[SOLVED!] Converting Variable Sample Rate to Constant Sample Rate

[Midzuki]

Does anybody know a 100%~software-based way to convert correctly
VSR .wma files into CSR uncompressed audio? Lately I've been forced to record
from the analog output of the sound card and re-digitize the analog recording
in order to avoid loss of audio-video sync.

[Midzuki]

Too bad the "pros" keep assuming that variable~sample-rate .WMAs
"do not/cannot exist", so that they can keep ignoring the ASF audio-timecoding
when they design their file-format converters.

[Soopafresh]

This app will convert them to WAV. Dunno if that helps.

http://www.aoamedia.com/audioextractor.htm

[Midzuki]

Thanks for the attention, Soopafresh,
but I serious doubt that "AoA AudioExtractor" can do
much more than simply extract a "raw" PCM byte-stream from
a WMA file and happily assume it must be played at a constant sample rate
from the beginning to the end.

[cd090580]

Why not trying to use GraphEdit and build a graph that decompress the wma and save it to wav.

This way, it will use the same decoder as WMP uses.

[Midzuki]

cd090580 wrote:

Why not trying to use GraphEdit and build a graph that decompress the wma and save it to wav.

Already tried that. The result is a .WAV file whose playing time is
several seconds shorter than the original .WMA track.

[Midzuki]

I have just tried Mplayer:

mplayer -vo directx -ao pcm:file=filename.wav filename.ASF

As already expected ,
another application unable to do the job.

HOWEVER, at least it did something funny.
Keep reading, please.

[C:\]
=>cd mplayer

[C:\MPlayer]
=>mplayer -vo directx CENSORED.wmv

MPlayer dev-SVN-r25953-4.2.3 (C) 2000-2008 MPlayer Team
CPU: Intel(R) Pentium(R) 4 CPU 1500MHz (Family: 15, Model: 0, Stepping: 10)
CPUflags: MMX: 1 MMX2: 1 3DNow: 0 3DNow2: 0 SSE: 1 SSE2: 1
Compiled with runtime CPU detection.
117 audio & 239 video codecs

Playing CENSORED.wmv.
ASF file format detected.
[asfheader] Audio stream found, -aid 1
[asfheader] Video stream found, -vid 2
VIDEO: [WMV3] 854x480 24bpp 1000.000 fps 851.0 kbps (103.9 kbyte/s)
Clip info:

<SNIP>

================================================== ========================

Opening video decoder: [dmo] DMO video codecs
IMediaObject ERROR: 00E06320 could not open DMO DLL (0x0 : 0)
Failed to create DMO filter
ERROR: Could not open required DirectShow codec wmv9dmod.dll.
You need to upgrade/install the binary codecs package.
Go to http://www.mplayerhq.hu/dload.html
VDecoder init failed
Opening video decoder: [dmo] DMO video codecs
IMediaObject ERROR: 00E064D6 no such class object (0x80004001 : -2147467263)
Failed to create DMO filter
ERROR: Could not open required DirectShow codec wmvdmod.dll.
You need to upgrade/install the binary codecs package.
Go to http://www.mplayerhq.hu/dload.html
VDecoder init failed
Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family
Selected video codec: [ffwmv3] vfm: ffmpeg (FFmpeg WMV3/WMV9)
================================================== ========================
================================================== ========================
Opening audio decoder: [ffmpeg] FFmpeg/libavcodec audio decoders
AUDIO: 48000 Hz, 2 ch, s16le, 64.0 kbit/4.17% (ratio: 8001->192000)
Selected audio codec: [ffwmav2] afm: ffmpeg (DivX audio v2 (FFmpeg))
================================================== ========================
AO: [dsound] 48000Hz 2ch s16le (2 bytes per sample)
Starting playback...
VDec: vo config request - 854 x 480 (preferred colorspace: Planar YV12)
VDec: using Planar YV12 as output csp (no 0)
Movie-Aspect is undefined - no prescaling applied.
VO: [directx] 854x480 => 854x480 Planar YV12
New_Face failed. Maybe the font path is wrong.
Please supply the text font file (~/.mplayer/subfont.ttf).
subtitle font: load_sub_face failed.
New_Face failed. Maybe the font path is wrong.
Please supply the text font file (~/.mplayer/subfont.ttf).
subtitle font: load_sub_face failed.
A: 29.5 V: 29.5 A-V: 0.006 ct: -0.043 256/256 2% 36% 0.0% 56 0

************************************************
**** Your system is too SLOW to play this! ****
************************************************

Possible reasons, problems, workarounds:
- Most common: broken/buggy _audio_ driver
- Try -ao sdl or use the OSS emulation of ALSA.
- Experiment with different values for -autosync, 30 is a good start.
- Slow video output
- Try a different -vo driver (-vo help for a list) or try -framedrop!
- Slow CPU
- Don't try to play a big DVD/DivX on a slow CPU! Try some of the lavdopts,
e.g. -vfm ffmpeg -lavdopts lowres=1:fastkiploopfilter=all.
- Broken file
- Try various combinations of -nobps -ni -forceidx -mc 0.
- Slow media (NFS/SMB mounts, DVD, VCD etc)
- Try -cache 8192.
- Are you using -cache to play a non-interleaved AVI file?
- Try -nocache.
Read DOCS/HTML/en/video.html for tuning/speedup tips.
If none of this helps you, read DOCS/HTML/en/bugreports.html.

( etc. etc. etc. )

It seems certain software writers are somewhat out-of-touch with reality.

[Midzuki]

At last... ... ...



1) add the fukking wma to the playlist of WinAmp;

2) goto Icon Menu, Options, Preferences, Plug-ins, Output,
NullSoft Disk Writer; configure, OK, close;

3) Click the Play button;

4) Voilà!

5) Windows Media Audio sucks, Windows Movie Maker sucks,
Windows Media Encoder sucks, Bill Gates is a very sexy man.

[Midzuki]

[ UPDATE ]

I have just found another workaround:
use WMVMuxer for converting the lossy WMA streams into lossless WMA files
— these latter do not have the infamous variable sample-rate thing, and thus
they can be re-encoded to a non-M§ lossy format without synchronization issues.
[s:8e5a396f16]This method is superior to the use of Winamp's Disk Writer plugin because
it's able to produce a CSR multichannel output.[/s:8e5a396f16]

[EDIT]
Now I have to correct myself. Because WMVmuxer can convert lossy stereo WMA to Lossless stereo WMA, I happily assumed it was able to do the same to
*multichannel* audio. Not true, sadly. Yes, WMNicEnc is capable of encoding to
multichannel Windows Media Audio, however there are no guarantees that the outputs
created in this way will always be "100% OK".


For the curious, here goes the .prx file I used upon a
common stereo WMA track sampled @ 48kHz: <-- ( This one works for me )

<profile version="589824"
storageformat="1"
name="WMA-old-To-WMA-lossless"
description="">
<streamconfig majortype="{73647561-0000-0010-8000-00AA00389B71}"
streamnumber="1"
streamname="Audio Stream"
inputname="Audio409"
bitrate="128016"
bufferwindow="-1"
reliabletransport="0"
decodercomplexity=""
rfc1766langid="en-us"
vbrenabled="1"
vbrquality="100"
bitratemax="0"
bufferwindowmax="0">
<wmmediatype subtype="{00000163-0000-0010-8000-00AA00389B71}"
bfixedsizesamples="1"
btemporalcompression="0"
lsamplesize="12288">
<waveformatex wFormatTag="355"
nChannels="2"
nSamplesPerSec="48000"
nAvgBytesPerSec="2147483492"
nBlockAlign="12288"
wBitsPerSample="24"
codecdata="1800030000000000000000000000A1010000"/>
</wmmediatype>
</streamconfig>
</profile>

[Midzuki]

Yet another method --- this time, by using the Avisynth plugins
bassAudio and SoundOut:

LoadPlugin("Path-To\bassAudio.dll")
LoadPlugin("Path-To\SoundOut.dll")
BassAudioSource("audio.wma")
SoundOut()

[jagabo]

Play the source in one program, record "What you hear" in another?

[Midzuki]

Play the source in one program, record "What you hear" in another?

Well, to say "record what we hear" may be somewhat misleading.
IF the recording software emulates an analog audio capture, then it will work,
otherwise it won't --- it's pointless to get the uncompressed bitstream from a
WMA track without honoring the timestamps in the ASF container.
I had already tried both Goldwave and Total Recorder, and they both failed ---
--- not much different from Avisynth's DirectShowSource.

[jagabo]

Play the source in one program, record "What you hear" in another?

Well, to say "record ``what we hear´´" may be somewhat misleading.
IF the recording software emulates an analog audio capture, then it will work

"What you hear" is the final output pin of the system mixer -- just before audio goes to the sound card. Some cards/drivers call this "Stereo Mix" or some other name. I believe it's always at a fixed sample rate (ie, the mixer can take several inputs at several different sample rates from several programs, and convert them all to one fixed rate before sending to the audio card). Just don't do other stuff while recording or all your system sounds (clicks, beeps, boops, new mail, etc) will be recorded too.

Can you point to, or upload, some sample files?

[Midzuki]

https://forum.videohelp.com/topic349802.html#1839687

[jagabo]

I didn't see any samples I could download in that thread.

[Midzuki]

I will PM you, then.
Currently I am on a dial-up connection,
which makes the file transfers above 20MB quite unpractical.

[jagabo]

I can take a torrent link if that will help you.

[Midzuki]

[ e d i t e d ]