X-Git-Url: https://git.nihav.org/?a=blobdiff_plain;f=src%2Fio%2Fbitreader.rs;h=ea5f27c078d8c4e9cb3aa69bb69eeaa47e3d149e;hb=594ca5ca67fa9a7f47cac589925d8aa5106e3f7b;hp=20753d1561263e788a8d21d6815280c184dc979b;hpb=8ab3904ca48416131be683834f232175b8c76db5;p=nihav.git

diff --git a/src/io/bitreader.rs b/src/io/bitreader.rs
index 20753d1..ea5f27c 100644
--- a/src/io/bitreader.rs
+++ b/src/io/bitreader.rs
@@ -51,10 +51,10 @@ impl<'a> BitReader<'a> {
     }
 
     fn fill32le16(&mut self, src: &[u8]) {
-        let mut nw = (((src[1] as u32) << 24) |
-                      ((src[0] as u32) << 16) |
-                      ((src[3] as u32) <<  8) |
-                      ((src[2] as u32) <<  0)) as u64;
+        let nw = (((src[1] as u32) << 24) |
+                  ((src[0] as u32) << 16) |
+                  ((src[3] as u32) <<  8) |
+                  ((src[2] as u32) <<  0)) as u64;
         self.cache |= nw << (32 - self.bits);
     }
 
@@ -70,6 +70,7 @@ impl<'a> BitReader<'a> {
         }
     }
 
+    #[inline(always)]
     fn refill(&mut self) -> BitReaderResult<()> {
         if self.pos >= self.end { return Err(BitstreamEnd) }
         while self.bits <= 32 {
@@ -106,6 +107,7 @@ impl<'a> BitReader<'a> {
         Ok(())
     }
 
+    #[inline(always)]
     fn read_cache(&mut self, nbits: u8) -> u32 {
         let res = match self.mode {
             BitReaderMode::LE => ((1u64 << nbits) - 1) & self.cache,
@@ -122,6 +124,7 @@ impl<'a> BitReader<'a> {
         res as i32
     }
 
+    #[inline(always)]
     fn skip_cache(&mut self, nbits: u8) {
         match self.mode {
             BitReaderMode::LE => self.cache >>= nbits,
@@ -130,11 +133,13 @@ impl<'a> BitReader<'a> {
         self.bits -= nbits;
     }
 
+    #[inline(always)]
     fn reset_cache(&mut self) {
         self.bits = 0;
         self.cache = 0;
     }
 
+    #[inline(always)]
     pub fn read(&mut self, nbits: u8) -> BitReaderResult<u32> {
         if nbits == 0 { return Ok(0) }
         if nbits > 32 { return Err(TooManyBitsRequested) }
@@ -158,6 +163,7 @@ impl<'a> BitReader<'a> {
         Ok(res)
     }
 
+    #[inline(always)]
     pub fn read_bool(&mut self) -> BitReaderResult<bool> {
         if self.bits < 1 {
             if let Err(err) = self.refill() { return Err(err) }
@@ -168,12 +174,14 @@ impl<'a> BitReader<'a> {
         Ok(res == 1)
     }
 
+    #[inline(always)]
     pub fn peek(&mut self, nbits: u8) -> u32 {
         if nbits > 32 { return 0 }
         if self.bits < nbits { let _ = self.refill(); }
         self.read_cache(nbits)
     }
 
+    #[inline(always)]
     pub fn skip(&mut self, nbits: u32) -> BitReaderResult<()> {
         if self.bits as u32 >= nbits {
             self.skip_cache(nbits as u8);
@@ -196,6 +204,29 @@ impl<'a> BitReader<'a> {
         self.pos = ((nbits / 32) * 4) as usize;
         self.skip(nbits & 0x1F)
     }
+
+    pub fn align(&mut self) {
+        let pos = self.bits & 7;
+        if pos != 0 {
+            self.skip_cache(pos);
+        }
+    }
+}
+
+pub fn reverse_bits(inval: u32, len: u8) -> u32 {
+    if len == 0 { return 0; }
+    const REV_TAB: [u8; 16] = [
+        0b0000, 0b1000, 0b0100, 0b1100, 0b0010, 0b1010, 0b0110, 0b1110,
+        0b0001, 0b1001, 0b0101, 0b1101, 0b0011, 0b1011, 0b0111, 0b1111,
+    ];
+
+    let mut ret = 0;
+    let mut val = inval;
+    for _ in 0..8 {
+        ret = (ret << 4) | (REV_TAB[(val & 0xF) as usize] as u32);
+        val = val >> 4;
+    }
+    ret >> (32 - len)
 }
 
 #[cfg(test)]