ImageChangeFormatOp.java

/*
 * (C) Copyright 2016 Nuxeo SA (http://nuxeo.com/) and others.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://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.
 *
 * Contributors:
 *     Thibaud Arguillere
 */
package org.nuxeo.labs.images;

import java.io.Serializable;
import java.util.HashMap;
import java.util.Map;

import org.nuxeo.ecm.automation.core.Constants;
import org.nuxeo.ecm.automation.core.annotations.Operation;
import org.nuxeo.ecm.automation.core.annotations.OperationMethod;
import org.nuxeo.ecm.automation.core.annotations.Param;
import org.nuxeo.ecm.automation.core.collectors.BlobCollector;
import org.nuxeo.ecm.core.api.Blob;

/**
 * With ImageMagick, changing the format of a picture is about changing the
 * extension of the file. For example: convert something.jpg somethingelse.png
 * 
 * See comments in GenericImageMagickConverter for (a bit) more explanations
 * about converters and commandLines.
 * 
 * @since 5.9.6
 */
@Operation(id = ImageChangeFormatOp.ID, category = Constants.CAT_CONVERSION, label = "Image: Change Format", description = "Convert the image to another format (The operation uses ImageMagick, valid format are png, jpg, jpeg, git, tiff, ...)<p>If <code>targetFileName</code> is not provided, the output blob filename will be the same as the picture to convert (with a new extension). Also, if <code>targetFileSuffix</code> is used, it will be added to the target file name <i>before</i> the extension (So, if the file name is 'mypict.jpg', the suffix is '-copy', and the format is 'png', the target file name will be 'mypict-copy.png')</p>")
public class ImageChangeFormatOp {

    public static final String ID = "ImageChangeFormat";

    @Param(name = "format", required = true)
    protected String format;

    @Param(name = "targetFileName", required = false)
    protected String targetFileName;

    @Param(name = "targetFileNameSuffix", required = false)
    protected String targetFileNameSuffix = "";

    @OperationMethod(collector = BlobCollector.class)
    public Blob run(Blob inBlob) {

        targetFileName = ConversionUtils.updateTargetFileName(inBlob,
                targetFileName, targetFileNameSuffix);
        // Remove the extension before calling ImageMagick commandLine (which
        // adds #{format})
        int dotIndex = targetFileName.lastIndexOf('.');
        if (dotIndex > 0) {
            targetFileName = targetFileName.substring(0, dotIndex);
        }

        Map<String, Serializable> params = new HashMap<String, Serializable>();
        params.put("targetFilePath", targetFileName);
        params.put("format", format);

        // The "changeFormat" converter is defined in
        // OSGI-INF/extensions/conversions-contrib.xml
        Blob result = ConversionUtils.convert("changeFormat", inBlob, params,
                targetFileName + "." + format);
        return result;
    }
}