Talk:WAV

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Type 350[edit]

Does anyone know what this codec type is, or where I could find out? Mr. Jones 10:07, 1 Jul 2004 (UTC)

Lossy/lossless[edit]

I'm confused, this article describes PCM as lossless whereas all other articles seem to describe it as lossy (Lossy data compression, List of codecs). --gb 08:31, Feb 16, 2005 (UTC)

Don't mix up PCM and ADPCM. The first is "lossless", but the latter can be lossy.
According to the article, PCM is also uncompressed (which is why it it lossless -_-). This would seem to indicate that ADPCM is compressed.
You could also store data lossy without using compression, e. g. if you have a format with floating point values instead of integers :o) — 91.4.31.52 20:13, 5 November 2006 (UTC)[reply]
Why would one want to "store data lossy without using compression" ? The loss that the article is about is loss whose consequence in the data (image, sound or whatever) is never desireable but may be considered tolerable as the price for the benefit of compacting the data. Floating point values just have smaller (finite and non-constant) quantising steps than integer values. (cuddlyable3) 84.210.139.189 19:53, 18 November 2006 (UTC)[reply]
32bit Floating point can easily cover all 16bit integer numbers without any quantization effects. Quite the contrary: 32 bit floating is able to cover integers up to 25 bit (signed). The definition of lossless can be stated as follows: If a certain number format is capable to represent the input format without quantization or similar the encoding process is lossless (i.e. if the input signal can be completely reconstructed from the encoded signal). This does not depend only on the number format but also on the input signal. This implies that for each input signal which has to be encoded an appropriate encoding must be found which can fully (non-destructively) cover the input number range. E.g. if the input signal has a dynamic of 8 bits, the signal can be encoded lossless using 8 bits PCM. Compression has nothing to do with it. Compression is per definition a lossless process. If something can be lossy than it is encoding. Take mp3 for instance: The encoding is based on psycho-acoustical models what can result in a data reduction which can be (to trade space for exactness) lossy. Once encoded, the output stream gets compressed by a runlength compression. This runlength compression is completely reversible and that's the reason why it's a compression. Please respect the simple statutes for editors of encyclopaedias: First get the knowledge, then write. Wikipedia does not profit when it spreads misinformation only because of some writing exercises of some self-exposers.Cls.nebadje 11:07, 8 February 2007 (UTC)[reply]
Actually, PCM is not really lossless. PCM is a way to store sound, which by definition is an analogue signal, in a digital way. Analogue signals have an infinite amount of possible sample values, whereas PCM represents samples with a finite number of values. Any "real" sample value that is in between PCM's possible values is rounded to the nearest representable sample value. So, PCM is lossless only in the sense that no data is lost apart from the loss caused by digitalization.Cassandra B 17:49, 22 April 2007 (UTC)[reply]
I have removed the statement suggesting LPCM is "lossless". The term usually refers to data compression, and the word was even linked to the lossless data compression article. However, LPCM in WAV is not compressed therefore cannot be lossless nor lossy in this sense. There is no loss of data involved, but it is improper use of such terminology. Note how BMP file format does not suggest it is "lossless", as similarly it is an uncompressed format. --Zilog Jones (talk) 17:37, 20 May 2009 (UTC)[reply]

Amount of channels[edit]

How many audio channels can a wav file have? --Zilog Jones 00:01, 10 February 2007 (UTC)[reply]

Technically 65535 channels, because WAVEFORMATEX::nChannels is 16 bits. Motonari 17:52, 29 September 2007 (UTC)[reply]

The Codec Comparison Table[edit]

The values in "1 min" column are wrong. For example "11,025 Hz 16 bit PCM" is said to be "1291k" per minute. Thats just the Prefix it doesn't have any unit of measurement. I guessing it should be Byte? And shouldn't the value be ((Bitrate * 60)/8)? —Preceding unsigned comment added by 88.112.71.53 (talk) 02:19, 25 September 2007 (UTC)[reply]

Limit[edit]

I'm don't think the limit calculation is accurate. If the maximum file size is 2^32 bytes, then by my calculation the file can be up to 13.5 hours.[1]. The issue may be that some programs treat the file size as an signed integer, which would limit it to 2^31 bytes. However, I think the format itself uses unsigned. Superm401 - Talk 10:46, 9 November 2007 (UTC)[reply]

The limit calculation is correct, because it assumes stereo.Motonari 02:55, 11 November 2007 (UTC)[reply]
Implementations often take -1 (0xFFFFFFFF) in the size field as "length unknown" and therefore will play until the file ends. If you only have one chunk, that does the right thing. Otherwise, one uses superchunks to overcome this limitation — movies packaged into a RIFF/AVI are commonly superchunked at 1 GB boundaries. Not sure how exactly the binary layout is, but I suppose it is just a concatenation of multiple RIFFs. ("RIFF" <length> <payload> "RIFF" <length> <payload>...) -j.engelh (talk) 23:32, 5 March 2008 (UTC)[reply]

Why is there no example file?[edit]

I want an example wav file on this site. Yes sir. —Preceding unsigned comment added by 83.254.4.90 (talk) 21:48, 12 March 2008 (UTC)[reply]

Example provided, Sir. Bestfaith (talk) 19:53, 28 October 2015 (UTC)[reply]
I reverted. The hex file dump is too detailed for an encyclopedia. Glrx (talk) 21:10, 30 October 2015 (UTC)[reply]
Please discuss. User Girx deleted a short example wav file with a summary "We don't need a hex dump in an encyclopedia; this is not a tutorial about generating wave files". Is there a good argument why articles about file formats such as .bmp and .gif offer examples but the .wav article may not? Blooteuth (talk) 03:20, 12 November 2017 (UTC)[reply]

Signed vs Unsigned - what is "standard"?[edit]

A "standard" .wav file is signed, 16-bit, little-endian. The easy way to tell is to generate a short section of silence, and note that the data values are all 0000. —Preceding unsigned comment added by 87.194.171.29 (talk) 20:36, 31 July 2008 (UTC)[reply]

8-bit WAV files are unsigned, everything above that is signed. That's the "standard" to my knowledge. Radiodef (talk) 22:55, 10 August 2013 (UTC)[reply]

Compression section needs intro[edit]

The section WAV file compression codecs compared simply starts with no discussion of how compression in WAV files is accommodated, or how it is rare. I see a need for an introductory paragraph. (I can't write this as I know nothing about compressed WAV. I was unaware such a thing even existed.) Also, I am not sure that the long table is appropriate. The article is about WAV; it is not about comparing different audio compression algorithms. What do others think? HairyWombat (talk) 20:30, 23 September 2009 (UTC)[reply]

The format chunk lets you specify the format of the audio data. WAV files are almost always 1 for uncompressed PCM and then the audio is raw samples in a big line but you can put whatever you want in the header. I will keep this in mind and try to find a reference for the codes. Radiodef (talk) 23:02, 10 August 2013 (UTC)[reply]

Non-audio data[edit]

It seems the sampling rate can be set anywhere from 1 Hz to 4.3 GHz, and it has no problem storing signals down to DC. Has anyone used WAV files to store non-audio data, like low-frequency seismic recordings or high-frequency ultrasound?

Apparently so.

LTspice can write .wav audio files. These files can then

be listened to or be used as the input of another simulation. ... <Nbits> is the number of sampling bits. The valid range is from 1 to 32 bits. <SampleRate> is the number of samples to write per simulated second. The valid range is 1 to 4294967295 samples be second. The remainder of the syntax lists the nodes that you wish to save. Each node will be an independent channel in the .wav file. The number of channels may be as few as one or as many as 65535. It is possible to write a device current, e.g., Ib(Q1) as well as node voltage. The .wav analog to digital converter has a

full scale range of -1 to +1 Volt or Amp.

http://ltspice.linear.com/software/scad3.pdf —Preceding unsigned comment added by 71.167.63.131 (talk) 14:59, 30 September 2009 (UTC)[reply]

Article title -- abbreviation?[edit]

I wonder whether the article title should in fact be Wave Audio File Format, with WAV redirecting to this location? Given that it is the full name of the format s. AIFF (Audio Interchange File Format) currently works this way and I think it works better. Any thoughts? Fattonyni (talk) 14:58, 28 December 2009 (UTC)[reply]

Yes, I think it should be WAVE. WAV name is just MSDOS victim. —Preceding unsigned comment added by Ijauhsdfjsik (talkcontribs) 01:12, 22 March 2010 (UTC)[reply]
Done. Done. Changed to the full format name Waveform Audio File Format, just the same as Audio Interchange File Format is for AIFF, so better logically. Jimthing (talk) 05:19, 26 January 2011 (UTC)[reply]
Undone. In the future, please make a request for move instead. --Hinata talk 18:35, 26 January 2011 (UTC)[reply]

.WV is not the same as WAV[edit]

.wv is file extension of wavpack —Preceding unsigned comment added by 62.168.56.1 (talk) 13:12, 10 February 2010 (UTC)[reply]

POPULARITY Section[edit]

I have some doubts about this section. A discussion of lossy formats and why they're commonly used may be interesting in itself, but perhaps this article is not the best place to discuss this. Also, given that things change over time, the very idea of a section called "POPULARITY" is liable to become unstuck over time. 92.234.48.114 (talk) 14:52, 17 November 2010 (UTC)[reply]

Requested move[edit]

The following discussion is an archived discussion of the proposal. Please do not modify it. Subsequent comments should be made in a new section on the talk page. No further edits should be made to this section.

No consensus to move. Vegaswikian (talk) 06:10, 2 February 2011 (UTC)[reply]

WAVWaveform Audio File Format — Shall this article be moved from WAV to Waveform Audio File Format, in the manner of the AIFF article title Audio Interchange File Format? Binksternet (talk) 18:48, 26 January 2011 (UTC)[reply]

  • Oppose. Overall the result would be less consistency, not more. WP:LOWERCASE reads in part Abbreviations and acronyms are generally avoided unless the subject is almost exclusively known by its abbreviation (e.g. NATO and Laser) (my emphasis). This rule is fairly consistently applied in Wikipedia and should be followed where it applies. Does it apply? Most certainly: Many, perhaps most, who regularly use the term WAV would not know (or care) exactly what it stands for. Andrewa (talk) 21:34, 26 January 2011 (UTC)[reply]
  • Oppose WP:COMMONNAME. No one calls it "waveform audio file format", does anyone even know it is an abbreviation for anything other than "wave"? 184.144.161.95 (talk) 23:09, 26 January 2011 (UTC)[reply]
  • Oppose Andrewa is right. It is almost exclusevly known as WAV, so WP:COMMONNAME should apply. --Hinata talk 23:11, 26 January 2011 (UTC)[reply]
  • Oppose - I agree with the above sentiments.  — Amakuru (talk) 15:55, 28 January 2011 (UTC)[reply]
  • Oppose - agree with the above. --mcld (talk) 15:02, 31 January 2011 (UTC)[reply]
The above discussion is preserved as an archive of the proposal. Please do not modify it. Subsequent comments should be made in a new section on this talk page. No further edits should be made to this section.

No information fields?[edit]

I'm not a specialist, so I might be wrong about something; but, for example, if you use FL Studio to generate a WAV file, and if you have Artist / Title information stored inside the project, the resulting WAV file seems to have this information inside it. For example, Winamp shows this information, but you can't edit it (File info option just shows info about number of channels, etc.) Foobar and some other players, on the other hand, don't show this info. If necessary, I can provide a WAV file containing this Artist / Title information as an example (not violating the copyright - it's my own mashup). —Preceding unsigned comment added by 93.100.51.220 (talk) 23:51, 11 January 2011 (UTC)[reply]

There is a RIFF INFO chunk that can hold information about title, artist, and copyright. Some players will ignore the INFO chunk, so they won't display its information. Some editors may show the information but not let you edit it. Perversely, some programs may know about the INFO chunk, but they may not find it in the WAV file. Nothing about what you've described above is unusual. It would be nice if all programs processed the INFO chunk, but that is not the case.
The documentation about RIFF files strongly suggests that one can add an INFO chunk to a WAV file, but the syntactic specification of the WAV file doesn't show where the chunk should go. There's a general notion that programs that read RIFF files (and therefore WAV files) should ignore chunks they don't recognize, so including an INFO chunk in a WAV file should not hurt -- a conforming reader should just ignore it. However, many programs don't follow the rules and get confused by unknown chunks. On the other hand, programs that know about INFO chunks may expect the chunk in a particular position. Some WAV writers put the INFO chunk first to make it handy, but I've had programs crash if the INFO chunk precedes the format chunk. Some vendors put the INFO chunk at the end so brittle readers have a better chance of coping; the result, however, is readers looking for an INFO chunk up front may miss it. Conceivably, some programs may find and process an INFO chunk, but then not find the wave format and samples. Sadly, adding an INFO chunk can be a form of Russian roulette.
Glrx (talk) 21:04, 1 March 2011 (UTC)[reply]

The "Use by broadcasters" part is completely uninteresting. — Preceding unsigned comment added by 82.236.187.110 (talk) 14:07, 16 July 2011 (UTC)[reply]

Standard[edit]

Waveform Audio File Format [...] is a Microsoft and IBM audio file format standard [...] If it's a standard, under what has it been standardized (ISO/IEC,...)??? — Preceding unsigned comment added by 195.148.98.77 (talk) 14:44, 6 September 2012 (UTC)[reply]

A company (or an alliance) can create a standard without ISO/IEC/ANSI. It happens all the time. Glrx (talk) 15:45, 7 September 2012 (UTC)[reply]

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