amp MPEG audio decoder readme file (version 0.7.6) (C) Tomislav Uzelac 1996,1997 amp is free software and can be _used_ freely by anyone. If you want to do anything else with it, be sure to check the Legal section of this document for legal issues. THERE IS NO WARRANTY FOR THIS PROGRAM. Please check out the Legal section of this document. 1. Introduction 2. Installation 3. Running 4. Feedback 5. Contributing 6. Legal 1. Introduction amp (Audio Mpeg Player) is an MPEG audio decoder which I originally started putting together as a side project of the MPEG hardware design project at FER/Zagreb - just to confirm my knowledge of the standard. It works with both MPEG1 and MPEG2 audio streams (except for the multichannel extensions defined in MPEG2), layers 2 and 3. There is a gui for amp, written in Tcl/Tk by Edouard Lafargue. It is available at the amp home site ftp://ftp.rasip.fer.hr Another gui supported is the Sajber Jukebox, written by Joel Lindholm. The following people contributed their time and knowledge to amp: Karl Anders Oygard, Ilkka Karvinen, Lutz Vieweg, Dan Nelson, Edouard Lafargue, Andrew Richards, George Colouris, Dmitry Boldyrev, Andy Lo A Foe, Thomas Sailer, Justin Frankel amp home location is ftp://ftp.rasip.fer.hr/pub/mpeg/ and the mailing list: send 'HELP' in the body of the message to: multimedia@rasip.fer.hr If you want to find out more about MPEG, best places to start are http://www.mpeg.org http://www.mpeg2.de 2. Installation Installation should be simple enough if amp was ported to your system, just do a ./configure make You can edit the makefile further to suit your system. If configure fails to make a usable Makefile, you'll _have_ to edit it yourself. Linux users should try real-time playing support, as described in doc/realtime.txt. Some people that might pass on this feature are those with slower machines (i.e. 486's), or SMP systems (see the doc/linuxrealtime.txt file). Some versions of the linux C library produce an error when compiling amp with realtime support. A quick fix is to edit /usr/include/sched.h and replace _P in the offending line with __P. ./configure --enable-realtime make chown root.root amp chmod u+s amp ... this requires /dev/dsp to be both world readable and writeable. If you have a special group for people allowed to use the sound device (for instance, a group called sound), you can do a: chmod g+s amp or make your audio card world read/writeable (not recomended) chmod o+rw /dev/dsp* 3. Running: 'amp -h' gives you usage & options. If your computer is on the slower side, direct playback might not work, but you can decode it to .wav or raw pcm and play it later. 4. Feedback Send in your makefiles, opinions, bugreports, fixes; anything related to this program. You can also send me unlimited amounts of money, sugar, milk, etc. If you find any mpeg audio files that amp has trouble decoding, please tell me about this via e-mail . 5. Contributing Please contribute to amp. If you want to know what is going on in amp development, you can join the developers mailing list mpeg_audio_developers@rasip.fer.hr There are certain debugging facilities that I made in amp, but are disabled in the current release (they are neither nice nor user-friendly). If anyone enhances them (they are in dump.c) to the point that they're actually usable I'll be happy to include the changes in the release. I think this kind of debug output would be very useful to people studying these audio algorithms. 6. Legal This software can be used freely for any purpose. It can be distributed freely, as long as it is not sold commercially without permission from Tomislav Uzelac . However, including this software on CD_ROMs containing other free software is explicitly permitted even when a modest distribution fee is charged for the CD, as long as this software is not a primary selling argument for the CD. Building derived versions of this software is permitted, as long as they are not sold commercially without permission from Tomislav Uzelac . Any derived versions must be clearly marked as such, and must be called by a name other than amp. Any derived versions must retain this copyright notice. /* This license is itself copied from Tatu Ylonen's ssh package. It does * not mention being copyrighted itself :) */ THERE IS NO WARRANTY FOR THIS PROGRAM - whatsoever. You use it entirely at your risk, and neither Tomislav Uzelac, nor FER will be liable for any damages that might occur to your computer, software, etc. in consequence of you using this freeware program. Tomislav Uzelac