WordPress.org

Basic Plug-in Usage:

Install and activate the plug-in. Use the shortcode [wcs_qr_code] anywhere in a post/page or in a text widget to generate a QR Code image.

Standard WordPress installation procedure:

1. Download the ZIP file to your local computer.
2. Unzip the file's contents.
3. Login as an administrator to your WordPress website.
4. Upload the wcs-qr-code-generator directory to your /wp-content/plugins/ directory.
5. Activate the plugin through the WordPress Dashboard->Plugins menu.

Basic Shortcode Usage syntax:

[wcs_qr_code]

Example Shortcode Usage:

[wcs_qr_code url='now is the time' size='128' color='darkblue']

Shortcode Usage Information:

1. url is the content for the qr code image (defaults to the current page/post url) -- more on this below
2. size is square image's size in pixels (default is '100')
3. color can be a 6-digit hex color value or an HTML color name (default is 'black')
4. ecl is the error correction level (default is 'L|4') -- more on this below
5. shorten is a toggle for shortening the url (default is 'false')
6. format is the image format (PNG or JPG) (default is 'png')
7. tooltip is the image's tooltip text (default is none)

ECL Details:

This plug-in utilizes the Google Charts API. You can view the various ECL settings here.

Essentially, the ECL code consists of two components: (1) the error correction level (L, M, Q, or H), and (2) the white border row/column width (1 - 40 rows, not pixels).

URL Details:

If omitted, the URL defaults to the current page/post url. You can also use any valid url or text (within the character limitation of the selected ECL attribute value).

When using an email address, a standard format is expected. For example me@here.com should be implemented as mailto:me@here.com.

Telephone numbers also have a standardized format. For example, 212-555-1212 should be implemented as tel:+12125551212.

An SMS link is encoded in a fashion similar to an email address. For example, a link to the number 12345 should be implemented as sms:12345.

These and many other possibilities are explained in detail here.