Batch aspect ratio problem AP 256

[TomM1]

Batch processing tiff images to jpgs (horizontal and verticle). When I include a macro that changes 300 DPI to 72 Dpi, the aspect ratio is not preserved and the horizontal images get squished.

See the screen shot of settings.

 

 

[GarryP]

I don’t know much about the batch exporting functionality but if I was telling the software to export as 640x640 and my images are not ‘square’ then I would expect to get some ‘squishing’ somewhere along the line, even with Preserve Aspect Ratio switched on (I would be essentially overriding the ratio preservation).

Removing either the W or H value should get you what you want, I think.

[PaulEC]

As long as the "A" is ticked, it should set the longest side (H or W) to the setting you've chosen, and the other to the right size to maintain the correct aspect ratio.

However, AFAIK, the problem may be with the macro, which uses whatever image size you used when creating the macro. (There may be a way around this, but I don't use macros much myself.)

[GarryP]

I’ve just done a quick test using three images of different aspect ratios, and exported them at 300x300 and Preserve Ratio, and each came out with the same aspect ratio as they had before the export, as far as I can tell. (So my initial assumption was wrong, I think.)

So I think you might be right and the macro could be ‘messing with stuff’.

[TomM1]

There seems to be some issue with including a dpi change (without changing the pixel dimensions) in the macro. 

[TomM1]

So there must be a way to change the dpi in a batch process?

[David in Яuislip]

This has been an issue (AF-990) for yonks but a Bot post on November 26 claims that this has been fixed in beta 2.6.0.2900 and will be incorporated into the next customer release
Until then you can use exiftool eg
exiftool -Xresolution=96 -Yresolution=96 *.jpg

[TomM1]

36 minutes ago, David in Яuislip said:

This has been an issue (AF-990) for yonks but a Bot post on November 26 claims that this has been fixed in beta 2.6.0.2900 and will be incorporated into the next customer release
Until then you can use exiftool eg
exiftool -Xresolution=96 -Yresolution=96 *.jpg

Ok I will wait. Meanwhile I had to complete the project "manually".

[walt.farrell]

It is also possible to use one of the "change DPI" macros that have been provided in the Resources section and which were recorded in Affinity Photo 1.6, before the bug was introduced in 1.7. E.g.,  

 

[MLKIefer]

Here's something I found for reducing DPI in a batch job that is equivalent to reducing DPI (and only DPI) in the "Document-> Resize Document" function. I am at 2.6.0 on MacOS 15.3.1.

I have 24 MP images from a film scanner which I treat as archival photos. As I scanned them a few years ago, I rotated the portrait photos into the proper orientation so I have a mixture of untold thousands of landscape and portrait images. I convert these to 6 MP for editing and posting. The original photos are jpeg and I am saving them to jpeg in a different folder.

I simply did what was, I think, alluded to above. I do not use a macro within the batch job. I enter a math expression in the batch job's "Save as JPEG" "width" box to do this: "w/2" which then implicitly results in "h/2" for the height since aspect ratio is preserved. I've not used it extensively, but so far so good for what I need. I have not tested this with sets of images that have different MP counts. I gave myself a head-slap after figuring it out.

[Old Bruce]

28 minutes ago, MLKIefer said:

I gave myself a head-slap after figuring it out.

Have a kudos for posting a well thought out simple solution.

[MLKIefer]

Thanks - it was along the lines of finally figuring it out after 20 failures.