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Ending Image Compression confusion


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It was drawn to my attention today that a proportion of content creators are operating under the misguided understanding of how textures work in Second Life, and when I explain why, you'll understand how this came to be.

I should note that this "revelation" was an eye opener to me, one of those biases we all have whereby we end up assuming people know something because we know it and believe that knowledge to be universal.

So let me put this problem to rest.

In Second Life textures are lossily compressed. That's it, goodnight.

OK so that is not the full story, but it really is the truth for almost every texture you upload/download in SL. 

Textures in Second Life are compressed by the viewer of the  creator at the time of upload, they are compressed in Jpeg2000 using a lossy algorithm, this means higher compression, lower download times at the cost of fidelity. Many of you are nodding and know this to be the case, but it would seem that a number of people don't realise. Moreover they believe that their textures are uploaded as lossless. "Wait, what? why?" I hear you cry. Well here's the problem. 

90e86c21510415fb92c5b50d1d5761ab.png

Oh look there's a 512x512 texture about to be uploaded. Underneath it we see a nice little checkbox, it is disabled, so we can't actually do anything with it, but it has a tick in it so *yay*, we're going to get lossless uploads, right? Right?

Nope. 

Sadly this has been that way for about 12 years. So long that I've never given it another thought until today. The lossless upload option applies only to small images (see below for clarification on "small"), it was introduced to help avoid compression artefacts making a mess of sculpt maps, the option never applied to large textures.

Unless you happen to know why that box is there, and the history of it, you could quite reasonably surmise that that tick box is telling you the exact opposite of what is really going to happen when you click upload.

So what are the facts:

1) Images with 16K pixels or less (that is a max of 128x128, 256x64, 512x32, 1024x16) are optionally uploaded as lossless.  
2) Images with more than this, have no option, they are always lossy, no ifs, no buts. <--- this means pretty much every texture you are likely to use.

What is being shown to you is actually a global setting in the viewer that actually means "I would like small images to be uploaded lossless please". It means nothing more, it is being shown as disabled because back in the day when this was implemented, the developer making this change decided that disabling it conveyed the meaning that it was not applicable to this texture, an ambiguity that has persisted forever it seems.

As of the next Firestorm release, this option will no longer appear for large images to which it can never apply. I have also raised a Jira to the lab to get a fix for this into their viewer. Other viewers may already have cleaned this up (I've not checked).  The tick box will still appear for small images only and you'll be able to toggle it for them. Hopefully this will help rid us of this misinformation. In the meantime, if you hear this falsehood being perpetuated feel free to correct the individual, you'll be saving them a lot of heartache and head scratching.

1e7476d7fbc143d1fe3852e85ec47b07.png04807880fb39ae29be96a6ee772c6e84.png

 

 

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Thank you Beq for that explanation 🙂

Not to derail this, but what is the message at the bottom of the 2 images referring to? "Fee is based on your subscription level. Higher levels are charged lower fees. Learn more." https://gyazo.com/23c006f24db20acc0e0685ce69c31296

Has there been an announcement about the new subscription levels and benefits and the timeline for their implementation? 

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On 3/19/2020 at 10:04 AM, Arwen Serpente said:

Thank you Beq for that explanation 🙂

Not to derail this, but what is the message at the bottom of the 2 images referring to? "Fee is based on your subscription level. Higher levels are charged lower fees. Learn more." https://gyazo.com/23c006f24db20acc0e0685ce69c31296

Has there been an announcement about the new subscription levels and benefits and the timeline for their implementation? 

The (technical) changes have rolled out this week on the LL viewer, LL viewer users will already be seeing this. All other (maintained) viewers will follow suit in due course. 

I say "technical" because all that is in place now are the UI and serverside hooks for a future where there will be differentiation at the subscription level for the costs of various things.

To my knowledge the plans to put these in place are in process but they are unlikely to appear for a little while, they want to make sure that the changes themselves are well established before fiddling with the levels. I am sure a passing Linden such as @Grumpity Linden could give more correct answer.

Newer viewers will incorporate these changes and reflect the proper charges as they appear. The next version of Firestorm for example will. Hence you see the new text because my changes are part of that build as well. 

Older viewers that do not have the changes will still work (for the most part) but you, the user, will get misleading indications of costs because the viewer will estimate the costs based on "old knowledge" and the server will charge you based on the correct charges under the new regime.

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19 minutes ago, Beq Janus said:

The (technical) changes have rolled out this week on the LL viewer, LL viewer users will already be seeing this. All other (maintained) viewers will follow suit in due course. 

I say "technical" because all that is in place now are the UI and serverside hooks for a future where there will be differentiation at the subscription level for the costs of various things.

To my knowledge the plans to put these in place are in process but they are unlikely to appear for a little while, they want to make sure that the changes themselves are well established before fiddling with the levels. I am sure a passing Linden such as @Grumpity Linden could give more correct answer.

Newer viewers will incorporate these changes and reflect the proper charges as they appear. The next version of Firestorm for example will. Hence you see the new text because my changes are part of that build as well. 

Older viewers that do not have the changes will still work (for the most part) but you, the user, will get misleading indications of costs because the viewer will estimate the costs based on "old knowledge" and the server will charge you based on the correct charges under the new regime.

Thanks Beq for replying.

@Grumpity Linden So changes to subscription levels are coming (we know that). But to start dribbling out changes like this which have a financial impact on residents without an announcement of the full program is putting the cart before the horse. The program should be announced with an implementation date, and then, changes to viewers can start to be implemented. Doing it like this just sows confusion for the general population. For Merchants in particular, who are especially impacted, it appears to be another fee increase without knowing what benefit is associated to make it worthwhile. The fees levied against Merchants are rising rapidly (cash out fees, MP commission fees, etc). SL Merchants need a full picture of what is planned for 2020 (subscription changes and all fee changes) in order to plan our businesses.

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These are only hooks for future functionality and no differences in fees will ever roll out unannounced.  Due to having open source products with multiple TPVs we're unable to roll out the UI work all at once with the actual feature changes.

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14 minutes ago, Alexa Linden said:

These are only hooks for future functionality and no differences in fees will ever roll out unannounced.  Due to having open source products with multiple TPVs we're unable to roll out the UI work all at once with the actual feature changes.

When LL is ready to announce the new subscription levels and their benefits, costs, etc, make the announcement in advance of it going live (that's what's been done in the past for other major changes).
 
For instance, on XXdate, announce to residents "New Subscription Levels!", outline the changes and new benefits. Let residents know that the change will go live one month later on XXdate.  Then indicate that between now and then, they may notice some changes to the UI to accommodate these new levels.  That's in preparation for the changeover and will not be implemented until June 1.
 
Third party viewers will be able to update UIs during that time.  Slipping in UI changes now without explanation leads to confusion and questions - just like I just had. I'm sure I won't be the only one who brings it up when those changes start to appear.
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On 3/20/2020 at 9:28 PM, Arwen Serpente said:
When LL is ready to announce the new subscription levels and their benefits, costs, etc, make the announcement in advance of it going live (that's what's been done in the past for other major changes).
 
For instance, on XXdate, announce to residents "New Subscription Levels!", outline the changes and new benefits. Let residents know that the change will go live one month later on XXdate.  Then indicate that between now and then, they may notice some changes to the UI to accommodate these new levels.  That's in preparation for the changeover and will not be implemented until June 1.
 
Third party viewers will be able to update UIs during that time.  Slipping in UI changes now without explanation leads to confusion and questions - just like I just had. I'm sure I won't be the only one who brings it up when those changes start to appear.

I am absolutely certain that the Lab will be announcing the changes well in advance. they have always done so in the past. However, in order to lay the groundworks for more flexibility in the packages that the lab provide they have needed to added some specific new "hooks" as @Alexa Linden noted. The lab viewer has rolled out with those new hooks in place, but with TPVs such as Firestorm who have a less frequent release cadence these things have to be scheduled well ahead of public announcements, and more importantly the lab have limited control over our release cycle. We are not allowed to merge features until the lab have them in a beta release, in practice we don;t merge them until they release, or we end up constantly re-merging changes that are still in flux. Once we are ready , and we consider that enough time has passed since the last release, we begin our QA/beta cycles and based on that feedback we may have a number of iterations until finally delivering a release. It would be hard for the lab to plan around our schedule so I don't find it surprising that they aren't able to put a date to things now. Ideally they will want people to have access to the new features before launching the new structures; ss such these need to be seeded early to give us a chance. This is not to say that they'll wait indefinitely of course, if FS was not able to release for whatever reason, in the end the lab will simply push ahead, but they have to put all of this into their planning considerations. 

That said the "premium plus" conversation has been ongoing in the public user group meetings for a while now. I would expect that blogers such as @Inara Pey have mentioned these in their weekly meeting update posts. The changes were also noted in the release notes for the LL viewer. https://releasenotes.secondlife.com/viewer/6.3.8.538264.html what you saw in my images was the Firestorm version of those, which we will have in our release notes "when" the time comes. The confusion is therefore mostly my fault, I was previewing a future release feature for you.

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On 3/27/2020 at 12:24 PM, Beq Janus said:

IThat said the "premium plus" conversation has been ongoing in the public user group meetings for a while now. I would expect that blogers such as @Inara Pey have mentioned these in their weekly meeting update posts.

I'll continue to cover Premium Plus (and other changes through my weekly summaries, as mention is made / updates are provided. For the Premium aspects, news generally comes through the monthly Web User Group meetings which I attempt to summarise ASAP after each meeting. I also attempt to provide information on all technical. etc., updates and releases through a variety of reports, often in support of the Lab's own blogging.

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