Optimisation and image editor

Besides cleaning up, Media Organizer can also shrink and edit images. Both are reversible and run strictly locally — no image is sent to an online service.

The optimisation report

The report shows images with optimisation potential, measured against the thresholds from the options. It is a recommendation — nothing is changed until you trigger it.

Typical reasons:

• Too large (file size) — exceeds the configured maximum file size (default 500 KB).
• Too large (dimensions) — exceeds the maximum edge length (default 2500 px).
• Not a modern format (WebP/AVIF) — a raster image that would be considerably smaller as WebP or AVIF.
• Outdated format — BMP or TIFF, for instance.

Two groups — and the difference matters

The report deliberately separates them:

Triggering optimisation

Select the files and click Optimise. Before that the following applies:

• The original is backed up (default: jimgo_optimize_backup, outside the web).
• Nothing is ever scaled up — only down.
• If the optimisation brings less than the minimum saving (default 10 %), the original stays untouched. No loss of quality for a few kilobytes.
• Protected files (safelist) stay untouched and are shown as such in the confirmation dialog.

The images are processed one after another, with a progress display. How long one run lasts before the next begins is set under Options → Optimisation → Time per step. The image already started is always finished.

Via Backups you reach the saved originals and can undo an optimisation.

Optimising from "All files"

The report measures against the configured thresholds — it shows what the extension considers worth optimising. Sometimes you know better: you sort All files by size, see your largest images and want to shrink exactly those.

You can do that right there. Tick the boxes, click Optimise — it is the same backed-up, reversible operation as in the report, with the same settings.

Two differences from the report:

• The list reaches every file. The report shows the first 500 findings; on a large website not every large image appears there.
• No before/after table. The dialog states the count, the total size and the settings that apply, and then starts. That is deliberate: a preview would have to process every image in full, and the run itself would then do it a second time. With twenty large images the dialog would be minutes away.

If files are included that cannot be optimised — other file types, vector graphics, protected files — the dialog says so and leaves them untouched.

When an image appears as "too large to process"

Shrinking an image needs memory, and the more pixels it has the more it needs. How much may be used is set under Options → Optimisation → Working memory for image processing (default 128 MB).

What happens then depends on what is installed on the server:

• With ImageMagick the setting is only a question of speed. An image that does not fit is processed via the hard disk — slower, but it is processed. There is then no image size it fails at.
• Without ImageMagick it is a limit. Images that do not fit are skipped and shown as "too large to process". At 128 MB that limit sits at around 18 megapixels.

So there are two ways out: raise the value, or ask your host for ImageMagick. Which library was detected is shown under Options → Optimisation.

When an image stays unchanged

The confirmation dialog names, for every file, what has happened or will happen to it. If it stays unchanged, the reason is shown next to it — and for the cases that call for an action, the way out as well, as a tooltip on the state.

Shown as	What is behind it
No gain	The image is already well compressed; re-encoding it would bring nothing. It is left untouched and is not offered again until it changes.
Too large (memory)	See the section above.
Unsupported	The image library cannot read this file — usually a JPEG in the CMYK colour space from a print workflow.
Safelisted	The file is protected. It is deliberately left alone.
Changed on disk	The file has changed since the last scan. Run a scan, then try again.
No image library	This is not about the file: the server has neither ImageMagick nor GD, or the one selected under Options → Optimisation → Image engine is missing. No image can be optimised then, and the button is not offered at all.
Path rejected	The path recorded for this file is not a plain path below the site root. The file is left untouched.
Backup failed	The original could not be moved to the backup location. Usually that folder is not writable. Nothing was changed.
Could not be replaced	The optimised image could not be written back to its place. The original was restored.
Took too long	The server did not finish this image within the time set under Options → Optimisation → Time limit per image. This is about the server, not the image: an image that does not fit into the working memory allowed is processed from disk, and that takes many times longer. Allow more working memory, or more time. Nothing was changed.
Not recorded	The image was replaced but could not be recorded, so the original was put back. An image is never left optimised without its record.

For the last four the technical reason is in the site's log (see Large websites). After a run, the closing message also says how many files could not be optimised.

External optimisers

If specialised encoders are installed on the server, Media Organizer uses them for compression — that brings considerably more than the built-in libraries:

Format	Tools	Note
JPEG	jpegoptim	—
PNG	pngquant, oxipng, OptiPNG	pngquant is lossy (the biggest saving); oxipng and OptiPNG are lossless. Automatic prefers pngquant.
WebP	cwebp	When the source is already WebP.
GIF	gifsicle	Keeps animations.

Media Organizer downloads nothing and ships nothing along — it only uses what is already installed. If a tool is missing, it falls back to the built-in library automatically. Under Options → optimisation → available optimisers you see what was detected.

The image editor

You open the editor from the detail view via Edit.

Possible are:

• Cropping — freely or with a fixed ratio (1:1, 4:3, 3:2, 16:9, 9:16)
• Rotating and flipping
• Scaling to a maximum edge length
• Setting the quality
• Adjusting brightness, contrast and saturation

Here too the original is backed up beforehand; through the backups view you undo the edit.

Saving: two routes with different consequences

Route	What happens	References
Replace the original	Format and file name stay the same.	stay valid ✓
Save as WebP/AVIF	Creates a new file with a different file name. The original remains.	still point at the original — you have to switch them over manually

Where to go from here

• Automation: scheduled scans and 404 monitoring
• The command line

Applies to version 1.4.1.

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