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subtitle

Subtitle stream utilities.

Classes:

Name Description
SubtitleStream

A stream that contains subtitle data.

SubtitleStream dataclass

SubtitleStream(
    *,
    node: FilterNode | InputNode,
    index: int | None = None,
    optional: bool = False
)

Bases: FilterableStream

A stream that contains subtitle data.

Methods:

Name Description
afilter

Apply a custom audio filter to this stream.

filter_multi_output

Apply a custom filter with multiple outputs to this stream.

output

Output file URL.

vfilter

Apply a custom video filter to this stream.

view

Visualize the stream.

Attributes:

Name Type Description
hex str

Get the hexadecimal hash of the object.

index int | None

Represents the index of the stream in the node's output streams.

node FilterNode | InputNode

Represents the node that the stream is connected to in the upstream direction.

optional bool

Represents whether the stream is optional.

hex cached property

hex: str

Get the hexadecimal hash of the object.

index class-attribute instance-attribute

index: int | None = None

Represents the index of the stream in the node's output streams.

Note

See Also: Stream specifiers stream_index

node instance-attribute

Represents the node that the stream is connected to in the upstream direction.

Note

In the context of a data stream, the 'upstream' refers to the source of the data, or where the data is coming from. Therefore, the 'upstream node' is the node that is providing the data to the current stream.

optional class-attribute instance-attribute

optional: bool = False

Represents whether the stream is optional.

Note

See Also: Advanced options

afilter

afilter(
    *streams: FilterableStream,
    name: str,
    input_typings: tuple[StreamType, ...] = (audio,),
    **kwargs: Any
) -> AudioStream

Apply a custom audio filter to this stream.

This method applies a custom FFmpeg audio filter to this stream and returns the resulting audio stream. It's a convenience wrapper around filter_multi_output that handles the case of filters with a single audio output.

Parameters:

Name Type Description Default
*streams FilterableStream

Additional input streams for the filter

()
name str

The name of the FFmpeg filter to apply

required
input_typings tuple[StreamType, ...]

The expected types of the input streams (defaults to all audio)

(audio,)
**kwargs Any

Filter-specific parameters as keyword arguments

{}

Returns:

Type Description
AudioStream

An AudioStream representing the filter's output

Example
# Apply a volume filter to an audio stream
louder = stream.afilter(name="volume", volume=2.0)

filter_multi_output

filter_multi_output(
    *streams: FilterableStream,
    name: str,
    input_typings: tuple[StreamType, ...] = (),
    output_typings: tuple[StreamType, ...] = (),
    **kwargs: Any
) -> FilterNode

Apply a custom filter with multiple outputs to this stream.

This method creates a FilterNode that applies a custom FFmpeg filter to this stream (and optionally additional streams). Unlike vfilter and afilter which return a single stream, this method returns the FilterNode itself, allowing access to multiple output streams.

Parameters:

Name Type Description Default
*streams FilterableStream

Additional input streams for the filter

()
name str

The name of the FFmpeg filter to apply

required
input_typings tuple[StreamType, ...]

The expected types of the input streams

()
output_typings tuple[StreamType, ...]

The types of output streams this filter produces

()
**kwargs Any

Filter-specific parameters as keyword arguments

{}

Returns:

Type Description
FilterNode

A FilterNode that can be used to access the filter's outputs

Example
# Split a video into two identical streams
split_node = stream.filter_multi_output(
    name="split", output_typings=(StreamType.video, StreamType.video)
)
stream1 = split_node.video(0)
stream2 = split_node.video(1)

output

output(
    *streams: FilterableStream,
    filename: str | Path,
    f: String = None,
    c: String = None,
    codec: String = None,
    pre: String = None,
    map: Func = None,
    map_metadata: String = None,
    map_chapters: Int = None,
    t: Time = None,
    to: Time = None,
    fs: Int64 = None,
    ss: Time = None,
    timestamp: Func = None,
    metadata: String = None,
    program: String = None,
    stream_group: String = None,
    dframes: Int64 = None,
    target: Func = None,
    shortest: Boolean = None,
    shortest_buf_duration: Float = None,
    bitexact: Boolean = None,
    apad: String = None,
    copyinkf: Boolean = None,
    copypriorss: Int = None,
    frames: Int64 = None,
    tag: String = None,
    q: Func = None,
    qscale: Func = None,
    profile: Func = None,
    filter: String = None,
    filter_script: String = None,
    attach: Func = None,
    disposition: String = None,
    thread_queue_size: Int = None,
    bits_per_raw_sample: Int = None,
    stats_enc_pre: String = None,
    stats_enc_post: String = None,
    stats_mux_pre: String = None,
    stats_enc_pre_fmt: String = None,
    stats_enc_post_fmt: String = None,
    stats_mux_pre_fmt: String = None,
    vframes: Int64 = None,
    r: String = None,
    fpsmax: String = None,
    s: String = None,
    aspect: String = None,
    pix_fmt: String = None,
    vn: Boolean = None,
    rc_override: String = None,
    vcodec: String = None,
    timecode: Func = None,
    _pass: Int = None,
    passlogfile: String = None,
    vf: String = None,
    intra_matrix: String = None,
    inter_matrix: String = None,
    chroma_intra_matrix: String = None,
    vtag: String = None,
    fps_mode: String = None,
    force_fps: Boolean = None,
    streamid: Func = None,
    force_key_frames: String = None,
    b: Func = None,
    autoscale: Boolean = None,
    fix_sub_duration_heartbeat: Boolean = None,
    aframes: Int64 = None,
    aq: Func = None,
    ar: Int = None,
    ac: Int = None,
    an: Boolean = None,
    acodec: String = None,
    ab: Func = None,
    atag: String = None,
    sample_fmt: String = None,
    channel_layout: String = None,
    ch_layout: String = None,
    af: String = None,
    sn: Boolean = None,
    scodec: String = None,
    stag: String = None,
    muxdelay: Float = None,
    muxpreload: Float = None,
    sdp_file: Func = None,
    time_base: String = None,
    enc_time_base: String = None,
    bsf: String = None,
    apre: String = None,
    vpre: String = None,
    spre: String = None,
    fpre: String = None,
    max_muxing_queue_size: Int = None,
    muxing_queue_data_threshold: Int = None,
    dcodec: String = None,
    dn: Boolean = None,
    top: Int = None,
    encoder_options: FFMpegEncoderOption | None = None,
    muxer_options: FFMpegMuxerOption | None = None,
    format_options: (
        FFMpegAVFormatContextEncoderOption | None
    ) = None,
    codec_options: (
        FFMpegAVCodecContextEncoderOption | None
    ) = None,
    extra_options: dict[str, Any] | None = None
) -> OutputStream

Output file URL.

Parameters:

Name Type Description Default
*streams FilterableStream

the streams to output

()
filename str | Path

the filename to output to

required
f String

force container format (auto-detected otherwise)

None
c String

select encoder/decoder ('copy' to copy stream without reencoding)

None
codec String

alias for -c (select encoder/decoder)

None
pre String

preset name

None
map Func

set input stream mapping

None
map_metadata String

set metadata information of outfile from infile

None
map_chapters Int

set chapters mapping

None
t Time

stop transcoding after specified duration

None
to Time

stop transcoding after specified time is reached

None
fs Int64

set the limit file size in bytes

None
ss Time

start transcoding at specified time

None
timestamp Func

set the recording timestamp ('now' to set the current time)

None
metadata String

add metadata

None
program String

add program with specified streams

None
stream_group String

add stream group with specified streams and group type-specific arguments

None
dframes Int64

set the number of data frames to output

None
target Func

specify target file type (\"vcd\", \"svcd\", \"dvd\", \"dv\" or \"dv50\" with optional prefixes \"pal-\", \"ntsc-\" or \"film-\")

None
shortest Boolean

finish encoding within shortest input

None
shortest_buf_duration Float

maximum buffering duration (in seconds) for the -shortest option

None
bitexact Boolean

bitexact mode

None
apad String

audio pad

None
copyinkf Boolean

copy initial non-keyframes

None
copypriorss Int

copy or discard frames before start time

None
frames Int64

set the number of frames to output

None
tag String

force codec tag/fourcc

None
q Func

use fixed quality scale (VBR)

None
qscale Func

use fixed quality scale (VBR)

None
profile Func

set profile

None
filter String

apply specified filters to audio/video

None
filter_script String

deprecated, use -/filter

None
attach Func

add an attachment to the output file

None
disposition String

disposition

None
thread_queue_size Int

set the maximum number of queued packets from the demuxer

None
bits_per_raw_sample Int

set the number of bits per raw sample

None
stats_enc_pre String

write encoding stats before encoding

None
stats_enc_post String

write encoding stats after encoding

None
stats_mux_pre String

write packets stats before muxing

None
stats_enc_pre_fmt String

format of the stats written with -stats_enc_pre

None
stats_enc_post_fmt String

format of the stats written with -stats_enc_post

None
stats_mux_pre_fmt String

format of the stats written with -stats_mux_pre

None
vframes Int64

set the number of video frames to output

None
r String

override input framerate/convert to given output framerate (Hz value, fraction or abbreviation)

None
fpsmax String

set max frame rate (Hz value, fraction or abbreviation)

None
s String

set frame size (WxH or abbreviation)

None
aspect String

set aspect ratio (4:3, 16:9 or 1.3333, 1.7777)

None
pix_fmt String

set pixel format

None
vn Boolean

disable video

None
rc_override String

rate control override for specific intervals

None
vcodec String

alias for -c:v (select encoder/decoder for video streams)

None
timecode Func

set initial TimeCode value.

None
_pass Int

select the pass number (1 to 3)

None
passlogfile String

select two pass log file name prefix

None
vf String

alias for -filter:v (apply filters to video streams)

None
intra_matrix String

specify intra matrix coeffs

None
inter_matrix String

specify inter matrix coeffs

None
chroma_intra_matrix String

specify intra matrix coeffs

None
vtag String

force video tag/fourcc

None
fps_mode String

set framerate mode for matching video streams; overrides vsync

None
force_fps Boolean

force the selected framerate, disable the best supported framerate selection

None
streamid Func

set the value of an outfile streamid

None
force_key_frames String

force key frames at specified timestamps

None
b Func

video bitrate (please use -b:v)

None
autoscale Boolean

automatically insert a scale filter at the end of the filter graph

None
fix_sub_duration_heartbeat Boolean

set this video output stream to be a heartbeat stream for fix_sub_duration, according to which subtitles should be split at random access points

None
aframes Int64

set the number of audio frames to output

None
aq Func

set audio quality (codec-specific)

None
ar Int

set audio sampling rate (in Hz)

None
ac Int

set number of audio channels

None
an Boolean

disable audio

None
acodec String

alias for -c:a (select encoder/decoder for audio streams)

None
ab Func

alias for -b:a (select bitrate for audio streams)

None
atag String

force audio tag/fourcc

None
sample_fmt String

set sample format

None
channel_layout String

set channel layout

None
ch_layout String

set channel layout

None
af String

alias for -filter:a (apply filters to audio streams)

None
sn Boolean

disable subtitle

None
scodec String

alias for -c:s (select encoder/decoder for subtitle streams)

None
stag String

force subtitle tag/fourcc

None
muxdelay Float

set the maximum demux-decode delay

None
muxpreload Float

set the initial demux-decode delay

None
sdp_file Func

specify a file in which to print sdp information

None
time_base String

set the desired time base hint for output stream (1:24, 1:48000 or 0.04166, 2.0833e-5)

None
enc_time_base String

set the desired time base for the encoder (1:24, 1:48000 or 0.04166, 2.0833e-5). two special values are defined - 0 = use frame rate (video) or sample rate (audio),-1 = match source time base

None
bsf String

A comma-separated list of bitstream filters

None
apre String

set the audio options to the indicated preset

None
vpre String

set the video options to the indicated preset

None
spre String

set the subtitle options to the indicated preset

None
fpre String

set options from indicated preset file

None
max_muxing_queue_size Int

maximum number of packets that can be buffered while waiting for all streams to initialize

None
muxing_queue_data_threshold Int

set the threshold after which max_muxing_queue_size is taken into account

None
dcodec String

alias for -c:d (select encoder/decoder for data streams)

None
dn Boolean

disable data

None
top Int

deprecated, use the setfield video filter

None
encoder_options FFMpegEncoderOption | None

ffmpeg's encoder options

None
muxer_options FFMpegMuxerOption | None

FFMpegMuxerOption

None
format_options FFMpegAVFormatContextEncoderOption | None

FFMpegAVFormatContextEncoderOption

None
codec_options FFMpegAVCodecContextEncoderOption | None

FFMpegAVCodecContextEncoderOption

None
extra_options dict[str, Any] | None

the arguments for the output

None

Returns:

Type Description
OutputStream

the output stream

vfilter

vfilter(
    *streams: FilterableStream,
    name: str,
    input_typings: tuple[StreamType, ...] = (video,),
    **kwargs: Any
) -> VideoStream

Apply a custom video filter to this stream.

This method applies a custom FFmpeg video filter to this stream and returns the resulting video stream. It's a convenience wrapper around filter_multi_output that handles the case of filters with a single video output.

Parameters:

Name Type Description Default
*streams FilterableStream

Additional input streams for the filter

()
name str

The name of the FFmpeg filter to apply

required
input_typings tuple[StreamType, ...]

The expected types of the input streams (defaults to all video)

(video,)
**kwargs Any

Filter-specific parameters as keyword arguments

{}

Returns:

Type Description
VideoStream

A VideoStream representing the filter's output

Example
# Apply a blur filter to a video stream
blurred = stream.vfilter(name="boxblur", luma_radius=2)

view

view(format: Literal['png', 'svg', 'dot'] = 'png') -> str

Visualize the stream.

Parameters:

Name Type Description Default
format Literal['png', 'svg', 'dot']

The format of the view.

'png'

Returns:

Type Description
str

The file path of the visualization.