Struct Timestamp

Source

pub struct Timestamp { /* private fields */ }

Expand description

A timestamp representing a point in time within a media stream.

Timestamps are represented as a presentation timestamp (PTS) value combined with a time base that defines the unit of measurement.

§Time Base

The time base is a rational number that represents the duration of one timestamp unit. For example:

1/90000: Each PTS unit is 1/90000 of a second (MPEG-TS)
1/1000: Each PTS unit is 1 millisecond
1/48000: Each PTS unit is one audio sample at 48kHz

§Examples

use ff_format::{Rational, Timestamp};
use std::time::Duration;

// Create a timestamp at 1 second using 90kHz time base
let time_base = Rational::new(1, 90000);
let ts = Timestamp::new(90000, time_base);

assert!((ts.as_secs_f64() - 1.0).abs() < 0.0001);
assert_eq!(ts.as_millis(), 1000);

// Convert from Duration
let ts2 = Timestamp::from_duration(Duration::from_secs(1), time_base);
assert_eq!(ts2.pts(), 90000);

Implementations§

Source §

impl Timestamp

Source

pub const fn new(pts: i64, time_base: Rational) -> Timestamp

Creates a new timestamp with the given PTS value and time base.

§Arguments

pts - The presentation timestamp value
time_base - The time base (duration of one PTS unit)

§Examples

use ff_format::{Rational, Timestamp};

let time_base = Rational::new(1, 1000);  // milliseconds
let ts = Timestamp::new(500, time_base);  // 500ms
assert_eq!(ts.as_millis(), 500);

Source

pub const fn zero(time_base: Rational) -> Timestamp

Creates a timestamp representing zero (0 PTS).

§Examples

use ff_format::{Rational, Timestamp};

let time_base = Rational::new(1, 90000);
let zero = Timestamp::zero(time_base);
assert_eq!(zero.pts(), 0);
assert_eq!(zero.as_secs_f64(), 0.0);

Source

pub fn from_duration(duration: Duration, time_base: Rational) -> Timestamp

Creates a timestamp from a Duration value.

§Arguments

duration - The duration to convert
time_base - The target time base for the resulting timestamp

§Examples

use ff_format::{Rational, Timestamp};
use std::time::Duration;

let time_base = Rational::new(1, 90000);
let ts = Timestamp::from_duration(Duration::from_millis(1000), time_base);
assert_eq!(ts.pts(), 90000);

Source

pub fn from_secs_f64(secs: f64, time_base: Rational) -> Timestamp

Creates a timestamp from a seconds value.

§Examples

use ff_format::{Rational, Timestamp};

let time_base = Rational::new(1, 1000);
let ts = Timestamp::from_secs_f64(1.5, time_base);
assert_eq!(ts.pts(), 1500);

Source

pub fn from_millis(millis: i64, time_base: Rational) -> Timestamp

Creates a timestamp from milliseconds.

§Examples

use ff_format::{Rational, Timestamp};

let time_base = Rational::new(1, 90000);
let ts = Timestamp::from_millis(1000, time_base);
assert_eq!(ts.pts(), 90000);

Source

pub const fn pts(&self) -> i64

Returns the presentation timestamp value.

§Examples

use ff_format::{Rational, Timestamp};

let ts = Timestamp::new(12345, Rational::new(1, 90000));
assert_eq!(ts.pts(), 12345);

Source

pub const fn time_base(&self) -> Rational

Returns the time base.

§Examples

use ff_format::{Rational, Timestamp};

let time_base = Rational::new(1, 90000);
let ts = Timestamp::new(100, time_base);
assert_eq!(ts.time_base(), time_base);

Source

pub fn as_duration(&self) -> Duration

Converts the timestamp to a Duration.

Note: Negative timestamps will be clamped to zero Duration.

§Examples

use ff_format::{Rational, Timestamp};
use std::time::Duration;

let ts = Timestamp::new(90000, Rational::new(1, 90000));
let duration = ts.as_duration();
assert_eq!(duration, Duration::from_secs(1));

Source

pub fn as_secs_f64(&self) -> f64

Converts the timestamp to seconds as a floating-point value.

§Examples

use ff_format::{Rational, Timestamp};

let ts = Timestamp::new(45000, Rational::new(1, 90000));
assert!((ts.as_secs_f64() - 0.5).abs() < 0.0001);

Source

pub fn as_millis(&self) -> i64

Converts the timestamp to milliseconds.

§Examples

use ff_format::{Rational, Timestamp};

let ts = Timestamp::new(90000, Rational::new(1, 90000));
assert_eq!(ts.as_millis(), 1000);

Source

pub fn as_micros(&self) -> i64

Converts the timestamp to microseconds.

§Examples

use ff_format::{Rational, Timestamp};

let ts = Timestamp::new(90, Rational::new(1, 90000));
assert_eq!(ts.as_micros(), 1000);  // 90/90000 = 0.001 sec = 1000 microseconds

Source

pub fn as_frame_number(&self, fps: f64) -> u64

Converts the timestamp to a frame number at the given frame rate.

§Arguments

fps - The frame rate (frames per second)

§Examples

use ff_format::{Rational, Timestamp};

let ts = Timestamp::new(90000, Rational::new(1, 90000));  // 1 second
assert_eq!(ts.as_frame_number(30.0), 30);  // 30 fps
assert_eq!(ts.as_frame_number(60.0), 60);  // 60 fps

Source

pub fn as_frame_number_rational(&self, fps: Rational) -> u64

Converts the timestamp to a frame number using a rational frame rate.

§Arguments

fps - The frame rate as a rational number

§Examples

use ff_format::{Rational, Timestamp};

let ts = Timestamp::new(90000, Rational::new(1, 90000));  // 1 second
let fps = Rational::new(30000, 1001);  // 29.97 fps
let frame = ts.as_frame_number_rational(fps);
assert!(frame == 29 || frame == 30);  // Should be approximately 30

Source

pub fn rescale(&self, new_time_base: Rational) -> Timestamp

Rescales this timestamp to a different time base.

§Arguments

new_time_base - The target time base

§Examples

use ff_format::{Rational, Timestamp};

let ts = Timestamp::new(1000, Rational::new(1, 1000));  // 1 second
let rescaled = ts.rescale(Rational::new(1, 90000));
assert_eq!(rescaled.pts(), 90000);

Source

pub const fn is_zero(&self) -> bool

Returns true if this timestamp is zero.

§Examples

use ff_format::{Rational, Timestamp};

let zero = Timestamp::zero(Rational::new(1, 90000));
assert!(zero.is_zero());

let non_zero = Timestamp::new(100, Rational::new(1, 90000));
assert!(!non_zero.is_zero());

Source

pub const fn is_negative(&self) -> bool

Returns true if this timestamp is negative.

§Examples

use ff_format::{Rational, Timestamp};

let negative = Timestamp::new(-100, Rational::new(1, 90000));
assert!(negative.is_negative());

Source

pub const fn invalid() -> Timestamp

Returns a sentinel Timestamp representing “no PTS available”.

This mirrors FFmpeg’s AV_NOPTS_VALUE (INT64_MIN). Use is_valid to check before calling any conversion method.

§Examples

use ff_format::Timestamp;

let ts = Timestamp::invalid();
assert!(!ts.is_valid());

Source

pub const fn is_valid(&self) -> bool

Returns true if this timestamp represents a real PTS value.

Returns false when the timestamp was constructed via invalid, which corresponds to FFmpeg’s AV_NOPTS_VALUE.

§Examples

use ff_format::{Timestamp, Rational};

let valid = Timestamp::new(1000, Rational::new(1, 48000));
assert!(valid.is_valid());

let invalid = Timestamp::invalid();
assert!(!invalid.is_valid());