From 437c2079b7984f4989dbc924cf06d1645fa90d82 Mon Sep 17 00:00:00 2001 From: Aurelien Jacobs Date: Sun, 14 Oct 2007 21:19:40 +0000 Subject: [PATCH] moves fraps huffman decoder to its own file, making it more generic Originally committed as revision 10736 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavcodec/Makefile | 2 +- libavcodec/fraps.c | 88 ++++-------------------------------- libavcodec/huffman.c | 103 +++++++++++++++++++++++++++++++++++++++++++ libavcodec/huffman.h | 38 ++++++++++++++++ 4 files changed, 150 insertions(+), 81 deletions(-) create mode 100644 libavcodec/huffman.c create mode 100644 libavcodec/huffman.h diff --git a/libavcodec/Makefile b/libavcodec/Makefile index e79038e2a7..58ce31ec09 100644 --- a/libavcodec/Makefile +++ b/libavcodec/Makefile @@ -79,7 +79,7 @@ OBJS-$(CONFIG_FLIC_DECODER) += flicvideo.o OBJS-$(CONFIG_FLV_DECODER) += h263dec.o h263.o OBJS-$(CONFIG_FLV_ENCODER) += mpegvideo_enc.o motion_est.o ratecontrol.o h263.o OBJS-$(CONFIG_FOURXM_DECODER) += 4xm.o -OBJS-$(CONFIG_FRAPS_DECODER) += fraps.o +OBJS-$(CONFIG_FRAPS_DECODER) += fraps.o huffman.o OBJS-$(CONFIG_GIF_DECODER) += gifdec.o lzw.o OBJS-$(CONFIG_GIF_ENCODER) += gif.o OBJS-$(CONFIG_H261_DECODER) += h261dec.o h261.o diff --git a/libavcodec/fraps.c b/libavcodec/fraps.c index a15f602a57..73465de9af 100644 --- a/libavcodec/fraps.c +++ b/libavcodec/fraps.c @@ -33,30 +33,18 @@ #include "avcodec.h" #include "bitstream.h" +#include "huffman.h" +#include "bytestream.h" #include "dsputil.h" #define FPS_TAG MKTAG('F', 'P', 'S', 'x') -/* symbol for Huffman tree node */ -#define HNODE -1 - -/** - * Huffman node - * FIXME one day this should belong to one general framework - */ -typedef struct Node{ - int16_t sym; - int16_t n0; - int count; -}Node; - /** * local variable storage */ typedef struct FrapsContext{ AVCodecContext *avctx; AVFrame frame; - Node nodes[512]; uint8_t *tmpbuf; DSPContext dsp; } FrapsContext; @@ -92,36 +80,6 @@ static int huff_cmp(const void *va, const void *vb){ return (a->count - b->count)*256 + a->sym - b->sym; } -static void get_tree_codes(uint32_t *bits, int16_t *lens, uint8_t *xlat, Node *nodes, int node, uint32_t pfx, int pl, int *pos) -{ - int s; - - s = nodes[node].sym; - if(s != HNODE || !nodes[node].count){ - bits[*pos] = pfx; - lens[*pos] = pl; - xlat[*pos] = s; - (*pos)++; - }else{ - pfx <<= 1; - pl++; - get_tree_codes(bits, lens, xlat, nodes, nodes[node].n0, pfx, pl, pos); - pfx |= 1; - get_tree_codes(bits, lens, xlat, nodes, nodes[node].n0+1, pfx, pl, pos); - } -} - -static int build_huff_tree(VLC *vlc, Node *nodes, uint8_t *xlat) -{ - uint32_t bits[256]; - int16_t lens[256]; - int pos = 0; - - get_tree_codes(bits, lens, xlat, nodes, 510, 0, 0, &pos); - return init_vlc(vlc, 9, pos, lens, 2, 2, bits, 4, 4, 0); -} - - /** * decode Fraps v2 packed plane */ @@ -129,45 +87,15 @@ static int fraps2_decode_plane(FrapsContext *s, uint8_t *dst, int stride, int w, int h, uint8_t *src, int size, int Uoff) { int i, j; - int cur_node; GetBitContext gb; VLC vlc; - int64_t sum = 0; - uint8_t recode[256]; - - for(i = 0; i < 256; i++){ - s->nodes[i].sym = i; - s->nodes[i].count = AV_RL32(src); - s->nodes[i].n0 = -2; - if(s->nodes[i].count < 0) { - av_log(s->avctx, AV_LOG_ERROR, "Symbol count < 0\n"); - return -1; - } - src += 4; - sum += s->nodes[i].count; - } - size -= 1024; + Node nodes[512]; - if(sum >> 31) { - av_log(s->avctx, AV_LOG_ERROR, "Too high symbol frequencies. Tree construction is not possible\n"); - return -1; - } - qsort(s->nodes, 256, sizeof(Node), huff_cmp); - cur_node = 256; - for(i = 0; i < 511; i += 2){ - s->nodes[cur_node].sym = HNODE; - s->nodes[cur_node].count = s->nodes[i].count + s->nodes[i+1].count; - s->nodes[cur_node].n0 = i; - for(j = cur_node; j > 0; j--){ - if(s->nodes[j].count >= s->nodes[j - 1].count) break; - FFSWAP(Node, s->nodes[j], s->nodes[j - 1]); - } - cur_node++; - } - if(build_huff_tree(&vlc, s->nodes, recode) < 0){ - av_log(s->avctx, AV_LOG_ERROR, "Error building tree\n"); + for(i = 0; i < 256; i++) + nodes[i].count = bytestream_get_le32(&src); + size -= 1024; + if (ff_huff_build_tree(s->avctx, &vlc, 256, nodes, huff_cmp, 0) < 0) return -1; - } /* we have built Huffman table and are ready to decode plane */ /* convert bits so they may be used by standard bitreader */ @@ -176,7 +104,7 @@ static int fraps2_decode_plane(FrapsContext *s, uint8_t *dst, int stride, int w, init_get_bits(&gb, s->tmpbuf, size * 8); for(j = 0; j < h; j++){ for(i = 0; i < w; i++){ - dst[i] = recode[get_vlc2(&gb, vlc.table, 9, 3)]; + dst[i] = get_vlc2(&gb, vlc.table, 9, 3); /* lines are stored as deltas between previous lines * and we need to add 0x80 to the first lines of chroma planes */ diff --git a/libavcodec/huffman.c b/libavcodec/huffman.c new file mode 100644 index 0000000000..298dc15397 --- /dev/null +++ b/libavcodec/huffman.c @@ -0,0 +1,103 @@ +/** + * @file huffman.c + * huffman tree builder and VLC generator + * Copyright (c) 2006 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 + */ + +#include "avcodec.h" +#include "bitstream.h" +#include "huffman.h" + +/* symbol for Huffman tree node */ +#define HNODE -1 + + +static void get_tree_codes(uint32_t *bits, int16_t *lens, uint8_t *xlat, Node *nodes, int node, uint32_t pfx, int pl, int *pos) +{ + int s; + + s = nodes[node].sym; + if(s != HNODE || !nodes[node].count){ + bits[*pos] = pfx; + lens[*pos] = pl; + xlat[*pos] = s; + (*pos)++; + }else{ + pfx <<= 1; + pl++; + get_tree_codes(bits, lens, xlat, nodes, nodes[node].n0, pfx, pl, pos); + pfx |= 1; + get_tree_codes(bits, lens, xlat, nodes, nodes[node].n0+1, pfx, pl, pos); + } +} + +static int build_huff_tree(VLC *vlc, Node *nodes, int head) +{ + uint32_t bits[256]; + int16_t lens[256]; + uint8_t xlat[256]; + int pos = 0; + + get_tree_codes(bits, lens, xlat, nodes, head, 0, 0, &pos); + return init_vlc_sparse(vlc, 9, pos, lens, 2, 2, bits, 4, 4, xlat, 1, 1, 0); +} + + +/** + * first nb_codes nodes.count must be set + */ +int ff_huff_build_tree(AVCodecContext *avctx, VLC *vlc, int nb_codes, + Node nodes[2*nb_codes], huff_cmp_t cmp, int hnode_first) +{ + int i, j; + int cur_node; + int64_t sum = 0; + + for(i = 0; i < nb_codes; i++){ + nodes[i].sym = i; + nodes[i].n0 = -2; + sum += nodes[i].count; + } + + if(sum >> 31) { + av_log(avctx, AV_LOG_ERROR, "Too high symbol frequencies. Tree construction is not possible\n"); + return -1; + } + qsort(nodes, nb_codes, sizeof(Node), cmp); + cur_node = nb_codes; + for(i = 0; i < nb_codes*2-1; i += 2){ + nodes[cur_node].sym = HNODE; + nodes[cur_node].count = nodes[i].count + nodes[i+1].count; + nodes[cur_node].n0 = i; + for(j = cur_node; j > 0; j--){ + if(nodes[j].count > nodes[j-1].count || + (nodes[j].count == nodes[j-1].count && + (!hnode_first || nodes[j].n0==j-1 || nodes[j].n0==j-2 || + (nodes[j].sym!=HNODE && nodes[j-1].sym!=HNODE)))) + break; + FFSWAP(Node, nodes[j], nodes[j-1]); + } + cur_node++; + } + if(build_huff_tree(vlc, nodes, nb_codes*2-2) < 0){ + av_log(avctx, AV_LOG_ERROR, "Error building tree\n"); + return -1; + } + return 0; +} diff --git a/libavcodec/huffman.h b/libavcodec/huffman.h new file mode 100644 index 0000000000..0474fbafb4 --- /dev/null +++ b/libavcodec/huffman.h @@ -0,0 +1,38 @@ +/** + * @file huffman.h + * huffman tree builder and VLC generator + * Copyright (C) 2007 Aurelien Jacobs + * + * 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 + */ + +#ifndef AVCODEC_HUFFMAN_H +#define AVCODEC_HUFFMAN_H + +#include "avcodec.h" + +typedef struct { + int16_t sym; + int16_t n0; + uint32_t count; +} Node; + +typedef int (*huff_cmp_t)(const void *va, const void *vb); +int ff_huff_build_tree(AVCodecContext *avctx, VLC *vlc, int nb_codes, + Node nodes[2*nb_codes], huff_cmp_t cmp, int hnode_first); + +#endif /* AVCODEC_HUFFMAN_H */