Struct cros_codecs::decoders::vp9::decoder::Decoder

pub struct Decoder<T: DecodedHandle> {
    parser: Parser,
    blocking_mode: BlockingMode,
    backend: Box<dyn StatelessDecoderBackend<Handle = T>>,
    negotiation_status: NegotiationStatus,
    coded_resolution: Resolution,
    ready_queue: Vec<T>,
    current_display_order: u64,
    reference_frames: [Option<T>; 8],
    segmentation: [Segmentation; 8],
    bit_depth: BitDepth,
    profile: Profile,
}

Fields

parser: Parser

A parser to extract bitstream data and build frame data in turn

blocking_mode: BlockingMode

Whether the decoder should block on decode operations.

backend: Box<dyn StatelessDecoderBackend<Handle = T>>

The backend used for hardware acceleration.

negotiation_status: NegotiationStatus

Keeps track of whether the decoded format has been negotiated with the backend.

coded_resolution: Resolution

The current resolution

ready_queue: Vec<T>

A queue with the pictures that are ready to be sent to the client.

current_display_order: u64

A monotonically increasing counter used to tag pictures in display order

reference_frames: [Option<T>; 8]

The reference frames in use.

segmentation: [Segmentation; 8]

Per-segment data.

bit_depth: BitDepth

Cached value for bit depth

profile: Profile

Cached value for profile

Implementations

impl Decoder<VADecodedHandle>

pub fn new_vaapi(
    display: Rc<Display>,
    blocking_mode: BlockingMode
) -> Result<Self>

impl<T: DecodedHandle + DynDecodedHandle + 'static> Decoder<T>

pub(crate) fn new(
    backend: Box<dyn StatelessDecoderBackend<Handle = T>>,
    blocking_mode: BlockingMode
) -> Result<Self>

Create a new codec backend for VP8.

fn replace_reference(reference: &mut Option<T>, handle: &T)

Replace a reference frame with handle.

fn update_references(
    reference_frames: &mut [Option<T>; 8],
    picture: &T,
    refresh_frame_flags: u8
) -> Result<()>

fn block_on_one(&mut self) -> Result<()>

fn get_ready_frames(&mut self) -> Vec<T>

Returns the ready handles.

fn handle_frame(&mut self, frame: &Frame<&[u8]>, timestamp: u64) -> Result<T>

Handle a single frame.

fn negotiation_possible(&self, frame: &Frame<impl AsRef<[u8]>>) -> bool

fn clamp<U: PartialOrd>(x: U, low: U, high: U) -> U

A clamp such that min <= x <= max

fn seg_feature_active(hdr: &Header, segment_id: u8, feature: u8) -> bool

An implementation of seg_feature_active as per “6.4.9 Segmentation feature active syntax”

fn get_qindex(hdr: &Header, segment_id: u8) -> i32

An implementation of get_qindex as per “8.6.1 Dequantization functions”

fn get_dc_quant(hdr: &Header, segment_id: u8, luma: bool) -> Result<i32>

An implementation of get_dc_quant as per “8.6.1 Dequantization functions”

fn get_ac_quant(hdr: &Header, segment_id: u8, luma: bool) -> Result<i32>

An implementation of get_ac_quant as per “8.6.1 Dequantization functions”

fn update_segmentation(
    hdr: &Header,
    segmentation: &mut [Segmentation; 8]
) -> Result<()>

Update the state of the segmentation parameters after seeing a frame

Trait Implementations

impl<T: DecodedHandle + DynDecodedHandle + 'static> VideoDecoder for Decoder<T>

fn decode(
    &mut self,
    timestamp: u64,
    bitstream: &[u8]
) -> VideoDecoderResult<Vec<Box<dyn DynDecodedHandle>>>

Decode the bitstream represented by timestamp. Returns zero or more decoded handles representing the decoded data.

fn flush(&mut self) -> VideoDecoderResult<Vec<Box<dyn DynDecodedHandle>>>

Flush the decoder i.e. finish processing all queued decode requests and emit frames for them.

fn negotiation_possible(&self) -> bool

Whether negotiation of the decoded format is possible. In particular, a decoder will indicate that negotiation is possible after enough metadata is collected from parsing the bitstream through calls to the decode() method.

fn num_resources_left(&self) -> Option<usize>

Gets the number of output resources left in the backend after accounting for any buffers that might be queued in the decoder.

fn num_resources_total(&self) -> usize

Gets the number of output resources allocated by the backend.

fn coded_resolution(&self) -> Option<Resolution>

Returns the current coded resolution of the bitstream being processed. This may be None if we have not read the stream parameters yet.

fn poll(
    &mut self,
    blocking_mode: BlockingMode
) -> VideoDecoderResult<Vec<Box<dyn DynDecodedHandle>>>

Polls the decoder, emitting frames for all queued decode requests. This is similar to flush, but it does not change the state of the decoded picture buffer nor does it reset any internal state.