Merge pull request #11 from EaterLabs/misc-fixes

implement basic f32le support and some other misc fixes

src/errors.rs

@@ -1,4 +1,5 @@
-use std::io;
+use std::{fmt::{Debug,Display}, io};
+use std::error::Error as StdError;
 use super::fourcc::FourCC;
 
 use uuid;
@@ -43,6 +44,14 @@ pub enum Error {
 
 }
 
+impl StdError for Error {}
+
+impl Display for Error {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        Debug::fmt(self, f)
+    }
+}
+
 
 impl From<io::Error> for Error {
     fn from(error: io::Error) -> Error {

src/fmt.rs

@@ -18,6 +18,7 @@ use byteorder::{WriteBytesExt, ReadBytesExt};
 /// `AudioProgramme`.
 /// 
 /// See BS.2088-1 § 8, also BS.2094, also blahblahblah...
+#[derive(Debug)]
 pub struct ADMAudioID {
     pub track_uid: [char; 12],
     pub channel_format_ref: [char; 14],
@@ -28,6 +29,7 @@ pub struct ADMAudioID {
 /// 
 /// This information is correlated from the Wave format ChannelMap field and
 /// the `chna` chunk, if present.
+#[derive(Debug)]
 pub struct ChannelDescriptor {
     /// Index, the offset of this channel's samples in one frame.
     pub index: u16,

src/wavereader.rs

@@ -50,7 +50,7 @@ impl<R: Read + Seek> AudioFrameReader<R> {
             "Unable to read audio frames from packed formats: block alignment is {}, should be {}",
             format.block_alignment, (format.bits_per_sample / 8 ) * format.channel_count);
         
-        assert!(format.common_format() == CommonFormat::IntegerPCM , 
+        assert!(format.common_format() == CommonFormat::IntegerPCM || format.common_format() == CommonFormat::IeeeFloatPCM, 
                 "Unsupported format tag {:?}", format.tag);
         
         inner.seek(Start(start))?;
@@ -121,8 +121,27 @@ impl<R: Read + Seek> AudioFrameReader<R> {
         }
     }
 
-    pub fn read_float_frame(&mut self, buffer:&mut [f32]) -> Result<u64, Error> {
+    pub fn read_float_frame(&mut self, buffer: &mut [f32]) -> Result<u64, Error> {
-        todo!()
+        assert!(buffer.len() as u16 == self.format.channel_count,
+            "read_float_frame was called with a mis-sized buffer, expected {}, was {}",
+            self.format.channel_count, buffer.len());
+
+        let framed_bits_per_sample = self.format.block_alignment * 8 / self.format.channel_count;
+
+        let tell = self.inner.seek(Current(0))?;
+
+        if (tell - self.start) < self.length {
+            for n in 0..(self.format.channel_count as usize) {
+                buffer[n] = match (self.format.bits_per_sample, framed_bits_per_sample) {
+                    (25..=32,32) => self.inner.read_f32::<LittleEndian>()?,
+                    (b,_)=> panic!("Unrecognized integer format, bits per sample {}, channels {}, block_alignment {}",
+                        b, self.format.channel_count, self.format.block_alignment)
+                }
+            }
+            Ok( 1 )
+        } else {
+            Ok( 0 )
+        }
     }
 }