The default product gallery in Odoo 10 is Responsive, has a slider function and is controlled directly from the backend. Product images can only be uploaded from the computer and come directly into the database. Also the adding of the important Alt-Tag happens in the backend. How it works, we show in the following section.
ADD PICTURES AND ALT-TAG
The first step is to go to the Odoo backend for a product. The main product image, which you can see next to the product name, is also the first gallery image in the online shop. To add more product images, go to the "Images" tab and then the "create" button.
In the newly opened window, go to the image icon and upload the product image. Then enter a short description of the image content in "Image Name", which generates the Alt-Tag for the product image - why this is very important, we explain in the next paragraph. Now that you have entered the Alt-Tag, you can save and add more product images. The new product images will be displayed on the product page from this point on.
SEARCH ENGINE OPTIMIZATION
Among the many ranking factors for search engines and image search engines, the Alt-Tag (Alt attribute) is one of the most important for images. The alt text has the task of describing the content of the image and therefore also serves the accessibility. The following is a small summary of the alt text.
Using a screen reader, blind people can read texts on web pages. This also works for pictures, since the alt text is also read out and describes the picture content.
Image search engines read the alt text to display the most relevant images for searches. Online shops have the opportunity to sell products through good placements in this way.
Also, the alt text is used by search engines to better assess the overall context of a website - what leads to better rankings in the search engines.
Furthermore, the alt text is displayed on web pages if the image is not yet loaded or is not available.
This is what the alt text in the code looks like:
<img src=/web/image/product/image" alt="I am the description of the image">
What we have still to consider?
Next to the Alt-Tag is more to consider to influence users and search engines. First of all, product images should have a very good quality to convince consumers of the quality of the product. Furthermore, the image format JPEG should be used (instead of PNG) in order to have the smallest possible file size. Also, product images, in terms of mobile optimization, should be sized to be sharply displayed on smartphones too (larger scaled images just look unprofessional).
Very important: the name of the image file is just as important as the Alt-Tag itself and should be as similar as possible.