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MARCO WERMAN: While there's no official word from the Mousavi camp, the chatter on Twitter and other social media is that the opposition protest tomorrow will go ahead. Some Iranians have been calling the BBC to give their views. This is Akbar, a 65-year-old protestor that we've heard from a couple of times this week. He says the meaning of Ayatollah Khamenei's speech today was clear.
AKBAR: It's a threat. It's an outright threat that he's going to mow down anybody who comes out into the streets.
WERMAN: Other callers agree. Some appear to be in a defiant mood. One man identified himself as Behrooz, a student in Tehran. He mentioned the basiji, Iran's infamous government militia.
BEHROOZ: This mass of people that are protesting is very huge. Millions. One million. Two million. If we were 2,000 strong, they can scare us with 200 basijis. But if we are a million, what can they do? They can do nothing. Actually, they will become more dangerous but we won't stop.
WERMAN: Two of the many Iranian callers who have contacted the BBC today. As the situation in Iran evolves, it's gotten more and more difficult to get information from inside the country. The government has tried to keep journalists from covering the protests, and it's tried to restrict the protesters use of mobile phone networks and the Internet. But Iranians have continued to turn to new media in record numbers. And that's prompted three US tech companies to roll out new Persian language tools. Here's more from reporter Cyrus Farivar.
CYRUS FARIVAR: Late last night, Facebook announced on its blog that it would be making its popular social networking site available for the first time in the Persian language. At about the same time, Google added a new online translation tool for Persian. Finally, Apple's new iPhone software, released just two days ago, includes Persian support. That means that Persian speakers can now send text messages in their own language for the first time on the iPhone.
HAMID TEHRANI: I think it's very helpful and it's very timely.
FARIVAR: That's Hamid Tehrani. He writes under a pseudonym for GlobalVoicesOnline.org, a blog collective.
TEHRANI: It's really a testimony to the importance of Internet in general, regarding the events happening in Iran and how Iranians are one of the massive users of this medium at the moment for a cause that has captured the world's imagination all over.
FARIVAR: Google's translation software is probably the most useful for English speakers, as it allows for translation of both Persian into English and English back into Persian. But these are ï¿½machine translationsï¿½, and have very little human input. Basically, the company writes software that can ï¿½learnï¿½ how to interpret those languages based on a set of rules, explains Peter Norvig, the director of research at Google.
PETER NORVIG: There's two parts to it. The important part is this translation model, where we do need the identical text, we need the same article in English and in Persian. And then there's also ï¿½ we build up a language of the individual languages. We for a long time has been a model in English, and we've also built a separate model in Persian. So we ask both what is a good translation and given that we've got a good translation, is it a good sentence in Persian?
FARIVAR: When I first tried it, Google's translation of the sentence, ï¿½Hello, my name is Cyrus,ï¿½ wasn't quite right. It gave me back a Persian version that translated as ï¿½Hello, my name Karoosh is.ï¿½ The name difference has to do with different versions of the same name. Still, I found it surprising that it's taken so long for Google to release a Persian translation tool, when it already has tools out there for many languages with fewer speakers, like Estonian.
NORVIG: I guess we've been working on translation altogether since 2002. We've been adding languages as we go. We're up to 42 languages, and it really just depends on how much data we can get. We build our systems with a machine-learning approach that depends on looking on lots of examples of translations. So even though there's fewer speakers, it was easier to get more examples of Estonian than some of the other languages like Persian and so it took us longer to get there.
FARIVAR: Still, many Iranians like Hamid Tehrani would like to see more Persian-language software available. He complains that he still can't send Persian text on his Blackberry.
TEHRANI: But my complaint is that there's so much that the tech community could be doing by acknowledging that Persian is the language of 70 million people in Iran, and many more in Central Asia and Afghanistan. And I just don't see the recognition and I find that almost just a discriminatory policy.
FARIVAR: Despite Google's imperfect translation, the company acknowledges that it is still in the ï¿½alphaï¿½ stage of development. Persian speakers can contribute their suggestions to improve the service at Google's translation page. For The World, I'm Cyrus Farivar