/*
* Copyright (C) 2005-2010 Alfresco Software Limited.
*
* This file is part of Alfresco
*
* Alfresco is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* Alfresco is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with Alfresco. If not, see
* If no value is specified for this parameter then the width of the image
* will be unchanged.
* If an image is being cropped and resized then the cropping happens first,
* followed by resizing of the cropped image.
*/
public static final String PARAM_RESIZE_WIDTH = "xsize";
/**
* This optional {@link Integer} or {@link Float} parameter specifies the
* height of the image after resizing. This may be expressed as pixels or it
* may represent a percentage of the original image width, depending on the
* value of the PARAM_IS_PERCENT_RESIZE parameter.
* If no value is specified for this parameter then the height of the image
* will be unchanged.
* If an image is being cropped and resized then the cropping happens
* first, followed by resizing of the cropped image.
*/
public static final String PARAM_RESIZE_HEIGHT = "ysize";
/**
* This optional {@link Boolean} flag parameter specifies how the
* PARAM_RESIZE_HEIGHT and PARAM_RESIZE_WIDTH parameters are interpreted. If
* this parameter is set to true
then the rendition height and
* width are represented as a percentage of the original image height and
* width. If this parameter is set to false
then the rendition
* height and width are represented as pixels. This parameter defaults to
* false
.
*/
public static final String PARAM_IS_PERCENT_RESIZE = "isAbsolute";
/**
* This optional {@link Boolean} flag parameter determines whether the
* rendered image maintains its original aspect ratio or is stretched to fit
* the specified height and width.
* If this parameter is true
then the rendered image will
* always maintain its aspect ratio and will be resized to best fit within
* the given width and height. For example if an image starts at 100x200
* pixels and it is resized to 50x50 pixels then the rendered image will
* actually be 25x50 pixels.
* If this parameter is false
then the image will be stretched
* or compressed to fit the given height and width, regardless of the
* original aspect ratio.
* This parameter defaults to true
*/
public static final String PARAM_MAINTAIN_ASPECT_RATIO = "maintainAspectRatio";
/**
* This optional {@link Boolean} flag parameter specifies a mode for
* dramatically shrinking large images in a performant way.
* If set to true
the rendering process will be more performant
* for large images but the rendered image will be of lower quality.
* If set to false
the rendering process will take longer but
* the resulting image will usually be of better quality.
*/
public static final String PARAM_RESIZE_TO_THUMBNAIL = "resizeToThumbnail";
// Crop params
/**
* This optional {@link Integer} or {@link Float} parameter specifies the
* width of the image after cropping. This may be expressed as pixels or it
* may represent a percentage of the original image width, depending on the
* value of the PARAM_IS_PERCENT_CROP parameter.
* If no value is specified for this parameter then the width of the image
* will be unchanged.
* If an image is being cropped and resized then the cropping happens first,
* followed by resizing of the cropped image.
*/
public static final String PARAM_CROP_WIDTH = "crop_width";
/**
* This optional {@link Integer} or {@link Float} parameter specifies the
* height of the image after cropping. This may be expressed as pixels or it
* may represent a percentage of the original image width, depending on the
* value of the PARAM_IS_PERCENT_CROP parameter.
* If no value is specified for this parameter then the width of the image
* will be unchanged.
* If an image is being cropped and resized then the cropping happens first,
* followed by resizing of the cropped image.
*/
public static final String PARAM_CROP_HEIGHT = "crop_height";
/**
* This optional {@link Integer} parameter specifies the horizontal position
* of the start point of the area to be cropped. By default this parameter
* sets the distance, in pixels, from the left-hand edge of the image to the
* start position of the crop area. By default a positive value will shift
* the start-position to the right, while a negative value will shift the
* start position to the left. Setting the PARAM_CROP_GRAVITY parameter may
* change this, however.
* If this parameter is not set it is assumed to be 0.
*/
public static final String PARAM_CROP_X_OFFSET = "crop_x";
/**
* This optional {@link Integer} parameter specifies the vertical position
* of the start point of the area to be cropped. By default this parameter
* sets the distance, in pixels, from the top edge of the image to the start
* position of the crop area. By default a positive value will shift the
* start-position downwards, while a negative value will shift the start
* position upwards. Setting the PARAM_CROP_GRAVITY parameter may change
* this, however.
* If this parameter is not set it is assumed to be 0.
*/
public static final String PARAM_CROP_Y_OFFSET = "crop_y";
/**
* This optional {@link String} parameter determines the 'zero' position
* from which offsets are measured and also determines the direction of
* offsets. The allowed values of gravity are the four cardinal points
* (North, East, etc.), the four ordinal points (NorhtWest, SouthEast, etc)
* and Center. By default NorthWest gravity is used.
*
* * If an ordinal gravity is set then the point from which offsets originate * will be the appropriate corner. For example, NorthWest gravity would * originate at teh top-left corner while SouthWest origin would originate * at the bottom-left corner. Cardinal gravity sets the origin at the center * of the appropriate edge. Center origin sets the origin at the center of * the image. *
* * Gravity also affects the direction of offsets and how the offset position * relates to the cropped image. For example, NorthWest gravity sets * positive horizontal offset direction to right, positive vertical * direction to down and sets the cropped image origin to the top-left * corner. Northerly gavities set the positive vertical direction to down. * Southerly gavities set teh positive vertical direction to up. Easterly * gavities set teh positive horizontal positive direction to left. Westerly * gavities set teh positive horizontal positive direction to right. *
* Some gravity values do not specify a horizontal or a vertical direction * explicitly. For example North does not specify a horizontal direction, * while Center does not specify either horizontal or vertical direction. In * thse cases the positive horizontal offset direction is always right and * the positive vertical offset direction is always down. *
*
* The gravity also affects how the cropped image relates to the offset
* position. For example, NorthWest gravity causes the top-left corner of
* the cropped area to be the offset position, while NorthEast gravity would
* set the top-right corner of the cropped are to the offset position. When
* a direction is not explicitly specified then the center of the cropped
* area is placed at the offset position. For example, with North gravity
* the horizontal position is unspecified so the cropped area would be
* horizontally centered on the offset position, but the top edge of the
* cropped area would be at the offset position. For Center gravity the
* cropped area will be centered over the offset position both horizontally
* and vertically.
*/
public static final String PARAM_CROP_GRAVITY = "crop_gravity";
/**
* This optional {@link Boolean} flag parameter specifies how the
* PARAM_CROP_HEIGHT and PARAM_CROP_WIDTH parameters are interpreted. If
* this parameter is set to true
then the cropped image height and
* width are represented as a percentage of the original image height and
* width. If this parameter is set to false
then the rendition
* height and width are represented as pixels. This parameter defaults to
* false
.
*/
public static final String PARAM_IS_PERCENT_CROP = "percent_crop";
/**
* This optional {@link String} parameter specifies any additional
* ImageMagick commands, that the user wishes to add. These commands are
* appended after the various crop and resize options.
*/
public static final String PARAM_COMMAND_OPTIONS = "commandOptions";
/*
* @seeorg.alfresco.repo.rendition.executer.ReformatRenderingEngine#
* getTransformOptions
* (org.alfresco.repo.rendition.executer.AbstractRenderingEngine
* .RenderingContext)
*/
@Override
protected TransformationOptions getTransformOptions(RenderingContext context)
{
String commandOptions = context.getCheckedParam(PARAM_COMMAND_OPTIONS, String.class);
ImageResizeOptions imageResizeOptions = getImageResizeOptions(context);
ImageCropOptions cropOptions = getImageCropOptions(context);
ImageTransformationOptions imageTransformationOptions = new ImageTransformationOptions();
imageTransformationOptions.setResizeOptions(imageResizeOptions);
imageTransformationOptions.setCropOptions(cropOptions);
if (commandOptions != null)
{
imageTransformationOptions.setCommandOptions(commandOptions);
}
return imageTransformationOptions;
}
/*
* @seeorg.alfresco.repo.rendition.executer.ReformatRenderingEngine#
* getTargetMimeType
* (org.alfresco.repo.rendition.executer.AbstractRenderingEngine
* .RenderingContext)
*/
@Override
protected String getTargetMimeType(RenderingContext context)
{
String sourceMimeType = context.makeContentReader().getMimetype();
return context.getParamWithDefault(PARAM_MIME_TYPE, sourceMimeType);
}
private ImageResizeOptions getImageResizeOptions(RenderingContext context)
{
int newHeight = context.getIntegerParam(PARAM_RESIZE_WIDTH, -1);
int newWidth = context.getIntegerParam(PARAM_RESIZE_HEIGHT, -1);
if (newHeight == -1 && newWidth == -1)
{
return null; // Image is not being resized!
}
boolean isPercentResize = context.getParamWithDefault(PARAM_IS_PERCENT_RESIZE, false);
boolean maintainAspectRatio = context.getParamWithDefault(PARAM_MAINTAIN_ASPECT_RATIO, false);
ImageResizeOptions imageResizeOptions = new ImageResizeOptions();
imageResizeOptions.setMaintainAspectRatio(maintainAspectRatio);
imageResizeOptions.setWidth(newHeight);
imageResizeOptions.setHeight(newWidth);
imageResizeOptions.setPercentResize(isPercentResize);
return imageResizeOptions;
}
private ImageCropOptions getImageCropOptions(RenderingContext context)
{
int newWidth = context.getIntegerParam(PARAM_CROP_WIDTH, -1);
int newHeight = context.getIntegerParam(PARAM_CROP_HEIGHT, -1);
if (newHeight == -1 && newWidth == -1)
{
return null;
}
int xOffset = context.getIntegerParam(PARAM_CROP_X_OFFSET, 0);
int yOffset = context.getIntegerParam(PARAM_CROP_Y_OFFSET, 0);
boolean isPercentCrop = context.getParamWithDefault(PARAM_IS_PERCENT_CROP, false);
String gravity = context.getCheckedParam(PARAM_CROP_GRAVITY, String.class);
ImageCropOptions cropOptions = new ImageCropOptions();
cropOptions.setGravity(gravity);
cropOptions.setHeight(newHeight);
cropOptions.setPercentageCrop(isPercentCrop);
cropOptions.setWidth(newWidth);
cropOptions.setXOffset(xOffset);
cropOptions.setYOffset(yOffset);
return cropOptions;
}
@Override
protected void checkParameterValues(Action action)
{
// Some numerical parameters should not be zero or negative.
checkNumericalParameterIsPositive(action, PARAM_RESIZE_WIDTH);
checkNumericalParameterIsPositive(action, PARAM_RESIZE_HEIGHT);
checkNumericalParameterIsPositive(action, PARAM_CROP_HEIGHT);
checkNumericalParameterIsPositive(action, PARAM_CROP_WIDTH);
// Target mime type should only be an image MIME type
String mimeTypeParam = (String)action.getParameterValue(PARAM_MIME_TYPE);
if (mimeTypeParam != null && !mimeTypeParam.startsWith("image"))
{
StringBuilder msg = new StringBuilder();
msg.append("Parameter ").append(PARAM_MIME_TYPE)
.append(" had illegal non-image MIME type: ").append(mimeTypeParam);
throw new IllegalArgumentException(msg.toString());
}
}
/**
* This method checks that if the specified parameter is non-null, that it has a
* positive numerical value. That is it is non-zero and positive.
*
* @param action
* @param numericalParamName must be an instance of java.lang.Number or null.
*/
private void checkNumericalParameterIsPositive(Action action, String numericalParamName)
{
Number param = (Number)action.getParameterValue(numericalParamName);
if (param != null && param.longValue() <= 0)
{
StringBuilder msg = new StringBuilder();
msg.append("Parameter ").append(numericalParamName)
.append(" had illegal non-positive value: ").append(param.intValue());
throw new IllegalArgumentException(msg.toString());
}
}
/*
* @seeorg.alfresco.repo.rendition.executer.AbstractRenderingEngine#
* getParameterDefinitions()
*/
@Override
protected Collection