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Silvestris est projet de logiciels libres de traduction assistée par ordinateur (TAO) et de mémoires de traduction.
Nous utilisons autant que possible la Licence Publique de l'Union Européenne (EUPL), actuellement dans sa version 1.1 (lisez aussi ici nos commentaires à propos de la licence EUPL 1.2). Malheureusement la licence EUPL a quelques incompatibilités avec d'autres licences (la GPLv3 pour OmegaT, ou des licences de logiciels commerciaux par exemple). C'est pourquoi certains de nos projets, liés à un produit tiers, peuvent être distribués sous une autre licence pour rester compatible avec celle de ce dernier. Dans le cas où l'autre licence interdit la publication du code source (ou reste floue sur le sujet), nous ne le diffusons pas, mais le logiciel proprement dit reste gratuit.
Peut-être pouvez-vous considérer que le projet n'est pas totalement gratuit (mais néanmoins libre) dans la mesure où nous proposons un service d'hébergement payant. Mais ce service n'a rien d'obligatoire: si vous arrivez à installer un serveur vous-même, alors vous n'en avez tout simplement pas besoin. Si au contraire un tel service peut vous aider, alors merci de ne pas oublier qu'il a un coût, et qu'en le payant vous contribuez à financer le projet dans son ensemble.
Silvestris, in latin, is an adjective related to wood (silva). It can also have the meaning of wild, savage. Originally the plan was to create a free web CAT tool, which could be understood as wild CAT, so we made the reference with silvestris felis, the wild version of your familiar cat. When we finally decided to go step by step, creating several smaller tools, we kept the word silvestris and used for other subprojects, names from the official international animals taxonomy, in latin. For example, Cyclotis is the reference to african forest elephant, which is not the best known species of elephant but semt to reflect correctly the spirit of a short term translation memory.
First you can open an account to this web site and participate in the forum. We perfectly know that it was not possible until very recently: the reason is that this web site received a lot of spammer accounts (more than 100 a day!) meaning that we had to temporarily switch off registration until we could find a solution. And this temporarily situation was finally durable. Now we installed an anti-spammer plugin for Drupal, which reduces the problem but does not completely remove it. As a consequence we adopt the following rule: please register only when you plan to use the forum, because if you register and send nothing, your account will be included in the list of spamming accounts which are regularly deleted.
For technical contributions, you may also register to the forge, which has never been closed for registration. However, this forge does not always send e-mail notifications, so if you receive no answer, consider to use the forum as well.
The two projects are maintained by the same person, but not in the same conditions. DGT-OmegaT is a project from the European Commission, containing what they decide to put in, while Silvestris is a personal project, designed at home. The fact that Silvestris uses EUPL license has nothing to do with the link between the two projects: this is only the license I prefer.
Another link between the two projects is that what they call TeamBase is nothing more than a customized version of Silvestris Cyclotis. Except for the name, most of what you can read in DGT-OmegaT web site about TeamBase is perfectly valid for Cyclotis - so, instead of repeating the same things in two locations, we invite you to read both web sites. Also DGT-OmegaT already includes the Cyclotis plugin, while OmegaT would need some adaptations (but the code for them is already available). It is probably a good idea that you use DGT-OmegaT to test Cyclotis, before we open an RFE for OmegaT to have the patches included in the original version as well.
Cyclotis database is optimized to reply fast, as well for reading or writing, but in the condition that the table contents remains small. When the table grows after, let's say, aroud 10 000 segments, it becomes slower and would require an other kind of indexation. If you don't delete your memories, you will want to join them and as a result, you will after complain about performances. For long-term memories, we would still use Postgresql but with the choice of another table schema organisation. And it would be better to use it in batch mode, that is, send and receive lot of segments in one step rather than trying to answer at real time.
Using the function EXPLAIN PLAN from Postgres, we discovered that indexes were used for SELECT queries only if there were more than approximately 10 000 segments. However, they are filled at any time, meaning that UPDATE or INSERT queries become slower while SELECT queries are not faster. That's one of the reasons why we think that Cyclotis should remain a short-term database (see previous answer) : for a long-term database we would use different optimizations, and indexation is one of them which is only efficient on big databases (in the case of Postgresql).
Fuzzy matches inside Cyclotis make use of the Postgres package "pg_trgm", for which I do not know any equivalent in MySQL or other open source servers. If you want to port this service to another server, either you find an equivalent or you will have to limit the power, for example using exact searches or retreiving all results. Glossary search uses the module tsearch2 and is not portable for the same reason.
We did sucessfully execute an OmegaT project mode using other databases, since this mode uses only exact search, which is an SQL standard. So, we know that almost for this service, this is possible. But we do not provide a plugin for it, because it is only valid for this mode and we may add in the future some other optimisations, in case portability could be not possible in the future.
Most Computer Assisted Translation tools are proprietary and don't offer a plugins API, especially for translation memories or direct access to project or editor (while they usually do for Machine Translators). This is probably because most of them also promote their own server solution for translation memory. However, if you think that you are able to implement such a plugin for your favorite CAT tool, please tell us so and we will be proud to give you all necessary information about Cyclotis (like our server protocol) to make it possible to do so. You can find here a short documentation but it is far from being complete.
The purpose of these libraries is to be used in most common CAT tools, and most CAT GUIs are written either in Java or in .NET: the idea is that it would enable to write plugins which use the Ruby classes rather than rewriting them in the target programming language. Maybe it will be slower but it will ensure perfect compatibility between all platforms, even if they change in the time.
Except maybe Culter, most of them should be considered as highly experimental for the moment. Only Cyclotis is really mature.
When you create a database schema, you generally add indexes: this sounds perfectly natural. But in the case of Cyclotis, as a big surprise, we discovered that most often, the SELECT queries did not use the indexes (they do not appear in an EXPLAIN PLAN), even if they exist, until the database grows to a certain limit. So, in this case, indexes have a cost during UPDATE without any gain during SELECT.
Most translation projects are in the just mentioned limit. So we consider that a database which is created for one translation and destroyed immediately after has no reason why to be indexed. Unless we finally receive an explanation about why the indexes were not used...
Note: the possibility to index a Cyclotis memory is available, but not set by default. In the SaaS server, the rule is that memories are not indexed during creation, but they are automatically indexed when you renew a memory (because when you do it, we hope that the memory is now big enough to take profit from the indexes).
Another difference is that Cyclotis makes use of GiST indexes, while Elefas uses GiN indexes. According to PostgreSQL documentation, GiST indexes are better for dynamic searches while GiN are indicated for more static data - and this is precisely, the biggest difference between Cyclotis and Elefas!
Even with indexes, a big database can have poor performances if hundreeds of users are connected at the same time. For that reason, we find a compromise: the big database, which contains everything, should be only accessed in batch mode, then data are extracted to a Lucene index which can accept an high number of users (since it is local and read-only, the "connection" dos not even consume any resource)