h263.c

从FFMPEG转换而来的H264解码程序,VC下编译..

                if(s->dquant)
                    put_bits(pb2, 2, dquant_code[s->dquant+2]);

                assert(!s->progressive_sequence);
                if(cbp)
                    put_bits(pb2, 1, s->interlaced_dct);
                put_bits(pb2, 1, 1);

                if(interleaved_stats){
                    s->misc_bits+= get_bits_diff(s);
                }

                /* motion vectors: 16x8 interlaced mode */
                h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
                pred_y /=2;

                put_bits(&s->pb, 1, s->field_select[0][0]);
                put_bits(&s->pb, 1, s->field_select[0][1]);

                ff_h263_encode_motion_vector(s, s->mv[0][0][0] - pred_x,
                                                s->mv[0][0][1] - pred_y, s->f_code);
                ff_h263_encode_motion_vector(s, s->mv[0][1][0] - pred_x,
                                                s->mv[0][1][1] - pred_y, s->f_code);
            }else{
                assert(s->mv_type==MV_TYPE_8X8);
                put_bits(&s->pb,
                        inter_MCBPC_bits[cbpc+16],
                        inter_MCBPC_code[cbpc+16]);
                put_bits(pb2, cbpy_tab[cbpy][1], cbpy_tab[cbpy][0]);

                if(!s->progressive_sequence){
                    if(cbp)
                        put_bits(pb2, 1, s->interlaced_dct);
                }

                if(interleaved_stats){
                    s->misc_bits+= get_bits_diff(s);
                }

                for(i=0; i<4; i++){
                    /* motion vectors: 8x8 mode*/
                    h263_pred_motion(s, i, 0, &pred_x, &pred_y);

                    ff_h263_encode_motion_vector(s, s->current_picture.motion_val[0][ s->block_index[i] ][0] - pred_x,
                                                    s->current_picture.motion_val[0][ s->block_index[i] ][1] - pred_y, s->f_code);
                }
            }

            if(interleaved_stats){
                s->mv_bits+= get_bits_diff(s);
            }

            mpeg4_encode_blocks(s, block, NULL, NULL, NULL, tex_pb);

            if(interleaved_stats){
                s->p_tex_bits+= get_bits_diff(s);
            }
            s->f_count++;
        }
    } else {
        int cbp;
        int dc_diff[6];   //dc values with the dc prediction subtracted
        int dir[6];  //prediction direction
        int zigzag_last_index[6];
        uint8_t *scan_table[6];
        int i;

        for(i=0; i<6; i++){
            dc_diff[i]= ff_mpeg4_pred_dc(s, i, block[i][0], &dir[i], 1);
        }

        if(s->flags & CODEC_FLAG_AC_PRED){
            s->ac_pred= decide_ac_pred(s, block, dir, scan_table, zigzag_last_index);
            if(!s->ac_pred)
                restore_ac_coeffs(s, block, dir, scan_table, zigzag_last_index);
        }else{
            for(i=0; i<6; i++)
                scan_table[i]= s->intra_scantable.permutated;
        }

        /* compute cbp */
        cbp = 0;
        for (i = 0; i < 6; i++) {
            if (s->block_last_index[i] >= 1)
                cbp |= 1 << (5 - i);
        }

        cbpc = cbp & 3;
        if (s->pict_type == I_TYPE) {
            if(s->dquant) cbpc+=4;
            put_bits(&s->pb,
                intra_MCBPC_bits[cbpc],
                intra_MCBPC_code[cbpc]);
        } else {
            if(s->dquant) cbpc+=8;
            put_bits(&s->pb, 1, 0);     /* mb coded */
            put_bits(&s->pb,
                inter_MCBPC_bits[cbpc + 4],
                inter_MCBPC_code[cbpc + 4]);
        }
        put_bits(pb2, 1, s->ac_pred);
        cbpy = cbp >> 2;
        put_bits(pb2, cbpy_tab[cbpy][1], cbpy_tab[cbpy][0]);
        if(s->dquant)
            put_bits(dc_pb, 2, dquant_code[s->dquant+2]);

        if(!s->progressive_sequence){
            put_bits(dc_pb, 1, s->interlaced_dct);
        }

        if(interleaved_stats){
            s->misc_bits+= get_bits_diff(s);
        }

        mpeg4_encode_blocks(s, block, dc_diff, scan_table, dc_pb, tex_pb);

        if(interleaved_stats){
            s->i_tex_bits+= get_bits_diff(s);
        }
        s->i_count++;

        /* restore ac coeffs & last_index stuff if we messed them up with the prediction */
        if(s->ac_pred)
            restore_ac_coeffs(s, block, dir, scan_table, zigzag_last_index);
    }
}

void h263_encode_mb(MpegEncContext * s,
                    DCTELEM block[6][64],
                    int motion_x, int motion_y)
{
    int cbpc, cbpy, i, cbp, pred_x, pred_y;
    int16_t pred_dc;
    int16_t rec_intradc[6];
    int16_t *dc_ptr[6];
    const int interleaved_stats= (s->flags&CODEC_FLAG_PASS1);
    const int dquant_code[5]= {1,0,9,2,3};

    //printf("**mb x=%d y=%d\n", s->mb_x, s->mb_y);
    if (!s->mb_intra) {
        /* compute cbp */
        cbp= get_p_cbp(s, block, motion_x, motion_y);

        if ((cbp | motion_x | motion_y | s->dquant | (s->mv_type - MV_TYPE_16X16)) == 0) {
            /* skip macroblock */
            put_bits(&s->pb, 1, 1);
            if(interleaved_stats){
                s->misc_bits++;
                s->last_bits++;
            }
            s->skip_count++;

            return;
        }
        put_bits(&s->pb, 1, 0);         /* mb coded */

        cbpc = cbp & 3;
        cbpy = cbp >> 2;
        if(s->alt_inter_vlc==0 || cbpc!=3)
            cbpy ^= 0xF;
        if(s->dquant) cbpc+= 8;
        if(s->mv_type==MV_TYPE_16X16){
            put_bits(&s->pb,
                    inter_MCBPC_bits[cbpc],
                    inter_MCBPC_code[cbpc]);

            put_bits(&s->pb, cbpy_tab[cbpy][1], cbpy_tab[cbpy][0]);
            if(s->dquant)
                put_bits(&s->pb, 2, dquant_code[s->dquant+2]);

            if(interleaved_stats){
                s->misc_bits+= get_bits_diff(s);
            }

            /* motion vectors: 16x16 mode */
            h263_pred_motion(s, 0, 0, &pred_x, &pred_y);

            if (!s->umvplus) {
                ff_h263_encode_motion_vector(s, motion_x - pred_x,
                                                motion_y - pred_y, 1);
            }
            else {
                h263p_encode_umotion(s, motion_x - pred_x);
                h263p_encode_umotion(s, motion_y - pred_y);
                if (((motion_x - pred_x) == 1) && ((motion_y - pred_y) == 1))
                    /* To prevent Start Code emulation */
                    put_bits(&s->pb,1,1);
            }
        }else{
            put_bits(&s->pb,
                    inter_MCBPC_bits[cbpc+16],
                    inter_MCBPC_code[cbpc+16]);
            put_bits(&s->pb, cbpy_tab[cbpy][1], cbpy_tab[cbpy][0]);
            if(s->dquant)
                put_bits(&s->pb, 2, dquant_code[s->dquant+2]);

            if(interleaved_stats){
                s->misc_bits+= get_bits_diff(s);
            }

            for(i=0; i<4; i++){
                /* motion vectors: 8x8 mode*/
                h263_pred_motion(s, i, 0, &pred_x, &pred_y);

                motion_x= s->current_picture.motion_val[0][ s->block_index[i] ][0];
                motion_y= s->current_picture.motion_val[0][ s->block_index[i] ][1];
                if (!s->umvplus) {
                    ff_h263_encode_motion_vector(s, motion_x - pred_x,
                                                    motion_y - pred_y, 1);
                }
                else {
                    h263p_encode_umotion(s, motion_x - pred_x);
                    h263p_encode_umotion(s, motion_y - pred_y);
                    if (((motion_x - pred_x) == 1) && ((motion_y - pred_y) == 1))
                        /* To prevent Start Code emulation */
                        put_bits(&s->pb,1,1);
                }
            }
        }

        if(interleaved_stats){
            s->mv_bits+= get_bits_diff(s);
        }
    } else {
        assert(s->mb_intra);

        cbp = 0;
        if (s->h263_aic) {
            /* Predict DC */
            for(i=0; i<6; i++) {
                int16_t level = block[i][0];
                int scale;

                if(i<4) scale= s->y_dc_scale;
                else    scale= s->c_dc_scale;

                pred_dc = h263_pred_dc(s, i, &dc_ptr[i]);
                level -= pred_dc;
                /* Quant */
                if (level >= 0)
                    level = (level + (scale>>1))/scale;
                else
                    level = (level - (scale>>1))/scale;

                /* AIC can change CBP */
                if (level == 0 && s->block_last_index[i] == 0)
                    s->block_last_index[i] = -1;

                if(!s->modified_quant){
                    if (level < -127)
                        level = -127;
                    else if (level > 127)
                        level = 127;
                }

                block[i][0] = level;
                /* Reconstruction */
                rec_intradc[i] = scale*level + pred_dc;
                /* Oddify */
                rec_intradc[i] |= 1;
                //if ((rec_intradc[i] % 2) == 0)
                //    rec_intradc[i]++;
                /* Clipping */
                if (rec_intradc[i] < 0)
                    rec_intradc[i] = 0;
                else if (rec_intradc[i] > 2047)
                    rec_intradc[i] = 2047;

                /* Update AC/DC tables */
                *dc_ptr[i] = rec_intradc[i];
                if (s->block_last_index[i] >= 0)
                    cbp |= 1 << (5 - i);
            }
        }else{
            for(i=0; i<6; i++) {
                /* compute cbp */
                if (s->block_last_index[i] >= 1)
                    cbp |= 1 << (5 - i);
            }
        }

        cbpc = cbp & 3;
        if (s->pict_type == I_TYPE) {
            if(s->dquant) cbpc+=4;
            put_bits(&s->pb,
                intra_MCBPC_bits[cbpc],
                intra_MCBPC_code[cbpc]);
        } else {
            if(s->dquant) cbpc+=8;
            put_bits(&s->pb, 1, 0);     /* mb coded */
            put_bits(&s->pb,
                inter_MCBPC_bits[cbpc + 4],
                inter_MCBPC_code[cbpc + 4]);
        }
        if (s->h263_aic) {
            /* XXX: currently, we do not try to use ac prediction */
            put_bits(&s->pb, 1, 0);     /* no AC prediction */
        }
        cbpy = cbp >> 2;
        put_bits(&s->pb, cbpy_tab[cbpy][1], cbpy_tab[cbpy][0]);
        if(s->dquant)
            put_bits(&s->pb, 2, dquant_code[s->dquant+2]);

        if(interleaved_stats){
            s->misc_bits+= get_bits_diff(s);
        }
    }

    for(i=0; i<6; i++) {
        /* encode each block */
        h263_encode_block(s, block[i], i);

        /* Update INTRADC for decoding */
        if (s->h263_aic && s->mb_intra) {
            block[i][0] = rec_intradc[i];

        }
    }

    if(interleaved_stats){
        if (!s->mb_intra) {
            s->p_tex_bits+= get_bits_diff(s);
            s->f_count++;
        }else{
            s->i_tex_bits+= get_bits_diff(s);
            s->i_count++;
        }
    }
}
#endif

void ff_h263_loop_filter(MpegEncContext * s){
    int qp_c;
    const int linesize  = s->linesize;
    const int uvlinesize= s->uvlinesize;
    const int xy = s->mb_y * s->mb_stride + s->mb_x;
    uint8_t *dest_y = s->dest[0];
    uint8_t *dest_cb= s->dest[1];
    uint8_t *dest_cr= s->dest[2];

//    if(s->pict_type==B_TYPE && !s->readable) return;

    /*
       Diag Top
       Left Center
    */
    if(!IS_SKIP(s->current_picture.mb_type[xy])){
        qp_c= s->qscale;
        s->dsp.h263_v_loop_filter(dest_y+8*linesize  , linesize, qp_c);
        s->dsp.h263_v_loop_filter(dest_y+8*linesize+8, linesize, qp_c);
    }else
        qp_c= 0;

    if(s->mb_y){
        int qp_dt, qp_t, qp_tc;

        if(IS_SKIP(s->current_picture.mb_type[xy-s->mb_stride]))
            qp_t=0;
        else
            qp_t= s->current_picture.qscale_table[xy-s->mb_stride];

        if(qp_c)
            qp_tc= qp_c;
        else
            qp_tc= qp_t;

        if(qp_tc){
            const int chroma_qp= s->chroma_qscale_table[qp_tc];
            s->dsp.h263_v_loop_filter(dest_y  ,   linesize, qp_tc);
            s->dsp.h263_v_loop_filter(dest_y+8,   linesize, qp_tc);

            s->dsp.h263_v_loop_filter(dest_cb , uvlinesize, chroma_qp);