/** * @file libavcodec/vp6.c * VP6 compatible video decoder * * Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org> * * The VP6F decoder accepts an optional 1 byte extradata. It is composed of: * - upper 4bits: difference between encoded width and visible width * - lower 4bits: difference between encoded height and visible height * * 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 */ #include <stdlib.h> #include "avcodec.h" #include "dsputil.h" #include "bitstream.h" #include "huffman.h" #include "vp56.h" #include "vp56data.h" #include "vp6data.h" static void vp6_parse_coeff(VP56Context *s); static void vp6_parse_coeff_huffman(VP56Context *s); static int vp6_parse_header(VP56Context *s, const uint8_t *buf, int buf_size, int *golden_frame) { VP56RangeCoder *c = &s->c; int parse_filter_info = 0; int coeff_offset = 0; int vrt_shift = 0; int sub_version; int rows, cols; int res = 1; int separated_coeff = buf[0] & 1; s->framep[VP56_FRAME_CURRENT]->key_frame = !(buf[0] & 0x80); vp56_init_dequant(s, (buf[0] >> 1) & 0x3F); if (s->framep[VP56_FRAME_CURRENT]->key_frame) { sub_version = buf[1] >> 3; if (sub_version > 8) return 0; s->filter_header = buf[1] & 0x06; if (buf[1] & 1) { av_log(s->avctx, AV_LOG_ERROR, "interlacing not supported\n"); return 0; } if (separated_coeff || !s->filter_header) { coeff_offset = AV_RB16(buf+2) - 2; buf += 2; buf_size -= 2; } rows = buf[2]; /* number of stored macroblock rows */ cols = buf[3]; /* number of stored macroblock cols */ /* buf[4] is number of displayed macroblock rows */ /* buf[5] is number of displayed macroblock cols */ if (!s->macroblocks || /* first frame */ 16*cols != s->avctx->coded_width || 16*rows != s->avctx->coded_height) { avcodec_set_dimensions(s->avctx, 16*cols, 16*rows); if (s->avctx->extradata_size == 1) { s->avctx->width -= s->avctx->extradata[0] >> 4; s->avctx->height -= s->avctx->extradata[0] & 0x0F; } res = 2; } vp56_init_range_decoder(c, buf+6, buf_size-6); vp56_rac_gets(c, 2); parse_filter_info = s->filter_header; if (sub_version < 8) vrt_shift = 5; s->sub_version = sub_version; } else { if (!s->sub_version) return 0; if (separated_coeff || !s->filter_header) { coeff_offset = AV_RB16(buf+1) - 2; buf += 2; buf_size -= 2; } vp56_init_range_decoder(c, buf+1, buf_size-1); *golden_frame = vp56_rac_get(c); if (s->filter_header) { s->deblock_filtering = vp56_rac_get(c); if (s->deblock_filtering) vp56_rac_get(c); if (s->sub_version > 7) parse_filter_info = vp56_rac_get(c); } } if (parse_filter_info) { if (vp56_rac_get(c)) { s->filter_mode = 2; s->sample_variance_threshold = vp56_rac_gets(c, 5) << vrt_shift; s->max_vector_length = 2 << vp56_rac_gets(c, 3); } else if (vp56_rac_get(c)) { s->filter_mode = 1; } else { s->filter_mode = 0; } if (s->sub_version > 7) s->filter_selection = vp56_rac_gets(c, 4); else s->filter_selection = 16; } s->use_huffman = vp56_rac_get(c); s->parse_coeff = vp6_parse_coeff; if (coeff_offset) { buf += coeff_offset; buf_size -= coeff_offset; if (buf_size < 0) return 0; if (s->use_huffman) { s->parse_coeff = vp6_parse_coeff_huffman; init_get_bits(&s->gb, buf, buf_size<<3); } else { vp56_init_range_decoder(&s->cc, buf, buf_size); s->ccp = &s->cc; } } else { s->ccp = &s->c; } return res; } static void vp6_coeff_order_table_init(VP56Context *s) { int i, pos, idx = 1; s->modelp->coeff_index_to_pos[0] = 0; for (i=0; i<16; i++) for (pos=1; pos<64; pos++) if (s->modelp->coeff_reorder[pos] == i) s->modelp->coeff_index_to_pos[idx++] = pos; } static void vp6_default_models_init(VP56Context *s) { VP56Model *model = s->modelp; model->vector_dct[0] = 0xA2; model->vector_dct[1] = 0xA4; model->vector_sig[0] = 0x80; model->vector_sig[1] = 0x80; memcpy(model->mb_types_stats, vp56_def_mb_types_stats, sizeof(model->mb_types_stats)); memcpy(model->vector_fdv, vp6_def_fdv_vector_model, sizeof(model->vector_fdv)); memcpy(model->vector_pdv, vp6_def_pdv_vector_model, sizeof(model->vector_pdv)); memcpy(model->coeff_runv, vp6_def_runv_coeff_model, sizeof(model->coeff_runv)); memcpy(model->coeff_reorder, vp6_def_coeff_reorder, sizeof(model->coeff_reorder)); vp6_coeff_order_table_init(s); } static void vp6_parse_vector_models(VP56Context *s) { VP56RangeCoder *c = &s->c; VP56Model *model = s->modelp; int comp, node; for (comp=0; comp<2; comp++) { if (vp56_rac_get_prob(c, vp6_sig_dct_pct[comp][0])) model->vector_dct[comp] = vp56_rac_gets_nn(c, 7); if (vp56_rac_get_prob(c, vp6_sig_dct_pct[comp][1])) model->vector_sig[comp] = vp56_rac_gets_nn(c, 7); } for (comp=0; comp<2; comp++) for (node=0; node<7; node++) if (vp56_rac_get_prob(c, vp6_pdv_pct[comp][node])) model->vector_pdv[comp][node] = vp56_rac_gets_nn(c, 7); for (comp=0; comp<2; comp++) for (node=0; node<8; node++) if (vp56_rac_get_prob(c, vp6_fdv_pct[comp][node])) model->vector_fdv[comp][node] = vp56_rac_gets_nn(c, 7); } /* nodes must ascend by count, but with descending symbol order */ static int vp6_huff_cmp(const void *va, const void *vb) { const Node *a = va, *b = vb; return (a->count - b->count)*16 + (b->sym - a->sym); } static void vp6_build_huff_tree(VP56Context *s, uint8_t coeff_model[], const uint8_t *map, unsigned size, VLC *vlc) { Node nodes[2*size], *tmp = &nodes[size]; int a, b, i; /* first compute probabilities from model */ tmp[0].count = 256; for (i=0; i<size-1; i++) { a = tmp[i].count * coeff_model[i] >> 8; b = tmp[i].count * (255 - coeff_model[i]) >> 8; nodes[map[2*i ]].count = a + !a; nodes[map[2*i+1]].count = b + !b; } /* then build the huffman tree accodring to probabilities */ ff_huff_build_tree(s->avctx, vlc, size, nodes, vp6_huff_cmp, FF_HUFFMAN_FLAG_HNODE_FIRST); } static void vp6_parse_coeff_models(VP56Context *s) { VP56RangeCoder *c = &s->c; VP56Model *model = s->modelp; int def_prob[11]; int node, cg, ctx, pos; int ct; /* code type */ int pt; /* plane type (0 for Y, 1 for U or V) */ memset(def_prob, 0x80, sizeof(def_prob)); for (pt=0; pt<2; pt++) for (node=0; node<11; node++) if (vp56_rac_get_prob(c, vp6_dccv_pct[pt][node])) { def_prob[node] = vp56_rac_gets_nn(c, 7); model->coeff_dccv[pt][node] = def_prob[node]; } else if (s->framep[VP56_FRAME_CURRENT]->key_frame) { model->coeff_dccv[pt][node] = def_prob[node]; } if (vp56_rac_get(c)) { for (pos=1; pos<64; pos++) if (vp56_rac_get_prob(c, vp6_coeff_reorder_pct[pos])) model->coeff_reorder[pos] = vp56_rac_gets(c, 4); vp6_coeff_order_table_init(s); } for (cg=0; cg<2; cg++) for (node=0; node<14; node++) if (vp56_rac_get_prob(c, vp6_runv_pct[cg][node])) model->coeff_runv[cg][node] = vp56_rac_gets_nn(c, 7); for (ct=0; ct<3; ct++) for (pt=0; pt<2; pt++) for (cg=0; cg<6; cg++) for (node=0; node<11; node++) if (vp56_rac_get_prob(c, vp6_ract_pct[ct][pt][cg][node])) { def_prob[node] = vp56_rac_gets_nn(c, 7); model->coeff_ract[pt][ct][cg][node] = def_prob[node]; } else if (s->framep[VP56_FRAME_CURRENT]->key_frame) { model->coeff_ract[pt][ct][cg][node] = def_prob[node]; } if (s->use_huffman) { for (pt=0; pt<2; pt++) { vp6_build_huff_tree(s, model->coeff_dccv[pt], vp6_huff_coeff_map, 12, &s->dccv_vlc[pt]); vp6_build_huff_tree(s, model->coeff_runv[pt], vp6_huff_run_map, 9, &s->runv_vlc[pt]); for (ct=0; ct<3; ct++) for (cg = 0; cg < 6; cg++) vp6_build_huff_tree(s, model->coeff_ract[pt][ct][cg], vp6_huff_coeff_map, 12, &s->ract_vlc[pt][ct][cg]); } memset(s->nb_null, 0, sizeof(s->nb_null)); } else { /* coeff_dcct is a linear combination of coeff_dccv */ for (pt=0; pt<2; pt++) for (ctx=0; ctx<3; ctx++) for (node=0; node<5; node++) model->coeff_dcct[pt][ctx][node] = av_clip(((model->coeff_dccv[pt][node] * vp6_dccv_lc[ctx][node][0] + 128) >> 8) + vp6_dccv_lc[ctx][node][1], 1, 255); } } static void vp6_parse_vector_adjustment(VP56Context *s, VP56mv *vect) { VP56RangeCoder *c = &s->c; VP56Model *model = s->modelp; int comp; *vect = (VP56mv) {0,0}; if (s->vector_candidate_pos < 2) *vect = s->vector_candidate[0]; for (comp=0; comp<2; comp++) { int i, delta = 0; if (vp56_rac_get_prob(c, model->vector_dct[comp])) { static const uint8_t prob_order[] = {0, 1, 2, 7, 6, 5, 4}; for (i=0; i<sizeof(prob_order); i++) { int j = prob_order[i]; delta |= vp56_rac_get_prob(c, model->vector_fdv[comp][j])<<j; } if (delta & 0xF0) delta |= vp56_rac_get_prob(c, model->vector_fdv[comp][3])<<3; else delta |= 8; } else { delta = vp56_rac_get_tree(c, vp56_pva_tree, model->vector_pdv[comp]); } if (delta && vp56_rac_get_prob(c, model->vector_sig[comp])) delta = -delta; if (!comp) vect->x += delta; else vect->y += delta; } } /** * Read number of consecutive blocks with null DC or AC. * This value is < 74. */ static unsigned vp6_get_nb_null(VP56Context *s) { unsigned val = get_bits(&s->gb, 2); if (val == 2) val += get_bits(&s->gb, 2); else if (val == 3) { val = get_bits1(&s->gb) << 2; val = 6+val + get_bits(&s->gb, 2+val); } return val; } static void vp6_parse_coeff_huffman(VP56Context *s) { VP56Model *model = s->modelp; uint8_t *permute = s->scantable.permutated; VLC *vlc_coeff; int coeff, sign, coeff_idx; int b, cg, idx; int pt = 0; /* plane type (0 for Y, 1 for U or V) */ for (b=0; b<6; b++) { int ct = 0; /* code type */ if (b > 3) pt = 1; vlc_coeff = &s->dccv_vlc[pt]; for (coeff_idx=0; coeff_idx<64; ) { int run = 1; if (coeff_idx<2 && s->nb_null[coeff_idx][pt]) { s->nb_null[coeff_idx][pt]--; if (coeff_idx) break; } else { coeff = get_vlc2(&s->gb, vlc_coeff->table, 9, 3); if (coeff == 0) { if (coeff_idx) { int pt = (coeff_idx >= 6); run += get_vlc2(&s->gb, s->runv_vlc[pt].table, 9, 3); if (run >= 9) run += get_bits(&s->gb, 6); } else s->nb_null[0][pt] = vp6_get_nb_null(s); ct = 0; } else if (coeff == 11) { /* end of block */ if (coeff_idx == 1) /* first AC coeff ? */ s->nb_null[1][pt] = vp6_get_nb_null(s); break; } else { int coeff2 = vp56_coeff_bias[coeff]; if (coeff > 4) coeff2 += get_bits(&s->gb, coeff <= 9 ? coeff - 4 : 11); ct = 1 + (coeff2 > 1); sign = get_bits1(&s->gb); coeff2 = (coeff2 ^ -sign) + sign; if (coeff_idx) coeff2 *= s->dequant_ac; idx = model->coeff_index_to_pos[coeff_idx]; s->block_coeff[b][permute[idx]] = coeff2; } } coeff_idx+=run; cg = FFMIN(vp6_coeff_groups[coeff_idx], 3); vlc_coeff = &s->ract_vlc[pt][ct][cg]; } } } static void vp6_parse_coeff(VP56Context *s) { VP56RangeCoder *c = s->ccp; VP56Model *model = s->modelp; uint8_t *permute = s->scantable.permutated; uint8_t *model1, *model2, *model3; int coeff, sign, coeff_idx; int b, i, cg, idx, ctx; int pt = 0; /* plane type (0 for Y, 1 for U or V) */ for (b=0; b<6; b++) { int ct = 1; /* code type */ int run = 1; if (b > 3) pt = 1; ctx = s->left_block[vp56_b6to4[b]].not_null_dc + s->above_blocks[s->above_block_idx[b]].not_null_dc; model1 = model->coeff_dccv[pt]; model2 = model->coeff_dcct[pt][ctx]; for (coeff_idx=0; coeff_idx<64; ) { if ((coeff_idx>1 && ct==0) || vp56_rac_get_prob(c, model2[0])) { /* parse a coeff */ if (vp56_rac_get_prob(c, model2[2])) { if (vp56_rac_get_prob(c, model2[3])) { idx = vp56_rac_get_tree(c, vp56_pc_tree, model1); coeff = vp56_coeff_bias[idx+5]; for (i=vp56_coeff_bit_length[idx]; i>=0; i--) coeff += vp56_rac_get_prob(c, vp56_coeff_parse_table[idx][i]) << i; } else { if (vp56_rac_get_prob(c, model2[4])) coeff = 3 + vp56_rac_get_prob(c, model1[5]); else coeff = 2; } ct = 2; } else { ct = 1; coeff = 1; } sign = vp56_rac_get(c); coeff = (coeff ^ -sign) + sign; if (coeff_idx) coeff *= s->dequant_ac; idx = model->coeff_index_to_pos[coeff_idx]; s->block_coeff[b][permute[idx]] = coeff; run = 1; } else { /* parse a run */ ct = 0; if (coeff_idx > 0) { if (!vp56_rac_get_prob(c, model2[1])) break; model3 = model->coeff_runv[coeff_idx >= 6]; run = vp56_rac_get_tree(c, vp6_pcr_tree, model3); if (!run) for (run=9, i=0; i<6; i++) run += vp56_rac_get_prob(c, model3[i+8]) << i; } } cg = vp6_coeff_groups[coeff_idx+=run]; model1 = model2 = model->coeff_ract[pt][ct][cg]; } s->left_block[vp56_b6to4[b]].not_null_dc = s->above_blocks[s->above_block_idx[b]].not_null_dc = !!s->block_coeff[b][0]; } } static int vp6_adjust(int v, int t) { int V = v, s = v >> 31; V ^= s; V -= s; if (V-t-1 >= (unsigned)(t-1)) return v; V = 2*t - V; V += s; V ^= s; return V; } static int vp6_block_variance(uint8_t *src, int stride) { int sum = 0, square_sum = 0; int y, x; for (y=0; y<8; y+=2) { for (x=0; x<8; x+=2) { sum += src[x]; square_sum += src[x]*src[x]; } src += 2*stride; } return (16*square_sum - sum*sum) >> 8; } static void vp6_filter_hv4(uint8_t *dst, uint8_t *src, int stride, int delta, const int16_t *weights) { int x, y; for (y=0; y<8; y++) { for (x=0; x<8; x++) { dst[x] = av_clip_uint8(( src[x-delta ] * weights[0] + src[x ] * weights[1] + src[x+delta ] * weights[2] + src[x+2*delta] * weights[3] + 64) >> 7); } src += stride; dst += stride; } } static void vp6_filter_diag2(VP56Context *s, uint8_t *dst, uint8_t *src, int stride, int h_weight, int v_weight) { uint8_t *tmp = s->edge_emu_buffer+16; s->dsp.put_h264_chroma_pixels_tab[0](tmp, src, stride, 9, h_weight, 0); s->dsp.put_h264_chroma_pixels_tab[0](dst, tmp, stride, 8, 0, v_weight); } static void vp6_filter(VP56Context *s, uint8_t *dst, uint8_t *src, int offset1, int offset2, int stride, VP56mv mv, int mask, int select, int luma) { int filter4 = 0; int x8 = mv.x & mask; int y8 = mv.y & mask; if (luma) { x8 *= 2; y8 *= 2; filter4 = s->filter_mode; if (filter4 == 2) { if (s->max_vector_length && (FFABS(mv.x) > s->max_vector_length || FFABS(mv.y) > s->max_vector_length)) { filter4 = 0; } else if (s->sample_variance_threshold && (vp6_block_variance(src+offset1, stride) < s->sample_variance_threshold)) { filter4 = 0; } } } if ((y8 && (offset2-offset1)*s->flip<0) || (!y8 && offset1 > offset2)) { offset1 = offset2; } if (filter4) { if (!y8) { /* left or right combine */ vp6_filter_hv4(dst, src+offset1, stride, 1, vp6_block_copy_filter[select][x8]); } else if (!x8) { /* above or below combine */ vp6_filter_hv4(dst, src+offset1, stride, stride, vp6_block_copy_filter[select][y8]); } else { s->dsp.vp6_filter_diag4(dst, src+offset1+((mv.x^mv.y)>>31), stride, vp6_block_copy_filter[select][x8], vp6_block_copy_filter[select][y8]); } } else { if (!x8 || !y8) { s->dsp.put_h264_chroma_pixels_tab[0](dst, src+offset1, stride, 8, x8, y8); } else { vp6_filter_diag2(s, dst, src+offset1 + ((mv.x^mv.y)>>31), stride, x8, y8); } } } static av_cold int vp6_decode_init(AVCodecContext *avctx) { VP56Context *s = avctx->priv_data; vp56_init(avctx, avctx->codec->id == CODEC_ID_VP6, avctx->codec->id == CODEC_ID_VP6A); s->vp56_coord_div = vp6_coord_div; s->parse_vector_adjustment = vp6_parse_vector_adjustment; s->adjust = vp6_adjust; s->filter = vp6_filter; s->default_models_init = vp6_default_models_init; s->parse_vector_models = vp6_parse_vector_models; s->parse_coeff_models = vp6_parse_coeff_models; s->parse_header = vp6_parse_header; return 0; } AVCodec vp6_decoder = { "vp6", CODEC_TYPE_VIDEO, CODEC_ID_VP6, sizeof(VP56Context), vp6_decode_init, NULL, vp56_free, vp56_decode_frame, CODEC_CAP_DR1, .long_name = NULL_IF_CONFIG_SMALL("On2 VP6"), }; /* flash version, not flipped upside-down */ AVCodec vp6f_decoder = { "vp6f", CODEC_TYPE_VIDEO, CODEC_ID_VP6F, sizeof(VP56Context), vp6_decode_init, NULL, vp56_free, vp56_decode_frame, CODEC_CAP_DR1, .long_name = NULL_IF_CONFIG_SMALL("On2 VP6 (Flash version)"), }; /* flash version, not flipped upside-down, with alpha channel */ AVCodec vp6a_decoder = { "vp6a", CODEC_TYPE_VIDEO, CODEC_ID_VP6A, sizeof(VP56Context), vp6_decode_init, NULL, vp56_free, vp56_decode_frame, CODEC_CAP_DR1, .long_name = NULL_IF_CONFIG_SMALL("On2 VP6 (Flash version, with alpha channel)"), };