pngs and jpegs not exporting clearly to PDF

Forum|Forum|1 year ago
April 1, 2025
5 replies
1272 views

Hello,

I am working on a document that I've edited numerous times. I drop in a new png or jpeg of a QR code (tried both). The files is crystal clear in indesign, but when exporting to PDF, the QR code (no other images) is fuzzy or has a small grey outline round it. I tried creating a brand new document and using the same QR code and it exported fine. I assumed then that the document was corrupt, rebuilt it and started again, but to the same issue. Is it a size thing? As it's a QR code? Surely not, .id can handle tiny, intricate graphics. I've set the QR at over 1cm, the recommended minimum size for QRs. I'm completely stumped!

Thanks

Kim

L

Laubender

Community Expert

Hi @Steve5FD8 ,

in case you are using pixel-based images for an QR code it's not so much important if the files are high-res or not.

In an extreme case every square in an QR code could be exactly one pixel wide. There would be no loss of quality with exporting to PDF if the right image type is used and the export will not try to re-render the placed images.

For example:

Save the QR codes as 1-Bit bitmap data in PhotoShop as TIFF file, place that in InDesign.

When exporting to PDF make sure you do not downsample bitmap data.

Download a sample from my Dropbox account:

https://www.dropbox.com/scl/fi/f4cltq0hx70nkb4yzujsa/QRCode-Vector-vs-PixelImage.zip?rlkey=j9j3tp5009teh8l8umztqbwv3&dl=1

QRCodeVector-vs-PixelImage.indd

On page 1 is the QR code generated in InDesign as vector graphic.

Page 2 is showing a placed lowres TIFF image of the same code where every square of the QR code is just 1 pixel wide.

All in all the whole QR code image is 25 x 25 pixels. Effective resolution in InDesign is about 8 ppi.

I exported the InDesign document to PDF where I disabled downsampling for 1-bit images.

From my German InDesign showing page 2 where the bitmap is placed:

Regards,
Uwe Laubender
( Adobe Community Expert )

Dave Creamer of IDEAS

Community Expert

QR codes are typically black-and-white rectangles. Ideally, they should be created in InDesign or a vecter program such as Illustrator.

PNG and JPEG are raster (pixel) formats and are not appropriate for this type of image. JPEG is the worst format for flat-color graphics and PNG is only RGB or grayscale.

If they must be raster images, this is how you should process them:

Create them at 1200 ppi if possible, but if you can't make them as high as you can.
In Photoshop, open the code and convert to Bitmap mode (if they are in RGB, you will have to convert to Grayscale mode first, then Bitmap.)
Use the 50% Threshold conversion setting. (You can adjust the resolution to 1200 ppi here if you wish.)
Save as TIFF, using the LZW compression setting.

Place in InDesign. The white background will become transparent and you can color the QR code in InDesign if required. These images will not be processed as color or grayscale images and stay crisp.

David Creamer: Community Expert (ACI and ACE 1995-2023)

S

Steve5FD8Author

Participant

Thanks Dave. We use a website to generate our QRs, available in png, jpeg, SVS, EPS and PDF. Which is best to pick up?

Thanks

Kim

Dave Creamer of IDEAS

Community Expert

It's possible the SVG, EPS, and PDF are vector. Open them in Illustrator and check. If they are, use the PDF (you may want to crop the page size in Acrobat if necessary).

If all the formats are raster, make it the highest resolution possible. Export out the PNG and PDF, then open in Photohshop. If the PDF is an RGB image, you might was well use the PNG for ease of use. The convert and save as TIFF as I posted earlier.

Edit: If you use the QR codes in different colors, I like to convert the vector art to high-resoluton, LZW-compressed TIFF by exporting it from Illustrator. That way, I can color it in InDesign. A high-res Bitmap-mode TIFF file will look like vector art when printed.

David Creamer: Community Expert (ACI and ACE 1995-2023)

chantalb84891737

Participating Frequently

Same issue here. It's only with jpg files, when it's eps I have no problem. It is since I've updated Adobe into the newest version. I can't solve this problem eather.