Struct DetailedCodecDescription 

pub struct DetailedCodecDescription {
    pub codec_type: Option<CodecType>,
    pub mime_type: Option<String>,
    pub is_hw: Option<bool>,
    pub profile_descriptions: Option<ProfileDescriptions>,
    pub supports_dynamic_buffers: Option<bool>,
    pub dynamic_buffers_input_max: Option<u32>,
    pub dynamic_buffers_output_max: Option<u32>,
    pub dynamic_buffers_video_decoder_output_safe: Option<u32>,
    pub codec_specifier: Option<String>,
    /* private fields */
}

Clients needing codec information prior to just requesting a codec with CodecFactory.CreateDecoder or CodecFactory.CreateEncoder should use GetDetailedCodecDescriptions to get this table, which has details re. the codec and the profile entries supported by the codec.

Clients with no real need for codec information prior to requesting a codec can simply use CodecFactory.CreateDecoder or CodecFactory.CreateEncoder with relevant requirements set in that request, and then call StreamProcessor.Sync (round trip) to see if a codec was created successfully.

Fields

codec_type: Option<CodecType>

Decoder or encoder.

mime_type: Option<String>

The mime type of the compressed format. For decoders this is the mime type of the input. For encoders, this is the mime type of the output.

is_hw: Option<bool>

If this decoder/encoder uses underlying hardware to perform its operations.

profile_descriptions: Option<ProfileDescriptions>

A list of profile descriptions that describe what codec profiles this encoder/decoder supports along with requirements for using each profile.

supports_dynamic_buffers: Option<bool>

If set to true, dynamic buffers are supported by the codec. See also [fuchsia.mediacodec/StreamProcessor.AddBuffer] and [fuchsia.mediacodec/StreamProcessor.RemoveBuffer] which are required to use dynamic buffers.

Regardless of whether AddBuffer and RemoveBuffer are used (vs. SetInputBufferPartialSettings / SetOutputBufferPartialSettings), see [fuchsia.mediacodec/StreamProcessor.EnableOldOutputBuffers] and [fuchsia.mediacodec/StreamProcessor.EnableSameOutputBufferConcurrentlyInFlight] which are only permitted when supports_dynamic_buffers is true. Both of those are required to achieve full bitstream spec compliance with some video bitstream formats such as VP9 (when show_existing_frame is used in unusual ways).

This does not imply support for non-sysmem-provided VMOs.

dynamic_buffers_input_max: Option<u32>

Having more than this many input buffers added and not yet completely removed under the latest buffer_lifetime_ordinal will result in async StreamProcessor channel closure.

dynamic_buffers_output_max: Option<u32>

Having more than this many output buffers added and not yet completely removed under the latest buffer_lifetime_ordinal will result in async StreamProcessor channel closure.

dynamic_buffers_video_decoder_output_safe: Option<u32>

This field is set when a codec both supports dynamic buffers and is a video decoder. Adding this many buffers to a video decoder’s output, and ensuring that the buffers will be usable by the decoder prior to the whole pipeline blocking on lack of availability of usable output buffers in the decoder, will ensure that the decoder doesn’t get stuck waiting for an available output buffer. See also [fuchsia.mediacodec/StreamBufferConstraints.buffer_count_for_server_current] which may occasionally indicate a lower number of output buffers needed, based on headers of the bitstream. However, implementers of clients may wish to first check if the relevant headers in relevant streams are actually set, since this can be rare in practice unfortunately, making paying attention to buffer_count_for_server_current potentially not actually worthwhile, depending on the expected streams’ headers.

codec_specifier: Option<String>

Optionally set [fuchsia.mediacodec/CreateDecoder_Params.codec_specifier] to this string to require an instance of this specific codec. The created codec will still be checked against other requirements specified there for the codec to be created successfully.

This is only valid and specific per boot, not across boots. This allows a discovered codec to be requested without any ambiguity, but is intentionally not a way for clients to hard code which specific codec implementation they want to connect to, as codec selection is by properties / capabilities, not by specific codec implementation.

Trait Implementations

impl Clone for DetailedCodecDescription

fn clone(&self) -> DetailedCodecDescription

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for DetailedCodecDescription

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl<D> Decode<DetailedCodecDescription, D> for DetailedCodecDescription

where D: ResourceDialect,

fn new_empty() -> DetailedCodecDescription

Creates a valid instance of Self. The specific value does not matter, since it will be overwritten by decode.

unsafe fn decode( &mut self, decoder: &mut Decoder<'_, D>, offset: usize, depth: Depth, ) -> Result<(), Error>

Decodes an object of type T from the decoder’s buffers into self.

impl Default for DetailedCodecDescription

fn default() -> DetailedCodecDescription

Returns the “default value” for a type.

impl<D> Encode<DetailedCodecDescription, D> for &DetailedCodecDescription

where D: ResourceDialect,

unsafe fn encode( self, encoder: &mut Encoder<'_, D>, offset: usize, depth: Depth, ) -> Result<(), Error>

Encodes the object into the encoder’s buffers. Any handles stored in the object are swapped for Handle::INVALID.

impl PartialEq for DetailedCodecDescription

fn eq(&self, other: &DetailedCodecDescription) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl TypeMarker for DetailedCodecDescription

type Owned = DetailedCodecDescription

The owned Rust type which this FIDL type decodes into.

fn inline_align(_context: Context) -> usize

Returns the minimum required alignment of the inline portion of the encoded object. It must be a (nonzero) power of two.

fn inline_size(_context: Context) -> usize

Returns the size of the inline portion of the encoded object, including padding for alignment. Must be a multiple of inline_align.

fn encode_is_copy() -> bool

Returns true if the memory layout of Self::Owned matches the FIDL wire format and encoding requires no validation. When true, we can optimize encoding arrays and vectors of Self::Owned to a single memcpy.

fn decode_is_copy() -> bool

Returns true if the memory layout of Self::Owned matches the FIDL wire format and decoding requires no validation. When true, we can optimize decoding arrays and vectors of Self::Owned to a single memcpy.

impl ValueTypeMarker for DetailedCodecDescription

type Borrowed<'a> = &'a DetailedCodecDescription

The Rust type to use for encoding. This is a particular Encode<Self> type cheaply obtainable from &Self::Owned. There are three cases:

fn borrow( value: &<DetailedCodecDescription as TypeMarker>::Owned, ) -> <DetailedCodecDescription as ValueTypeMarker>::Borrowed<'_>

Cheaply converts from &Self::Owned to Self::Borrowed.

impl Persistable for DetailedCodecDescription

impl StructuralPartialEq for DetailedCodecDescription