2019-06-06 15:21:15 +03:00

113 lines
4.3 KiB
Java

/*******************************************************************************
* Copyright (c) 2015-2018 Skymind, Inc.
*
* This program and the accompanying materials are made available under the
* terms of the Apache License, Version 2.0 which is available at
* https://www.apache.org/licenses/LICENSE-2.0.
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
* SPDX-License-Identifier: Apache-2.0
******************************************************************************/
package org.deeplearning4j.zoo;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.io.FileUtils;
import org.deeplearning4j.common.resources.DL4JResources;
import org.deeplearning4j.common.resources.ResourceType;
import org.deeplearning4j.nn.api.Model;
import org.deeplearning4j.nn.graph.ComputationGraph;
import org.deeplearning4j.nn.multilayer.MultiLayerNetwork;
import org.deeplearning4j.util.ModelSerializer;
import java.io.File;
import java.io.IOException;
import java.net.URL;
import java.util.zip.Adler32;
import java.util.zip.Checksum;
/**
* A zoo model is instantiable, returns information about itself, and can download
* pretrained models if available.
*
* @author Justin Long (crockpotveggies)
*/
@Slf4j
public abstract class ZooModel<T> implements InstantiableModel {
public boolean pretrainedAvailable(PretrainedType pretrainedType) {
return pretrainedUrl(pretrainedType) != null;
}
/**
* By default, will return a pretrained ImageNet if available.
*
* @return
* @throws IOException
*/
public Model initPretrained() throws IOException {
return initPretrained(PretrainedType.IMAGENET);
}
/**
* Returns a pretrained model for the given dataset, if available.
*
* @param pretrainedType
* @return
* @throws IOException
*/
public <M extends Model> M initPretrained(PretrainedType pretrainedType) throws IOException {
String remoteUrl = pretrainedUrl(pretrainedType);
if (remoteUrl == null)
throw new UnsupportedOperationException(
"Pretrained " + pretrainedType + " weights are not available for this model.");
String localFilename = new File(remoteUrl).getName();
File rootCacheDir = DL4JResources.getDirectory(ResourceType.ZOO_MODEL, modelName());
File cachedFile = new File(rootCacheDir, localFilename);
if (!cachedFile.exists()) {
log.info("Downloading model to " + cachedFile.toString());
FileUtils.copyURLToFile(new URL(remoteUrl), cachedFile);
} else {
log.info("Using cached model at " + cachedFile.toString());
}
long expectedChecksum = pretrainedChecksum(pretrainedType);
if (expectedChecksum != 0L) {
log.info("Verifying download...");
Checksum adler = new Adler32();
FileUtils.checksum(cachedFile, adler);
long localChecksum = adler.getValue();
log.info("Checksum local is " + localChecksum + ", expecting " + expectedChecksum);
if (expectedChecksum != localChecksum) {
log.error("Checksums do not match. Cleaning up files and failing...");
cachedFile.delete();
throw new IllegalStateException(
"Pretrained model file failed checksum. If this error persists, please open an issue at https://github.com/deeplearning4j/deeplearning4j.");
}
}
if (modelType() == MultiLayerNetwork.class) {
return (M) ModelSerializer.restoreMultiLayerNetwork(cachedFile);
} else if (modelType() == ComputationGraph.class) {
return (M) ModelSerializer.restoreComputationGraph(cachedFile);
} else {
throw new UnsupportedOperationException(
"Pretrained models are only supported for MultiLayerNetwork and ComputationGraph.");
}
}
@Override
public String modelName() {
return getClass().getSimpleName().toLowerCase();
}
}