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- Short: Retargetable audio v4, Doc. Archive
- Author: Martin Blom <lcs@lysator.liu.se>
- Uploader: Martin Blom <lcs@lysator.liu.se>
- Type: docs/misc
-
- This archive contains the documentation for AHI (both
- AHI Developer's Guide and AHI User's Guide) as DVI,
- Postscript and HTML files.
-
- AmigaGuide® versions are included in the AHI Developer's
- archive and the AHI User's archive.
-
- 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:
-
- · 16 bit samples are converted to 8 bits before they are mixed.
- · 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)
- · Delfina
- · DraCo Motion
- · 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.
-
-
- ============================= Archive contents =============================
-
- Original Packed Ratio Date Time Name
- -------- ------- ----- --------- -------- -------------
- 4732 2206 53.3% 23-Apr-97 09:20:26 +ahiman.readme
- 92004 22296 75.7% 21-Apr-97 23:45:26 +ahidev.dvi
- 63652 18606 70.7% 21-Apr-97 23:43:40 +ahiusr.dvi
- 3553 1380 61.1% 21-Apr-97 23:48:34 +ahidev_1.html
- 6654 2468 62.9% 21-Apr-97 23:48:38 +ahidev_10.html
- 1866 834 55.3% 21-Apr-97 23:48:38 +ahidev_11.html
- 2878 1147 60.1% 21-Apr-97 23:48:38 +ahidev_12.html
- 2928 1099 62.4% 21-Apr-97 23:48:40 +ahidev_13.html
- 5430 2072 61.8% 21-Apr-97 23:48:40 +ahidev_14.html
- 1110 464 58.1% 21-Apr-97 23:48:40 +ahidev_15.html
- 1812 729 59.7% 21-Apr-97 23:48:40 +ahidev_16.html
- 1863 827 55.6% 21-Apr-97 23:48:40 +ahidev_17.html
- 3655 988 72.9% 21-Apr-97 23:48:40 +ahidev_18.html
- 1222 460 62.3% 21-Apr-97 23:48:42 +ahidev_19.html
- 2452 1141 53.4% 21-Apr-97 23:48:34 +ahidev_2.html
- 1428 479 66.4% 21-Apr-97 23:48:42 +ahidev_20.html
- 2754 726 73.6% 21-Apr-97 23:48:42 +ahidev_21.html
- 1165 532 54.3% 21-Apr-97 23:48:36 +ahidev_3.html
- 1727 764 55.7% 21-Apr-97 23:48:36 +ahidev_4.html
- 1818 767 57.8% 21-Apr-97 23:48:36 +ahidev_5.html
- 3118 1227 60.6% 21-Apr-97 23:48:36 +ahidev_6.html
- 2723 1074 60.5% 21-Apr-97 23:48:36 +ahidev_7.html
- 6138 2169 64.6% 21-Apr-97 23:48:38 +ahidev_8.html
- 3329 1436 56.8% 21-Apr-97 23:48:38 +ahidev_9.html
- 774 459 40.6% 21-Apr-97 23:48:34 +ahidev_foot.html
- 3751 1169 68.8% 21-Apr-97 23:48:34 +ahidev_toc.html
- 3586 1618 54.8% 21-Apr-97 23:47:22 +ahiusr_1.html
- 1153 522 54.7% 21-Apr-97 23:47:24 +ahiusr_10.html
- 1141 477 58.1% 21-Apr-97 23:47:24 +ahiusr_11.html
- 933 390 58.1% 21-Apr-97 23:47:24 +ahiusr_12.html
- 1948 863 55.6% 21-Apr-97 23:47:24 +ahiusr_13.html
- 2220 1040 53.1% 21-Apr-97 23:47:24 +ahiusr_14.html
- 4418 1819 58.8% 21-Apr-97 23:47:24 +ahiusr_15.html
- 1464 591 59.6% 21-Apr-97 23:47:24 +ahiusr_16.html
- 2512 1117 55.5% 21-Apr-97 23:47:26 +ahiusr_17.html
- 2646 1170 55.7% 21-Apr-97 23:47:26 +ahiusr_18.html
- 1395 594 57.4% 21-Apr-97 23:47:26 +ahiusr_19.html
- 2505 1149 54.1% 21-Apr-97 23:47:22 +ahiusr_2.html
- 2248 1085 51.7% 21-Apr-97 23:47:26 +ahiusr_20.html
- 1405 614 56.2% 21-Apr-97 23:47:26 +ahiusr_21.html
- 2128 989 53.5% 21-Apr-97 23:47:26 +ahiusr_22.html
- 1933 917 52.5% 21-Apr-97 23:47:26 +ahiusr_23.html
- 1388 568 59.0% 21-Apr-97 23:47:26 +ahiusr_24.html
- 3970 1091 72.5% 21-Apr-97 23:47:28 +ahiusr_25.html
- 1271 610 52.0% 21-Apr-97 23:47:22 +ahiusr_3.html
- 1130 454 59.8% 21-Apr-97 23:47:22 +ahiusr_4.html
- 2318 1044 54.9% 21-Apr-97 23:47:22 +ahiusr_5.html
- 2460 1032 58.0% 21-Apr-97 23:47:22 +ahiusr_6.html
- 994 375 62.2% 21-Apr-97 23:47:22 +ahiusr_7.html
- 1437 635 55.8% 21-Apr-97 23:47:22 +ahiusr_8.html
- 1182 479 59.4% 21-Apr-97 23:47:22 +ahiusr_9.html
- 2038 1061 47.9% 21-Apr-97 23:47:20 +ahiusr_foot.html
- 2282 796 65.1% 21-Apr-97 23:47:20 +ahiusr_toc.html
- 214409 81555 61.9% 21-Apr-97 23:46:14 +ahidev.ps
- 172415 68461 60.2% 21-Apr-97 23:45:56 +ahiusr.ps
- -------- ------- ----- --------- --------
- 665465 240635 63.8% 23-Apr-97 17:32:48 55 files
-