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Checked key_size in LSH table for validness (#2677)

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This commit is contained in:
Ilya Lysenkov 2013-01-31 23:19:19 +04:00
parent 1becbd9fcc
commit 098ea6fcb7
1 changed files with 14 additions and 4 deletions
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18
modules/flann/include/opencv2/flann/lsh_table.h
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@ -261,6 +261,16 @@ private:
*/ */
void initialize(size_t key_size) void initialize(size_t key_size)
{ {
const size_t key_size_lower_bound = 1;
//a value (size_t(1) << key_size) must fit the size_t type so key_size has to be strictly less than size of size_t
const size_t key_size_upper_bound = std::min(sizeof(BucketKey) * CHAR_BIT + 1, sizeof(size_t) * CHAR_BIT);
if (key_size < key_size_lower_bound || key_size >= key_size_upper_bound)
{
std::stringstream errorMessage;
errorMessage << "Invalid key_size (=" << key_size << "). Valid values for your system are " << key_size_lower_bound << " <= key_size < " << key_size_upper_bound << ".";
CV_Error(CV_StsBadArg, errorMessage.str());
}
speed_level_ = kHash; speed_level_ = kHash;
key_size_ = (unsigned)key_size; key_size_ = (unsigned)key_size;
} }
@ -273,10 +283,10 @@ private:
if (speed_level_ == kArray) return; if (speed_level_ == kArray) return;
// Use an array if it will be more than half full // Use an array if it will be more than half full
if (buckets_space_.size() > (unsigned int)((1 << key_size_) / 2)) { if (buckets_space_.size() > ((size_t(1) << key_size_) / 2)) {
speed_level_ = kArray; speed_level_ = kArray;
// Fill the array version of it // Fill the array version of it
buckets_speed_.resize(1 << key_size_); buckets_speed_.resize(size_t(1) << key_size_);
for (BucketsSpace::const_iterator key_bucket = buckets_space_.begin(); key_bucket != buckets_space_.end(); ++key_bucket) buckets_speed_[key_bucket->first] = key_bucket->second; for (BucketsSpace::const_iterator key_bucket = buckets_space_.begin(); key_bucket != buckets_space_.end(); ++key_bucket) buckets_speed_[key_bucket->first] = key_bucket->second;
// Empty the hash table // Empty the hash table
@ -287,9 +297,9 @@ private:
// If the bitset is going to use less than 10% of the RAM of the hash map (at least 1 size_t for the key and two // If the bitset is going to use less than 10% of the RAM of the hash map (at least 1 size_t for the key and two
// for the vector) or less than 512MB (key_size_ <= 30) // for the vector) or less than 512MB (key_size_ <= 30)
if (((std::max(buckets_space_.size(), buckets_speed_.size()) * CHAR_BIT * 3 * sizeof(BucketKey)) / 10 if (((std::max(buckets_space_.size(), buckets_speed_.size()) * CHAR_BIT * 3 * sizeof(BucketKey)) / 10
>= size_t(1 << key_size_)) || (key_size_ <= 32)) { >= (size_t(1) << key_size_)) || (key_size_ <= 32)) {
speed_level_ = kBitsetHash; speed_level_ = kBitsetHash;
key_bitset_.resize(1 << key_size_); key_bitset_.resize(size_t(1) << key_size_);
key_bitset_.reset(); key_bitset_.reset();
// Try with the BucketsSpace // Try with the BucketsSpace
for (BucketsSpace::const_iterator key_bucket = buckets_space_.begin(); key_bucket != buckets_space_.end(); ++key_bucket) key_bitset_.set(key_bucket->first); for (BucketsSpace::const_iterator key_bucket = buckets_space_.begin(); key_bucket != buckets_space_.end(); ++key_bucket) key_bitset_.set(key_bucket->first);