Short: Anti-alias resampling for RAW 8SVX sound v1.11 Author: Björn Östberg Uploader: Björn Östberg Version: 1.11 Type: mus/edit Rescale Version 1.11 Copyright ©1999 Björn Ösberg Usage: Rescale SourceRate DestRate ReplayRate Or: Rescale SourceRate DestRate SourceRate Programming: Björn Östberg (JetRacer@Hem.Passagen.se) Additional Code By: Fredrik Rambris (Fredrik.Rambris@Amiga.nu) HomePage: www.Amiga.nu Rescale v1.11 68020 and 68020/68882 versions are included in this archive. --------------------------------------------------------------------------- Disclaimer: The programmer can't be held responsible for any damages caused by this program - use it at your own risc! No distribution fee whatsoever can be charged for the archive nor it's contense (Aminet have exclusive right to distribute this archive and charge whatever fee they seem suitable). The archive must be distributed in it's original shape without any modifications. --------------------------------------------------------------------------- Rescale is a resample utility (SHELL only) which resamples standard 8SVX raw sounds. The resample method used in the Rescale utility is vector based scaling -similar to the one used in sizeable fonts but with antialias features. Running Rescale without any statements or faulty syntax will make it type out some instructions aswell as copyright and version info. There are no restrictions when it comes to setting the samplerate so be carefull. A nice side-effect of the previus is that you can specify the relation between source/dest in any way you like: Downsample relative 1:2 with 44.1KHz with replay rate Rescale 1 2 44100 Downsample period 127 to period 254 -no replay rate Rescale 127 254 127 Etc. Rescale can actually be used to rescale any signed 8-bit raw datafile at all. -Usefull for programmers who wants to rescale sinus tables, etc. with very high quality. In practic ¯¯¯¯¯¯¯¯¯¯ -That sounds nice but what does it all mean? Well, f.ex. that you can resample finetune without any hearable quality loss (Unlike X-Tracker, OctaMED X, AudioMaster X, etc.). You can also downsample with insane rates as 1:4 or below without jitter (with reservations for the 8-bit format itself) or a totall loss of treble (no digital filters). Quality loss ¯¯¯¯¯¯¯¯¯¯¯¯ If you have resampled chords in protracker (or whatever) you know that it sound crappy. What most people don't know is why: With probably no exceptions the sample editors/converters and composer programs of today all use the classic integer-based skip/duplicate or skip/mix resample methods. The quality loss that these produce is very high due to the fact that the quantization timing error increase drasticly. Or in laymans terms: it produces transient noise and static tuning errors. About the programmer ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ I (Björn Östberg) created the Rescale utility as an exersize learning ANSII-C. Have no fear -An experienced programmer and friend of mine (Fredrik Rambris) had a peek at the source before I released it and he had no objections whatsoever. He also helped me out with the AmigaOS filehandling (since ANSII-C filehandling sucks!) and memory allocation using Exec. The rescaling rutine is small enough to be rather harmless so that rules out most error sources. I also have extencive experience with the programming language Basic aswell so I'm no real freshman programmer. In the near future (before Y2K -hopefully): ·IFF 8SVX support -Have to hunt some specs. ·AIFF support -Within months ·AIFF-C support -Same here. Hate Apple for not releasing (de)compression code -not everybody can use Soundmanager you know. ·Wav/RIFF support -Within months ·Boopsi GUI -Have to learn some more... ·Multichannel support -Stereo within months, multi Y2K or never. ·8/16/24/32-bit support -Within months History: v1.11 99-05-05 (Current) First release. Small bugfix: Minor UI errors... Major Aminet upload problems due to lack of initiative =) v1.1 99-04-09 Bugfix: Fixed a defect statement causing the help text to be typed no matter if the user syntax was correct or not. Fixed minor bugs; some spell errors, etc. Wrote ReadMe files, compressed AmiNet LHA Archive, and such. The utility was created and converted within six days. v1.0ß 99-04-08 Added the help text to the main. v0.9 99-04-08 Completed Basic convertion. Got some help with AmigaOS filehandling & arguments parsing, aswell as memory allocation using Exec. v0.8 99-04-07 Did most Basic convertion, compiles just fine -the program doesn't do anything usefull yet though. v0.7 99-04-05 Re-arranged the scaling routine written in Basic to a procedure, added requesters and simple error handling. v0.6 99-04-03 Wrote a scaling routine in Basic within 10 minutes. Was in a state of shock the rest of the day since the routine worked at the first try (almost) and only produced a guru once ;-) For those of you with CD-R: I'm also working on an ultra qualitative Protracker mod-to-sample music rendering program -using this very scaling routine and other cool stuff. Much can be done to improve the quality of non-realtime protracker rendering. Floatingpoint everywhere (almost). Floatingpoint volume slide routines -updates the amplitude for every single sample, etc. I'm a reverb nut so I think I'll just throw in my reverb routine aswell (4-256 channels highly qualitative reverb). Natually I will support AIFF, AIFF-C, WAV & RAW signed/unsigned 8/16/24/32-bit - aswell as a stereo surround audiomode (reverb). Note: This one is still vaporware. For musicians and nirds: Ontop of the previus I'm co-working on a sample editor/creator/sampler/ mixer/ etc. program called Soundfactory®. REAL cool stuff. Advanced synthetics, advanced reverb, digital equalizer, advanced proffesional editing tools, professional multichannel editing and mixing, direct HDD edit with disk cache, HDD recording through AHI, maybe even a full tracker composer, all within a single program. Really advanced programming style: main executable is hosting external processing/gui/functionallity modules. Fault tolerant design, etc. On what platform? AmigaOS! When? Our goal is before Y2K, but we will probably break that deadline. This one is NOT vaporware - development in progress... Björn Östberg SpEEd Productions Site: http://www.Amiga.nu -Soundfactory® Development News ============================= Archive contents ============================= Original Packed Ratio Date Time Name -------- ------- ----- --------- -------- ------------- 6638 3104 53.2% 14-May-99 19:33:12 Rescale.readme 7996 4958 37.9% 05-May-99 20:58:54 Rescale_020 7672 4833 37.0% 05-May-99 20:53:38 Rescale_020FPU -------- ------- ----- --------- -------- 22306 12895 42.1% 15-May-99 20:51:50 3 files