (i / 8);
            bs_write( s, 8, h->fenc->plane[2][y*h->mb.pic.i_stride[2]+x] );
        }
#endif