1use sva_core::DEFAULT_STORE_BYTES;
4use sva_core::solve;
5use sva_engine::resample;
6use sva_engine::{
7 DEFAULT_BUFFER_SECS, DEFAULT_CELL_SECS, DEFAULT_FLOOR_DB, DEFAULT_FRAME_SECS,
8 DEFAULT_LEDGER_DEPTH, DEFAULT_LOUDNESS_WINDOW_SECS, DEFAULT_MAX_PAIRS, DEFAULT_MAX_PEAKS,
9 DEFAULT_MODULATION_WINDOW_SECS, DEFAULT_NOVELTY_WINDOW_SECS, DEFAULT_OVERSAMPLE,
10 DEFAULT_PARTIALS_FLOOR_DB, DEFAULT_PARTIALS_FRAME_SECS, DEFAULT_PARTIALS_HOP_SECS,
11 DEFAULT_PARTIALS_TRACKS, DEFAULT_PARTIALS_WINDOW_SECS, DEFAULT_PERIODICITY_WINDOW_SECS,
12 DEFAULT_SAMPLE_RATE, DEFAULT_SMOOTH_SECS, PSYCHOACOUSTIC_V1, READINGS, Reads,
13 self_similarity::MAX_CELLS, spectrum,
14};
15
16pub fn help_text() -> String {
19 let bits = PSYCHOACOUSTIC_V1.precision_bits;
20 let store_gb = DEFAULT_STORE_BYTES >> 30;
21 let body_chars = crate::lint::BODY_CHARS;
22 let representations = representations();
23 let (min_frame, max_frame) = (spectrum::MIN_FRAME, spectrum::MAX_FRAME);
24 let rules = solve_rules();
25 let floor = solve::FLOOR_DB;
26 let (max_renders, step_tol, cost_tol) = (
27 solve::DEFAULT_MAX_RENDERS,
28 solve::DEFAULT_STEP_TOL,
29 solve::DEFAULT_COST_TOL,
30 );
31 let (passband, stopband) = (resample::PASSBAND, resample::STOPBAND);
32 let bound = format!("{} dB", 20.0 * resample::BOUND.log10());
33 let formats = crate::recording::READS
34 .map(|e| format!("`.{e}`"))
35 .join(", ");
36 let unreadable = crate::recording::UNREADABLE;
37 format!(
38 r#"USAGE:
39 sva-cli (render | analyze | solve | lint | trace | builtins | outline | new) [arguments]
40
41DESCRIPTION:
42 A composition is a directory of node files, each one closed-form expression in
43 `t` or `f` on one line, or a score placing notes in time. sva-cli reads that
44 composition and prints what it is and what it sounds like, as JSON on stdout.
45 `render`, `solve`, `lint` and `trace` read the current directory; `new` writes
46 beside it and `analyze` reads a file. `solve` fits variables to a reference.
47
48SCORES:
49 A score is a `.jsonl` file: JSON Lines, one object per line, sorted by `at`;
50 `@score/drop` reads `score/drop.jsonl`, and a ref never writes `.jsonl`. A
51 file with no extension opening with `{{` refuses with the rename. Line 1 is
52 its annotation, the doc comment's four fields, which `lint` holds it to:
53 {{"annotation": "Models: ... | Neglects: ... | IO: (t) -> amplitude | Tags: ..."}}
54 Every other line is one kind, told by its keys, and may add `"comment"`:
55 event "at", "node", "deg", "len" and the node's parameters: plays it
56 mark "at", "mark": a point `mark(name)` reads in this file's times
57 comment "at", "comment": a note to the reader at a time
58 move "at", "lane", "to", and "node", "len", "shape" where written
59 A score lowers to equations, the sum of its events in written order, each
60 its node shifted to its `at`; marks, comments and moves sound nothing.
61 at a time string, "0.25b" or "0.5s", or arithmetic over times, "2b +
62 1b/3" for a triplet; a bare number has no unit and refuses. A file
63 counts every time in bars or every one in seconds. "mark(verse) -
64 2b" is a position, "mark(drop) - mark(build)" a duration.
65 node an `@ref` from the score's own directory: a sound, an equation or
66 another score. On a line placing a score `len` crops it there and
67 nothing else binds; a `node` list mixing scores and sounds refuses
68 `len`.
69 deg a whole scale degree counted from 1, the tonic: sugar for "f0":
70 "deg(n)". In a seven-row scale 8 is the tonic an octave up, 0 the
71 seventh below and -6 the tonic an octave down. A chromatic note
72 binds "f0": "deg(7)*1st"; a line writing both refuses.
73 len a time as `at` takes, bound as the node's `len`.
74 other binds the node's parameter of that name: a number, or a constant in
75 a string, "0.03s", "-6db", "900hz", "A1", "0.8*0.9", "deg(5)/2".
76 Any field but `comment` may be a list. A line listing N items is N events,
77 moves or marks, item i of every list going to the i-th and a single value to
78 all; lists of different lengths refuse. A chord is a `deg` list on one `at`:
79 {{"at": "0b", "node": "@../instruments/keys", "deg": [1, 3, 5],
80 "vel": [0.8, 0.5, 0.6]}}
81 `deg(n)` is the tonic in `variables/key` times degree n's ratio in the scale
82 `variables/scale` names, read where the line sits, in a score or in any
83 equation. A scale is one the language names, as `minor` or `dorian` (`sva-cli
84 builtins` lists each with its cents), or a file of one row per degree in cents
85 above the tonic, ascending, the last the period, named by a ref: a file
86 `scales/custom` holding 200 400 500 700 900 1100 1200 is the major scale. A
87 value reading `t` or a `@ref`, a field the node does not read, a parameter it
88 reads that nothing binds, and a `deg` with no scale refuse before any audio,
89 each naming the score's file, line and column.
90
91 A lane is one value moving through the song: a node's parameter, a move
92 naming "node" and "lane": "cutoff", or a variable under `variables/`, a move
93 naming "lane" alone: "energy", "key", "scale", "bpm" (never "meter"). A move
94 with no `len` sets the lane at `at`; with "len" and "shape", `lin` or `exp`,
95 it ramps there from the value it holds:
96 {{"at": "24b", "node": "@../instruments/saw", "lane": "cutoff",
97 "to": "9khz", "len": "8b", "shape": "exp"}}
98 {{"at": "72b", "lane": "key", "to": "key*2st", "comment": "a tone up"}}
99 {{"at": "92b", "lane": "bpm", "to": "bpm*8/9", "len": "4b", "shape": "lin"}}
100 A `to` naming the lane means its home value, the node's default or the
101 variable's file, so it follows `--set`. A lane reaches every instance of its
102 node, from a score or an equation, inside a wrapper too, unless the line or
103 an invoking equation passes that parameter, which wins. Where it holds one
104 value over an instance's span it binds that number; where it moves there the
105 instance reads it at its song time, and where the engine refuses a moving
106 value, such as `sat`'s `drive`, the move refuses as `bad-lane`: pass a
107 constant, move the lane between notes, or close the sound's tail with a crop.
108 A score's times ride the tempo curve the `bpm` lane draws; `b` in an equation
109 stays a bar of `variables/bpm`. A song places its sections at marks:
110 {{"at": "0b", "mark": "intro"}}
111 {{"at": "mark(intro)", "node": "@intro"}}
112 {{"at": "mark(intro) + 8b", "mark": "verse"}}
113 {{"at": "mark(verse)", "node": "@verse"}}
114 `concat` and `repeat` place parts on the curve too: `repeat(@score/riff-1b, 4)`.
115 An equation reading a score at `t - d`, an echo or a send, hears the song as
116 it was d earlier: its lines keep their song time, and a move however many
117 reads reach it is one move.
118 A control score is one no sounding score places, read by an equation as a
119 signal: `@score/song(t) * (1 - @score/pump(t))` ducks the song under it.
120 `sva-cli outline @score/song` prints a song's marks, tempo, lanes, events and
121 size. Lint and render warn of a line passing a parameter whose lane ramps
122 under it (`line-overrides-lane`), and of a lane no instance reads
123 (`lane-reaches-nothing`).
124
125RESERVED VARIABLES:
126 Four nodes under `variables/` are reserved: a ref reads one like any node,
127 and a bar or a degree reads one by name:
128 variables/bpm a number, the beats per minute: 120
129 variables/meter beats per bar over the note: 4/4
130 variables/key the tonic `deg` counts from, a note or hertz: C3
131 variables/scale the scale `deg` counts in, a built-in's name: major, or a
132 ref to a scale file: @../scales/custom
133 A `b` literal or a file's `-2b` span reads bpm and meter; a `deg(n)` reads key
134 and scale. Before anything renders, each read is replaced by its value, by one
135 pass for all four: a bar becomes `n*(beats*60/bpm)` seconds and `deg(n)`
136 becomes `@variables/key` times degree n's ratio, the tonic still a ref. A
137 read with no value to replace it refuses as `bad-tempo` or `bad-scale`, as
138 does a variable holding no such value, such as bpm without meter, or a
139 scale name no built-in has, which refuses listing every built-in. A stream's
140 edit to a variable, or to the scale file it names, replaces every read of it
141 again. A node elsewhere named `bpm` is an ordinary node. Any other file under
142 `variables/`, as `variables/energy` holding 0.5, is a variable of the
143 composition's own: a ref reads it, `--set` sets it, and a score's moves move
144 it, as they move the reserved ones but `meter` (SCORES).
145
146RENDER:
147 sva-cli render '<expression>' --representation <list> [--until '<condition>']
148 [--bits <n>] [--rate <hz>] [--threads <n>] [--cache <path|none>]
149 [--set <name>=<text>]... [--confirm]
150
151 Renders one expression, in the grammar a node file's body uses, and prints one
152 reading per representation under `data.representations`. `@path` reads a node
153 from the current directory and `@/abs/path` one anywhere; there is no default
154 target. Every reading states what it was read with: `representation`, its
155 name, and `args`, every argument it takes as it used it, a plain number as a
156 number and the rest as `--representation` spells them (`pitch` alone prints
157 `"peaks": 16, "frame": "50ms"`), a default written out and a `spectrum`
158 frame left to fit the range as the frame it fitted. Null is an argument that
159 did not apply: a frame read exactly off the math, `modulation`'s unwritten
160 `bpm`, `samples`' `buffer` with no device. Its `args` written back as
161 `name(key=value, ...)`, nulls left out, ask the same reading. It states its
162 `source` (exact or measured), the conformance profile it ran under, and its
163 rate; `analyze` prints the same.
164
165 The target's own ref may read an interval: `@piano4([0, 2b], f0=C4,
166 vel=0.5, release=1s)`, where `release` is the instrument's own parameter. Its ends are the language's literals (`s`, `ms`, `b`,
167 `sp`, or a bare `0`); `[a, inf)` and `[a,)` leave the end open; the other
168 arguments are the node's own named ones. The start trims the output alone:
169 history before it is still computed, so a loop or a filter carries the state
170 it had there. With no interval the render starts at 0, earlier only where a
171 crop reaches before it, and its end is open. Inside an expression a window is
172 a `crop`. A target that samples its one ref read, `sample(@piano4([0, 2b],
173 f0=C4))`, reads that ref's interval and binds and the same node values.
174
175 `sample("<path>")` is a recording: a file relative to the directory sva-cli
176 runs in, or absolute, read as `analyze` reads one (ANALYZE); keep it outside
177 the composition, where it would be read as a node. It is the file's samples
178 at the render's rate, one component per channel as `join` makes them, silent
179 outside the file's span. At its own rate every sample passes unchanged. At
180 another a cos^16-windowed sinc reads it: a tone up to {passband} of the lower
181 rate reads within {bound} of itself, and one from {stopband} of it at most
182 {bound} of its level, a bound proven for the kernel that the label states
183 under `resampled` beside the rate it came from. The path is the language's
184 one string, in double quotes and only as `sample`'s one argument; one naming
185 no file refuses as `not_found`, and one `analyze` cannot read as
186 `{unreadable}`. A store keys a recording by its samples and rate, never its
187 path.
188
189 Every node is computed over its support met with what reads it, and nowhere
190 else: outside its support a node is exactly zero. A closed interval renders
191 exactly its length, nothing cut. An open one ends where the root's support
192 does: a crop's end, the exact underflow of an `exp`, a clamp holding a factor
193 at zero; or earlier, where a proven upper bound on the root's magnitude stays
194 under the profile's silence threshold (-120 dBFS) from a sample on. A root
195 with no such bound (a held sine, a loop) is never cut. The label's `pruned`
196 states the threshold as `db` and the root's cut, `from` the sample the render
197 is treated as silent from. A stream's term leaves `@notes` where its support
198 ends. An open interval over a root whose support never ends and is never cut
199 (a held sine, a physical solver) refuses as `render.no_end`. A short-time
200 transform reads its input whole, and refuses one with no end as
201 `engine.unbounded_extent`. A form in `f` with no dual in `t` has no samples
202 and refuses as its dual does, `cast.left_algebra`.
203
204 A render is a stream pulled to its end: a closed form, a short-time
205 transform and what either reads are computed over their whole extent first,
206 and every other node block by block. `--until '<condition>'` stops the render
207 at the first sample the condition holds at, or at the interval's end,
208 whichever is first. It is checked as each block is pulled, so no node driven
209 block by block runs past the block it holds in. A condition compares (`<`,
210 `<=`, `>`, `>=`) `t`, `envelope(t)` (the RMS over every channel of the
211 `envelope` representation's frame holding `t`, framed by its own `frame`
212 where one is asked) and literals, joined by `and`/`or`.
213
214 `--representation <list>` takes a comma list of readings and may repeat. Each
215 is a call in the language's own syntax, its options its named arguments:
216 `spectrum(peaks=8, frame=50ms)`, `ledger(depth=3, brief=1)`. A `frame`,
217 `window`, `cell` or `smooth` is a time as a score writes one, in seconds,
218 `50ms`, or in bars, `1b/8` (`1/8b` is one over eight bars), a bar lasting
219 what the render's tempo says; where none is known, as in `analyze`, bars
220 refuse as `tempo.invalid_bpm_meter`. An entry
221 followed by `=<path>` writes a file instead, listed under `written`:
222 `samples=<path>.wav` writes audio, encoded as `--bits` says; any other path
223 takes the reading's JSON, uncapped. A path that already holds a file refuses
224 unless `--confirm` is written. `samples=alsa:<device>` plays the samples on
225 that ALSA device (`alsa:default`, `alsa:hw:1`, `alsa:plughw:1,0`) as each
226 block is pulled, in real time, through `aplay` from alsa-utils; Linux only,
227 anywhere else it refuses as `destination.unsupported_platform`. It sends
228 32-bit floats, or integer PCM where `--bits` is 16 or under. A device that
229 cannot take the format refuses with aplay's reason, and one aplay says plays
230 another rate than the render's stops there as `destination.rate_inexact`.
231 `samples(buffer=<t>)` is how much the device holds ahead of what it plays.
232 Once it has played out, `data.played` states the device, its seconds, rate,
233 channels, format, the buffer asked and the one granted, and every underrun
234 aplay reported, with what it cannot see.
235 `lines`, `atoms`, `derivative`, `bindings`, `arguments`, and a closed form's
236 `spectrum`, `envelope` and `pitch`, read the expression and ignore the range.
237
238 A closed form's `spectrum` and `pitch` are its exact lines, so a term under a
239 crop or an envelope, which has a width and is no line, refuses them; so do
240 `spectrum(frame=)` and `envelope(frame=)`, as a closed form has no frames. To
241 measure any of them frame by frame, a reader samples the target's ref,
242 `sample(@x([0, 1s]))`, and an author writes `sample(...)` inside the node.
243 A closed form with no exact envelope, such as a crop of a decay, refuses
244 `envelope` with the reason rather than measuring it unasked; `sample(...)`
245 asks for the measured one. A knot table, `pwl(t, 0s, 0, 5ms, 1, 0.4s, 0)`,
246 is the straight lines through its knots, and `pwl_integral` with the same
247 knots that curve's integral from the first, so `cos(2*pi*pwl_integral(t, 0s,
248 440hz, 1s, 880hz))` glides an octave with an exact phase; either is exact at
249 every instant and holds any number of knots at no cost per sample, but has no
250 atoms, so these exact readings refuse it as `cast.left_algebra` and read it
251 measured off `sample(...)`. `sva-cli builtins` states both.
252 A measured `spectrum` is one spectrum: whole
253 windows across the range, averaged, the first at its first sample and the last
254 ending at its last, evenly at most half a window apart; a window is `frame`
255 rounded up to a power of two samples, at least {min_frame}, or without `frame`
256 the range's length so rounded, at most {max_frame}. `pitch` is framed, one entry
257 per `frame`; for the spectrum at one instant, read a range one frame long.
258 A measured `envelope` is framed too, and reads every channel: a frame's
259 `rms` is the root mean square of all its channels' samples together, its
260 `peak` the largest magnitude in any channel. `onsets` reads every channel
261 as well: a frame's flux is the sum of each channel's, and a strike's energy
262 that of all channels' samples together, so opposite phases cancel nothing.
263 Every other measured reading but `stereo` reads every channel in power, as
264 `envelope` reads a level: a spectrum's power per bin (`spectrum`, `pitch`,
265 the partials `dissonance`, `voice_leading`, `tonal_distance`,
266 `inharmonicity` and `self_similarity` pick), a formant frame's
267 autocorrelation and each auditory band's energy (`bands`, `periodicity`,
268 `modulation`, `self_similarity`) are each channel's averaged, so a channel
269 copied to two reads as itself; `crest` sets any channel's peak against the
270 RMS of all of them together. A closed form's exact readings read every
271 channel in power too: a partial's squared amplitude (`pitch`, `dissonance`,
272 `voice_leading`, `tonal_distance`, `inharmonicity`) is summed over the
273 channels at its frequency and divided by their count, and a spectrum of more
274 than one channel lists each frequency once, its amplitude the root of that
275 mean power, real, as channels share no phase.
276
277 `--bits <n>` is the precision every sample is written to, from 2 to 52: the
278 point where a series is truncated, and the encoding of a `.wav`, integer PCM
279 at n bits up to 16 and 32-bit float above. `--rate <hz>` (default
280 {DEFAULT_SAMPLE_RATE}) is the one rate a render samples at: the target is read
281 at its instants, and every node at the instants its reader asks for. A
282 closed form is exact at any instant, and so is a continuous loop, one
283 constant delay at a gain under 1 over a closed form such as
284 `x + 0.5*self(t - 17ms)`, which is its series. A filter, a discrete loop, a
285 solver and `rand` step at the rate asked for, where `1sp` is one step, so an
286 `sp` count or `self[idx(t) - 1]` means one sample at whatever rate is asked.
287 `rand` draws once per step, keyed by that step's index; a key between steps
288 reads the step nearest it, ties to even.
289
290 `--set <name>=<text>` renders as if the variable `variables/<name>` held
291 `<text>`, and writes no file: `--set key=G3` transposes every degree to G3,
292 `--set scale=dorian` changes mode (a scale file is a ref written from
293 `variables/`, as the file holds it: `--set scale=@../scales/custom`), `--set
294 bpm=140` moves every bar, `--set meter=3/4` regroups them and `--set
295 energy=0.8` sets a variable of the composition's own. It sets a lane's home
296 value: a move whose `to` names it follows. It may repeat, once per variable: a
297 variable set twice refuses as `render.set_twice`, a name with no file under
298 `variables/` that is no reserved one as `render.set_unreserved`, listing the
299 variables there, and the file's path, `variables/key=G3`, as
300 `render.set_path`, naming the short form.
301
302 `--threads <n>` (default: every core the machine reports) is the most
303 threads a render computes on; `1` computes every value in turn on one.
304 Values none of the others reads, and the blocks of a value that holds no
305 state, compute apart, to the same bits on any number of threads.
306
307 A discrete loop reads its own past only by index; `self(t - d)` in one
308 refuses as `type.discrete_self_at_time`, naming what made it discrete. A
309 read `@x(k*t - d)` steps `x` at `k` times the step, every input it reads,
310 `sp` and `idx` with it, and rounds `d` to the nearest sample of that step,
311 ties to even: shifts are rounded to the nearest sample so placements share
312 one cached value; timing is exact to half a sample, and the label's
313 `moved_s` states the most any read moved. A node is computed once
314 per step however many reads ask for it. A node that holds state read at a
315 time that moves refuses as `type.stateful_warp`, naming what
316 holds its state; `@x[idx(...)]` reads its nearest step instead, as `p[idx(...)]`
317 does a signal passed in as parameter `p`, and any `idx`, as
318 `idx(t - 5ms - 2ms*sin(2*pi*t))`, is read sample by sample. An edit to a
319 stream plays from the next sample on.
320
321 A render keeps in a store on disk its target and, under it, each node of
322 samples that holds state (a filter, a discrete loop or a solver in it) or
323 that two or more nodes read. Nothing else is kept. A closed form, `sample`
324 of one and `rand` have a value at any instant and are computed where read.
325 A node without state that one node alone reads, however many times, is
326 computed again by that reader from what the node itself reads: no other
327 reader could ask for it, and without state it restarts at any sample, where
328 a filter or a loop must run from its start. So a stage worth keeping is a
329 node of its own that ends in a filter or a loop, or one two nodes read. A
330 kept value is named by what it computes: never its file's name, directory,
331 comments, spacing, or the order its named arguments are written in, so a
332 renamed or moved copy, a constant lifted into a default, an expression split
333 into a file of its own or written back inline, and two addends swapped all
334 read one entry. The next render of anything that reads the same value reads
335 it back, bit for bit, and computes nothing under it. The store is on by
336 default, at `$XDG_CACHE_HOME/sva`, else `~/.cache/sva`; `--cache <path>`
337 moves it (a `/dev/shm` path keeps it in memory) and `--cache none` turns it
338 off. It holds at most {store_gb} GB, the least recently used values going
339 first, and a store another build of sva-cli wrote is emptied when opened. A
340 render stages what it computes beside the store as it goes, and the store
341 itself is written once, when the render ends, fails, or is stopped by SIGINT
342 or SIGTERM.
343
344 `ledger` prints one row per node under the target. A row's `share` is the
345 part of its reader's own energy that row accounts for, so one reader's refs
346 sum to 1; a ref no addend isolates, such as one factor of a product, and
347 every row under a silent reader, which has no energy to share out, print
348 `null`. A ref carrying a share reads as the addend it gave its reader, its
349 `rms`, `peak` and `clipped` too: in `2*@a`, `a`'s row is `a` doubled, and in
350 `@a - @a` it is silence. Each ref carrying a share is collapsed once on its
351 own, so a ledger costs one collapse per attributed ref beyond the render,
352 and `depth` bounds how many, counted in refs from one file to another. Every
353 row is computed whole over the range, however late a reader reads it.
354 `brief=1` keeps only the rows that clipped, `skim=1` drops the wider fields.
355
356 `arguments` renders nothing: for every instance under the target it prints
357 each builtin call's named arguments as the numbers the call was lowered
358 with, a solver's whole parameter set with `written: false` on each default
359 it filled in, and the operand each `min`/`max` `chosen` where a call folds
360 one to a number: in named arguments and a solver's, modal bank's or
361 `noise`'s positionals. One inside a filter's or cast's positional or
362 `rand`'s key or seed is not listed. `at` spans are bytes of the instance's
363 own body, as `sva-cli outline` counts them.
364
365REPRESENTATIONS:
366 Each one a `--representation` call, its arguments in parentheses, every
367 default under DEFAULTS. `exact` is read off the written math, `measured` off
368 samples.
369
370{representations}
371
372SOLVE:
373 sva-cli solve ('<cost>' | @fits/<name>) --vary <name>=<lo>..<hi>[/<step>][,log]...
374 [--max-renders <n>] [--step-tol <x>] [--cost-tol <x>]
375 [--set <name>=<text>]... [--rate <hz>] [--threads <n>]
376 [--cache <path|none>] [--write [--confirm]]
377
378 Fits variables under `variables/` so the targets a cost reads match a
379 reference, and prints the values it found. It edits no file unless `--write
380 --confirm` says so.
381
382 The cost is one expression typing to one number. Its leaves are
383 `repr.<reading>(<target>, <args>)`: `<reading>` spelled as `--representation`
384 spells it, `<target>` any render target with its interval as render writes
385 one, `<args>` the reading's own: `repr.pitch(@lead([0, 2s], f0=C4),
386 frame=50ms)`. Every leaf is measured off its target's samples, as `analyze`
387 reads a file, so a recording and a render are read alike. Two leaves of one
388 reading with one set of arguments subtract to a residual vector:
389{rules}
390 A level is floored at {floor} dB before it subtracts. A residual inside both
391 sides' stated bounds counts as zero; of these readings only `onsets` states
392 one. Then `norm(v)` (the root of the sum of squares), `sum(v)`, `max(v)`,
393 `abs(x)` (each value's magnitude), `dot([w1, w2, ...], v)` (one literal
394 weight per value), numbers, `+`, `-`, `*` and `/` make one number. A reading
395 left unsubtracted, a vector left unreduced and a leaf of any other reading
396 refuse before anything renders. In a node, `repr` and `load_json` are names
397 the language does not know and refuse as any such name does, with a help
398 naming `solve`.
399
400 `load_json("<file>", "<jq path>")` is a leaf read off a JSON file instead of
401 a render: plain JSON, so a `.json.gz` is unpacked first (`gunzip -k`). The
402 path is relative to the directory sva-cli runs in, or absolute, as
403 `sample("<path>")`'s is. The jq path is steps only, none of jq's filters:
404 `.name`, `[3]`, and a key that is not a plain name in single quotes,
405 `['envelope(frame=10ms)']`, so it needs no escaping in the cost's double
406 quotes: `load_json("../crop.json", ".readings['periodicity(window=5.08s)']")`.
407 A number there loads as a number and a list of numbers as a vector, both
408 usable as weights and in reducers. An object loads only as the other side of
409 a subtraction from a `repr.` leaf, and is a reading as `analyze` prints its
410 `data` (the object holding `interval` and `representations`): from a bench
411 download `.readings['<call>']`, from `analyze ref.wav --representation
412 bands=ref.json` the path `.data`. The leaf's reading reads it, and refuses
413 before the first render where its kind, its arguments, its rate, its
414 profile or its interval's length differ from what the leaf renders, or
415 where a list in it was cut short (`has_more: true`; a reading written to a
416 file is whole). Its arguments are its `args`, compared one by one with the
417 leaf's, each resolved at the solve's rate, so `frame=0.05` matches
418 `frame=50ms`; a mismatch names the argument and both values, and a reading
419 with no `representation` and `args` refuses. Each file is read once per
420 solve.
421
422 `@fits/<name>` reads the cost from the file `fits/<name>` of the
423 composition, written as a node is: an annotation line `; Models: ... |
424 Neglects: ... | IO: ... | Tags: ...`, then the cost, over as many lines as
425 it needs, every `;` comment dropped. Its quotes need no shell escaping, and
426 a cost that does not parse refuses at its line and byte in that file. No
427 node lives under `fits/`, and `lint` reads nothing there. `--vary` and the
428 other flags stay on the command line:
429 ; Models: the lead's bands against the bench crop | Neglects: pitch | IO: (cutoff) -> cost | Tags: fit
430 norm(repr.bands(@lead([0, 5.083291666666667s]))
431 - load_json("../crop.json", ".readings.bands"))
432
433 `--vary <name>=<lo>..<hi>[/<step>][,log]`, once per variable, names a file
434 `variables/<name>` holding one number and the box it moves in, both bounds in
435 one unit: none, `hz`, `khz`, `s`, `ms`, `db`, `ct` or `st`. The search starts
436 at the file's value read in that unit (`0.5` is `-6.02db` under `db` bounds).
437 `/<step>` is the first step and the grid values land on, counted from `<lo>`;
438 without it the first step is a quarter of the bounds' span. `,log` moves it on
439 a log scale, where `/<step>` is the ratio a step multiplies by, a bare number
440 above 1, as `/1.25`. A name with no file, a file holding no number in that
441 unit, and a variable no target of the cost reads each refuse before the first
442 render. `--set <name>=<text>` holds a variable at `<text>`, as render takes
443 it; a name both set and varied refuses.
444
445 The search is a deterministic compass search: from its best point it renders
446 each variable one step up and one down, in the order the `--vary`s are
447 written, and moves to the best of them that improves; where none does, every
448 step halves. A point already rendered is not rendered again. One render
449 renders every target of the cost once, through render's own path, and takes
450 every reading. A target no variable reaches, such as the reference, is read
451 back from the store on every render after its first, and `trace` shows it
452 computing no samples. A solve stops `converged` once every step is under
453 `--step-tol` of its first step or the cost is at most `--cost-tol`, `budget`
454 after `--max-renders` renders, and `cancelled` on SIGINT or SIGTERM. The
455 budget is a result, warned as `solve.budget`, not an error. Each render
456 prints one JSON line on stderr:
457 {{"render": 3, "values": {{"gain": "0.4"}}, "cost": 1.25, "best": 0.98}}
458
459 `--write` writes each fitted value to its `variables/` file, its comment line
460 kept. A file it would change refuses as `conflict` unless `--confirm` is
461 written too; that refusal still carries the fit, and `would_write`, nothing
462 written. A cancelled solve writes nothing.
463
464 Its `data`:
465 {{"cost_expression": "...", "values": {{"gain": {{"value": 0.5, "text": "0.5",
466 "unit": "", "start": "0.3", "on_bound": false}}}}, "cost": {{"total": 0.09,
467 "terms": {{"items": [{{"term": "norm(...)", "value": 0.08}}], ...}}}},
468 "renders": 49, "stopped_by": "converged", "resampled": {{"items": []}},
469 "trace": {{"items": [{{"render": 1, "values": {{"gain": {{"value": 0.3,
470 "text": "0.3"}}}}, "cost": 52.1, "computed_samples": {{"@tone": 44100,
471 "sample(\"../ref.wav\")": 44101}}}}]}}}}
472 `values` is the best point, each `text` as `--set` and a file take it; `cost`
473 its total and each top-level `+` or `-` term's signed share; `trace` every
474 render in order. A value `on_bound` sat on a bound, warned as
475 `solve.on_bound`: widen it, or the model lacks what the reference holds.
476 `--write` adds `written`, each path with its `from` and `to`. Stopped by a
477 signal, the answer is the error `cancelled`, exit 130, its `data` the best so
478 far.
479
480ANALYZE:
481 sva-cli analyze <file> --representation <list> [--confirm]
482
483 Runs the same readings over a whole recording at its own rate, never
484 resampled. It reads these formats:
485 {formats}
486 `.wav` is read exactly as written; the rest decode in sva-cli itself, an
487 MP4's encoder delay and padding trimmed as its edit list states (a bare
488 `.aac` keeps them). A lossy decode may differ slightly from a browser's
489 decoding of the same file, so its readings may differ slightly from a page's
490 readings of it. Any other format, or a file that does not decode, refuses
491 as `{unreadable}`, naming the formats it reads. Only the readings a
492 buffer answers alone apply, each listed under REPRESENTATIONS as `measured` or
493 `exact off a closed form, measured off samples`; the rest need the graph
494 behind it. Each reading states its `representation` and `args` as
495 `render`'s do, a time in seconds.
496
497LINT:
498 sva-cli lint ['<expression>'] [--format <json|text>] [--body-chars <n>]
499
500 Checks the current directory without rendering a sample. With no target it
501 checks every file under its own rules, and types every entry point, which
502 types every file it reaches. With a target, in render's grammar, it checks
503 the files that target reaches, and prints the interval a render of it reads.
504 Either refuses a type error as `render` does.
505
506 A score's annotation is its doc comment, under the same codes, and its lines
507 no body, so the length checks pass it by; a file of two or more lines that is
508 neither a score nor a scale refuses as `multiline-body` before any check
509 runs. Each song lint types prints its warnings beside the findings.
510
511 Every check prints one `data.diagnostics` item. `warning` exits 0, `error`
512 exits non-zero, so branch on the verdict and never on whether the array is
513 empty. No flag downgrades an error.
514
515 error missing-comment no `;` comment line
516 multiline-comment more than one
517 malformed-comment not four ` | ` fields, `Models:` `Neglects:`
518 `IO: <in> -> <out>` `Tags: <tag>[, <tag>...]`
519 long-comment-block a `;` block over 1000 characters, the line-1
520 doc comment's own run exempted
521 long-expression-body a body over `--body-chars` characters, a
522 backstop rather than a complexity budget; a
523 knot table's literals, its data, count none
524 literal-sample-rate a written rate where `sp` belongs
525 arity a builtin called without an argument it reads,
526 or with one it does not, as `rand(seed=k)`
527 warning key-is-not-a-pitch `variables/key` holds neither a note name nor
528 a number of hertz
529 parameter-has-no-default
530 a node reads a parameter no `name = value` line
531 binds, so a bare `@node` cannot play
532 support-never-ends a node's support, cut where its bound falls
533 under the silence threshold, has no end for a
534 bare render to stop at
535
536TRACE:
537 sva-cli trace <node|expression>
538
539 Prints one node's position without rendering audio: what it reads (`down`, one
540 hop), everything that reads it (`up`, transitively to an entry point), each
541 beside the expression doing the reading, the node that made it discrete, and
542 the feedback loop it sits in, if any. A score is shown as its line count, its
543 first and last `at` and the nodes it plays, never the sum it lowers to; every
544 entry point's song is lowered first, each at song time 0. An interval the
545 target reads is ignored.
546
547BUILTINS:
548 sva-cli builtins
549
550 Prints the whole callable and syntactic vocabulary: every builtin with its
551 arity and named arguments, each argument's `meaning`, `unit`, the model
552 `part` it sets and whether it `moves` with `t` (a filter's cutoff, q and gain;
553 every other named argument is one number, refused when it names none), each
554 positional's meaning where the model states one, unit suffixes, the note-name
555 grammar, the scales `variables/scale` may name with their cents, reserved
556 identifiers, special call shapes, and what has no operator at all.
557
558OUTLINE:
559 sva-cli outline <expression>
560
561 Prints the parse tree the engine builds from one expression, each node with
562 the byte `span` it was written in: calls by `name` with positional and named
563 `args`, operators by `op`, refs by `path` with their `binds`, refs and `self`
564 by how they `read`, `time` or `index`, literals by `value` and `unit`, names
565 by `name`. A node the parser supplies itself, the `0` of a prefix minus or the
566 `t` of a bare `@ref`, has `written: false`. Reads no composition. Score text,
567 JSON opening with `{{`, prints `score` instead of `outline`: one item per item
568 a line lists, with its `kind`, `line`, `span`, `at` with marks resolved, and
569 its `node`, `deg`, `args`, `mark` or `lane`, `to`, `len` and `shape`.
570
571 sva-cli outline @score/song
572
573 Run in a composition, outlines that score as the song a render of it is:
574 `marks` in bars and seconds, the `tempo` curve's pieces, each lane with its
575 home and every move resolved with its placement chain, how many instances it
576 reaches and how many see it move, and each placed event once, however many
577 reads reach it: its song time `at` (where it reads lanes, key and scale), when
578 it first `sounds` (later by the least, over the reads reaching it, of the
579 delays of the `t - d` reads of a score above it), its `len` in song time where
580 its line writes one, node, pitch in hertz and where each parameter comes from
581 (`line`, `lane` or `default`), and the `size`: placed events and the engine's
582 instances beside its limit.
583
584NEW:
585 sva-cli new <name> [--idempotency-key <key>]
586
587 Writes a starter composition at ./<name>, and refuses if that directory
588 exists. `--idempotency-key <key>` records the key beside the composition, so a
589 retry under the same key succeeds identically while the tree still holds what
590 was written. Any other key, or an edited tree, refuses.
591
592EXAMPLES:
593 sva-cli new song1 && cd song1
594 sva-cli render '@master' --representation samples=/tmp/song1.wav
595 sva-cli render '@master([0, 8b])' --representation 'ledger(depth=2),loudness'
596 sva-cli render '@voice/note([0, inf), f0=C4, len=2s)' \
597 --until 'envelope(t) < -60db and t > 1s' --representation samples=/tmp/note.wav
598 sva-cli render 'sample(@chord/home)' --representation 'spectrum(peaks=8)' --rate 48000
599 sva-cli render 'sample(@voice/note([0, 2s], f0=C4))' --representation pitch
600 sva-cli render '@master' --set key=G3 --set bpm=140 --set scale=dorian \
601 --representation samples=/tmp/song1-g.wav
602 sva-cli render '@master' \
603 --representation 'samples(buffer=100ms)=alsa:default,loudness'
604 sva-cli solve 'norm(repr.bands(@master([0, 4s])) - repr.bands(sample("../ref.wav")))
605 + 0.5*norm(repr.loudness(@master([0, 4s])) - repr.loudness(sample("../ref.wav")))' \
606 --vary gain=0..2/0.25 --vary cutoff=200hz..8000hz/1.25,log --rate 48000
607 sva-cli solve 'sum(abs(repr.onsets(@score/song([0, 8s]))
608 - repr.onsets(sample("/tmp/take.wav"))))' \
609 --vary bpm=100..140/2 --set key=D3 --max-renders 60 --write --confirm
610 sva-cli solve 'norm(repr.pitch(@lead([0, 2s])) - load_json("../ref.json", ".data"))' \
611 --vary detune=-50ct..50ct/10ct
612 sva-cli solve @fits/lead --vary cutoff=200hz..8000hz/1.25,log --rate 48000
613 sva-cli lint
614 sva-cli lint '@master'
615 sva-cli trace score/phrase
616 sva-cli outline @score/phrase
617 sva-cli builtins
618
619OUTPUT:
620 {{"status": "success", "data": {{"target": "@master([0, 8b])", "sample_rate":
621 {DEFAULT_SAMPLE_RATE}, "bits": {bits}, "profile": "psychoacoustic-v1",
622 "interval": {{"start_secs":
623 0, "end_secs": 16}}, "label": {{...}}, "written": {{"items": [...]}},
624 "representations": {{"ledger": {{...}}}}, "diagnostics": {{"items": []}}}},
625 "meta": {{"request_id": "req_...", "timestamp": 1700000000}}}}
626
627 `interval` is null where no reading read samples. An error adds "error":
628 {{"code", "message", "details": {{"count", "codes"}}}}. Success or error,
629 every response carries every finding in full at "data": {{"diagnostics":
630 {{"items": [{{"code", "severity", "message", "location", "help"}}],
631 "pagination": {{"count", "has_more", "next_cursor"}}}}}}, empty where it found
632 none.
633
634 Every collection carries that same {{items, pagination}} pair. `count` is the
635 whole reading's, `has_more` says `items` holds less than that, and
636 `next_cursor` is the interval start, as `0.5s`, the rest is read from. A
637 reading written to a file is written whole, uncapped. This page is an
638 envelope of its own, at "data": {{"help"}}.
639
640DEFAULTS:
641 --rate <hz> the one rate a render samples at, and `1sp`.
642 Default {DEFAULT_SAMPLE_RATE}.
643 --bits <n> the precision every sample is written to. Default {bits},
644 the `psychoacoustic-v1` profile's own.
645 ledger(depth=<n>) how deep below its target a `ledger` walks.
646 Default {DEFAULT_LEDGER_DEPTH}.
647 (peaks=<n>) peaks a `spectrum` keeps, notes a `pitch`, formants a
648 `formants`, stripes and novelty peaks a `self_similarity`
649 lists per view. Default {DEFAULT_MAX_PEAKS}; `partials`'
650 own is below.
651 alias(oversample=<n>) the multiple `alias` re-renders at to hear what folded.
652 Default {DEFAULT_OVERSAMPLE}.
653 (frame=<t>) the step a framed reading advances by, in seconds.
654 Default {DEFAULT_FRAME_SECS}, except `spectrum`, which sizes
655 its own transform to the range unless it is set, and
656 `partials`, below.
657 (floor=<db>) the amplitude, as `-40db`, under which a harmonic reading
658 or `self_similarity` drops a partial, and under which
659 `self_similarity` counts a band level as zero.
660 Default {DEFAULT_FLOOR_DB}db; `partials`' own is below.
661 voice_leading(norm=<l1|l2>) how a voice leading's moves add up. Default l1.
662 dissonance(pairs=<n>) the most partial pairs one frame sums before it refuses.
663 Default {DEFAULT_MAX_PAIRS}.
664 loudness(window=<t>) the length of one momentary block, in seconds, each a
665 quarter of one after the last, the integrated loudness
666 gated over them; both are whole samples, at least 4 in
667 a block, and the reading states them as `momentary_secs`
668 and `hop_secs`. A window under the default reads a sound
669 shorter than the default, whose integrated is null there.
670 Default {DEFAULT_LOUDNESS_WINDOW_SECS}.
671 periodicity(window=<t>) the span of onset strength one window autocorrelates,
672 in seconds, at least twice the shortest period it reads;
673 it reads periods up to half its span.
674 Default {DEFAULT_PERIODICITY_WINDOW_SECS}.
675 periodicity(curve=<0|1>) `1` adds every window's height at every lag.
676 Default 0.
677 modulation(window=<t>) the span of band envelope one window transforms, in
678 seconds, at least twice the fastest rate's period; it
679 reads rates down to two periods per span.
680 Default {DEFAULT_MODULATION_WINDOW_SECS}.
681 modulation(bpm=<n>) a tempo, as `140`, adding each rate's period in beats.
682 Default none.
683 self_similarity(cell=<t>) the side of one matrix cell, in seconds, a whole
684 number of frames holding a sample of the band
685 envelopes; the target may span at most
686 {MAX_CELLS} cells. Default {DEFAULT_CELL_SECS}.
687 self_similarity(smooth=<t>) the length each diagonal is averaged over
688 before stripes are picked, in seconds.
689 Default {DEFAULT_SMOOTH_SECS}.
690 self_similarity(window=<t>) the whole width of the novelty kernel, in
691 seconds, at most {MAX_CELLS} cells a side.
692 Default {DEFAULT_NOVELTY_WINDOW_SECS}.
693 self_similarity(curve=<0|1>) `1` adds every cell's chroma and band levels and
694 each view's matrix. Default 0.
695 partials(frame=<t>) the Hann frame `partials` finds peaks in, in seconds: two
696 partials closer than some 2 / frame Hz are one peak.
697 Default {DEFAULT_PARTIALS_FRAME_SECS}.
698 partials(window=<t>) the span of samples whose frames' power `partials`
699 averages at each hop before picking peaks, so a noise's
700 chance peaks average away; a glide crossing a frame's
701 resolution within it smears, so read one with a window
702 as short as the frame. Default {DEFAULT_PARTIALS_WINDOW_SECS}.
703 partials(hop=<t>) how often `partials` reads each track, its knots' finest
704 spacing. Default {DEFAULT_PARTIALS_HOP_SECS}.
705 partials(floor=<db>) the amplitude under which `partials` picks no peak and
706 a track reads silent. Default {DEFAULT_PARTIALS_FLOOR_DB}db.
707 partials(peaks=<n>) the most tracks `partials` keeps, those of most energy;
708 each costs its own reads of its band, in time and memory.
709 Default {DEFAULT_PARTIALS_TRACKS}.
710 bindings(node=@<path>) the instance whose bindings are read; required. An
711 instance is named exactly as the render spells it; any
712 other spelling refuses, listing its file's instances.
713 samples(buffer=<t>) how much an `alsa:` device holds ahead of what it plays,
714 in seconds. Default {DEFAULT_BUFFER_SECS}; only a device
715 has one.
716 ledger(brief, skim) `0` unless set `1`.
717 --format <json|text> how `lint` prints its findings: the envelope, or one
718 terminal line each, colored where stdout is a terminal.
719 The same objects either way. Default json.
720 --body-chars <n> the most characters a body's expression holds before
721 `long-expression-body` refuses it, a knot table's literals
722 apart. Default {body_chars}.
723 --cache <path|none> where the store lives. Default `$XDG_CACHE_HOME/sva`, else
724 `~/.cache/sva`, holding at most {store_gb} GB; `none` keeps
725 no store. A store that fails fails no render: it answers
726 as without one, warned why in `diagnostics`.
727 --set <name>=<text> a variable read as `<text>` for this render, or held for
728 a solve. Default none: each is read off its file.
729 --max-renders <n> the most renders a solve takes. Default {max_renders}.
730 --step-tol <x> the fraction of each variable's first step under which a
731 solve's search stops. Default {step_tol}.
732 --cost-tol <x> the cost at or under which a solve stops. Default {cost_tol}.
733 --write a solve writes its fitted values to their `variables/`
734 files, with `--confirm`. Default off.
735 --confirm replaces a destination that already holds a file. Without
736 it a path already taken refuses as `conflict` and nothing
737 is written.
738
739ENVIRONMENT:
740 SVA_LOG=debug `render` logs, once it ends, what it asked of each value
741 to stderr; stdout and the samples are unchanged. Any
742 other value, or none, logs nothing. One line per second
743 of output, then one per node and a total:
744 sva-cache pass hit=0 miss=190 ... reused=0 cum-hit=0.0%
745 sva-cache t=1.022s hit=1 miss=2 ... cum-hit=0.5%
746 sva-cache node hit=1 miss=0 ... reused=3 <node>
747 sva-cache total hit=1 miss=198 ... hit-rate=0.5% ...
748 `pass` is what was looked up before the first block.
749 Each value is looked up once: a `hit` was answered by
750 the store, `prefix` found a stored run up to a switch,
751 `miss` computed it, `new` held it in memory, where the
752 store takes what it keeps from. Each read of a value
753 past its first is `reused`.
754
755EXIT CODES:
756 0 success (error.code absent)
757 1 internal_error (a destination could not be written)
758 3 validation_error (bad arguments, a composition that failed to parse, or a
759 render the engine refused)
760 4 conflict (a name `new` would overwrite, a destination already holding a
761 file, or a variable file `solve --write` would change, without `--confirm`)
762 24 not_found (a `.wav` file, a `sample("<path>")` naming no file, or a node
763 this composition does not define)
764 130 cancelled (a solve stopped by SIGINT or SIGTERM, `data` the best so far)
765
766VERB ALIASES:
767 validate = lint, list = builtins, create = new, show = trace, from the `cli`
768 standard's own verb list. `render` and `analyze` take a reading, which that
769 list has no word for, so they keep their own names.
770
771SEE ALSO:
772 sva-cli --version Show version information"#
773 )
774}
775
776fn solve_rules() -> String {
778 let mut out = Vec::new();
779 for (name, rule) in solve::RULES {
780 let mut line = format!(" {name:<10}");
781 if name.len() >= 10 {
782 out.push(line);
783 line = " ".repeat(14);
784 }
785 for word in rule.split(' ') {
786 if line.len() + 1 + word.len() > 80 {
787 out.push(line);
788 line = " ".repeat(15);
789 } else {
790 line.push(' ');
791 }
792 line.push_str(word);
793 }
794 out.push(line);
795 }
796 out.join("\n")
797}
798
799fn representations() -> String {
801 READINGS
802 .iter()
803 .map(|row| {
804 let keys: Vec<&str> = row.takes.iter().map(|arg| arg.key()).collect();
805 let call = match keys[..] {
806 [] => row.name.to_string(),
807 _ => format!("{}({})", row.name, keys.join(", ")),
808 };
809 let source = match row.reads {
810 Reads::ClosedForm | Reads::Structure => "exact",
811 Reads::Either => "exact off a closed form, measured off samples",
812 Reads::Samples => "measured",
813 Reads::Graph => "measured, and the graph behind the samples",
814 };
815 format!(" {call:<26} {source}\n {}", row.help)
816 })
817 .collect::<Vec<_>>()
818 .join("\n")
819}