Playback issues with xxxx.48k.v2.m4a formats

[Gabriel Testa]

Remi,

Since you guys changed to using xxxx.48k.v2.m4a (from xxxx.64k.m4a), my program hasn't been able to playback any music. I don't know webOS can't handle this format but it keeps giving me a decode error.

I don't know if it has to do with the 48k rate or maybe it's just a naming issue of the file, but for whatever reason, it doesn't work.

This is really bad for me.

Regards,

Gabe Testa

[Joel B]

Hi 8tracks guys,

Fyi 48k is kind of an oddball sample rate to use and is going to cause degradation of audio quality both during the ingestion phase when people upload their files to 8tracks.com, and during playback as it is going to get sample rate converted from 44.1 on ingest and converted again back to 44.1 on playback for most systems.

Better to use 44.1 all the way through your system IMO.

Joel

Sent from my iPhone

[Joel B]

Oops, my bad, that's kilobits! (smacks head)

Sent from my iPhone

On Sep 19, 2011, at 9:03 AM, Gabriel Testa <gabe....@gmail.com> wrote:

[ae]

So the format change appears to have broken Musiclouds as well. That's
more than 15k users who are now unable to use 8tracks on their Roku
:-(

So aside from my stupid remark about sample rates, it appears that the
roku hardware is not capable of playing back the "High Efficiency"
format. Any chance you guys can revert back to the old format? I'm
still testing, but so far, this appears to be the case.

- Joel

[Gabe Testa]

I have 6000 users who can no longer play the audio as well.

-- gabe out

---

[Remi - 8tracks]

Gabe, Joel and others,

I'm really sorry for breaking your apps. We tested the new files on
browsers, flash, android and iPhone but I should have offered sample
files ahead of time to allow you to check it works.

In order to make sure audio plays consistently and that it loads fast
on slower connections, we reencode all files to HE-AAC 44.1kHz mpeg4.

For the past 2 years, we've been using 64kbit / 44.1kHz HE-AAC encoded
with Orban-CT on Windows, we've had 2 ongoing issues with it:
- Android 2.2 and under don't decode properly
- on iPhone, audio quality is terrible.

Because of these issues, we switched to the industry standard HE-AAC
encoder by Fraunhofer:
http://www.iis.fraunhofer.de/en/bf/amm/produkte/audiocodec/audiocodecs/heaac/

We currently store 4+ million files so it's a big job to re-encode
everything. At 48kbit the sound quality was so good that we took the
opportunity to reencode all 4+ million files to a lower bitrate, hence
reducing file sizes, load time, and costs on bandwidth and storage. It
was a tough choice but we just couldn't hear a difference in sound
quality and doubt that many people will hear any differences either.

Now, on getting playback working again on your platforms. It's going
to be tough for us to switch encoders but maybe it's just a matter of
fine-tuning settings. Tomorrow, I'm going to set up an "AAC decoding
test mix" with differently encoded files so you can tell me which ones
work.

Let's get it all working soon,

Remi

--
Rémi Gabillet
CTO & co-founder, 8tracks
http:8tracks.com/remi

[Gabe Testa]

Remi,

If you send me some samples of the newly encoded files, I can test them very quickly.  

-- Gabe out

---

[Remi Gabillet]

Garth, it's a great idea, I'm hopeful that this is the bug...

I'll follow up with you guys in a couple hours.

[Joel B]

Ok, that will be helpful. I'll also talk to roku to see if they have any clues as to why the files aren't playing.

-Joel

Sent from my iPhone

[Remi Gabillet]

We just found a bug in the library we use to send files to S3
(right_aws) and content types aren't being set properly.

I just manually fixed all 9 tracks on this mix, can you please try playing them:

http://8tracks.com/remi/happy-2nd-birthday-8tracks

[Gabe Testa]

Remi,

Is it possible if you send me a direct link to one of the tracks?  My phone doesn't support 8tracks in the browser but it will play a link to the song.

[Remi Gabillet]

One of the files you can test:

http://8tracks.s3.amazonaws.com/tf/000/474/069/20959.48k.v2.m4a

[Gabe Testa]

That seems to be working on my current device, but i won't be able to test on my programming device until 5:00pm PST today.

I'll let you know as soon as I can.  So far, so good.

Thanks.

[Remi Gabillet]

Sweet! I'll wait to hear back.

Joel, can you tell me if the mix works on Roku?

[ae]

Hi Remi,

Just tested, unfortunately, it still throws the same error. Can you
put that range of test files you mentioned earlier up on AWS and email
the links, and include a few of the older file types for a baseline?

Thanks

- Joel

[Remi Gabillet]

Joel,

Here are a bunch of files you can play with, let me know which ones
work or don't work, thanks!

http://8tr.tmp.s3.amazonaws.com/testfiles/you.64k.old.m4a
http://8tr.tmp.s3.amazonaws.com/testfiles/you.56k.m4a
http://8tr.tmp.s3.amazonaws.com/testfiles/file.2.4.64k.m4a
http://8tr.tmp.s3.amazonaws.com/testfiles/file.5.4.64k.m4a
http://8tr.tmp.s3.amazonaws.com/testfiles/file.5.1.64k.m4a
http://8tr.tmp.s3.amazonaws.com/testfiles/file.5.2.64k.m4a
http://8tr.tmp.s3.amazonaws.com/testfiles/file.129.4.48k.m4a
http://8tr.tmp.s3.amazonaws.com/testfiles/file.2.4.48k.m4a
http://8tr.tmp.s3.amazonaws.com/testfiles/file.29.4.48k.m4a
http://8tr.tmp.s3.amazonaws.com/testfiles/file.5.4.48k.m4a
http://8tr.tmp.s3.amazonaws.com/testfiles/file.132.4.48k.m4a

[Gabriel Testa]

Remi,

So the one that you sent me originally doesn't work on my programming hardware (http://8tracks.s3.amazonaws.com/tf/000/474/069/20959.48k.v2.m4a), but the following ones do:

http://8tr.tmp.s3.amazonaws.com/testfiles/you.64k.old.m4a

http://8tr.tmp.s3.amazonaws.com/testfiles/file.2.4.64k.m4a

http://8tr.tmp.s3.amazonaws.com/testfiles/file.5.2.64k.m4a

http://8tr.tmp.s3.amazonaws.com/testfiles/file.129.4.48k.m4a

http://8tr.tmp.s3.amazonaws.com/testfiles/file.2.4.48k.m4a

http://8tr.tmp.s3.amazonaws.com/testfiles/file.132.4.48k.m4a

The rest didn't work, my device threw a decoding error.

Thanks

Regards,

Gabe Testa

[Remi Gabillet]

Got it, let me review those results...

FYI the numbers in file names are, in order, aot, tms and bitrate:

-aot <int> Audio object type (AOT):
------------------------
2: MPEG-4 AOT 2 (MPEG-4 AAC LC).
5: MPEG-4 AOT 5 (MPEG-4 AAC SBR, i.e. AAC LC + SBR).
29: MPEG-4 AOT 5 (MPEG-4 PS, i.e. AAC LC + SBR + PS).
129: MPEG-2 AAC, LC Profile (corresponds to
MPEG-4 AOT 2, but no support for the PNS
tool).
132: MPEG-2 AAC, LC Profile + SBR (corresponds to
MPEG-4 AOT 5, but no support for the PNS
tool).

-tms <int> Sets the transport format.
Transmux (bitstream) type:
--------------------------
0: Raw (plain access units; not recommended).
1: ADIF (MPEG-2).
2: ADTS (MPEG-2).
3: 3GPP file format.
4: MPEG-4 file format (default).

[Remi Gabillet]

Gabe, it seems that decoding mpeg4 works for LC and PS but not SBR
which is weird. We can get SBR working but we need to use the ADTS
container instead of mpeg4, it doesn't really make sense.

Until we come up with a solution, you may want to use the old files by
substituting 48k.v2.m4a by 64k.m4a.

Alternatively, if you give me the user-agent string for your app, I
can return old file paths directly.

Remi

[Gabe Testa]

How do I find the user agent string for my app?  I never explicitly set one if I remember correctly.

-- gabe out

---

[ae]

Hi Remi, so far, no-go with any except the first file, the old 64kbit
file. I'll forward the testing file links, and the little testing
program I wrote, to Roku to see if they can figure out why, and
perhaps put a fix in the next firmware release (I won't count on it
though)

if you can filter on user-agent string, can your filter on a partial?
the roku User-Agent includes the firmware version info, and the build
info and a few other things.

The first part is always the same though, "Roku/DVP-":

User-Agent: Roku/DVP-3.0 (013.00E02219A)
User-Agent: Roku/DVP-4.1 (024.01E01250A)

other versions known to be in the wild are 2.9 (90% of the Roku
devices out there) and 4.2 (90% of the Roku2 devices).

FYI Gabe, if you can have your software retrieve a file, any file,
from your own website, then check the log files for the User-agent
string.

- Joel

[Gabriel Testa]

Remi,

Here is the user-agent string for a palm pre 2:

Mozilla/5.0 (webOS/2.1.0; U; en-US) AppleWebKit/532.2 (KHTML, like Gecko) Version/1.0 Safari/532.2 Pre/1.2

I'm not exactly sure what the string is for the palm pre, but if you can just check for webOS in the string, I think that would be best.

I appreciate all your work on this.

Thanks ae for helping me find the user-agent.

-gabe out

Regards,

Gabe Testa

[Remi Gabillet]

Joel, it really sucks if Roku can't play any of these files, can you
let me know what Roku says about it?

Since we don't have a clear solution yet, I put in place the
user-agent logic that will serve old aac files for strings matching:
"Roku", "webOS" or "Pre/"

Let me know how that works...

Remi

[ae]

Ok, it's working again! I'm going to test a few mixes and see if this
is true for old and new stuff, so far so good.

- Joel

[Gabe Testa]

My app is working again too.

Thanks remi!

-- gabe out

---

[Remi Gabillet]

Glad we have a fix for now and sorry again for breaking your apps.

I'm not sure how long we can maintain the old files so let's try to
find a solution that would work with the new encoder. Joel, can you
still contact Roku and let me know what they say about the newer
files?

[ae]

Yes, I sent them an email with the file list and a short program that
attempts to play each one sequentially and reports error messages to
the console, so if you can leave those test files up on your site for
a couple of weeks, that would be good, that is typically the turn
around time on getting answers back from them, especially these days
since the Roku2 launched a few weeks ago.

- Joel

[Remi Gabillet]

Awesome Joel, I totally appreciate it!

[Paul Tidwell]

I wish I had a t-shirt to give Remi for being so helpful.


Sent from my Windows Phone

---

From: Remi Gabillet
Sent: 9/21/2011 6:24 PM
To: 8tracks-p...@googlegroups.com
Subject: Re: Playback issues with xxxx.48k.v2.m4a formats

[Remi Gabillet]

lol, thanks Paul, you guys are awesome. The least I can do is help out.