That still won't detect bots. If you build a click-bot, you're probably only going to click the link and download the source. You wouldn't care about loading any images so the 1x1 pixel image still won't track the page load.
To track bots effectively, you need to check your server logs. In fact, you could build a strong case for a bot click if the requesting IP pulled the source HTML but didn't follow up with any image requests from the page. Not loading images is typical bot behavior.
To track bots effectively, you need to check your server logs. In fact, you could build a strong case for a bot click if the requesting IP pulled the source HTML but didn't follow up with any image requests from the page. Not loading images is typical bot behavior.