Struct gstreamer::SeekFlags

pub struct SeekFlags { /* fields omitted */ }

Flags to be used with [crate::Element::seek()] or [crate::Event::new_seek()]. All flags can be used together.

A non flushing seek might take some time to perform as the currently playing data in the pipeline will not be cleared.

An accurate seek might be slower for formats that don’t have any indexes or timestamp markers in the stream. Specifying this flag might require a complete scan of the file in those cases.

When performing a segment seek: after the playback of the segment completes, no EOS will be emitted by the element that performed the seek, but a crate::MessageType::SegmentDone message will be posted on the bus by the element. When this message is posted, it is possible to send a new seek event to continue playback. With this seek method it is possible to perform seamless looping or simple linear editing.

When only changing the playback rate and not the direction, the [Self::InstantRateChange] flag can be used for a non-flushing seek to signal that the rate change should be applied immediately. This requires special support in the seek handlers (e.g. demuxers) and any elements synchronizing to the clock, and in general can’t work in all cases (for example UDP streaming where the delivery rate is controlled by a remote server). The instant-rate-change mode supports changing the trickmode-related GST_SEEK_ flags, but can’t be used in conjunction with other seek flags that affect the new playback position - as the playback position will not be changing.

When doing fast forward (rate > 1.0) or fast reverse (rate < -1.0) trickmode playback, the [Self::Trickmode] flag can be used to instruct decoders and demuxers to adjust the playback rate by skipping frames. This can improve performance and decrease CPU usage because not all frames need to be decoded.

Beyond that, the [Self::TrickmodeKeyUnits] flag can be used to request that decoders skip all frames except key units, and [Self::TrickmodeNoAudio] flags can be used to request that audio decoders do no decoding at all, and simple output silence.

The [Self::SnapBefore] flag can be used to snap to the previous relevant location, and the [Self::SnapAfter] flag can be used to select the next relevant location. If [Self::KeyUnit] is specified, the relevant location is a keyframe. If both flags are specified, the nearest of these locations will be selected. If none are specified, the implementation is free to select whichever it wants.

The before and after here are in running time, so when playing backwards, the next location refers to the one that will played in next, and not the one that is located after in the actual source stream.

Also see part-seeking.txt in the GStreamer design documentation for more details on the meaning of these flags and the behaviour expected of elements that handle them.

Implementations

impl SeekFlags

pub const FLUSH: SeekFlags

flush pipeline

pub const ACCURATE: SeekFlags

accurate position is requested, this might be considerably slower for some formats.

pub const KEY_UNIT: SeekFlags

seek to the nearest keyframe. This might be faster but less accurate.

pub const SEGMENT: SeekFlags

perform a segment seek.

pub const TRICKMODE: SeekFlags

when doing fast forward or fast reverse playback, allow elements to skip frames instead of generating all frames. (Since: 1.6)

pub const SKIP: SeekFlags

Deprecated backward compatibility flag, replaced by [Self::Trickmode]

pub const SNAP_BEFORE: SeekFlags

go to a location before the requested position, if [Self::KeyUnit] this means the keyframe at or before the requested position the one at or before the seek target.

pub const SNAP_AFTER: SeekFlags

go to a location after the requested position, if [Self::KeyUnit] this means the keyframe at of after the requested position.

pub const SNAP_NEAREST: SeekFlags

go to a position near the requested position, if [Self::KeyUnit] this means the keyframe closest to the requested position, if both keyframes are at an equal distance, behaves like [Self::SnapBefore].

pub const TRICKMODE_KEY_UNITS: SeekFlags

when doing fast forward or fast reverse playback, request that elements only decode keyframes and skip all other content, for formats that have keyframes. (Since: 1.6)

pub const TRICKMODE_NO_AUDIO: SeekFlags

when doing fast forward or fast reverse playback, request that audio decoder elements skip decoding and output only gap events or silence. (Since: 1.6)

pub const TRICKMODE_FORWARD_PREDICTED: SeekFlags

This is supported on crate feature v1_18 only.

When doing fast forward or fast reverse playback, request that elements only decode keyframes and forward predicted frames and skip all other content (for example B-Frames), for formats that have keyframes and forward predicted frames. (Since: 1.18)

pub const INSTANT_RATE_CHANGE: SeekFlags

This is supported on crate feature v1_18 only.

Signals that a rate change should be applied immediately. Only valid if start/stop position are GST_CLOCK_TIME_NONE, the playback direction does not change and the seek is not flushing. (Since: 1.18)

pub const fn empty() -> SeekFlags

Returns an empty set of flags

pub const fn all() -> SeekFlags

Returns the set containing all flags.

pub const fn bits(&self) -> u32

Returns the raw value of the flags currently stored.

pub fn from_bits(bits: u32) -> Option<SeekFlags>

Convert from underlying bit representation, unless that representation contains bits that do not correspond to a flag.

pub const fn from_bits_truncate(bits: u32) -> SeekFlags

Convert from underlying bit representation, dropping any bits that do not correspond to flags.

pub const unsafe fn from_bits_unchecked(bits: u32) -> SeekFlags

Convert from underlying bit representation, preserving all bits (even those not corresponding to a defined flag).

pub const fn is_empty(&self) -> bool

Returns true if no flags are currently stored.

pub const fn is_all(&self) -> bool

Returns true if all flags are currently set.

pub const fn intersects(&self, other: SeekFlags) -> bool

Returns true if there are flags common to both self and other.

pub const fn contains(&self, other: SeekFlags) -> bool

Returns true all of the flags in other are contained within self.

pub fn insert(&mut self, other: SeekFlags)

Inserts the specified flags in-place.

pub fn remove(&mut self, other: SeekFlags)

Removes the specified flags in-place.

pub fn toggle(&mut self, other: SeekFlags)

Toggles the specified flags in-place.

pub fn set(&mut self, other: SeekFlags, value: bool)

Inserts or removes the specified flags depending on the passed value.

Trait Implementations

impl Binary for SeekFlags

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

Formats the value using the given formatter.

impl BitAnd<SeekFlags> for SeekFlags

fn bitand(self, other: SeekFlags) -> SeekFlags

Returns the intersection between the two sets of flags.

type Output = SeekFlags

The resulting type after applying the & operator.

impl BitAndAssign<SeekFlags> for SeekFlags

fn bitand_assign(&mut self, other: SeekFlags)

Disables all flags disabled in the set.

impl BitOr<SeekFlags> for SeekFlags

fn bitor(self, other: SeekFlags) -> SeekFlags

Returns the union of the two sets of flags.

type Output = SeekFlags

The resulting type after applying the | operator.

impl BitOrAssign<SeekFlags> for SeekFlags

fn bitor_assign(&mut self, other: SeekFlags)

Adds the set of flags.

impl BitXor<SeekFlags> for SeekFlags

fn bitxor(self, other: SeekFlags) -> SeekFlags

Returns the left flags, but with all the right flags toggled.

type Output = SeekFlags

The resulting type after applying the ^ operator.

impl BitXorAssign<SeekFlags> for SeekFlags

fn bitxor_assign(&mut self, other: SeekFlags)

Toggles the set of flags.

impl Clone for SeekFlags

fn clone(&self) -> SeekFlags

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for SeekFlags

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

Formats the value using the given formatter.

impl Extend<SeekFlags> for SeekFlags

fn extend<T: IntoIterator<Item = SeekFlags>>(&mut self, iterator: T)

Extends a collection with the contents of an iterator.

fn extend_one(&mut self, item: A)

🔬 This is a nightly-only experimental API. (extend_one)

Extends a collection with exactly one element.

fn extend_reserve(&mut self, additional: usize)

🔬 This is a nightly-only experimental API. (extend_one)

Reserves capacity in a collection for the given number of additional elements.

impl FromIterator<SeekFlags> for SeekFlags

fn from_iter<T: IntoIterator<Item = SeekFlags>>(iterator: T) -> SeekFlags

Creates a value from an iterator.

impl<'a> FromValue<'a> for SeekFlags

type Checker = GenericValueTypeChecker<Self>

Value type checker.

unsafe fn from_value(value: &'a Value) -> Self

Get the contained value from a Value.

impl Hash for SeekFlags

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given Hasher.

impl LowerHex for SeekFlags

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

Formats the value using the given formatter.

impl Not for SeekFlags

fn not(self) -> SeekFlags

Returns the complement of this set of flags.

type Output = SeekFlags

The resulting type after applying the ! operator.

impl Octal for SeekFlags

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

Formats the value using the given formatter.

impl Ord for SeekFlags

fn cmp(&self, other: &SeekFlags) -> Ordering

This method returns an Ordering between self and other.

#[must_use]

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

#[must_use]

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

#[must_use]

fn clamp(self, min: Self, max: Self) -> Self

Restrict a value to a certain interval.

impl PartialEq<SeekFlags> for SeekFlags

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

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=.

impl PartialOrd<SeekFlags> for SeekFlags

fn partial_cmp(&self, other: &SeekFlags) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

#[must_use]

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

This method tests less than (for self and other) and is used by the < operator.

#[must_use]

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

This method tests less than or equal to (for self and other) and is used by the <= operator.

#[must_use]

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

This method tests greater than (for self and other) and is used by the > operator.

#[must_use]

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

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl StaticType for SeekFlags

fn static_type() -> Type

Returns the type identifier of Self.

impl Sub<SeekFlags> for SeekFlags

fn sub(self, other: SeekFlags) -> SeekFlags

Returns the set difference of the two sets of flags.

type Output = SeekFlags

The resulting type after applying the - operator.

impl SubAssign<SeekFlags> for SeekFlags

fn sub_assign(&mut self, other: SeekFlags)

Disables all flags enabled in the set.

impl ToValue for SeekFlags

fn to_value(&self) -> Value

Convert a value to a Value.

fn value_type(&self) -> Type

Returns the type identifer of self.

impl UpperHex for SeekFlags

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

Formats the value using the given formatter.

impl ValueType for SeekFlags

type Type = Self

Type to get the Type from.

impl Copy for SeekFlags

impl Eq for SeekFlags

impl StructuralEq for SeekFlags

impl StructuralPartialEq for SeekFlags