Add a "disable-ffmpeg" feature

Cargo.toml

@@ -28,6 +28,9 @@ update-aubio-bindings = ["bliss-audio-aubio-rs/bindgen"]
 python-bindings = ["bliss-audio-aubio-rs/fftw3"]
 # Enable the benchmarks with `cargo +nightly bench --features=bench`
 bench = []
+# Disable song decoding through ffmpeg - only use if you know what you
+# are doing and want to decode songs yourself
+disable-ffmpeg = []
 library = [
     "serde", "dep:rusqlite", "dep:dirs", "dep:tempdir",
     "dep:anyhow", "dep:serde_ini", "dep:serde_json",
@@ -84,4 +87,12 @@ required-features = ["library"]
 
 [[example]]
 name = "playlist"
-required-features = ["serde"]
+required-features = ["serde", "ffmpeg"]
+
+[[example]]
+name = "distance"
+required-features = ["ffmpeg"]
+
+[[example]]
+name = "analyze"
+required-features = ["ffmpeg"]

src/chroma.rs

@@ -434,6 +434,7 @@ mod test {
     }
 
     #[test]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn test_chroma_desc() {
         let song = Song::decode(Path::new("data/s16_mono_22_5kHz.flac")).unwrap();
         let mut chroma_desc = ChromaDesc::new(SAMPLE_RATE, 12);
@@ -456,6 +457,7 @@ mod test {
     }
 
     #[test]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn test_chroma_stft_decode() {
         let signal = Song::decode(Path::new("data/s16_mono_22_5kHz.flac"))
             .unwrap()
@@ -489,6 +491,7 @@ mod test {
     }
 
     #[test]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn test_estimate_tuning_decode() {
         let signal = Song::decode(Path::new("data/s16_mono_22_5kHz.flac"))
             .unwrap()
@@ -606,6 +609,7 @@ mod bench {
     }
 
     #[bench]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn bench_chroma_desc(b: &mut Bencher) {
         let song = Song::decode(Path::new("data/s16_mono_22_5kHz.flac")).unwrap();
         let mut chroma_desc = ChromaDesc::new(SAMPLE_RATE, 12);
@@ -617,6 +621,7 @@ mod bench {
     }
 
     #[bench]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn bench_chroma_stft(b: &mut Bencher) {
         let song = Song::decode(Path::new("data/s16_mono_22_5kHz.flac")).unwrap();
         let mut chroma_desc = ChromaDesc::new(SAMPLE_RATE, 12);
@@ -628,6 +633,7 @@ mod bench {
     }
 
     #[bench]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn bench_chroma_stft_decode(b: &mut Bencher) {
         let signal = Song::decode(Path::new("data/s16_mono_22_5kHz.flac"))
             .unwrap()

src/cue.rs

@@ -49,6 +49,7 @@ impl BlissCue {
     /// Each returned [Song] has a populated [cue_info](Song::cue_info) object, that can be
     /// be used to retrieve which CUE sheet was used to extract it, as well
     /// as the corresponding audio file.
+    #[cfg(not(feature = "disable-ffmpeg"))]
     pub fn songs_from_path<P: AsRef<Path>>(path: P) -> BlissResult<Vec<BlissResult<Song>>> {
         let cue = BlissCue::from_path(&path)?;
         let cue_files = cue.files();
@@ -86,6 +87,7 @@ impl BlissCue {
     }
 
     // List all BlissCueFile from a BlissCue.
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn files(&self) -> Vec<BlissResult<BlissCueFile>> {
         let mut cue_files = Vec::new();
         for cue_file in self.cue.files.iter() {
@@ -196,6 +198,7 @@ mod tests {
     use pretty_assertions::assert_eq;
 
     #[test]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn test_empty_cue() {
         let songs = BlissCue::songs_from_path("data/empty.cue").unwrap();
         let error = songs[0].to_owned().unwrap_err();
@@ -206,6 +209,7 @@ mod tests {
     }
 
     #[test]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn test_cue_analysis() {
         let songs = BlissCue::songs_from_path("data/testcue.cue").unwrap();
         let expected = vec![

src/lib.rs

@@ -23,9 +23,13 @@
 //! an example of how the [Library] struct works, and a real-life demo of bliss
 //! implemented for [MPD](https://www.musicpd.org/).
 //!
+#![cfg_attr(
+    not(feature = "disable-ffmpeg"),
+    doc = r##"
 //! # Examples
 //!
 //! ### Analyze & compute the distance between two songs
+//!
 //! ```no_run
 //! use bliss_audio::{BlissResult, Song};
 //!
@@ -62,6 +66,8 @@
 //!     Ok(())
 //! }
 //! ```
+"##
+)]
 #![cfg_attr(feature = "bench", feature(test))]
 #![warn(missing_docs)]
 mod chroma;
@@ -152,6 +158,7 @@ pub type BlissResult<T> = Result<T, BlissError>;
 ///     Ok(())
 /// }
 /// ```
+#[cfg(not(feature = "disable-ffmpeg"))]
 pub fn analyze_paths<P: Into<PathBuf>, F: IntoIterator<Item = P>>(
     paths: F,
 ) -> mpsc::IntoIter<(PathBuf, BlissResult<Song>)> {
@@ -199,6 +206,7 @@ pub fn analyze_paths<P: Into<PathBuf>, F: IntoIterator<Item = P>>(
 ///     Ok(())
 /// }
 /// ```
+#[cfg(not(feature = "disable-ffmpeg"))]
 pub fn analyze_paths_with_cores<P: Into<PathBuf>, F: IntoIterator<Item = P>>(
     paths: F,
     number_cores: NonZeroUsize,
@@ -270,6 +278,7 @@ mod tests {
     }
 
     #[test]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn test_analyze_paths() {
         let paths = vec![
             "./data/s16_mono_22_5kHz.flac",

src/misc.rs

@@ -67,6 +67,7 @@ mod tests {
     use std::path::Path;
 
     #[test]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn test_loudness() {
         let song = Song::decode(Path::new("data/s16_mono_22_5kHz.flac")).unwrap();
         let mut loudness_desc = LoudnessDesc::default();

src/song.rs

@@ -8,6 +8,7 @@
 //! a look at Library is instead recommended.
 
 extern crate crossbeam;
+#[cfg(not(feature = "disable-ffmpeg"))]
 extern crate ffmpeg_next as ffmpeg;
 extern crate ndarray;
 
@@ -24,13 +25,21 @@ use crate::{CHANNELS, FEATURES_VERSION};
 use ::log::warn;
 use core::ops::Index;
 use crossbeam::thread;
+#[cfg(not(feature = "disable-ffmpeg"))]
 use ffmpeg_next::codec::threading::{Config, Type as ThreadingType};
+#[cfg(not(feature = "disable-ffmpeg"))]
 use ffmpeg_next::util::channel_layout::ChannelLayout;
+#[cfg(not(feature = "disable-ffmpeg"))]
 use ffmpeg_next::util::error::Error;
+#[cfg(not(feature = "disable-ffmpeg"))]
 use ffmpeg_next::util::error::EINVAL;
+#[cfg(not(feature = "disable-ffmpeg"))]
 use ffmpeg_next::util::format::sample::{Sample, Type};
+#[cfg(not(feature = "disable-ffmpeg"))]
 use ffmpeg_next::util::frame::audio::Audio;
+#[cfg(not(feature = "disable-ffmpeg"))]
 use ffmpeg_next::util::log;
+#[cfg(not(feature = "disable-ffmpeg"))]
 use ffmpeg_next::util::log::level::Level;
 use ffmpeg_next::{media, util};
 use ndarray::{arr1, Array1};
@@ -84,6 +93,9 @@ pub struct Song {
 #[derive(Debug, EnumIter, EnumCount)]
 /// Indexes different fields of an [Analysis](Song::analysis).
 ///
+#[cfg_attr(
+    not(feature = "disable-ffmpeg"),
+    doc = r##"
 /// * Example:
 /// ```no_run
 /// use bliss_audio::{AnalysisIndex, BlissResult, Song};
@@ -94,7 +106,8 @@ pub struct Song {
 ///     Ok(())
 /// }
 /// ```
-///
+"##
+)]
 /// Prints the tempo value of an analysis.
 ///
 /// Note that this should mostly be used for debugging / distance metric
@@ -296,6 +309,7 @@ impl Song {
     /// The error type returned should give a hint as to whether it was a
     /// decoding ([DecodingError](BlissError::DecodingError)) or an analysis
     /// ([AnalysisError](BlissError::AnalysisError)) error.
+    #[cfg(not(feature = "disable-ffmpeg"))]
     pub fn from_path<P: AsRef<Path>>(path: P) -> BlissResult<Self> {
         let raw_song = Song::decode(path.as_ref())?;
 
@@ -437,6 +451,7 @@ impl Song {
         .unwrap()
     }
 
+    #[cfg(not(feature = "disable-ffmpeg"))]
     pub(crate) fn decode(path: &Path) -> BlissResult<InternalSong> {
         ffmpeg::init().map_err(|e| {
             BlissError::DecodingError(format!(
@@ -658,6 +673,7 @@ pub(crate) struct InternalSong {
     pub sample_array: Vec<f32>,
 }
 
+#[cfg(not(feature = "disable-ffmpeg"))]
 fn resample_frame(
     rx: Receiver<Audio>,
     in_codec_format: Sample,
@@ -727,6 +743,7 @@ fn resample_frame(
     Ok(sample_array)
 }
 
+#[cfg(not(feature = "disable-ffmpeg"))]
 fn push_to_sample_array(frame: &ffmpeg::frame::Audio, sample_array: &mut Vec<f32>) {
     if frame.samples() == 0 {
         return;
@@ -772,6 +789,7 @@ mod tests {
     }
 
     #[test]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn test_analyze() {
         let song = Song::from_path(Path::new("data/s16_mono_22_5kHz.flac")).unwrap();
         let expected_analysis = vec![
@@ -802,6 +820,7 @@ mod tests {
         assert_eq!(FEATURES_VERSION, song.features_version);
     }
 
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn _test_decode(path: &Path, expected_hash: &[u8]) {
         let song = Song::decode(path).unwrap();
         let mut hasher = Ripemd160::new();
@@ -813,6 +832,7 @@ mod tests {
     }
 
     #[test]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn test_tags() {
         let song = Song::decode(Path::new("data/s16_mono_22_5kHz.flac")).unwrap();
         assert_eq!(song.artist, Some(String::from("David TMX")));
@@ -830,6 +850,7 @@ mod tests {
     }
 
     #[test]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn test_empty_tags() {
         let song = Song::decode(Path::new("data/no_tags.flac")).unwrap();
         assert_eq!(song.artist, None);
@@ -840,6 +861,7 @@ mod tests {
     }
 
     #[test]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn test_resample_multi() {
         let path = Path::new("data/s32_stereo_44_1_kHz.flac");
         let expected_hash = [
@@ -850,6 +872,7 @@ mod tests {
     }
 
     #[test]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn test_resample_stereo() {
         let path = Path::new("data/s16_stereo_22_5kHz.flac");
         let expected_hash = [
@@ -860,6 +883,7 @@ mod tests {
     }
 
     #[test]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn test_decode_mono() {
         let path = Path::new("data/s16_mono_22_5kHz.flac");
         // Obtained through
@@ -873,6 +897,7 @@ mod tests {
     }
 
     #[test]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn test_decode_mp3() {
         let path = Path::new("data/s32_stereo_44_1_kHz.mp3");
         // Obtained through
@@ -886,12 +911,14 @@ mod tests {
     }
 
     #[test]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn test_dont_panic_no_channel_layout() {
         let path = Path::new("data/no_channel.wav");
         Song::decode(&path).unwrap();
     }
 
     #[test]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn test_decode_right_capacity_vec() {
         let path = Path::new("data/s16_mono_22_5kHz.flac");
         let song = Song::decode(&path).unwrap();
@@ -945,6 +972,7 @@ mod tests {
     }
 
     #[test]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn test_decode_errors() {
         assert_eq!(
             Song::decode(Path::new("nonexistent")).unwrap_err(),
@@ -961,13 +989,15 @@ mod tests {
     }
 
     #[test]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn test_index_analysis() {
         let song = Song::from_path("data/s16_mono_22_5kHz.flac").unwrap();
         assert_eq!(song.analysis[AnalysisIndex::Tempo], 0.3846389);
         assert_eq!(song.analysis[AnalysisIndex::Chroma10], -0.95968974);
     }
 
     #[test]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn test_decode_wav() {
         let expected_hash = [
             0xf0, 0xe0, 0x85, 0x4e, 0xf6, 0x53, 0x76, 0xfa, 0x7a, 0xa5, 0x65, 0x76, 0xf9, 0xe1,
@@ -977,6 +1007,7 @@ mod tests {
     }
 
     #[test]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn test_debug_analysis() {
         let song = Song::from_path("data/s16_mono_22_5kHz.flac").unwrap();
         assert_eq!(
@@ -1097,7 +1128,7 @@ mod tests {
     }
 }
 
-#[cfg(all(feature = "bench", test))]
+#[cfg(all(feature = "bench", not(feature = "disable-ffmpeg"), test))]
 mod bench {
     extern crate test;
     use crate::Song;

src/temporal.rs

@@ -98,6 +98,7 @@ mod tests {
     use std::path::Path;
 
     #[test]
+    #[cfg(not(feature = "disable-ffmpeg"))]
     fn test_tempo_real() {
         let song = Song::decode(Path::new("data/s16_mono_22_5kHz.flac")).unwrap();
         let mut tempo_desc = BPMDesc::new(SAMPLE_RATE).unwrap();