*************************************************************************** * /\ * * /--\ * * |\ / /-------\ * * | \ | /---- : : | /-----\ |----\ /---- * * | \ | | | | | | | | | | * * | \ | |---- | ^ | | | | |____/ |---- * * | \ | | | / \ | | | | | \ | * * | \| \____ |/ \| \_______/ \_____/ | \_ \____ * * * * P R O D U C T I O N * * * *************************************************************************** Some information about UCDM - The Software Soundchip What is UCDM? ------------- UCDM is simply a standard for replayroutines, consisting of two parts, Players (UMP) and Feeders. A Feeder reads the songdata, translates it into sampleaddresses, volumes and frequencies with which it feeds the player, that makes the actual replay (the heavy bit). The idea is that every user shall be able to combine these two routines so it suits him the best. I have a large variety of players from 12.5 kHz 4 voice with no volume control taking approximately 12% CPU-time on a normal STE, to an 8 voice 25 kHz player taking approximately 95 % CPU-time. In the same way I can easily make different feeders ranging from normal Tracker- or Quartet-Feeders to EPSS lookalike MID-file-Feeders, thus being able to play all known songformats without having to rewrite the whole replayroutine. However, the only Feeder I've written so far is a CORESONG-Feeder (my own fileformat, more about this later), the Feeder in Octalyser is written by Code. How do I use UCDM in Octalyser? ------------------------------- Octalyser has a built a Feeder, so the only thing you have to do is to load the desired Player from the UCDM-menu and activate it. If you then play a module you will probably notice that toneslides sounds terrible. To make it sound better you simply increase the variable in the UCDM-menu marked 'TO' and then activate it again. The higher the value, the better will toneslides, tonevibratos and finetune-settings sound, but the more memory will the Player take if it uses a frequency-table (like Tammany). Why should I use UCDM in the Octalyser? --------------------------------------- The internal Octalyser replay routine is written to be flexible and take smallest possible amount of memory. My UCDM routines are more specialised and have therefore some other advantages and disadvantages. Tammany for example plays 8 voices in 25 kHz on a normal STE, with other words it's a lot faster than the internal routine. On the downside it takes a lot of memory and some calculations are a bit rough, which results in a slightly distorted sound (you will probably not notice it if you don't listen very carefully). If you are a Falcon-owner you should absolutely use the Players called Naishee and Banshee, that takes better use of Falcons increased resources. How do I use UCDM in my own programs? ------------------------------------- To use UCDM and Octalysermodules in your own programs you will need a Feeder that can read modules or CORESONG-files (modules can easily be converted to CORESONGs). If you register Octalyser, we will send you a CORESONG-Feeder, a Module-to-CORESONG-converter and one or two more UCDM-Players (among them Rachel, the fast 12.5 kHz player). Why we use our own fileformat is that it is more compact than a module (the songdata (not samples) takes about 20 % of it's original size) and that we want to put the song and samples in two different files, so you can have more than one song in your program using the same samples. You will, of course, also receive a simple example-source in assembler (if demand is high enough we can also fix examplelistings in STOS GFA-Basic, C or Pascal). Information about the UCDM-Players ---------------------------------- Here follows some technical information about the UCDM-Players supplied with Octalyser. All CPU-time is referred to a standard STE if nothing else is stated. TERMODY - This is a 50 kHz Player taking approximately 55% CPU-time. I want to point out that this is a REAL 50 kHz Player and not a 25 kHz Multiplexer (like in Protracker). However, in order to make it that fast I have used some techniques that unfortunately distorts the sound a bit. This Player will in most cases sound better than the internal 25 kHz Anti- Alias-Replayroutine, but in some cases it doesn't. You simply have to hear for yourself and see which sounds best to which module. In addition to that it really EATS memory! A good hacker named Lance has found out a way for me to decrease the memory consumption to 10 % of the original AND speed it up, but unfortunately I haven't had time to implement it yet. It doesn't run on Falcon. It does not support CIA-timing and it doesn't sound so good if you run it with 60 Hz screenupdate. One more thing: TERMODY IS DESTRUCTIVE! It converts the samples to 7 bits before playing. So only use TERMODY to listen to modules after having saved them! TAMMANY - This is a 25 kHz Multiplex 8 voice Player taking a maximum of about 95% CPU-time, but it varies a lot depending on the amount of voices actually playing and effects in use. It takes about half the amount of memory that TERMODY does. It distorts the sound a bit, but much less than TERMODY, making it almost impossible to hear (you can only hear it on some very special sounds and then you have to listen carefully). Falconcompatible and uses the blitter. Because of this, it will make the lower border flicker when playing in Octalyser with 60Hz screenupdate. Does not support CIA-timing. NAISHEE - Is a 4 channel 16-bit 50 kHz Falcon-only player. Since I can't program the DSP yet, this runs on the 68030, taking nearly half it's processortime. The reason that it's this slow is that I have used the slowest kind of replayroutines in order to increase the replayquality as high as possible. It doesn't distort the sound at all and the 16-bit output makes sure that it takes use of all eight bits of the samples even when playing at low volume. Supports CIA-timing. Takes almost no memory at all. BANSHEE - This is an 8 voice version of NAISHEE. It's slow, but plays eight voices at highest possible quality. NIKITA - This is a slow 25 kHz multiplex, 4 voice Player taking nearly no memory at all. No distortion either. It should give the same soundquality as the internal player. The only difference is that this uses multiplex instead of Anti-Alias, so all of you that have argued about which method gives the best quality can now make comparisons. The reason I wrote this is that there absolutely is need for a normal allround-player for gameintros etc. Falcon compatible. And to all of you that wonder why I name the players like this I have no good answer except that it's easier to talk about 'NIKITA' than 25KHZM4V.UMP and that I give them names that I like. If anybody out there is interested in writing UCDM Players and/or Feeders, then feel free to contact me for information. The converters and feeders for CORESONG are NOT completed yet. They are functional but still under development, why users might have to wait a while for these files after registration. If somebody out there want to write UCDM-Players for the Amiga or Macintosh in order to create a standard (would be useful when converting games between platforms) they are very welcome to contact me. IMPORTANT! We have recently found some kind of bug in Naishee and Banshee! Unfortunately I haven't been able to locate and correct it (it's really strange!) so they might crash the computer all of a sudden when using them! I really recommend composers to make regular back-ups when using them until I have supplied a safe version. Happy UCDM-using out there! Best wishes Tord Jansson ( Blade of New Core )