Merge pull request #11 from AkiyukiOkayasu/develop

Add rewind() to IMA-ADPCM player

benches/bench.rs

@@ -27,13 +27,20 @@ fn read_sample(c: &mut Criterion) {
 }
 
 fn parse_decode_ima_adpcm(c: &mut Criterion) {
-    let data = include_bytes!("../tests/resources/Sine440Hz_1ch_48000Hz_4bit_IMAADPCM.wav");
-    let mut player = ImaAdpcmPlayer::new(data);
+    let data = include_bytes!("../tests/resources/Sine440Hz_2ch_48000Hz_4bit_IMAADPCM.wav");
     let mut buffer: [i16; 2] = [0i16, 0i16];
 
     c.bench_function("Decode IMA-ADPCM", |b| {
+        let mut player = ImaAdpcmPlayer::new(data);
         let buf = buffer.as_mut_slice();
-        b.iter(|| player.get_next_frame(buf))
+        b.iter(|| {
+            // player = ImaAdpcmPlayer::new(data);
+            player.rewind();
+            for _ in 0..192000 {
+                //4sec
+                player.get_next_frame(buf).unwrap();
+            }
+        })
     });
 }
 

src/imaadpcm.rs

@@ -217,6 +217,19 @@ impl<'a> ImaAdpcmPlayer<'a> {
             self.reading_block = block;
         }
     }
+
+    /// 再生位置を先頭に戻します.
+    pub fn rewind(&mut self) {
+        self.frame_index = 0;
+        if !self.reading_block.is_empty() {
+            self.reading_block = &self.reading_block[0..0]; //reading_blockを空のスライスにする
+        }
+        for q in &mut self.nibble_queue {
+            for i in 0..q.len() {
+                q.dequeue().unwrap();
+            }
+        }
+    }
 }
 
 /// IMA-ADPCMのBlockのData word（32bit長）を8つのnibble(4bit長)にパースする.

src/wav.rs

@@ -130,7 +130,6 @@ pub(super) fn parse_fmt(input: &[u8]) -> IResult<&[u8], WavFmtSpecs> {
 
     if audio_format == AudioFormat::ImaAdpcmLe {
         //IMA-ADPCMの拡張属性の取得
-        println!("block size: {}", block_size);
         let num_block_align = block_size;
         assert!(block_size % 4 == 0);
         assert!(input.len() >= 4);

tests/integration_test.rs

@@ -3340,6 +3340,18 @@ fn ima_adpcm_4bit_play_to_end() {
     //Error
     let e = player.get_next_frame(buf);
     assert!(e.is_err());
+
+    //再生位置を先頭に戻す
+    player.rewind();
+
+    // Play to the end
+    for _ in 0..spec.num_samples {
+        player.get_next_frame(buf).unwrap();
+    }
+
+    //Error
+    let e = player.get_next_frame(buf);
+    assert!(e.is_err());
 }
 
 #[test]
@@ -3389,4 +3401,16 @@ fn ima_adpcm_4bit_2ch_play_to_end() {
     // Error
     let e = player.get_next_frame(buf);
     assert!(e.is_err());
+
+    // 再生位置を先頭に戻す.
+    player.rewind();
+
+    // Play to the end
+    for _ in 0..spec.num_samples {
+        player.get_next_frame(buf).unwrap();
+    }
+
+    // Error
+    let e = player.get_next_frame(buf);
+    assert!(e.is_err());
 }