How to Optimize Images on Your Website is a tutorial that will guide you through the method. Once completed, you'll have a better understanding why and how search engine optimizing your website images is extremely important.
What is Image Optimization?
Image SEO is a means or art used web developers for reducing the image file size without sacrificing the image quality. And doing so helps increases your site load time due to fewer bytes getting downloaded by your browser. Simple enough, right?
Think about the last time you visited a website that took a long time to load onto your device? Did you wait for the site to finish loading, or did you leave before the web browser completed the task?
If you are like most people, you abandon that website in a hurry. Do you have the time to wait for a slow loading image or page? For heaven sake, no.
Website traffic laws are photo enforced. Therefore, a website that takes a long time to load can and will cost you website visitors.
Choosing the image size doesn't actually compress it, you need a plugin or image compression tool such as Tinypng, which I prefer. as it saves installing another plugin. I did some training on Tinypng which may interest you. Compressing Images Using Tinypng Reducing the size of the image to what you require before compressing is always a good idea. You can also ensure that your image remains the size you have chosen.
By going to your Dashboard>Setting>Media and entering a 0 digit in all three sizes: Thumbnail, Medium, and Large, and checking the box Crop Thumbnails, your image will remain the size exactly as chosen without the need to change it in the image size drop down menu.
If you do need to change the size you can edit it in the visual editor.
JPEG is fine if you're using images "as is",but if your using layers to build an image you need PNG, as JPEG doesn't support transparencies..
There are differences of opinion on using keywords in the title and alt text. Some believe Google may class it as "Keyword Stuffing".
I always aim to keep keywords at no more than three percent in the content, this allows me to use the keywords in the alt text and still remain within the recommended maximum of five percent. Yoast SEO will give you an indication of percentage of keywords in your content.
Hope this helps. Best wishes.
Xav.