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LCWO Discussion Forum [Atom LCWO Forum Feed]

This is a simple discussion forum for LCWO users. Feel free to use it for any kind of discussion related to this website.

Thread: New: Native HTML5 audio support!

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Posted: 2010-05-15 21:00

What is HTML5?

Quote: http://en.wikipedia.org/wiki/HTML5
HTML5 is being developed as the next major revision of HTML (HyperText Markup Language), the core markup language of the World Wide Web. HTML5 is the proposed next standard for HTML 4.01, XHTML 1.0 and DOM Level 2 HTML. It aims to reduce the need for proprietary plug-in-based rich internet application (RIA) technologies such as Adobe Flash, Microsoft Silverlight, and Sun JavaFX.[emphasis added]

As of today, LCWO experimentally supports HTML5! If you go to your CW settings, you'll find a new player option, called "HTML5 player". When activated, your browser takes care of the Morse playback itself, without using a third party plugin like the Adobe Flash player which is currently used by almost 99% of the LCWO users.


HTML5 or a subset thereof is supported by most of the major browsers, namely Firefox (3.5 and later versions), Google Chrome (3+), Safari and the latest beta of Opera. Internet Explorer 8 does not support HTML5, I don't know about IE9.

These browsers which support the required HTML5 audio-tag do not all support the same codecs, which makes it a little more difficult to offer a solution which works with every one of them. Firefox, arguably the most popular browser except the IE, supports the free OGG audio formats, but not MP3 (because of restrictions due to patents). Google Chrome seems to support both MP3 and OGG, Opera at least supports OGG.

The software which generates the CW sound files for LCWO only supported MP3, so it was neccessary to add an encoder for the OGG/Vorbis format. This has been accomplished today. The OGG format is now the default for the HTML5 player.

In theory, all browsers with sufficient HTML5 support should work together with LCWO now. My own testing confirms that Firefox 3.6 works very well; Google Chrome seems to have some problems with the playback. This will be investigated as soon as possible.


More Freedom: The Flash plugin is not natively available for all platforms (e.g. FreeBSD, for the iPad). Where it is available, it's a proprietary piece of software which bears the usual risks of security problems and privacy issues.

Stability: The old flash plugin appeared to cause a lot of crashes on some systems. It can be hoped for a more stable operation of the audio playback with the browser does completely natively.

Speed: Especially on older computers and e.g. netbooks with little memory and CPU power the old plugins caused unneccessary load. For mobile devices, this directly shortens the battery life time!

Of course it will take a while until HTML5 is universally supported. About half the users of LCWO use the Internet Explorer, many of them (why, oh why?) old versions like IE6. The HTML5 standard is also not finally fixed yet, so there may be little changes here and there. But I want to start employing and testing it on LCWO as early as possible.


I am sure there will be plenty of issues at the beginning. Please feel free to report any problems with the new HTML5 player here in this thread. For now, my main interest is to make it work perfectly with Firefox 3.5/3.6, but any feedback is appreciated.

73, Fabian DJ1YFK

Posted: 2010-05-15 21:40
Hi Fabian, works fine so far, but at least on my system (FF 3.6.3, latest Flash player) the volume is only on/off switchable - i.e., the volume fader can not be set to different positions, because it disappears if you move the mouse away from the loudspeaker symbol to adjust volume. But anyway, nice feature! Sounds good, too :-)

73, Jan

Posted: 2010-05-15 21:46
Indeed, never tried it. Probably doesn't happen if the player is used for videos and its vertical size is higher.

But you can change the volume with the up/down cursor keys.

Just checking the Firefox BugZilla database for this problem.

Edit: Seems to be a known bug: https://bugzilla.mozilla.org/show_bug.cgi?id=533201


Posted: 2010-05-16 04:51
Works fine with Firefox on Macintosh.
Did not work Google Chrome 5.0.375.38 beta for Mac.
Thank you for a great site. I will test these again when Chrome gets out of beta.

Posted: 2010-05-16 17:09

I haven't changed a thing on this end and noticed that now when I do a 25 call sign practice run that there are one or two characters at the beginning of a call sign that has a fade in flutter to it. It is not crisp as all of the other characters. It now causes me to have an error on the first character of those call signs.

Craig, AH8DX

Posted: 2010-05-16 17:12
Still doing some "fine tuning" of several parameters (both for the new HTML5 player and the old FLash player). I changed it towards a little more conservative values now. Please let me know if the problems persist or disappeared.

73, Fabian

Posted: 2010-05-16 17:33


Posted: 2010-05-16 17:51

American proverb :"Never change a winning horse" became "Ever change a winning horse"

NU2E? Now Underway To Eternity?

You did not change a thing at your end? Change your call back to AH8DX and your problem may be solved!

Posted: 2010-05-16 18:03
Interesting change of the proverb :-)

OK, I adjusted it to almost the old value again and I booted the other PC which uses Flash 10, and it seems to be better now.

Also, still fighting with Opera and HTML5, but that is a whole different story.


Posted: 2010-05-16 18:45
Mr. 16818-1-16817

I am the proud owner of both calls.

Have a great day.

Craig, AH8DX,NU2E

Posted: 2010-05-16 19:31

Mr. 16818-1-16817 is Mr Zero, did you notice that?

You are not working and proceeding as hard as I do. You have obviously reached your ceiling, because your score increases slowly but not so your speed.

BTW I am the proud owner of number 16818. In numerology it is a very important number yet higher in rank then 666.

Posted: 2010-05-16 19:49
Dr. Faust,

American proverb: "I have just begun".

Setting all jokes and harassment aside, I want to thank you for the encouragement for me to work even harder. You are right, I have had a recent setback with my health and I have not proceeded ahead as I had planned but your words this morning have given me new life and I will try to get back on track soon.

I am making progress but it is slow. Please pay attention to the new RufzXP Toplist on Monday as I have submitted a NEW PERSONAL BEST.

Have a great day and thanks for the encouragement to keep working harder than ever on my cw.

BTW, I needed to get another call as my current call is a terrible contest call on cw, therefore, I selected NU2E as a contest call.


Craig, AH8DX/NU2E

Posted: 2010-05-16 20:00
I knew that's the way to boost your performance.

Next monday night I will take a look at NU2E, a call easy to remember now, at RUFZXP

Looking in the left most column, thats where I expect you to be.

Posted: 2010-05-16 20:07
I haven't done any under my new club call (NU2E), so please still look for my new score under AH8DX; I don't think I am to that left column yet but it will come soon as I am not too far away now.


Posted: 2010-05-17 03:46
Just as a data point, HTML5 doesn't seem to work under Safari (Mac OS X 10.6.3)

Posted: 2010-05-17 08:56
Thanks, Jim. As expected: Safari only supports MP3 for the HTML5 audio tag, LCWO (currently) only delivers OGG files. But as you see, it's a work in progress. It'll be available soon.

Over the weekend I spent a lot of time with Opera and Google Chrome, but without satisfying results so far:

The latest build of Opera (10.53b or so) generally works, but in the Callsign/Word training modes, there seems to be a race condition between loading the new file and playing it.

Google Chrome completely refuses to play any MP3 or OGG files that are generated on the fly by my CGIs. And I have no idea why...

It doesn't get boring on the HTM5 front :-)

73, Fabian

Posted: 2010-05-17 18:01
html5 works perfect with firefox 3.6 on windows xp


Posted: 2010-05-18 02:35
Works Excellent on OS X 10.6 using Firefox 3.6.4

Got rid of the annoying audio glitches at the beginning of a code segment.

Keep up the great work.

73 Bob WV7W

Posted: 2010-05-18 22:29
Usually works great on 64bit Ubuntu 10.04 and Firefox 3.6.3. Sometimes tough it just stops in the middle of a code run, not reaching the 4 minutes I currently work with.

On 32bit Arch Linux with Firefox 3.6.3 there is a loud cracking sound mixed in with the code segments that seems to be louder at the beginning of a segment!

What does not work anywhere is the progress bar, but that does not really work that great in Flash as well.

73 Andi, OE4DNS

Edited to describe further trials!

Posted: 2010-05-19 07:31
Hi Andi,

thanks. The progress bar doesn't work here either, I suppose it's because the file is not fully loaded while the playback already is running, and there is no way to estimate the full time.
I also noticed that the generation of the OGG files for the HTML5 player takes a lot longer (up to 5 times) on the server than the MP3 files (I chose variable bit rate for the former, fixed for the latter, that may be the reason), so there might sometimes be a race condition when the server doesn't deliver the file as fast as the playback is running.

I observed the cracking sound with Google Chrome only so far, when playing "static" OGG files via HTML5. It seems to occur with sound files of low sample rates only.

Did some more experiments with Opera last night but without any success. Also tested Safari on Windows, but (contrary to the OSX version) it doesn't seem to have support for the audio-tag yet.

Well, as you see, it's all still very experimental but I am confident to get it running properly in the future...

73, Fabian DJ1YFK

Posted: 2010-05-20 17:12
Hallo Fabian
Unter Linux FF 3.6.3 knackt / unterbricht die HTML5-Ausgabe recht häufig. Habe wieder auf den Flash Player V10 umgestellt, der funktioniert einwandfrei.

73 Werner, HB9SWR

Posted: 2010-05-22 12:55
Hi Fabian
FYI html5 on Opensuse 11.2 with firefox 3.6.3 suffers from the crackling noise interference too
Flash 10 OK tho'


Posted: 2010-06-06 15:23
Hello, thank you for the very helpful website. It works great with the newest Firefox on os 10.5. I just tried to use the site with an iPad and the HTML 5 audio does not seem to be working. Please let me know if I can be any help testing.
Patrick KC2RBE

Posted: 2010-06-27 17:08
In Firefox/Linux the sound is not good (flicks, the current indication is not corect).

Posted: 2010-06-30 06:12
everything works fine on FF 3.6.3 on Ubuntu machine :)

the volume slide bar did not seem to work, but then discovered this tip:

hover the mouse on the bar which you want to change and then use the keyboard's arrow keys to change the bar (don't use the mouse)!

Posted: 2010-07-16 04:07
FYI, the link at the top of the site is broken - it's pointing to t=23, but this thread is t=372 !

Posted: 2010-07-16 07:46
Oops. Fixed. Thanks.

Posted: 2010-07-17 08:55
Pitch seems different in html5 and flash10.



Posted: 2010-07-18 23:13
Mh, tried HTML5 and Flash in two browsers, side by side, and it sounds the same in both.

In which training mode did you notice a difference?

73, Fabian

Posted: 2010-07-19 21:55

absolutelly nothing to worry about, the pitch difference is an estimated quarter to half tone.

On Firefox 3.6.6, I go to "Change CW settings".
Then I choose flash 10, submit, then play the test sequence (VVV...) on the bottom of same page.

Then Ichange to HTML, submit and play test sequence.

Funny enough when changing from HTML to Flash10 firefox complains about Flash not installed (wrong), so sequence to change back is select Flash10 player, submit, reload, play test sequence.

I found it interesting that both players do not play exactly the same pitch, just wanted to mention that. But really it's a non-issue.



Posted: 2010-07-19 22:16
> Funny enough when changing from HTML to Flash10
> firefox complains about Flash not installed
> (wrong), so sequence to change back is select
> Flash10 player, submit, reload, play test
> sequence.

Fixed that. A short while ago I removed loading all the JavaScript stuff needed to include the Flash player if HTML5 was used. When changing from HTML5 to Flash, at the point where the stuff is loaded, the old settings are still in effect, so it appears that you don't have Flash installed. Now works.

Still, here at my side (Firefox 3.6.6 or Chrome on Linux with PulseAudio), there is not even the slightest difference in pitch. I suppose that depending on the sound system used, some re-sampling to a different rate may take place, which causes this problem.

But indeed, if it's just a half tone, there is nothing to worry about :-)

73, Fabian

Posted: 2010-08-03 19:39
HTML5 was working fine up to Firefox 3.6.6 or 3.6.7 but now with 3.6.8 there are intermittent pops in the audio which seem to reflect extremely brief pauses. This is occuring on a Vista 64 laptop and a WinXP netbook.

Posted: 2010-08-08 12:09
I have found same problem as ae5ka.I use firefox 3.6.3 and linux (slackware 13.1).

Posted: 2010-08-11 08:41
Thanks for all the info. The implementation of the HTML5 capabilities still seems to be changing from version to version. I hope it'll stabilize before long :-)
For the next steps, I plan to evaluate other browsers than Firefox and their HTML5 capabilities.

In the meantime, one of the Flash players still seems to be the best option for most.


Posted: 2010-08-11 13:42
I'm having problems with both the flash players - not with the audio but with the widget. The slider in the time bar does not move, this means you can't select where you want to go back to when listening again to check.

I'm running Firefox 3.6.8 on Ubuntu 9.10 Karmic with a Gnome desktop

Posted: 2010-08-11 22:22
My experience with opera 10.60, HTML5 and linux (gentoo) (Koch lessons):
start of sound is generally chopped, that is first character is choppy.
From time to other the file will end early (40 secs of 1 minute) causing a lower correct rate :(

Otherwise a good idea to support HTML5 so we can finally get flash out of the web.

Posted: 2010-09-28 20:19
HTML5 should now also work for Apple Safari, where a MP3 instead of a OGG file is served.

Safari users, please test it; I can't do it myself.

Tnx & 73
Fabian DJ1YFK

Posted: 2010-10-01 05:52
Hi Fabian,
Thanks for all the effort you've put into enabling Apple addicts to use lcwo.net. I can report that using the HTML5 player setting on lcwo.net appears to work on both an iPhone 3G and a new iPhone 4. The cursor neatly jumps to the text input field ready for you to key in the code. Same success with the iPad which is excellent as the keyboard - on screen or outboard - is much more practical.
So lcwo.net now appears to work with both iOS 3 & 4
Thanks so much for enabling this!
73 Stephen VK2RH

Posted: 2010-10-01 18:53
Thanks for your report and the post on your blog, Stephen!

73 and have a nice weekend!
Fabian DJ1YFK

Posted: 2010-10-06 13:36
I echo the thanks for the HTML5 support ... works great on my iPhone. Now I can practice anywhere :)

Jonathan G0DVJ

Posted: 2010-10-07 17:22
Works on IPad too! Fantastic

Posted: 2010-10-28 11:38
Using OS MacOS X 10.6.4 and Safari 5.0.2, HTM5 does not work in Morse Machine, though it does on the Configure and Koch Lesson pages. On the Morse Machine it's just silent, but it obviously thinks it has played something, as it highlights random letters in red any time you press a key (unless you get lucky)...

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