NEW Topaz upsampling product: A.I. Gigapixel

[digitaldog]

Hi Andrew,

We don't know the inner workings but, in general, resampling at linear gamma has benefits for color fidelity, smoothness of gradients, and can reduce halo artifacts. So sooner or later, there are bound to be interim gamma changes, and a final mapping of the result to the required colorspace.

Cheers,
Bart

Good point! I know ACR/LR do the same but honors a rendered images color space. I don't think PS does however. I was wondering if this product might be converting to Lab like the old recommendations to do so in the past but you're right, we'll never really know.

[Doug Gray]

Good point! I know ACR/LR do the same but honors a rendered images color space. I don't think PS does however. I was wondering if this product might be converting to Lab like the old recommendations to do so in the past but you're right, we'll never really know.

Photoshop definitely does not resample using gamma=1 and you can get some problematic aliasing (moire) if you have close, regular patterns, like striped shirts/picket fences in the image. When that occurs I switch to gamma=1 then resample and switch back.

[kirkt]

Strange thing that I think is occurring, and experimental users please confirm this - when you pass a tagged,non-sRGB image to AIGP and use the "Match Input (faster)" color profile option, what appears to happen is that the file remains in the input color space but gets tagged with an sRGB tag upon output.  When you open the file in PS, the document color space is indicated as sRGB but the color is, predictably, undersaturated.  Assigning the original profile corrects the problem.

In other words, the current version as a little hiccup in terms of tagging the output.

kirk

[kirkt]

I have also noticed that AIGP is doing noise reduction and some slight sharpening, presumably using the AI Clear algorithms in conjunction with the scaling of the AIGP network.

kirk

[fdisilvestro]

Photoshop definitely does not resample using gamma=1 and you can get some problematic aliasing (moire) if you have close, regular patterns, like striped shirts/picket fences in the image. When that occurs I switch to gamma=1 then resample and switch back.

Could you share how you do it? Do you have a icc profile with gamma=1 or change mode to 32 bits?

Thanks

[Wolfman]

I have tried it and it does a good job from what I have seen so far. If you are pressed for time and want a quick workflow this isn't for you working on large original files....it is very slow. I have other ways to enlarge that are much faster and I would say as good quality wise.

[digitaldog]

Could you share how you do it? Do you have a icc profile with gamma=1 or change mode to 32 bits?

You could create such a profile using just Photoshop if so desired. Select the RGB working space you want in Color Settings. Select Custom RGB... from the same menu, alter the Gamma, close and save the profile. Now SHOULD you do this?   

[Doug Gray]

You could create such a profile using just Photoshop if so desired. Select the RGB working space you want in Color Settings. Select Custom RGB... from the same menu, alter the Gamma, close and save the profile. Now SHOULD you do this? 

Yup, that works. But be sure to use 16 bit RGB first. 8 bits will royally hose the image in linear gamma.

I've not seen the problem often. Most frequent occurrence is when printing a high rez image from modern DLSRs with a printer when the DPI doesn't match and the printer driver downsamples or when the image is downsized to the printer's native DPI.  Then, downsampling to printer native DPI in linear gamma fixes the printer aliasing. It's really not often a problem which also means when it comes up people have a hard time figuring the cause and confuse the moire in the print with intrinsic capture moire which is more common. Especially with cameras that don't have anti-aliasing filters. Once it's in the image it's a pain to remove or mask.

[fdisilvestro]

Thanks Andrew, Doug

I was wondering if that was the recommended way.

[Doug Gray]

BTW, linear gamma is best for fixing moire that is induced by downsampling. Upsampling routines don't have the problem and the better ones, like the topic of this thread, shouldn't change gamma. There are some fairly sophisticated upsampling algorithms that do things like look for edges and enhance them and they work best in normal gamma colorspaces. They are already aware, and compensate for, gamma. Linear gamma is best for linear transform operations which are typical of downsampling where the higher spatial freqs are cut and the algorithms are not gamma aware such as Photoshop's.

[Hening Bettermann]

Here my first experience with Topaz AI Gigapixel:

My Mac: Mac Pro Early 2009, 2.66 GHz Quad-Core Intel Xeon, 24 GB RAM, Graphic Card NVIDIA GeForce GT 120, 512 MB. Mac OS 10.11.6.
AI Gigapixel version 1.0.1
The image I tried to test was a Canon 5D2 file ( ca 20 MP) with a little cropping.

Under Enlarge Options, ppi, I can enter a max of 300 ppi, not 360. So this would require additional re-scaling later, since I want 360ppi.

During the processing, the image size in pixels is displayed by the application as original 3454x5611, after upscaling (to 126 cm in height) 23 268 x 37 800.
After upscaling in Iridient, where I can enter the intended size in mm, the final size ist 10 993 x 17 868 px, as displayed by the Mac Finders Get Info. --??

During the processing, all sorts of weird things happen in the Finder, when I tried to move the application window or minimize it or do anything else at all. Amongst  others, the Dock did not pop up any more. Every movement of the app window was extremely unsmooth, if at all possible. It seemed extremely delayed so that it was all unpredictable. Small dots (1 and 2 pixels?) appeared in the app window, in the Finder window and in the menu bar. (Fortunately, they disappeared after restart of the Mac.) During one period, the mouse pointer was grossly enlarged. The Time Machine menu was displayed (something I had not asked for), and it took a while and some other Finder clicks, not sure which, before it disappeared again.

After about 18 minutes, I decided to quit. I had to force quit, which was possible with some hassle, I think due to the unpredictable delay of actions after mouse click.

So the Mac version needs some de-bugging before I can test it any further.

[Wayne Fox]

My Mac: Mac Pro Early 2009, 2.66 GHz Quad-Core Intel Xeon, 24 GB RAM, Graphic Card NVIDIA GeForce GT 120, 512 MB. Mac OS 10.11.6.

from Topaz ...
All NVIDIA cards with <1GB of dedicated VRAM are unsupported

Might explain some of your problems.

[Wayne Fox]

on screen stuff hard to really tell when it comes to output.  This file is from an IQ180, and has been uprezzed to produce a 74x37 inch print at 360 dpi.  I have printed this image up to 84” directly from LR with excellent results (using Lightroom standard output sharpening).  Upper left is output from LR print module to jpg, sharpening set to standard/glossy.  Top right is using Topaz AI Gigapixel, bottom right is Photoshop preserve details 2 with 30% noise reduction followed by Focus Magic at 7.  Bottom right is PS Preserve details 2 no noise reduction or sharpening. I added a small version of the full file to help with context of what the image is.

Took 20 minutes with 2018 MacBook Pro 2.9ghz/32gigs ram and eGPU Radeon RX Vega 56 8176 MB.

I’m going to print a strip from all 4 files to see if there is much visible difference.  Not sure there will be.

[Hening Bettermann]

Oops! thanks for your alert, Wayne. I would have liked to compare AI to Iridient, which I find superior in upscaling and sharpening to Photozoom Pro, which otherwise has received much praise by Bart. But before I buy into a new graphics card...

[Bart_van_der_Wolf]

Oops! thanks for your alert, Wayne. I would have liked to compare AI to Iridient, which I find superior in upscaling and sharpening to Photozoom Pro, which otherwise has received much praise by Bart. But before I buy into a new graphics card...

Hi Hening,

I feel your pain, my graphics card is also not supported (although it has plenty of memory). Sometimes it works, but most of the time it crashes/closes without producing a result. Given their compatibility information (here), it is unlikely they will add support for my card at a later date.

So, a hardware upgrade has gotten a higher priority (amongst other priorities).

Cheers,
Bart

[Hening Bettermann]

Hi Bart,

if you upgrade your hardware before I do (which sounds likely ;-) ), please consider comparing to Iridient, which is now Windows-too :-)

Good light!

[vjbelle]

I also used an 80mp file that I have and resized it to 74 inches with A.I.  With my recent Windows build the process took 30 minutes (Wayne advantage the eGPU).  Topaz utilizing the GPU for a lot of work would require me to upgrade my GPU to meet or beat Wayne's times.  The result is more what I have seen so far.  When compared to Adobe 'Preserve Details 2.0' it is initially, maybe, a little sharper because Topaz uses some sharpening.  Image darkening is an issue which has been previously mentioned.  But I think that the Adobe approach is much more preferred for me because of the overall final appearance of the file. The final output is little smoother and just as sharp (with a little tweak) with the same amount of detail preservation without an artificial look - and takes significantly less time. 

Adobe deserves a lot of credit for their efforts in this direction.

Victor

[Paul2660]

One thing is for sure, I had totally missed the "preserve Details 2" uprez in CC 2018.  Thanks to Victor and Wayne for bringing it up. 

No doubt that it's much better than previous versions and IMO is for what I do noticeably better than the Topaz output.  Topaz may win in a 600 % uprez, but I just don't need that much as I am starting with 42 to 50MP. 

Paul C

[plugsnpixels]

An update is available:

Update V1.0.2 has the following changes:

New Features:
    - none

Bug Fixes:
    - Custom ratios did not work correctly
    - Start button was not enabled when size was measured in inches
    - Installer would stall after user accepted terms and conditions
    - Saved as 72ppi instead of original resolution
    - Underexposure of processed images has been improved


GUI Modifications:
    - none

[vjbelle]

The update has dramatically improved the image darkening issue.  Speed also seems to have improved.  I took a GFX file and upsized it to 40 inches at 600dpi which took 20 minutes.  Compared to Adobe Preserve Details 2.0 I would say that Topaz has the edge.  It's not a sharpening issue any longer but an overall look.  Topaz has a smoother appearance.  Upsizing to 600dpi would eliminate the Canon software upsizing which is incorporated into the Canon Plugin.

Victor