Embed audio within content/play text as audio

[GoogleCodeExporter]

Could audio files be added to the media that is capable of being embedded 
within explorations? Possible issues might include difficulty in 
hosting/streaming the audio, but I assume that if video is able to be embedded, 
audio could soon follow?

An alternative (and I hesitate showing my technical ignorance by suggesting 
this) would be to create a setting within an exploration to allow the text of 
the content to be read within the browser by default. I'm not familiar enough 
with the technical details of this feature to know whether or not that is 
possible, but I can imagine teachers would love the ability to create math or 
science explorations that do not require high-level readers.

Original issue reported on code.google.com by cory.roush@gmail.com on 1 Apr 2014 at 7:40

[GoogleCodeExporter]

I think it should be possible to create an interactive widget allowing the 
embedding of an audio file. However, if the ultimate aim is to play the text of 
an exploration as audio by default, this is probably not the best solution, 
because it would be tedious to record audio files for every bit of text in an 
exploration (and, furthermore, when a couple of words are changed, the audio 
files would need to be re-recorded, which is going to make maintenance rather 
tedious).

I'm not sure how, or whether it's even possible, to implement a feature which 
allows certain bits of text to be read on-demand (such as when the user clicks 
a "Read this text" button). However, there is actually a way to have text read 
in the browser by default -- the caveat is that it reads more or less 
everything on the page. It is used in screen readers for visually impaired 
users. This is how to use it:

1. Open the Chrome browser.
2. Download and enable the ChromeVox extension: 
https://chrome.google.com/webstore/detail/kgejglhpjiefppelpmljglcjbhoiplfn
3. Download and enable the US English Female Text-to-speech extension: 
https://chrome.google.com/webstore/detail/us-english-female-text-to/pkidpnnapnfg
jhfhkpmjpbckkbaodldb
4. Navigate to any page in your browser, such as a page containing an Oppia 
exploration. The text of the exploration will now be read out.

My concern with this approach is that it might be a bit heavyweight, but if you 
have time, it would be useful to hear what you think about it!

Original comment by s...@seanlip.org on 6 Apr 2014 at 7:01

[GoogleCodeExporter]

Original comment by s...@seanlip.org on 14 Dec 2014 at 12:26

[GoogleCodeExporter]

I have just received another request for a non-interactive widget that allows 
the upload of audio files (in a similar manner to our upload of pictures), as 
suggested in the first paragraph of this issue.

Original comment by jacobdav...@gmail.com on 27 Dec 2014 at 1:38

[GoogleCodeExporter]

I did a little bit of research, and have a couple of questions for Cory, John 
and Niall:

  (a) typically, how big are your files? Can you attach samples?
  (b) what format are they in? Is it ok if we support only mp3?

The reason I ask is because I was thinking that a good way to approach this is:

  (i)   create a new 'audio' noninteractive widget
  (ii)  allow upload of mp3 files to it; verify that the file is actually an mp3 file before saving
  (iii) play the file using the html5 <audio> tag. The list of supported file types is here, and mp3 seems to be the one with the best coverage:

        https://developer.mozilla.org/en-US/docs/Web/HTML/Supported_media_formats#Browser_compatibility

Also, John, just wondering -- did you get a chance to look into this after our 
last conversation?

Thanks!

Original comment by s...@seanlip.org on 3 Jan 2015 at 2:17

[GoogleCodeExporter]

Been busy with the holidays Sean, but hope to find some time soon.
Had implemented both .ogg and .mp3 on SlideSpeech.
Typical file sizes there are often small, but numerous: 20-50KB for each
interaction

-- 
John Graves
Founder and CEO
SlideSpeech
+64 21 213 8367
Skype: jgraves10514

Auckland
NEW ZEALAND

Original comment by john.gra...@slidespeech.com on 4 Jan 2015 at 5:14

[GoogleCodeExporter]

Mp3 only would be fine. Ogg may also be useful. File size may be much more
than 50kb. You should at least allow for up to 5 Mb ideally more. Your
approach looks fine. Is storage an issue?

Thanks

Original comment by niall.wa...@ucd.ie on 5 Jan 2015 at 9:46

[GoogleCodeExporter]

OK, let's go with mp3 only for now (to keep it simple).

Storage is an issue: we store files in App Engine datastore entries which have 
a maximum size of 1 MB. Do you think you could elaborate on the use case for 
files of size 5 MB++?

Original comment by s...@seanlip.org on 6 Jan 2015 at 2:25

[GoogleCodeExporter]

We have some recordings larger than 1 MB. However, the vast majority are
less than 1MB and I would be happy with that size limitation. Does the 1MB
limit apply to images too?

Thanks

Original comment by niall.wa...@ucd.ie on 6 Jan 2015 at 3:42

[GoogleCodeExporter]

OK, that sounds like we have a working approach. Thanks for the clarification!

Could I ask again about the use case -- i.e., what are these recordings of? I'm 
wondering whether there might be an intrinsic need for large recordings in 
particular subject domains (where they achieve a learning goal that cannot be 
achieved by shorter or downsampled recordings); if so, this would be useful to 
bear in mind.

Also, yes, the same size limit applies to images.

Original comment by s...@seanlip.org on 6 Jan 2015 at 5:08

[GoogleCodeExporter]

Use case: I'm aiming for a "talking Oppia" that would be able to interact
with a marginally literate learner. The recordings thus are mostly short
prompts/conversational snippets.

-- 
John Graves
Founder and CEO
SlideSpeech
+64 21 213 8367
Skype: jgraves10514

Auckland
NEW ZEALAND

Original comment by john.gra...@slidespeech.com on 6 Jan 2015 at 6:10

[GoogleCodeExporter]

use case: higher education - medicine. Existing materials in Storyline have
mp3 audio files up to 2 MB though the vast majority are smaller. (256kb
average audio  file size in one project 545kb in another) I think a limit
of 1 MB will be fine. The much larger file sizes I mentioned previously
were in a different context - not relevant to Oppia

Thanks

Original comment by niall.wa...@ucd.ie on 7 Jan 2015 at 1:01

[GoogleCodeExporter]

+Shantanu (just as an FYI for now)

Original comment by s...@seanlip.org on 4 Feb 2015 at 4:43

[GoogleCodeExporter]

Looks like this was not implemented in latest release (March 2015)

Original comment by niall.wa...@ucd.ie on 17 Mar 2015 at 7:32

[GoogleCodeExporter]

This is correct; sorry about that. We haven't managed to find time to do it 
yet, and are hoping that open source contributors might be able to help.

Original comment by s...@google.com on 17 Mar 2015 at 9:05