BlibBlob — User Manual

Convert images to another format, resize, rotate, rename and watermark them — many at once. This manual describes everything the app can do, in the order you will usually need it.

1 — First launch

BlibBlob has a single window with three parts: the list of images on the left, the settings for the result on the right, and the footer at the bottom with the Convert button.

The BlibBlob window: on the left the list of images with the columns File, Resolution, Target format and Target resolution; on the right the settings for output format, size, resolution and destination folder; at the bottom the footer with the Convert button. — On the left the images with their resolution and what they will turn into. On the right the settings. At the top the buttons for adding images, for presets and for the app settings.

The workflow is always the same: add images, set on the right what they should become, convert. The originals stay untouched — BlibBlob always writes new files.

For each image the list shows the file name, the source resolution, the target format and the target resolution. The two target columns follow every change on the right immediately, so you can see what will happen to each image before converting.

2 — Adding images

There are three ways:

Drag images from the Finder into the window.
Click Images at the top and pick them in the dialog.
Click + Folder at the top to load all images of a folder at once. This is a feature of the full version.

Whether subfolders are searched as well when loading a folder is set under Settings › General › Include subfolders.

Formats BlibBlob reads

PNG, JPEG, HEIC, TIFF, WebP, GIF, BMP, AVIF, SVG, the RAW formats of common cameras (CR2, CR3, NEF, ARW, DNG, RAF, ORF), PSD and OpenEXR.

Removing images

Select images and press ⌘ ⌫, or choose Remove from list in the context menu.
Clear list at the top removes all images from the list.

Removing only affects the list. The files on your Mac stay where they are.

Thumbnails in the list

With Settings › General › Show preview images every row gets a small image. With a very large number of images the list then takes a little longer to load.

3 — Format, size and destination

Output format

BlibBlob writes PNG, JPEG, HEIC, TIFF, WebP, AVIF, PDF and EPS.

Format	Quality slider	Transparency
PNG, TIFF	no — lossless	kept
HEIC, WebP, AVIF	yes	kept
JPEG	yes	removed, white background
PDF, EPS	yes — for the embedded JPEG	removed, white background

The quality slider only appears for formats that support it. Higher quality means larger files.

Size

Under Mode there are five options:

Original: The pixel dimensions stay as they are.
Longest edge: The longer side is set to the value you enter, the other follows in proportion. This mode only shrinks: an image that is already smaller stays unchanged. It is meant as an upper limit, such as “nothing above 1920 pixels”.
Exact (W × H): You enter width and height. With Scale proportionally the value you changed last leads, and the other one is calculated for each image.
Width only: The width is fixed, the height follows in proportion.
Height only: The height is fixed, the width follows in proportion.

“Exact”, “Width only” and “Height only” both shrink and enlarge.

Numbers take effect with Return

A typed value applies once you press Return or Tab or click into another field. Until then the target columns on the left do not change.

Resolution and alpha

DPI sets the resolution the image is tagged with for printing: 72 for web and screen, 144 for Retina, 300 for print, or a value of your own. This does not change the pixels, only the stated print size. WebP and PDF do not store a dpi value.

Remove alpha channel (white background) fills transparent areas with white. For JPEG, PDF and EPS this always happens, because these formats have no transparency.

Destination folder

Source Folder: Each converted image is saved next to its original. The first time, BlibBlob asks whether it may write to that folder — macOS requires this for apps from the App Store. Confirming once is enough.
Custom Folder: All results go into one folder that you set with Choose folder…. Without a chosen folder, converting is not possible.

4 — All images or only selected ones

The settings on the right apply to all images in the list as long as none is selected. When images are selected, they apply only to the selected ones. This way different images in one list can get different formats or sizes:

Select the first images, set format and size.
Select the next images, set other values.
Convert.

Selection works as in the Finder: click, ⇧-click for a range, ⌘-click for single images. The footer shows how many images are selected next to the total. Selected rows carry a narrow bar in the accent colour on the left.

Images that have already been converted stay untouched when you change something on the right.

5 — Editing single images

A right-click on an image opens the context menu:

Show values: Shows what this image will be converted with: format, quality, target resolution, dpi, alpha channel, rotation and watermark. For dpi and alpha it also says whether the value applies to this image only or to all images.
Rotate: 90° right, 90° left or 180°.
Flip: Horizontal or vertical.
Reset transformation: Undoes rotating and flipping.
Watermark: Assigns a watermark to the image or removes it. See Watermarks.
Output name: Sets for this image whether it follows the default, is renamed or keeps its name. See Output names.
Show in Finder: Opens the folder containing the original file.
Remove from list: Takes the image out of the list; the file stays.

If you right-click one of several selected images, the commands apply to all selected images.

6 — Converting

Convert at the bottom right starts the work, or ⌘ ↩ on the keyboard. If images are selected, only those are converted.

Each row shows its state:

Waiting — not yet processed.
Converting… — being processed right now.
Done — the new file has been written.
Error — followed by the reason.

Afterwards the footer shows how many images were converted and how much space was saved — or how much larger the files have become, for instance when converting to PNG.

Reconvert sets finished images back to “Waiting”. This lets you run the same list again with other settings.

When a step fails

If a watermark cannot be applied or an image cannot be brought to the target size, BlibBlob writes no file for that image. The row shows an error instead. So you never get a result that is silently missing something.

Metadata

By default BlibBlob removes all metadata: camera, capture date and above all the GPS location. That is handy when the images are going online. In the full version you can choose under Settings › Advanced › EXIF Metadata to keep everything or remove only GPS.

7 — Presets

A preset is a saved combination of format, quality, size, dpi and the alpha setting. The destination folder is not part of it. The Presets menu at the top contains three templates:

Template	Format	Size	Quality	dpi
Web (WebP)	WebP	longest edge 1920 px	80 %	72
E-Mail	JPEG	longest edge 1200 px	70 %	72
Druck (300 dpi)	TIFF	Original	—	300

The template names are the same in every language; “Druck” is German for print. Clicking a preset copies its values into the settings on the right — as always for the selected images or, without a selection, for all.

Your own presets

In the full version Save current settings… stores the current values under a name. The dialog lists your existing presets above the name field; a click takes over a name. If the name already exists, the button reads Overwrite. Delete a preset via Presets › Delete preset. The three templates cannot be deleted.

8 — Watermarks

Watermarks are part of the full version. Their button appears at the top of the window once you have switched on Settings › Advanced › Enable watermarks.

The Watermarks window: on the left the list of watermarks, on the right the settings for text, font, size, colour, position and rotation with a preview. — On the left your watermarks, on the right the settings of the selected one with its preview.

Create a new one with + below the list. Every watermark is either a text or an image, such as a logo or a signature.

Watermark settings

Name: How it appears in the list and in the context menu.
Active: Only active watermarks can be assigned to images. Unfinished ones are kept out of the menu that way.
Text and font: The text may span several lines; a new line is entered with ⌥ ↩.
Image: Transparent PNGs with an alpha channel look best.
Size: Relative grows with the image — the watermark looks the same size on small and large images. Pixels uses a fixed value.
Colour and opacity: White with some transparency works on most images.
Position: One of nine standard positions with a 5 % margin to the edge — or Custom with your own X and Y values.
Rotation: Preset angles or any value with the slider: 0° is horizontal, 45° the classic diagonal, 90° vertical.

The preview gives an approximate impression. The actual size and position depend on each image.

Assigning a watermark

Select images, right-click, Watermark, choose the one you want. The same menu removes it again with Remove watermark.

9 — Output names

By default every image keeps its name and only gets the new extension. In the full version BlibBlob renames the results consistently. The button appears at the top once you have switched on Settings › Advanced › Enable output names.

BlibBlob settings in the Advanced section: the cards Lists feature, Output names and Image preview, each with a description and a switch turned on. — Under Advanced every full-version feature has its own switch. Only when it is on does its button appear in the main window.

The Output names window above the main window, with default behaviour, base name and date. — The Output names window. Further down follow the sequence number and an example of what the names will look like.

Base name: The fixed part, for example “Holiday”.
Date: Either today’s date or the capture date, in the format YYYY-MM-DD — so the files sort chronologically. Without a capture date BlibBlob uses the file’s modification date, otherwise today’s.
Sequence number: The number of digits. If they are not enough, BlibBlob simply keeps counting.
Default behaviour: Rename or Source name — applies to all images.

Per image this can be overridden in the context menu Output name: Follow default, Rename or Keep source name.

10 — Image preview

The image preview shows before converting what the result will look like — on its own or side by side with the original. It is part of the full version and is switched on under Settings › Advanced › Enable image preview. Every row then gets an eye in front; clicking it opens the preview.

Fit shows the whole image. Switched to 100 % and scrolled, you can judge details and compression artefacts — useful for finding the lowest quality that still looks good.

11 — Lists and session

Remember session

With Settings › Advanced › Remember conversion list on quit BlibBlob saves the list with all its settings — rotation, watermark, target format — when quitting and restores it at the next launch.

Exporting and importing lists

After switching on Settings › Advanced › Enable Lists feature the Lists button appears at the top. It saves the current list as a .bblist file and loads it again later — for instance separate lists for “Wedding photos” and “Product shots”. Importing replaces the current list; BlibBlob asks first.

Same Mac only

A list contains no images, only references to them, together with the permission from macOS to read them. That permission only holds on the Mac where the list was created. Images that are no longer there when loading are silently dropped from the list.

12 — SVG and EPS

SVG as a source

SVG files are vector graphics without a fixed pixel size. BlibBlob rasterises them when converting:

If a target size is set, the image is created directly at that size — without the quality loss of enlarging afterwards.
If the size is set to Original, the size given in the SVG file applies.

EPS as a target

EPS behaves like PDF: the image is embedded as a JPEG, the quality slider applies to that JPEG, and transparent areas become white.

13 — Settings

The gear at the top of the window or ⌘ , opens the settings.

General: Thumbnails in the list, subfolders when loading folders, and a note on how metadata is handled.
Conversion: The WebP speed: Fast for many images at once, Balanced for most cases, Smaller for the most compact files at the cost of longer processing. Image quality is not affected.
Advanced: The full-version features: EXIF metadata, image preview, lists feature, output names, watermarks, remember session. Each one is switched on here individually; only then does its button appear in the main window.
Appearance: Light, dark or following the system, plus one of twelve accent colours.
Language: The language of the app, independent of the system language. The change takes effect immediately.
Log File: Writes processes and errors to a file, at a level of your choice. Show lets you read and copy it, Show in Finder locates it. When contacting support, this file helps most.
Full Version: Status, purchase and Restore Purchase.
About: Version, the supported formats and the What’s New window.

14 — Free version and full version

Converting, resizing, rotating, flipping, the three preset templates and all formats are available without a purchase. The full version is a one-time purchase without a subscription and permanently unlocks:

Remember conversion list
Export and import lists
Consistent output names
Image preview before converting
Text and image watermarks
Import folders
Create your own presets
Choice of which metadata is kept

Purchase it under Settings › Full Version. On another Mac with the same Apple ID, Restore Purchase there is enough.

15 — Frequently asked questions

I changed something on the right, but the list shows the old values.

Two possible reasons. Typed numbers only apply after Return or Tab. And images that have already been converted no longer follow the settings — Reconvert resets them.

My image does not get larger with “Longest edge”.

That is intended: this mode only shrinks. To enlarge, use “Exact”, “Width only” or “Height only”.

Why does my JPEG suddenly have a white background?

JPEG has no transparency; transparent areas become white. For transparency choose PNG, HEIC, WebP, AVIF or TIFF.

Where is the GPS data of my photos in the result?

By default nowhere — BlibBlob removes it. In the full version this can be changed under Settings › Advanced.

A button from this manual is missing in the window.

Watermarks, output names, lists and the image preview only appear once they are switched on under Settings › Advanced.

How do I get the “What’s New” window back?

Under Settings › About.