sending everything to the correct sample rate

Cargo.lock

@@ -1405,12 +1405,9 @@ dependencies = [
 
 [[package]]
 name = "log"
-version = "0.4.17"
+version = "0.4.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "abb12e687cfb44aa40f41fc3978ef76448f9b6038cad6aef4259d3c095a2382e"
+checksum = "b06a4cde4c0f271a446782e3eff8de789548ce57dbc8eca9292c27f4a42004b4"
-dependencies = [
- "cfg-if",
-]
 
 [[package]]
 name = "mach"
@@ -1665,6 +1662,15 @@ dependencies = [
  "minimal-lexical",
 ]
 
+[[package]]
+name = "num-complex"
+version = "0.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "02e0d21255c828d6f128a1e41534206671e8c3ea0c62f32291e808dc82cff17d"
+dependencies = [
+ "num-traits",
+]
+
 [[package]]
 name = "num-derive"
 version = "0.3.3"
@@ -1676,6 +1682,16 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "num-integer"
+version = "0.1.45"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "225d3389fb3509a24c93f5c29eb6bde2586b98d9f016636dff58d7c6f7569cd9"
+dependencies = [
+ "autocfg",
+ "num-traits",
+]
+
 [[package]]
 name = "num-traits"
 version = "0.2.15"
@@ -1914,7 +1930,9 @@ checksum = "d01a5bd0424d00070b0098dd17ebca6f961a959dead1dbcbbbc1d1cd8d3deeba"
 name = "pd-playback"
 version = "0.1.0"
 dependencies = [
+ "log",
  "minimp3",
+ "rubato",
 ]
 
 [[package]]
@@ -1980,6 +1998,15 @@ dependencies = [
  "miniz_oxide",
 ]
 
+[[package]]
+name = "primal-check"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9df7f93fd637f083201473dab4fee2db4c429d32e55e3299980ab3957ab916a0"
+dependencies = [
+ "num-integer",
+]
+
 [[package]]
 name = "proc-macro-crate"
 version = "1.2.1"
@@ -2036,6 +2063,15 @@ dependencies = [
  "cty",
 ]
 
+[[package]]
+name = "realfft"
+version = "3.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "953d9f7e5cdd80963547b456251296efc2626ed4e3cbf36c869d9564e0220571"
+dependencies = [
+ "rustfft",
+]
+
 [[package]]
 name = "redox_syscall"
 version = "0.2.16"
@@ -2130,6 +2166,18 @@ dependencies = [
  "minimp3",
 ]
 
+[[package]]
+name = "rubato"
+version = "0.14.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e6dd52e80cfc21894deadf554a5673002938ae4625f7a283e536f9cf7c17b0d5"
+dependencies = [
+ "num-complex",
+ "num-integer",
+ "num-traits",
+ "realfft",
+]
+
 [[package]]
 name = "rustc-hash"
 version = "1.1.0"
@@ -2145,6 +2193,21 @@ dependencies = [
  "semver",
 ]
 
+[[package]]
+name = "rustfft"
+version = "6.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e17d4f6cbdb180c9f4b2a26bbf01c4e647f1e1dea22fe8eb9db54198b32f9434"
+dependencies = [
+ "num-complex",
+ "num-integer",
+ "num-traits",
+ "primal-check",
+ "strength_reduce",
+ "transpose",
+ "version_check",
+]
+
 [[package]]
 name = "ryu"
 version = "1.0.12"
@@ -2468,6 +2531,12 @@ version = "1.0.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9e08d8363704e6c71fc928674353e6b7c23dcea9d82d7012c8faf2a3a025f8d0"
 
+[[package]]
+name = "strength_reduce"
+version = "0.2.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fe895eb47f22e2ddd4dabc02bce419d2e643c8e3b585c78158b349195bc24d82"
+
 [[package]]
 name = "strsim"
 version = "0.10.0"
@@ -2673,6 +2742,16 @@ dependencies = [
  "once_cell",
 ]
 
+[[package]]
+name = "transpose"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e6522d49d03727ffb138ae4cbc1283d3774f0d10aa7f9bf52e6784c45daf9b23"
+dependencies = [
+ "num-integer",
+ "strength_reduce",
+]
+
 [[package]]
 name = "try-lock"
 version = "0.2.4"

pd-playback/Cargo.toml

@@ -6,4 +6,6 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+log = "0.4.19"
 minimp3 = "0.5"
+rubato = "0.14.1"

pd-playback/src/lib.rs

@@ -1,4 +1,84 @@
-use minimp3::{Decoder, Frame}
+use std::io::Read;
+use minimp3::{ Decoder };
+use rubato::{ SincFixedIn, SincInterpolationParameters, SincInterpolationType, Resampler, WindowFunction };
+
+struct Track {
+    sample_rate: i32,
+    samples: Vec<i16>,
+}
+
+impl Track {
+    pub fn from_decoder<T: Read>(mut decoder: Decoder<T>, target_sample_rate: i32) -> Self {
+        let frames = {
+            let mut accumulator = vec![];
+            while let Ok(frame) = decoder.next_frame() {
+                accumulator.push(frame);
+            }
+            accumulator
+        };
+
+        let mut output_buffer = Vec::with_capacity(frames.len() * minimp3::MAX_SAMPLES_PER_FRAME);
+        let mut resampler = SincFixedIn::new(
+            target_sample_rate as f64 / frames[0].sample_rate as f64,
+            10.0,
+            SincInterpolationParameters {
+                sinc_len: 256,
+                f_cutoff: 0.95,
+                oversampling_factor: 128,
+                interpolation: SincInterpolationType::Linear,
+                window: WindowFunction::BlackmanHarris2,
+            },
+            1152,
+            2
+        ).unwrap();
+
+        for frame in frames.iter() {
+            let mut deinterlaced_left = [0f32; 1152];
+            let mut deinterlaced_right = [0f32; 1152];
+            match frame.channels {
+                1 => {
+                    frame.data.iter()
+                              .map(|&sample| sample as f32)
+                              .enumerate()
+                              .for_each(|(i, sample)| deinterlaced_left[i] = sample);
+                    deinterlaced_right.copy_from_slice(&deinterlaced_left);
+                },
+
+                2 => {
+                    // if not fast enough, try the unsafe as_mut_ptr shit
+                    // edit: unsafe stuff probably wont help actually bc iteration would have to
+                    // happen anyway and also we still have to convert i32 to f32
+                    let (d_left_vec, d_right_vec): (Vec<f32>, Vec<f32>) 
+                        = frame.data.as_slice()
+                                    .chunks(2)
+                                    .map(|c| (c[0] as f32, c[1] as f32))
+                                    .unzip();
+
+                    deinterlaced_left[0..d_left_vec.len()]
+                                        .copy_from_slice(&d_left_vec);
+                    deinterlaced_right[0..d_right_vec.len()]
+                                        .copy_from_slice(&d_right_vec);
+                },
+
+                _ => panic!("frame {} had {} channels, should only have 1 or 2", frames.len(), frame.channels)
+            }
+
+            let mut frame_resampled = resampler
+                .process(&[deinterlaced_left, deinterlaced_right], None)
+                .unwrap();
+            let frame_resampled_right = frame_resampled.pop().unwrap();
+            let frame_resampled_left = frame_resampled.pop().unwrap();
+
+            let frame_resampled_interlaced = frame_resampled_left
+                .into_iter()
+                .zip(frame_resampled_right.into_iter())
+                .flat_map(|(l, r)| [l, r]);
+
+            output_buffer.extend(frame_resampled_interlaced);
+        }
+        todo!()
+    }
+}
 
 #[cfg(test)]
 mod tests {