Inflated image size - quality/compression

Support
21

Ok great! So when 5004 is fixed it will address the large files when max-pixels is used (will you hard code quality or will it be an option/form setting?), but for the meantime the best option appears to be to remove max-pixels to prevent larger file sizes when they're not annotated

Tangent - is there any way to process all the existing images server side to ~75% quality (using Central as SaaS from getodk) to reduce space and speed transfer?

22

Hi @ahblake
in v2022.1.1 we added a fix for this issue (https://github.com/getodk/collect/issues/4978).
Now if you scale images down they should really have smaller size. Have you maybe tested it?

23

I will test this very soon, thanks!

Edit:

@Grzesiek2010, I tested on a samsung galaxy S10 running Collect 2022.1.1:

  1. Capture image, no max-pixels: 3856kb
  2. Choose image, no max-pixels: 3931kb
  3. Capture image, max-pixels=4000: 1835kb
  4. Capture image, max-pixels=4000: 1868kb
    Phone reports 'choose image' source as 3.84mb

Resaving (1) at 75% quality: 1609kb
Resaving (3) at 75% quality: 1700kb
Resaving (3) at 80% quality: 1841kb

So, as far as I can see:

  • Not using max-pixels will deliver the device camera output or selected image untouched
  • Using max-pixels=xxxx will return an image at approx 80% jpg quality
  • Ffor devices that don't allow setting camera quality, I should at a minimum use max-pixels=sensor resolution, or a lower value.

Going from ~6-8mb to ~1-2mb is fantastic, thanks for the fix!

24

Thanks a lot for reporting the issue with all those details. The bug existed for a long time but we weren't aware of it at all.

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