Bytebeat is a procedural [chiptune](chiptune.md)/8bit style music generated by a short expression in a programming language; it was discovered/highlighted in 2011 by [Viznut](viznut.md) (author of [countercomplex](countercomplex.md) blog) and others, and the technique capable of producing quite impressive music by single-line code has since caught the attention of many programmers, especially in [demoscene](demoscene.md). There has even been a [paper](https://arxiv.org/abs/1112.1368) written about bytebeat.
This is a [beautiful](beauty.md) [hack](hacking.md) for [LRS](lrs.md)/[suckless](suckless.md) programmers because it takes quite a tiny amount of code, space and effort to produce nice music, e.g. for [games](game.md) (done e.g. by [Anarch](anarch.md)).
8bit samples corresponding to `unsigned char` are typically used with bytebeat. The formulas take advantage of [overflows](overflow.md) that create rhythmical patterns with potential other operations such as multiplication, division, addition, squaring, bitwise/logical operators and conditions adding more interesting effects.
Bytebeat also looks kind of cool when rendered as an image (outputting pixels instead of musical samples).
Quick experiments with bytebeat can be performed with online tools that are easy to find on the [web](www.md), these usually use [JavaScript](javascript.md).
Nevertheless, traditionally we use [C](c.md) for bytebeat. We simply create a loop with a *time* variable (`i`) and inside the loop body we create our bytebeat expression with the variable to compute a char that we output.
A simple "workflow" for bytebeat "development" can be set up as follows. Firstly write a C program:
```
#include <stdio.h>
int main(void)
{
for (int i = 0; i <10000;++i)
putchar(
i / 3 // <bytebeatformulahere
);
return 0;
}
```
Now compile the program and play its output e.g. like this:
```
gcc program.c && ./a.out | aplay
```
Now we can just start experimenting and invent new music by fiddling with the formula indicated by the comment.
- Outputting the variable `i` creates a periodical saw-shaped beat, **multiplication/division decreases/increases the speed, addition/subtraction shifts the phase backward/forward**.
- Squaring (and other powers) create a **wah-wah effect**.
- Crazier patterns can be achieved by **using the variable in places of numerical constants**, e.g. `i << ((i / 512) % 8)` (shifting by a value that depends on the variable).
- Modulo (`%`) increases the frequency and **decreases volume** (limits the wave peak).
- So called **Sierpinski harmonies** are often used melodic expressions of the form `i*N & i >> M`.
- Bitwise and (`&`) can add distortion (create steps in the wave).
- A **macro structure** of the song (silent/louds parts, verse/chorus, ...) can be achieved by combining multiple patterns with some low-frequency pattern, e.g. this alternates a slower and faster beat: `int cond = (i & 0x8000) == 0;`, `cond * (i / 16) + !cond * (i / 32)`
- **Extra variables** can add more complexity (e.g. precompute some variable `a` which will subsequently be used multiple times in the final formula).
## Copyright
It is not exactly clear whether, how and to what extent [copyright](copyright) can apply to bytebeat: on one hand we have a short formula that's uncopyrightable (just like mathematical formulas), on the other hand we have music, an artistic expression. Many authors of bytebeat "release" their creations under [free](free_culture.md) [licenses](license.md) such as [CC-BY-SA](cc-by-sa.md), but such licenses are of course not applicable if copyright can't even arise.
The following more complex examples come from the [LRS](lrs.md) game [Anarch](anarch.md) (these are legally safe even in case copyright can apply to bytebeat as Anarch is released under [CC0](cc0.md)):
