[AP] Document file size grows progressively with each save without adding new information

[Alex_M]

I've noticed that Affinity Photo documents grow progressively in file size after each change in the document without adding new information in it like layers, masks, shapes, effects etc. For example, if I delete some layer, undo, and then save, the document grows in file size. No matter how many times I repeat this, it grows more and more. I don't have "Save History With Document" enabled.

The document I am working on right now has grown to 132 mb. I copied and pasted all its contents into a new document with the same dimensions and then saved it and now the new document is more than 3 times smaller at 41 mb.

What causes this and how can I avoid it? Thanks in advance!

Edited October 28, 2019 by Alex_M
An image attachment was broken.

[Claudio60]

Is the document you're working with a jpeg file?

 

[Greyfox]

3 hours ago, Claudio60 said:

Is the document you're working with a jpeg file?

I assumed that @Alex_M was referring to a .afphoto project file, however I can't get the progressive size increase to happen here.

 

[Claudio60]

12 hours ago, Greyfox said:

I assumed that @Alex_M was referring to a .afphoto project file, however I can't get the progressive size increase to happen here.

 

You're right Greyfox, I've put it badly, I wanted to know if the initial/original image in the .aphoto project was a jpeg file or not. Anyway you can take a look here:

 

[Mark Ingram]

It should get smaller if you do "Save As" as well. This is intentional behaviour. You should find at some point, your continual saves will result in a smaller file once again.

[Alex_M]

2 hours ago, Mark Ingram said:

It should get smaller if you do "Save As" as well.

I tried this, but they get only a bit smaller. The example file above goes from 132 mb to 100 mb when saved with "Save As" which is still much larger than the version where I copied the contents from the old document into a new one (41 mb).

2 hours ago, Mark Ingram said:

This is intentional behaviour. You should find at some point, your continual saves will result in a smaller file once again.

When exactly is this point? I tried saving the file at least 10 times without adding new layer information and it still grows in size. What's the idea and reason behind this?

19 hours ago, Claudio60 said:

Is the document you're working with a jpeg file?

 

The document is an afphoto file, not a JPEG. Please refer to the last attached image in my original post.

[Greyfox]

3 hours ago, Claudio60 said:

I wanted to know if the initial/original image in the .aphoto project was a jpeg file or not.

Thanks for the link @Claudio60

When I did my tests, the image in the .aphoto project was a jpeg, but I was using save as (with a difference in file name) each time so I could compare, and the file size wasn't changing. I now realize it's the save back to the same file that brings about the growth in file size, and it does happen here too.

2 hours ago, Mark Ingram said:

It should get smaller if you do "Save As" as well. This is intentional behaviour. You should find at some point, your continual saves will result in a smaller file once again.

Intentional - Does that mean it's actually been programmed to do that deliberately? I wonder why.

 

[Claudio60]

2 hours ago, Alex_M said:

 

The document is an afphoto file, not a JPEG. Please refer to the last attached image in my original post.

I saw that your attachement is an .aphoto file but what  is the file extention that's inside the aphoto project file: jpeg, raw, tiff?

[Mark Ingram]

2 hours ago, Alex_M said:

When exactly is this point? I tried saving the file at least 10 times without adding new layer information and it still grows in size. What's the idea and reason behind this?

It's for (Save) performance. There should be a point at which the file gets smaller with continuous saves, I'm not sure what that trigger point is, I'd have to check the details of the algorithm. 

[Claudio60]

1 hour ago, Greyfox said:

Thanks for the link @Claudio60

When I did my tests, the image in the .aphoto project was a jpeg, but I was using save as (with a difference in file name) each time so I could compare, and the file size wasn't changing. I now realize it's the save back to the same file that brings about the growth in file size, and it does happen here too.

Thanks Greyfox

[Alex_M]

1 hour ago, Claudio60 said:

I saw that your attachement is an .aphoto file but what  is the file extention that's inside the aphoto project file: jpeg, raw, tiff?

If you're asking about the contents of the document, it's just regular pixel layers created in 3D software as 8-bit images. The document's bit depth is also 8-bit and the color space is sRGB. Oh, and there's one live denoise layer which shouldn't add anything to the size AFAIK.

1 hour ago, Mark Ingram said:

It's for (Save) performance. There should be a point at which the file gets smaller with continuous saves, I'm not sure what that trigger point is, I'd have to check the details of the algorithm. 

I see. Thanks for clarifying. In this case would it be nice if there was an option that clears the save cache or whatever it's called so that I can save a "clean" document once I'm done with it to save on HDD resources. I wouldn't mind the extra few seconds that I'll have to wait if my document gets 3 times smaller in file size. Maybe I will make a suggestion in the appropriate section of the forums. Manually copying the contents of a document into another one is clunky when it could be easily automated by the program.

[Claudio60]

20 minutes ago, Alex_M said:

If you're asking about the contents of the document, it's just regular pixel layers created in 3D software as 8-bit images. The document's bit depth is also 8-bit and the color space is sRGB. Oh, and there's one live denoise layer which shouldn't add anything to the size AFAIK.

Tks for the clarification

[Mark Ingram]

5 hours ago, Alex_M said:

I see. Thanks for clarifying. In this case would it be nice if there was an option that clears the save cache or whatever it's called so that I can save a "clean" document once I'm done with it to save on HDD resources.

Save As normally performs this function. 

[powerupmedia]

On 10/28/2019 at 10:50 PM, Mark Ingram said:

Save As normally performs this function. 

But only when actually writing to another file. Overriding the same file won't work.
The easiest method at the moment I found is to delete the file (while still open in Affinity) and save once more.

I get why this functionality is the way it is, but something like a "Save and compact" would be VERY welcome since backing up these files can become very space consuming over time.

At the moment I'm working on a file hovering between ~19Mb and ~26Mb which is a 36% file increase