VLC Audio Drift and Drop Outs on WMA

[argb444]

Hi,

Testing 086i and 093 20080924 on WMA playback. Lots of audio drop outs. Test with mp3 and all is perfect.

-argb

Here are messages from 093..pretty much same as on 086i

asf warning: unknown asf object (not loaded)
asf warning: unknown asf object (not loaded)
avcodec warning: Physical channel configuration not set : guessing
main warning: buffer is 46682 in advance, triggering downsampling
main warning: audio drift is too big (-139961), clearing out
main warning: timing screwed, stopping resampling
main warning: mixer start isn't output start (-60681)
main warning: audio drift is too big (-139379), clearing out
main warning: audio drift is too big (-138561), clearing out
main warning: audio drift is too big (-139561), clearing out
main warning: audio drift is too big (-153561), clearing out
main warning: buffer is 46198 late, triggering upsampling
main warning: resampling stopped after 2431000 usec (drift: -32031)
main warning: buffer is 68250 late, triggering upsampling
main warning: audio drift is too big (145933), dropping buffer
main warning: resampling stopped after 2061000 usec (drift: -52791)
main warning: buffer is 53731 late, triggering upsampling
main warning: timing screwed, stopping resampling
main warning: buffer is 100069 in advance, triggering downsampling
main warning: resampling stopped after 6694000 usec (drift: 53409)
main warning: buffer is 53468 in advance, triggering downsampling
main warning: resampling stopped after 1451000 usec (drift: 17186)
main warning: buffer is 77167 in advance, triggering downsampling
main warning: resampling stopped after 372000 usec (drift: -16120)
main warning: buffer is 62259 late, triggering upsampling
main warning: resampling stopped after 1131000 usec (drift: 44425)
main warning: buffer is 44484 in advance, triggering downsampling
main warning: timing screwed, stopping resampling
main warning: buffer is 104898 in advance, triggering downsampling
main warning: resampling stopped after 371000 usec (drift: -34804)
main warning: buffer is 80944 late, triggering upsampling
main warning: resampling stopped after 1078000 usec (drift: -24282)
main warning: buffer is 70423 late, triggering upsampling
main warning: resampling stopped after 2443000 usec (drift: 97929)
main warning: buffer is 97747 in advance, triggering downsampling
main warning: resampling stopped after 371000 usec (drift: -41956)
main warning: buffer is 42138 late, triggering upsampling
main warning: resampling stopped after 560000 usec (drift: -42190)
main warning: buffer is 61430 in advance, triggering downsampling
main warning: resampling stopped after 557000 usec (drift: 14824)
main warning: buffer is 75285 in advance, triggering downsampling
main warning: resampling stopped after 556000 usec (drift: 75119)
main warning: buffer is 74937 in advance, triggering downsampling
main warning: audio drift is too big (-122017), clearing out
main warning: timing screwed, stopping resampling
main warning: mixer start isn't output start (-45511)
main warning: output date isn't PTS date, requesting resampling (-46000)
main warning: buffer is 47581 late, triggering upsampling
main warning: resampling stopped after 386000 usec (drift: -32896)
main warning: buffer is 80277 late, triggering upsampling
main warning: audio drift is too big (126295), dropping buffer
main warning: resampling stopped after 558000 usec (drift: -32889)
main warning: buffer is 119970 in advance, triggering downsampling
main warning: audio drift is too big (-120128), clearing out
main warning: timing screwed, stopping resampling
main warning: mixer start isn't output start (-56405)
main warning: buffer is 92819 late, triggering upsampling
main warning: audio drift is too big (139552), dropping buffer
main warning: resampling stopped after 1270000 usec (drift: 57053)
main warning: buffer is 82486 late, triggering upsampling
main warning: resampling stopped after 1131000 usec (drift: 24198)
main warning: buffer is 68141 late, triggering upsampling
main warning: resampling stopped after 760000 usec (drift: -7469)
main warning: buffer is 54849 late, triggering upsampling
main warning: resampling stopped after 1503000 usec (drift: 6012)
main warning: buffer is 63153 in advance, triggering downsampling
main warning: resampling stopped after 744000 usec (drift: -29720)
main warning: buffer is 76100 late, triggering upsampling
main warning: resampling stopped after 571000 usec (drift: 77144)
main warning: buffer is 76962 in advance, triggering downsampling
main warning: resampling stopped after 371000 usec (drift: -16301)
main warning: buffer is 62441 late, triggering upsampling
main warning: resampling stopped after 1131000 usec (drift: -2197)
main warning: buffer is 44303 in advance, triggering downsampling
main warning: resampling stopped after 1081000 usec (drift: 8677)
main warning: buffer is 84663 late, triggering upsampling
main warning: resampling stopped after 374000 usec (drift: -38539)
main warning: buffer is 68641 in advance, triggering downsampling
main warning: resampling stopped after 372000 usec (drift: -24646)
main warning: buffer is 82496 in advance, triggering downsampling
main warning: resampling stopped after 557000 usec (drift: -10549)
main warning: buffer is 96351 in advance, triggering downsampling
main warning: resampling stopped after 373000 usec (drift: 3064)
main warning: buffer is 43316 late, triggering upsampling
main warning: resampling stopped after 1453000 usec (drift: 13962)
main warning: buffer is 74423 in advance, triggering downsampling
main warning: resampling stopped after 557000 usec (drift: 27818)
main warning: buffer is 88278 in advance, triggering downsampling
main warning: resampling stopped after 373000 usec (drift: 41432)
main warning: buffer is 52133 in advance, triggering downsampling
main warning: resampling stopped after 372000 usec (drift: -41153)
main warning: buffer is 41335 late, triggering upsampling
main warning: timing screwed, stopping resampling
main warning: buffer is 87534 late, triggering upsampling
main warning: audio drift is too big (133552), dropping buffer
main warning: resampling stopped after 379000 usec (drift: 6030)
main warning: buffer is 41350 late, triggering upsampling
main warning: audio drift is too big (-159072), clearing out
main warning: timing screwed, stopping resampling
main warning: mixer start isn't output start (-73072)
main warning: audio drift is too big (139260), dropping buffer
main warning: buffer is 46381 late, triggering upsampling
main warning: timing screwed, stopping resampling
main warning: buffer is 93318 late, triggering upsampling
main warning: resampling stopped after 1320000 usec (drift: 60093)
main warning: audio drift is too big (-120794), clearing out
main warning: mixer start isn't output start (-52920)
main warning: buffer is 92638 late, triggering upsampling
main warning: audio drift is too big (139085), dropping buffer
main warning: resampling stopped after 1270000 usec (drift: 57212)
asf warning: unknown asf object 0x44231c94-0x9498-0x49d1-0xa1411d134e457054
asf warning: unknown asf object 0x1806d474-0xcadf-0x4509-0xa4ba9aabcb96aae8

[Jean-Baptiste Kempf]

Try with DMO, if you can.

[amri123]

i have enable DMO in configure as --enable dmo ,,bt it still isnt playing WMA files..

[VLC_help]

Can you give sample file?

[argb444]

Yes. Where do I upload the file?

-argb

[amri123]

is it possible to upgrade the ffmpeg ,,so that it can support WMA playback.Actually i am having the same problem with it.Almost everything is playing except WMA.I have also done --enable-dmo with no result.Though i can play WMA from command line with --codec dmo option.But is there any way to play without command line.Pls help.By the way i am building VLC 0.8.6d version.

[VLC_help]

argb444:
ftp://ftp.videolan.org/incoming/
and report back the filenames (please upload file and same named text file that explains the issue)

or use rapidshare or megaupload if you don't use ftp.

[argb444]

Uploaded Breezin.zip to ftp.videolan.org/incoming

-argb

[argb444]

Hi,

Quick ping to see if you were able to test with the file I uploaded.

-argb

[VLC_help]

I don't have access to that FTP

[argb444]

I just resent the file.

-argb

[VLC_help]

File is there (but stuff isn't shown to public nor is it downloadable).

[argb444]

File is there (but stuff isn't shown to public nor is it downloadable).

Sorry, but I am confused. Did you get the zip file that I uploaded?

If you did not get the file, please tell me how to send it to you.

-argb

[VLC_help]

I am not official dev, so I don't have access to FTP. You can use Rapidshare or Megaupload or some similar service for uploading.

[VLC_help]

I can confirm this happens with sample file you sent. Can I share the file link to public? (so I can open trac ticket with sample file)

[argb444]

Here is a public link to the test file.

http://www.megaupload.com/?d=HJJMLIZU

-argb

[VLC_help]

http://trac.videolan.org/vlc/ticket/1817
I added the sample to existing trac ticket. Thanks.

[mpbb]

I have the same problem with WMA audio files. No issues with other players or mp3 files. Something related to vc-1 codec ?. Tried the last nightly build and it did not solve the issue. I'm currently reverting to 0.8.6i (never noticed this problem, so I guess it will work anew).

Seems to me a pretty serious bug (unless it concerns only specific wma files). Actually I'm surprised there has been little feedback/complaint and even more that this seems to be dragging for 4 months and it's not even in the queue for 1.0.0.

[mpbb]

The funny thing is the choppiness now remains in the compiled 0.8.6. Guess it wasn't there before as I'm pretty sure I would have noticed that, so would it be an Ibex issue, with any codec upgrade ?

Still, only VLC seems to "uncover" this issue. In my wma files the effect is much worse than this megaupload sample.

[mpbb]

Ok I've just noticed these posts were in the windows thread, so it seems this bug is cross-platform... Should I open a similar one in the linux thread ?

[VLC_help]

You can open new thread, but I don't think it will change anything. I think the issue lies in audio decoder (another libavcodec problem).

[mpbb]

You can open new thread, but I don't think it will change anything. I think the issue lies in audio decoder (another libavcodec problem).

Why then I´ve been able to reproduce the issue on my WinXP on the same dual-booted machine ?

Does VLC port libavcodec to Windows ? And wouldn´t direct windows codec solve the issue ( have tried "direct rendering" option but not sure this is the right option for using the native codecs if any)

[argb444]

Hi,

I ran some additional tests today. Here is a link to a zip containing the test WMA files, Metadataedit.exe tool, and detailed results. http://www.megaupload.com/?d=FMF0C06K

Test: Same source .WAV file encoded to WMA 128 Kbps using two different encoder tools.

Result: There is a difference in Bitrate between the two files as reported by metadataedit.exe.
ODP-WMA128.wma - 129297 - This file produces the audio problems when streamed by VLC
WME-WMA128.wma - 128639 - This file plays ok when streamed by VLC

File 1 - ODP-WMA128.wma
Encoder: Windows On-Demand Producer (WMODP), an old tool
Playback: Audio drop outs and skips when streamed by VLC using codec=mpga

File 2 - WME-WMA128.wma
Encoder: Windows Media 9 Encoder version 9.00.00.3352
Playback: No audio playback problems when streamed with VLC using codec=mpga

ODP-WMA128.wma - Metadataedit partial output
* Idx Name Stream Language Type Value
* --- ---- ------ -------- ---- -----
* 0 Duration 0 0 QWORD 2524360000, 0x000000009676ad40
* 1 Bitrate 0 0 DWORD 129297, 0x0001f911

WME-WMA128.wma - Metadataedit partial output
* Idx Name Stream Language Type Value
* --- ---- ------ -------- ---- -----
* 0 Duration 0 0 QWORD 2523080000, 0x0000000096632540
* 1 Bitrate 0 0 DWORD 128639, 0x0001f67f

-argb

[mpbb]

That's very interesting, arg.

So it seems indeed about encoding quality. I deeply suspect the wma files I played are very poorly encoded by some cheap freeware, hence the issue is so noticeable for me.

It also explains why this issue got relatively little attention.

But i would say it also confirms its seriousness, as many people might be having only slight drifts and not noticing it even with relatively good encodings but affecting the overall fidelity.

Wouldn't this qualify to raise even further this bug to major or its severity to critical ?

[argb444]

Your encodings are probably ok, rather I think VLC is having trouble decoding older WMA v2 files.

The WMA file in the test package that VLC is having trouble with is older WMA v2, but it plays perfectly for me in Windows Media Player, and Media 9 Streaming Services has no trouble streaming it.

I have couple thousand WMA V2 files that were created with the old On-Demand Producer (ODP) encoder tool going as far back as 1999 and they all play back just fine in WMP today.

Maybe these test files will help VLC team isolate the problem For anyone else to try also -
http://www.megaupload.com/?d=FMF0C06K

-argb