mpeg12.c

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/*
 * MPEG1/2 decoder
 * Copyright (c) 2000,2001 Fabrice Bellard.
 * Copyright (c) 2002-2004 Michael Niedermayer <[e-mail]>
 *
 * 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 mpeg12.c
 * MPEG1/2 decoder
 */

//#define DEBUG
#include "avcodec.h"
#include "dsputil.h"
#include "mpegvideo.h"

#include "mpeg12.h"
#include "mpeg12data.h"
#include "mpeg12decdata.h"
#include "bytestream.h"
#undef memcpy
#define memcpy uc_memcpy
//#undef NDEBUG
//#include <assert.h>


#define DC_VLC_BITS 9
#define MV_VLC_BITS 9
#define MBINCR_VLC_BITS 9
#define MB_PAT_VLC_BITS 9
#define MB_PTYPE_VLC_BITS 6
#define MB_BTYPE_VLC_BITS 6
#define TEX_VLC_BITS 9

static inline int mpeg1_decode_block_inter(MpegEncContext *s,
                              DCTELEM *block,
                              int n);
static inline int mpeg1_decode_block_intra(MpegEncContext *s,
                              DCTELEM *block,
                              int n);
static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n);
static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
                                        DCTELEM *block,
                                        int n);
static inline int mpeg2_decode_block_intra(MpegEncContext *s,
                                    DCTELEM *block,
                                    int n);
static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s, DCTELEM *block, int n);
static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n);
static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred);
static void exchange_uv(MpegEncContext *s);

extern int XVMC_field_start(MpegEncContext *s, AVCodecContext *avctx);
extern int XVMC_field_end(MpegEncContext *s);
extern void XVMC_pack_pblocks(MpegEncContext *s,int cbp);
extern void XVMC_init_block(MpegEncContext *s);//set s->block

static const enum PixelFormat pixfmt_yuv_420[]= {PIX_FMT_YUV420P,-1};
static const enum PixelFormat pixfmt_yuv_422[]= {PIX_FMT_YUV422P,-1};
static const enum PixelFormat pixfmt_yuv_444[]= {PIX_FMT_YUV444P,-1};
static const enum PixelFormat pixfmt_xvmc_mpg2_420[] = {
                                           PIX_FMT_XVMC_MPEG2_IDCT,
                                           PIX_FMT_XVMC_MPEG2_MC,
                                           -1};

uint8_t ff_mpeg12_static_rl_table_store[2][2][2*MAX_RUN + MAX_LEVEL + 3];

static void init_2d_vlc_rl(RLTable *rl, int use_static)
{
    int i;

    init_vlc(&rl->vlc, TEX_VLC_BITS, rl->n + 2,
             &rl->table_vlc[0][1], 4, 2,
             &rl->table_vlc[0][0], 4, 2, use_static);

    if(use_static)
        rl->rl_vlc[0]= av_mallocz_static(rl->vlc.table_size*sizeof(RL_VLC_ELEM));
    else
        rl->rl_vlc[0]= av_malloc(rl->vlc.table_size*sizeof(RL_VLC_ELEM));

    for(i=0; i<rl->vlc.table_size; i++){
        int code= rl->vlc.table[i][0];
        int len = rl->vlc.table[i][1];
        int level, run;

        if(len==0){ // illegal code
            run= 65;
            level= MAX_LEVEL;
        }else if(len<0){ //more bits needed
            run= 0;
            level= code;
        }else{
            if(code==rl->n){ //esc
                run= 65;
                level= 0;
            }else if(code==rl->n+1){ //eob
                run= 0;
                level= 127;
            }else{
                run=   rl->table_run  [code] + 1;
                level= rl->table_level[code];
            }
        }
        rl->rl_vlc[0][i].len= len;
        rl->rl_vlc[0][i].level= level;
        rl->rl_vlc[0][i].run= run;
    }
}

void ff_mpeg12_common_init(MpegEncContext *s)
{

    s->y_dc_scale_table=
    s->c_dc_scale_table= mpeg2_dc_scale_table[s->intra_dc_precision];

}

void ff_mpeg1_clean_buffers(MpegEncContext *s){
    s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
    s->last_dc[1] = s->last_dc[0];
    s->last_dc[2] = s->last_dc[0];
    memset(s->last_mv, 0, sizeof(s->last_mv));
}


/******************************************/
/* decoding */

static VLC dc_lum_vlc;
static VLC dc_chroma_vlc;
static VLC mv_vlc;
static VLC mbincr_vlc;
static VLC mb_ptype_vlc;
static VLC mb_btype_vlc;
static VLC mb_pat_vlc;
static int done = 0;
void mpeg12_init()
{
	F("%s\n",__FUNCTION__);
	done = 0;
}
static void init_vlcs(void)
{
    

    if (!done) 
    {
        done = 1;

        init_vlc(&dc_lum_vlc, DC_VLC_BITS, 12,
                 ff_mpeg12_vlc_dc_lum_bits, 1, 1,
                 ff_mpeg12_vlc_dc_lum_code, 2, 2, 1);
        init_vlc(&dc_chroma_vlc,  DC_VLC_BITS, 12,
                 ff_mpeg12_vlc_dc_chroma_bits, 1, 1,
                 ff_mpeg12_vlc_dc_chroma_code, 2, 2, 1);
        init_vlc(&mv_vlc, MV_VLC_BITS, 17,
                 &ff_mpeg12_mbMotionVectorTable[0][1], 2, 1,
                 &ff_mpeg12_mbMotionVectorTable[0][0], 2, 1, 1);
        init_vlc(&mbincr_vlc, MBINCR_VLC_BITS, 36,
                 &ff_mpeg12_mbAddrIncrTable[0][1], 2, 1,
                 &ff_mpeg12_mbAddrIncrTable[0][0], 2, 1, 1);
        init_vlc(&mb_pat_vlc, MB_PAT_VLC_BITS, 64,
                 &ff_mpeg12_mbPatTable[0][1], 2, 1,
                 &ff_mpeg12_mbPatTable[0][0], 2, 1, 1);

        init_vlc(&mb_ptype_vlc, MB_PTYPE_VLC_BITS, 7,
                 &table_mb_ptype[0][1], 2, 1,
                 &table_mb_ptype[0][0], 2, 1, 1);
        init_vlc(&mb_btype_vlc, MB_BTYPE_VLC_BITS, 11,
                 &table_mb_btype[0][1], 2, 1,
                 &table_mb_btype[0][0], 2, 1, 1);
        init_rl(&ff_rl_mpeg1, ff_mpeg12_static_rl_table_store[0]);
        init_rl(&ff_rl_mpeg2, ff_mpeg12_static_rl_table_store[1]);

        init_2d_vlc_rl(&ff_rl_mpeg1, 1);
        init_2d_vlc_rl(&ff_rl_mpeg2, 1);
    }
}

static inline int get_dmv(MpegEncContext *s)
{
    if(get_bits1(&s->gb))
        return 1 - (get_bits1(&s->gb) << 1);
    else
        return 0;
}

static inline int get_qscale(MpegEncContext *s)
{
    int qscale = get_bits(&s->gb, 5);
    if (s->q_scale_type) {
        return non_linear_qscale[qscale];
    } else {
        return qscale << 1;
    }
}

/* motion type (for mpeg2) */
#define MT_FIELD 1
#define MT_FRAME 2
#define MT_16X8  2
#define MT_DMV   3

static int mpeg_decode_mb(MpegEncContext *s,
                          DCTELEM block[12][64])
{
    int i, j, k, cbp, val, mb_type, motion_type;
    const int mb_block_count = 4 + (1<< s->chroma_format);

    dprintf(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);

    assert(s->mb_skipped==0);

    if (s->mb_skip_run-- != 0) {
        if (s->pict_type == P_TYPE) {
            s->mb_skipped = 1;
            s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
        } else {
            int mb_type;

            if(s->mb_x)
                mb_type= s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1];
            else
                mb_type= s->current_picture.mb_type[ s->mb_width + (s->mb_y-1)*s->mb_stride - 1]; // FIXME not sure if this is allowed in mpeg at all,
            if(IS_INTRA(mb_type))
                return -1;

            s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]=
                mb_type | MB_TYPE_SKIP;
//            assert(s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1]&(MB_TYPE_16x16|MB_TYPE_16x8));

            if((s->mv[0][0][0]|s->mv[0][0][1]|s->mv[1][0][0]|s->mv[1][0][1])==0)
                s->mb_skipped = 1;
        }

        return 0;
    }

    switch(s->pict_type) {
    default:
    case I_TYPE:
        if (get_bits1(&s->gb) == 0) {
            if (get_bits1(&s->gb) == 0){
                av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in I Frame at %d %d\n", s->mb_x, s->mb_y);
                return -1;
            }
            mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
        } else {
            mb_type = MB_TYPE_INTRA;
        }
        break;
    case P_TYPE:
        mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
        if (mb_type < 0){
            av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
            return -1;
        }
        mb_type = ptype2mb_type[ mb_type ];
        break;
    case B_TYPE:
        mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
        if (mb_type < 0){
            av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
            return -1;
        }
        mb_type = btype2mb_type[ mb_type ];
        break;
    }
    dprintf(s->avctx, "mb_type=%x\n", mb_type);
//    motion_type = 0; /* avoid warning */
    if (IS_INTRA(mb_type)) {
        s->dsp.clear_blocks(s->block[0]);

        if(!s->chroma_y_shift){
            s->dsp.clear_blocks(s->block[6]);
        }

        /* compute dct type */
        if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?
            !s->frame_pred_frame_dct) {
            s->interlaced_dct = get_bits1(&s->gb);
        }

        if (IS_QUANT(mb_type))
            s->qscale = get_qscale(s);

        if (s->concealment_motion_vectors) {
            /* just parse them */
            if (s->picture_structure != PICT_FRAME)
                skip_bits1(&s->gb); /* field select */

            s->mv[0][0][0]= s->last_mv[0][0][0]= s->last_mv[0][1][0] =
                mpeg_decode_motion(s, s->mpeg_f_code[0][0], s->last_mv[0][0][0]);
            s->mv[0][0][1]= s->last_mv[0][0][1]= s->last_mv[0][1][1] =
                mpeg_decode_motion(s, s->mpeg_f_code[0][1], s->last_mv[0][0][1]);

            skip_bits1(&s->gb); /* marker */
        }else
            memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
        s->mb_intra = 1;
#ifdef HAVE_XVMC
        //one 1 we memcpy blocks in xvmcvideo
        if(s->avctx->xvmc_acceleration > 1){
            XVMC_pack_pblocks(s,-1);//inter are always full blocks
            if(s->swap_uv){
                exchange_uv(s);
            }
        }
#endif

        if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
            if(s->flags2 & CODEC_FLAG2_FAST){
                for(i=0;i<6;i++) {
                    mpeg2_fast_decode_block_intra(s, s->pblocks[i], i);
                }
            }else{
                for(i=0;i<mb_block_count;i++) {
                    if (mpeg2_decode_block_intra(s, s->pblocks[i], i) < 0)
                        return -1;
                }
            }
        } else {
            for(i=0;i<6;i++) {
                if (mpeg1_decode_block_intra(s, s->pblocks[i], i) < 0)
                    return -1;
            }
        }
    } else {
        if (mb_type & MB_TYPE_ZERO_MV){
            assert(mb_type & MB_TYPE_CBP);

            s->mv_dir = MV_DIR_FORWARD;
            if(s->picture_structure == PICT_FRAME){
                if(!s->frame_pred_frame_dct)
                    s->interlaced_dct = get_bits1(&s->gb);
                s->mv_type = MV_TYPE_16X16;
            }else{
                s->mv_type = MV_TYPE_FIELD;
                mb_type |= MB_TYPE_INTERLACED;
                s->field_select[0][0]= s->picture_structure - 1;
            }

            if (IS_QUANT(mb_type))
                s->qscale = get_qscale(s);

            s->last_mv[0][0][0] = 0;
            s->last_mv[0][0][1] = 0;
            s->last_mv[0][1][0] = 0;
            s->last_mv[0][1][1] = 0;
            s->mv[0][0][0] = 0;
            s->mv[0][0][1] = 0;
        }else{
            assert(mb_type & MB_TYPE_L0L1);
//FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
            /* get additional motion vector type */
            if (s->frame_pred_frame_dct)
                motion_type = MT_FRAME;
            else{
                motion_type = get_bits(&s->gb, 2);
                if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
                    s->interlaced_dct = get_bits1(&s->gb);
            }

            if (IS_QUANT(mb_type))