Struct devices::virtio::video::decoder::backend::vaapi::VaapiDecoderSession

pub struct VaapiDecoderSession {
    codec: Box<dyn StatelessVideoDecoder<BufferDescWithPicId>>,
    output_queue_state: OutputQueueState,
    held_frames: BTreeMap<i32, BorrowedFrame>,
    submit_queue: VecDeque<PendingJob>,
    event_queue: EventQueue<DecoderEvent>,
    flushing: bool,
}

A decoder session for the libva backend

Fields

codec: Box<dyn StatelessVideoDecoder<BufferDescWithPicId>>

The implementation for the codec specific logic.

output_queue_state: OutputQueueState

The state for the output queue. Updated when set_output_buffer_count is called or when we detect a dynamic resolution change.

held_frames: BTreeMap<i32, BorrowedFrame>

Frames currently held by us, indexed by picture_buffer_id.

submit_queue: VecDeque<PendingJob>

Queue containing the buffers we have not yet submitted to the codec.

event_queue: EventQueue<DecoderEvent>

The event queue we can use to signal new events.

flushing: bool

Whether the decoder is currently flushing.

Implementations

impl VaapiDecoderSession

fn output_picture( decoded_frame: &dyn DecodedHandle<Descriptor = BufferDescWithPicId>, event_queue: &mut EventQueue<DecoderEvent> ) -> Result<()>

Copy raw decoded data from image into the output buffer

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

fn drain_submit_queue(&mut self) -> Result<(), VideoError>

fn process_decoder_events(&mut self) -> Result<(), VideoError>

fn try_make_progress(&mut self) -> Result<(), VideoError>

Trait Implementations

impl DecoderSession for VaapiDecoderSession

fn set_output_parameters( &mut self, _: usize, _: Format ) -> Result<(), VideoError>

Tell how many output buffers will be used for this session and which format they will carry. This method must be called after a ProvidePictureBuffers event is emitted, and before the first call to use_output_buffer().

fn decode( &mut self, resource_id: u32, timestamp: u64, resource: GuestResourceHandle, offset: u32, bytes_used: u32 ) -> Result<(), VideoError>

Decode the compressed stream contained in [offset..offset+bytes_used] of the shared memory in the input resource.

fn flush(&mut self) -> Result<(), VideoError>

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

fn reset(&mut self) -> Result<(), VideoError>

Reset the decoder device, i.e. cancel all pending decoding requests.

fn clear_output_buffers(&mut self) -> Result<(), VideoError>

Immediately release all buffers passed using use_output_buffer() and reuse_output_buffer().

fn event_pipe(&self) -> &dyn AsRawDescriptor

Returns the event pipe on which the availability of events will be signaled. Note that the returned value is borrowed and only valid as long as the session is alive.

fn use_output_buffer( &mut self, picture_buffer_id: i32, resource: GuestResource ) -> Result<(), VideoError>

Ask the device to use resource to store decoded frames according to its layout. picture_buffer_id is the ID of the picture that will be reproduced in PictureReady events using this buffer.

fn reuse_output_buffer( &mut self, picture_buffer_id: i32 ) -> Result<(), VideoError>

Ask the device to reuse an output buffer previously passed to use_output_buffer and that has previously been returned to the decoder in a PictureReady event.

fn read_event(&mut self) -> Result<DecoderEvent, VideoError>

Blocking call to read a single event from the event pipe.