Crate brk_oracle 

Pure on-chain BTC/USD price oracle.

Detects round-dollar transaction patterns ($1, $5, $10, … $10,000) in Bitcoin block outputs to derive the current price without any exchange data.

Behavior changes by height along two independent axes, each in its own module:

• EMA regime (config): below START_HEIGHT_SLOW prices come from the baked pre-oracle tape. From there to START_HEIGHT_FAST a slow cold-start EMA runs with a shape-anchoring restoring force. At START_HEIGHT_FAST it switches to a fast EMA that tracks mature-market volatility.
• Output filter (filter): below PaymentFilter::MODERN_TX_OUTPUT_FANOUT_CAP_START_HEIGHT batch-payout transactions are capped strictly. Above it the cap relaxes but still drops very large fan-outs.

The two boundaries differ on purpose. The EMA must hand off to fast before the 2020 crash, while the output cap helps the thin pre-2020 mix for longer and still prevents modern fan-out clusters from dominating one EMA slot.

Structs

Config

HistogramEma

HistogramEmaCompact

HistogramRaw

Oracle

PaymentFilter

Round-dollar payment filter.

Constants

BINS_PER_DECADE

NUM_BINS

START_HEIGHT_FAST

Height where the oracle switches slow -> fast EMA (default). The regimes are complementary: slow resists the round-USD half-price drift that locks fast below here, while fast tracks the 2018-2019 crashes that lock slow.

START_HEIGHT_SLOW

First height the oracle computes on-chain, with the slow cold-start EMA (slow). Below it, prices come from pre_oracle_prices_from.

VERSION

Oracle algorithm version. Bump on any change that alters computed prices so downstream consumers can invalidate cached results.

Functions

bin_to_cents

Converts a fractional bin to a USD price in cents. For a $D output at price P: sats = D * 1e8 / P, so P = 10^(10 - bin/200) dollars, where 10 = log10($100 reference * 1e8 sats/BTC).

cents_to_bin

Converts a USD price in cents to a fractional bin (inverse of bin_to_cents).

pre_oracle_price_cents

Baked pre-oracle price at height, or None once on-chain oracle prices start.

pre_oracle_prices_from

Baked pre-oracle prices starting at start_height, as a one-pass iterator.

sats_to_bin

Maps a satoshi value to its log-scale bin index. bin = round(log10(sats) * BINS_PER_DECADE).

seed_bin

Initial reference bin for processing height START_HEIGHT_SLOW.

seed_price_cents

Baked exchange price for the block immediately before on-chain oracle prices start.