image.effects.inc

<?php


/**
 * @file
 * Functions needed to execute image effects provided by Image module.
 */

/**
 * Implements hook_image_effect_info().
 */
function image_image_effect_info() {
    $effects = array(
        'image_resize' => array(
            'label' => t('Resize'),
            'help' => t('Resizing will make images an exact set of dimensions. This may cause images to be stretched or shrunk disproportionately.'),
            'effect callback' => 'image_resize_effect',
            'dimensions callback' => 'image_resize_dimensions',
            'form callback' => 'image_resize_form',
            'summary theme' => 'image_resize_summary',
        ),
        'image_scale' => array(
            'label' => t('Scale'),
            'help' => t('Scaling will maintain the aspect-ratio of the original image. If only a single dimension is specified, the other dimension will be calculated.'),
            'effect callback' => 'image_scale_effect',
            'dimensions callback' => 'image_scale_dimensions',
            'form callback' => 'image_scale_form',
            'summary theme' => 'image_scale_summary',
        ),
        'image_scale_and_crop' => array(
            'label' => t('Scale and crop'),
            'help' => t('Scale and crop will maintain the aspect-ratio of the original image, then crop the larger dimension. This is most useful for creating perfectly square thumbnails without stretching the image.'),
            'effect callback' => 'image_scale_and_crop_effect',
            'dimensions callback' => 'image_resize_dimensions',
            'form callback' => 'image_resize_form',
            'summary theme' => 'image_resize_summary',
        ),
        'image_crop' => array(
            'label' => t('Crop'),
            'help' => t('Cropping will remove portions of an image to make it the specified dimensions.'),
            'effect callback' => 'image_crop_effect',
            'dimensions callback' => 'image_resize_dimensions',
            'form callback' => 'image_crop_form',
            'summary theme' => 'image_crop_summary',
        ),
        'image_desaturate' => array(
            'label' => t('Desaturate'),
            'help' => t('Desaturate converts an image to grayscale.'),
            'effect callback' => 'image_desaturate_effect',
            'dimensions passthrough' => TRUE,
        ),
        'image_rotate' => array(
            'label' => t('Rotate'),
            'help' => t('Rotating an image may cause the dimensions of an image to increase to fit the diagonal.'),
            'effect callback' => 'image_rotate_effect',
            'dimensions callback' => 'image_rotate_dimensions',
            'form callback' => 'image_rotate_form',
            'summary theme' => 'image_rotate_summary',
        ),
    );
    return $effects;
}

/**
 * Image effect callback; Resize an image resource.
 *
 * @param $image
 *   An image object returned by image_load().
 * @param $data
 *   An array of attributes to use when performing the resize effect with the
 *   following items:
 *   - "width": An integer representing the desired width in pixels.
 *   - "height": An integer representing the desired height in pixels.
 *
 * @return
 *   TRUE on success. FALSE on failure to resize image.
 *
 * @see image_resize()
 */
function image_resize_effect(&$image, $data) {
    if (!image_resize($image, $data['width'], $data['height'])) {
        watchdog('image', 'Image resize failed using the %toolkit toolkit on %path (%mimetype, %dimensions)', array(
            '%toolkit' => $image->toolkit,
            '%path' => $image->source,
            '%mimetype' => $image->info['mime_type'],
            '%dimensions' => $image->info['width'] . 'x' . $image->info['height'],
        ), WATCHDOG_ERROR);
        return FALSE;
    }
    return TRUE;
}

/**
 * Image dimensions callback; Resize.
 *
 * @param $dimensions
 *   Dimensions to be modified - an array with components width and height, in
 *   pixels.
 * @param $data
 *   An array of attributes to use when performing the resize effect with the
 *   following items:
 *   - "width": An integer representing the desired width in pixels.
 *   - "height": An integer representing the desired height in pixels.
 */
function image_resize_dimensions(array &$dimensions, array $data) {
    // The new image will have the exact dimensions defined for the effect.
    $dimensions['width'] = $data['width'];
    $dimensions['height'] = $data['height'];
}

/**
 * Image effect callback; Scale an image resource.
 *
 * @param $image
 *   An image object returned by image_load().
 * @param $data
 *   An array of attributes to use when performing the scale effect with the
 *   following items:
 *   - "width": An integer representing the desired width in pixels.
 *   - "height": An integer representing the desired height in pixels.
 *   - "upscale": A boolean indicating that the image should be upscaled if the
 *     dimensions are larger than the original image.
 *
 * @return
 *   TRUE on success. FALSE on failure to scale image.
 *
 * @see image_scale()
 */
function image_scale_effect(&$image, $data) {
    // Set sane default values.
    $data += array(
        'width' => NULL,
        'height' => NULL,
        'upscale' => FALSE,
    );
    if (!image_scale($image, $data['width'], $data['height'], $data['upscale'])) {
        watchdog('image', 'Image scale failed using the %toolkit toolkit on %path (%mimetype, %dimensions)', array(
            '%toolkit' => $image->toolkit,
            '%path' => $image->source,
            '%mimetype' => $image->info['mime_type'],
            '%dimensions' => $image->info['width'] . 'x' . $image->info['height'],
        ), WATCHDOG_ERROR);
        return FALSE;
    }
    return TRUE;
}

/**
 * Image dimensions callback; Scale.
 *
 * @param $dimensions
 *   Dimensions to be modified - an array with components width and height, in
 *   pixels.
 * @param $data
 *   An array of attributes to use when performing the scale effect with the
 *   following items:
 *   - "width": An integer representing the desired width in pixels.
 *   - "height": An integer representing the desired height in pixels.
 *   - "upscale": A boolean indicating that the image should be upscaled if the
 *     dimensions are larger than the original image.
 */
function image_scale_dimensions(array &$dimensions, array $data) {
    if ($dimensions['width'] && $dimensions['height']) {
        image_dimensions_scale($dimensions, $data['width'], $data['height'], $data['upscale']);
    }
}

/**
 * Image effect callback; Crop an image resource.
 *
 * @param $image
 *   An image object returned by image_load().
 * @param $data
 *   An array of attributes to use when performing the crop effect with the
 *   following items:
 *   - "width": An integer representing the desired width in pixels.
 *   - "height": An integer representing the desired height in pixels.
 *   - "anchor": A string describing where the crop should originate in the form
 *     of "XOFFSET-YOFFSET". XOFFSET is either a number of pixels or
 *     "left", "center", "right" and YOFFSET is either a number of pixels or
 *     "top", "center", "bottom".
 * @return
 *   TRUE on success. FALSE on failure to crop image.
 * @see image_crop()
 */
function image_crop_effect(&$image, $data) {
    // Set sane default values.
    $data += array(
        'anchor' => 'center-center',
    );
    list($x, $y) = explode('-', $data['anchor']);
    $x = image_filter_keyword($x, $image->info['width'], $data['width']);
    $y = image_filter_keyword($y, $image->info['height'], $data['height']);
    if (!image_crop($image, $x, $y, $data['width'], $data['height'])) {
        watchdog('image', 'Image crop failed using the %toolkit toolkit on %path (%mimetype, %dimensions)', array(
            '%toolkit' => $image->toolkit,
            '%path' => $image->source,
            '%mimetype' => $image->info['mime_type'],
            '%dimensions' => $image->info['width'] . 'x' . $image->info['height'],
        ), WATCHDOG_ERROR);
        return FALSE;
    }
    return TRUE;
}

/**
 * Image effect callback; Scale and crop an image resource.
 *
 * @param $image
 *   An image object returned by image_load().
 * @param $data
 *   An array of attributes to use when performing the scale and crop effect
 *   with the following items:
 *   - "width": An integer representing the desired width in pixels.
 *   - "height": An integer representing the desired height in pixels.
 * @return
 *   TRUE on success. FALSE on failure to scale and crop image.
 * @see image_scale_and_crop()
 */
function image_scale_and_crop_effect(&$image, $data) {
    if (!image_scale_and_crop($image, $data['width'], $data['height'])) {
        watchdog('image', 'Image scale and crop failed using the %toolkit toolkit on %path (%mimetype, %dimensions)', array(
            '%toolkit' => $image->toolkit,
            '%path' => $image->source,
            '%mimetype' => $image->info['mime_type'],
            '%dimensions' => $image->info['width'] . 'x' . $image->info['height'],
        ), WATCHDOG_ERROR);
        return FALSE;
    }
    return TRUE;
}

/**
 * Image effect callback; Desaturate (grayscale) an image resource.
 *
 * @param $image
 *   An image object returned by image_load().
 * @param $data
 *   An array of attributes to use when performing the desaturate effect.
 * @return
 *   TRUE on success. FALSE on failure to desaturate image.
 * @see image_desaturate()
 */
function image_desaturate_effect(&$image, $data) {
    if (!image_desaturate($image)) {
        watchdog('image', 'Image desaturate failed using the %toolkit toolkit on %path (%mimetype, %dimensions)', array(
            '%toolkit' => $image->toolkit,
            '%path' => $image->source,
            '%mimetype' => $image->info['mime_type'],
            '%dimensions' => $image->info['width'] . 'x' . $image->info['height'],
        ), WATCHDOG_ERROR);
        return FALSE;
    }
    return TRUE;
}

/**
 * Image effect callback; Rotate an image resource.
 *
 * @param $image
 *   An image object returned by image_load().
 * @param $data
 *   An array of attributes to use when performing the rotate effect containing
 *   the following items:
 *   - "degrees": The number of (clockwise) degrees to rotate the image.
 *   - "random": A boolean indicating that a random rotation angle should be
 *     used for this image. The angle specified in "degrees" is used as a
 *     positive and negative maximum.
 *   - "bgcolor": The background color to use for exposed areas of the image.
 *     Use web-style hex colors (#FFFFFF for white, #000000 for black). Leave
 *     blank for transparency on image types that support it.
 * @return
 *   TRUE on success. FALSE on failure to rotate image.
 * @see image_rotate().
 */
function image_rotate_effect(&$image, $data) {
    // Set sane default values.
    $data += array(
        'degrees' => 0,
        'bgcolor' => NULL,
        'random' => FALSE,
    );
    // Convert short #FFF syntax to full #FFFFFF syntax.
    if (strlen((string) $data['bgcolor']) == 4) {
        $c = $data['bgcolor'];
        $data['bgcolor'] = $c[0] . $c[1] . $c[1] . $c[2] . $c[2] . $c[3] . $c[3];
    }
    // Convert #FFFFFF syntax to hexadecimal colors.
    if ($data['bgcolor'] != '') {
        $data['bgcolor'] = hexdec(str_replace('#', '0x', $data['bgcolor']));
    }
    else {
        $data['bgcolor'] = NULL;
    }
    if (!empty($data['random'])) {
        $degrees = abs((double) $data['degrees']);
        $data['degrees'] = rand(-1 * $degrees, $degrees);
    }
    if (!image_rotate($image, $data['degrees'], $data['bgcolor'])) {
        watchdog('image', 'Image rotate failed using the %toolkit toolkit on %path (%mimetype, %dimensions)', array(
            '%toolkit' => $image->toolkit,
            '%path' => $image->source,
            '%mimetype' => $image->info['mime_type'],
            '%dimensions' => $image->info['width'] . 'x' . $image->info['height'],
        ), WATCHDOG_ERROR);
        return FALSE;
    }
    return TRUE;
}

/**
 * Image dimensions callback; Rotate.
 *
 * @param $dimensions
 *   Dimensions to be modified - an array with components width and height, in
 *   pixels.
 * @param $data
 *   An array of attributes to use when performing the rotate effect containing
 *   the following items:
 *   - "degrees": The number of (clockwise) degrees to rotate the image.
 *   - "random": A boolean indicating that a random rotation angle should be
 *     used for this image. The angle specified in "degrees" is used as a
 *     positive and negative maximum.
 */
function image_rotate_dimensions(array &$dimensions, array $data) {
    // If the rotate is not random and the angle is a multiple of 90 degrees,
    // then the new dimensions can be determined.
    if (!$data['random'] && (int) $data['degrees'] == $data['degrees'] && $data['degrees'] % 90 == 0) {
        if ($data['degrees'] % 180 != 0) {
            $temp = $dimensions['width'];
            $dimensions['width'] = $dimensions['height'];
            $dimensions['height'] = $temp;
        }
    }
    else {
        $dimensions['width'] = $dimensions['height'] = NULL;
    }
}