nihav-core/src/reorder.rs

   1 use std::mem::swap;
   2 pub use crate::frame::{FrameType, NAFrameRef};
   3
   4 pub trait FrameReorderer {
   5     fn add_frame(&mut self, fref: NAFrameRef) -> bool;
   6     fn get_frame(&mut self) -> Option<NAFrameRef>;
   7     fn flush(&mut self);
   8     fn get_last_frames(&mut self) -> Option<NAFrameRef>;
   9 }
  10
  11 pub struct NoReorderer {
  12     fref:   Option<NAFrameRef>,
  13 }
  14
  15 impl NoReorderer {
  16     pub fn new() -> Self {
  17         Self { fref: None }
  18     }
  19 }
  20
  21 impl FrameReorderer for NoReorderer {
  22     fn add_frame(&mut self, fref: NAFrameRef) -> bool {
  23         if self.fref.is_none() {
  24             self.fref = Some(fref);
  25             true
  26         } else {
  27             false
  28         }
  29     }
  30     fn get_frame(&mut self) -> Option<NAFrameRef> {
  31         let mut ret = None;
  32         swap(&mut ret, &mut self.fref);
  33         ret
  34     }
  35     fn flush(&mut self) { self.fref = None; }
  36     fn get_last_frames(&mut self) -> Option<NAFrameRef> { None }
  37 }
  38
  39 #[derive(Default)]
  40 pub struct IPBReorderer {
  41     rframe:     Option<NAFrameRef>,
  42     bframe:     Option<NAFrameRef>,
  43 }
  44
  45 impl IPBReorderer {
  46     pub fn new() -> Self { Self::default() }
  47 }
  48
  49 impl FrameReorderer for IPBReorderer {
  50     fn add_frame(&mut self, fref: NAFrameRef) -> bool {
  51         if self.rframe.is_some() && self.bframe.is_some() { return false; }
  52         let is_b = fref.get_frame_type() == FrameType::B;
  53         if is_b && self.bframe.is_some() { return false; }
  54         if is_b {
  55             self.bframe = Some(fref);
  56         } else {
  57             std::mem::swap(&mut self.bframe, &mut self.rframe);
  58             self.rframe = Some(fref);
  59         }
  60         true
  61     }
  62     fn get_frame(&mut self) -> Option<NAFrameRef> {
  63         let mut ret = None;
  64         if self.bframe.is_some() {
  65             std::mem::swap(&mut ret, &mut self.bframe);
  66         }
  67         ret
  68     }
  69     fn flush(&mut self) {
  70         self.rframe = None;
  71         self.bframe = None;
  72     }
  73     fn get_last_frames(&mut self) -> Option<NAFrameRef> {
  74         let mut ret = None;
  75         if self.bframe.is_some() {
  76             std::mem::swap(&mut ret, &mut self.bframe);
  77         } else if self.rframe.is_some() {
  78             std::mem::swap(&mut ret, &mut self.rframe);
  79         }
  80         ret
  81     }
  82 }
  83