Iterate over samples

src/Tools/fileconv/Cargo.toml

@@ -9,6 +9,7 @@ panic = "abort"
 [dependencies]
 clap        = {version = "4.4.11", features = ["derive"]}
 image       = "0.24.7"
+hound       = "3.5.1"
 paste       = "1.0.14"
 png         = "0.17.10"
 tool_helper = {path = "../tool_helper"}

src/Tools/fileconv/src/audio/my_vag/mod.rs

@@ -1,6 +1,35 @@
+pub mod types;
+
 use std::io::Write;
 use tool_helper::{Error, Input};
+use types::MonoADPCMIterator;
 
-pub fn convert(_input: Input, _output: &mut dyn Write) -> Result<(), Error> {
+pub fn convert(input: Input, _output: &mut dyn Write) -> Result<(), Error> {
+    let mut wav_file   = hound::WavReader::new(input)?;
+    let     wav_header = wav_file.spec();
+
+    validate(&wav_header)?;
+    let mut sample_count = 0;
+    for _adpcm_samples in MonoADPCMIterator::create(wav_file.samples::<i16>()) {
+        sample_count += 1;
+    }
+
+    println!("Parsed {} vag samples", sample_count);
     Err(Error::not_implemented("my vag convert"))
+}
+
+fn validate(wav_header: &hound::WavSpec) -> Result<(), Error> {
+    if wav_header.sample_format != hound::SampleFormat::Int {
+        return Err(Error::from_str("VAG: Only integer samples are supported as input."));
+    }
+
+    if wav_header.bits_per_sample != 16 {
+        return Err(Error::from_str("VAG: Only 16bits samples are currently supported as input."));
+    }
+
+    if wav_header.channels != 1 {
+        return Err(Error::from_str("VAG: Only mono samples are currently supported"));
+    }
+
+    Ok(())
 }

src/Tools/fileconv/src/audio/my_vag/types.rs

@@ -0,0 +1,45 @@
+use tool_helper::Error;
+
+pub struct VAGADPCM {
+    data: [u32; 4]
+}
+
+impl VAGADPCM {
+    const ADPCM_SAMPLES_PER_VAGADPCM:usize = 28;
+
+    pub fn create() -> VAGADPCM {
+        VAGADPCM{data: [0; 4]}
+    }
+}
+
+pub struct MonoADPCMIterator<I: std::iter::Iterator<Item=Result<i16, hound::Error>>> {
+    iter: I
+}
+
+impl<I:std::iter::Iterator<Item=Result<i16, hound::Error>>> MonoADPCMIterator<I>{
+    pub fn create(iter: I) -> MonoADPCMIterator<I> {
+        MonoADPCMIterator{iter}
+    }
+}
+
+impl<I:std::iter::Iterator<Item=Result<i16, hound::Error>>> std::iter::Iterator for MonoADPCMIterator<I> {
+    type Item = Result<[i16; VAGADPCM::ADPCM_SAMPLES_PER_VAGADPCM], Error>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        const STREAM_GONE_ERROR: &'static str = "Reading ADPCM sample failed";
+
+        if let Some(next_sample) = self.iter.next() {
+            let Ok(next_sample) = next_sample else {return Some(Err(Error::from_str(STREAM_GONE_ERROR)));};
+
+            let mut sample = [0;VAGADPCM::ADPCM_SAMPLES_PER_VAGADPCM];
+            sample[0] = next_sample;
+
+            for idx in 1..VAGADPCM::ADPCM_SAMPLES_PER_VAGADPCM {
+                let Ok(next_sample) = self.iter.next().unwrap_or(Ok(0)) else {return Some(Err(Error::from_str(STREAM_GONE_ERROR)));};
+                sample[idx] = next_sample;
+            }
+            return Some(Ok(sample));
+        }
+        None
+    }
+}