search for: waveformatex

Hi (again), I started to work on an ACM (Audio Compression Manager) for FLAC. I currently only have the canvas. The encoding/decoding is not done yet. So it's completely useless. But since the canvas is the harder thing to start, here it is. (just in case I don't have time to continue) http://mukoli.free.fr/flac-ACM.v0.1.0.zip

Hi Ingo, >It is just a WAVEFORMATEX with a GUID in it. For the ACM system it is just a format with the id >WAVE_FORMAT_EXTENSIBLE and since ACM drivers are not registered by wFormatTag it should be working. >For testing purposes I've written a Vorbis ACM driver, that uses a WAVEFORMATEXTENSIBLE and I experienced >a probl...

On Dec 14, 2014, at 10:02 AM, lvqcl <lvqcl.mail at gmail.com> wrote: > Currently the header of a decoded WAV file can be different to the > original WAV file because FLAC doesn't preserve 'fmt ' chunk. > > For example: create a 24-bit stereo .wav file with WAVEFORMATEXTENSIBLE > header with channel mask == 3. Encode it to .flac then decode back to .wav. > FLAC creates a 24-bit stereo .wav file with WAVEFORMATEX header. Did you try this when using the FLAC command-line option --keep-foreign-metadata? I did not write the code for that option, but I did writ...

...e is the source for this? Do I have to create a separate project that takes these out. I don't get why it isn't included, or where it can be found or what was done. (As well, is there a decent sample of hooking DirectSound to the Vorbis? For example, how to translate the input values to a WaveFormatEX structure, etc...) (As well, what is the purpose of the Windows SDK project? It seems kind of confusing. There is no documentation on how it was compliled, with what debug, what settings...I don't trust it. Its just kind of sitting out there...with documentation copied from libvorbis proje...

...inal .WAV specification (the corresponding structure is called WAVEFORMAT in the win32 sdk and has 14 bytes, the variant you'll typically see in (PCM) wave files is called PCMWAVEFORMAT and has 16 bytes - the size that you expect the format chunk to be). But there's also a newer one, called WAVEFORMATEX, which was created to suit the requirements of non-PCM codecs better. The major differences are that the bits per sample value now officially is part of the wave format structure and that extra header information is supported, if a codec needs it. The size of this extra information is the additiona...

Hi, As a potential user of the Speex ACMs and DirectShow filters to come I am also curious about how many ACM codecs for Speex there are under development right now. Also, the WAVEFORMATEX structure must be planned so that it is extensible, with backward-compatibility, without having to ring back Microsoft for further WAVE_FORMAT tags. For instance, it is a good idea to put a flexible sub-format code in the structure that allows various layouts. I have some experience with that. Pl...

On Sun, 14 Dec 2014 01:14:16 -0800 Erik de Castro Lopo <mle+la at mega-nerd.com> wrote: > > -------------------------- > > Also, I have a question. > > > > Currently flac complains about 24-bit .wav files if they have > > old WAVEFORMATEX header and not 'proper' WAVEFORMATEXTENSIBLE > > header. However it writes such files itself. > > > > Is it better to fix this so it decodes 24-bit .flac files to .wav > > files with WAVEFORMATEXTENSIBLE header? Or is it better to leave > > things as is (for b...

...it instead of refusing it. * Please, if you have a program that's creating these 18 byte chunks, send * a bug report to whoever makes it */ And it was assuming a 16-byte strucuture(PCMWAVEFORMAT) in a file in later code. But why? I think the 18-byte structure in the comment is probably WAVEFORMATEX.... And here's links where the Platform SDK mentions about these structures: (URLs may be broken into a few lines) PCMWAVEFORMAT: http://msdn.microsoft.com/library/default.asp?url=/library/en-us/multimed/hh /multimed/mmstr_7gtu.asp WAVEFORMATEX: http://msdn.microsoft.com/library/default.asp?u...

The commit http://git.xiph.org/?p=flac.git;a=commitdiff;h=99257e177eac96fa41a107b423080232f59ebe45 also requires some changes in write_iff_headers() function: currently flac don't write WAVEFORMATEXTENSIBLE header if decoder_session->channel_mask is equal to 0, 1 or 3. After the commit 99257e17 flac should do this for channel_mask equal to 0, 4 or 3. The patch fixes this. -------------------------- Also, I have a question. Currently flac complains about 24-bit .wav files if they have o...

...that's the bad news, you need an ID from Microsoft to make sure this ID is only used for FLAC. But since it's a 16 bits value, you can probably put anything randomly (only few are reserved). And I don't think it's illegal to use a number like that. Ingo Ralf Blum wrote: >>WAVEFORMATEX >>yes, that's the way to know what the codec does. >>But no WAVEFORMATEXTENSIBLE. on this one. As it's based on the work I >>did on Lame I discovered how to use this in lame. And so you can put as >>many data as you want in the WAV header, ie metadata. So it could be...

Prior to having your ACM codec, I was manually compressing Speex audio and writing it into one stream of an AVI file. To be able to use your codec for playback, I simply appended your WAVEFORMATEX extra data (the extra fields in SPEEXWAVEFORMAT) to the audio format. In looking at your code trying to determine how to fill in that data, it looked like the fmtnotice was optional. Is this truly the case? My application can also use your codec instead of my original method, and that works fine...

...t tag. Since there is only one functional Speex ACM codec available as far as I know, it should use the official format tag. I will be glad to modify our applications to conform to this de-facto standard. Others who may develop ACM codecs in the future either have the option of conforming to the WAVEFORMATEX and data layouts as defined for this tag or register a different tag which would be qualified by their company name (for example). Keith ________________________________________________ Keith Looney Senior Software Engineer On2 Technologies, Inc. The Duck Corporation <p><p>-----Orig...

..., you need to register the codec with Netmeeting. Microsoft offers an API to accomplish this task. http://msdn.microsoft.com/library/default.asp?url=/library/en-us/netmeet/nm3 codec_1xk3.asp The function is called AddACMFormat in the IInstallAudioCodecs COM interface. It takes a fully initialized WAVEFORMATEX structure as well as an extra AUDCAP_INFO structure as arguments. This WAVEFORMATEX structure can be obtained by querying the ACM codec for its supported modes. If you are familiar with COM programming under Windows, this is a task that will not take very long to do (could be done in a single day)...

...t I say. No Codec option has been set. After normalized, I turn on VBR, the speak become very noisy immediately. Anyone has any idea? Also, DTX is still not working. I have gone through the manual but not much info on this area. The following is my setting from sound card using mm_system sdk. WAVEFORMATEX *wfx = (WAVEFORMATEX *)input; wfx->nSamplesPerSec = 8000; wfx->nChannels = 1; wfx->wFormatTag = WAVE_FORMAT_PCM; wfx->wBitsPerSample = 16; wfx->nBlockAlign = 2; wfx->nAvgBytesPerSec = 16000; Thanks in advance, YueWeng __________________________________ Do you Yahoo!...

At the risk of throwing more fuel on the fire, I found the following document on the Microsoft website. It appears to be the file format counterpart to the API documentation presented by Chris Wolf. I'm not familiar with the WAVE format, so I'll let you guys interpret it (or tell me it is irrelevant): http://www.microsoft.com/HWDEV/audio/multichaud.htm [As an aside: Why does Microsoft

Hi, Is there a defined format tag for Opus that should be used with the WAVEFORMATEX structure? See wFormatTag (http://msdn.microsoft.com/en-us/library/windows/desktop/dd390970.aspx). /John

...have a solution that can allow me to achieve my initial goal of compatibility. I can simple write a DirectShow source filter to read the FLAC file, then the ACM codec can treat the stream. And the AVIs with embedded FLAC audio will be readable in every Windows Platform. >Have you tried to use a WAVEFORMATEXTENSIBLE? This should make registration obsolete. I believe the WAVEFORMATEXTENSIBLE structure is available only for WDM audio drivers. Is it true? The WDM drivers are included with all the necessary functionality only in Windows 98SE or later. I think it's a big problem. What do you think? Re...

Christian, I have successfully integrated your ACM codec in our applications, but I have run into one minor issue. In a code comment you imply that fmtnotice is an optional part of the WAVEFORMATEX extra data. I tried to play a file that had no fmtnotice but Windows did not recognize it as valid and did not play the audio. Your work is very much appreciated here and we are anxiously awaiting your integer version of the codec. Also, I notice that you are considering a Vorbis ACM codec. We...

...frames > together. For example, it makes it impossible to recover from corrupted > streams and seeking becomes complicated. I would suggest doing something > similar to what Ogg does. For CBR this works perfectly. The block size in the WAVE file is defined by the nBlockAlign value in the WAVEFORMATEX header. These blocks are of a constant size and facilitate seeking. By grouping a number of frames together the padding loss becomes minimal (or zero). Example: CBR Quality 4 Stereo yields 309 bits per frame. I group eight frames into a block and get 8*309 bits = 309 bytes for the nBlockAlign valu...

HI Josh, I'm starting now to compile the ACM codec. I don't know how long it will take, since I do it in my free time, but I guess it will not take to long. About Mark Powell's comment, with an ACM codec there will be a lot of Windows GUIs for FLAC. I'm writing this message to talk about the FLAC format. The GUIs for the Audio Codec Manager, including Winamp and Windows Media