theora - Mar 2010 - recommendations for web video bit rates

Hey, everyone.  I'm sure this thread will generate some email!

Some people are working on a super-easy to use converter for people to 
be able to convert videos to Theora for the upcoming Get Video on 
Wikipedia push:

http://videoonwikipedia.org/

(Note that this isn't being pushed yet, and is pre-launch quality!)

For the converter one thing we'd like to be able to provide is a set of 
profiles for quality, bitrates and sizes that people can use to generate 
Theora videos.  (Michael Dale wants this for Firefogg, too.)

The number of bits that you need to allocate depends highly on the 
content - everyone here knows that - but we can come up with a rough set 
of guidelines that give a rough estimate for low/medium/high for a given 
size.  (Is it a linear scale, depending on width * height?)

I think that people have done this before, but just looking for 
experience and guidance.

--Chris

On Sat, Mar 13, 2010 at 4:11 PM, Christopher Blizzard
<blizzard at mozilla.com> wrote:
> Some people are working on a super-easy to use converter for people to
> be able to convert videos to Theora for the upcoming Get Video on
> Wikipedia push:
>
> http://videoonwikipedia.org/
>
> For the converter one thing we'd like to be able to provide is a set of
> profiles for quality, bitrates and sizes that people can use to generate
> Theora videos. ?(Michael Dale wants this for Firefogg, too.)
>
> The number of bits that you need to allocate depends highly on the
> content - everyone here knows that - but we can come up with a rough set
> of guidelines that give a rough estimate for low/medium/high for a given
> size. ?(Is it a linear scale, depending on width * height?)
It would be good to have at least one resolution/bitrate that decodes
well on mobile web browsers that support Theora (I think that's just
Firefox, but I could be wrong).  If this use case isn't specifically
targeted, it's possible that none of the selected quality levels will
play smoothly on mobile devices (or none will do so reliably).  This
would be a major impediment to Theora/Wikipedia's perceived usefulness
or competitiveness with H.264: "Why can I play YouTube on an iPhone,
but I can't play Wikipedia videos on an N900?"

Since Theora doesn't specify profiles like H.264 does, it's important
to do some testing of our own to find a particular resolution/bitrate
of Theora that most devices with a Theora-capable browser can handle.
This could be done at least with Firefox on the N900 and whichever
Firefox pre-release is available for Android (using whichever
"minimum" hardware it will support).

I'm willing to try out some videos on my N900 if someone can give me a
few to try.  I'm guessing there are others on this list that have an
N900 to try so perhaps we could split up the test cases between
multiple people.

Denver
http://ossguy.com/

This is what i am looking for too.

On Mar 13, 2010 3:11 PM, "Christopher Blizzard" <blizzard at
mozilla.com>
wrote:

Hey, everyone.  I'm sure this thread will generate some email!

Some people are working on a super-easy to use converter for people to
be able to convert videos to Theora for the upcoming Get Video on
Wikipedia push:

http://videoonwikipedia.org/

(Note that this isn't being pushed yet, and is pre-launch quality!)

For the converter one thing we'd like to be able to provide is a set of
profiles for quality, bitrates and sizes that people can use to generate
Theora videos.  (Michael Dale wants this for Firefogg, too.)

The number of bits that you need to allocate depends highly on the
content - everyone here knows that - but we can come up with a rough set
of guidelines that give a rough estimate for low/medium/high for a given
size.  (Is it a linear scale, depending on width * height?)

I think that people have done this before, but just looking for
experience and guidance.

--Chris
_______________________________________________
theora mailing list
theora at xiph.org
http://lists.xiph.org/mailman/listinfo/theora
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On 03/13/2010 04:11 PM, Christopher Blizzard wrote:
> Hey, everyone.  I'm sure this thread will generate some email!
>
> Some people are working on a super-easy to use converter for people to 
> be able to convert videos to Theora for the upcoming Get Video on 
> Wikipedia push:
>
> http://videoonwikipedia.org/
>
> (Note that this isn't being pushed yet, and is pre-launch quality!)
>
> For the converter one thing we'd like to be able to provide is a set of
> profiles for quality, bitrates and sizes that people can use to generate 
> Theora videos.  (Michael Dale wants this for Firefogg, too.)
>
> The number of bits that you need to allocate depends highly on the 
> content - everyone here knows that - but we can come up with a rough set 
> of guidelines that give a rough estimate for low/medium/high for a given 
> size.  (Is it a linear scale, depending on width * height?)
>
> I think that people have done this before, but just looking for 
> experience and guidance.
>
> --Chris
> _______________________________________________
> theora mailing list
> theora at xiph.org
> http://lists.xiph.org/mailman/listinfo/theora
>   
Chris,

The only foray into streaming/online video I've done is at the following
link:

http://a2a.haylstorm.com/

Those vids are 640x480x15fps, and their rate is actually vbr based on
the quality 10 setting.  But the videos are also heavily post-processed
and they didn't have much change either.

The rate for the Theora stream in each file ranges from 270 - 537kbps,
and the audio for each is around 70 kbps (mono).

So far I have not received any complaints from people visiting the
website, so I must presume they generally are not experiencing buffering
problems.

You might also consider looking at the "profiles" that ffmpeg2theora
supports.  I'm not sure how rigorously those presets were chosen, but
it's something to start with.

-- 
      Basil Mohamed Gohar
abu_hurayrah at hidayahonline.org
http://www.basilgohar.com/blog
basilgohar on irc.freenode.net
GPG Key Fingerprint:  5AF4B362

>Basil Mohamed Gohar abu_hurayrah at hidayahonline.org
>Sat Mar 13 16:13:01 PST 2010
>You might also consider looking at the "profiles" that
ffmpeg2theora
>supports.  I'm not sure how rigorously those presets were chosen, but
>it's something to start with.
here are the ffmpeg2theora presets:
"
v2v presets:
  preview        Video: 320x240 if fps ~ 30, 384x288 otherwise
                        Quality 6
                 Audio: Max 2 channels - Quality 1

  pro            Video: 720x480 if fps ~ 30, 720x576 otherwise
                        Quality 8
                 Audio: Max 2 channels - Quality 3

  videobin       Video: 512x288 for 16:9 material, 448x336 for 4:3 material
                        Bitrate 600kbs
                 Audio: Max 2 channels - Quality 3

  padma          Video: 640x360 for 16:9 material, 640x480 for 4:3 material
                        Quality 6
                 Audio: Max 2 channels - Quality 3

  padma-stream   Video: 128x72 for 16:9 material, 128x96 for 4:3 material
                 Audio: mono quality -1
"
What about supporting the VCD/DVD/SDTV sizes?
Has anyone looked at the preset on http://firefogg.org/make/index.html ?

tom_a_sparks

Hi,

Some time ago i made some encoding test with those settings:
"lq":"--no-upscaling -V 164 -A 32 -c 1 -H 22050 --max_size 200 -F
15",
"web":"--no-upscaling -V 544 -A 96 -c 2 -H 44100 --max_size
400",
"hq":"--no-upscaling -v 6 -a 3 --max_size 1080",

results here: http://firefogg.org/j/encoding_samples/

if we can come up with some good presets i am happy to add those to
ffmpeg2theora -p


j

> Some people are working on a super-easy to use converter for people to
> 
> be able to convert videos to Theora for the upcoming Get Video on 
> Wikipedia push:
> 
> http://videoonwikipedia.org/
Great to see there's going to be a push to get more Theora video on
Wikipedia!

This makes me wonder:
Is there a vendor-neutral site for promoting Theora-playback in browsers?
PlayOgg.org seems to be about promoting VLC--not in-browser Ogg playing.

I'd like to see a promo site that authors could point users who don't
have HTML5/Theora capable browsers to while still respecting the browser choices
the users have already made and without the authors having to maintain browser
advice themselves. That is, if the user came to the promo site with a pre-3.5
version of Firefox, the site would show operating system-relevant instructions
for upgrading to a Theora-capable version of Firefox. Similarly, users of old
Chrome or Opera releases would be instructed to upgrade to new Chrome or Opera.
Safari and Epiphany-WebKit users would be instructed to install a Theora
decoder. IE users would get a browser ballot-like choice of Firefox, Opera and
Chrome. iPhone users would have to get a message explaining why they can't
play Ogg.
> (Note that this isn't being pushed yet, and is pre-launch quality!)
> 
> For the converter one thing we'd like to be able to provide is a set
> of 
> profiles for quality, bitrates and sizes that people can use to
> generate 
> Theora videos.  (Michael Dale wants this for Firefogg, too.)
It would be really nice to have reasonably tuned presets for XiphQT, too.
(QuickTime's dialog limitations permitting, of course.)

-- 
Henri Sivonen
hsivonen at iki.fi
http://hsivonen.iki.fi/

On 3/14/2010 5:57 AM, j at v2v.cc wrote:
> Hi,
>
> Some time ago i made some encoding test with those settings:
> "lq":"--no-upscaling -V 164 -A 32 -c 1 -H 22050 --max_size
200 -F 15",
> "web":"--no-upscaling -V 544 -A 96 -c 2 -H 44100 --max_size
400",
> "hq":"--no-upscaling -v 6 -a 3 --max_size 1080",
>
> results here: http://firefogg.org/j/encoding_samples/
>
> if we can come up with some good presets i am happy to add those to
> ffmpeg2theora -p
>
>    
Hey, so this and the table from Tom help a lot.  One last question - do 
we a rough mapping for how quality mappings map to bitrates for a given 
size?  Anyone sat down and figured that out with some reference (or 
random!) clips?

--Chris