/* * MPEG1 encoder / MPEG2 decoder * Copyright (c) 2000,2001 Fabrice Bellard. * * 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 */ //#define DEBUG #include "avcodec.h" #include "dsputil.h" #include "mpegvideo.h" #include "mpeg12data.h" #if 1 #define PRINT_QP(a, b) {} #else #define PRINT_QP(a, b) printf(a, b) #endif /* Start codes. */ #define SEQ_END_CODE 0x000001b7 #define SEQ_START_CODE 0x000001b3 #define GOP_START_CODE 0x000001b8 #define PICTURE_START_CODE 0x00000100 #define SLICE_MIN_START_CODE 0x00000101 #define SLICE_MAX_START_CODE 0x000001af #define EXT_START_CODE 0x000001b5 #define USER_START_CODE 0x000001b2 #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 void mpeg1_encode_block(MpegEncContext *s, DCTELEM *block, int component); static void mpeg1_encode_motion(MpegEncContext *s, int val); static void mpeg1_skip_picture(MpegEncContext *s, int pict_num); 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 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 int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred); static UINT16 mv_penalty[MAX_FCODE+1][MAX_MV*2+1]; static UINT8 fcode_tab[MAX_MV*2+1]; static inline int get_bits_diff(MpegEncContext *s){ int bits,ret; bits= get_bit_count(&s->pb); ret= bits - s->last_bits; s->last_bits=bits; return ret; } static void init_2d_vlc_rl(RLTable *rl) { 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); 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; } } static void put_header(MpegEncContext *s, int header) { align_put_bits(&s->pb); put_bits(&s->pb, 16, header>>16); put_bits(&s->pb, 16, header&0xFFFF); } /* put sequence header if needed */ static void mpeg1_encode_sequence_header(MpegEncContext *s) { unsigned int vbv_buffer_size; unsigned int fps, v; int n; UINT64 time_code; if (s->current_picture.key_frame) { /* mpeg1 header repeated every gop */ put_header(s, SEQ_START_CODE); /* search closest frame rate */ { int i, dmin, d; s->frame_rate_index = 0; dmin = 0x7fffffff; for(i=1;i<9;i++) { d = abs(s->frame_rate - frame_rate_tab[i]); if (d < dmin) { dmin = d; s->frame_rate_index = i; } } } put_bits(&s->pb, 12, s->width); put_bits(&s->pb, 12, s->height); put_bits(&s->pb, 4, 1); /* 1/1 aspect ratio */ put_bits(&s->pb, 4, s->frame_rate_index); v = s->bit_rate / 400; if (v > 0x3ffff) v = 0x3ffff; put_bits(&s->pb, 18, v); put_bits(&s->pb, 1, 1); /* marker */ if(s->avctx->rc_buffer_size) vbv_buffer_size = s->avctx->rc_buffer_size; else /* VBV calculation: Scaled so that a VCD has the proper VBV size of 40 kilobytes */ vbv_buffer_size = (( 20 * s->bit_rate) / (1151929 / 2)) * 8 * 1024; put_bits(&s->pb, 10, (vbv_buffer_size + 16383) / 16384); put_bits(&s->pb, 1, 1); /* constrained parameter flag */ put_bits(&s->pb, 1, 0); /* no custom intra matrix */ put_bits(&s->pb, 1, 0); /* no custom non intra matrix */ put_header(s, GOP_START_CODE); put_bits(&s->pb, 1, 0); /* do drop frame */ /* time code : we must convert from the real frame rate to a fake mpeg frame rate in case of low frame rate */ fps = frame_rate_tab[s->frame_rate_index]; time_code = (INT64)s->fake_picture_number * FRAME_RATE_BASE; s->gop_picture_number = s->fake_picture_number; put_bits(&s->pb, 5, (UINT32)((time_code / (fps * 3600)) % 24)); put_bits(&s->pb, 6, (UINT32)((time_code / (fps * 60)) % 60)); put_bits(&s->pb, 1, 1); put_bits(&s->pb, 6, (UINT32)((time_code / fps) % 60)); put_bits(&s->pb, 6, (UINT32)((time_code % fps) / FRAME_RATE_BASE)); put_bits(&s->pb, 1, 1); /* closed gop */ put_bits(&s->pb, 1, 0); /* broken link */ } if (s->frame_rate < (24 * FRAME_RATE_BASE) && s->picture_number > 0) { /* insert empty P pictures to slow down to the desired frame rate. Each fake pictures takes about 20 bytes */ fps = frame_rate_tab[s->frame_rate_index]; n = (((INT64)s->picture_number * fps) / s->frame_rate) - 1; while (s->fake_picture_number < n) { mpeg1_skip_picture(s, s->fake_picture_number - s->gop_picture_number); s->fake_picture_number++; } } } /* insert a fake P picture */ static void mpeg1_skip_picture(MpegEncContext *s, int pict_num) { unsigned int mb_incr; /* mpeg1 picture header */ put_header(s, PICTURE_START_CODE); /* temporal reference */ put_bits(&s->pb, 10, pict_num & 0x3ff); put_bits(&s->pb, 3, P_TYPE); put_bits(&s->pb, 16, 0xffff); /* non constant bit rate */ put_bits(&s->pb, 1, 1); /* integer coordinates */ put_bits(&s->pb, 3, 1); /* forward_f_code */ put_bits(&s->pb, 1, 0); /* extra bit picture */ /* only one slice */ put_header(s, SLICE_MIN_START_CODE); put_bits(&s->pb, 5, 1); /* quantizer scale */ put_bits(&s->pb, 1, 0); /* slice extra information */ mb_incr = 1; put_bits(&s->pb, mbAddrIncrTable[mb_incr - 1][1], mbAddrIncrTable[mb_incr - 1][0]); /* empty macroblock */ put_bits(&s->pb, 3, 1); /* motion only */ /* zero motion x & y */ put_bits(&s->pb, 1, 1); put_bits(&s->pb, 1, 1); /* output a number of empty slice */ mb_incr = s->mb_width * s->mb_height - 1; while (mb_incr > 33) { put_bits(&s->pb, 11, 0x008); mb_incr -= 33; } put_bits(&s->pb, mbAddrIncrTable[mb_incr - 1][1], mbAddrIncrTable[mb_incr - 1][0]); /* empty macroblock */ put_bits(&s->pb, 3, 1); /* motion only */ /* zero motion x & y */ put_bits(&s->pb, 1, 1); put_bits(&s->pb, 1, 1); } static void common_init(MpegEncContext *s) { s->y_dc_scale_table= s->c_dc_scale_table= ff_mpeg1_dc_scale_table; } void mpeg1_encode_picture_header(MpegEncContext *s, int picture_number) { mpeg1_encode_sequence_header(s); /* mpeg1 picture header */ put_header(s, PICTURE_START_CODE); /* temporal reference */ put_bits(&s->pb, 10, (s->fake_picture_number - s->gop_picture_number) & 0x3ff); s->fake_picture_number++; put_bits(&s->pb, 3, s->pict_type); put_bits(&s->pb, 16, 0xffff); /* non constant bit rate */ if (s->pict_type == P_TYPE) { put_bits(&s->pb, 1, 0); /* half pel coordinates */ put_bits(&s->pb, 3, s->f_code); /* forward_f_code */ } put_bits(&s->pb, 1, 0); /* extra bit picture */ /* only one slice */ put_header(s, SLICE_MIN_START_CODE); put_bits(&s->pb, 5, s->qscale); /* quantizer scale */ put_bits(&s->pb, 1, 0); /* slice extra information */ } void mpeg1_encode_mb(MpegEncContext *s, DCTELEM block[6][64], int motion_x, int motion_y) { int mb_incr, i, cbp, mb_x, mb_y; mb_x = s->mb_x; mb_y = s->mb_y; /* compute cbp */ cbp = 0; for(i=0;i<6;i++) { if (s->block_last_index[i] >= 0) cbp |= 1 << (5 - i); } /* skip macroblock, except if first or last macroblock of a slice */ if ((cbp | motion_x | motion_y) == 0 && (!((mb_x | mb_y) == 0 || (mb_x == s->mb_width - 1 && mb_y == s->mb_height - 1)))) { s->mb_incr++; s->qscale -= s->dquant; s->skip_count++; s->misc_bits++; s->last_bits++; } else { /* output mb incr */ mb_incr = s->mb_incr; while (mb_incr > 33) { put_bits(&s->pb, 11, 0x008); mb_incr -= 33; } put_bits(&s->pb, mbAddrIncrTable[mb_incr - 1][1], mbAddrIncrTable[mb_incr - 1][0]); if (s->pict_type == I_TYPE) { if(s->dquant && cbp){ put_bits(&s->pb, 2, 1); /* macroblock_type : macroblock_quant = 1 */ put_bits(&s->pb, 5, s->qscale); }else{ put_bits(&s->pb, 1, 1); /* macroblock_type : macroblock_quant = 0 */ s->qscale -= s->dquant; } s->misc_bits+= get_bits_diff(s); s->i_count++; } else { if (s->mb_intra) { if(s->dquant && cbp){ put_bits(&s->pb, 6, 0x01); put_bits(&s->pb, 5, s->qscale); }else{ put_bits(&s->pb, 5, 0x03); s->qscale -= s->dquant; } s->misc_bits+= get_bits_diff(s); s->i_count++; } else { if (cbp != 0) { if (motion_x == 0 && motion_y == 0) { if(s->dquant){ put_bits(&s->pb, 5, 1); /* macroblock_pattern & quant */ put_bits(&s->pb, 5, s->qscale); }else{ put_bits(&s->pb, 2, 1); /* macroblock_pattern only */ } s->misc_bits+= get_bits_diff(s); put_bits(&s->pb, mbPatTable[cbp - 1][1], mbPatTable[cbp - 1][0]); } else { if(s->dquant){ put_bits(&s->pb, 5, 2); /* motion + cbp */ put_bits(&s->pb, 5, s->qscale); }else{ put_bits(&s->pb, 1, 1); /* motion + cbp */ } s->misc_bits+= get_bits_diff(s); mpeg1_encode_motion(s, motion_x - s->last_mv[0][0][0]); mpeg1_encode_motion(s, motion_y - s->last_mv[0][0][1]); s->mv_bits+= get_bits_diff(s); put_bits(&s->pb, mbPatTable[cbp - 1][1], mbPatTable[cbp - 1][0]); } } else { put_bits(&s->pb, 3, 1); /* motion only */ mpeg1_encode_motion(s, motion_x - s->last_mv[0][0][0]); mpeg1_encode_motion(s, motion_y - s->last_mv[0][0][1]); s->qscale -= s->dquant; s->mv_bits+= get_bits_diff(s); } s->f_count++; } } for(i=0;i<6;i++) { if (cbp & (1 << (5 - i))) { mpeg1_encode_block(s, block[i], i); } } s->mb_incr = 1; if(s->mb_intra) s->i_tex_bits+= get_bits_diff(s); else s->p_tex_bits+= get_bits_diff(s); } s->last_mv[0][0][0] = motion_x; s->last_mv[0][0][1] = motion_y; } static void mpeg1_encode_motion(MpegEncContext *s, int val) { int code, bit_size, l, m, bits, range, sign; if (val == 0) { /* zero vector */ code = 0; put_bits(&s->pb, mbMotionVectorTable[0][1], mbMotionVectorTable[0][0]); } else { bit_size = s->f_code - 1; range = 1 << bit_size; /* modulo encoding */ l = 16 * range; m = 2 * l; if (val < -l) { val += m; } else if (val >= l) { val -= m; } if (val >= 0) { val--; code = (val >> bit_size) + 1; bits = val & (range - 1); sign = 0; } else { val = -val; val--; code = (val >> bit_size) + 1; bits = val & (range - 1); sign = 1; } put_bits(&s->pb, mbMotionVectorTable[code][1], mbMotionVectorTable[code][0]); put_bits(&s->pb, 1, sign); if (bit_size > 0) { put_bits(&s->pb, bit_size, bits); } } } void ff_mpeg1_encode_init(MpegEncContext *s) { static int done=0; common_init(s); if(!done){ int f_code; int mv; int i; done=1; init_rl(&rl_mpeg1); for(i=0; i<64; i++) { mpeg1_max_level[0][i]= rl_mpeg1.max_level[0][i]; mpeg1_index_run[0][i]= rl_mpeg1.index_run[0][i]; } /* build unified dc encoding tables */ for(i=-255; i<256; i++) { int adiff, index; int bits, code; int diff=i; adiff = ABS(diff); if(diff<0) diff--; index = vlc_dc_table[adiff]; bits= vlc_dc_lum_bits[index] + index; code= (vlc_dc_lum_code[index]<<index) + (diff & ((1 << index) - 1)); mpeg1_lum_dc_uni[i+255]= bits + (code<<8); bits= vlc_dc_chroma_bits[index] + index; code= (vlc_dc_chroma_code[index]<<index) + (diff & ((1 << index) - 1)); mpeg1_chr_dc_uni[i+255]= bits + (code<<8); } for(f_code=1; f_code<=MAX_FCODE; f_code++){ for(mv=-MAX_MV; mv<=MAX_MV; mv++){ int len; if(mv==0) len= mbMotionVectorTable[0][1]; else{ int val, bit_size, range, code; bit_size = s->f_code - 1; range = 1 << bit_size; val=mv; if (val < 0) val = -val; val--; code = (val >> bit_size) + 1; if(code<17){ len= mbMotionVectorTable[code][1] + 1 + bit_size; }else{ len= mbMotionVectorTable[16][1] + 2 + bit_size; } } mv_penalty[f_code][mv+MAX_MV]= len; } } for(f_code=MAX_FCODE; f_code>0; f_code--){ for(mv=-(8<<f_code); mv<(8<<f_code); mv++){ fcode_tab[mv+MAX_MV]= f_code; } } } s->mv_penalty= mv_penalty; s->fcode_tab= fcode_tab; s->min_qcoeff=-255; s->max_qcoeff= 255; s->intra_quant_bias= 3<<(QUANT_BIAS_SHIFT-3); //(a + x*3/8)/x s->inter_quant_bias= 0; } static inline void encode_dc(MpegEncContext *s, int diff, int component) { if (component == 0) { put_bits( &s->pb, mpeg1_lum_dc_uni[diff+255]&0xFF, mpeg1_lum_dc_uni[diff+255]>>8); } else { put_bits( &s->pb, mpeg1_chr_dc_uni[diff+255]&0xFF, mpeg1_chr_dc_uni[diff+255]>>8); } } static void mpeg1_encode_block(MpegEncContext *s, DCTELEM *block, int n) { int alevel, level, last_non_zero, dc, diff, i, j, run, last_index, sign; int code, component; // RLTable *rl = &rl_mpeg1; last_index = s->block_last_index[n]; /* DC coef */ if (s->mb_intra) { component = (n <= 3 ? 0 : n - 4 + 1); dc = block[0]; /* overflow is impossible */ diff = dc - s->last_dc[component]; encode_dc(s, diff, component); s->last_dc[component] = dc; i = 1; } else { /* encode the first coefficient : needs to be done here because it is handled slightly differently */ level = block[0]; if (abs(level) == 1) { code = ((UINT32)level >> 31); /* the sign bit */ put_bits(&s->pb, 2, code | 0x02); i = 1; } else { i = 0; last_non_zero = -1; goto next_coef; } } /* now quantify & encode AC coefs */ last_non_zero = i - 1; for(;i<=last_index;i++) { j = s->intra_scantable.permutated[i]; level = block[j]; next_coef: #if 0 if (level != 0) dprintf("level[%d]=%d\n", i, level); #endif /* encode using VLC */ if (level != 0) { run = i - last_non_zero - 1; alevel= level; MASK_ABS(sign, alevel) sign&=1; // code = get_rl_index(rl, 0, run, alevel); if (alevel > mpeg1_max_level[0][run]) code= 111; /*rl->n*/ else code= mpeg1_index_run[0][run] + alevel - 1; if (code < 111 /* rl->n */) { /* store the vlc & sign at once */ put_bits(&s->pb, mpeg1_vlc[code][1]+1, (mpeg1_vlc[code][0]<<1) + sign); } else { /* escape seems to be pretty rare <5% so i dont optimize it */ put_bits(&s->pb, mpeg1_vlc[111/*rl->n*/][1], mpeg1_vlc[111/*rl->n*/][0]); /* escape: only clip in this case */ put_bits(&s->pb, 6, run); if (alevel < 128) { put_bits(&s->pb, 8, level & 0xff); } else { if (level < 0) { put_bits(&s->pb, 16, 0x8001 + level + 255); } else { put_bits(&s->pb, 16, level & 0xffff); } } } last_non_zero = i; } } /* end of block */ put_bits(&s->pb, 2, 0x2); } /******************************************/ /* 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 void init_vlcs(MpegEncContext *s) { static int done = 0; if (!done) { done = 1; init_vlc(&dc_lum_vlc, DC_VLC_BITS, 12, vlc_dc_lum_bits, 1, 1, vlc_dc_lum_code, 2, 2); init_vlc(&dc_chroma_vlc, DC_VLC_BITS, 12, vlc_dc_chroma_bits, 1, 1, vlc_dc_chroma_code, 2, 2); init_vlc(&mv_vlc, MV_VLC_BITS, 17, &mbMotionVectorTable[0][1], 2, 1, &mbMotionVectorTable[0][0], 2, 1); init_vlc(&mbincr_vlc, MBINCR_VLC_BITS, 35, &mbAddrIncrTable[0][1], 2, 1, &mbAddrIncrTable[0][0], 2, 1); init_vlc(&mb_pat_vlc, MB_PAT_VLC_BITS, 63, &mbPatTable[0][1], 2, 1, &mbPatTable[0][0], 2, 1); init_vlc(&mb_ptype_vlc, MB_PTYPE_VLC_BITS, 32, &table_mb_ptype[0][1], 2, 1, &table_mb_ptype[0][0], 2, 1); init_vlc(&mb_btype_vlc, MB_BTYPE_VLC_BITS, 32, &table_mb_btype[0][1], 2, 1, &table_mb_btype[0][0], 2, 1); init_rl(&rl_mpeg1); init_rl(&rl_mpeg2); init_2d_vlc_rl(&rl_mpeg1); init_2d_vlc_rl(&rl_mpeg2); } } 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; if (s->mpeg2) { if (s->q_scale_type) { qscale = non_linear_qscale[get_bits(&s->gb, 5)]; } else { qscale = get_bits(&s->gb, 5) << 1; } } else { /* for mpeg1, we use the generic unquant code */ qscale = get_bits(&s->gb, 5); } return qscale; } /* 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[6][64]) { int i, j, k, cbp, val, mb_type, motion_type; dprintf("decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y); if (--s->mb_incr != 0) { /* skip mb */ s->mb_intra = 0; for(i=0;i<6;i++) s->block_last_index[i] = -1; s->mv_type = MV_TYPE_16X16; if (s->pict_type == P_TYPE) { /* if P type, zero motion vector is implied */ s->mv_dir = MV_DIR_FORWARD; s->mv[0][0][0] = s->mv[0][0][1] = 0; s->last_mv[0][0][0] = s->last_mv[0][0][1] = 0; s->last_mv[0][1][0] = s->last_mv[0][1][1] = 0; } else { /* if B type, reuse previous vectors and directions */ s->mv[0][0][0] = s->last_mv[0][0][0]; s->mv[0][0][1] = s->last_mv[0][0][1]; s->mv[1][0][0] = s->last_mv[1][0][0]; s->mv[1][0][1] = s->last_mv[1][0][1]; } s->mb_skiped = 1; return 0; } switch(s->pict_type) { default: case I_TYPE: if (get_bits1(&s->gb) == 0) { if (get_bits1(&s->gb) == 0) return -1; mb_type = MB_QUANT | MB_INTRA; } else { mb_type = MB_INTRA; } break; case P_TYPE: mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1); if (mb_type < 0){ fprintf(stderr, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y); return -1; } break; case B_TYPE: mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1); if (mb_type < 0){ fprintf(stderr, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y); return -1; } break; } dprintf("mb_type=%x\n", mb_type); motion_type = 0; /* avoid warning */ if (mb_type & (MB_FOR|MB_BACK)) { /* get additionnal motion vector type */ if (s->picture_structure == PICT_FRAME && s->frame_pred_frame_dct) motion_type = MT_FRAME; else motion_type = get_bits(&s->gb, 2); } /* compute dct type */ if (s->picture_structure == PICT_FRAME && !s->frame_pred_frame_dct && (mb_type & (MB_PAT | MB_INTRA))) { s->interlaced_dct = get_bits1(&s->gb); #ifdef DEBUG if (s->interlaced_dct) printf("interlaced_dct\n"); #endif } else { s->interlaced_dct = 0; /* frame based */ } if (mb_type & MB_QUANT) { s->qscale = get_qscale(s); } if (mb_type & MB_INTRA) { if (s->concealment_motion_vectors) { /* just parse them */ if (s->picture_structure != PICT_FRAME) skip_bits1(&s->gb); /* field select */ mpeg_decode_motion(s, s->mpeg_f_code[0][0], 0); mpeg_decode_motion(s, s->mpeg_f_code[0][1], 0); } s->mb_intra = 1; cbp = 0x3f; memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */ } else { s->mb_intra = 0; cbp = 0; } /* special case of implicit zero motion vector */ if (s->pict_type == P_TYPE && !(mb_type & MB_FOR)) { s->mv_dir = MV_DIR_FORWARD; s->mv_type = MV_TYPE_16X16; 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 if (mb_type & (MB_FOR | MB_BACK)) { /* motion vectors */ s->mv_dir = 0; for(i=0;i<2;i++) { if (mb_type & (MB_FOR >> i)) { s->mv_dir |= (MV_DIR_FORWARD >> i); dprintf("motion_type=%d\n", motion_type); switch(motion_type) { case MT_FRAME: /* or MT_16X8 */ if (s->picture_structure == PICT_FRAME) { /* MT_FRAME */ s->mv_type = MV_TYPE_16X16; for(k=0;k<2;k++) { val = mpeg_decode_motion(s, s->mpeg_f_code[i][k], s->last_mv[i][0][k]); s->last_mv[i][0][k] = val; s->last_mv[i][1][k] = val; /* full_pel: only for mpeg1 */ if (s->full_pel[i]) val = val << 1; s->mv[i][0][k] = val; dprintf("mv%d: %d\n", k, val); } } else { /* MT_16X8 */ s->mv_type = MV_TYPE_16X8; for(j=0;j<2;j++) { s->field_select[i][j] = get_bits1(&s->gb); for(k=0;k<2;k++) { val = mpeg_decode_motion(s, s->mpeg_f_code[i][k], s->last_mv[i][j][k]); s->last_mv[i][j][k] = val; s->mv[i][j][k] = val; } } } break; case MT_FIELD: if (s->picture_structure == PICT_FRAME) { s->mv_type = MV_TYPE_FIELD; for(j=0;j<2;j++) { s->field_select[i][j] = get_bits1(&s->gb); val = mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][j][0]); s->last_mv[i][j][0] = val; s->mv[i][j][0] = val; dprintf("fmx=%d\n", val); val = mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][j][1] >> 1); s->last_mv[i][j][1] = val << 1; s->mv[i][j][1] = val; dprintf("fmy=%d\n", val); } } else { s->mv_type = MV_TYPE_16X16; s->field_select[i][0] = get_bits1(&s->gb); for(k=0;k<2;k++) { val = mpeg_decode_motion(s, s->mpeg_f_code[i][k], s->last_mv[i][0][k]); s->last_mv[i][0][k] = val; s->last_mv[i][1][k] = val; s->mv[i][0][k] = val; } } break; case MT_DMV: { int dmx, dmy, mx, my, m; mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][0][0]); s->last_mv[i][0][0] = mx; s->last_mv[i][1][0] = mx; dmx = get_dmv(s); my = mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][0][1] >> 1); dmy = get_dmv(s); s->mv_type = MV_TYPE_DMV; /* XXX: totally broken */ if (s->picture_structure == PICT_FRAME) { s->last_mv[i][0][1] = my << 1; s->last_mv[i][1][1] = my << 1; m = s->top_field_first ? 1 : 3; /* top -> top pred */ s->mv[i][0][0] = mx; s->mv[i][0][1] = my << 1; s->mv[i][1][0] = ((mx * m + (mx > 0)) >> 1) + dmx; s->mv[i][1][1] = ((my * m + (my > 0)) >> 1) + dmy - 1; m = 4 - m; s->mv[i][2][0] = mx; s->mv[i][2][1] = my << 1; s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx; s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1; } else { s->last_mv[i][0][1] = my; s->last_mv[i][1][1] = my; s->mv[i][0][0] = mx; s->mv[i][0][1] = my; s->mv[i][1][0] = ((mx + (mx > 0)) >> 1) + dmx; s->mv[i][1][1] = ((my + (my > 0)) >> 1) + dmy - 1 /* + 2 * cur_field */; } } break; } } } } if ((mb_type & MB_INTRA) && s->concealment_motion_vectors) { skip_bits1(&s->gb); /* marker */ } if (mb_type & MB_PAT) { cbp = get_vlc2(&s->gb, mb_pat_vlc.table, MB_PAT_VLC_BITS, 1); if (cbp < 0){ fprintf(stderr, "invalid cbp at %d %d\n", s->mb_x, s->mb_y); return -1; } cbp++; } dprintf("cbp=%x\n", cbp); if (s->mpeg2) { if (s->mb_intra) { for(i=0;i<6;i++) { if (mpeg2_decode_block_intra(s, block[i], i) < 0) return -1; } } else { for(i=0;i<6;i++) { if (cbp & 32) { if (mpeg2_decode_block_non_intra(s, block[i], i) < 0) return -1; } else { s->block_last_index[i] = -1; } cbp+=cbp; } } } else { if (s->mb_intra) { for(i=0;i<6;i++) { if (mpeg1_decode_block_intra(s, block[i], i) < 0) return -1; } }else{ for(i=0;i<6;i++) { if (cbp & 32) { if (mpeg1_decode_block_inter(s, block[i], i) < 0) return -1; } else { s->block_last_index[i] = -1; } cbp+=cbp; } } } return 0; } /* as h263, but only 17 codes */ static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred) { int code, sign, val, m, l, shift; code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2); if (code < 0) { return 0xffff; } if (code == 0) { return pred; } sign = get_bits1(&s->gb); shift = fcode - 1; val = (code - 1) << shift; if (shift > 0) val |= get_bits(&s->gb, shift); val++; if (sign) val = -val; val += pred; /* modulo decoding */ l = (1 << shift) * 16; m = 2 * l; if (val < -l) { val += m; } else if (val >= l) { val -= m; } return val; } static inline int decode_dc(MpegEncContext *s, int component) { int code, diff; if (component == 0) { code = get_vlc2(&s->gb, dc_lum_vlc.table, DC_VLC_BITS, 2); } else { code = get_vlc2(&s->gb, dc_chroma_vlc.table, DC_VLC_BITS, 2); } if (code < 0){ fprintf(stderr, "invalid dc code at %d %d\n", s->mb_x, s->mb_y); return 0xffff; } if (code == 0) { diff = 0; } else { diff = get_bits(&s->gb, code); if ((diff & (1 << (code - 1))) == 0) diff = (-1 << code) | (diff + 1); } return diff; } static inline int mpeg1_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n) { int level, dc, diff, i, j, run; int component; RLTable *rl = &rl_mpeg1; UINT8 * const scantable= s->intra_scantable.permutated; const UINT16 *quant_matrix= s->intra_matrix; const int qscale= s->qscale; /* DC coef */ component = (n <= 3 ? 0 : n - 4 + 1); diff = decode_dc(s, component); if (diff >= 0xffff) return -1; dc = s->last_dc[component]; dc += diff; s->last_dc[component] = dc; block[0] = dc<<3; dprintf("dc=%d diff=%d\n", dc, diff); i = 0; { OPEN_READER(re, &s->gb); /* now quantify & encode AC coefs */ for(;;) { UPDATE_CACHE(re, &s->gb); GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2); if(level == 127){ break; } else if(level != 0) { i += run; j = scantable[i]; level= (level*qscale*quant_matrix[j])>>3; level= (level-1)|1; level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1); LAST_SKIP_BITS(re, &s->gb, 1); } else { /* escape */ run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6); UPDATE_CACHE(re, &s->gb); level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8); if (level == -128) { level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8); } else if (level == 0) { level = SHOW_UBITS(re, &s->gb, 8) ; LAST_SKIP_BITS(re, &s->gb, 8); } i += run; j = scantable[i]; if(level<0){ level= -level; level= (level*qscale*quant_matrix[j])>>3; level= (level-1)|1; level= -level; }else{ level= (level*qscale*quant_matrix[j])>>3; level= (level-1)|1; } } if (i > 63){ fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y); return -1; } block[j] = level; } CLOSE_READER(re, &s->gb); } s->block_last_index[n] = i; return 0; } static inline int mpeg1_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n) { int level, i, j, run; RLTable *rl = &rl_mpeg1; UINT8 * const scantable= s->intra_scantable.permutated; const UINT16 *quant_matrix= s->inter_matrix; const int qscale= s->qscale; { int v; OPEN_READER(re, &s->gb); i = -1; /* special case for the first coef. no need to add a second vlc table */ UPDATE_CACHE(re, &s->gb); v= SHOW_UBITS(re, &s->gb, 2); if (v & 2) { LAST_SKIP_BITS(re, &s->gb, 2); level= (3*qscale*quant_matrix[0])>>4; level= (level-1)|1; if(v&1) level= -level; block[0] = level; i++; } /* now quantify & encode AC coefs */ for(;;) { UPDATE_CACHE(re, &s->gb); GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2); if(level == 127){ break; } else if(level != 0) { i += run; j = scantable[i]; level= ((level*2+1)*qscale*quant_matrix[j])>>4; level= (level-1)|1; level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1); LAST_SKIP_BITS(re, &s->gb, 1); } else { /* escape */ run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6); UPDATE_CACHE(re, &s->gb); level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8); if (level == -128) { level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8); } else if (level == 0) { level = SHOW_UBITS(re, &s->gb, 8) ; LAST_SKIP_BITS(re, &s->gb, 8); } i += run; j = scantable[i]; if(level<0){ level= -level; level= ((level*2+1)*qscale*quant_matrix[j])>>4; level= (level-1)|1; level= -level; }else{ level= ((level*2+1)*qscale*quant_matrix[j])>>4; level= (level-1)|1; } } if (i > 63){ fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y); return -1; } block[j] = level; } CLOSE_READER(re, &s->gb); } s->block_last_index[n] = i; return 0; } /* Also does unquantization here, since I will never support mpeg2 encoding */ static inline int mpeg2_decode_block_non_intra(MpegEncContext *s, DCTELEM *block, int n) { int level, i, j, run; RLTable *rl = &rl_mpeg1; UINT8 * const scantable= s->intra_scantable.permutated; const UINT16 *quant_matrix; const int qscale= s->qscale; int mismatch; mismatch = 1; { int v; OPEN_READER(re, &s->gb); i = -1; if (n < 4) quant_matrix = s->inter_matrix; else quant_matrix = s->chroma_inter_matrix; /* special case for the first coef. no need to add a second vlc table */ UPDATE_CACHE(re, &s->gb); v= SHOW_UBITS(re, &s->gb, 2); if (v & 2) { LAST_SKIP_BITS(re, &s->gb, 2); level= (3*qscale*quant_matrix[0])>>5; if(v&1) level= -level; block[0] = level; mismatch ^= level; i++; } /* now quantify & encode AC coefs */ for(;;) { UPDATE_CACHE(re, &s->gb); GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2); if(level == 127){ break; } else if(level != 0) { i += run; j = scantable[i]; level= ((level*2+1)*qscale*quant_matrix[j])>>5; level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1); LAST_SKIP_BITS(re, &s->gb, 1); } else { /* escape */ run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6); UPDATE_CACHE(re, &s->gb); level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12); i += run; j = scantable[i]; if(level<0){ level= ((-level*2+1)*qscale*quant_matrix[j])>>5; level= -level; }else{ level= ((level*2+1)*qscale*quant_matrix[j])>>5; } } if (i > 63){ fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y); return -1; } mismatch ^= level; block[j] = level; } CLOSE_READER(re, &s->gb); } block[63] ^= (mismatch & 1); s->block_last_index[n] = i; return 0; } static inline int mpeg2_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n) { int level, dc, diff, i, j, run; int component; RLTable *rl; UINT8 * const scantable= s->intra_scantable.permutated; const UINT16 *quant_matrix; const int qscale= s->qscale; int mismatch; /* DC coef */ if (n < 4){ quant_matrix = s->intra_matrix; component = 0; }else{ quant_matrix = s->chroma_intra_matrix; component = n - 3; } diff = decode_dc(s, component); if (diff >= 0xffff) return -1; dc = s->last_dc[component]; dc += diff; s->last_dc[component] = dc; block[0] = dc << (3 - s->intra_dc_precision); dprintf("dc=%d\n", block[0]); mismatch = block[0] ^ 1; i = 0; if (s->intra_vlc_format) rl = &rl_mpeg2; else rl = &rl_mpeg1; { OPEN_READER(re, &s->gb); /* now quantify & encode AC coefs */ for(;;) { UPDATE_CACHE(re, &s->gb); GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2); if(level == 127){ break; } else if(level != 0) { i += run; j = scantable[i]; level= (level*qscale*quant_matrix[j])>>4; level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1); LAST_SKIP_BITS(re, &s->gb, 1); } else { /* escape */ run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6); UPDATE_CACHE(re, &s->gb); level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12); i += run; j = scantable[i]; if(level<0){ level= (-level*qscale*quant_matrix[j])>>4; level= -level; }else{ level= (level*qscale*quant_matrix[j])>>4; } } if (i > 63){ fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y); return -1; } mismatch^= level; block[j] = level; } CLOSE_READER(re, &s->gb); } block[63]^= mismatch&1; s->block_last_index[n] = i; return 0; } /* compressed picture size */ #define PICTURE_BUFFER_SIZE 100000 typedef struct Mpeg1Context { MpegEncContext mpeg_enc_ctx; UINT32 header_state; int start_code; /* current start code */ UINT8 buffer[PICTURE_BUFFER_SIZE]; UINT8 *buf_ptr; int buffer_size; int mpeg_enc_ctx_allocated; /* true if decoding context allocated */ int repeat_field; /* true if we must repeat the field */ } Mpeg1Context; static int mpeg_decode_init(AVCodecContext *avctx) { Mpeg1Context *s = avctx->priv_data; s->mpeg_enc_ctx.flags= avctx->flags; common_init(&s->mpeg_enc_ctx); init_vlcs(&s->mpeg_enc_ctx); s->header_state = 0xff; s->mpeg_enc_ctx_allocated = 0; s->buffer_size = PICTURE_BUFFER_SIZE; s->start_code = -1; s->buf_ptr = s->buffer; s->mpeg_enc_ctx.picture_number = 0; s->repeat_field = 0; s->mpeg_enc_ctx.codec_id= avctx->codec->id; return 0; } /* return the 8 bit start code value and update the search state. Return -1 if no start code found */ static int find_start_code(UINT8 **pbuf_ptr, UINT8 *buf_end, UINT32 *header_state) { UINT8 *buf_ptr; unsigned int state, v; int val; state = *header_state; buf_ptr = *pbuf_ptr; while (buf_ptr < buf_end) { v = *buf_ptr++; if (state == 0x000001) { state = ((state << 8) | v) & 0xffffff; val = state; goto found; } state = ((state << 8) | v) & 0xffffff; } val = -1; found: *pbuf_ptr = buf_ptr; *header_state = state; return val; } static int mpeg1_decode_picture(AVCodecContext *avctx, UINT8 *buf, int buf_size) { Mpeg1Context *s1 = avctx->priv_data; MpegEncContext *s = &s1->mpeg_enc_ctx; int ref, f_code; init_get_bits(&s->gb, buf, buf_size); ref = get_bits(&s->gb, 10); /* temporal ref */ s->pict_type = get_bits(&s->gb, 3); dprintf("pict_type=%d number=%d\n", s->pict_type, s->picture_number); skip_bits(&s->gb, 16); if (s->pict_type == P_TYPE || s->pict_type == B_TYPE) { s->full_pel[0] = get_bits1(&s->gb); f_code = get_bits(&s->gb, 3); if (f_code == 0) return -1; s->mpeg_f_code[0][0] = f_code; s->mpeg_f_code[0][1] = f_code; } if (s->pict_type == B_TYPE) { s->full_pel[1] = get_bits1(&s->gb); f_code = get_bits(&s->gb, 3); if (f_code == 0) return -1; s->mpeg_f_code[1][0] = f_code; s->mpeg_f_code[1][1] = f_code; } s->current_picture.pict_type= s->pict_type; s->current_picture.key_frame= s->pict_type == I_TYPE; s->y_dc_scale = 8; s->c_dc_scale = 8; s->first_slice = 1; return 0; } static void mpeg_decode_sequence_extension(MpegEncContext *s) { int horiz_size_ext, vert_size_ext; int bit_rate_ext, vbv_buf_ext, low_delay; int frame_rate_ext_n, frame_rate_ext_d; skip_bits(&s->gb, 8); /* profil and level */ s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */ skip_bits(&s->gb, 2); /* chroma_format */ horiz_size_ext = get_bits(&s->gb, 2); vert_size_ext = get_bits(&s->gb, 2); s->width |= (horiz_size_ext << 12); s->height |= (vert_size_ext << 12); bit_rate_ext = get_bits(&s->gb, 12); /* XXX: handle it */ s->bit_rate = ((s->bit_rate / 400) | (bit_rate_ext << 12)) * 400; skip_bits1(&s->gb); /* marker */ vbv_buf_ext = get_bits(&s->gb, 8); low_delay = get_bits1(&s->gb); frame_rate_ext_n = get_bits(&s->gb, 2); frame_rate_ext_d = get_bits(&s->gb, 5); if (frame_rate_ext_d >= 1) s->frame_rate = (s->frame_rate * frame_rate_ext_n) / frame_rate_ext_d; dprintf("sequence extension\n"); s->mpeg2 = 1; s->avctx->sub_id = 2; /* indicates mpeg2 found */ } static void mpeg_decode_quant_matrix_extension(MpegEncContext *s) { int i, v, j; dprintf("matrix extension\n"); if (get_bits1(&s->gb)) { for(i=0;i<64;i++) { v = get_bits(&s->gb, 8); j= s->idct_permutation[ ff_zigzag_direct[i] ]; s->intra_matrix[j] = v; s->chroma_intra_matrix[j] = v; } } if (get_bits1(&s->gb)) { for(i=0;i<64;i++) { v = get_bits(&s->gb, 8); j= s->idct_permutation[ ff_zigzag_direct[i] ]; s->inter_matrix[j] = v; s->chroma_inter_matrix[j] = v; } } if (get_bits1(&s->gb)) { for(i=0;i<64;i++) { v = get_bits(&s->gb, 8); j= s->idct_permutation[ ff_zigzag_direct[i] ]; s->chroma_intra_matrix[j] = v; } } if (get_bits1(&s->gb)) { for(i=0;i<64;i++) { v = get_bits(&s->gb, 8); j= s->idct_permutation[ ff_zigzag_direct[i] ]; s->chroma_inter_matrix[j] = v; } } } static void mpeg_decode_picture_coding_extension(MpegEncContext *s) { s->full_pel[0] = s->full_pel[1] = 0; s->mpeg_f_code[0][0] = get_bits(&s->gb, 4); s->mpeg_f_code[0][1] = get_bits(&s->gb, 4); s->mpeg_f_code[1][0] = get_bits(&s->gb, 4); s->mpeg_f_code[1][1] = get_bits(&s->gb, 4); s->intra_dc_precision = get_bits(&s->gb, 2); s->picture_structure = get_bits(&s->gb, 2); s->top_field_first = get_bits1(&s->gb); s->frame_pred_frame_dct = get_bits1(&s->gb); s->concealment_motion_vectors = get_bits1(&s->gb); s->q_scale_type = get_bits1(&s->gb); s->intra_vlc_format = get_bits1(&s->gb); s->alternate_scan = get_bits1(&s->gb); s->repeat_first_field = get_bits1(&s->gb); s->chroma_420_type = get_bits1(&s->gb); s->progressive_frame = get_bits1(&s->gb); if(s->alternate_scan){ ff_init_scantable(s, &s->inter_scantable , ff_alternate_vertical_scan); ff_init_scantable(s, &s->intra_scantable , ff_alternate_vertical_scan); ff_init_scantable(s, &s->intra_h_scantable, ff_alternate_vertical_scan); ff_init_scantable(s, &s->intra_v_scantable, ff_alternate_vertical_scan); }else{ ff_init_scantable(s, &s->inter_scantable , ff_zigzag_direct); ff_init_scantable(s, &s->intra_scantable , ff_zigzag_direct); ff_init_scantable(s, &s->intra_h_scantable, ff_alternate_horizontal_scan); ff_init_scantable(s, &s->intra_v_scantable, ff_alternate_vertical_scan); } /* composite display not parsed */ dprintf("intra_dc_precision=%d\n", s->intra_dc_precision); dprintf("picture_structure=%d\n", s->picture_structure); dprintf("top field first=%d\n", s->top_field_first); dprintf("repeat first field=%d\n", s->repeat_first_field); dprintf("conceal=%d\n", s->concealment_motion_vectors); dprintf("intra_vlc_format=%d\n", s->intra_vlc_format); dprintf("alternate_scan=%d\n", s->alternate_scan); dprintf("frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct); dprintf("progressive_frame=%d\n", s->progressive_frame); } static void mpeg_decode_extension(AVCodecContext *avctx, UINT8 *buf, int buf_size) { Mpeg1Context *s1 = avctx->priv_data; MpegEncContext *s = &s1->mpeg_enc_ctx; int ext_type; init_get_bits(&s->gb, buf, buf_size); ext_type = get_bits(&s->gb, 4); switch(ext_type) { case 0x1: /* sequence ext */ mpeg_decode_sequence_extension(s); break; case 0x3: /* quant matrix extension */ mpeg_decode_quant_matrix_extension(s); break; case 0x8: /* picture extension */ mpeg_decode_picture_coding_extension(s); break; } } #define DECODE_SLICE_FATAL_ERROR -2 #define DECODE_SLICE_ERROR -1 #define DECODE_SLICE_OK 0 #define DECODE_SLICE_EOP 1 /** * decodes a slice. * @return DECODE_SLICE_FATAL_ERROR if a non recoverable error occured<br> * DECODE_SLICE_ERROR if the slice is damaged<br> * DECODE_SLICE_OK if this slice is ok<br> * DECODE_SLICE_EOP if the end of the picture is reached */ static int mpeg_decode_slice(AVCodecContext *avctx, AVVideoFrame *pict, int start_code, UINT8 *buf, int buf_size) { Mpeg1Context *s1 = avctx->priv_data; MpegEncContext *s = &s1->mpeg_enc_ctx; int ret; start_code = (start_code - 1) & 0xff; if (start_code >= s->mb_height){ fprintf(stderr, "slice below image (%d >= %d)\n", start_code, s->mb_height); return DECODE_SLICE_ERROR; } 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)); /* start frame decoding */ if (s->first_slice) { s->first_slice = 0; if(MPV_frame_start(s, avctx) < 0) return DECODE_SLICE_FATAL_ERROR; } init_get_bits(&s->gb, buf, buf_size); s->qscale = get_qscale(s); /* extra slice info */ while (get_bits1(&s->gb) != 0) { skip_bits(&s->gb, 8); } s->mb_x=0; for(;;) { int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2); if (code < 0) return -1; /* error = end of slice, but empty slice is bad or?*/ if (code >= 33) { if (code == 33) { s->mb_x += 33; } /* otherwise, stuffing, nothing to do */ } else { s->mb_x += code; break; } } s->mb_y = start_code; s->mb_incr= 1; for(;;) { s->dsp.clear_blocks(s->block[0]); ret = mpeg_decode_mb(s, s->block); dprintf("ret=%d\n", ret); if (ret < 0) return -1; MPV_decode_mb(s, s->block); if (++s->mb_x >= s->mb_width) { ff_draw_horiz_band(s); s->mb_x = 0; s->mb_y++; PRINT_QP("%s", "\n"); } PRINT_QP("%2d", s->qscale); /* skip mb handling */ if (s->mb_incr == 0) { /* read again increment */ s->mb_incr = 1; for(;;) { int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2); if (code < 0) goto eos; /* error = end of slice */ if (code >= 33) { if (code == 33) { s->mb_incr += 33; } /* otherwise, stuffing, nothing to do */ } else { s->mb_incr += code; break; } } } if(s->mb_y >= s->mb_height){ fprintf(stderr, "slice too long\n"); return DECODE_SLICE_ERROR; } } eos: //end of slice emms_c(); /* end of slice reached */ if (/*s->mb_x == 0 &&*/ s->mb_y == s->mb_height) { /* end of image */ if(s->mpeg2) s->qscale >>=1; MPV_frame_end(s); if (s->pict_type == B_TYPE) { *pict= *(AVVideoFrame*)&s->current_picture; } else { s->picture_number++; /* latency of 1 frame for I and P frames */ /* XXX: use another variable than picture_number */ if (s->picture_number == 1) { return DECODE_SLICE_OK; } else { *pict= *(AVVideoFrame*)&s->last_picture; } } return DECODE_SLICE_EOP; } else { return DECODE_SLICE_OK; } } static int mpeg1_decode_sequence(AVCodecContext *avctx, UINT8 *buf, int buf_size) { Mpeg1Context *s1 = avctx->priv_data; MpegEncContext *s = &s1->mpeg_enc_ctx; int width, height, i, v, j; init_get_bits(&s->gb, buf, buf_size); width = get_bits(&s->gb, 12); height = get_bits(&s->gb, 12); skip_bits(&s->gb, 4); s->frame_rate_index = get_bits(&s->gb, 4); if (s->frame_rate_index == 0) return -1; s->bit_rate = get_bits(&s->gb, 18) * 400; if (get_bits1(&s->gb) == 0) /* marker */ return -1; if (width <= 0 || height <= 0 || (width % 2) != 0 || (height % 2) != 0) return -1; if (width != s->width || height != s->height) { /* start new mpeg1 context decoding */ s->out_format = FMT_MPEG1; if (s1->mpeg_enc_ctx_allocated) { MPV_common_end(s); } s->width = width; s->height = height; avctx->has_b_frames= s->has_b_frames = 1; s->avctx = avctx; avctx->width = width; avctx->height = height; if (s->frame_rate_index >= 9) { /* at least give a valid frame rate (some old mpeg1 have this) */ avctx->frame_rate = 25 * FRAME_RATE_BASE; } else { avctx->frame_rate = frame_rate_tab[s->frame_rate_index]; } s->frame_rate = avctx->frame_rate; avctx->bit_rate = s->bit_rate; if (MPV_common_init(s) < 0) return -1; s1->mpeg_enc_ctx_allocated = 1; } skip_bits(&s->gb, 10); /* vbv_buffer_size */ skip_bits(&s->gb, 1); /* get matrix */ if (get_bits1(&s->gb)) { for(i=0;i<64;i++) { v = get_bits(&s->gb, 8); j = s->intra_scantable.permutated[i]; s->intra_matrix[j] = v; s->chroma_intra_matrix[j] = v; } #ifdef DEBUG dprintf("intra matrix present\n"); for(i=0;i<64;i++) dprintf(" %d", s->intra_matrix[s->intra_scantable.permutated[i]]); printf("\n"); #endif } else { for(i=0;i<64;i++) { int j= s->idct_permutation[i]; v = ff_mpeg1_default_intra_matrix[i]; s->intra_matrix[j] = v; s->chroma_intra_matrix[j] = v; } } if (get_bits1(&s->gb)) { for(i=0;i<64;i++) { v = get_bits(&s->gb, 8); j = s->intra_scantable.permutated[i]; s->inter_matrix[j] = v; s->chroma_inter_matrix[j] = v; } #ifdef DEBUG dprintf("non intra matrix present\n"); for(i=0;i<64;i++) dprintf(" %d", s->inter_matrix[s->intra_scantable.permutated[i]]); printf("\n"); #endif } else { for(i=0;i<64;i++) { int j= s->idct_permutation[i]; v = ff_mpeg1_default_non_intra_matrix[i]; s->inter_matrix[j] = v; s->chroma_inter_matrix[j] = v; } } /* we set mpeg2 parameters so that it emulates mpeg1 */ s->progressive_sequence = 1; s->progressive_frame = 1; s->picture_structure = PICT_FRAME; s->frame_pred_frame_dct = 1; s->mpeg2 = 0; avctx->sub_id = 1; /* indicates mpeg1 */ return 0; } /* handle buffering and image synchronisation */ static int mpeg_decode_frame(AVCodecContext *avctx, void *data, int *data_size, UINT8 *buf, int buf_size) { Mpeg1Context *s = avctx->priv_data; UINT8 *buf_end, *buf_ptr, *buf_start; int len, start_code_found, ret, code, start_code, input_size; AVVideoFrame *picture = data; MpegEncContext *s2 = &s->mpeg_enc_ctx; dprintf("fill_buffer\n"); *data_size = 0; /* special case for last picture */ if (buf_size == 0) { if (s2->picture_number > 0) { *picture= *(AVVideoFrame*)&s2->next_picture; *data_size = sizeof(AVVideoFrame); } return 0; } buf_ptr = buf; buf_end = buf + buf_size; #if 0 if (s->repeat_field % 2 == 1) { s->repeat_field++; //fprintf(stderr,"\nRepeating last frame: %d -> %d! pict: %d %d", avctx->frame_number-1, avctx->frame_number, // s2->picture_number, s->repeat_field); if (avctx->flags & CODEC_FLAG_REPEAT_FIELD) { *data_size = sizeof(AVPicture); goto the_end; } } #endif while (buf_ptr < buf_end) { buf_start = buf_ptr; /* find start next code */ code = find_start_code(&buf_ptr, buf_end, &s->header_state); if (code >= 0) { start_code_found = 1; } else { start_code_found = 0; } /* copy to buffer */ len = buf_ptr - buf_start; if (len + (s->buf_ptr - s->buffer) > s->buffer_size) { /* data too big : flush */ s->buf_ptr = s->buffer; if (start_code_found) s->start_code = code; } else { memcpy(s->buf_ptr, buf_start, len); s->buf_ptr += len; if( (!(s2->flags&CODEC_FLAG_TRUNCATED)) && (!start_code_found) && s->buf_ptr+4<s->buffer+s->buffer_size){ start_code_found= 1; code= 0x1FF; s->header_state=0xFF; s->buf_ptr[0]=0; s->buf_ptr[1]=0; s->buf_ptr[2]=1; s->buf_ptr[3]=0xFF; s->buf_ptr+=4; } if (start_code_found) { /* prepare data for next start code */ input_size = s->buf_ptr - s->buffer; start_code = s->start_code; s->buf_ptr = s->buffer; s->start_code = code; switch(start_code) { case SEQ_START_CODE: mpeg1_decode_sequence(avctx, s->buffer, input_size); break; case PICTURE_START_CODE: /* we have a complete image : we try to decompress it */ mpeg1_decode_picture(avctx, s->buffer, input_size); break; case EXT_START_CODE: mpeg_decode_extension(avctx, s->buffer, input_size); break; default: if (start_code >= SLICE_MIN_START_CODE && start_code <= SLICE_MAX_START_CODE && avctx->hurry_up<5) { ret = mpeg_decode_slice(avctx, picture, start_code, s->buffer, input_size); if (ret == DECODE_SLICE_EOP) { /* got a picture: exit */ /* first check if we must repeat the frame */ avctx->repeat_pict = 0; #if 0 if (s2->progressive_frame && s2->repeat_first_field) { //fprintf(stderr,"\nRepeat this frame: %d! pict: %d",avctx->frame_number,s2->picture_number); //s2->repeat_first_field = 0; //s2->progressive_frame = 0; if (++s->repeat_field > 2) s->repeat_field = 0; avctx->repeat_pict = 1; } #endif if (s2->repeat_first_field) { if (s2->progressive_sequence) { if (s2->top_field_first) avctx->repeat_pict = 4; else avctx->repeat_pict = 2; } else if (s2->progressive_frame) { avctx->repeat_pict = 1; } } *data_size = sizeof(AVPicture); goto the_end; }else if(ret<0){ fprintf(stderr,"Error while decoding slice\n"); if(ret==DECODE_SLICE_FATAL_ERROR) return -1; } } break; } } } } the_end: return buf_ptr - buf; } static int mpeg_decode_end(AVCodecContext *avctx) { Mpeg1Context *s = avctx->priv_data; if (s->mpeg_enc_ctx_allocated) MPV_common_end(&s->mpeg_enc_ctx); return 0; } AVCodec mpeg_decoder = { "mpegvideo", CODEC_TYPE_VIDEO, CODEC_ID_MPEG1VIDEO, sizeof(Mpeg1Context), mpeg_decode_init, NULL, mpeg_decode_end, mpeg_decode_frame, CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED, };