Jump to content
Brad Brighton

[By Design] PNG pixel count restriction on export?

Recommended Posts

I feel a bit silly bringing this one up since you guys are the experts,...

I'm trying to export a recent panorama with 1.6.11 and get this error (screenshot attached) due to the pixel count on the major axis being > 32767. (I checked with the beta version 1.7.0.112 as well; the warning message is still there but it *is* readable vs the 1.6.x version.) I've never run into this before so I wanted to learn more -- and everything I can find about the dimensions spec says width and height in the PNG format are each 4 bytes, not 2. NOTE I'm clear that I'm not talking about bit-depth per pixel; this is about the overall pixel dimensions of the exported image.

I assume I'm missing (or misunderstanding) something somewhere. Would you be kind enough to set me straight (hopefully with references) or if somehow I have it right, please file a bug?

Screen Shot 2019-03-24 at 8.17.58 PM.png


https://bmb.photos | https://vocallength.com | https://khonsuapp.com Focus: The unexpected, the abstract, the extreme on screen, paper, & other physical outputTools: macOS (Primary: Mojave, MBP2018), Canon (Primary: 5D3), iPhone (Primary: X), Epson

Share this post


Link to post
Share on other sites
2 minutes ago, v_kyr said:

Many thanks for the link, v_kyr. My pre-post search didn't find that.

Ugh -- my PNG workflow (macOS) hamstrung by outdated Windows APIs? Gotta love it...


https://bmb.photos | https://vocallength.com | https://khonsuapp.com Focus: The unexpected, the abstract, the extreme on screen, paper, & other physical outputTools: macOS (Primary: Mojave, MBP2018), Canon (Primary: 5D3), iPhone (Primary: X), Epson

Share this post


Link to post
Share on other sites
27 minutes ago, Brad Brighton said:

Many thanks for the link, v_kyr. My pre-post search didn't find that.

Ugh -- my PNG workflow (macOS) hamstrung by outdated Windows APIs? Gotta love it...

The .NET framework is the cause for this limit, which only allows for a maximum object size of 2Gb . Windows itself can handle larger PNG files just fine without issues; it's just that Affinity for Windows is built with .NET framework, and "inherits" this limitation.

For example, I can export a 33.000 x 33.000 large image to PNG in PhotoLine. I can open this in IfranView for viewing. ImageMagick works fine too with these images.

Attempting to load a 33.000x33.000 PNG image in Affinity crashes it, probably due to that .NET 2GB heap size limitation.

Anyway, most image editors will put a limit on max canvas size as well: Affinity can handle up to 256000x256000 pixels, while Photoshop goes a bit higher by supporting 300000x300000 pixels. PhotoLine doesn't seem to have a limit, and will happily output a million pixels (which does seem to become problematic for Windows at that point to generate a thumbnail, and Irfanview refuses to open that file).

I've worked with very large images for academic purposes in the past, and Photoshop's max px dimensions were causing us headaches at the time. I am actually a little surprised to discover today that Affinity Photo's dimensions 'only' goes up to a 256000 px size: I would have expected more. But it is of course more than enough for 99.9% of users.

Share this post


Link to post
Share on other sites

Thanks for the additional context, MOB. I've only just now hit this limit so it's annoying but definitely not the end of the world. It is also a bit disgruntling to be constrained by the limitations of a platform I actively avoid whenever possible. What are you going to do though?  ¯\_(ツ)_/¯


https://bmb.photos | https://vocallength.com | https://khonsuapp.com Focus: The unexpected, the abstract, the extreme on screen, paper, & other physical outputTools: macOS (Primary: Mojave, MBP2018), Canon (Primary: 5D3), iPhone (Primary: X), Epson

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

×
×
  • Create New...

Important Information

Please note the Annual Company Closure section in the Terms of Use. These are the Terms of Use you will be asked to agree to if you join the forum. | Privacy Policy | Guidelines | We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.