Problem with resizing of the images

[kempa007]

Hi all,

 

I decided to give a try to Affinity. It looks nice, but sadly I'm close to uninstall this program. It doesn't work as good as Photoshop. I don't now why it takes a good few secodns to load a simple photo (resolution of 5000 px) on ssd hard drive.

 

Second I have a problem with the same photo when resizng it. As I mention, orginal photo has an resolution of 5000 px. I wanted it to be resized to a size of 480 px. I don't know why, but the result photo has strange "pattern". I noted also that this "pattern" disapears when I reduce size of the image with steps ie: first reduce it to 4000 px, then 3000 px, 2000 px etc.

 

I tried to change resample method but nothing works...

 

Below I enclosed a reducend size of the image with this strange pattern visable around the eyes of the driver.

 

[SrPx]

Could it be that the default algorith, the one already there when you trigger the image change dialog (I mentioned this in some of my long walls of text here) for reducing images is set as nearest Neighbor? That's the fastest, but imo, not aceptable other than for some pixel art cases. I already said that I believe is better to set at least bicubic as default, or probably better, Lanczos, as I believe is a better algorithm.  So, the quality in reduction or amplifying (amplifying is not recommended, unless extremely necessary) would be, from worse to better: Nearest Neighbor, bilinear, bicubic, lanczos.

 

Dunno, sounds to me is the case here. Please do a test reducing it again using lanczos, you should see a perfect reduction.

[kempa007]

As I mentioned, I tried all resample methodes and every one produced the same output image. That is strage. I set lanczos and bicubic and didn't notice any differnce. I will try to enclose here more output photos with different resampling later.

[kempa007]

Hi,

 

I enclose photos reisized with different resampling method. I don't know why, but bilinear didnt work last time. This time produced a good photo and it is only resampling method that works good. Results with the rest methords you can see in attached photos.

 

It is intresting that bilinear methode produced also the smallest file in kB.

[kempa007]

the next question is what is the fastest way to get an effect simmilar to "save for the web" from Photoshop or even better IR_fanview. I try to export jpg with the sam quailty of 80% but irfan_view producing file of 30 kB, and Affinity producing of 43 kB. That's a huge different. When I change the qulity of the jpg file in a way that file is 30 kB in Affinity there is huge different in a quality of output image... Affinity must be set to about 70 % of the quality.

 

And there is no live preview of changes of the quality during export. That should also be fixed.