possibility to exclude one special pixel image from the export compression/downsampling process?

Quick clarification on the trick: the “for images above” threshold protects images whose effective ppi is *below* the cutoff — it only works when your special image has the lowest effective ppi of the bunch. If it's the one with the highest ppi, no threshold setting can exclude just that one, since everything above the cutoff gets downsampled. In that case the honest options are exporting with “Do Not Downsample”, or downsampling the smaller images separately first (e.g. in Photoshop), so the PDF export can run with downsampling off.

Also, is the final output for print or screen? If it’s for print why not turn off down sampling (Compression>Do Not Downsample)? A modern RIP shouldn’t have any problem with high resolutions.

Hi ​@ROBGAU , Can you share the image?

thanks for your help corcton,

that does not work i think … 

if i screw up the export size value “for images above...” to a value over the effective pixels of my really fat image….ALL !! other images that are smaller than this.. are also not downsampled and keep their real size.

that is not what i wanted...i want all smaller to be resized...only one NOT.

it i misunderstood what the trick should be please correct me.

Hi Tommes — there's no per-object "exclude from downsampling" switch in InDesign; the Compression settings in the Export Adobe PDF dialog apply to the whole document.

But there's a clean workaround that does exactly what you want: InDesign only downsamples images whose effective resolution is above the "for images above [X] ppi" threshold. So check your special image's effective PPI in the Links panel, then in Export Adobe PDF > Compression set the threshold above that value — e.g. "Bicubic Downsampling to 300 ppi for images above 450 ppi". Your special image then keeps its full resolution while everything else gets downsampled.

One caveat: the JPEG compression quality setting is still document-wide, so the image will still be JPEG-compressed (just not downsampled). If you need it truly untouched, you'd have to switch the Compression to ZIP (lossless) for all images — at the cost of file size.

Reference: https://helpx.adobe.com/indesign/desktop/save-export-and-publish/save-and-export/adobe-pdf-export-options.html (Compression section)