Query on jpeg upload pixel dimensions limit

[Bill Landenberger]

Just a quick query on the pixel dimensions limit for jpeg uploads.  I was surprised to read in one of the facebook groups that the limit on the 360cities site stated "JPEG files can have up to 30000×15000 resolution (which is the maximum size allowed by JPEG format)" - which is a quote take directly from the 360cities website.  I thought this odd, since the size limit for jpeg format is 65,535×65,535. I've never tried before to upload a jpeg bigger than 30,000×15,000 (450MP) before, but just ran a test and uploaded a 40770×20385 (~831MP) jpeg with no problems, and it wasn't downsampled after upload either.  Could we please have a clarification/correction of what the actual limit is?  I am guessing anything up to 65,535 in any dimension is possible - so for a 360×180 pano, that would be  65,534×32767 (~2147MP).
cheers,
Bill

[Erik Krause]

Am 21.12.2024 um 03:19 schrieb Bill Landenberger:

> Could we please have a clarification/correction of what the actual
> limit is? I am guessing anything up to 65,535 in any dimension is
> possible - so for a 360×180 pano, that would be 65,534×32767
> (~2147MP).

I would also like to know why there is a pixel limit for TIFFs? The file
format doesn't have one, only a file size limit at 2GB. And this is
avoided by BigTIFF, which is supported by krpano.

--
Erik Krause
http://www.erik-krause.de

[Elena Martinez]

Hello Bill and Erik,

Thanks for your messages.

Bill, can you let me know where did you get the info about the jpg size limit?

We don’t know the exact limit (jpg or tiff), as it depends on multiple factors, not just resolution. We certainly support more than 30k panoramas, there are larger files published on 360Cities.

Regarding BigTIFF, we haven't tested it yet. We need to work on it and I'll let you know. Erik, if you'd like to share a BigTIFF with me for testing purposes, please let me know.

Best regards,

Elena

[Bill Landenberger]

Thanks for your response Elena.  The bit about the 30k limit for jpegs (and the 65k limit for tiff) is just underneath the "JPEG or TIFF" heading on the 'uploaded panorama requirements' page:
https://www.360cities.net/help/uploaded-panorama-requirements
cheers,
Bill

[Elena Martinez]

Hello,

We've been testing, and it seems that information is outdated. We'll update it as soon as possible.  

We still need to do further testing to determine the maximum values, as they depend not only in resolution. If you could share your findings with us, we would appreciate it.  

And happy new year!

Regards,

Elena

[Bill Landenberger]

G'day Elena,

I just ran another test.  I exported a 65500×32750 (2145MP) image from PTGui, which was the largest panorama that PTGui will allow for a jpeg 360 pano.  The file size was 399MB.  It uploaded fine, although it took a while on my slow connection.  It also took about two hours to process once uploaded, so it was stuck on 'pending' for a while - obviously giving the server a hard time!  But it eventually completed, and wasn't downsampled at all.  I haven't published it, but you I am assuming admins can view it.  I called it 'Test 65k'.  I can publish it if needs be, otherwise I will delete it.
p.s. and a happy New Year to you too!
cheers
Bill

[Elena Martinez]

Hello Bill,

Thanks a lot for the information. 

When you have a chance, please share its url with me. I'll be able to check it even if it's unpublished.

Thanks a lot!

Elena

[Bill Landenberger]

Elena, would you believe I just deleted it yesterday!   But I have re-uploaded.  Seemed to process a bit faster this time:
https://www.360cities.net/image/test-65k
Note that at that resolution, the image is interpolated.  The 'native' resolution version is only 20656×10328 (https://www.360cities.net/image/yapang-sculpture-garden)
cheers,
Bill

[Bill Landenberger]

Elena, could you please advise if still need access to my 'test-65k' panorama?  If not, I will delete it.
cheers, Bill

[Elena Martinez]

Hi Bill,

Yes, you can delete it. Thanks a lot!