How to trigger new resizing algorithm without reuploading?

jfriend

I've read about the new-improved downsizing algorithm for smaller versions of our images that makes it less likely to see JPEG artifacts. I'm wondering if there's an easy way to take an existing image and cause new smaller sizes to be generated. I know I could reupload, but I'd rather not do that. Is there some change that can be made to the image that will trigger the remaking of the smaller sizes using the new algorithm?

Here's one I'd like to apply it to (see artifacts at the mountain/sky boundary):

Andy

I tried "make second copy" in your gallery. Any difference? You could also do an upload-new - and put it here

Nope - no difference

rainforest1155

Andy wrote:

I tried "make second copy" in your gallery. Any difference? You could also do an upload-new - and put it here

That doesn't seem to trigger a recode - it's a 100% identical copy - I compared the large ones byte-wise - not a single byte is different.
Looks like the copy function just copies the picture.

The replace-function is probably the only way to trigger a the creation of new versions of the photo apart from reuploading it.

Sebastian

Andy

rainforest1155 wrote:

That doesn't seem to trigger a recode - it's a 100% identical copy - I compared the large ones byte-wise - not a single byte is different.
Looks like the copy function just copies the picture.

The replace-function is probably the only way to trigger a the creation of new versions of the photo apart from reuploading it.

Sebastian

I wasn't sure - so figured I'd try. There are many secrets under the Smug-covers so I just didn't know

John - re-upload is the ticket....

rainforest1155

Andy wrote:

I wasn't sure - so figured I'd try. There are many secrets under the Smug-covers so I just didn't know

And it was a good idea - I found myself staring at both pictures in order to notice a difference first. When I compared the filesize it became clearer that there might be no difference at all.

Sebastian

jfriend

I found one that works, I think

Andy wrote:

I wasn't sure - so figured I'd try. There are many secrets under the Smug-covers so I just didn't know

John - re-upload is the ticket....

There are a bunch of operations that smugmug can do on an image. I was wondering if one of them would do no harm, but also trigger a re-make of the smaller sizes. The first one I tried was to rotate 90 degrees right, then 90 degrees left. It seems to work. The sky mountain boundaries are noticably better now.

Before on the left (45,384 bytes), After on the right (67,388 bytes).



I suspect that you could use some of the other tools too to apply a tiny crop, apply an unnoticable color effect, etc... Rotation is the easiest one I could think of that should be reversible, but might cause regeneration.

Andy

jfriend wrote:

There are a bunch of operations that smugmug can do on an image. I was wondering if one of them would do no harm, but also trigger a re-make of the smaller sizes. The first one I tried was to rotate 90 degrees right, then 90 degrees left. It seems to work. The sky mountain boundaries are noticably better now.

Before on the left (45,384 bytes), After on the right (67,388 bytes).

I suspect that you could use some of the other tools too to apply a tiny crop, apply an unnoticable color effect, etc... Rotation is the easiest one I could think of that should be reversible, but might cause regeneration.

cool!

jfriend

Can do a whole gallery at once too

Andy wrote:

cool!

And, since there's multi-select for rotation, it's easy to do this on a whole gallery.

Folks reading this thread from the beginning are going to get really confused because it now looks like your change fixed the problem too (because your message and my message point to the same, now changed images).

Andy

jfriend wrote:

And, since there's multi-select for rotation, it's easy to do this on a whole gallery.

Folks reading this thread from the beginning are going to get really confused because it now looks like your change fixed the problem too (because your message and my message point to the same, now changed images).

Fixed.

DavidTO

That would be a lossy rotation on the original JPEG, though, wouldn't it? Maybe negligible, but lossy nonetheless?

jfriend

Lossy or lossless rotation at Smugmug?

DavidTO wrote:

That would be a lossy rotation on the original JPEG, though, wouldn't it? Maybe negligible, but lossy nonetheless?

Is it lossy? I was wondering if this was lossless or lossy?

According to what I've read, it is possible to do lossless JPEG rotation if the image dimensions are divisible by 16 which apparently all out-of-camera sizes are. Does Smugmug do lossy or lossless rotation if the image dimensions are divisible by 16?

DodgeV83

jfriend wrote:

Is it lossy? I was wondering if this was lossless or lossy?

According to what I've read, it is possible to do lossless JPEG rotation if the image dimensions are divisible by 16 which apparently all out-of-camera sizes are. Does Smugmug do lossy or lossless rotation if the image dimensions are divisible by 16?

Smugmug does lossless rotation.

Andy

jfriend wrote:

Is it lossy? I was wondering if this was lossless or lossy?

According to what I've read, it is possible to do lossless JPEG rotation if the image dimensions are divisible by 16 which apparently all out-of-camera sizes are. Does Smugmug do lossy or lossless rotation if the image dimensions are divisible by 16?

We check first, if the image is divisible by 8 on both sides it will rotate losslessly.