Tom White

Vista SP1 and 24 Bit Audio

Tom White — Mon, 04 Aug 2008 21:01:00 GMT

The following suggestions were derived from a discussion thread on the the WDM Audio Developers mailing list. Disclaimer: These suggestions are not from Microsoft, and may not be the preferred solution to the problem being discussed, but are being published here because they did solve the problem in these specific examples.

Q: We've had reports that installing Windows Vista SP1 removes all of the 24-bit formats from the Advanced tab for devices in the Sound control panel. Is there anything that would have changed with SP1 that would cause this?

A1: Check your DataRangeIntersection handler and make sure it's not rejecting PKSDATARANGE_AUDIO requests with MaximumBitsPerSample set to 24. Although the WDK documentation (under "PCM High Bitdepth Stream Data Range") says that MaximumBitsPerSample is set to the container size (in this case 32 bits), Vista doesn't. The RTM build of Vista ignored a STATUS_NO_MATCH return, but SP1 doesn't and therefore disallows all 24-bit formats. Make the DataRangeIntersection handler accept a MaximumBitsPerSample value of 24, and everything should work.

A2: If the pWaveFormatEx->dwChannelMask returned by DataRangeIntersection() is set to KSAUDIO_SPEAKER_DIRECTOUT, no 24-bit formats show up in Windows Vista SP1, as they did in earlier OS releases (including Windows Vista RTM). Setting pWaveFormatEx->dwChannelMask to KSAUDIO_SPEAKER_STEREO makes the 24-bit formats reappear.

Troubleshooting Audio Performance Issues (Part 2)

Tom White — Mon, 04 Aug 2008 20:08:00 GMT

More Audio Performance Tools and Tips

Audio Device Performance and Windows XP: Best Practices for Drivers

http://www.microsoft.com/whdc/archive/highperf-drv.mspx

Windows Performance Tools Kit, v.4.1.1 (QFE)

tools: http://www.microsoft.com/whdc/system/sysperf/perftools.mspx

docs: http://msdn.microsoft.com/en-us/library/cc305187.aspx

Pigs Can Fly: Windows performance, development, and related issues

http://blogs.msdn.com/pigscanfly/default.aspx

Troubleshooting Audio Performance Issues Part 1 (Updated)

Tom White — Tue, 08 Jul 2008 23:38:00 GMT

These links are collected from articles about troubleshooting audio performance issues in Vista:

http://www.thesycon.de/deu/latency_check.shtml

According to posters on the Project BarBQue mailing list, one of the primary performance metrics is the time spent at "DPC level", a driver dispatch level where access to system resources is first come, first served. If a lot of time is spent at DPC level, it affects the entire system. USB and firewire audio devices often have very tight timing margins, where their drivers must respond to interrupts within a very narrow
time interval. If *anything* else is running at DPC level when they need this timeslot, you'll get glitches.

DPC Latency Checker is a Windows tool that analyses the capabilities of a computer system to handle real-time data streams properly. It may help to find the cause for interruptions in real-time audio and video streams, also known as drop-outs.

http://www.microsoft.com/whdc/DevTools/tools/RATT.mspx

RATTV3 is a tool for auditing the execution times of interrupt service routines (ISRs), deferred procedure calls (DPCs), and timer DPCs on systems that are running Windows XP. RATTV3 is designed to help developers of drivers and other kernel mode components audit the ISR and DPC execution time of their components.

http://technet.microsoft.com/en-us/sysinternals/bb896653.aspx

The unique capabilities of Process Explorer make it useful for tracking down DLL-version problems or handle leaks, and provide insight into the way Windows and applications work. You can use it to see what % of the CPU is being devoted to DPCs that might be causing audio glitches.

http://www.focusrite.com/answerbase/article.php?id=265

Use the described tool to track down any devices on the PCI bus that have high PCI latency timer settings. The tool displays the current latency values for all expansion devices on the PCI bus and allows you to set the values manually. If you are experiencing clicks and pops and audio glitches on your PC and your graphics card or network card displays a high latency with this tool, try reducing the latency to 128 or 64 to stop hogging the bus. If you are using a firewire audio interface, you might also try increasing the Latency Timer value of your Firewire controller.

http://www.beyondlogic.org/solutions/processutil/processutil.htm

For end users needing maximum CPU cycles and RAM for audio, this free command line process utility can be used to create a batch file that kills all but necessary programs.

Tom White
AMP Alliance

Build this Programless USB Interface for MIDI instruments

Tom White — Thu, 29 May 2008 22:37:00 GMT

This article from EDN (Electronic Design News) describes how to use the FT-232BM from Future Technology Devices International (www.ftdichip.com), a USB-to-UART interface IC that you need not program, to interface a USB port to a MIDI bus.

http://www.edn.com/article/CA6549033.html

Tom White

AMP Alliance

Synth and Plugin SDKs

Tom White — Sat, 17 May 2008 21:12:00 GMT

Here are two resources for information on software synth and audio plugin APIs for Windows.

VST3 SDK Update - Mar 20 2008
	Steinberg announced an update to its VST3 SDK: The updated version is VST3.0.1, and is now available for download. The new version makes several additions to the initial release version of the VST3 SDK, as well as updated documentation. Developers downloading the new SDK should check the included Version History for a complete list of the additions.
Download Updated VST 3 SDK.

DXi SDK
	DXi is a DirectShow-based software synthesizer plug-in architecture, which combines audio DSP with MIDI event handling. MIDI effects (MFX) is a COM-based plug-in architecture designed for real-time processing of MIDI events in applications like SONAR. MFX was used to help extend DirectShow into what became the DXi architecture.
Visit DXi SDK Information Page at www.cakewalk.com.

Project Bar-B-Q 2008 Dates Announced

Tom White — Fri, 16 May 2008 21:08:00 GMT

The Thirteenth Annual Interactive Music Conference and BBQ will be held October 16-19, 2008, at Canyon of the Eagles Ranch, in Lake Buchanan, Texas.

The goal of Project Bar-B-Q is Influencing Music Hardware & Software Over the Next 5 Years.

To this end, a select group of hardware developers, software developers, audio engineers, composers, tech executives, and the like will all set aside their differences and spend two days of facilitated brainstorming to formulate some ideas and solutions. The result of this work is the annual BBQ report.

An Expensive Problem

Keeping pace with the rapidly changing computer audio business is no easy task, and countless dollars and man-hours depend on it. What individual has the required level of expertise in hardware, software, music, audio, marketing, the Internet, streaming and wireless technologies, IP, law, technical standards, business politics and entertainment fads to understand where computer audio was, is, and where it's going--let alone to influence it?

A computer can sound better than a movie theater. Why do we listen through low-bandwidth connections and tiny speakers? If audio can be half of a game's entertainment value, and the game industry makes more money than the film and TV industries combined, why is audio given less than one percent of a game's development resources? Why does something as technically simple as audio account for such a high percentage of computer crashes? How much do those crashes cost big businesses? How much time and self-esteem do they cost individual computer users? If all the little entertainment and productivity machines are going to "converge" into one big machine, won't that more complex machine tend to crash even more? And if the machines don't converge, but become rather a house full of single-function appliances, how can all the companies working on all the different types of audio make their systems work together without failing? Why are pirating issues such a big deal--why don't standard business models for music distribution exist? Why haven't we better leveraged the computer's ability to help us learn about music?

And before any of these questions are even answered, the entire industry and all of its issues are born anew when somebody says, "If a computer can sound that good, what kind of audio can we squeeze through a mobile phone?"

A Unique Solution

It's a tough situation, and to answer it, many of the movers and shakers of this industry reserve three days each October to attend a big-time Texas-style think-tank called "Project Bar-B-Q", held at the lodge at Canyon of the Eagles on Texas' beautiful Lake Buchanan.

The conference is hosted by The Fat Man, George Alistair Sanger, (www.fatman.com) who has been a Texas-Sized legend in game audio since 1983. It is operated by the colossal superstars of conference production Avallone Media Group, teamed with Sanger and his wife, Linda Law, who’s known by attendees as "Mission Control." Their mission statement, which has varied only slightly since the first BBQ in 1996, is nothing less ambitious than "Influencing Music Hardware and Software Over The Next 5 Years."

Radical Tactics

Unlike conventional meetings, BBQ shuns neckties, company logos, and fluorescent lights as detrimental to group thinking processes. BBQ uses natural catalysts to deepen and broaden thought: Attendees do their work under wide Texas skies. They sit around the fire on hay bales, eat top-notch food served up Western-Style, and are given lots of equipment for making music, as well as adequate structure for brainstorming.

The conference fee covers everything from the time attendees are picked up at the airport on Thursday until the time they are dropped back off on Sunday including registration, shuttle service, food, lodging, snacks and entertainment and more than likely a hat, bandana, bolo tie, and maybe even a branding iron.

Things move quickly at BBQ. The first evening and the morning of the second day, attendees are whipped into an intellectual frenzy by free-spirited debates, heavenly meals, inspirational talks, stories of BBQ's past successes, and a series of intentionally irrefutable challenges to the validity of anybody's preconceived agenda.

The "BBQ Brothers and Sisters," as they call each other, are not assigned a problem to solve. Instead, they form "The Giant Brain" and are challenged to do the first task that's impossible for an individual--to identify the four biggest questions/problems the industry faces. Once that's done, they split into four groups to find answers and solutions to the problems, with each attendee joining the group working in the area he finds most compelling. As a climax to the event, each group makes a presentation to the whole camp, and creates a report including action items that are expected by the community to benefit the industry.

It's been said that the power of the Big Brain is too mighty to predict, and not a good thing to try to limit or control too much. The BBQ staff is instructed that sometimes it's not so important what you do, but what you don't do.

As The Fat Man says to the group at the outset of the conference, "We don’t say ‘no’ to the Muses around here. If one sits on your shoulder and says, ‘Hey, you need to be sittin' on the porch with a cigar making deals with that Microsoft guy and that AMD guy!' you'd better damn well go do what you're inspired to do. If inspiration hits you, we’ll be proud to get the Hell out of your way." Inspired attendees are encouraged to step outside the structure of the working groups and form their own "rogue groups." With smaller numbers and intense inspiration, these groups often act as Special Forces units, and accomplish remarkable things.

www.projectbarbq.com

AES Announces International Conference on Audio for Games (Updated)

Tom White — Fri, 16 May 2008 20:43:00 GMT

UPDATE Aug 1, 2008:

The proposal for a dedicated conference on game-audio has been accepted by the AES Board of Governors. The conference will be held in London in February 2009 (tentatively 11th-13th Feb).

- Tom White

May 23, 2008: Michael Kelly of Sony Computer Entertainment Europe has been working with people in the game industry to put together a dedicated AES international conference on Audio for Games. He recently sent out the following request for information to AES Games Technical Committee members, and I thought some of you might want a heads-up about this interesting idea. If you want to know more, just email me and I'll see that you get in touch with Michael.

Tom White

AMP Alliance

AES Proposed International Conference on Audio for Games

Proposed Conference Location:

The conference will likely be held in London 2009. We currently have a growing membership in the US region and a healthy level of activity at US conventions. Attracting people to larger AES conventions in Europe is more difficult and it appears the European audience would prefer an event more focused on games. Whilst large conventions such as GDC are able to support dedicated technical tracks for audio, there is nothing that can offer this focus in Europe. Whilst the conference will be held in Europe, it will still be an international conference and we would encourage participation from all regions.

Proposed Conference Date:

The original date was planned for January 2009. Unfortunately there have been significant delays in finding the right venue. Although the AES normally expects proposals to be agreed at least 1 year in advance of the conference, we are now a little behind. Whilst we are now aiming for February 2009, the AES Board of Governors may prefer we postpone the conference. We're interested in feedback on alternative dates. The choice of January was originally to prevent clashes with any other conferences but also at a time when developers may have time to attend following the busy pre-Christmas period. We still feel this is a very strong reason to arrange the conference early in the year (now early February), but if we are asked to postpone the conference I would to hear your arguments for/against other dates. Basically, is early February a good date for you? Which other dates would you consider?

Schedule Conflicts:

For reference, here is a list of other conferences (large conferences such as GDC as well as local conferences which may clash). Please feel free to let me know if there are any other events that should be considered in this list.

* January: Netherlands Casual Games Conference (2008)

* March: GDC (23-27 2009, SF)

* April: Nordic GDC, AES (13-16 2009)

* May: AES Europe (17-20 2008), ION Washington (online conference 13-5 2008)

* June: SCEE DevStation (10-11 2008), Game Horizon (18-19 2008)

* July: Develop Brighton (29-31 2008), E3 LA (15-17 2008)

* August: AES (28-30 2009), GCDC Leipzig (20-24 2008), Edinburgh International Games Festival

* September: Austin GDC (15-17 2008), London Games Festival (2007)

* October: AES US (5-8 2008), Audio Mostly (22-23 2008, Sweden), Project BBQ (16-19 2008, Texas), Tokyo game show (9-12 2008)

* Novemember: GC Lyon (5-7 2008)

* December: Christmas & Game Deadlines

Regards

-- Michael Kelly, SCEE --

Introducing Myself (Tom White)

Tom White — Fri, 09 May 2008 22:55:00 GMT

Greetings, all AMP Alliance Members:

This is just a quick note to introduce myself. Many of you may already know me from my involvement with the MIDI Manufacturers Association (MMA), and/or the Interactive Audio Special Interest Group (IASIG). Now I'm helping Dan Moore to build the AMP Alliance into an association that provides services to, and represents the interests of Microsoft's partners in the music/audio development community.

AMP Alliance Objectives

As most of you know, the AMP Alliance was started primarily to improve access to information at Microsoft for developers of audio/music software, with the ultimate goal being to help grow the market for Windows audio/music apps and related products. What Dan and I would like to do is also explore other things that could be done by the group to grow the market, such as industry-wide promotions, consensus building, sharing resources, and more.

Over the next few weeks I will be contacting as many of you as possible to find out what kinds of services and information you would find most useful for improving, simplifying, and reducing the cost of your development efforts. I'm also interested in hearing about any promotional ideas that could benefit the industry as a whole, or might be opportunities for other AMP Alliance members.

AMP Alliance Web Site

Each AMP Alliance Partner Member is provided with a Partner Blog on the AMP Alliance web site, which we encourage you to use to promote your products, developer services, and anything else you think may be of interest to other developers. Our goal for the AMP Alliance web site is to be the premier portal for information about developing music and audio products for Microsoft platforms. Dan has already populated the site with some information, but we will find more.

If you've not had a chance to look at the site and upload your own content, please try and do so as soon as possible. It's important that the site helps developers work with each other, not just with Microsoft. If you have any problems posting your information, or have ideas for how to improve the site, please let me know. We're already planning changes to the site, and could use your feedback.

The AMP Alliance is your organization, and we need your input and involvement to make it valuable for you. Please feel free to contact me (or Dan) at any time with any requests, ideas, questions, etc.

Regards,

Tom White

twhite@ampalliance.org

Tom White

Vista SP1 and 24 Bit Audio

Troubleshooting Audio Performance Issues (Part 2)

More Audio Performance Tools and Tips

Audio Device Performance and Windows XP: Best Practices for Drivers

Windows Performance Tools Kit, v.4.1.1 (QFE)

Pigs Can Fly: Windows performance, development, and related issues

Troubleshooting Audio Performance Issues Part 1 (Updated)

Build this Programless USB Interface for MIDI instruments

Synth and Plugin SDKs

Project Bar-B-Q 2008 Dates Announced

AES Announces International Conference on Audio for Games (Updated)

Introducing Myself (Tom White)