View Source Membrane.H264.FFmpeg.Parser (Membrane H264 FFmpeg plugin v0.21.1)

Membrane element providing parser for H264 encoded video stream. Uses the parser provided by FFmpeg.

By default, this parser splits the stream into h264 access units, each of which is a sequence of NAL units corresponding to one video frame, and equips them with the following metadata entries under :h264 key:

  • key_frame?: boolean - determines whether the frame is a h264 I frame.

Setting custom packetization options affects metadata, see alignment and attach_nalus? options for details.

element-options

Element options

Passed via struct Membrane.H264.FFmpeg.Parser.t/0

  • framerate

    H264.framerate_t() | nil

    Default value: nil
    Framerate of video stream, see t:Membrane.Caps.Video.H264.framerate_t/0

  • sps

    any

    Default value: ""
    Sequence Parameter Set NAL unit - if absent in the stream, should be provided via this option.

  • pps

    any

    Default value: ""
    Picture Parameter Set NAL unit - if absent in the stream, should be provided via this option.

  • alignment

    :au | :nal

    Default value: :au
    Stream units carried by each output buffer. See t:Membrane.Caps.Video.H264.alignment_t.

    If alignment is :nal, the following metadata entries are added:

    • type - h264 nalu type
    • new_access_unit: access_unit_metadata - added whenever the new access unit starts. access_unit_metadata is the metadata that would be merged into the buffer metadata normally (if alignment was :au).
    • end_access_unit: true - added for each NALu that ends an access unit.
  • attach_nalus?

    boolean

    Default value: false
    Determines whether to attach NAL units list to the metadata when alignment option is set to :au. For details see t:Membrane.Caps.Video.H264.nalu_in_metadata_t/0.

  • skip_until_keyframe?

    boolean

    Default value: false
    Determines whether to drop the stream until the first key frame is received.

  • skip_until_parameters?

    boolean

    Default value: true
    Determines whether to drop the stream until the first set of SPS and PPS is received.

pads

Pads

input

:input

Availability :always
Caps :any
Demand mode :auto
Demand unit :buffers
Direction :input
Mode :pull
Name :input

output

:output

Availability :always
Caps Membrane.H264, restrictions:
  stream_format: :byte_stream
Demand mode :auto
Demand unit :buffers
Direction :output
Mode :pull
Name :output

Link to this section Summary

Types

t()

Struct containing options for Membrane.H264.FFmpeg.Parser

Functions

Returns pads descriptions for Membrane.H264.FFmpeg.Parser

Returns description of options available for this module

Link to this section Types

@type t() :: %Membrane.H264.FFmpeg.Parser{
  alignment: :au | :nal,
  attach_nalus?: boolean(),
  framerate: Membrane.H264.framerate_t() | nil,
  pps: any(),
  skip_until_keyframe?: boolean(),
  skip_until_parameters?: boolean(),
  sps: any()
}

Struct containing options for Membrane.H264.FFmpeg.Parser

Link to this section Functions

@spec membrane_pads() :: [{Membrane.Pad.name_t(), Membrane.Pad.description_t()}]

Returns pads descriptions for Membrane.H264.FFmpeg.Parser

@spec options() :: keyword()

Returns description of options available for this module