svq3.c

Trolltech公司发布的图形界面操作系统。可在qt-embedded-2.3.10平台上编译为嵌入式图形界面操作系统。

/*
 * Copyright (c) 2003 The FFmpeg Project.
 *
 * This library 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 of the License, or (at your option) any later version.
 *
 * This library 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 this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 *
 * How to use this decoder:
 * SVQ3 data is transported within Apple Quicktime files. Quicktime files
 * have stsd atoms to describe media trak properties. A stsd atom for a
 * video trak contains 1 or more ImageDescription atoms. These atoms begin
 * with the 4-byte length of the atom followed by the codec fourcc. Some
 * decoders need information in this atom to operate correctly. Such
 * is the case with SVQ3. In order to get the best use out of this decoder,
 * the calling app must make the SVQ3 ImageDescription atom available
 * via the AVCodecContext's extradata[_size] field:
 *
 * AVCodecContext.extradata = pointer to ImageDescription, first characters 
 * are expected to be 'S', 'V', 'Q', and '3', NOT the 4-byte atom length
 * AVCodecContext.extradata_size = size of ImageDescription atom memory 
 * buffer (which will be the same as the ImageDescription atom size field 
 * from the QT file, minus 4 bytes since the length is missing)
 *
 * You will know you have these parameters passed correctly when the decoder
 * correctly decodes this file:
 *  ftp://ftp.mplayerhq.hu/MPlayer/samples/V-codecs/SVQ3/Vertical400kbit.sorenson3.mov
 *
 */
 
/**
 * @file svq3.c
 * svq3 decoder.
 */

#define FULLPEL_MODE  1 
#define HALFPEL_MODE  2 
#define THIRDPEL_MODE 3
#define PREDICT_MODE  4
 
/* dual scan (from some older h264 draft)
 o-->o-->o   o
         |  /|
 o   o   o / o
 | / |   |/  |
 o   o   o   o
   / 
 o-->o-->o-->o
*/
static const uint8_t svq3_scan[16]={
 0+0*4, 1+0*4, 2+0*4, 2+1*4,
 2+2*4, 3+0*4, 3+1*4, 3+2*4,
 0+1*4, 0+2*4, 1+1*4, 1+2*4,
 0+3*4, 1+3*4, 2+3*4, 3+3*4,
};

static const uint8_t svq3_pred_0[25][2] = {
  { 0, 0 },
  { 1, 0 }, { 0, 1 },
  { 0, 2 }, { 1, 1 }, { 2, 0 },
  { 3, 0 }, { 2, 1 }, { 1, 2 }, { 0, 3 },
  { 0, 4 }, { 1, 3 }, { 2, 2 }, { 3, 1 }, { 4, 0 },
  { 4, 1 }, { 3, 2 }, { 2, 3 }, { 1, 4 },
  { 2, 4 }, { 3, 3 }, { 4, 2 },
  { 4, 3 }, { 3, 4 },
  { 4, 4 }
};

static const int8_t svq3_pred_1[6][6][5] = {
  { { 2,-1,-1,-1,-1 }, { 2, 1,-1,-1,-1 }, { 1, 2,-1,-1,-1 },
    { 2, 1,-1,-1,-1 }, { 1, 2,-1,-1,-1 }, { 1, 2,-1,-1,-1 } },
  { { 0, 2,-1,-1,-1 }, { 0, 2, 1, 4, 3 }, { 0, 1, 2, 4, 3 },
    { 0, 2, 1, 4, 3 }, { 2, 0, 1, 3, 4 }, { 0, 4, 2, 1, 3 } },
  { { 2, 0,-1,-1,-1 }, { 2, 1, 0, 4, 3 }, { 1, 2, 4, 0, 3 },
    { 2, 1, 0, 4, 3 }, { 2, 1, 4, 3, 0 }, { 1, 2, 4, 0, 3 } },
  { { 2, 0,-1,-1,-1 }, { 2, 0, 1, 4, 3 }, { 1, 2, 0, 4, 3 },
    { 2, 1, 0, 4, 3 }, { 2, 1, 3, 4, 0 }, { 2, 4, 1, 0, 3 } },
  { { 0, 2,-1,-1,-1 }, { 0, 2, 1, 3, 4 }, { 1, 2, 3, 0, 4 },
    { 2, 0, 1, 3, 4 }, { 2, 1, 3, 0, 4 }, { 2, 0, 4, 3, 1 } },
  { { 0, 2,-1,-1,-1 }, { 0, 2, 4, 1, 3 }, { 1, 4, 2, 0, 3 },
    { 4, 2, 0, 1, 3 }, { 2, 0, 1, 4, 3 }, { 4, 2, 1, 0, 3 } },
};

static const struct { uint8_t run; uint8_t level; } svq3_dct_tables[2][16] = {
  { { 0, 0 }, { 0, 1 }, { 1, 1 }, { 2, 1 }, { 0, 2 }, { 3, 1 }, { 4, 1 }, { 5, 1 },
    { 0, 3 }, { 1, 2 }, { 2, 2 }, { 6, 1 }, { 7, 1 }, { 8, 1 }, { 9, 1 }, { 0, 4 } },
  { { 0, 0 }, { 0, 1 }, { 1, 1 }, { 0, 2 }, { 2, 1 }, { 0, 3 }, { 0, 4 }, { 0, 5 },
    { 3, 1 }, { 4, 1 }, { 1, 2 }, { 1, 3 }, { 0, 6 }, { 0, 7 }, { 0, 8 }, { 0, 9 } }
};

static const uint32_t svq3_dequant_coeff[32] = {
   3881,  4351,  4890,  5481,  6154,  6914,  7761,  8718,
   9781, 10987, 12339, 13828, 15523, 17435, 19561, 21873,
  24552, 27656, 30847, 34870, 38807, 43747, 49103, 54683,
  61694, 68745, 77615, 89113,100253,109366,126635,141533
};


static void svq3_luma_dc_dequant_idct_c(DCTELEM *block, int qp){
    const int qmul= svq3_dequant_coeff[qp];
#define stride 16
    int i;
    int temp[16];
    static const int x_offset[4]={0, 1*stride, 4* stride,  5*stride};
    static const int y_offset[4]={0, 2*stride, 8* stride, 10*stride};

    for(i=0; i<4; i++){
        const int offset= y_offset[i];
        const int z0= 13*(block[offset+stride*0] +    block[offset+stride*4]);
        const int z1= 13*(block[offset+stride*0] -    block[offset+stride*4]);
        const int z2=  7* block[offset+stride*1] - 17*block[offset+stride*5];
        const int z3= 17* block[offset+stride*1] +  7*block[offset+stride*5];

        temp[4*i+0]= z0+z3;
        temp[4*i+1]= z1+z2;
        temp[4*i+2]= z1-z2;
        temp[4*i+3]= z0-z3;
    }

    for(i=0; i<4; i++){
        const int offset= x_offset[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[stride*0 +offset]= ((z0 + z3)*qmul + 0x80000)>>20;
        block[stride*2 +offset]= ((z1 + z2)*qmul + 0x80000)>>20;
        block[stride*8 +offset]= ((z1 - z2)*qmul + 0x80000)>>20;
        block[stride*10+offset]= ((z0 - z3)*qmul + 0x80000)>>20;
    }
}
#undef stride

static void svq3_add_idct_c (uint8_t *dst, DCTELEM *block, int stride, int qp, int dc){
    const int qmul= svq3_dequant_coeff[qp];
    int i;
    uint8_t *cm = cropTbl + MAX_NEG_CROP;

    if (dc) {
        dc = 13*13*((dc == 1) ? 1538*block[0] : ((qmul*(block[0] >> 3)) / 2));
        block[0] = 0;
    }

    for (i=0; i < 4; i++) {
        const int z0= 13*(block[0 + 4*i] +    block[2 + 4*i]);
        const int z1= 13*(block[0 + 4*i] -    block[2 + 4*i]);
        const int z2=  7* block[1 + 4*i] - 17*block[3 + 4*i];
        const int z3= 17* block[1 + 4*i] +  7*block[3 + 4*i];

        block[0 + 4*i]= z0 + z3;
        block[1 + 4*i]= z1 + z2;
        block[2 + 4*i]= z1 - z2;
        block[3 + 4*i]= z0 - z3;
    }

    for (i=0; i < 4; i++) {
        const int z0= 13*(block[i + 4*0] +    block[i + 4*2]);
        const int z1= 13*(block[i + 4*0] -    block[i + 4*2]);
        const int z2=  7* block[i + 4*1] - 17*block[i + 4*3];
        const int z3= 17* block[i + 4*1] +  7*block[i + 4*3];
        const int rr= (dc + 0x80000);

        dst[i + stride*0]= cm[ dst[i + stride*0] + (((z0 + z3)*qmul + rr) >> 20) ];
        dst[i + stride*1]= cm[ dst[i + stride*1] + (((z1 + z2)*qmul + rr) >> 20) ];
        dst[i + stride*2]= cm[ dst[i + stride*2] + (((z1 - z2)*qmul + rr) >> 20) ];
        dst[i + stride*3]= cm[ dst[i + stride*3] + (((z0 - z3)*qmul + rr) >> 20) ];
    }
}

static void pred4x4_down_left_svq3_c(uint8_t *src, uint8_t *topright, int stride){
    LOAD_TOP_EDGE    
    LOAD_LEFT_EDGE    
    const __attribute__((unused)) int unu0= t0;
    const __attribute__((unused)) int unu1= l0;

    src[0+0*stride]=(l1 + t1)>>1;
    src[1+0*stride]=
    src[0+1*stride]=(l2 + t2)>>1;
    src[2+0*stride]=
    src[1+1*stride]=
    src[0+2*stride]=
    src[3+0*stride]=
    src[2+1*stride]=
    src[1+2*stride]=
    src[0+3*stride]=
    src[3+1*stride]=
    src[2+2*stride]=
    src[1+3*stride]=
    src[3+2*stride]=
    src[2+3*stride]=
    src[3+3*stride]=(l3 + t3)>>1;
}

static void pred16x16_plane_svq3_c(uint8_t *src, int stride){
    pred16x16_plane_compat_c(src, stride, 1);
}

static inline int svq3_decode_block (GetBitContext *gb, DCTELEM *block,
				     int index, const int type) {

  static const uint8_t *const scan_patterns[4] =
  { luma_dc_zigzag_scan, zigzag_scan, svq3_scan, chroma_dc_scan };

  int run, level, sign, vlc, limit;
  const int intra = (3 * type) >> 2;
  const uint8_t *const scan = scan_patterns[type];

  for (limit=(16 >> intra); index < 16; index=limit, limit+=8) {
    for (; (vlc = svq3_get_ue_golomb (gb)) != 0; index++) {

      if (vlc == INVALID_VLC)
	return -1;

      sign = (vlc & 0x1) - 1;
      vlc  = (vlc + 1) >> 1;

      if (type == 3) {
	if (vlc < 3) {
	  run   = 0;
	  level = vlc;
	} else if (vlc < 4) {
	  run   = 1;
	  level = 1;
	} else {
	  run   = (vlc & 0x3);
	  level = ((vlc + 9) >> 2) - run;
	}
      } else {
	if (vlc < 16) {
	  run   = svq3_dct_tables[intra][vlc].run;
	  level = svq3_dct_tables[intra][vlc].level;
	} else if (intra) {
	  run   = (vlc & 0x7);
	  level = (vlc >> 3) + ((run == 0) ? 8 : ((run < 2) ? 2 : ((run < 5) ? 0 : -1)));
	} else {
	  run   = (vlc & 0xF);
	  level = (vlc >> 4) + ((run == 0) ? 4 : ((run < 3) ? 2 : ((run < 10) ? 1 : 0)));
	}
      }

      if ((index += run) >= limit)
	return -1;

      block[scan[index]] = (level ^ sign) - sign;
    }

    if (type != 2) {
      break;
    }
  }

  return 0;
}

static inline void svq3_mc_dir_part (MpegEncContext *s,
				     int x, int y, int width, int height,
				     int mx, int my, int dxy,
				     int thirdpel, int dir, int avg) {

  const Picture *pic = (dir == 0) ? &s->last_picture : &s->next_picture;
  uint8_t *src, *dest;
  int i, emu = 0;
  int blocksize= 2 - (width>>3); //16->0, 8->1, 4->2

  mx += x;
  my += y;
  
  if (mx < 0 || mx >= (s->h_edge_pos - width  - 1) ||
      my < 0 || my >= (s->v_edge_pos - height - 1)) {

    if ((s->flags & CODEC_FLAG_EMU_EDGE)) {
      emu = 1;
    }

    mx = clip (mx, -16, (s->h_edge_pos - width  + 15));
    my = clip (my, -16, (s->v_edge_pos - height + 15));
  }

  /* form component predictions */
  dest = s->current_picture.data[0] + x + y*s->linesize;
  src  = pic->data[0] + mx + my*s->linesize;

  if (emu) {
    ff_emulated_edge_mc (s->edge_emu_buffer, src, s->linesize, (width + 1), (height + 1),
			 mx, my, s->h_edge_pos, s->v_edge_pos);
    src = s->edge_emu_buffer;
  }
  if(thirdpel)
    (avg ? s->dsp.avg_tpel_pixels_tab : s->dsp.put_tpel_pixels_tab)[dxy](dest, src, s->linesize, width, height);
  else
    (avg ? s->dsp.avg_pixels_tab : s->dsp.put_pixels_tab)[blocksize][dxy](dest, src, s->linesize, height);

  if (!(s->flags & CODEC_FLAG_GRAY)) {
    mx	   = (mx + (mx < (int) x)) >> 1;
    my	   = (my + (my < (int) y)) >> 1;
    width  = (width  >> 1);
    height = (height >> 1);
    blocksize++;

    for (i=1; i < 3; i++) {
      dest = s->current_picture.data[i] + (x >> 1) + (y >> 1)*s->uvlinesize;
      src  = pic->data[i] + mx + my*s->uvlinesize;

      if (emu) {
        ff_emulated_edge_mc (s->edge_emu_buffer, src, s->uvlinesize, (width + 1), (height + 1),
			     mx, my, (s->h_edge_pos >> 1), (s->v_edge_pos >> 1));
        src = s->edge_emu_buffer;
      }
      if(thirdpel)
        (avg ? s->dsp.avg_tpel_pixels_tab : s->dsp.put_tpel_pixels_tab)[dxy](dest, src, s->uvlinesize, width, height);
      else
        (avg ? s->dsp.avg_pixels_tab : s->dsp.put_pixels_tab)[blocksize][dxy](dest, src, s->uvlinesize, height);
    }
  }
}

static inline int svq3_mc_dir (H264Context *h, int size, int mode, int dir, int avg) {

  int i, j, k, mx, my, dx, dy, x, y;
  MpegEncContext *const s = (MpegEncContext *) h;
  const int part_width  = ((size & 5) == 4) ? 4 : 16 >> (size & 1);
  const int part_height = 16 >> ((unsigned) (size + 1) / 3);
  const int extra_width = (mode == PREDICT_MODE) ? -16*6 : 0;
  const int h_edge_pos  = 6*(s->h_edge_pos - part_width ) - extra_width;
  const int v_edge_pos  = 6*(s->v_edge_pos - part_height) - extra_width;

  for (i=0; i < 16; i+=part_height) {
    for (j=0; j < 16; j+=part_width) {
      const int b_xy = (4*s->mb_x+(j>>2)) + (4*s->mb_y+(i>>2))*h->b_stride;
      int dxy;
      x = 16*s->mb_x + j;
      y = 16*s->mb_y + i;
      k = ((j>>2)&1) + ((i>>1)&2) + ((j>>1)&4) + (i&8);

      if (mode != PREDICT_MODE) {
	pred_motion (h, k, (part_width >> 2), dir, 1, &mx, &my);
      } else {
	mx = s->next_picture.motion_val[0][b_xy][0]<<1;
	my = s->next_picture.motion_val[0][b_xy][1]<<1;

	if (dir == 0) {
	  mx = ((mx * h->frame_num_offset) / h->prev_frame_num_offset + 1)>>1;
	  my = ((my * h->frame_num_offset) / h->prev_frame_num_offset + 1)>>1;
	} else {
	  mx = ((mx * (h->frame_num_offset - h->prev_frame_num_offset)) / h->prev_frame_num_offset + 1)>>1;
	  my = ((my * (h->frame_num_offset - h->prev_frame_num_offset)) / h->prev_frame_num_offset + 1)>>1;
	}
      }

      /* clip motion vector prediction to frame border */
      mx = clip (mx, extra_width - 6*x, h_edge_pos - 6*x);
      my = clip (my, extra_width - 6*y, v_edge_pos - 6*y);

      /* get (optional) motion vector differential */
      if (mode == PREDICT_MODE) {
	dx = dy = 0;
      } else {
	dy = svq3_get_se_golomb (&s->gb);
	dx = svq3_get_se_golomb (&s->gb);

	if (dx == INVALID_VLC || dy == INVALID_VLC) {
	  return -1;
	}
      }

      /* compute motion vector */
      if (mode == THIRDPEL_MODE) {
	int fx, fy;
	mx = ((mx + 1)>>1) + dx;
	my = ((my + 1)>>1) + dy;
	fx= ((unsigned)(mx + 0x3000))/3 - 0x1000;
	fy= ((unsigned)(my + 0x3000))/3 - 0x1000;
	dxy= (mx - 3*fx) + 4*(my - 3*fy);

	svq3_mc_dir_part (s, x, y, part_width, part_height, fx, fy, dxy, 1, dir, avg);
	mx += mx;
	my += my;
      } else if (mode == HALFPEL_MODE || mode == PREDICT_MODE) {
	mx = ((unsigned)(mx + 1 + 0x3000))/3 + dx - 0x1000;
	my = ((unsigned)(my + 1 + 0x3000))/3 + dy - 0x1000;
	dxy= (mx&1) + 2*(my&1);

	svq3_mc_dir_part (s, x, y, part_width, part_height, mx>>1, my>>1, dxy, 0, dir, avg);
	mx *= 3;
	my *= 3;
      } else {
	mx = ((unsigned)(mx + 3 + 0x6000))/6 + dx - 0x1000;
	my = ((unsigned)(my + 3 + 0x6000))/6 + dy - 0x1000;

	svq3_mc_dir_part (s, x, y, part_width, part_height, mx, my, 0, 0, dir, avg);
	mx *= 6;
	my *= 6;
      }

      /* update mv_cache */
      if (mode != PREDICT_MODE) {
	int32_t mv = pack16to32(mx,my);

	if (part_height == 8 && i < 8) {
	  *(int32_t *) h->mv_cache[dir][scan8[k] + 1*8] = mv;

	  if (part_width == 8 && j < 8) {
	    *(int32_t *) h->mv_cache[dir][scan8[k] + 1 + 1*8] = mv;
	  }
	}
	if (part_width == 8 && j < 8) {
	  *(int32_t *) h->mv_cache[dir][scan8[k] + 1] = mv;
	}
	if (part_width == 4 || part_height == 4) {
	  *(int32_t *) h->mv_cache[dir][scan8[k]] = mv;
	}
      }

      /* write back motion vectors */
      fill_rectangle(s->current_picture.motion_val[dir][b_xy], part_width>>2, part_height>>2, h->b_stride, pack16to32(mx,my), 4);
    }
  }

  return 0;
}

static int svq3_decode_mb (H264Context *h, unsigned int mb_type) {
  int i, j, k, m, dir, mode;
  int cbp = 0;
  uint32_t vlc;
  int8_t *top, *left;
  MpegEncContext *const s = (MpegEncContext *) h;
  const int mb_xy = s->mb_x + s->mb_y*s->mb_stride;
  const int b_xy = 4*s->mb_x + 4*s->mb_y*h->b_stride;

  h->top_samples_available	= (s->mb_y == 0) ? 0x33FF : 0xFFFF;
  h->left_samples_available	= (s->mb_x == 0) ? 0x5F5F : 0xFFFF;
  h->topright_samples_available	= 0xFFFF;

  if (mb_type == 0) {		/* SKIP */
    if (s->pict_type == P_TYPE || s->next_picture.mb_type[mb_xy] == -1) {
      svq3_mc_dir_part (s, 16*s->mb_x, 16*s->mb_y, 16, 16, 0, 0, 0, 0, 0, 0);

      if (s->pict_type == B_TYPE) {
	svq3_mc_dir_part (s, 16*s->mb_x, 16*s->mb_y, 16, 16, 0, 0, 0, 0, 1, 1);
      }

      mb_type = MB_TYPE_SKIP;
    } else {
      svq3_mc_dir (h, s->next_picture.mb_type[mb_xy], PREDICT_MODE, 0, 0);
      svq3_mc_dir (h, s->next_picture.mb_type[mb_xy], PREDICT_MODE, 1, 1);

      mb_type = MB_TYPE_16x16;
    }
  } else if (mb_type < 8) {	/* INTER */
    if (h->thirdpel_flag && h->halfpel_flag == !get_bits (&s->gb, 1)) {
      mode = THIRDPEL_MODE;
    } else if (h->halfpel_flag && h->thirdpel_flag == !get_bits (&s->gb, 1)) {
      mode = HALFPEL_MODE;
    } else {
      mode = FULLPEL_MODE;
    }

    /* fill caches */
    /* note ref_cache should contain here:
        ????????
        ???11111
        N??11111
        N??11111
        N??11111
        N
    */
    
    for (m=0; m < 2; m++) {
      if (s->mb_x > 0 && h->intra4x4_pred_mode[mb_xy - 1][0] != -1) {
	for (i=0; i < 4; i++) {
	  *(uint32_t *) h->mv_cache[m][scan8[0] - 1 + i*8] = *(uint32_t *) s->current_picture.motion_val[m][b_xy - 1 + i*h->b_stride];
	}
      } else {