Why we built our own image optimizer and PDF flipbook maker

Two jobs come up again and again in our web work. Images arrive far too big for a web page, and print brochures need to go online as something better than a PDF link. We built a tool for each: Pixel Presser, a free Mac app, and flipbook-maker, which turns a PDF into a web flipbook.

Pixel Presser: smaller images, kept on your Mac

A photo from a phone or a designer can run to several megabytes. Put a dozen of those on a page and visitors wait, especially on a phone. Pixel Presser started as our own take on the drag-and-drop image optimizers we'd used on the Mac, such as Optimage.

You drop images or a whole folder onto its window, its Dock icon or its menu-bar icon, and it works through the batch:

• Converts to WebP, a web image format that's usually smaller than JPEG or PNG at the same quality. It can also save JPEG, PNG or HEIC, or keep each file's own format.
• Resizes oversized images to a maximum width, height or longest edge.
• Compresses to the quality level you set, so you decide how much detail to trade for size.
• Strips metadata, the hidden camera details and sometimes the location a photo carries.
• Saves beside the originals or into a folder you pick, and warns you before it overwrites anything.
• Shows before and after side by side, so you can check a result before you use it.

The work happens on your Mac. Your images never go to an online compressor, which matters when they're client work or not public yet. Pixel Presser handles several images at once and includes Google's WebP encoder, so you have nothing else to install.

It's free from pixelpresser.com and runs on macOS 14 or later on an Apple Silicon Mac. We sign each release with our Apple developer certificate and Apple checks it (notarization), so your Mac opens it without a security warning.

flipbook-maker: print PDFs as web flipbooks

A sports and entertainment client of ours publishes guides to its premium seating each season. Their print designer lays them out as PDFs, which had been going online through FlowPaper, a flipbook service. In September 2026 we built flipbook-maker to replace it and keep the designer's layout exactly as designed.

flipbook-maker turns a print-ready PDF into a flipbook, a book you page through in the browser. The result is one folder of ordinary files with no service behind it, and any web host can serve it.

Sharp at any zoom

It splits each page into two layers:

• A picture layer: the page's photos and artwork with the text taken out, saved as WebP at three sizes. Each browser loads the size that suits its screen, and a sharper one when you zoom in.
• A text layer: the words drawn as vector shapes (outlines rather than pixels) taken from the PDF's own fonts. The text stays crisp at 500% zoom, and the designer's licensed typefaces look the same on every device without the font files ever going online.

Then it checks its own work. It compares each finished page with the original PDF, and if the two don't match, it uses a plain image of that page instead. Readers see the page the designer made.

What readers get

• A book that opens as a closed hardcover, with pages that curl as you turn them by click, swipe, arrow key or by dragging a corner.
• Real text: you can search it, select and copy it, and read it with a screen reader.
• Working links. The PDF's own links carry over, and email addresses, phone numbers and web addresses typed as plain text become links too.
• A contents list, page thumbnails, zoom, full screen, a PDF download and a share link to the page you're on.
• On a phone, the open book fills the screen's width. Tap a page to read it at full width and swipe to turn.

Publishing in one step

One command builds every PDF waiting in a folder, uploads each book to the client's web server and lists the new links, ready to paste into an email. A new edition can replace an old book at the same web address, so links people already have keep working. Each build stamps its files with a new version, so a new edition's pages never come from an old copy saved in someone's browser.

What we get from owning these tools

• The client keeps the files. A flipbook is a folder on the client's own server. It stays up as long as their web host does, with no service account behind it.
• Files stay on our machines. Pixel Presser does its work on the Mac in front of you, so client images don't pass through anyone else's servers.
• We fix what bothers us. We made 65 changes to flipbook-maker in its first three days, most of them to how the book looks and moves.

We're turning flipbook-maker into a Mac app next. We'll write about that version when it's ready.