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- Short: Retargetable audio v4.15, User's Archive
- Type: mus/misc
- Author: Martin Blom <lcs@lysator.liu.se>
- Uploader: Martin Blom <lcs@lysator.liu.se>
-
- This archive contains the binary distribution of AHI,
- everything you need to use programs that require AHI,
- and documentation in AmigaGuide® format.
-
- Changes since last release
- ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
- Bug fixes in the device code.
- Updated documentation.
- New translation (hrvatski).
- Added driver for Maestro Pro to the distribution.
-
-
- TITLE
-
- AHI Audio system
-
- VERSION
-
- Release 4
-
- AUTHOR
-
- Martin Blom <lcs@lysator.liu.se>
-
- DESCRIPTION
-
- Retargetable Audio for AmigaOS
- ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
-
- (When refering to this software, the correct term is
- 'AHI audio system' or just 'AHI', never 'Audio Hardware
- Interface'! 'AHI' is pronounced 'atchii', as in 'God bless!'.)
-
- Starting with version 3 of AHI, the MC68000 processor is also supported.
- However, many features are lacking:
-
- · Very limited volime control when using 16 bit samples
- · No HiFi mixing routines are available.
- · No stereo samples
- · No DSP effects are available.
- · Less precision on some calculations
- · Slower
-
- As you can see, this version is very primitive. Get yourself an
- accelerator! I cannot guarantee that I will continue to support this
- processor in the future.
-
- Quick overview
- ¯¯¯¯¯¯¯¯¯¯¯¯¯¯
-
- * Driver based
-
- Each supported sound card is controlled by a library-based audio
- driver. For a 'dumb' sound card, a new driver should be written in
- a few hours. For a 'smart' sound card, it is possible to utilize an
- on-board DSP, for example, to maximize performance and sound quality.
- For sound cards with own DSP but little or no memory, it is possible
- to use the main CPU to mix channels and do the post-processing
- with the DSP. Available today are drivers for
-
- · Aura (sampler only)
- · Clarity (sampler only)
- · Delfina DSP and Delfina Lite
- · DraCo Motion
- · Maestro Pro
- · Melody MPEG
- · Paula (8/14/14c bit)
- · Prelude
- · Toccata
- · Wavetools
- · 8SVX (mono) and AIFF/AIFC (mono & stereo) sample render
-
- * Fast, powerful mixing routines (yeah, right... haha)
-
- The device's mixing routines mix 8- or 16-bit signed samples, both
- mono and stereo, located in Fast-RAM and outputs 16-bit mono or stereo
- (with stereo panning if desired) data, using any number of channels
- (as long as 'any' means less than 128...). Tables can be used speed
- the mixing up (especially when using 8-bit samples). The samples can
- have any length (including odd) and can have any number of loops.
-
- * Support for non-realtime mixing
-
- By providing a timing feature, it is possible to create high-
- quality output even if the processing power is lacking, by saving
- the output to disk, for example as an IFF AIFF or 8SXV file.
- There are so-called HiFi mixing routines that can be used, which
- use linear interpolation and gives 32 bit output.
-
- * Audio database
-
- Uses ID codes, much like Screenmode IDs, to select the many
- parameters that can be set. The functions to access the audio
- database are not too different from those in 'graphics.library'.
- The device also features a requester to get an ID code from the
- user.
-
- * Both high- and low-level protocol
-
- By acting both like a device and a library, AHI gives the programmer
- a choice between full control and simplicity. The device API allows
- several programs to use the audio hardware at the same time, and
- the AUDIO: dos-device driver makes playing and recording sound very
- simple for both the programmer and user.
-
- * Future Compatible
-
- When AmigaOS gets device-independent audio worth it's name, it should
- not be too difficult to write a driver for AHI, allowing applications
- using 'ahi.device' to automatically use the new OS interface. At
- least I hope it wont.
-
- SPECIAL REQUIREMENTS
-
- AmigaOS release 2.
- MC68020 processor strongly recommended.
-
- AVAILABILITY
-
- Aminet, for example:
- ftp://ftp.germany.aminet.org/pub/aminet/dev/misc/ahidev.lha
- ftp://ftp.germany.aminet.org/pub/aminet/mus/misc/ahiusr.lha
- ftp://ftp.germany.aminet.org/pub/aminet/docs/misc/ahiman.lha
-
- WWW:
- http://www.lysator.liu.se/~lcs/ahi.html
-
- PRICE
-
- Free. But if you use it in a shareware of commercial product,
- I would like a registered copy for me and each of the audio driver
- authors (this is merely a wish, you don't have to do it if you don't
- think we deserve it). See the AHI User's Guide for more information.
-
- DISTRIBUTABILITY
-
- Copyright ©1994-1997 Martin Blom.
- Freely distributable in unmodified form.
- See the AHI User's Guide for more information.
-