diff options
author | Kostya Shishkov <kostya.shishkov@gmail.com> | 2007-12-04 20:41:46 +0300 |
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committer | Kostya Shishkov <kostya.shishkov@gmail.com> | 2007-12-04 20:41:46 +0300 |
commit | ae4ca617e3b36132cb077bf0e89dbb5220a053ae (patch) | |
tree | a871e9be293e9fc78ff42091b3b1399640dd7fbf /libavcodec/rv40.c | |
parent | c1da59fa2d9ff701655d94fede63d0e645948a54 (diff) |
RV40 decoder specific functions
Originally committed as revision 11163 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec/rv40.c')
-rw-r--r-- | libavcodec/rv40.c | 275 |
1 files changed, 275 insertions, 0 deletions
diff --git a/libavcodec/rv40.c b/libavcodec/rv40.c new file mode 100644 index 0000000000..791ed17901 --- /dev/null +++ b/libavcodec/rv40.c @@ -0,0 +1,275 @@ +/* + * 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 "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); + 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, int *dst) +{ + MpegEncContext *s = &r->s; + int i, j, k, v; + int A, B, C; + int pattern; + int *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 = ff_rv34_get_gamma(gb); + + if(--r->s.mb_skip_run) + return RV34_MB_SKIP; + + if(r->avail[0]) + blocks[r->mb_type[mb_pos - 1]]++; + if(r->avail[1]){ + blocks[r->mb_type[mb_pos - s->mb_stride]]++; + if(r->avail[2]) + blocks[r->mb_type[mb_pos - s->mb_stride + 1]]++; + if(r->avail[3]) + 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, +}; |