Your finished archive
Are videos handled too, or only photos?
Both photos and videos. Videos get their original date and position back just like stills, and the sound is left alone.
Both, and they are treated the same way. Videos get their original date and their position back exactly as stills do, and they get the same clean filenames and the same place in the folder structure. A clip from a night out in 2019 lands in the folder for that month, named after the moment it was recorded, and shows up on the right day in your photo app rather than on the day you downloaded the export. Nothing about the way videos are treated is a second-class version of what happens to photos, and nothing is skipped because a clip is long or large.
Video is the heavier part of the job, and that is why a video-heavy archive takes longer than an archive of mostly photos even when they weigh the same number of gigabytes. It is also why we do not promise a particular processing time: two archives of 30 GB can differ considerably depending on what is in them. Filming in high resolution is what fills a Memories archive fastest, so for many people the videos are the bulk of the work even when they are a minority of the files.
The quality is preserved. We do not re-encode your clips into a smaller format to save time, and the sound comes along as it is. We do not touch the audio track. The summary you get afterwards counts videos and photos together, so you can see how many of each got their date and their location back before you import anything.