IMAGE CONVERT not recompressing JPEGs?

Why doesn't it work, when i remove the "write to destination" check box, replacing the JPGs inplace? I would like to convert images to 85% for OneDrive, without extra folders to write to. I think i can remember, that some Image Convert stuff was fixed recently, but forgot what it was. When i use the function now, i see Opus converting something, but i have no idea, if it is actually written to some location. But i see the progress bar. Strange. :thinking:

We aren't aware of any problems in that area. If you're seeing it fail, please tell us how to reproduce the problem and we'll take a look.

Basically i select JPGs, & try to convert them using these settings.

What do you expect it to do in that case?

If the image is already JPEG and you don't change any other aspect of it, specifying "convert to JPEG" will not do anything at all.

By default, the image converter avoids re-compressing JPEGs if nothing else is changing (e.g. not resizing).

You can add the NOLOSSLESS argument to the command to force it to always recompress JPEGs if your aim is to recompress them to a smaller size/quality.

I've edited the subject to be a bit more descriptive, assuming this is what we are talking about. The original subject and posts don't say much more than "it doesn't work", so we're having to guess a bit here.

The same, as if i would write them to the destination, a smaller version of the JPG, say, from 8MB size to 2MP. But "in place".

Yeah, sorry, it wasn't so clear. I just want to make the size smaller, accepting a little quality loss. I will experiment wit the NOLOSSLESS argument a bit. Thanks Jon & Leo!

I added a shift-click command to the regular "Convert Image" context menu, which adds the NOLOSSLESS switch. Works ok, but always requires you to think ahead of what exactly you want to do. Sometimes I don't think hard enough and end up with no converted images. Then I think again and restart using the shift key.

I guess there are others who run into this. Maybe the "Rotate [..]" dropdown area could take another checkbox to toggle between lossy and lossless rotation. This could clear up how the dialog works in these cases. The jpg quality setting could work independently from that point on and not rely on saving the images in destination (given the nolossless switch does not have any other effect I currently don't see of course o).


@tbone @Leo @Jon

I want to do exactly the same: Batch recompress a large number of JPG files such that their size is reduced e.g. to 25% (i.e. lossy recompression). My phone takes pictures that are 4-5 MB each, but I want to use them on the web i.e. they must be smaller.

Ideally I would like to do it with a right-click menu button like @tbone showed.

Could you briefly show me how to add this button in my DOpus?

Thanks a lot - your help is highly appreciated.


That will overwrite the files without prompting. Remove REPLACE if you want to be prompted first.

Remove HERE if you want the original files to be left alone, and the new files to be put in the destination folder instead.

Change the QUALITY value as desired. It's out of 100. You can often set it quite high, e.g. 95, and still reduce file size by a lot from what comes out of a camera.

For how to use the command on a toolbar: How to use buttons and scripts from this forum.

To use the command in a context menu:

  • Settings > File Types

  • Double-click File Type Groups > Images (or find the JPG type if you only want it on that type of file).

  • On the Context Menu tab, add the command there.

    (Exact dialog depends on if you're editing the group or the individual type. If there's a Type drop-down in the dialog, choose Run an Opus function. The Function drop-down will always be there and should be left as Standard Function (Opus or external).)

Image command docs if you need something slightly different.

Thanks a lot for the very quick and precise answer. Your support is awesome!

It works like a charm now!

I created a few buttons with different Quality "numbers" for different purposes - very convenient!

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