shared_ptr<Patch> CachingPyramidFeatureExtractor::extractOutputCopying(CacheLayer& layer, int x, int y) const {
CacheKey key(x, y);
unordered_map<CacheKey, shared_ptr<Patch>, CacheKey::hash>& layerCache = layer.getCache();
auto iterator = layerCache.find(key);
if (iterator == layerCache.end()) {
shared_ptr<Patch> patch = extractor->extract(layer.getIndex(), x, y);
layerCache.emplace(key, patch);
return patch;
}
return make_shared<Patch>(*(iterator->second));
}
shared_ptr<Patch> CachingPyramidFeatureExtractor::extractInputCopying(CacheLayer& layer, int x, int y) const {
CacheKey key(x, y);
unordered_map<CacheKey, shared_ptr<Patch>, CacheKey::hash>& layerCache = layer.getCache();
auto iterator = layerCache.find(key);
if (iterator == layerCache.end()) {
shared_ptr<Patch> patch = extractor->extract(layer.getIndex(), x, y);
if (patch) // store a copy of the patch only if it exists
layerCache.emplace(key, make_shared<Patch>(*patch));
return patch;
}
return iterator->second;
}
