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 Inviato: 30 Set 2009 14:30 Oggetto: Theora 1.1, il codec video open source |
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Commenti all'articolo Theora 1.1, il codec video open source
Thusnelda, l'ultima versione del codec, sarebbe in grado di rivaleggiare con H.264.
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etabeta
Dio maturo
Registrato: 06/04/06 10:02
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| Inviato: 30 Set 2009 21:49 Oggetto: |
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Cominciamo a inondare i circuiti p2p di file ogg così almeno i windowsiani e i melisti saranno obbligati ad adeguarsi!
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mda
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Registrato: 01/11/06 09:39
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Residenza: Figonia
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| Inviato: 01 Ott 2009 05:58 Oggetto: |
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| etabeta ha scritto: | Cominciamo a inondare i circuiti p2p di file ogg così almeno i windowsiani e i melisti saranno obbligati ad adeguarsi!
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Con un convertitore trovato in rete (open) avrei tramutato avi in ogg.
Malgrado mi dica che avrei abbassato la qualità, non noto differenza di qualità (anzi è più fluido) video/suono, ma mi ritrovo qualche bel mega in meno!
ogg è un contenitore e quindi dovrei aver peggiorato le cose!
Come è possibile ? Il fatto che spesso la qualità dell'immagine non riesci ad guastarla nemmeno sul monitor ma anzi rallenta la fluidità per il maggior carico elaborativo! Questo perchè mi ritrovo dentro un file Theora 1.
Dunque H264 è inutile salvo qualche occhio di lince. Adesso poi.
Ciao |
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zero
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Registrato: 22/03/08 17:34
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| Inviato: 01 Ott 2009 08:58 Oggetto: |
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| mda ha scritto: |
...non noto differenza di qualità (anzi è più fluido) video/suono, ma mi ritrovo qualche bel mega in meno!
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Lo scopo e' proprio questo, stessa qualita' in files piu' snelli
| mda ha scritto: |
ogg è un contenitore e quindi dovrei aver peggiorato le cose!
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Anche avi e' un contenitore.
| mda ha scritto: |
Dunque H264 è inutile salvo qualche occhio di lince. Adesso poi.
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Ottenere gli stessi risultati usando files piu' piccoli ti sembra inutile? |
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giorgiobis
Eroe
Registrato: 30/03/09 22:01
Messaggi: 53
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| Inviato: 01 Ott 2009 10:47 Oggetto: |
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| al momento il mio interesse per i formati opensource riguardano la durabilità: cioè con tutti i porno scaricati magari in futuro non ci saranno più i codec proprietari o le vecchie versioni saranno buttate via, invece per gli opensource in linea di principio li si può adattare ai nuovi pc quantistici. |
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mda
Dio maturo
Registrato: 01/11/06 09:39
Messaggi: 6648
Residenza: Figonia
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| Inviato: 01 Ott 2009 15:04 Oggetto: |
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| zero ha scritto: | | mda ha scritto: |
Dunque H264 è inutile salvo qualche occhio di lince. Adesso poi.
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Ottenere gli stessi risultati usando files piu' piccoli ti sembra inutile? |
Mi sembra inutile avere una qualità che NON puoi godere perchè non vedi le differenze. Differenze, insomma, che esistono solo sulla carta.
Meglio la bassa occupazione di memoria e la velocità.
Come avere una Ferrari e girare in città! Alla fine è meglio la 500.
Ciao |
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zero
Dio maturo
Registrato: 22/03/08 17:34
Messaggi: 1947
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| Inviato: 03 Ott 2009 11:54 Oggetto: |
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| mda ha scritto: | | zero ha scritto: | | mda ha scritto: |
Dunque H264 è inutile salvo qualche occhio di lince. Adesso poi.
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Ottenere gli stessi risultati usando files piu' piccoli ti sembra inutile? |
Mi sembra inutile avere una qualità che NON puoi godere perchè non vedi le differenze. Differenze, insomma, che esistono solo sulla carta.
Meglio la bassa occupazione di memoria e la velocità.
Come avere una Ferrari e girare in città! Alla fine è meglio la 500.
Ciao |
Lo scopo, come ho gia' detto, e' quello di avere la stessa qualita' video ma usando meno MB. Questo perche' oramai tutto si condivide su internet e piu' compatto e' il video piu' facilmente lo si condivide.
Il miglioramento non sta' nella qualita' assoluta del video, ma nella qualita' relativa. Ovvero, se un codec mi permette di ottenere un video con la stessa qualita', ma che occupa meno MB, significa anche che mi permette di creare un video che, a parita' di MB, e' migliore.
Guarda Youtube, la maggior parte dei video sono inguardabili. E perche'? Perche' sono stati compressi esageratamente al fine di ridurre i MB. Un codec migliore potrebbe permetterti di creare un video che occupa gli stessi MB ma meno degradato.
In questo caso la differenza di qualita' la vedi.
Ciao! |
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mda
Dio maturo
Registrato: 01/11/06 09:39
Messaggi: 6648
Residenza: Figonia
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| Inviato: 03 Ott 2009 18:28 Oggetto: |
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| zero ha scritto: |
Lo scopo, come ho gia' detto, e' quello di avere la stessa qualita' video ma usando meno MB. Questo perche' oramai tutto si condivide su internet e piu' compatto e' il video piu' facilmente lo si condivide.
Il miglioramento non sta' nella qualita' assoluta del video, ma nella qualita' relativa. Ovvero, se un codec mi permette di ottenere un video con la stessa qualita', ma che occupa meno MB, significa anche che mi permette di creare un video che, a parita' di MB, e' migliore.
(...)
In questo caso la differenza di qualita' la vedi.
Ciao! |
Si visto è giusto in questi parametri (la stessa moneta ma due facce), la vediamo da due punti diversi ma è poi la stessa cosa.
Ciao |
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{paolo del bene}
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| Inviato: 07 Ott 2009 20:24 Oggetto: |
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Codec software libero:
per la Free Software Foundation.Inc è l'unica vera e valida alternativa ai codecs software non libero.
avi, wmv, realplayer, mpeg, mv4, .... dunque un ottimo codec e facile da usare.
si segue la sintassi per scompattarlo, si segue passo passo come installarlo e successivamente da shell si digita ./ffmpeg2theora-0. linux32.bin seguito dal nome del filmato con tanto di estensione e poi si batte invio, non mi sembra dunque tutta difficoltà.
saluti e buona conversione in Theora
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Working with Ogg Theora and the video tag Working with Ogg Theora and the video tag
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Submitted by root. on 2009-08-19 12:45 PM. PlayOgg
The Free Software Foundation's Holmes Wilson is just back from Berlin, where he participated in the Ogg Theora book sprint put on by FLOSS Manuals. Here is a broad look at Ogg Theora and how it fits into the push for free formats: where we're winning, what works, and what could be improved.
Translations: العربية(Arabic)
UPDATE: In response to comments on this post I've added an update and FAQ (see below).
Introduction:
Ogg Theora is becoming a big deal, and that's exactly what we hoped for when we launched the PlayOgg campaign in May 2007. The free, patent-unencumbered video codec now works in over 24% of the world's web browsers with no plugins required. The latest 1.1 release of the Theora encoder is coming out any day now. And when it does, the huge improvements in quality and functionality made over the past year with support from Wikimedia and others will percolate out into the major GNU/Linux distributions, arriving at the fingertips of those who build and maintain the world's biggest video sites. Most of all, people are excited, releasing new tools that make the Theora easier to use, as well as jaw-dropping demos of what free formats and web standards can do.
I'm freshly arrived from Berlin, where FLOSSManuals just hosted a book sprint on everything Theora, from politics to playback, encoding, hosting and even streaming--all using free software and web standards. The main goal of the trip was to get an idea of where Theora is at: what's working well, what's still difficult, and the best ways to push adoption forward (both by organizing people and by making easier-to-use tools). Overall, I think we're close to something that can work for large numbers of people watching and publishing video, though there are still some tricky bits and sacrifices that--in an ideal world--you wouldn't have to make. Wherever possible I've linked to the relevant bits in our new Theora manual for anyone who wants to learn more.
Playing Theora videos
For anyone who wants to play a Theora video on their desktop, there's always a simple answer: get VLC (the same answer to the question of how to play almost any format). Since the 1.0 release, VLC has almost 25 million downloads, so lots of people already have it. For GNU/Linux users, Theora playback should be included with almost every distribution. And of course, you can also just open the file with Icecat 3.5 or later, or any equivalent Gecko-based browser.
Video quality
Don't believe the FUD: the quality of Theora-encoded video for a given bitrate is excellent. While there are some reasons to consider h.264 to be technically superior, the difference for web-quality video just isn't noticeable. See for yourself, here and here.
Theora isn't ideal yet for HD video (something about the motion vector being too small) but the consensus was that this is very fixable. Also, for web video publishing, you can use a tool like Firefogg to go straight from your original video (in any format) to the smaller web version-- instead of transcoding once before upload and again on the site (like you would while publishing to sites like Dailymotion, Youtube, Vimeo or Blip.tv)
Video hosts
Most video publishers just want a place to put their video where they don't have to worry about formats, bandwidth, and hosting. And while Youtube doesn't support Ogg Theora yet, there are several smaller sites that do. See the Hosting Sites section in the Theora manual for an overview, or here's a quick list:
* Tinyvid - a simple video site with a Java-based fallback for non-Theora-capable browsers.
* Dailymotion - A huge video sharing site with Theora support (see: Theora support is a big deal).
* Archive.org - Encodes your video to various formats (including Theora) and stores it forever.
* Wikimedia Commons - Wikipedia's growing multimedia infrastructure.
So if you're looking for a quick way to post videos for distribution in Theora, there are some great options to choose from. Unfortunately, with the exception of Dailymotion, most of these sites do not have the large built-in audience or the advanced rating / sharing features of a site like Youtube. As advocates for free formats, we need to figure out how to push more large video sharing communities like Youtube to take the plunge (as Dailymotion already has) and offer videos in Theora.
Putting videos on your own site.
Now that HTML5 and Theora support in browsers has made video a "first class citizen of the web", it's easier than ever to post a video to your own site without relying on a middleman like Youtube. The Theora Cookbook includes an excellent overview of how to post videos using HTML5 and Theora. You can upload and display videos on your site just like images or HTML pages, but there are a few tricky parts:
Tricky part #1: Mimetypes.
Since the video tag is a new thing, your web host might not set the mime types correctly. One of the Theora developers at the event told me that, when somebody comes on the Theora IRC channel and says "Hey, I just posted a video and it doesn't work!" it's almost always a problem with mime types and headers. If your host isn't setting the mime types right, you either need to edit your .htaccess file or (if that's off limits) offer the videos using a PHP script. The Hosting Theora Yourself chapter describes both of these solutions in detail.
Tricky part #2: Allowing remote access or direct linking
Remember how sites used to (or sometimes still) get irritated when people link directly to their images? For better or worse, the HTML5 video spec defines a way to prevent this. So if you want people to be able to link directly to videos on your site, you need to enable it. See here for how to do this for all sites, or for specific sites.
Tricky part #3: Fallbacks for non-compatible browsers
Even before several browsers supported Theora natively, the free software community had a reliable (if slightly non-ideal) way to play Theora videos in the browser: the Cortado java applet. Now, Cortado is handy as a way to let all those weird IE and Safari users (at least the vast majority of them who have Java installed) watch the Theora videos you post to your site. The HTML5 Video chapter in the manual explains how to automatically fallback to Cortado for non-compatible browsers, and it includes sample code. The one major drawback of Cortado, which seems unavoidable, is the long loading time--your viewers will spend a good several seconds watching the Java teacup logo wondering why the video isn't playing. When using a Cortado fallback, it's probably best to include a link recommending a Theora-capable browser.
Making it easy for others to upload Theora.
If you're running a video host or some kind of community video site, you will need a way for people to upload Theora without necessarily knowing what Theora is. The standard way to do this is to allow uploads in any format and then transcode them all (like Youtube et al). The ffmpeg2theora tool will convert practically any video under the sun to a Theora video with the quality, bitrate, and other characteristics desired. Check out the ffmpeg2theora chapter in the manual for more on how to use it.
Firefogg--a browser extension for transcoding and uploading Theora videos--is another way to address the transcoding problem, and it has some unique advantages. Once users have installed Firefogg in their browser, sites can call it in their upload form. When users select a file, Firefogg will convert it to Theora as part of the upload process. With some extra configuration on the server side, Firefogg can even upload pieces of the file as it's doing the conversion to save time. Firefogg will also ensure that, if the connection goes down, the upload will resume as soon as the connection comes back.
Firefogg brings two important advantages. First, sites (or web applications like Wordpress) could rely on Firefogg instead of having to develop a transcoding system on the server side. Second, the video quality can be better, because the video only gets converted once (instead of twice-- once before upload, and once on the hosting site). The main disadvantage of Firefogg is that users need to install a browser extension. But perhaps someday Icecat itself could include this feature.
Conclusions
The push for free video formats is at an important moment: the necessary parts of an online video space based on free formats are in place, and it's all a matter of how we use them (and who uses them). Theora playback now has a mass user base: tons of people use VLC, and orders of magnitude more people use Gecko-based browsers. Anyone who wants to distribute their video on the web in a free format can upload it to Dailymotion, Tinyvid, or the Video Bay with minimal hassle. With Cortado, we have a fallback for people with older or non-compatible browsers that doesn't require non-free software or non-free formats. HTML5 and the video tag give developers new ways to manipulate video on the fly, setting the stage for entirely new kinds of interaction around video.
To me, the missing pieces seem to be in video publishing and general awareness. Specifically, we need:
More Theora support from video hosting sites So far, only one large video host supports Theora. The free software community needs to find effective ways to push Youtube, Facebook, Blip, Vimeo (as well as the large video advertising services) to run pilot projects and move towards full HTML5/Theora support.
A Theora upload plugin for popular free software publishing platforms If you could upload any video to web publishing systems like Wordpress using Firefogg, and automatically present it with a Cortado fallback, this would dramatically reduce the number of steps required to post a Theora video on your own site.
Effective evangelism We need organized ways that people can convince the sites they like to publish in free formats. We also need ways for sites that use free formats to declare their support for the cause, and make the social mission behind their decision visible to users.
The FSF will be working on all these angles and more as part of its PlayOgg campaign. If you'd like to help out, get on playogg-discuss. Or if you have any specific comments on this article, email me at holmes at fsf dot org. Finally, anyone looking to become an expert on Theora should check out FLOSS Manuals' Theora Cookbook. The event was a great experience and the end result is solid. If you like it, buy a copy!
Update and FAQ
This article spurred some excellent discussion on Digg, so I thought I'd include the highlights, and some of my responses in a mini-FAQ:
What about hardware acceleration for improved battery life on mobile devices?
Theora doesn't have that yet, but if it becomes a popular way to post videos to the web, it could happen soon. In the meantime I'm okay with putting a bigger battery in my phone to be able to watch videos in formats other than h.264.
Most of the cheap "MP4" players (aka the iPod of the developing world) now support the free audio format Ogg Vorbis. They don't even advertise it, but the one manufacturer that makes all the chips simply included Ogg Vorbis support. Hardware support will probably happen, it just takes a little while.
What about Dirac?
There are other important projects with similar goals, like Dirac, an effort spearheaded by the BBC. But the exciting thing about Theora is that it's here now, supported by popular tools, and ready for mass adoption.
We expect Ogg Theora to have its strength in online video distribution, whereas Dirac will most likely have its strength in high definition footage.
Didn't Google just buy a more advanced codec that it's going to offer as a free format?
That would be awesome, but it's not a good idea to base a free formats strategy on what Google might do.
Advocates for free formats aren't trying to privilege Theora over other free video formats. We're just trying to get a foothold with something that we have now, and that works now. If some better patent unencumbered format comes along, we'll rush to include that under the umbrella.
Dailymotion's support for Ogg is a big deal Dailymotion's support for Ogg is a big deal
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Submitted by root. on 2009-08-11 05:14 PM. Community
With video streaming site Dailymotion offering the free Ogg Theora video format, FSF urges other video sites to follow.
Dailymotion has transcoded over 300,000 videos to the free Ogg Theora format, which will play without the need for plugins in the latest free software web browsers. Dailymotion is among the world's largest video streaming sites, making this a major advance for Ogg Theora format,
The Free Software Foundation and its PlayOgg campaign welcomed the news, "A creative art such as video production that is dominated by proprietary software can limit freedom of expression," said FSF executive director Peter Brown, "Dailymotion's support for Ogg Theora will let videomakers reach a large audience without compromise or concern for their software freedom."
?Our users expect the best possible experience and we are excited to be supporting free software and standards,? said Sebastien Adgnot, lead developer of Dailymotion's new Theora-driven portal.
"This is a milestone for free standards and free formats," continued Brown, "Dailymotion has taken a strong stand in support of Ogg Theora, and they've demonstrated that you can deploy Theora video on a mass scale."
Theora ready for primetime
With the release of the new HTML5 specification and its support in new versions of popular web browsers, Ogg Theora is easier than ever to use. Over 22% of users have browsers that will play Theora, and video publishers can use Java-based fall-backs like the free software player Cortado to support the browsers that still lack built-in Theora support. It's hard to overstate the importance of this step by Dailymotion. But it's also part of a broad movement by video makers, web developers, and online video companies toward independence from proprietary software and non-free formats, a movement in which supporters of the FSF and its PlayOgg campaign have played--and will continue to play--a vital role.
Beyond Flash
One of the most exciting recent developments for free software in the online video realm is the "video tag." This new HTML5 standard lets web developers build new ways of interacting with video without the need for proprietary software like Flash (Gnash is great after all, but you shouldn't need a plugin to play a video). The video tag provides web developer flexibility such as the ability to control and modify videos on the fly using web standards like JavaScript and cascading style sheets (CSS).
Ahead of Youtube
Dailymotion has a history of supporting the free software community, and now they're the first major video sharing site to implement significant support for Theora (here's a full list). With their support for free video standards, Dailymotion has jumped ahead of industry giant YouTube. Google's recent purchase of On2 - the company behind many advanced proprietary video codecs - gives Google an opportunity to help the free software community by freely licensing additional codecs. But until that happens (and it may be far off) Youtube will depend on non-free formats like h264 and proprietary software like Flash--while Dailymotion lets you publish using free formats right now.
Novembre 12th, 2008
by Sandy Kirchlechner
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Rilasciato PlayOgg Theora 1.0
Logo Xiph.OrgLa Xiph.Org Foundation ha annunciato il rilascio di Theora 1.0. Video codec libero, un?ottima soluzione per artisti, produttori e sviluppatori che vogliono contribuire a creare un mondo più libero. Theora è stato standardizzato nel 2004, ma questa versione matura e stabile è un passo importante per il programma.
Le prossime release di Mozilla Firefox supporteranno Theora out of the box con il nuovo elemento HTML5 , il che significa che anche tutti gli altri web browser liberi derivati dal codice sorgente di Firefox, come Iceweasel e GNU IceCat, sapranno fare lo stesso.
Congratulazioni a Xiph.Org! |
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