/* * RV40 decoder * Copyright (c) 2007 Konstantin Shishkov * * 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 rv40.c * RV40 decoder */ #include "avcodec.h" #include "dsputil.h" #include "mpegvideo.h" #include "golomb.h" #include "rv34.h" #include "rv40vlc2.h" #include "rv40data.h" static VLC aic_top_vlc; static VLC aic_mode1_vlc[AIC_MODE1_NUM], aic_mode2_vlc[AIC_MODE2_NUM]; static VLC ptype_vlc[NUM_PTYPE_VLCS], btype_vlc[NUM_BTYPE_VLCS]; /** * Initialize all tables. */ static void rv40_init_tables() { int i; init_vlc(&aic_top_vlc, AIC_TOP_BITS, AIC_TOP_SIZE, rv40_aic_top_vlc_bits, 1, 1, rv40_aic_top_vlc_codes, 1, 1, INIT_VLC_USE_STATIC); for(i = 0; i < AIC_MODE1_NUM; i++){ // Every tenth VLC table is empty if((i % 10) == 9) continue; init_vlc(&aic_mode1_vlc[i], AIC_MODE1_BITS, AIC_MODE1_SIZE, aic_mode1_vlc_bits[i], 1, 1, aic_mode1_vlc_codes[i], 1, 1, INIT_VLC_USE_STATIC); } for(i = 0; i < AIC_MODE2_NUM; i++){ init_vlc(&aic_mode2_vlc[i], AIC_MODE2_BITS, AIC_MODE2_SIZE, aic_mode2_vlc_bits[i], 1, 1, aic_mode2_vlc_codes[i], 2, 2, INIT_VLC_USE_STATIC); } for(i = 0; i < NUM_PTYPE_VLCS; i++) init_vlc_sparse(&ptype_vlc[i], PTYPE_VLC_BITS, PTYPE_VLC_SIZE, ptype_vlc_bits[i], 1, 1, ptype_vlc_codes[i], 1, 1, ptype_vlc_syms, 1, 1, INIT_VLC_USE_STATIC); for(i = 0; i < NUM_BTYPE_VLCS; i++) init_vlc_sparse(&btype_vlc[i], BTYPE_VLC_BITS, BTYPE_VLC_SIZE, btype_vlc_bits[i], 1, 1, btype_vlc_codes[i], 1, 1, btype_vlc_syms, 1, 1, INIT_VLC_USE_STATIC); } /** * Get stored dimension from bitstream. * * If the width/height is the standard one then it's coded as a 3-bit index. * Otherwise it is coded as escaped 8-bit portions. */ static int get_dimension(GetBitContext *gb, const int *dim) { int t = get_bits(gb, 3); int val = dim[t]; if(val < 0) val = dim[get_bits1(gb) - val]; if(!val){ do{ t = get_bits(gb, 8); val += t << 2; }while(t == 0xFF); } return val; } /** * Get encoded picture size - usually this is called from rv40_parse_slice_header. */ static void rv40_parse_picture_size(GetBitContext *gb, int *w, int *h) { *w = get_dimension(gb, rv40_standard_widths); *h = get_dimension(gb, rv40_standard_heights); } static int rv40_parse_slice_header(RV34DecContext *r, GetBitContext *gb, SliceInfo *si) { int t, mb_bits; int w = r->s.width, h = r->s.height; int mb_size; memset(si, 0, sizeof(SliceInfo)); if(get_bits1(gb)) return -1; si->type = get_bits(gb, 2); if(si->type == 1) si->type = 0; si->quant = get_bits(gb, 5); if(get_bits(gb, 2)) return -1; si->vlc_set = get_bits(gb, 2); skip_bits1(gb); t = get_bits(gb, 13); /// ??? if(!si->type || !get_bits1(gb)) rv40_parse_picture_size(gb, &w, &h); if(avcodec_check_dimensions(r->s.avctx, w, h) < 0) return -1; si->width = w; si->height = h; mb_size = ((w + 15) >> 4) * ((h + 15) >> 4); mb_bits = ff_rv34_get_start_offset(gb, mb_size); si->start = get_bits(gb, mb_bits); return 0; } /** * Decode 4x4 intra types array. */ static int rv40_decode_intra_types(RV34DecContext *r, GetBitContext *gb, int8_t *dst) { MpegEncContext *s = &r->s; int i, j, k, v; int A, B, C; int pattern; int8_t *ptr; for(i = 0; i < 4; i++, dst += s->b4_stride){ if(!i && s->first_slice_line){ pattern = get_vlc2(gb, aic_top_vlc.table, AIC_TOP_BITS, 1); dst[0] = (pattern >> 2) & 2; dst[1] = (pattern >> 1) & 2; dst[2] = pattern & 2; dst[3] = (pattern << 1) & 2; continue; } ptr = dst; for(j = 0; j < 4; j++){ /* Coefficients are read using VLC chosen by the prediction pattern * The first one (used for retrieving a pair of coefficients) is * constructed from the top, top right and left coefficients * The second one (used for retrieving only one coefficient) is * top + 10 * left. */ A = ptr[-s->b4_stride + 1]; // it won't be used for the last coefficient in a row B = ptr[-s->b4_stride]; C = ptr[-1]; pattern = A + (B << 4) + (C << 8); for(k = 0; k < MODE2_PATTERNS_NUM; k++) if(pattern == rv40_aic_table_index[k]) break; if(j < 3 && k < MODE2_PATTERNS_NUM){ //pattern is found, decoding 2 coefficients v = get_vlc2(gb, aic_mode2_vlc[k].table, AIC_MODE2_BITS, 2); *ptr++ = v/9; *ptr++ = v%9; j++; }else{ if(B != -1 && C != -1) v = get_vlc2(gb, aic_mode1_vlc[B + C*10].table, AIC_MODE1_BITS, 1); else{ // tricky decoding v = 0; switch(C){ case -1: // code 0 -> 1, 1 -> 0 if(B < 2) v = get_bits1(gb) ^ 1; break; case 0: case 2: // code 0 -> 2, 1 -> 0 v = (get_bits1(gb) ^ 1) << 1; break; } } *ptr++ = v; } } } return 0; } /** * Decode macroblock information. */ static int rv40_decode_mb_info(RV34DecContext *r) { MpegEncContext *s = &r->s; GetBitContext *gb = &s->gb; int q, i; int prev_type = 0; int mb_pos = s->mb_x + s->mb_y * s->mb_stride; int blocks[RV34_MB_TYPES] = {0}; int count = 0; if(!r->s.mb_skip_run) r->s.mb_skip_run = svq3_get_ue_golomb(gb) + 1; if(--r->s.mb_skip_run) return RV34_MB_SKIP; if(r->avail_cache[5-1]) blocks[r->mb_type[mb_pos - 1]]++; if(r->avail_cache[5-4]){ blocks[r->mb_type[mb_pos - s->mb_stride]]++; if(r->avail_cache[5-2]) blocks[r->mb_type[mb_pos - s->mb_stride + 1]]++; if(r->avail_cache[5-5]) blocks[r->mb_type[mb_pos - s->mb_stride - 1]]++; } for(i = 0; i < RV34_MB_TYPES; i++){ if(blocks[i] > count){ count = blocks[i]; prev_type = i; } } if(s->pict_type == P_TYPE){ prev_type = block_num_to_ptype_vlc_num[prev_type]; q = get_vlc2(gb, ptype_vlc[prev_type].table, PTYPE_VLC_BITS, 1); if(q < PBTYPE_ESCAPE) return q; q = get_vlc2(gb, ptype_vlc[prev_type].table, PTYPE_VLC_BITS, 1); av_log(s->avctx, AV_LOG_ERROR, "Dquant for P-frame\n"); }else{ prev_type = block_num_to_btype_vlc_num[prev_type]; q = get_vlc2(gb, btype_vlc[prev_type].table, BTYPE_VLC_BITS, 1); if(q < PBTYPE_ESCAPE) return q; q = get_vlc2(gb, btype_vlc[prev_type].table, BTYPE_VLC_BITS, 1); av_log(s->avctx, AV_LOG_ERROR, "Dquant for B-frame\n"); } return 0; } /** * Initialize decoder. */ static int rv40_decode_init(AVCodecContext *avctx) { RV34DecContext *r = avctx->priv_data; r->rv30 = 0; ff_rv34_decode_init(avctx); if(!aic_top_vlc.bits) rv40_init_tables(); r->parse_slice_header = rv40_parse_slice_header; r->decode_intra_types = rv40_decode_intra_types; r->decode_mb_info = rv40_decode_mb_info; r->luma_dc_quant_i = rv40_luma_dc_quant[0]; r->luma_dc_quant_p = rv40_luma_dc_quant[1]; return 0; } AVCodec rv40_decoder = { "rv40", CODEC_TYPE_VIDEO, CODEC_ID_RV40, sizeof(RV34DecContext), rv40_decode_init, NULL, ff_rv34_decode_end, ff_rv34_decode_frame, CODEC_CAP_DR1 | CODEC_CAP_DELAY, };