Original picture size vs synced picture size

Hey all. I am using Seafile for a while and very pleased with it. But i have a question regarding picture sizes.

I am using Iphone and take a picture. If i check this picture size it is (for example) 8MB and if i use Wireless transfer app to download it to my computer it will also have 8MB. But once this picture is synced to Seafile, the size is 1,7MB.

I must admit i cannot see any visual difference between pictures by eye, but would still wish to know the magic behind this. And is it possible to set up Seafile to keep the “original” file.

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Seafile does not modify pictures. Does the picture size really change when you login on Seahub and download the picture?

I don’t know. Maybe the conversion is made by the iphone - so that the file size is smaller for upload. In any case i have this output:

  • picture size on iphone is for example 8MB (actual size). I checked this by sending email with a picture to myself
  • i can use Wireless transfer app to download the image. The size will also be 8MB
  • i start Seafile client and it will report that image is uploaded to server
  • i check the size of picture on Seafile server https page - reports 1,7MB
  • i have Seafile client sync made on my computer - after the image is synced with the server it also has a size of 1,7MB

I cannot find any setting on the iphone that would allow me to change this behaviour, so the question here is if this setting is somehow hidden in the Seafile server (or client on Iphone) and can be changed?

PS: ah maybe also other info that would help.
Server is running on Raspberry Pi 3 - latest version 6.0.9
Iphone is 4s, running latest client.

Can you go to Seahub and download the file using your browser to check the size again?

In my opinion this should not happen. If it really somehow compresses the photos it’s a bug.

Does the picture have any “special features” like HDR or the new iOS “live” video-snip?
Maybe there is a difference in how these are handled.

Ok here is some testing i have done. I am usually using Camera+ application for taking pictures. The app has different settings for quality. I have set it to High Quality JPEG all the time. But for the test i have tried other settings as well.
Camera+ app
Downscaled JPEG - Original size 572,7kB → Seafile size 566,9kB
Normal JPEG - Original size 1,7MB → Seafile size 1,4MB
High JPEG - Original size 7,6MB → Seafile size 1,8MB
Losless TIF - Original size 12,1MB → Seafile size 12,1MB

Camera (inbuild Iphone app)
Original size 1,5MB → Seafile size 1,3MB

So… TIF, which is the format that Seafile cannot display (preview) is the only one with the “correct” size.

As far as i know there is no HDR or anything special regarding the pictures, but anyway i have done a sample with “Normal JPEG quality” if anyone can see something that would cause the difference.
Original file -

Because i can only upload 1 image i had to make a second post:
Image that was uploaded and then downloaded from Seafile

That’s interesting, I always thought the auto upload feature saves my photos with original file size.
Did the test too, you are right: the file size of the picture which is uploaded through Seafile is a bit smaller. Not a big difference in my case: Original size 2,2 MB, Seafile auto upload: 2 MB.

Btw: I also use an iPhone 4s

It may be due the difference between MB and MiB. Seafile’s web interface uses MB (1000x1000).

Maybe the people affected can compare the checksums of the related files to clear up this issue.

Thought that as well in the first place, but the difference is too big here and the two images uploaded above to have quite different file sizes.

The file size is definitely different:

Left: Picture uploaded through Seafile camera auto upload, right hand side: original picture size

In my opinion you have to lose the metadata of the image during the transfer into seafile.
Do you have metadata of the image before uploading?
Is that what you always have after downloading the image from seafile?
I have done a test with my android device, the pictures have exactly the same size, and the metadata are kept

To me it looks like the iOS app does some shit with the images.

@daniel.pan this looks like a serious issue needing a quick fix.

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Maybe it is indeed the loss of the metadata:

Any workaround for this issue yet? I would still like to have “original” file as it is for backup. Now i have to copy pictures manually from Iphone if i want to keep them.

If you use the webinterface it should work (as a workaround).

@daniel.pan @Jonathan Please give us some news on this.

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This is because in old version of iOS, app can’t read system photos directly. It has to call API to get access to photos. Different parameters to the API will return a slight different photos. In the latest version of iOS, the original photo can be accessed directly, but we haven’t changed the code yet.

OK thank you for the explanation, so can we expect to see an update soon?

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