Images

This class contains various SVG and WebP helpers.

Use:
\blobfolio\common\image

clean_svg()

This function cleans up SVG code for safer inline insertion into your document. It fixes some common Illustrator bugs (like broken reference links and the generic id="Layer_1" definition), strips DOCTYPE headers, and reduces whitespace. Many additional options are available (see below).

Note: this requires \DOMDocument support.

Arguments

Type	Description	Notes	Default
string	File path.
array	Options.	See below for details.	NULL
string	Output format.	Either "HTML" or "DATA_URI".	"HTML"

Returns

Returns the SVG source code or FALSE on error.

Example

// Possible arguments.
$args = array(
    // Clean up <style> tag(s): merge tags, group identical rules, clean
    // up formatting.
    'clean_styles'=>false,

    // Build viewBox from width/height or vice versa for every tag which
    // supports viewBox.
    'fix_dimensions'=>false,

    // Set up an xmlns:svg namespace as a workaround for frameworks like
    // Vue.JS which remove stray <style> tags.
    'namespace'=>false,

    // Randomize any ID attributes to ensure that e.g. a million things
    // aren't all named "layer_1".
    'random_id'=>false,

    // Rename and merge all defined classes. For example, an SVG sprite
    // might have a hundred identical classes; this will generate a new
    // class name for each unique rule and remove all others.
    'rewrite_styles'=>false,

    // Remove invalid tags and attributes, strip script-y things, fix
    // formatting, etc. This is the only option enabled by default, and
    // is highly recommended for use on production environments.
    'sanitize'=>true,

    // Cleaning SVGs in PHP can be slow. This option will save the
    // output so on subsequent calls the file can be delivered as-is.
    // The original file is renamed *.dirty.123123123 in case you need
    // to revert.
    'save'=>false,

    // Remove any data-* attributes.
    'strip_data'=>false,

    // Remove all ID attributes.
    'strip_id'=>false,

    // Remove all <style> tags and style/class attributes.
    'strip_style'=>false,

    // Remove all <title> tags.
    'strip_title'=>false,

    // Additional whitelist tags, beyond spec.
    'whitelist_tags'=>array(),

    // Additional whitelist attributes, beyond spec.
    'whitelist_attributes'=>array(),

    // Additional whitelist protocols, beyond http and https.
    'whitelist_protocols'=>array(),

    // Additional whitelist domains, beyond creativecommons.org,
    // inkscape.org, sodipodi.sourceforge.net, w3.org
    'whitelist_domains'=>array()
)

<div class="logo-wrapper">
    <?=\blobfolio\common\image::clean_svg('/path/to/logo.svg')?>    
</div>

getimagesize()

This works very similarly to the native PHP function getimagesize(), except it will also return dimension and type information for SVG and WebP images. Support for other weird formats will likely be added in the future.

Note: This wrapper does not use or populate the optional &$imageinfo argument. It only focuses on sizing.

Arguments

Type	Description	Notes
string	File path.	This must be an image.

Returns

Returns an array containing dimension and type information for the image or FALSE on error. The array formatting is a little obscure, but matches that of the normal getimagesize().

Note: there is no IMAGETYPE_SVG constant, so if an SVG is passed, its type is returned as -1.

Example

The precise data returned varies by environment and format, but positive results should always contain keys 0-3, and almost always mime.

$info = \blobfolio\common\image::getimagesize('file.jpg');
/*
array(
    [0] => 3000                      // Width.
    [1] => 750                       // Height.
    [2] => 2                         // IMAGETYPE_X constant (int).
    [3] => width="3000" height="750" // Width and height as an attribute string.
    [bits] => 8
    [channels] => 3
    [mime] => image/jpeg             // The file's MIME type.
)
*/

has_webp()

Determine whether the system is able to generate WebP images using the cwebp binaries and/or native GD functions. This is not definitive, but provides a good early test for support.

Note: you do not usually need to call this method directly.

Arguments

Type	Description	Default
string	Path to cwebp.	"/usr/bin/cwebp"
string	Path to gif2webp	"/usr/bin/gif2webp"

Returns

Returns FALSE if either binary is missing or unreadable, otherwise TRUE.

svg_dimensions()

Find the native width and height for an SVG. This requires \DOMDocument.

Arguments

Type	Description	Notes
string	SVG.	Either a file path or content.

Returns

Returns an array with "width" and "height" keys or FALSE on failure.

Example

\blobfolio\common\image::svg_dimensions('/path/to/logo.svg');
/*
array(
    [width] => 555.3,
    [height] => 30
)
*/

to_webp()

Generate a WebP from a JPEG, PNG, or GIF source.

For performance and quality reasons, it is recommended you install native cwebp and gif2webp binaries on your server and make them accessible to PHP. But if that can't happen, GD will be used as a fallback (if present).

Arguments

Type	Description	Notes	Default
string	Source path.
string	Output path.	If NULL, the source path (with a swapped extension) will be used.	NULL
string	Path to cwebp.		"/usr/bin/cwebp"
string	Path to gif2webp		"/usr/bin/gif2webp"
bool	Refresh.	If TRUE, the image will be rebuilt if it already exists.	FALSE

Returns

Returns TRUE if the output file exists at the end of the process, otherwise FALSE.