nihav-codec-support/src/codecs/mod.rs

   1 //! Decoder support functions and definitions.
   2 use std::fmt;
   3 use std::ops::{Add, AddAssign, Sub, SubAssign};
   4
   5 pub use nihav_core::frame::*;
   6 use std::mem;
   7
   8 /// Frame manager for hold-and-modify codecs.
   9 ///
  10 /// This frame manager simplifies frame management for the case when codec decodes new frame by updating parts of the previous frame.
  11 ///
  12 /// # Examples
  13 ///
  14 /// ````norun
  15 /// let mut frame = if is_intra_frame {
  16 ///         allocate_video_frame()
  17 ///     } else {
  18 ///         let ret = shuffler.clone_ref();
  19 ///         if ret.is_none() {
  20 ///             return Err(DecodingError::MissingReference);
  21 ///         }
  22 ///         ret.unwrap()
  23 ///     };
  24 /// // output data into the frame
  25 /// shuffler.add_frame(frame.clone()); // tells frame manager to use the frame as the next reference
  26 /// ````
  27 #[allow(dead_code)]
  28 pub struct HAMShuffler<T: Copy> {
  29     lastframe: Option<NAVideoBufferRef<T>>,
  30 }
  31
  32 impl<T: Copy> HAMShuffler<T> {
  33     /// Constructs a new instance of frame manager.
  34     #[allow(dead_code)]
  35     pub fn new() -> Self { HAMShuffler { lastframe: None } }
  36     /// Clears the reference.
  37     #[allow(dead_code)]
  38     pub fn clear(&mut self) { self.lastframe = None; }
  39     /// Sets a new frame reference.
  40     #[allow(dead_code)]
  41     pub fn add_frame(&mut self, buf: NAVideoBufferRef<T>) {
  42         self.lastframe = Some(buf);
  43     }
  44     /// Provides a copy of the reference frame if present or `None` if it is not.
  45     #[allow(dead_code)]
  46     pub fn clone_ref(&mut self) -> Option<NAVideoBufferRef<T>> {
  47         if let Some(ref mut frm) = self.lastframe {
  48             let newfrm = frm.copy_buffer();
  49             *frm = newfrm.clone().into_ref();
  50             Some(newfrm.into_ref())
  51         } else {
  52             None
  53         }
  54     }
  55     /// Returns the original saved reference frame or `None` if it is not present.
  56     #[allow(dead_code)]
  57     pub fn get_output_frame(&mut self) -> Option<NAVideoBufferRef<T>> {
  58         match self.lastframe {
  59             Some(ref frm) => Some(frm.clone()),
  60             None => None,
  61         }
  62     }
  63 }
  64
  65 impl<T: Copy> Default for HAMShuffler<T> {
  66     fn default() -> Self { Self { lastframe: None } }
  67 }
  68
  69 /// Frame manager for codecs with intra and inter frames.
  70 ///
  71 /// This frame manager simplifies frame management for the case when codec decodes new frame using previous frame as source of some data.
  72 ///
  73 /// # Examples
  74 ///
  75 /// ````norun
  76 /// let mut frame = allocate_video_frame();
  77 /// if is_inter_frame {
  78 ///     let ret = shuffler.get_ref();
  79 ///     if ret.is_none() {
  80 ///         return Err(DecodingError::MissingReference);
  81 ///     }
  82 ///     let ref_frame = ret.unwrap();
  83 ///     // keep decoding using data from ref_frame
  84 /// }
  85 /// shuffler.add_frame(frame.clone()); // tells frame manager to use the frame as the next reference
  86 /// ````
  87 #[allow(dead_code)]
  88 pub struct IPShuffler {
  89     lastframe: Option<NAVideoBufferRef<u8>>,
  90 }
  91
  92 impl IPShuffler {
  93     /// Constructs a new instance of frame manager.
  94     #[allow(dead_code)]
  95     pub fn new() -> Self { IPShuffler { lastframe: None } }
  96     /// Clears the reference.
  97     #[allow(dead_code)]
  98     pub fn clear(&mut self) { self.lastframe = None; }
  99     /// Sets a new frame reference.
 100     #[allow(dead_code)]
 101     pub fn add_frame(&mut self, buf: NAVideoBufferRef<u8>) {
 102         self.lastframe = Some(buf);
 103     }
 104     /// Returns the original saved reference frame or `None` if it is not present.
 105     #[allow(dead_code)]
 106     pub fn get_ref(&mut self) -> Option<NAVideoBufferRef<u8>> {
 107         if let Some(ref frm) = self.lastframe {
 108             Some(frm.clone())
 109         } else {
 110             None
 111         }
 112     }
 113 }
 114
 115 impl Default for IPShuffler {
 116     fn default() -> Self { Self { lastframe: None } }
 117 }
 118
 119 /// Frame manager for codecs with I-, P- and B-frames.
 120 ///
 121 /// This frame manager simplifies frame management for the case when codec uses I/P/B frame scheme.
 122 ///
 123 /// # Examples
 124 ///
 125 /// ````norun
 126 /// let mut frame = allocate_video_frame();
 127 /// for mb in all_macroblocks {
 128 ///     // decode macroblock type
 129 ///     match mb_type {
 130 ///         MBType::Inter => {
 131 ///             do_mc(&mut frame, shuffler.get_lastref().unwrap());
 132 ///         },
 133 ///         MBType::BForward => {
 134 ///             do_mc(&mut frame, shuffler.get_b_fwdref().unwrap());
 135 ///         },
 136 ///         MBType::BBackward => {
 137 ///             do_mc(&mut frame, shuffler.get_b_bwdref().unwrap());
 138 ///         },
 139 ///         // handle the rest of cases
 140 ///     };
 141 /// if is_random_access_frame {
 142 ///     shuffler.clear(); // remove all saved references
 143 /// }
 144 /// if is_intra_frame || is_p_frame {
 145 ///     shuffler.add_frame(frame.clone()); // tells frame manager to use the frame as the next reference
 146 /// }
 147 /// ````
 148 #[allow(dead_code)]
 149 pub struct IPBShuffler {
 150     lastframe: Option<NAVideoBufferRef<u8>>,
 151     nextframe: Option<NAVideoBufferRef<u8>>,
 152 }
 153
 154 impl IPBShuffler {
 155     /// Constructs a new instance of frame manager.
 156     #[allow(dead_code)]
 157     pub fn new() -> Self { IPBShuffler { lastframe: None, nextframe: None } }
 158     /// Clears the reference.
 159     #[allow(dead_code)]
 160     pub fn clear(&mut self) { self.lastframe = None; self.nextframe = None; }
 161     /// Sets a new frame reference.
 162     #[allow(dead_code)]
 163     pub fn add_frame(&mut self, buf: NAVideoBufferRef<u8>) {
 164         mem::swap(&mut self.lastframe, &mut self.nextframe);
 165         self.lastframe = Some(buf);
 166     }
 167     /// Returns the previous reference frame or `None` if it is not present.
 168     #[allow(dead_code)]
 169     pub fn get_lastref(&mut self) -> Option<NAVideoBufferRef<u8>> {
 170         if let Some(ref frm) = self.lastframe {
 171             Some(frm.clone())
 172         } else {
 173             None
 174         }
 175     }
 176     /// Returns second last reference frame or `None` if it is not present.
 177     #[allow(dead_code)]
 178     pub fn get_nextref(&mut self) -> Option<NAVideoBufferRef<u8>> {
 179         if let Some(ref frm) = self.nextframe {
 180             Some(frm.clone())
 181         } else {
 182             None
 183         }
 184     }
 185     /// Returns the temporally following reference for B-frame or `None` if it is not present.
 186     #[allow(dead_code)]
 187     pub fn get_b_fwdref(&mut self) -> Option<NAVideoBufferRef<u8>> {
 188         if let Some(ref frm) = self.nextframe {
 189             Some(frm.clone())
 190         } else {
 191             None
 192         }
 193     }
 194     /// Returns the temporally preceeding reference for B-frame or `None` if it is not present.
 195     #[allow(dead_code)]
 196     pub fn get_b_bwdref(&mut self) -> Option<NAVideoBufferRef<u8>> {
 197         if let Some(ref frm) = self.lastframe {
 198             Some(frm.clone())
 199         } else {
 200             None
 201         }
 202     }
 203 }
 204
 205 impl Default for IPBShuffler {
 206     fn default() -> Self { Self { lastframe: None, nextframe: None } }
 207 }
 208
 209 /// Motion vector data type.
 210 ///
 211 /// # Examples
 212 ///
 213 /// ```
 214 /// use nihav_codec_support::codecs::MV;
 215 ///
 216 /// let mv0 = MV::new(1, 3);
 217 /// let mv1 = MV { x: 2, y: 3 }; // choose whatever style you prefer
 218 /// let mv2 = mv1 - mv0;
 219 /// let mv_pred = MV::pred(mv0, mv1, mv2); // get median prediction for the vectors (1, 0)
 220 /// ```
 221 #[derive(Debug,Clone,Copy,Default,PartialEq)]
 222 pub struct MV {
 223     /// X coordinate of the vector.
 224     pub x: i16,
 225     /// Y coordinate of the vector.
 226     pub y: i16,
 227 }
 228
 229 #[allow(clippy::many_single_char_names)]
 230 #[allow(clippy::collapsible_if)]
 231 impl MV {
 232     /// Creates a new motion vector instance.
 233     pub fn new(x: i16, y: i16) -> Self { MV{ x, y } }
 234     /// Predicts median from provided motion vectors.
 235     ///
 236     /// Each component of the vector is predicted as the median of corresponding input vector components.
 237     pub fn pred(a: MV, b: MV, c: MV) -> Self {
 238         let x;
 239         if a.x < b.x {
 240             if b.x < c.x {
 241                 x = b.x;
 242             } else {
 243                 if a.x < c.x { x = c.x; } else { x = a.x; }
 244             }
 245         } else {
 246             if b.x < c.x {
 247                 if a.x < c.x { x = a.x; } else { x = c.x; }
 248             } else {
 249                 x = b.x;
 250             }
 251         }
 252         let y;
 253         if a.y < b.y {
 254             if b.y < c.y {
 255                 y = b.y;
 256             } else {
 257                 if a.y < c.y { y = c.y; } else { y = a.y; }
 258             }
 259         } else {
 260             if b.y < c.y {
 261                 if a.y < c.y { y = a.y; } else { y = c.y; }
 262             } else {
 263                 y = b.y;
 264             }
 265         }
 266         MV { x, y }
 267     }
 268 }
 269
 270 /// Zero motion vector.
 271 pub const ZERO_MV: MV = MV { x: 0, y: 0 };
 272
 273 impl Add for MV {
 274     type Output = MV;
 275     fn add(self, other: MV) -> MV { MV { x: self.x + other.x, y: self.y + other.y } }
 276 }
 277
 278 impl AddAssign for MV {
 279     fn add_assign(&mut self, other: MV) { self.x += other.x; self.y += other.y; }
 280 }
 281
 282 impl Sub for MV {
 283     type Output = MV;
 284     fn sub(self, other: MV) -> MV { MV { x: self.x - other.x, y: self.y - other.y } }
 285 }
 286
 287 impl SubAssign for MV {
 288     fn sub_assign(&mut self, other: MV) { self.x -= other.x; self.y -= other.y; }
 289 }
 290
 291 impl fmt::Display for MV {
 292     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
 293         write!(f, "{},{}", self.x, self.y)
 294     }
 295 }
 296
 297 #[cfg(any(feature="blockdsp"))]
 298 pub mod blockdsp;
 299
 300 #[cfg(feature="h263")]
 301 #[allow(clippy::collapsible_if)]
 302 #[allow(clippy::manual_memcpy)]
 303 #[allow(clippy::needless_range_loop)]
 304 pub mod h263;
 305
 306 /// The common 8x8 zigzag scan.
 307 pub const ZIGZAG: [usize; 64] = [
 308      0,  1,  8, 16,  9,  2,  3, 10,
 309     17, 24, 32, 25, 18, 11,  4,  5,
 310     12, 19, 26, 33, 40, 48, 41, 34,
 311     27, 20, 13,  6,  7, 14, 21, 28,
 312     35, 42, 49, 56, 57, 50, 43, 36,
 313     29, 22, 15, 23, 30, 37, 44, 51,
 314     58, 59, 52, 45, 38, 31, 39, 46,
 315     53, 60, 61, 54, 47, 55, 62, 63
 316 ];
 317
 318 pub mod imaadpcm;