diff --git a/CHANGELOG.md b/CHANGELOG.md
index 81de34d..749d19d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changelog
 
+## bliss 0.2.2
+
+* Made `NUMBER_FEATURES` public.
+
 ## bliss 0.2.1
 
 * Made `Analysis::new` public.
diff --git a/Cargo.lock b/Cargo.lock
index 4522bae..fdaf92f 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -75,7 +75,7 @@ checksum = "cf1de2fe8c75bc145a2f577add951f8134889b4795d47466a54a5c846d691693"
 
 [[package]]
 name = "bliss-audio"
-version = "0.2.0"
+version = "0.2.1"
 dependencies = [
  "bliss-audio-aubio-rs",
  "crossbeam",
@@ -160,9 +160,9 @@ checksum = "14c189c53d098945499cdfa7ecc63567cf3886b3332b312a5b4585d8d3a6a610"
 
 [[package]]
 name = "bzip2"
-version = "0.3.3"
+version = "0.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "42b7c3cbf0fa9c1b82308d57191728ca0256cb821220f4e2fd410a72ade26e3b"
+checksum = "abf8012c8a15d5df745fcf258d93e6149dcf102882c8d8702d9cff778eab43a8"
 dependencies = [
  "bzip2-sys",
  "libc",
@@ -181,9 +181,9 @@ dependencies = [
 
 [[package]]
 name = "cc"
-version = "1.0.67"
+version = "1.0.68"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e3c69b077ad434294d3ce9f1f6143a2a4b89a8a2d54ef813d85003a4fd1137fd"
+checksum = "4a72c244c1ff497a746a7e1fb3d14bd08420ecda70c8f25c7112f2781652d787"
 dependencies = [
  "jobserver",
 ]
@@ -241,9 +241,9 @@ dependencies = [
 
 [[package]]
 name = "crossbeam"
-version = "0.8.0"
+version = "0.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fd01a6eb3daaafa260f6fc94c3a6c36390abc2080e38e3e34ced87393fb77d80"
+checksum = "4ae5588f6b3c3cb05239e90bd110f257254aecd01e4635400391aeae07497845"
 dependencies = [
  "cfg-if 1.0.0",
  "crossbeam-channel",
@@ -276,9 +276,9 @@ dependencies = [
 
 [[package]]
 name = "crossbeam-epoch"
-version = "0.9.4"
+version = "0.9.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "52fb27eab85b17fbb9f6fd667089e07d6a2eb8743d02639ee7f6a7a7729c9c94"
+checksum = "4ec02e091aa634e2c3ada4a392989e7c3116673ef0ac5b72232439094d73b7fd"
 dependencies = [
  "cfg-if 1.0.0",
  "crossbeam-utils",
@@ -289,9 +289,9 @@ dependencies = [
 
 [[package]]
 name = "crossbeam-queue"
-version = "0.3.1"
+version = "0.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0f6cb3c7f5b8e51bc3ebb73a2327ad4abdbd119dc13223f14f961d2f38486756"
+checksum = "9b10ddc024425c88c2ad148c1b0fd53f4c6d38db9697c9f1588381212fa657c9"
 dependencies = [
  "cfg-if 1.0.0",
  "crossbeam-utils",
@@ -299,11 +299,10 @@ dependencies = [
 
 [[package]]
 name = "crossbeam-utils"
-version = "0.8.4"
+version = "0.8.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4feb231f0d4d6af81aed15928e58ecf5816aa62a2393e2c82f46973e92a9a278"
+checksum = "d82cfc11ce7f2c3faef78d8a684447b40d503d9681acebed6cb728d45940c4db"
 dependencies = [
- "autocfg",
  "cfg-if 1.0.0",
  "lazy_static 1.4.0",
 ]
@@ -450,9 +449,9 @@ dependencies = [
 
 [[package]]
 name = "getrandom"
-version = "0.2.2"
+version = "0.2.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c9495705279e7140bf035dde1f6e750c162df8b625267cd52cc44e0b156732c8"
+checksum = "7fcd999463524c52659517fe2cea98493cfe485d10565e7b0fb07dbba7ad2753"
 dependencies = [
  "cfg-if 1.0.0",
  "libc",
@@ -473,9 +472,9 @@ checksum = "d7afe4a420e3fe79967a00898cc1f4db7c8a49a9333a29f8a4bd76a253d5cd04"
 
 [[package]]
 name = "heck"
-version = "0.3.2"
+version = "0.3.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "87cbf45460356b7deeb5e3415b5563308c0a9b057c85e12b06ad551f98d0a6ac"
+checksum = "6d621efb26863f0e9924c6ac577e8275e5e6b77455db64ffa6c65c904e9e132c"
 dependencies = [
  "unicode-segmentation",
 ]
@@ -553,9 +552,9 @@ checksum = "830d08ce1d1d941e6b30645f1a0eb5643013d835ce3779a5fc208261dbe10f55"
 
 [[package]]
 name = "libc"
-version = "0.2.94"
+version = "0.2.95"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "18794a8ad5b29321f790b55d93dfba91e125cb1a9edbd4f8e3150acc771c1a5e"
+checksum = "789da6d93f1b866ffe175afc5322a4d76c038605a1c3319bb57b06967ca98a36"
 
 [[package]]
 name = "libloading"
@@ -608,9 +607,9 @@ checksum = "b16bd47d9e329435e309c58469fe0791c2d0d1ba96ec0954152a5ae2b04387dc"
 
 [[package]]
 name = "memoffset"
-version = "0.6.3"
+version = "0.6.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f83fb6581e8ed1f85fd45c116db8405483899489e38406156c25eb743554361d"
+checksum = "59accc507f1338036a0477ef61afdae33cde60840f4dfe481319ce3ad116ddf9"
 dependencies = [
  "autocfg",
 ]
@@ -627,9 +626,9 @@ dependencies = [
 
 [[package]]
 name = "ndarray"
-version = "0.15.1"
+version = "0.15.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cc1372704f14bb132a49a6701c2238970a359ee0829fed481b522a63bf25456a"
+checksum = "08e854964160a323e65baa19a0b1a027f76d590faba01f05c0cbc3187221a8c9"
 dependencies = [
  "matrixmultiply",
  "num-complex 0.4.0",
@@ -850,9 +849,9 @@ dependencies = [
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.26"
+version = "1.0.27"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a152013215dca273577e18d2bf00fa862b89b24169fb78c4c95aeb07992c9cec"
+checksum = "f0d8caf72986c1a598726adc988bb5984792ef84f5ee5aa50209145ee8077038"
 dependencies = [
  "unicode-xid",
 ]
@@ -927,9 +926,9 @@ checksum = "60a357793950651c4ed0f3f52338f53b2f809f32d83a07f72909fa13e4c6c1e3"
 
 [[package]]
 name = "rayon"
-version = "1.5.0"
+version = "1.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8b0d8e0819fadc20c74ea8373106ead0600e3a67ef1fe8da56e39b9ae7275674"
+checksum = "c06aca804d41dbc8ba42dfd964f0d01334eceb64314b9ecf7c5fad5188a06d90"
 dependencies = [
  "autocfg",
  "crossbeam-deque",
@@ -939,9 +938,9 @@ dependencies = [
 
 [[package]]
 name = "rayon-core"
-version = "1.9.0"
+version = "1.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9ab346ac5921dc62ffa9f89b7a773907511cdfa5490c572ae9be1be33e8afa4a"
+checksum = "d78120e2c850279833f1dd3582f730c4ab53ed95aeaaaa862a2a5c71b1656d8e"
 dependencies = [
  "crossbeam-channel",
  "crossbeam-deque",
@@ -1075,9 +1074,9 @@ checksum = "aaf86bbcfd1fa9670b7a129f64fc0c9fcbbfe4f1bc4210e9e98fe71ffc12cde2"
 
 [[package]]
 name = "strum_macros"
-version = "0.21.0"
+version = "0.21.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cb076d8b589fde927ec90d05920d610554ca3a4d9dddb177481cadd071a19c2e"
+checksum = "d06aaeeee809dbc59eb4556183dd927df67db1540de5be8d3ec0b6636358a5ec"
 dependencies = [
  "heck",
  "proc-macro2",
@@ -1107,18 +1106,18 @@ dependencies = [
 
 [[package]]
 name = "thiserror"
-version = "1.0.24"
+version = "1.0.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e0f4a65597094d4483ddaed134f409b2cb7c1beccf25201a9f73c719254fa98e"
+checksum = "fa6f76457f59514c7eeb4e59d891395fab0b2fd1d40723ae737d64153392e9c6"
 dependencies = [
  "thiserror-impl",
 ]
 
 [[package]]
 name = "thiserror-impl"
-version = "1.0.24"
+version = "1.0.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7765189610d8241a44529806d6fd1f2e0a08734313a35d5b3a556f92b381f3c0"
+checksum = "8a36768c0fbf1bb15eca10defa29526bda730a2376c2ab4393ccfa16fb1a318d"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -1196,9 +1195,9 @@ checksum = "a1ca13c08c41c9c3e04224ed9ff80461d97e121589ff27c753a16cb10830ae0f"
 
 [[package]]
 name = "vcpkg"
-version = "0.2.12"
+version = "0.2.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cbdbff6266a24120518560b5dc983096efb98462e51d0d68169895b237be3e5d"
+checksum = "025ce40a007e1907e58d5bc1a594def78e5573bb0b1160bc389634e8f12e4faa"
 
 [[package]]
 name = "version_check"
@@ -1257,9 +1256,9 @@ checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
 
 [[package]]
 name = "zip"
-version = "0.5.12"
+version = "0.5.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9c83dc9b784d252127720168abd71ea82bf8c3d96b17dc565b5e2a02854f2b27"
+checksum = "93ab48844d61251bb3835145c521d88aa4031d7139e8485990f60ca911fa0815"
 dependencies = [
  "byteorder",
  "bzip2",
diff --git a/src/song.rs b/src/song.rs
index d537562..3098a77 100644
--- a/src/song.rs
+++ b/src/song.rs
@@ -102,7 +102,8 @@ pub enum AnalysisIndex {
     Chroma9,
     Chroma10,
 }
-const NUMBER_FEATURES: usize = AnalysisIndex::COUNT;
+/// The number of features used in `Analysis`
+pub const NUMBER_FEATURES: usize = AnalysisIndex::COUNT;
 
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 #[derive(Default, PartialEq, Clone, Copy)]