binkaud: split out common data definitions for the future encoder

3 files changed, 38 insertions, 26 deletions

diff --git a/nihav-rad/src/codecs/binkaud.rs b/nihav-rad/src/codecs/binkaud.rs
index 7848e7e..b424c0e 100644
--- a/nihav-rad/src/codecs/binkaud.rs
+++ b/nihav-rad/src/codecs/binkaud.rs
@@ -2,17 +2,16 @@ use nihav_core::codecs::*;
 use nihav_codec_support::dsp::dct::*;
 use nihav_codec_support::dsp::fft::*;
 use nihav_core::io::bitreader::*;
-use std::f32::consts;
 use std::str::FromStr;
 
+use super::binkauddata::*;
+
 enum Transform {
     None,
     DCT(DCT),
     RDFT(RDFT),
 }
 
-const MAX_BANDS: usize = 25;
-
 struct BinkAudioDecoder {
     ainfo:      NAAudioInfo,
     chmap:      NAChannelMap,
@@ -60,10 +59,6 @@ fn overlap(a: &[f32], b: &[f32], dst: &mut [f32], len: usize, step: usize) {
 
 impl BinkAudioDecoder {
     fn new(use_dct: bool) -> Self {
-        let mut quants: [f32; 96] = [0.0; 96];
-        for i in 0..quants.len() {
-            quants[i] = ((i as f32) * 0.0664 / consts::LOG10_E).exp();
-        }
         Self {
             ainfo:      NAAudioInfo::new(0, 1, SND_F32P_FORMAT, 0),
             chmap:      NAChannelMap::new(),
@@ -71,7 +66,7 @@ impl BinkAudioDecoder {
             transform:  Transform::None,
             version_b:  false,
             len:        0,
-            quants,
+            quants:     get_quants_table(),
             bands:      [MAX_BANDS + 1; 26],
             num_bands:  0,
             duration:   0,
@@ -169,15 +164,6 @@ impl BinkAudioDecoder {
     }
 }
 
-const CRITICAL_FREQS: [usize; MAX_BANDS] = [
-      100,   200,  300,  400,  510,  630,   770,   920,
-     1080,  1270, 1480, 1720, 2000, 2320,  2700,  3150,
-     3700,  4400, 5300, 6400, 7700, 9500, 12000, 15500,
-    24500
-];
-
-const RUN_TAB: [usize; 16] = [ 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16, 32, 64 ];
-
 impl NADecoder for BinkAudioDecoder {
     fn init(&mut self, _supp: &mut NADecoderSupport, info: NACodecInfoRef) -> DecoderResult<()> {
         if let NACodecTypeInfo::Audio(ainfo) = info.get_properties() {
@@ -214,15 +200,7 @@ impl NADecoder for BinkAudioDecoder {
                     (2.0 / (self.len as f32)).sqrt() / 1024.0
                 };
             let s_srate = if single { srate } else { srate >> 1 } as usize;
-            self.num_bands = 1;
-            while self.num_bands < CRITICAL_FREQS.len() && CRITICAL_FREQS[self.num_bands - 1] < s_srate {
-                self.num_bands += 1;
-            }
-            self.bands[0] = 2;
-            for i in 1..self.num_bands {
-                self.bands[i] = (CRITICAL_FREQS[i - 1] * self.len / s_srate) & !1;
-            }
-            self.bands[self.num_bands] = self.len;
+            init_bands(s_srate, self.len, &mut self.num_bands, &mut self.bands);
             self.first_frm = true;
 
             Ok(())
diff --git a/nihav-rad/src/codecs/binkauddata.rs b/nihav-rad/src/codecs/binkauddata.rs
new file mode 100644
index 0000000..1cdce60
--- /dev/null
+++ b/nihav-rad/src/codecs/binkauddata.rs
@@ -0,0 +1,32 @@
+use std::f32::consts;
+
+pub const MAX_BANDS: usize = 25;
+
+const CRITICAL_FREQS: [usize; MAX_BANDS] = [
+      100,   200,  300,  400,  510,  630,   770,   920,
+     1080,  1270, 1480, 1720, 2000, 2320,  2700,  3150,
+     3700,  4400, 5300, 6400, 7700, 9500, 12000, 15500,
+    24500
+];
+
+pub const RUN_TAB: [usize; 16] = [ 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16, 32, 64 ];
+
+pub fn init_bands(srate: usize, len: usize, num_bands: &mut usize, bands: &mut [usize; MAX_BANDS + 1]) {
+    *num_bands = 1;
+    while *num_bands < CRITICAL_FREQS.len() && CRITICAL_FREQS[*num_bands - 1] < srate {
+        *num_bands += 1;
+    }
+    bands[0] = 2;
+    for i in 1..*num_bands {
+        bands[i] = (CRITICAL_FREQS[i - 1] * len / srate) & !1;
+    }
+    bands[*num_bands] = len;
+}
+
+pub fn get_quants_table() -> [f32; 96] {
+    let mut quants: [f32; 96] = [0.0; 96];
+    for i in 0..quants.len() {
+        quants[i] = ((i as f32) * 0.0664 / consts::LOG10_E).exp();
+    }
+    quants
+}
diff --git a/nihav-rad/src/codecs/mod.rs b/nihav-rad/src/codecs/mod.rs
index 14db405..e8fbe86 100644
--- a/nihav-rad/src/codecs/mod.rs
+++ b/nihav-rad/src/codecs/mod.rs
@@ -13,6 +13,8 @@ macro_rules! validate {
 mod smacker;
 #[cfg(feature="decoder_binkaud")]
 mod binkaud;
+#[cfg(feature="decoder_binkaud")]
+mod binkauddata;
 #[cfg(feature="decoder_binkvid")]
 mod binkvid;
 #[cfg(any(feature="decoder_binkvid", feature="encoder_binkvid"))]