6 ms·

Improving support for adult content on Mastodon

217 points by zach43 7y ago

lifthrasiir 7y ago
There is a Ruby port [1] publicly available. From the encoding routine [2], it seems to be an sRGB correction followed by a two-dimensional DCT. The first two bytes encode parameters---the size of the output matrix n x m and the quantization scale used for ACs; next 4 bytes encode the DC, then (nm-1) quantized ACs (2 bytes per AC) follow. The comparison to Facebook's similar solution [3] would be interesting (but I realize that Blurhash tries to hide explicit images, so technically they have different goals). [1] https://github.com/Gargron/blurhash/ https://github.com/Gargron/blurhash/ [2] https://github.com/Gargron/blurhash/blob/master/ext/blurhash/encode.c https://github.com/Gargron/blurhash/blob/master/ext/blurhash... [3] https://code.fb.com/android/the-technology-behind-preview-photos/ https://code.fb.com/android/the-technology-behind-preview-ph...
- WAHa_06x36 7y ago
  I created the algorithm, and there is a proper release of it with documentation and implementations in a few languages coming... "soon". It's a work project, so trying to find time to work on it is always tricky. If you have any questions, feel free to ask. The main goal of it is to be a placeholder while images load, but it also has a nice secondary use for hiding sensitive images here. Other aims of the algorithm is to be very simple and easy to implement, and to use very small amounts of data to make it comfortable to include in databases and responses (Facebook uses 200 bytes of data, BlurHash uses around 30, depending on settings.)
  - jim-jim-jim 7y ago
    Off topic but I did a double take when I scrolled past your name. Are you the same guy who did some kind of imageboard related stuff years ago? I know that's vague, but my brain is fried and I can't remember why I remember you.
    - WAHa_06x36 7y ago
      Many, many years ago, yes. Well remembered.
      - claudiawerner 7y ago
        I'd just like to say thanks for creating Wakaba and Kareha and furthering internet culture (and its study). I can't begin to recount the times I had hosting a small board with a few friends and of course the good experience on all the Wakaba boards I used, and my blog which for a while was running on an admin-OP-only basis. Wakaba was arguably what got me into Perl.
    - robobro 7y ago
      trev and acostoss (from our same community) are also lead devs on mastodon.
      - halcy 7y ago
        They both aren't really anymore, but they do hang out.
BlackLotus89 7y ago
Reminds me of https://news.ycombinator.com/item?id=15053064 https://news.ycombinator.com/item?id=15053064 I normally hate this kind of blur and I'm not sure if this is worth such a big release note. I normally see such filters applied (forced on users by platform conventions), requiring a login to "unlock" and often you find yourself wondering why it was blocked in the first place.... Could be good to hide spoilers thought
- WAHa_06x36 7y ago
  This is used for sensitive images, but also as a placeholder while the full image loads, as the entire blurred image can easily be contained in the JSON data (it's around 30 characters long).
WilliamEdward 7y ago
I really like the idea of Mastodon, but i can't shake this feeling that their name is kind of awful. I get that they're not trying to be exactly like twitter but by comparison, twitter is a much bubblier and friendlier word.
- olah_1 7y ago
  And the language of "toot" is extremely hokey and will never be taken seriously. It implies farting for most Americans. "Tweet" reminds people of birds. As in "a little bird told me". Which is appropriate for a gossip style network.
  - jonnycomputer 7y ago
    mastodon's tooting...
    - echelon 7y ago
      Exactly, it's really gross. This isn't going to catch on in the mainstream. Mastodon seriously needs a rebrand.
      - gsich 7y ago
        It works in german. "tröten", also the original developer is from germany.
        jamesrcole 7y ago
        Social communications software is all about the number of users. It needs to able to catch on everywhere. A term that sounds embarassing to many of its potential users is a real problem.
        iamnothere 7y ago
        As a modestly funded project, Mastodon is never going to achieve "hockey stick" growth, and it would probably be overwhelmed if this happened. It's better for them to pursue a strategy of gradual, steady growth. Mastodon is continuing to grow steadily, and it does so in the face of established players who can outspend and outrun them. 2 million users is pretty damn good for an open source project that doesn't have a marketing budget to speak of. In addition, it's time to drop the notion that every platform has to serve every type of user. As demonstrated by the problems facing Twitter, it is probably better to have many different platforms serving different audiences. Mass media inevitably reaches for the lowest common denominator.
deleted 7y ago
[deleted]
barbs 7y ago
I feel like "BlurHash" is a misleading name, since it's not a hash of the image data that gets created, it's just highly compressed to just some data about the colours used. Unless I'm misunderstanding something?
- omegaworks 7y ago
  Technically speaking, a hash is just a function that maps arbitrary data into a fixed size set of outputs. f(x) = 1 is a hash function. A catastrophically bad one to use for something like a hashmap, but a hash function nonetheless.
  - philwelch 7y ago
    Although if you’re implementing a hashmap from scratch, that is a very good hash function to use temporarily while building collision management.
- viraptor 7y ago
  You could say that hash is a very aggressive, lossy compression. Same image will result in same hash. Different images will often result in different hashes. That makes it a valid hash.
  - piaste 7y ago
    > You could say that hash is a very aggressive, lossy compression. You could but it would be about as misleading as a sentence could possibly be. The purpose of compression is to preserve content as much as possible: similar inputs should give similar outputs, and the output should provide as much information about the input as it can. Hashing deliberately does the exact opposite - slightly different inputs should give wildly different outputs - as its primary purpose in the case of crypto hashes, and in the case of index hashes as a performance optimization (which is the primary purpose of index hashes).
    - MattJ100 7y ago
leshokunin 7y ago
How does Mastodon handle governance for content that gets reported? It sounds like a logistics nightmare. It's nice that the apps are getting a way to blur things, but I would imagine that the bigger problem would be bad actors running instances, and finding ways to keep them away.
- proactivesvcs 7y ago
  Mastodon doesn't. It's the software. Instance (server) administrators and moderators choose to handle reports.
- halcy 7y ago
  One nice thing about a federated system is that admin work is also distributed. I run a small server that has existed for a long time (and has knowledge of / federates to some extent with most of the fediverse as such), and my co-moderator and me have a very manageable administration workload (mind: you only have to moderate content that actually arrives at your instance, not all content that is posted everywhere ever). The Mastodon software (and most other fediverse software) has multiple tools for this specifically. On our instance, we do not allow "untagged" (not hidden behind a content warning) pornographic content. If an instance allows this, we "silence" them - meaning that none of their content shows up on any public timeline anymore. People can still follow users from there, but that's their choice, and none of my business - and nobody is getting a facefull of tiddy if they don't specifically want it. If an instance is generally acting in good faith, but allows images that I definitely do not want cached locally, another tool you have is "media reject" an instance - in that case, no media from that instance will be downloaded. Can still follow, but have to click through for images, and no thumbnails. We try to avoid this, but, you know. The nuclear option is to just defederate from an instance entirely. We also try to avoid this, but it's a very effectice "ugh god I'm not dealing with this" tool. edit: That's on a macro level, of course - we can also do the same thing to single users, and that's obviously preferred if it's just one idiot. a user submitting a report can also choose to forward the report the the originating server, which can be helpful to get a problem at the root.
deleted 7y ago
[deleted]
coldacid 7y ago
Now if only certain instances would actually default to marking all their content as adult content. This is great to have but useless when certain 18+ instances just bare all kinds of smut clear to the timeline. (I'm talking mainly of the *blr instances, in case you haven't already hidden them for yourselves.)

217 points by zach43 7y ago

There is a Ruby port [1] publicly available. From the encoding routine [2], it seems to be an sRGB correction followed by a two-dimensional DCT. The first two bytes encode parameters---the size of the output matrix n x m and the quantization scale used for ACs; next 4 bytes encode the DC, then (nm-1) quantized ACs (2 bytes per AC) follow. The comparison to Facebook's similar solution [3] would be interesting (but I realize that Blurhash tries to hide explicit images, so technically they have different goals). [1] https://github.com/Gargron/blurhash/ https://github.com/Gargron/blurhash/ [2] https://github.com/Gargron/blurhash/blob/master/ext/blurhash/encode.c https://github.com/Gargron/blurhash/blob/master/ext/blurhash... [3] https://code.fb.com/android/the-technology-behind-preview-photos/ https://code.fb.com/android/the-technology-behind-preview-ph...

WAHa_06x36 7y ago
I created the algorithm, and there is a proper release of it with documentation and implementations in a few languages coming... "soon". It's a work project, so trying to find time to work on it is always tricky. If you have any questions, feel free to ask. The main goal of it is to be a placeholder while images load, but it also has a nice secondary use for hiding sensitive images here. Other aims of the algorithm is to be very simple and easy to implement, and to use very small amounts of data to make it comfortable to include in databases and responses (Facebook uses 200 bytes of data, BlurHash uses around 30, depending on settings.)
- jim-jim-jim 7y ago
  Off topic but I did a double take when I scrolled past your name. Are you the same guy who did some kind of imageboard related stuff years ago? I know that's vague, but my brain is fried and I can't remember why I remember you.
  - WAHa_06x36 7y ago
    Many, many years ago, yes. Well remembered.
    - claudiawerner 7y ago
      I'd just like to say thanks for creating Wakaba and Kareha and furthering internet culture (and its study). I can't begin to recount the times I had hosting a small board with a few friends and of course the good experience on all the Wakaba boards I used, and my blog which for a while was running on an admin-OP-only basis. Wakaba was arguably what got me into Perl.
  - robobro 7y ago
    trev and acostoss (from our same community) are also lead devs on mastodon.
    - halcy 7y ago
      They both aren't really anymore, but they do hang out.

BlackLotus89 7y ago

Reminds me of https://news.ycombinator.com/item?id=15053064 https://news.ycombinator.com/item?id=15053064 I normally hate this kind of blur and I'm not sure if this is worth such a big release note. I normally see such filters applied (forced on users by platform conventions), requiring a login to "unlock" and often you find yourself wondering why it was blocked in the first place.... Could be good to hide spoilers thought

WAHa_06x36 7y ago
This is used for sensitive images, but also as a placeholder while the full image loads, as the entire blurred image can easily be contained in the JSON data (it's around 30 characters long).

WilliamEdward 7y ago

I really like the idea of Mastodon, but i can't shake this feeling that their name is kind of awful. I get that they're not trying to be exactly like twitter but by comparison, twitter is a much bubblier and friendlier word.

olah_1 7y ago
And the language of "toot" is extremely hokey and will never be taken seriously. It implies farting for most Americans. "Tweet" reminds people of birds. As in "a little bird told me". Which is appropriate for a gossip style network.
- jonnycomputer 7y ago
  mastodon's tooting...
  - echelon 7y ago
    Exactly, it's really gross. This isn't going to catch on in the mainstream. Mastodon seriously needs a rebrand.
    - gsich 7y ago
      It works in german. "tröten", also the original developer is from germany.
      - jamesrcole 7y ago
        Social communications software is all about the number of users. It needs to able to catch on everywhere. A term that sounds embarassing to many of its potential users is a real problem.
        iamnothere 7y ago
        As a modestly funded project, Mastodon is never going to achieve "hockey stick" growth, and it would probably be overwhelmed if this happened. It's better for them to pursue a strategy of gradual, steady growth. Mastodon is continuing to grow steadily, and it does so in the face of established players who can outspend and outrun them. 2 million users is pretty damn good for an open source project that doesn't have a marketing budget to speak of. In addition, it's time to drop the notion that every platform has to serve every type of user. As demonstrated by the problems facing Twitter, it is probably better to have many different platforms serving different audiences. Mass media inevitably reaches for the lowest common denominator.

deleted 7y ago

[deleted]

barbs 7y ago

I feel like "BlurHash" is a misleading name, since it's not a hash of the image data that gets created, it's just highly compressed to just some data about the colours used. Unless I'm misunderstanding something?

omegaworks 7y ago
Technically speaking, a hash is just a function that maps arbitrary data into a fixed size set of outputs. f(x) = 1 is a hash function. A catastrophically bad one to use for something like a hashmap, but a hash function nonetheless.
- philwelch 7y ago
  Although if you’re implementing a hashmap from scratch, that is a very good hash function to use temporarily while building collision management.
viraptor 7y ago
You could say that hash is a very aggressive, lossy compression. Same image will result in same hash. Different images will often result in different hashes. That makes it a valid hash.
- piaste 7y ago
  > You could say that hash is a very aggressive, lossy compression. You could but it would be about as misleading as a sentence could possibly be. The purpose of compression is to preserve content as much as possible: similar inputs should give similar outputs, and the output should provide as much information about the input as it can. Hashing deliberately does the exact opposite - slightly different inputs should give wildly different outputs - as its primary purpose in the case of crypto hashes, and in the case of index hashes as a performance optimization (which is the primary purpose of index hashes).
  - MattJ100 7y ago

leshokunin 7y ago

How does Mastodon handle governance for content that gets reported? It sounds like a logistics nightmare. It's nice that the apps are getting a way to blur things, but I would imagine that the bigger problem would be bad actors running instances, and finding ways to keep them away.

proactivesvcs 7y ago
Mastodon doesn't. It's the software. Instance (server) administrators and moderators choose to handle reports.
halcy 7y ago
One nice thing about a federated system is that admin work is also distributed. I run a small server that has existed for a long time (and has knowledge of / federates to some extent with most of the fediverse as such), and my co-moderator and me have a very manageable administration workload (mind: you only have to moderate content that actually arrives at your instance, not all content that is posted everywhere ever). The Mastodon software (and most other fediverse software) has multiple tools for this specifically. On our instance, we do not allow "untagged" (not hidden behind a content warning) pornographic content. If an instance allows this, we "silence" them - meaning that none of their content shows up on any public timeline anymore. People can still follow users from there, but that's their choice, and none of my business - and nobody is getting a facefull of tiddy if they don't specifically want it. If an instance is generally acting in good faith, but allows images that I definitely do not want cached locally, another tool you have is "media reject" an instance - in that case, no media from that instance will be downloaded. Can still follow, but have to click through for images, and no thumbnails. We try to avoid this, but, you know. The nuclear option is to just defederate from an instance entirely. We also try to avoid this, but it's a very effectice "ugh god I'm not dealing with this" tool. edit: That's on a macro level, of course - we can also do the same thing to single users, and that's obviously preferred if it's just one idiot. a user submitting a report can also choose to forward the report the the originating server, which can be helpful to get a problem at the root.

deleted 7y ago

[deleted]

coldacid 7y ago

Now if only certain instances would actually default to marking all their content as adult content. This is great to have but useless when certain 18+ instances just bare all kinds of smut clear to the timeline. (I'm talking mainly of the *blr instances, in case you haven't already hidden them for yourselves.)