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📄 wmv2.c

📁 从FFMPEG转换而来的H264解码程序,VC下编译..
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/*
 * Copyright (c) 2002 The FFmpeg Project.
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg 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.
 *
 * FFmpeg 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 FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 *
 */

/**
 * @file wmv2.c
 * wmv2 codec.
 */

#include "simple_idct.h"

#define SKIP_TYPE_NONE 0
#define SKIP_TYPE_MPEG 1
#define SKIP_TYPE_ROW  2
#define SKIP_TYPE_COL  3


typedef struct Wmv2Context{
    MpegEncContext s;
    int j_type_bit;
    int j_type;
    int abt_flag;
    int abt_type;
    int abt_type_table[6];
    int per_mb_abt;
    int per_block_abt;
    int mspel_bit;
    int cbp_table_index;
    int top_left_mv_flag;
    int per_mb_rl_bit;
    int skip_type;
    int hshift;

    ScanTable abt_scantable[2];
    DECLARE_ALIGNED_8(DCTELEM, abt_block2[6][64]);
}Wmv2Context;

static void wmv2_common_init(Wmv2Context * w){
    MpegEncContext * const s= &w->s;

    ff_init_scantable(s->dsp.idct_permutation, &w->abt_scantable[0], wmv2_scantableA);
    ff_init_scantable(s->dsp.idct_permutation, &w->abt_scantable[1], wmv2_scantableB);
}

#ifdef CONFIG_ENCODERS

static int encode_ext_header(Wmv2Context *w){
    MpegEncContext * const s= &w->s;
    PutBitContext pb;
    int code;

    init_put_bits(&pb, s->avctx->extradata, s->avctx->extradata_size);

    put_bits(&pb, 5, s->avctx->time_base.den / s->avctx->time_base.num); //yes 29.97 -> 29
    put_bits(&pb, 11, FFMIN(s->bit_rate/1024, 2047));

    put_bits(&pb, 1, w->mspel_bit=1);
    put_bits(&pb, 1, s->loop_filter);
    put_bits(&pb, 1, w->abt_flag=1);
    put_bits(&pb, 1, w->j_type_bit=1);
    put_bits(&pb, 1, w->top_left_mv_flag=0);
    put_bits(&pb, 1, w->per_mb_rl_bit=1);
    put_bits(&pb, 3, code=1);

    flush_put_bits(&pb);

    s->slice_height = s->mb_height / code;

    return 0;
}

static int wmv2_encode_init(AVCodecContext *avctx){
    Wmv2Context * const w= avctx->priv_data;

    if(MPV_encode_init(avctx) < 0)
        return -1;

    wmv2_common_init(w);

    avctx->extradata_size= 4;
    avctx->extradata= av_mallocz(avctx->extradata_size + 10);
    encode_ext_header(w);

    return 0;
}

#if 0 /* unused, remove? */
static int wmv2_encode_end(AVCodecContext *avctx){

    if(MPV_encode_end(avctx) < 0)
        return -1;

    avctx->extradata_size= 0;
    av_freep(&avctx->extradata);

    return 0;
}
#endif

int ff_wmv2_encode_picture_header(MpegEncContext * s, int picture_number)
{
    Wmv2Context * const w= (Wmv2Context*)s;

    put_bits(&s->pb, 1, s->pict_type - 1);
    if(s->pict_type == I_TYPE){
        put_bits(&s->pb, 7, 0);
    }
    put_bits(&s->pb, 5, s->qscale);

    s->dc_table_index = 1;
    s->mv_table_index = 1; /* only if P frame */
//    s->use_skip_mb_code = 1; /* only if P frame */
    s->per_mb_rl_table = 0;
    s->mspel= 0;
    w->per_mb_abt=0;
    w->abt_type=0;
    w->j_type=0;

    assert(s->flipflop_rounding);

    if (s->pict_type == I_TYPE) {
        assert(s->no_rounding==1);
        if(w->j_type_bit) put_bits(&s->pb, 1, w->j_type);

        if(w->per_mb_rl_bit) put_bits(&s->pb, 1, s->per_mb_rl_table);

        if(!s->per_mb_rl_table){
            ff_code012(&s->pb, s->rl_chroma_table_index);
            ff_code012(&s->pb, s->rl_table_index);
        }

        put_bits(&s->pb, 1, s->dc_table_index);

        s->inter_intra_pred= 0;
    }else{
        int cbp_index;

        put_bits(&s->pb, 2, SKIP_TYPE_NONE);

        ff_code012(&s->pb, cbp_index=0);
        if(s->qscale <= 10){
            int map[3]= {0,2,1};
            w->cbp_table_index= map[cbp_index];
        }else if(s->qscale <= 20){
            int map[3]= {1,0,2};
            w->cbp_table_index= map[cbp_index];
        }else{
            int map[3]= {2,1,0};
            w->cbp_table_index= map[cbp_index];
        }

        if(w->mspel_bit) put_bits(&s->pb, 1, s->mspel);

        if(w->abt_flag){
            put_bits(&s->pb, 1, w->per_mb_abt^1);
            if(!w->per_mb_abt){
                ff_code012(&s->pb, w->abt_type);
            }
        }

        if(w->per_mb_rl_bit) put_bits(&s->pb, 1, s->per_mb_rl_table);

        if(!s->per_mb_rl_table){
            ff_code012(&s->pb, s->rl_table_index);
            s->rl_chroma_table_index = s->rl_table_index;
        }
        put_bits(&s->pb, 1, s->dc_table_index);
        put_bits(&s->pb, 1, s->mv_table_index);

        s->inter_intra_pred= 0;//(s->width*s->height < 320*240 && s->bit_rate<=II_BITRATE);
    }
    s->esc3_level_length= 0;
    s->esc3_run_length= 0;

    return 0;
}

/* Nearly identical to wmv1 but that is just because we do not use the
 * useless M$ crap features. It is duplicated here in case someone wants
 * to add support for these crap features. */
void ff_wmv2_encode_mb(MpegEncContext * s,
                       DCTELEM block[6][64],
                       int motion_x, int motion_y)
{
    Wmv2Context * const w= (Wmv2Context*)s;
    int cbp, coded_cbp, i;
    int pred_x, pred_y;
    uint8_t *coded_block;

    handle_slices(s);

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

        put_bits(&s->pb,
                 wmv2_inter_table[w->cbp_table_index][cbp + 64][1],
                 wmv2_inter_table[w->cbp_table_index][cbp + 64][0]);

        /* motion vector */
        h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
        msmpeg4_encode_motion(s, motion_x - pred_x,
                              motion_y - pred_y);
    } else {
        /* compute cbp */
        cbp = 0;
        coded_cbp = 0;
        for (i = 0; i < 6; i++) {
            int val, pred;
            val = (s->block_last_index[i] >= 1);
            cbp |= val << (5 - i);
            if (i < 4) {
                /* predict value for close blocks only for luma */
                pred = coded_block_pred(s, i, &coded_block);
                *coded_block = val;
                val = val ^ pred;
            }
            coded_cbp |= val << (5 - i);
        }
#if 0
        if (coded_cbp)
            printf("cbp=%x %x\n", cbp, coded_cbp);
#endif

        if (s->pict_type == I_TYPE) {
            put_bits(&s->pb,
                     ff_msmp4_mb_i_table[coded_cbp][1], ff_msmp4_mb_i_table[coded_cbp][0]);
        } else {
            put_bits(&s->pb,
                     wmv2_inter_table[w->cbp_table_index][cbp][1],
                     wmv2_inter_table[w->cbp_table_index][cbp][0]);
        }
        put_bits(&s->pb, 1, 0);         /* no AC prediction yet */
        if(s->inter_intra_pred){
            s->h263_aic_dir=0;
            put_bits(&s->pb, table_inter_intra[s->h263_aic_dir][1], table_inter_intra[s->h263_aic_dir][0]);
        }
    }

    for (i = 0; i < 6; i++) {
        ff_msmpeg4_encode_block(s, block[i], i);
    }
}
#endif //CONFIG_ENCODERS

static void parse_mb_skip(Wmv2Context * w){
    int mb_x, mb_y;
    MpegEncContext * const s= &w->s;
    uint32_t * const mb_type= s->current_picture_ptr->mb_type;

    w->skip_type= get_bits(&s->gb, 2);
    switch(w->skip_type){
    case SKIP_TYPE_NONE:
        for(mb_y=0; mb_y<s->mb_height; mb_y++){
            for(mb_x=0; mb_x<s->mb_width; mb_x++){
                mb_type[mb_y*s->mb_stride + mb_x]= MB_TYPE_16x16 | MB_TYPE_L0;
            }
        }
        break;
    case SKIP_TYPE_MPEG:
        for(mb_y=0; mb_y<s->mb_height; mb_y++){
            for(mb_x=0; mb_x<s->mb_width; mb_x++){
                mb_type[mb_y*s->mb_stride + mb_x]= (get_bits1(&s->gb) ? MB_TYPE_SKIP : 0) | MB_TYPE_16x16 | MB_TYPE_L0;
            }
        }
        break;
    case SKIP_TYPE_ROW:
        for(mb_y=0; mb_y<s->mb_height; mb_y++){
            if(get_bits1(&s->gb)){
                for(mb_x=0; mb_x<s->mb_width; mb_x++){
                    mb_type[mb_y*s->mb_stride + mb_x]=  MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
                }
            }else{
                for(mb_x=0; mb_x<s->mb_width; mb_x++){
                    mb_type[mb_y*s->mb_stride + mb_x]= (get_bits1(&s->gb) ? MB_TYPE_SKIP : 0) | MB_TYPE_16x16 | MB_TYPE_L0;
                }
            }
        }
        break;
    case SKIP_TYPE_COL:
        for(mb_x=0; mb_x<s->mb_width; mb_x++){
            if(get_bits1(&s->gb)){
                for(mb_y=0; mb_y<s->mb_height; mb_y++){
                    mb_type[mb_y*s->mb_stride + mb_x]=  MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
                }
            }else{
                for(mb_y=0; mb_y<s->mb_height; mb_y++){
                    mb_type[mb_y*s->mb_stride + mb_x]= (get_bits1(&s->gb) ? MB_TYPE_SKIP : 0) | MB_TYPE_16x16 | MB_TYPE_L0;
                }
            }
        }
        break;
    }
}

static int decode_ext_header(Wmv2Context *w){
    MpegEncContext * const s= &w->s;
    GetBitContext gb;
    int fps;
    int code;

    if(s->avctx->extradata_size<4) return -1;

    init_get_bits(&gb, s->avctx->extradata, s->avctx->extradata_size*8);

    fps                = get_bits(&gb, 5);
    s->bit_rate        = get_bits(&gb, 11)*1024;
    w->mspel_bit       = get_bits1(&gb);
    s->loop_filter     = get_bits1(&gb);
    w->abt_flag        = get_bits1(&gb);
    w->j_type_bit      = get_bits1(&gb);
    w->top_left_mv_flag= get_bits1(&gb);
    w->per_mb_rl_bit   = get_bits1(&gb);
    code               = get_bits(&gb, 3);

    if(code==0) return -1;

    s->slice_height = s->mb_height / code;

    if(s->avctx->debug&FF_DEBUG_PICT_INFO){
        av_log(s->avctx, AV_LOG_DEBUG, "fps:%d, br:%d, qpbit:%d, abt_flag:%d, j_type_bit:%d, tl_mv_flag:%d, mbrl_bit:%d, code:%d, loop_filter:%d, slices:%d\n",
        fps, s->bit_rate, w->mspel_bit, w->abt_flag, w->j_type_bit, w->top_left_mv_flag, w->per_mb_rl_bit, code, s->loop_filter,
        code);
    }
    return 0;
}

int ff_wmv2_decode_picture_header(MpegEncContext * s)
{
    Wmv2Context * const w= (Wmv2Context*)s;
    int code;

#if 0
{
int i;
for(i=0; i<s->gb.size*8; i++)
    printf("%d", get_bits1(&s->gb));
//    get_bits1(&s->gb);
printf("END\n");
return -1;
}
#endif
    if(s->picture_number==0)
        decode_ext_header(w);

    s->pict_type = get_bits(&s->gb, 1) + 1;
    if(s->pict_type == I_TYPE){
        code = get_bits(&s->gb, 7);
        av_log(s->avctx, AV_LOG_DEBUG, "I7:%X/\n", code);
    }
    s->chroma_qscale= s->qscale = get_bits(&s->gb, 5);
    if(s->qscale < 0)
       return -1;

    return 0;
}

int ff_wmv2_decode_secondary_picture_header(MpegEncContext * s)
{
    Wmv2Context * const w= (Wmv2Context*)s;

    if (s->pict_type == I_TYPE) {
        if(w->j_type_bit) w->j_type= get_bits1(&s->gb);
        else              w->j_type= 0; //FIXME check

        if(!w->j_type){
            if(w->per_mb_rl_bit) s->per_mb_rl_table= get_bits1(&s->gb);
            else                 s->per_mb_rl_table= 0;

            if(!s->per_mb_rl_table){
                s->rl_chroma_table_index = decode012(&s->gb);
                s->rl_table_index = decode012(&s->gb);
            }

            s->dc_table_index = get_bits1(&s->gb);
        }
        s->inter_intra_pred= 0;
        s->no_rounding = 1;
        if(s->avctx->debug&FF_DEBUG_PICT_INFO){
            av_log(s->avctx, AV_LOG_DEBUG, "qscale:%d rlc:%d rl:%d dc:%d mbrl:%d j_type:%d \n",
                s->qscale,
                s->rl_chroma_table_index,
                s->rl_table_index,
                s->dc_table_index,
                s->per_mb_rl_table,
                w->j_type);
        }
    }else{
        int cbp_index;
        w->j_type=0;

        parse_mb_skip(w);
        cbp_index= decode012(&s->gb);
        if(s->qscale <= 10){
            int map[3]= {0,2,1};
            w->cbp_table_index= map[cbp_index];
        }else if(s->qscale <= 20){
            int map[3]= {1,0,2};
            w->cbp_table_index= map[cbp_index];
        }else{
            int map[3]= {2,1,0};
            w->cbp_table_index= map[cbp_index];
        }

        if(w->mspel_bit) s->mspel= get_bits1(&s->gb);
        else             s->mspel= 0; //FIXME check

        if(w->abt_flag){
            w->per_mb_abt= get_bits1(&s->gb)^1;
            if(!w->per_mb_abt){
                w->abt_type= decode012(&s->gb);

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