PeerStreamer

/*

 * RV30/40 decoder common data

 * Copyright (c) 2007 Mike Melanson, Konstantin Shishkov

 *

 * This file is part of Libav.

 *

 * Libav is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * Libav 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with Libav; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

/**

 * @file

 * RV30/40 decoder common data

 */

#include "avcodec.h"

#include "dsputil.h"

#include "mpegvideo.h"

#include "golomb.h"

#include "mathops.h"

#include "rectangle.h"

#include "rv34vlc.h"

#include "rv34data.h"

#include "rv34.h"

//#define DEBUG

static inline void ZERO8x2(void* dst, int stride)

{

    fill_rectangle(dst,                 1, 2, stride, 0, 4);

    fill_rectangle(((uint8_t*)(dst))+4, 1, 2, stride, 0, 4);

}

/** translation of RV30/40 macroblock types to lavc ones */

static const int rv34_mb_type_to_lavc[12] = {

    MB_TYPE_INTRA,

    MB_TYPE_INTRA16x16              | MB_TYPE_SEPARATE_DC,

    MB_TYPE_16x16   | MB_TYPE_L0,

    MB_TYPE_8x8     | MB_TYPE_L0,

    MB_TYPE_16x16   | MB_TYPE_L0,

    MB_TYPE_16x16   | MB_TYPE_L1,

    MB_TYPE_SKIP,

    MB_TYPE_DIRECT2 | MB_TYPE_16x16,

    MB_TYPE_16x8    | MB_TYPE_L0,

    MB_TYPE_8x16    | MB_TYPE_L0,

    MB_TYPE_16x16   | MB_TYPE_L0L1,

    MB_TYPE_16x16   | MB_TYPE_L0    | MB_TYPE_SEPARATE_DC

};

static RV34VLC intra_vlcs[NUM_INTRA_TABLES], inter_vlcs[NUM_INTER_TABLES];

/**

 * @defgroup vlc RV30/40 VLC generating functions

 * @{

 */

static const int table_offs[] = {

      0,   1818,   3622,   4144,   4698,   5234,   5804,   5868,   5900,   5932,

   5996,   6252,   6316,   6348,   6380,   7674,   8944,  10274,  11668,  12250,

  14060,  15846,  16372,  16962,  17512,  18148,  18180,  18212,  18244,  18308,

  18564,  18628,  18660,  18692,  20036,  21314,  22648,  23968,  24614,  26384,

  28190,  28736,  29366,  29938,  30608,  30640,  30672,  30704,  30768,  31024,

  31088,  31120,  31184,  32570,  33898,  35236,  36644,  37286,  39020,  40802,

  41368,  42052,  42692,  43348,  43380,  43412,  43444,  43476,  43604,  43668,

  43700,  43732,  45100,  46430,  47778,  49160,  49802,  51550,  53340,  53972,

  54648,  55348,  55994,  56122,  56154,  56186,  56218,  56346,  56410,  56442,

  56474,  57878,  59290,  60636,  62036,  62682,  64460,  64524,  64588,  64716,

  64844,  66076,  67466,  67978,  68542,  69064,  69648,  70296,  72010,  72074,

  72138,  72202,  72330,  73572,  74936,  75454,  76030,  76566,  77176,  77822,

  79582,  79646,  79678,  79742,  79870,  81180,  82536,  83064,  83672,  84242,

  84934,  85576,  87384,  87448,  87480,  87544,  87672,  88982,  90340,  90902,

  91598,  92182,  92846,  93488,  95246,  95278,  95310,  95374,  95502,  96878,

  98266,  98848,  99542, 100234, 100884, 101524, 103320, 103352, 103384, 103416,

 103480, 104874, 106222, 106910, 107584, 108258, 108902, 109544, 111366, 111398,

 111430, 111462, 111494, 112878, 114320, 114988, 115660, 116310, 116950, 117592

};

static VLC_TYPE table_data[117592][2];

/**

 * Generate VLC from codeword lengths.

 * @param bits   codeword lengths (zeroes are accepted)

 * @param size   length of input data

 * @param vlc    output VLC

 * @param insyms symbols for input codes (NULL for default ones)

 * @param num    VLC table number (for static initialization)

 */

static void rv34_gen_vlc(const uint8_t *bits, int size, VLC *vlc, const uint8_t *insyms,

                         const int num)

{

    int i;

    int counts[17] = {0}, codes[17];

    uint16_t cw[MAX_VLC_SIZE], syms[MAX_VLC_SIZE];

    uint8_t bits2[MAX_VLC_SIZE];

    int maxbits = 0, realsize = 0;

    for(i = 0; i < size; i++){

        if(bits[i]){

            bits2[realsize] = bits[i];

            syms[realsize] = insyms ? insyms[i] : i;

            realsize++;

            maxbits = FFMAX(maxbits, bits[i]);

            counts[bits[i]]++;

        }

    }

    codes[0] = 0;

    for(i = 0; i < 16; i++)

        codes[i+1] = (codes[i] + counts[i]) << 1;

    for(i = 0; i < realsize; i++)

        cw[i] = codes[bits2[i]]++;

    vlc->table = &table_data[table_offs[num]];

    vlc->table_allocated = table_offs[num + 1] - table_offs[num];

    init_vlc_sparse(vlc, FFMIN(maxbits, 9), realsize,

                    bits2, 1, 1,

                    cw,    2, 2,

                    syms,  2, 2, INIT_VLC_USE_NEW_STATIC);

}

/**

 * Initialize all tables.

 */

static av_cold void rv34_init_tables(void)

{

    int i, j, k;

    for(i = 0; i < NUM_INTRA_TABLES; i++){

        for(j = 0; j < 2; j++){

            rv34_gen_vlc(rv34_table_intra_cbppat   [i][j], CBPPAT_VLC_SIZE,   &intra_vlcs[i].cbppattern[j],     NULL, 19*i + 0 + j);

            rv34_gen_vlc(rv34_table_intra_secondpat[i][j], OTHERBLK_VLC_SIZE, &intra_vlcs[i].second_pattern[j], NULL, 19*i + 2 + j);

            rv34_gen_vlc(rv34_table_intra_thirdpat [i][j], OTHERBLK_VLC_SIZE, &intra_vlcs[i].third_pattern[j],  NULL, 19*i + 4 + j);

            for(k = 0; k < 4; k++){

                rv34_gen_vlc(rv34_table_intra_cbp[i][j+k*2],  CBP_VLC_SIZE,   &intra_vlcs[i].cbp[j][k],         rv34_cbp_code, 19*i + 6 + j*4 + k);

            }

        }

        for(j = 0; j < 4; j++){

            rv34_gen_vlc(rv34_table_intra_firstpat[i][j], FIRSTBLK_VLC_SIZE, &intra_vlcs[i].first_pattern[j], NULL, 19*i + 14 + j);

        }

        rv34_gen_vlc(rv34_intra_coeff[i], COEFF_VLC_SIZE, &intra_vlcs[i].coefficient, NULL, 19*i + 18);

    }

    for(i = 0; i < NUM_INTER_TABLES; i++){

        rv34_gen_vlc(rv34_inter_cbppat[i], CBPPAT_VLC_SIZE, &inter_vlcs[i].cbppattern[0], NULL, i*12 + 95);

        for(j = 0; j < 4; j++){

            rv34_gen_vlc(rv34_inter_cbp[i][j], CBP_VLC_SIZE, &inter_vlcs[i].cbp[0][j], rv34_cbp_code, i*12 + 96 + j);

        }

        for(j = 0; j < 2; j++){

            rv34_gen_vlc(rv34_table_inter_firstpat [i][j], FIRSTBLK_VLC_SIZE, &inter_vlcs[i].first_pattern[j],  NULL, i*12 + 100 + j);

            rv34_gen_vlc(rv34_table_inter_secondpat[i][j], OTHERBLK_VLC_SIZE, &inter_vlcs[i].second_pattern[j], NULL, i*12 + 102 + j);

            rv34_gen_vlc(rv34_table_inter_thirdpat [i][j], OTHERBLK_VLC_SIZE, &inter_vlcs[i].third_pattern[j],  NULL, i*12 + 104 + j);

        }

        rv34_gen_vlc(rv34_inter_coeff[i], COEFF_VLC_SIZE, &inter_vlcs[i].coefficient, NULL, i*12 + 106);

    }

}

/** @} */ // vlc group

/**

 * @defgroup transform RV30/40 inverse transform functions

 * @{

 */

static av_always_inline void rv34_row_transform(int temp[16], DCTELEM *block)

{

    int i;

    for(i=0; i<4; i++){

        const int z0= 13*(block[i+8*0] +    block[i+8*2]);

        const int z1= 13*(block[i+8*0] -    block[i+8*2]);

        const int z2=  7* block[i+8*1] - 17*block[i+8*3];

        const int z3= 17* block[i+8*1] +  7*block[i+8*3];

        temp[4*i+0]= z0+z3;

        temp[4*i+1]= z1+z2;

        temp[4*i+2]= z1-z2;

        temp[4*i+3]= z0-z3;

    }

}

/**

 * Real Video 3.0/4.0 inverse transform

 * Code is almost the same as in SVQ3, only scaling is different.

 */

static void rv34_inv_transform(DCTELEM *block){

    int temp[16];

    int i;

    rv34_row_transform(temp, block);

    for(i=0; i<4; i++){

        const int z0= 13*(temp[4*0+i] +    temp[4*2+i]) + 0x200;

        const int z1= 13*(temp[4*0+i] -    temp[4*2+i]) + 0x200;

        const int z2=  7* temp[4*1+i] - 17*temp[4*3+i];

        const int z3= 17* temp[4*1+i] +  7*temp[4*3+i];

        block[i*8+0]= (z0 + z3)>>10;

        block[i*8+1]= (z1 + z2)>>10;

        block[i*8+2]= (z1 - z2)>>10;

        block[i*8+3]= (z0 - z3)>>10;

    }

}

/**

 * RealVideo 3.0/4.0 inverse transform for DC block

 *

 * Code is almost the same as rv34_inv_transform()

 * but final coefficients are multiplied by 1.5 and have no rounding.

 */

static void rv34_inv_transform_noround(DCTELEM *block){

    int temp[16];

    int i;

    rv34_row_transform(temp, block);

    for(i=0; i<4; i++){

        const int z0= 13*(temp[4*0+i] +    temp[4*2+i]);

        const int z1= 13*(temp[4*0+i] -    temp[4*2+i]);

        const int z2=  7* temp[4*1+i] - 17*temp[4*3+i];

        const int z3= 17* temp[4*1+i] +  7*temp[4*3+i];

        block[i*8+0]= ((z0 + z3)*3)>>11;

        block[i*8+1]= ((z1 + z2)*3)>>11;

        block[i*8+2]= ((z1 - z2)*3)>>11;

        block[i*8+3]= ((z0 - z3)*3)>>11;

    }

}

/** @} */ // transform

/**

 * @defgroup block RV30/40 4x4 block decoding functions

 * @{

 */

/**

 * Decode coded block pattern.

 */

static int rv34_decode_cbp(GetBitContext *gb, RV34VLC *vlc, int table)

{

    int pattern, code, cbp=0;

    int ones;

    static const int cbp_masks[3] = {0x100000, 0x010000, 0x110000};

    static const int shifts[4] = { 0, 2, 8, 10 };

    const int *curshift = shifts;

    int i, t, mask;

    code = get_vlc2(gb, vlc->cbppattern[table].table, 9, 2);

    pattern = code & 0xF;

    code >>= 4;

    ones = rv34_count_ones[pattern];

    for(mask = 8; mask; mask >>= 1, curshift++){

        if(pattern & mask)

            cbp |= get_vlc2(gb, vlc->cbp[table][ones].table, vlc->cbp[table][ones].bits, 1) << curshift[0];

    }

    for(i = 0; i < 4; i++){

        t = modulo_three_table[code][i];

        if(t == 1)

            cbp |= cbp_masks[get_bits1(gb)] << i;

        if(t == 2)

            cbp |= cbp_masks[2] << i;

    }

    return cbp;

}

/**

 * Get one coefficient value from the bistream and store it.

 */

static inline void decode_coeff(DCTELEM *dst, int coef, int esc, GetBitContext *gb, VLC* vlc)

{

    if(coef){

        if(coef == esc){

            coef = get_vlc2(gb, vlc->table, 9, 2);

            if(coef > 23){

                coef -= 23;

                coef = 22 + ((1 << coef) | get_bits(gb, coef));

            }

            coef += esc;

        }

        if(get_bits1(gb))

            coef = -coef;

        *dst = coef;

    }

}

/**

 * Decode 2x2 subblock of coefficients.

 */

static inline void decode_subblock(DCTELEM *dst, int code, const int is_block2, GetBitContext *gb, VLC *vlc)

{

    int coeffs[4];

    coeffs[0] = modulo_three_table[code][0];

    coeffs[1] = modulo_three_table[code][1];

    coeffs[2] = modulo_three_table[code][2];

    coeffs[3] = modulo_three_table[code][3];

    decode_coeff(dst  , coeffs[0], 3, gb, vlc);

    if(is_block2){

        decode_coeff(dst+8, coeffs[1], 2, gb, vlc);

        decode_coeff(dst+1, coeffs[2], 2, gb, vlc);

    }else{

        decode_coeff(dst+1, coeffs[1], 2, gb, vlc);

        decode_coeff(dst+8, coeffs[2], 2, gb, vlc);

    }

    decode_coeff(dst+9, coeffs[3], 2, gb, vlc);

}

/**

 * Decode coefficients for 4x4 block.

 *

 * This is done by filling 2x2 subblocks with decoded coefficients

 * in this order (the same for subblocks and subblock coefficients):

 *  o--o

 *    /

 *   /

 *  o--o

 */

static inline void rv34_decode_block(DCTELEM *dst, GetBitContext *gb, RV34VLC *rvlc, int fc, int sc)

{

    int code, pattern;

    code = get_vlc2(gb, rvlc->first_pattern[fc].table, 9, 2);

    pattern = code & 0x7;

    code >>= 3;

    decode_subblock(dst, code, 0, gb, &rvlc->coefficient);

    if(pattern & 4){

        code = get_vlc2(gb, rvlc->second_pattern[sc].table, 9, 2);

        decode_subblock(dst + 2, code, 0, gb, &rvlc->coefficient);

    }

    if(pattern & 2){ // Looks like coefficients 1 and 2 are swapped for this block

        code = get_vlc2(gb, rvlc->second_pattern[sc].table, 9, 2);

        decode_subblock(dst + 8*2, code, 1, gb, &rvlc->coefficient);

    }

    if(pattern & 1){

        code = get_vlc2(gb, rvlc->third_pattern[sc].table, 9, 2);

        decode_subblock(dst + 8*2+2, code, 0, gb, &rvlc->coefficient);

    }

}

/**

 * Dequantize ordinary 4x4 block.

 * @todo optimize

 */

static inline void rv34_dequant4x4(DCTELEM *block, int Qdc, int Q)

{

    int i, j;

    block[0] = (block[0] * Qdc + 8) >> 4;

    for(i = 0; i < 4; i++)

        for(j = !i; j < 4; j++)

            block[j + i*8] = (block[j + i*8] * Q + 8) >> 4;

}

/**

 * Dequantize 4x4 block of DC values for 16x16 macroblock.

 * @todo optimize

 */

static inline void rv34_dequant4x4_16x16(DCTELEM *block, int Qdc, int Q)

{

    int i;

    for(i = 0; i < 3; i++)

         block[rv34_dezigzag[i]] = (block[rv34_dezigzag[i]] * Qdc + 8) >> 4;

    for(; i < 16; i++)

         block[rv34_dezigzag[i]] = (block[rv34_dezigzag[i]] * Q + 8) >> 4;

}

/** @} */ //block functions

/**

 * @defgroup rv3040_bitstream RV30/40 bitstream parsing

 * @{

 */

/**

 * Decode starting slice position.

 * @todo Maybe replace with ff_h263_decode_mba() ?

 */

int ff_rv34_get_start_offset(GetBitContext *gb, int mb_size)

{

    int i;

    for(i = 0; i < 5; i++)

        if(rv34_mb_max_sizes[i] >= mb_size - 1)

            break;

    return rv34_mb_bits_sizes[i];

}

/**

 * Select VLC set for decoding from current quantizer, modifier and frame type.

 */

static inline RV34VLC* choose_vlc_set(int quant, int mod, int type)

{

    if(mod == 2 && quant < 19) quant += 10;

    else if(mod && quant < 26) quant += 5;

    return type ? &inter_vlcs[rv34_quant_to_vlc_set[1][av_clip(quant, 0, 30)]]

                : &intra_vlcs[rv34_quant_to_vlc_set[0][av_clip(quant, 0, 30)]];

}

/**

 * Decode quantizer difference and return modified quantizer.

 */

static inline int rv34_decode_dquant(GetBitContext *gb, int quant)

{

    if(get_bits1(gb))

        return rv34_dquant_tab[get_bits1(gb)][quant];

    else

        return get_bits(gb, 5);

}

/** @} */ //bitstream functions

/**

 * @defgroup mv motion vector related code (prediction, reconstruction, motion compensation)

 * @{

 */

/** macroblock partition width in 8x8 blocks */

static const uint8_t part_sizes_w[RV34_MB_TYPES] = { 2, 2, 2, 1, 2, 2, 2, 2, 2, 1, 2, 2 };

/** macroblock partition height in 8x8 blocks */

static const uint8_t part_sizes_h[RV34_MB_TYPES] = { 2, 2, 2, 1, 2, 2, 2, 2, 1, 2, 2, 2 };

/** availability index for subblocks */

static const uint8_t avail_indexes[4] = { 6, 7, 10, 11 };

/**

 * motion vector prediction

 *

 * Motion prediction performed for the block by using median prediction of

 * motion vectors from the left, top and right top blocks but in corner cases

 * some other vectors may be used instead.

 */

static void rv34_pred_mv(RV34DecContext *r, int block_type, int subblock_no, int dmv_no)

{

    MpegEncContext *s = &r->s;

    int mv_pos = s->mb_x * 2 + s->mb_y * 2 * s->b8_stride;

    int A[2] = {0}, B[2], C[2];

    int i, j;

    int mx, my;

    int avail_index = avail_indexes[subblock_no];

    int c_off = part_sizes_w[block_type];

    mv_pos += (subblock_no & 1) + (subblock_no >> 1)*s->b8_stride;

    if(subblock_no == 3)

        c_off = -1;

    if(r->avail_cache[avail_index - 1]){

        A[0] = s->current_picture_ptr->motion_val[0][mv_pos-1][0];

        A[1] = s->current_picture_ptr->motion_val[0][mv_pos-1][1];

    }

    if(r->avail_cache[avail_index - 4]){

        B[0] = s->current_picture_ptr->motion_val[0][mv_pos-s->b8_stride][0];

        B[1] = s->current_picture_ptr->motion_val[0][mv_pos-s->b8_stride][1];

    }else{

        B[0] = A[0];

        B[1] = A[1];

    }

    if(!r->avail_cache[avail_index - 4 + c_off]){

        if(r->avail_cache[avail_index - 4] && (r->avail_cache[avail_index - 1] || r->rv30)){

            C[0] = s->current_picture_ptr->motion_val[0][mv_pos-s->b8_stride-1][0];

            C[1] = s->current_picture_ptr->motion_val[0][mv_pos-s->b8_stride-1][1];

        }else{

            C[0] = A[0];

            C[1] = A[1];

        }

    }else{

        C[0] = s->current_picture_ptr->motion_val[0][mv_pos-s->b8_stride+c_off][0];

        C[1] = s->current_picture_ptr->motion_val[0][mv_pos-s->b8_stride+c_off][1];

    }

    mx = mid_pred(A[0], B[0], C[0]);

    my = mid_pred(A[1], B[1], C[1]);

    mx += r->dmv[dmv_no][0];

    my += r->dmv[dmv_no][1];

    for(j = 0; j < part_sizes_h[block_type]; j++){

        for(i = 0; i < part_sizes_w[block_type]; i++){

            s->current_picture_ptr->motion_val[0][mv_pos + i + j*s->b8_stride][0] = mx;

            s->current_picture_ptr->motion_val[0][mv_pos + i + j*s->b8_stride][1] = my;

        }

    }

}

#define GET_PTS_DIFF(a, b) ((a - b + 8192) & 0x1FFF)

/**

 * Calculate motion vector component that should be added for direct blocks.

 */

static int calc_add_mv(RV34DecContext *r, int dir, int val)

{

    int refdist = GET_PTS_DIFF(r->next_pts, r->last_pts);

    int dist = dir ? -GET_PTS_DIFF(r->next_pts, r->cur_pts) : GET_PTS_DIFF(r->cur_pts, r->last_pts);

    int mul;

    if(!refdist) return 0;

    mul = (dist << 14) / refdist;

    return (val * mul + 0x2000) >> 14;

}

/**

 * Predict motion vector for B-frame macroblock.

 */

static inline void rv34_pred_b_vector(int A[2], int B[2], int C[2],

                                      int A_avail, int B_avail, int C_avail,

                                      int *mx, int *my)

{

    if(A_avail + B_avail + C_avail != 3){

        *mx = A[0] + B[0] + C[0];

        *my = A[1] + B[1] + C[1];

        if(A_avail + B_avail + C_avail == 2){

            *mx /= 2;

            *my /= 2;

        }

    }else{

        *mx = mid_pred(A[0], B[0], C[0]);

        *my = mid_pred(A[1], B[1], C[1]);

    }

}

/**

 * motion vector prediction for B-frames

 */

static void rv34_pred_mv_b(RV34DecContext *r, int block_type, int dir)

{

    MpegEncContext *s = &r->s;

    int mb_pos = s->mb_x + s->mb_y * s->mb_stride;

    int mv_pos = s->mb_x * 2 + s->mb_y * 2 * s->b8_stride;

    int A[2], B[2], C[2];

    int has_A = 0, has_B = 0, has_C = 0;

    int mx, my;

    int i, j;

    Picture *cur_pic = s->current_picture_ptr;

    const int mask = dir ? MB_TYPE_L1 : MB_TYPE_L0;

    int type = cur_pic->mb_type[mb_pos];

    memset(A, 0, sizeof(A));

    memset(B, 0, sizeof(B));

    memset(C, 0, sizeof(C));

    if((r->avail_cache[6-1] & type) & mask){

        A[0] = cur_pic->motion_val[dir][mv_pos - 1][0];

        A[1] = cur_pic->motion_val[dir][mv_pos - 1][1];

        has_A = 1;

    }

    if((r->avail_cache[6-4] & type) & mask){

        B[0] = cur_pic->motion_val[dir][mv_pos - s->b8_stride][0];

        B[1] = cur_pic->motion_val[dir][mv_pos - s->b8_stride][1];

        has_B = 1;

    }

    if(r->avail_cache[6-4] && (r->avail_cache[6-2] & type) & mask){

        C[0] = cur_pic->motion_val[dir][mv_pos - s->b8_stride + 2][0];

        C[1] = cur_pic->motion_val[dir][mv_pos - s->b8_stride + 2][1];

        has_C = 1;

    }else if((s->mb_x+1) == s->mb_width && (r->avail_cache[6-5] & type) & mask){

        C[0] = cur_pic->motion_val[dir][mv_pos - s->b8_stride - 1][0];

        C[1] = cur_pic->motion_val[dir][mv_pos - s->b8_stride - 1][1];

        has_C = 1;

    }

    rv34_pred_b_vector(A, B, C, has_A, has_B, has_C, &mx, &my);

    mx += r->dmv[dir][0];

    my += r->dmv[dir][1];

    for(j = 0; j < 2; j++){

        for(i = 0; i < 2; i++){

            cur_pic->motion_val[dir][mv_pos + i + j*s->b8_stride][0] = mx;

            cur_pic->motion_val[dir][mv_pos + i + j*s->b8_stride][1] = my;

        }

    }

    if(block_type == RV34_MB_B_BACKWARD || block_type == RV34_MB_B_FORWARD){

        ZERO8x2(cur_pic->motion_val[!dir][mv_pos], s->b8_stride);

    }

}

/**

 * motion vector prediction - RV3 version

 */

static void rv34_pred_mv_rv3(RV34DecContext *r, int block_type, int dir)

{

    MpegEncContext *s = &r->s;

    int mv_pos = s->mb_x * 2 + s->mb_y * 2 * s->b8_stride;

    int A[2] = {0}, B[2], C[2];

    int i, j, k;

    int mx, my;

    int avail_index = avail_indexes[0];

    if(r->avail_cache[avail_index - 1]){

        A[0] = s->current_picture_ptr->motion_val[0][mv_pos-1][0];

        A[1] = s->current_picture_ptr->motion_val[0][mv_pos-1][1];

    }

    if(r->avail_cache[avail_index - 4]){

        B[0] = s->current_picture_ptr->motion_val[0][mv_pos-s->b8_stride][0];

        B[1] = s->current_picture_ptr->motion_val[0][mv_pos-s->b8_stride][1];

    }else{

        B[0] = A[0];

        B[1] = A[1];

    }

    if(!r->avail_cache[avail_index - 4 + 2]){

        if(r->avail_cache[avail_index - 4] && (r->avail_cache[avail_index - 1])){

            C[0] = s->current_picture_ptr->motion_val[0][mv_pos-s->b8_stride-1][0];

            C[1] = s->current_picture_ptr->motion_val[0][mv_pos-s->b8_stride-1][1];

        }else{

            C[0] = A[0];

            C[1] = A[1];

        }

    }else{

        C[0] = s->current_picture_ptr->motion_val[0][mv_pos-s->b8_stride+2][0];

        C[1] = s->current_picture_ptr->motion_val[0][mv_pos-s->b8_stride+2][1];

    }

    mx = mid_pred(A[0], B[0], C[0]);

    my = mid_pred(A[1], B[1], C[1]);

    mx += r->dmv[0][0];

    my += r->dmv[0][1];

    for(j = 0; j < 2; j++){

        for(i = 0; i < 2; i++){

            for(k = 0; k < 2; k++){

                s->current_picture_ptr->motion_val[k][mv_pos + i + j*s->b8_stride][0] = mx;

                s->current_picture_ptr->motion_val[k][mv_pos + i + j*s->b8_stride][1] = my;

            }

        }

    }

}

static const int chroma_coeffs[3] = { 0, 3, 5 };

/**

 * generic motion compensation function

 *

 * @param r decoder context

 * @param block_type type of the current block

 * @param xoff horizontal offset from the start of the current block

 * @param yoff vertical offset from the start of the current block

 * @param mv_off offset to the motion vector information

 * @param width width of the current partition in 8x8 blocks

 * @param height height of the current partition in 8x8 blocks

 * @param dir motion compensation direction (i.e. from the last or the next reference frame)

 * @param thirdpel motion vectors are specified in 1/3 of pixel

 * @param qpel_mc a set of functions used to perform luma motion compensation

 * @param chroma_mc a set of functions used to perform chroma motion compensation

 */

static inline void rv34_mc(RV34DecContext *r, const int block_type,

                          const int xoff, const int yoff, int mv_off,

                          const int width, const int height, int dir,

                          const int thirdpel,

                          qpel_mc_func (*qpel_mc)[16],

                          h264_chroma_mc_func (*chroma_mc))

{

    MpegEncContext *s = &r->s;

    uint8_t *Y, *U, *V, *srcY, *srcU, *srcV;

    int dxy, mx, my, umx, umy, lx, ly, uvmx, uvmy, src_x, src_y, uvsrc_x, uvsrc_y;

    int mv_pos = s->mb_x * 2 + s->mb_y * 2 * s->b8_stride + mv_off;

    int is16x16 = 1;

    if(thirdpel){

        int chroma_mx, chroma_my;

        mx = (s->current_picture_ptr->motion_val[dir][mv_pos][0] + (3 << 24)) / 3 - (1 << 24);

        my = (s->current_picture_ptr->motion_val[dir][mv_pos][1] + (3 << 24)) / 3 - (1 << 24);

        lx = (s->current_picture_ptr->motion_val[dir][mv_pos][0] + (3 << 24)) % 3;

        ly = (s->current_picture_ptr->motion_val[dir][mv_pos][1] + (3 << 24)) % 3;

        chroma_mx = (s->current_picture_ptr->motion_val[dir][mv_pos][0] + 1) >> 1;

        chroma_my = (s->current_picture_ptr->motion_val[dir][mv_pos][1] + 1) >> 1;

        umx = (chroma_mx + (3 << 24)) / 3 - (1 << 24);

        umy = (chroma_my + (3 << 24)) / 3 - (1 << 24);

        uvmx = chroma_coeffs[(chroma_mx + (3 << 24)) % 3];

        uvmy = chroma_coeffs[(chroma_my + (3 << 24)) % 3];

    }else{

        int cx, cy;

        mx = s->current_picture_ptr->motion_val[dir][mv_pos][0] >> 2;

        my = s->current_picture_ptr->motion_val[dir][mv_pos][1] >> 2;

        lx = s->current_picture_ptr->motion_val[dir][mv_pos][0] & 3;

        ly = s->current_picture_ptr->motion_val[dir][mv_pos][1] & 3;

        cx = s->current_picture_ptr->motion_val[dir][mv_pos][0] / 2;

        cy = s->current_picture_ptr->motion_val[dir][mv_pos][1] / 2;

        umx = cx >> 2;

        umy = cy >> 2;

        uvmx = (cx & 3) << 1;

        uvmy = (cy & 3) << 1;

        //due to some flaw RV40 uses the same MC compensation routine for H2V2 and H3V3

        if(uvmx == 6 && uvmy == 6)

            uvmx = uvmy = 4;

    }

    dxy = ly*4 + lx;

    srcY = dir ? s->next_picture_ptr->data[0] : s->last_picture_ptr->data[0];

    srcU = dir ? s->next_picture_ptr->data[1] : s->last_picture_ptr->data[1];

    srcV = dir ? s->next_picture_ptr->data[2] : s->last_picture_ptr->data[2];

    src_x = s->mb_x * 16 + xoff + mx;

    src_y = s->mb_y * 16 + yoff + my;

    uvsrc_x = s->mb_x * 8 + (xoff >> 1) + umx;

    uvsrc_y = s->mb_y * 8 + (yoff >> 1) + umy;

    srcY += src_y * s->linesize + src_x;

    srcU += uvsrc_y * s->uvlinesize + uvsrc_x;

    srcV += uvsrc_y * s->uvlinesize + uvsrc_x;

    if(   (unsigned)(src_x - !!lx*2) > s->h_edge_pos - !!lx*2 - (width <<3) - 4

       || (unsigned)(src_y - !!ly*2) > s->v_edge_pos - !!ly*2 - (height<<3) - 4){

        uint8_t *uvbuf= s->edge_emu_buffer + 22 * s->linesize;

        srcY -= 2 + 2*s->linesize;

        s->dsp.emulated_edge_mc(s->edge_emu_buffer, srcY, s->linesize, (width<<3)+6, (height<<3)+6,

                            src_x - 2, src_y - 2, s->h_edge_pos, s->v_edge_pos);

        srcY = s->edge_emu_buffer + 2 + 2*s->linesize;

        s->dsp.emulated_edge_mc(uvbuf     , srcU, s->uvlinesize, (width<<2)+1, (height<<2)+1,

                            uvsrc_x, uvsrc_y, s->h_edge_pos >> 1, s->v_edge_pos >> 1);

        s->dsp.emulated_edge_mc(uvbuf + 16, srcV, s->uvlinesize, (width<<2)+1, (height<<2)+1,

                            uvsrc_x, uvsrc_y, s->h_edge_pos >> 1, s->v_edge_pos >> 1);

        srcU = uvbuf;

        srcV = uvbuf + 16;

    }

    Y = s->dest[0] + xoff      + yoff     *s->linesize;

    U = s->dest[1] + (xoff>>1) + (yoff>>1)*s->uvlinesize;

    V = s->dest[2] + (xoff>>1) + (yoff>>1)*s->uvlinesize;

    if(block_type == RV34_MB_P_16x8){

        qpel_mc[1][dxy](Y, srcY, s->linesize);

        Y    += 8;

        srcY += 8;

    }else if(block_type == RV34_MB_P_8x16){

        qpel_mc[1][dxy](Y, srcY, s->linesize);

        Y    += 8 * s->linesize;

        srcY += 8 * s->linesize;

    }

    is16x16 = (block_type != RV34_MB_P_8x8) && (block_type != RV34_MB_P_16x8) && (block_type != RV34_MB_P_8x16);

    qpel_mc[!is16x16][dxy](Y, srcY, s->linesize);

    chroma_mc[2-width]   (U, srcU, s->uvlinesize, height*4, uvmx, uvmy);

    chroma_mc[2-width]   (V, srcV, s->uvlinesize, height*4, uvmx, uvmy);

}

static void rv34_mc_1mv(RV34DecContext *r, const int block_type,

                        const int xoff, const int yoff, int mv_off,

                        const int width, const int height, int dir)

{

    rv34_mc(r, block_type, xoff, yoff, mv_off, width, height, dir, r->rv30,

            r->rv30 ? r->s.dsp.put_rv30_tpel_pixels_tab

                    : r->s.dsp.put_rv40_qpel_pixels_tab,

            r->rv30 ? r->s.dsp.put_h264_chroma_pixels_tab

                    : r->s.dsp.put_rv40_chroma_pixels_tab);

}

static void rv34_mc_2mv(RV34DecContext *r, const int block_type)

{

    rv34_mc(r, block_type, 0, 0, 0, 2, 2, 0, r->rv30,

            r->rv30 ? r->s.dsp.put_rv30_tpel_pixels_tab

                    : r->s.dsp.put_rv40_qpel_pixels_tab,

            r->rv30 ? r->s.dsp.put_h264_chroma_pixels_tab

                    : r->s.dsp.put_rv40_chroma_pixels_tab);

    rv34_mc(r, block_type, 0, 0, 0, 2, 2, 1, r->rv30,

            r->rv30 ? r->s.dsp.avg_rv30_tpel_pixels_tab

                    : r->s.dsp.avg_rv40_qpel_pixels_tab,

            r->rv30 ? r->s.dsp.avg_h264_chroma_pixels_tab

                    : r->s.dsp.avg_rv40_chroma_pixels_tab);

}

static void rv34_mc_2mv_skip(RV34DecContext *r)

{

    int i, j;

    for(j = 0; j < 2; j++)

        for(i = 0; i < 2; i++){

             rv34_mc(r, RV34_MB_P_8x8, i*8, j*8, i+j*r->s.b8_stride, 1, 1, 0, r->rv30,

                    r->rv30 ? r->s.dsp.put_rv30_tpel_pixels_tab

                            : r->s.dsp.put_rv40_qpel_pixels_tab,

                    r->rv30 ? r->s.dsp.put_h264_chroma_pixels_tab

                            : r->s.dsp.put_rv40_chroma_pixels_tab);

             rv34_mc(r, RV34_MB_P_8x8, i*8, j*8, i+j*r->s.b8_stride, 1, 1, 1, r->rv30,

                    r->rv30 ? r->s.dsp.avg_rv30_tpel_pixels_tab

                            : r->s.dsp.avg_rv40_qpel_pixels_tab,

                    r->rv30 ? r->s.dsp.avg_h264_chroma_pixels_tab

                            : r->s.dsp.avg_rv40_chroma_pixels_tab);

        }

}

/** number of motion vectors in each macroblock type */

static const int num_mvs[RV34_MB_TYPES] = { 0, 0, 1, 4, 1, 1, 0, 0, 2, 2, 2, 1 };

/**

 * Decode motion vector differences

 * and perform motion vector reconstruction and motion compensation.

 */

static int rv34_decode_mv(RV34DecContext *r, int block_type)

{

    MpegEncContext *s = &r->s;

    GetBitContext *gb = &s->gb;

    int i, j, k, l;

    int mv_pos = s->mb_x * 2 + s->mb_y * 2 * s->b8_stride;

    int next_bt;

    memset(r->dmv, 0, sizeof(r->dmv));

    for(i = 0; i < num_mvs[block_type]; i++){

        r->dmv[i][0] = svq3_get_se_golomb(gb);

        r->dmv[i][1] = svq3_get_se_golomb(gb);

    }

    switch(block_type){

    case RV34_MB_TYPE_INTRA:

    case RV34_MB_TYPE_INTRA16x16:

        ZERO8x2(s->current_picture_ptr->motion_val[0][s->mb_x * 2 + s->mb_y * 2 * s->b8_stride], s->b8_stride);

        return 0;

    case RV34_MB_SKIP:

        if(s->pict_type == FF_P_TYPE){

            ZERO8x2(s->current_picture_ptr->motion_val[0][s->mb_x * 2 + s->mb_y * 2 * s->b8_stride], s->b8_stride);

            rv34_mc_1mv (r, block_type, 0, 0, 0, 2, 2, 0);

            break;

        }

    case RV34_MB_B_DIRECT:

        //surprisingly, it uses motion scheme from next reference frame

        next_bt = s->next_picture_ptr->mb_type[s->mb_x + s->mb_y * s->mb_stride];

        if(IS_INTRA(next_bt) || IS_SKIP(next_bt)){

            ZERO8x2(s->current_picture_ptr->motion_val[0][s->mb_x * 2 + s->mb_y * 2 * s->b8_stride], s->b8_stride);

            ZERO8x2(s->current_picture_ptr->motion_val[1][s->mb_x * 2 + s->mb_y * 2 * s->b8_stride], s->b8_stride);

        }else

            for(j = 0; j < 2; j++)

                for(i = 0; i < 2; i++)

                    for(k = 0; k < 2; k++)

                        for(l = 0; l < 2; l++)

                            s->current_picture_ptr->motion_val[l][mv_pos + i + j*s->b8_stride][k] = calc_add_mv(r, l, s->next_picture_ptr->motion_val[0][mv_pos + i + j*s->b8_stride][k]);

        if(!(IS_16X8(next_bt) || IS_8X16(next_bt) || IS_8X8(next_bt))) //we can use whole macroblock MC

            rv34_mc_2mv(r, block_type);

        else

            rv34_mc_2mv_skip(r);

        ZERO8x2(s->current_picture_ptr->motion_val[0][s->mb_x * 2 + s->mb_y * 2 * s->b8_stride], s->b8_stride);

        break;

    case RV34_MB_P_16x16:

    case RV34_MB_P_MIX16x16:

        rv34_pred_mv(r, block_type, 0, 0);

        rv34_mc_1mv (r, block_type, 0, 0, 0, 2, 2, 0);

        break;

    case RV34_MB_B_FORWARD:

    case RV34_MB_B_BACKWARD:

        r->dmv[1][0] = r->dmv[0][0];

        r->dmv[1][1] = r->dmv[0][1];

        if(r->rv30)

            rv34_pred_mv_rv3(r, block_type, block_type == RV34_MB_B_BACKWARD);

        else

            rv34_pred_mv_b  (r, block_type, block_type == RV34_MB_B_BACKWARD);

        rv34_mc_1mv     (r, block_type, 0, 0, 0, 2, 2, block_type == RV34_MB_B_BACKWARD);

        break;

    case RV34_MB_P_16x8:

    case RV34_MB_P_8x16:

        rv34_pred_mv(r, block_type, 0, 0);

        rv34_pred_mv(r, block_type, 1 + (block_type == RV34_MB_P_16x8), 1);

        if(block_type == RV34_MB_P_16x8){

            rv34_mc_1mv(r, block_type, 0, 0, 0,            2, 1, 0);

            rv34_mc_1mv(r, block_type, 0, 8, s->b8_stride, 2, 1, 0);

        }

        if(block_type == RV34_MB_P_8x16){

            rv34_mc_1mv(r, block_type, 0, 0, 0, 1, 2, 0);

            rv34_mc_1mv(r, block_type, 8, 0, 1, 1, 2, 0);

        }

        break;

    case RV34_MB_B_BIDIR:

        rv34_pred_mv_b  (r, block_type, 0);

        rv34_pred_mv_b  (r, block_type, 1);

        rv34_mc_2mv     (r, block_type);

        break;

    case RV34_MB_P_8x8:

        for(i=0;i< 4;i++){

            rv34_pred_mv(r, block_type, i, i);

            rv34_mc_1mv (r, block_type, (i&1)<<3, (i&2)<<2, (i&1)+(i>>1)*s->b8_stride, 1, 1, 0);

        }

        break;

    }

    return 0;

}

/** @} */ // mv group

/**

 * @defgroup recons Macroblock reconstruction functions

 * @{

 */

/** mapping of RV30/40 intra prediction types to standard H.264 types */

static const int ittrans[9] = {

 DC_PRED, VERT_PRED, HOR_PRED, DIAG_DOWN_RIGHT_PRED, DIAG_DOWN_LEFT_PRED,

 VERT_RIGHT_PRED, VERT_LEFT_PRED, HOR_UP_PRED, HOR_DOWN_PRED,

};

/** mapping of RV30/40 intra 16x16 prediction types to standard H.264 types */

static const int ittrans16[4] = {

 DC_PRED8x8, VERT_PRED8x8, HOR_PRED8x8, PLANE_PRED8x8,

};

/**

 * Perform 4x4 intra prediction.

 */

static void rv34_pred_4x4_block(RV34DecContext *r, uint8_t *dst, int stride, int itype, int up, int left, int down, int right)

{

    uint8_t *prev = dst - stride + 4;

    uint32_t topleft;

    if(!up && !left)

        itype = DC_128_PRED;

    else if(!up){

        if(itype == VERT_PRED) itype = HOR_PRED;

        if(itype == DC_PRED)   itype = LEFT_DC_PRED;

    }else if(!left){

        if(itype == HOR_PRED)  itype = VERT_PRED;

        if(itype == DC_PRED)   itype = TOP_DC_PRED;

        if(itype == DIAG_DOWN_LEFT_PRED) itype = DIAG_DOWN_LEFT_PRED_RV40_NODOWN;

    }

    if(!down){

        if(itype == DIAG_DOWN_LEFT_PRED) itype = DIAG_DOWN_LEFT_PRED_RV40_NODOWN;

        if(itype == HOR_UP_PRED) itype = HOR_UP_PRED_RV40_NODOWN;

        if(itype == VERT_LEFT_PRED) itype = VERT_LEFT_PRED_RV40_NODOWN;

    }

    if(!right && up){

        topleft = dst[-stride + 3] * 0x01010101;

        prev = (uint8_t*)&topleft;

    }

    r->h.pred4x4[itype](dst, prev, stride);

}

/** add_pixels_clamped for 4x4 block */

static void rv34_add_4x4_block(uint8_t *dst, int stride, DCTELEM block[64], int off)

{

    int x, y;

    for(y = 0; y < 4; y++)

        for(x = 0; x < 4; x++)

            dst[x + y*stride] = av_clip_uint8(dst[x + y*stride] + block[off + x+y*8]);

}

static inline int adjust_pred16(int itype, int up, int left)

{

    if(!up && !left)

        itype = DC_128_PRED8x8;

    else if(!up){

        if(itype == PLANE_PRED8x8)itype = HOR_PRED8x8;

        if(itype == VERT_PRED8x8) itype = HOR_PRED8x8;

        if(itype == DC_PRED8x8)   itype = LEFT_DC_PRED8x8;

    }else if(!left){

        if(itype == PLANE_PRED8x8)itype = VERT_PRED8x8;

        if(itype == HOR_PRED8x8)  itype = VERT_PRED8x8;

        if(itype == DC_PRED8x8)   itype = TOP_DC_PRED8x8;

    }

    return itype;

}

static void rv34_output_macroblock(RV34DecContext *r, int8_t *intra_types, int cbp, int is16)

{

    MpegEncContext *s = &r->s;

    DSPContext *dsp = &s->dsp;

    int i, j;

    uint8_t *Y, *U, *V;

    int itype;

    int avail[6*8] = {0};

    int idx;

    // Set neighbour information.

    if(r->avail_cache[1])

        avail[0] = 1;

    if(r->avail_cache[2])

        avail[1] = avail[2] = 1;

    if(r->avail_cache[3])

        avail[3] = avail[4] = 1;

    if(r->avail_cache[4])

        avail[5] = 1;

    if(r->avail_cache[5])

        avail[8] = avail[16] = 1;

    if(r->avail_cache[9])

        avail[24] = avail[32] = 1;

    Y = s->dest[0];

    U = s->dest[1];

    V = s->dest[2];

    if(!is16){

        for(j = 0; j < 4; j++){

            idx = 9 + j*8;

            for(i = 0; i < 4; i++, cbp >>= 1, Y += 4, idx++){

                rv34_pred_4x4_block(r, Y, s->linesize, ittrans[intra_types[i]], avail[idx-8], avail[idx-1], avail[idx+7], avail[idx-7]);

                avail[idx] = 1;

                if(cbp & 1)

                    rv34_add_4x4_block(Y, s->linesize, s->block[(i>>1)+(j&2)], (i&1)*4+(j&1)*32);

            }

            Y += s->linesize * 4 - 4*4;

            intra_types += r->intra_types_stride;

        }

        intra_types -= r->intra_types_stride * 4;

        fill_rectangle(r->avail_cache + 6, 2, 2, 4, 0, 4);

        for(j = 0; j < 2; j++){

            idx = 6 + j*4;

            for(i = 0; i < 2; i++, cbp >>= 1, idx++){

                rv34_pred_4x4_block(r, U + i*4 + j*4*s->uvlinesize, s->uvlinesize, ittrans[intra_types[i*2+j*2*r->intra_types_stride]], r->avail_cache[idx-4], r->avail_cache[idx-1], !i && !j, r->avail_cache[idx-3]);

                rv34_pred_4x4_block(r, V + i*4 + j*4*s->uvlinesize, s->uvlinesize, ittrans[intra_types[i*2+j*2*r->intra_types_stride]], r->avail_cache[idx-4], r->avail_cache[idx-1], !i && !j, r->avail_cache[idx-3]);

                r->avail_cache[idx] = 1;

                if(cbp & 0x01)

                    rv34_add_4x4_block(U + i*4 + j*4*s->uvlinesize, s->uvlinesize, s->block[4], i*4+j*32);

                if(cbp & 0x10)

                    rv34_add_4x4_block(V + i*4 + j*4*s->uvlinesize, s->uvlinesize, s->block[5], i*4+j*32);

            }

        }

    }else{

        itype = ittrans16[intra_types[0]];

        itype = adjust_pred16(itype, r->avail_cache[6-4], r->avail_cache[6-1]);

        r->h.pred16x16[itype](Y, s->linesize);

        dsp->add_pixels_clamped(s->block[0], Y,     s->linesize);

        dsp->add_pixels_clamped(s->block[1], Y + 8, s->linesize);

        Y += s->linesize * 8;

        dsp->add_pixels_clamped(s->block[2], Y,     s->linesize);

        dsp->add_pixels_clamped(s->block[3], Y + 8, s->linesize);

        itype = ittrans16[intra_types[0]];

        if(itype == PLANE_PRED8x8) itype = DC_PRED8x8;

        itype = adjust_pred16(itype, r->avail_cache[6-4], r->avail_cache[6-1]);

        r->h.pred8x8[itype](U, s->uvlinesize);

        dsp->add_pixels_clamped(s->block[4], U, s->uvlinesize);

        r->h.pred8x8[itype](V, s->uvlinesize);

        dsp->add_pixels_clamped(s->block[5], V, s->uvlinesize);

    }

}

/** @} */ // recons group

/**

 * @addtogroup bitstream

 * Decode macroblock header and return CBP in case of success, -1 otherwise.

 */

static int rv34_decode_mb_header(RV34DecContext *r, int8_t *intra_types)

{

    MpegEncContext *s = &r->s;

    GetBitContext *gb = &s->gb;

    int mb_pos = s->mb_x + s->mb_y * s->mb_stride;

    int i, t;

    if(!r->si.type){

        r->is16 = get_bits1(gb);

        if(!r->is16 && !r->rv30){

            if(!get_bits1(gb))

                av_log(s->avctx, AV_LOG_ERROR, "Need DQUANT\n");

        }

        s->current_picture_ptr->mb_type[mb_pos] = r->is16 ? MB_TYPE_INTRA16x16 : MB_TYPE_INTRA;

        r->block_type = r->is16 ? RV34_MB_TYPE_INTRA16x16 : RV34_MB_TYPE_INTRA;

    }else{

        r->block_type = r->decode_mb_info(r);

        if(r->block_type == -1)

            return -1;

        s->current_picture_ptr->mb_type[mb_pos] = rv34_mb_type_to_lavc[r->block_type];

        r->mb_type[mb_pos] = r->block_type;

        if(r->block_type == RV34_MB_SKIP){

            if(s->pict_type == FF_P_TYPE)

                r->mb_type[mb_pos] = RV34_MB_P_16x16;

            if(s->pict_type == FF_B_TYPE)

                r->mb_type[mb_pos] = RV34_MB_B_DIRECT;

        }

        r->is16 = !!IS_INTRA16x16(s->current_picture_ptr->mb_type[mb_pos]);

        rv34_decode_mv(r, r->block_type);

        if(r->block_type == RV34_MB_SKIP){

            fill_rectangle(intra_types, 4, 4, r->intra_types_stride, 0, sizeof(intra_types[0]));

            return 0;

        }

        r->chroma_vlc = 1;

        r->luma_vlc   = 0;

    }

    if(IS_INTRA(s->current_picture_ptr->mb_type[mb_pos])){

        if(r->is16){

            t = get_bits(gb, 2);

            fill_rectangle(intra_types, 4, 4, r->intra_types_stride, t, sizeof(intra_types[0]));

            r->luma_vlc   = 2;

        }else{

            if(r->decode_intra_types(r, gb, intra_types) < 0)

                return -1;

            r->luma_vlc   = 1;

        }

        r->chroma_vlc = 0;

        r->cur_vlcs = choose_vlc_set(r->si.quant, r->si.vlc_set, 0);

    }else{

        for(i = 0; i < 16; i++)

            intra_types[(i & 3) + (i>>2) * r->intra_types_stride] = 0;

        r->cur_vlcs = choose_vlc_set(r->si.quant, r->si.vlc_set, 1);

        if(r->mb_type[mb_pos] == RV34_MB_P_MIX16x16){

            r->is16 = 1;

            r->chroma_vlc = 1;

            r->luma_vlc   = 2;

            r->cur_vlcs = choose_vlc_set(r->si.quant, r->si.vlc_set, 0);

        }

    }

    return rv34_decode_cbp(gb, r->cur_vlcs, r->is16);

}

/**

 * @addtogroup recons

 * @{

 */

/**

 * mask for retrieving all bits in coded block pattern

 * corresponding to one 8x8 block

 */

#define LUMA_CBP_BLOCK_MASK 0x33

#define U_CBP_MASK 0x0F0000

#define V_CBP_MASK 0xF00000

static void rv34_apply_differences(RV34DecContext *r, int cbp)

{

    static const int shifts[4] = { 0, 2, 8, 10 };

    MpegEncContext *s = &r->s;

    int i;

    for(i = 0; i < 4; i++)

        if((cbp & (LUMA_CBP_BLOCK_MASK << shifts[i])) || r->block_type == RV34_MB_P_MIX16x16)

            s->dsp.add_pixels_clamped(s->block[i], s->dest[0] + (i & 1)*8 + (i&2)*4*s->linesize, s->linesize);

    if(cbp & U_CBP_MASK)

        s->dsp.add_pixels_clamped(s->block[4], s->dest[1], s->uvlinesize);

    if(cbp & V_CBP_MASK)

        s->dsp.add_pixels_clamped(s->block[5], s->dest[2], s->uvlinesize);

}

static int is_mv_diff_gt_3(int16_t (*motion_val)[2], int step)

{

    int d;

    d = motion_val[0][0] - motion_val[-step][0];

    if(d < -3 || d > 3)

        return 1;

    d = motion_val[0][1] - motion_val[-step][1];

    if(d < -3 || d > 3)

        return 1;

    return 0;

}

static int rv34_set_deblock_coef(RV34DecContext *r)

{

    MpegEncContext *s = &r->s;

    int hmvmask = 0, vmvmask = 0, i, j;

    int midx = s->mb_x * 2 + s->mb_y * 2 * s->b8_stride;

    int16_t (*motion_val)[2] = &s->current_picture_ptr->motion_val[0][midx];

    for(j = 0; j < 16; j += 8){

        for(i = 0; i < 2; i++){

            if(is_mv_diff_gt_3(motion_val + i, 1))

                vmvmask |= 0x11 << (j + i*2);

            if((j || s->mb_y) && is_mv_diff_gt_3(motion_val + i, s->b8_stride))

                hmvmask |= 0x03 << (j + i*2);

        }

        motion_val += s->b8_stride;

    }

    if(s->first_slice_line)

        hmvmask &= ~0x000F;

    if(!s->mb_x)

        vmvmask &= ~0x1111;

    if(r->rv30){ //RV30 marks both subblocks on the edge for filtering

        vmvmask |= (vmvmask & 0x4444) >> 1;

        hmvmask |= (hmvmask & 0x0F00) >> 4;

        if(s->mb_x)

            r->deblock_coefs[s->mb_x - 1 + s->mb_y*s->mb_stride] |= (vmvmask & 0x1111) << 3;

        if(!s->first_slice_line)

            r->deblock_coefs[s->mb_x + (s->mb_y - 1)*s->mb_stride] |= (hmvmask & 0xF) << 12;

    }

    return hmvmask | vmvmask;

}

static int rv34_decode_macroblock(RV34DecContext *r, int8_t *intra_types)

{

    MpegEncContext *s = &r->s;

    GetBitContext *gb = &s->gb;

    int cbp, cbp2;

    int i, blknum, blkoff;

    DCTELEM block16[64];

    int luma_dc_quant;

    int dist;

    int mb_pos = s->mb_x + s->mb_y * s->mb_stride;

    // Calculate which neighbours are available. Maybe it's worth optimizing too.

    memset(r->avail_cache, 0, sizeof(r->avail_cache));

    fill_rectangle(r->avail_cache + 6, 2, 2, 4, 1, 4);

    dist = (s->mb_x - s->resync_mb_x) + (s->mb_y - s->resync_mb_y) * s->mb_width;

    if(s->mb_x && dist)

        r->avail_cache[5] =

        r->avail_cache[9] = s->current_picture_ptr->mb_type[mb_pos - 1];

    if(dist >= s->mb_width)

        r->avail_cache[2] =

        r->avail_cache[3] = s->current_picture_ptr->mb_type[mb_pos - s->mb_stride];

    if(((s->mb_x+1) < s->mb_width) && dist >= s->mb_width - 1)

        r->avail_cache[4] = s->current_picture_ptr->mb_type[mb_pos - s->mb_stride + 1];

    if(s->mb_x && dist > s->mb_width)

        r->avail_cache[1] = s->current_picture_ptr->mb_type[mb_pos - s->mb_stride - 1];