ref: de5fb20b98c830cf38e08058c4df874c9ab6f816
dir: /jpc_tagtree.c/
/* * Copyright (c) 1999-2000 Image Power, Inc. and the University of * British Columbia. * Copyright (c) 2001-2003 Michael David Adams. * All rights reserved. */ /* __START_OF_JASPER_LICENSE__ * * JasPer License Version 2.0 * * Copyright (c) 2001-2006 Michael David Adams * Copyright (c) 1999-2000 Image Power, Inc. * Copyright (c) 1999-2000 The University of British Columbia * * All rights reserved. * * Permission is hereby granted, free of charge, to any person (the * "User") obtaining a copy of this software and associated documentation * files (the "Software"), to deal in the Software without restriction, * including without limitation the rights to use, copy, modify, merge, * publish, distribute, and/or sell copies of the Software, and to permit * persons to whom the Software is furnished to do so, subject to the * following conditions: * * 1. The above copyright notices and this permission notice (which * includes the disclaimer below) shall be included in all copies or * substantial portions of the Software. * * 2. The name of a copyright holder shall not be used to endorse or * promote products derived from the Software without specific prior * written permission. * * THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL PART OF THIS * LICENSE. NO USE OF THE SOFTWARE IS AUTHORIZED HEREUNDER EXCEPT UNDER * THIS DISCLAIMER. THE SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS * "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS. IN NO * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL * INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. NO ASSURANCES ARE * PROVIDED BY THE COPYRIGHT HOLDERS THAT THE SOFTWARE DOES NOT INFRINGE * THE PATENT OR OTHER INTELLECTUAL PROPERTY RIGHTS OF ANY OTHER ENTITY. * EACH COPYRIGHT HOLDER DISCLAIMS ANY LIABILITY TO THE USER FOR CLAIMS * BROUGHT BY ANY OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL * PROPERTY RIGHTS OR OTHERWISE. AS A CONDITION TO EXERCISING THE RIGHTS * GRANTED HEREUNDER, EACH USER HEREBY ASSUMES SOLE RESPONSIBILITY TO SECURE * ANY OTHER INTELLECTUAL PROPERTY RIGHTS NEEDED, IF ANY. THE SOFTWARE * IS NOT FAULT-TOLERANT AND IS NOT INTENDED FOR USE IN MISSION-CRITICAL * SYSTEMS, SUCH AS THOSE USED IN THE OPERATION OF NUCLEAR FACILITIES, * AIRCRAFT NAVIGATION OR COMMUNICATION SYSTEMS, AIR TRAFFIC CONTROL * SYSTEMS, DIRECT LIFE SUPPORT MACHINES, OR WEAPONS SYSTEMS, IN WHICH * THE FAILURE OF THE SOFTWARE OR SYSTEM COULD LEAD DIRECTLY TO DEATH, * PERSONAL INJURY, OR SEVERE PHYSICAL OR ENVIRONMENTAL DAMAGE ("HIGH * RISK ACTIVITIES"). THE COPYRIGHT HOLDERS SPECIFICALLY DISCLAIM ANY * EXPRESS OR IMPLIED WARRANTY OF FITNESS FOR HIGH RISK ACTIVITIES. * * __END_OF_JASPER_LICENSE__ */ /* * Tag Tree Library * * $Id$ */ /******************************************************************************\ * Includes. \******************************************************************************/ #include "jpc_tagtree.h" #include "jasper/jas_malloc.h" #include "jasper/jas_stream.h" /******************************************************************************\ * Prototypes. \******************************************************************************/ static jpc_tagtree_t *jpc_tagtree_alloc(void); /******************************************************************************\ * Code for creating and destroying tag trees. \******************************************************************************/ /* Create a tag tree. */ jpc_tagtree_t *jpc_tagtree_create(int numleafsh, int numleafsv) { int nplh[JPC_TAGTREE_MAXDEPTH]; int nplv[JPC_TAGTREE_MAXDEPTH]; jpc_tagtreenode_t *node; jpc_tagtreenode_t *parentnode; jpc_tagtreenode_t *parentnode0; jpc_tagtree_t *tree; int i; int j; int k; int numlvls; int n; assert(numleafsh > 0 && numleafsv > 0); if (!(tree = jpc_tagtree_alloc())) { return 0; } tree->numleafsh_ = numleafsh; tree->numleafsv_ = numleafsv; numlvls = 0; nplh[0] = numleafsh; nplv[0] = numleafsv; do { n = nplh[numlvls] * nplv[numlvls]; nplh[numlvls + 1] = (nplh[numlvls] + 1) / 2; nplv[numlvls + 1] = (nplv[numlvls] + 1) / 2; tree->numnodes_ += n; ++numlvls; } while (n > 1); if (!(tree->nodes_ = jas_alloc2(tree->numnodes_, sizeof(jpc_tagtreenode_t)))) { jpc_tagtree_destroy(tree); return 0; } /* Initialize the parent links for all nodes in the tree. */ node = tree->nodes_; parentnode = &tree->nodes_[tree->numleafsh_ * tree->numleafsv_]; parentnode0 = parentnode; for (i = 0; i < numlvls - 1; ++i) { for (j = 0; j < nplv[i]; ++j) { k = nplh[i]; while (--k >= 0) { node->parent_ = parentnode; ++node; if (--k >= 0) { node->parent_ = parentnode; ++node; } ++parentnode; } if ((j & 1) || j == nplv[i] - 1) { parentnode0 = parentnode; } else { parentnode = parentnode0; parentnode0 += nplh[i]; } } } node->parent_ = 0; /* Initialize the data values to something sane. */ jpc_tagtree_reset(tree); return tree; } /* Destroy a tag tree. */ void jpc_tagtree_destroy(jpc_tagtree_t *tree) { jas_free(tree->nodes_); jas_free(tree); } static jpc_tagtree_t *jpc_tagtree_alloc() { jpc_tagtree_t *tree; if (!(tree = jas_malloc(sizeof(jpc_tagtree_t)))) { return 0; } tree->numleafsh_ = 0; tree->numleafsv_ = 0; tree->numnodes_ = 0; tree->nodes_ = 0; return tree; } /******************************************************************************\ * Code. \******************************************************************************/ /* Copy state information from one tag tree to another. */ void jpc_tagtree_copy(jpc_tagtree_t *dsttree, const jpc_tagtree_t *srctree) { int n; jpc_tagtreenode_t *dstnode; /* The two tag trees must have similar sizes. */ assert(srctree->numleafsh_ == dsttree->numleafsh_ && srctree->numleafsv_ == dsttree->numleafsv_); n = srctree->numnodes_; const jpc_tagtreenode_t *srcnode = srctree->nodes_; dstnode = dsttree->nodes_; while (--n >= 0) { dstnode->value_ = srcnode->value_; dstnode->low_ = srcnode->low_; dstnode->known_ = srcnode->known_; ++dstnode; ++srcnode; } } /* Reset all of the state information associated with a tag tree. */ void jpc_tagtree_reset(jpc_tagtree_t *tree) { int n; jpc_tagtreenode_t *node; n = tree->numnodes_; node = tree->nodes_; while (--n >= 0) { node->value_ = INT_MAX; node->low_ = 0; node->known_ = 0; ++node; } } /* Set the value associated with the specified leaf node, updating the other nodes as necessary. */ void jpc_tagtree_setvalue(jpc_tagtree_t *tree, jpc_tagtreenode_t *leaf, int value) { jpc_tagtreenode_t *node; /* Avoid compiler warnings about unused parameters. */ USED(tree); assert(value >= 0); node = leaf; while (node && node->value_ > value) { node->value_ = value; node = node->parent_; } } /* Get a particular leaf node. */ jpc_tagtreenode_t *jpc_tagtree_getleaf(jpc_tagtree_t *tree, int n) { return &tree->nodes_[n]; } /* Invoke the tag tree encoding procedure. */ int jpc_tagtree_encode(jpc_tagtree_t *tree, jpc_tagtreenode_t *leaf, int threshold, jpc_bitstream_t *out) { jpc_tagtreenode_t *stk[JPC_TAGTREE_MAXDEPTH - 1]; jpc_tagtreenode_t **stkptr; jpc_tagtreenode_t *node; int low; /* Avoid compiler warnings about unused parameters. */ USED(tree); assert(leaf); assert(threshold >= 0); /* Traverse to the root of the tree, recording the path taken. */ stkptr = stk; node = leaf; while (node->parent_) { *stkptr++ = node; node = node->parent_; } low = 0; for (;;) { if (low > node->low_) { /* Deferred propagation of the lower bound downward in the tree. */ node->low_ = low; } else { low = node->low_; } while (low < threshold) { if (low >= node->value_) { if (!node->known_) { if (jpc_bitstream_putbit(out, 1) == EOF) { return -1; } node->known_ = 1; } break; } if (jpc_bitstream_putbit(out, 0) == EOF) { return -1; } ++low; } node->low_ = low; if (stkptr == stk) { break; } node = *--stkptr; } return (leaf->low_ < threshold) ? 1 : 0; } /* Invoke the tag tree decoding procedure. */ int jpc_tagtree_decode(jpc_tagtree_t *tree, jpc_tagtreenode_t *leaf, int threshold, jpc_bitstream_t *in) { jpc_tagtreenode_t *stk[JPC_TAGTREE_MAXDEPTH - 1]; jpc_tagtreenode_t **stkptr; jpc_tagtreenode_t *node; int low; int ret; /* Avoid compiler warnings about unused parameters. */ USED(tree); assert(threshold >= 0); /* Traverse to the root of the tree, recording the path taken. */ stkptr = stk; node = leaf; while (node->parent_) { *stkptr++ = node; node = node->parent_; } low = 0; for (;;) { if (low > node->low_) { node->low_ = low; } else { low = node->low_; } while (low < threshold && low < node->value_) { if ((ret = jpc_bitstream_getbit(in)) < 0) { return -1; } if (ret) { node->value_ = low; } else { ++low; } } node->low_ = low; if (stkptr == stk) { break; } node = *--stkptr; } return (node->value_ < threshold) ? 1 : 0; }