+//! Output frame reordering.
+//!
+//! NihAV decoders output frames in the same order as they are put in.
+//! In result if you want to have frames in display order you might need some frame reorderer.
+//! This module provides such functionality depending on codec type: audio codecs and video codecs without B-frames do not need any reorderer and can use `NoReorderer` if the common interface is required. Codecs with B-frames should use `IPBReorderer`. For codecs with very complex reordering rules like H.264 or H.256 `PictureIDReorderer` will be added eventually.
+//!
+//! You can find out required reorderer by quering codec properties using `nihav_core::register` module.
use std::mem::swap;
pub use crate::frame::{FrameType, NAFrameRef};
+/// A trait for frame reorderer.
pub trait FrameReorderer {
+ /// Stores a newly decoded frame.
fn add_frame(&mut self, fref: NAFrameRef) -> bool;
+ /// Gets the next frame to be displayed (or `None` if that is not possible).
fn get_frame(&mut self) -> Option<NAFrameRef>;
+ /// Clears all stored frames.
fn flush(&mut self);
+ /// Retrieves the last frames stored by the reorderer.
fn get_last_frames(&mut self) -> Option<NAFrameRef>;
}
+/// Zero reorderer.
pub struct NoReorderer {
fref: Option<NAFrameRef>,
}
impl NoReorderer {
+ /// Constructs a new instance of `NoReorderer`.
pub fn new() -> Self {
Self { fref: None }
}
}
+impl Default for NoReorderer {
+ fn default() -> Self {
+ Self::new()
+ }
+}
+
impl FrameReorderer for NoReorderer {
fn add_frame(&mut self, fref: NAFrameRef) -> bool {
if self.fref.is_none() {
fn get_last_frames(&mut self) -> Option<NAFrameRef> { None }
}
+/// Frame reorderer for codecs with I/P/B frames.
+#[derive(Default)]
pub struct IPBReorderer {
- frames: Vec<NAFrameRef>,
- max_depth: usize,
- last_ft: FrameType,
+ rframe: Option<NAFrameRef>,
+ bframe: Option<NAFrameRef>,
}
impl IPBReorderer {
- pub fn new(max_depth: usize) -> Self {
- Self {
- frames: Vec::with_capacity(max_depth),
- max_depth,
- last_ft: FrameType::Other,
+ /// Constructs a new instance of `IPBReorderer`.
+ pub fn new() -> Self { Self::default() }
+}
+
+impl FrameReorderer for IPBReorderer {
+ fn add_frame(&mut self, fref: NAFrameRef) -> bool {
+ if self.rframe.is_some() && self.bframe.is_some() { return false; }
+ let is_b = fref.get_frame_type() == FrameType::B;
+ if is_b && self.bframe.is_some() { return false; }
+ if is_b {
+ self.bframe = Some(fref);
+ } else {
+ std::mem::swap(&mut self.bframe, &mut self.rframe);
+ self.rframe = Some(fref);
+ }
+ true
+ }
+ fn get_frame(&mut self) -> Option<NAFrameRef> {
+ let mut ret = None;
+ if self.bframe.is_some() {
+ std::mem::swap(&mut ret, &mut self.bframe);
+ }
+ ret
+ }
+ fn flush(&mut self) {
+ self.rframe = None;
+ self.bframe = None;
+ }
+ fn get_last_frames(&mut self) -> Option<NAFrameRef> {
+ let mut ret = None;
+ if self.bframe.is_some() {
+ std::mem::swap(&mut ret, &mut self.bframe);
+ } else if self.rframe.is_some() {
+ std::mem::swap(&mut ret, &mut self.rframe);
}
+ ret
}
}
-impl FrameReorderer for IPBReorderer {
+/// Frame reorderer for codecs with complex I/P/B frame structure like ITU H.26x.
+#[derive(Default)]
+pub struct ComplexReorderer {
+ last_ref_dts: Option<u64>,
+ ready_idx: usize,
+ frames: Vec<NAFrameRef>,
+}
+
+impl ComplexReorderer {
+ /// Constructs a new instance of `IPBReorderer`.
+ pub fn new() -> Self { Self::default() }
+}
+
+impl FrameReorderer for ComplexReorderer {
fn add_frame(&mut self, fref: NAFrameRef) -> bool {
- if self.frames.len() < self.max_depth {
- let cur_ft = fref.get_frame_type();
- if cur_ft != FrameType::B {
+ if self.frames.len() >= 64 {
+ return false;
+ }
+ let is_ref = fref.frame_type == FrameType::I || fref.frame_type == FrameType::P;
+ if !is_ref {
+ if self.frames.is_empty() || fref.get_dts().is_none() {
self.frames.push(fref);
- self.last_ft = cur_ft;
- } else {
- let pframe = self.frames.pop();
- if pframe.is_some() {
- self.frames.push(fref);
- self.frames.push(pframe.unwrap());
- } else {
- self.last_ft = cur_ft;
+ } else if let Some(new_dts) = fref.get_dts() {
+ let mut idx = 0;
+ for (i, frm) in self.frames.iter().enumerate() {
+ idx = i;
+ if let Some(dts) = frm.get_dts() {
+ if dts > new_dts {
+ break;
+ }
+ }
}
+ self.frames.insert(idx, fref);
}
- true
} else {
- false
+ for (i, frm) in self.frames.iter().enumerate() {
+ if frm.get_dts() == self.last_ref_dts {
+ self.ready_idx = i + 1;
+ }
+ }
+ self.last_ref_dts = fref.get_dts();
+ self.frames.push(fref);
}
+ true
}
fn get_frame(&mut self) -> Option<NAFrameRef> {
- if !self.frames.is_empty() {
+ if self.ready_idx > 0 {
+ self.ready_idx -= 1;
Some(self.frames.remove(0))
} else {
None
}
}
fn flush(&mut self) {
+ self.last_ref_dts = None;
+ self.ready_idx = 0;
self.frames.clear();
- self.last_ft = FrameType::Other;
}
fn get_last_frames(&mut self) -> Option<NAFrameRef> {
- self.get_frame()
+ if !self.frames.is_empty() {
+ Some(self.frames.remove(0))
+ } else {
+ None
+ }
}
}
projects / nihav.git / blobdiff