Beware! These kind of images is also known as "inline images".
Lotus Notes can import images to rich text fields through the Notes client or via the C/C++ API. If the imported image is a GIF or a JPG, Notes will fortunately store the image within the Note in its original format. If the image is anything else, Notes will convert the imported image to a stripped down TIFF variant.
The Notes client also accept images through copy and paste. When you for example see an image on a web page and copy that to the clipboard, you can easily paste the image into a rich text fields in Notes. The pasted image is however converted to the stripped down TIFF version at paste-time!
Unfortunately you can't really do much with embedded images in the Notes client. You don't have any options to view or save the images as files. You need special tools, such as List Fields to export and make such images available again.
Let's have a look at a sample. In the Notes document below, a winter-image has been imported into Lotus Notes:
If you right-click on the image, you won't get any "image properties" or similar. If you look at the Notes document with NotesPeek, you can see deep down in the graphic-related CD-records that you have a JPG, GIF or other image. Below you see how to identify the image type with NotesPeek:
Below you see what the same screenshot looks like when you have an unknown image:
From the CD-records you can't exactly tell what kind of image this originally was. We do see however, several data about the image. And when we know that such images are a stripped down version of TIFF, we are able through some serious programming to decode the image into something that we can view, edit or save. This is how List Fields process these images