refactor: add DEFAULT_SAMPLE_RATE and default to 48 kHz

CHANGELOG.md

@@ -15,6 +15,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - All sources now implement `ExactSizeIterator` when their inner source does.
 - All sources now implement `Iterator::size_hint()`.
 - `Chirp` now implements `try_seek`.
+- Added `DEFAULT_SAMPLE_RATE` set to match `cpal::SAMPLE_RATE_48K`.
 
 ### Changed
 
@@ -25,6 +26,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Ensured decoders to always return complete frames, as well as `TakeDuration` when expired.
 - Breaking: `Zero::new_samples()` now returns `Result<Self, ZeroError>` requiring a frame-aligned number of samples.
 - Improved queue, buffer, mixer and sample rate conversion performance.
+- Default sample rate changed from 44.1 kHz to 48 kHz consistently.
+- `open_sink_or_fallback` now tries 48 kHz and 44.1 kHz before the device's maximum sample rate.
+
+### Removed
+
+- Breaking: Removed `stream::supported_output_configs`. Use `cpal::Device::supported_output_configs`.
 
 ### Fixed
 

UPGRADE.md

@@ -6,6 +6,9 @@ The list below only contains required code changes. For a complete list of
 changes and new features, see [CHANGELOG.md](CHANGELOG.md).
 
 # rodio 0.22 to current github version
+- `stream::supported_output_configs` is removed. To pick a non-default device config,
+  call `device.supported_output_configs()` directly and pass your chosen
+  `SupportedStreamConfig` to `DeviceSinkBuilder::with_supported_config`.
 - `Done` now calls a callback instead of decrementing an `Arc<AtomicUsize>`.
   - To retain old behavior replace the `Arc<AtomicUsize>` argument in `Done::new` with
     `move |_| { number.fetch_sub(1, std::sync::atomic::Ordering::Relaxed) }`.

src/common.rs

@@ -1,9 +1,14 @@
 use std::fmt::{Debug, Display};
 use std::num::NonZero;
 
+use crate::math::nz;
+
 /// Sample rate (a frame rate or samples per second per channel).
 pub type SampleRate = NonZero<u32>;
 
+/// The default sample rate used by rodio for generators and device sinks.
+pub const DEFAULT_SAMPLE_RATE: SampleRate = nz!(48_000);
+
 /// Number of channels in a stream. Can never be Zero
 pub type ChannelCount = NonZero<u16>;
 

src/decoder/mod.rs

@@ -734,7 +734,7 @@ where
     fn sample_rate(&self) -> SampleRate {
         self.inner
             .as_ref()
-            .map_or(nz!(44100), |inner| inner.sample_rate())
+            .map_or(crate::DEFAULT_SAMPLE_RATE, |inner| inner.sample_rate())
     }
 
     /// Returns the total duration of this audio source.

src/lib.rs

@@ -215,7 +215,7 @@ pub mod queue;
 pub mod source;
 pub mod static_buffer;
 
-pub use crate::common::{BitDepth, ChannelCount, Float, Sample, SampleRate};
+pub use crate::common::{BitDepth, ChannelCount, Float, Sample, SampleRate, DEFAULT_SAMPLE_RATE};
 pub use crate::decoder::Decoder;
 #[cfg(feature = "experimental")]
 pub use crate::fixed_source::FixedSource;

src/microphone/config.rs

@@ -74,7 +74,7 @@ impl Default for InputConfig {
     fn default() -> Self {
         Self {
             channel_count: nz!(1),
-            sample_rate: nz!(44_100),
+            sample_rate: crate::DEFAULT_SAMPLE_RATE,
             buffer_size: cpal::BufferSize::Default,
             sample_format: cpal::SampleFormat::F32,
         }

src/queue.rs

@@ -419,8 +419,8 @@ mod tests {
             );
             assert_eq!(
                 rx.sample_rate(),
-                nz!(48000),
-                "Initial sample rate should be 48000 (keep_alive={keep_alive})"
+                crate::DEFAULT_SAMPLE_RATE,
+                "Initial sample rate should be DEFAULT_SAMPLE_RATE (keep_alive={keep_alive})"
             );
 
             tx.append(SamplesBuffer::new(

src/source/empty.rs

@@ -47,7 +47,7 @@ impl Source for Empty {
 
     #[inline]
     fn sample_rate(&self) -> SampleRate {
-        nz!(48000)
+        crate::DEFAULT_SAMPLE_RATE
     }
 
     #[inline]

src/source/empty_callback.rs

@@ -51,7 +51,7 @@ impl Source for EmptyCallback {
 
     #[inline]
     fn sample_rate(&self) -> SampleRate {
-        nz!(48000)
+        crate::DEFAULT_SAMPLE_RATE
     }
 
     #[inline]

src/source/from_iter.rs

@@ -103,7 +103,7 @@ where
             src.sample_rate()
         } else {
             // Dummy value that only happens if the iterator was empty.
-            nz!(44100)
+            crate::DEFAULT_SAMPLE_RATE
         }
     }
 

src/source/sawtooth.rs

@@ -18,13 +18,11 @@ pub struct SawtoothWave {
 }
 
 impl SawtoothWave {
-    const SAMPLE_RATE: SampleRate = nz!(48000);
-
     /// The frequency of the sine.
     #[inline]
     pub fn new(freq: f32) -> SawtoothWave {
         SawtoothWave {
-            test_saw: SignalGenerator::new(Self::SAMPLE_RATE, freq, Function::Sawtooth),
+            test_saw: SignalGenerator::new(crate::DEFAULT_SAMPLE_RATE, freq, Function::Sawtooth),
         }
     }
 }
@@ -56,7 +54,7 @@ impl Source for SawtoothWave {
 
     #[inline]
     fn sample_rate(&self) -> SampleRate {
-        Self::SAMPLE_RATE
+        crate::DEFAULT_SAMPLE_RATE
     }
 
     #[inline]

src/source/sine.rs

@@ -18,13 +18,11 @@ pub struct SineWave {
 }
 
 impl SineWave {
-    const SAMPLE_RATE: SampleRate = nz!(48000);
-
     /// The frequency of the sine.
     #[inline]
     pub fn new(freq: f32) -> SineWave {
         SineWave {
-            test_sine: SignalGenerator::new(Self::SAMPLE_RATE, freq, Function::Sine),
+            test_sine: SignalGenerator::new(crate::DEFAULT_SAMPLE_RATE, freq, Function::Sine),
         }
     }
 }
@@ -56,7 +54,7 @@ impl Source for SineWave {
 
     #[inline]
     fn sample_rate(&self) -> SampleRate {
-        Self::SAMPLE_RATE
+        crate::DEFAULT_SAMPLE_RATE
     }
 
     #[inline]

src/source/square.rs

@@ -18,13 +18,11 @@ pub struct SquareWave {
 }
 
 impl SquareWave {
-    const SAMPLE_RATE: SampleRate = nz!(48000);
-
     /// The frequency of the sine.
     #[inline]
     pub fn new(freq: f32) -> SquareWave {
         SquareWave {
-            test_square: SignalGenerator::new(Self::SAMPLE_RATE, freq, Function::Square),
+            test_square: SignalGenerator::new(crate::DEFAULT_SAMPLE_RATE, freq, Function::Square),
         }
     }
 }
@@ -56,7 +54,7 @@ impl Source for SquareWave {
 
     #[inline]
     fn sample_rate(&self) -> SampleRate {
-        Self::SAMPLE_RATE
+        crate::DEFAULT_SAMPLE_RATE
     }
 
     #[inline]

src/source/triangle.rs

@@ -18,13 +18,11 @@ pub struct TriangleWave {
 }
 
 impl TriangleWave {
-    const SAMPLE_RATE: SampleRate = nz!(48000);
-
     /// The frequency of the sine.
     #[inline]
     pub fn new(freq: f32) -> TriangleWave {
         TriangleWave {
-            test_tri: SignalGenerator::new(Self::SAMPLE_RATE, freq, Function::Triangle),
+            test_tri: SignalGenerator::new(crate::DEFAULT_SAMPLE_RATE, freq, Function::Triangle),
         }
     }
 }
@@ -56,7 +54,7 @@ impl Source for TriangleWave {
 
     #[inline]
     fn sample_rate(&self) -> SampleRate {
-        Self::SAMPLE_RATE
+        crate::DEFAULT_SAMPLE_RATE
     }
 
     #[inline]

src/speakers/config.rs

@@ -108,7 +108,7 @@ impl Default for OutputConfig {
     fn default() -> Self {
         Self {
             channel_count: nz!(1),
-            sample_rate: nz!(44_100),
+            sample_rate: crate::DEFAULT_SAMPLE_RATE,
             buffer_size: BufferSize::default(),
             sample_format: cpal::SampleFormat::F32,
         }

src/stream.rs

@@ -30,8 +30,6 @@ use std::io::{Read, Seek};
 use std::marker::Sync;
 use std::num::NonZero;
 
-const HZ_44100: SampleRate = nz!(44_100);
-
 /// `cpal::Stream` container. Use `mixer()` method to control output.
 ///
 /// <div class="warning">When dropped playback will end, and the associated
@@ -128,7 +126,7 @@ impl Default for DeviceSinkConfig {
     fn default() -> Self {
         Self {
             channel_count: nz!(2),
-            sample_rate: HZ_44100,
+            sample_rate: crate::DEFAULT_SAMPLE_RATE,
             buffer_size: BufferSize::Default,
             sample_format: SampleFormat::F32,
         }
@@ -350,8 +348,8 @@ where
         self
     }
 
-    /// Set available parameters from a CPAL supported config. You can get a list of
-    /// such configurations for an output device using [crate::stream::supported_output_configs()]
+    /// Set available parameters from a CPAL supported config. To enumerate what a device supports,
+    /// use [`cpal::Device::supported_output_configs`].
     pub fn with_supported_config(
         mut self,
         config: &cpal::SupportedStreamConfig,
@@ -573,8 +571,11 @@ impl MixerDeviceSink {
     }
 }
 
-/// Return all formats supported by the device.
-pub fn supported_output_configs(
+/// Returns candidate output configurations for the device in preference order.
+///
+/// For each supported format, yields 48 kHz and 44.1 kHz (where the device supports them),
+/// followed by the device's maximum sample rate.
+fn supported_output_configs(
     device: &cpal::Device,
 ) -> Result<impl Iterator<Item = cpal::SupportedStreamConfig>, DeviceSinkError> {
     let mut supported: Vec<_> = device
@@ -586,12 +587,15 @@ pub fn supported_output_configs(
     Ok(supported.into_iter().flat_map(|sf| {
         let max_rate = sf.max_sample_rate();
         let min_rate = sf.min_sample_rate();
-        let mut formats = vec![sf.with_max_sample_rate()];
-        let preferred_rate = HZ_44100.get();
-        if preferred_rate < max_rate && preferred_rate > min_rate {
-            formats.push(sf.with_sample_rate(preferred_rate))
+        let mut formats = Vec::new();
+        for rate in [cpal::SAMPLE_RATE_48K, cpal::SAMPLE_RATE_CD] {
+            if rate >= min_rate && rate <= max_rate {
+                formats.push(sf.with_sample_rate(rate));
+            }
+        }
+        if !formats.iter().any(|f| f.sample_rate() == max_rate) {
+            formats.push(sf.with_max_sample_rate());
         }
-        formats.push(sf.with_sample_rate(min_rate));
         formats
     }))
 }