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// This file was generated by gir (https://github.com/gtk-rs/gir)
// from gir-files (https://github.com/gtk-rs/gir-files)
// from gst-gir-files (https://gitlab.freedesktop.org/gstreamer/gir-files-rs.git)
// DO NOT EDIT

use crate::VideoCodecFrame;
#[cfg(feature = "v1_20")]
#[cfg_attr(docsrs, doc(cfg(feature = "v1_20")))]
use crate::VideoDecoderRequestSyncPointFlags;
#[cfg(feature = "v1_18")]
#[cfg_attr(docsrs, doc(cfg(feature = "v1_18")))]
use glib::signal::{connect_raw, SignalHandlerId};
use glib::{prelude::*, translate::*};
#[cfg(feature = "v1_18")]
#[cfg_attr(docsrs, doc(cfg(feature = "v1_18")))]
use std::boxed::Box as Box_;

glib::wrapper! {
    /// This base class is for video decoders turning encoded data into raw video
    /// frames.
    ///
    /// The GstVideoDecoder base class and derived subclasses should cooperate as
    /// follows:
    ///
    /// ## Configuration
    ///
    ///  * Initially, GstVideoDecoder calls `start` when the decoder element
    ///  is activated, which allows the subclass to perform any global setup.
    ///
    ///  * GstVideoDecoder calls `set_format` to inform the subclass of caps
    ///  describing input video data that it is about to receive, including
    ///  possibly configuration data.
    ///  While unlikely, it might be called more than once, if changing input
    ///  parameters require reconfiguration.
    ///
    ///  * Incoming data buffers are processed as needed, described in Data
    ///  Processing below.
    ///
    ///  * GstVideoDecoder calls `stop` at end of all processing.
    ///
    /// ## Data processing
    ///
    ///  * The base class gathers input data, and optionally allows subclass
    ///  to parse this into subsequently manageable chunks, typically
    ///  corresponding to and referred to as 'frames'.
    ///
    ///  * Each input frame is provided in turn to the subclass' `handle_frame`
    ///  callback.
    ///  * When the subclass enables the subframe mode with `gst_video_decoder_set_subframe_mode`,
    ///  the base class will provide to the subclass the same input frame with
    ///  different input buffers to the subclass `handle_frame`
    ///  callback. During this call, the subclass needs to take
    ///  ownership of the input_buffer as [`VideoCodecFrame`][crate::VideoCodecFrame]
    ///  will have been changed before the next subframe buffer is received.
    ///  The subclass will call `gst_video_decoder_have_last_subframe`
    ///  when a new input frame can be created by the base class.
    ///  Every subframe will share the same [`VideoCodecFrame`][crate::VideoCodecFrame]
    ///  to write the decoding result. The subclass is responsible to protect
    ///  its access.
    ///
    ///  * If codec processing results in decoded data, the subclass should call
    ///  [`VideoDecoderExt::finish_frame()`][crate::prelude::VideoDecoderExt::finish_frame()] to have decoded data pushed
    ///  downstream. In subframe mode
    ///  the subclass should call [`VideoDecoderExt::finish_subframe()`][crate::prelude::VideoDecoderExt::finish_subframe()] until the
    ///  last subframe where it should call [`VideoDecoderExt::finish_frame()`][crate::prelude::VideoDecoderExt::finish_frame()].
    ///  The subclass can detect the last subframe using GST_VIDEO_BUFFER_FLAG_MARKER
    ///  on buffers or using its own logic to collect the subframes.
    ///  In case of decoding failure, the subclass must call
    ///  [`VideoDecoderExt::drop_frame()`][crate::prelude::VideoDecoderExt::drop_frame()] or [`VideoDecoderExt::drop_subframe()`][crate::prelude::VideoDecoderExt::drop_subframe()],
    ///  to allow the base class to do timestamp and offset tracking, and possibly
    ///  to requeue the frame for a later attempt in the case of reverse playback.
    ///
    /// ## Shutdown phase
    ///
    ///  * The GstVideoDecoder class calls `stop` to inform the subclass that data
    ///  parsing will be stopped.
    ///
    /// ## Additional Notes
    ///
    ///  * Seeking/Flushing
    ///
    ///  * When the pipeline is seeked or otherwise flushed, the subclass is
    ///  informed via a call to its `reset` callback, with the hard parameter
    ///  set to true. This indicates the subclass should drop any internal data
    ///  queues and timestamps and prepare for a fresh set of buffers to arrive
    ///  for parsing and decoding.
    ///
    ///  * End Of Stream
    ///
    ///  * At end-of-stream, the subclass `parse` function may be called some final
    ///  times with the at_eos parameter set to true, indicating that the element
    ///  should not expect any more data to be arriving, and it should parse and
    ///  remaining frames and call [`VideoDecoderExt::have_frame()`][crate::prelude::VideoDecoderExt::have_frame()] if possible.
    ///
    /// The subclass is responsible for providing pad template caps for
    /// source and sink pads. The pads need to be named "sink" and "src". It also
    /// needs to provide information about the output caps, when they are known.
    /// This may be when the base class calls the subclass' `set_format` function,
    /// though it might be during decoding, before calling
    /// [`VideoDecoderExt::finish_frame()`][crate::prelude::VideoDecoderExt::finish_frame()]. This is done via
    /// [`VideoDecoderExtManual::set_output_state()`][crate::prelude::VideoDecoderExtManual::set_output_state()]
    ///
    /// The subclass is also responsible for providing (presentation) timestamps
    /// (likely based on corresponding input ones). If that is not applicable
    /// or possible, the base class provides limited framerate based interpolation.
    ///
    /// Similarly, the base class provides some limited (legacy) seeking support
    /// if specifically requested by the subclass, as full-fledged support
    /// should rather be left to upstream demuxer, parser or alike. This simple
    /// approach caters for seeking and duration reporting using estimated input
    /// bitrates. To enable it, a subclass should call
    /// [`VideoDecoderExt::set_estimate_rate()`][crate::prelude::VideoDecoderExt::set_estimate_rate()] to enable handling of incoming
    /// byte-streams.
    ///
    /// The base class provides some support for reverse playback, in particular
    /// in case incoming data is not packetized or upstream does not provide
    /// fragments on keyframe boundaries. However, the subclass should then be
    /// prepared for the parsing and frame processing stage to occur separately
    /// (in normal forward processing, the latter immediately follows the former),
    /// The subclass also needs to ensure the parsing stage properly marks
    /// keyframes, unless it knows the upstream elements will do so properly for
    /// incoming data.
    ///
    /// The bare minimum that a functional subclass needs to implement is:
    ///
    ///  * Provide pad templates
    ///  * Inform the base class of output caps via
    ///  [`VideoDecoderExtManual::set_output_state()`][crate::prelude::VideoDecoderExtManual::set_output_state()]
    ///
    ///  * Parse input data, if it is not considered packetized from upstream
    ///  Data will be provided to `parse` which should invoke
    ///  [`VideoDecoderExt::add_to_frame()`][crate::prelude::VideoDecoderExt::add_to_frame()] and [`VideoDecoderExt::have_frame()`][crate::prelude::VideoDecoderExt::have_frame()] to
    ///  separate the data belonging to each video frame.
    ///
    ///  * Accept data in `handle_frame` and provide decoded results to
    ///  [`VideoDecoderExt::finish_frame()`][crate::prelude::VideoDecoderExt::finish_frame()], or call [`VideoDecoderExt::drop_frame()`][crate::prelude::VideoDecoderExt::drop_frame()].
    ///
    /// This is an Abstract Base Class, you cannot instantiate it.
    ///
    /// ## Properties
    ///
    ///
    /// #### `automatic-request-sync-point-flags`
    ///  GstVideoDecoderRequestSyncPointFlags to use for the automatically
    /// requested sync points if `automatic-request-sync-points` is enabled.
    ///
    /// Readable | Writeable
    ///
    ///
    /// #### `automatic-request-sync-points`
    ///  If set to [`true`] the decoder will automatically request sync points when
    /// it seems like a good idea, e.g. if the first frames are not key frames or
    /// if packet loss was reported by upstream.
    ///
    /// Readable | Writeable
    ///
    ///
    /// #### `discard-corrupted-frames`
    ///  If set to [`true`] the decoder will discard frames that are marked as
    /// corrupted instead of outputting them.
    ///
    /// Readable | Writeable
    ///
    ///
    /// #### `max-errors`
    ///  Maximum number of tolerated consecutive decode errors. See
    /// [`VideoDecoderExt::set_max_errors()`][crate::prelude::VideoDecoderExt::set_max_errors()] for more details.
    ///
    /// Readable | Writeable
    ///
    ///
    /// #### `min-force-key-unit-interval`
    ///  Minimum interval between force-key-unit events sent upstream by the
    /// decoder. Setting this to 0 will cause every event to be handled, setting
    /// this to `GST_CLOCK_TIME_NONE` will cause every event to be ignored.
    ///
    /// See `gst_video_event_new_upstream_force_key_unit()` for more details about
    /// force-key-unit events.
    ///
    /// Readable | Writeable
    ///
    ///
    /// #### `qos`
    ///  If set to [`true`] the decoder will handle QoS events received
    /// from downstream elements.
    /// This includes dropping output frames which are detected as late
    /// using the metrics reported by those events.
    ///
    /// Readable | Writeable
    /// <details><summary><h4>Object</h4></summary>
    ///
    ///
    /// #### `name`
    ///  Readable | Writeable | Construct
    ///
    ///
    /// #### `parent`
    ///  The parent of the object. Please note, that when changing the 'parent'
    /// property, we don't emit [`notify`][struct@crate::glib::Object#notify] and [`deep-notify`][struct@crate::gst::Object#deep-notify]
    /// signals due to locking issues. In some cases one can use
    /// `GstBin::element-added` or `GstBin::element-removed` signals on the parent to
    /// achieve a similar effect.
    ///
    /// Readable | Writeable
    /// </details>
    ///
    /// # Implements
    ///
    /// [`VideoDecoderExt`][trait@crate::prelude::VideoDecoderExt], [`trait@gst::prelude::ElementExt`], [`trait@gst::prelude::ObjectExt`], [`trait@glib::ObjectExt`], [`VideoDecoderExtManual`][trait@crate::prelude::VideoDecoderExtManual]
    #[doc(alias = "GstVideoDecoder")]
    pub struct VideoDecoder(Object<ffi::GstVideoDecoder, ffi::GstVideoDecoderClass>) @extends gst::Element, gst::Object;

    match fn {
        type_ => || ffi::gst_video_decoder_get_type(),
    }
}

impl VideoDecoder {
    pub const NONE: Option<&'static VideoDecoder> = None;
}

unsafe impl Send for VideoDecoder {}
unsafe impl Sync for VideoDecoder {}

mod sealed {
    pub trait Sealed {}
    impl<T: super::IsA<super::VideoDecoder>> Sealed for T {}
}

/// Trait containing all [`struct@VideoDecoder`] methods.
///
/// # Implementors
///
/// [`VideoDecoder`][struct@crate::VideoDecoder]
pub trait VideoDecoderExt: IsA<VideoDecoder> + sealed::Sealed + 'static {
    /// Removes next `n_bytes` of input data and adds it to currently parsed frame.
    /// ## `n_bytes`
    /// the number of bytes to add
    #[doc(alias = "gst_video_decoder_add_to_frame")]
    fn add_to_frame(&self, n_bytes: i32) {
        unsafe {
            ffi::gst_video_decoder_add_to_frame(self.as_ref().to_glib_none().0, n_bytes);
        }
    }

    /// Helper function that allocates a buffer to hold a video frame for `self`'s
    /// current [`VideoCodecState`][crate::VideoCodecState].
    ///
    /// You should use [`VideoDecoderExtManual::allocate_output_frame()`][crate::prelude::VideoDecoderExtManual::allocate_output_frame()] instead of this
    /// function, if possible at all.
    ///
    /// # Returns
    ///
    /// allocated buffer, or NULL if no buffer could be
    ///  allocated (e.g. when downstream is flushing or shutting down)
    #[doc(alias = "gst_video_decoder_allocate_output_buffer")]
    fn allocate_output_buffer(&self) -> Result<gst::Buffer, glib::BoolError> {
        unsafe {
            Option::<_>::from_glib_full(ffi::gst_video_decoder_allocate_output_buffer(
                self.as_ref().to_glib_none().0,
            ))
            .ok_or_else(|| glib::bool_error!("Failed to allocate output buffer"))
        }
    }

    /// Similar to [`finish_frame()`][Self::finish_frame()], but drops `frame` in any
    /// case and posts a QoS message with the frame's details on the bus.
    /// In any case, the frame is considered finished and released.
    /// ## `frame`
    /// the [`VideoCodecFrame`][crate::VideoCodecFrame] to drop
    ///
    /// # Returns
    ///
    /// a [`gst::FlowReturn`][crate::gst::FlowReturn], usually GST_FLOW_OK.
    #[doc(alias = "gst_video_decoder_drop_frame")]
    fn drop_frame(&self, frame: VideoCodecFrame) -> Result<gst::FlowSuccess, gst::FlowError> {
        unsafe {
            try_from_glib(ffi::gst_video_decoder_drop_frame(
                self.as_ref().to_glib_none().0,
                frame.into_glib_ptr(),
            ))
        }
    }

    /// Drops input data.
    /// The frame is not considered finished until the whole frame
    /// is finished or dropped by the subclass.
    /// ## `frame`
    /// the [`VideoCodecFrame`][crate::VideoCodecFrame]
    ///
    /// # Returns
    ///
    /// a [`gst::FlowReturn`][crate::gst::FlowReturn], usually GST_FLOW_OK.
    #[cfg(feature = "v1_20")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_20")))]
    #[doc(alias = "gst_video_decoder_drop_subframe")]
    fn drop_subframe(&self, frame: VideoCodecFrame) -> Result<gst::FlowSuccess, gst::FlowError> {
        unsafe {
            try_from_glib(ffi::gst_video_decoder_drop_subframe(
                self.as_ref().to_glib_none().0,
                frame.into_glib_ptr(),
            ))
        }
    }

    /// `frame` should have a valid decoded data buffer, whose metadata fields
    /// are then appropriately set according to frame data and pushed downstream.
    /// If no output data is provided, `frame` is considered skipped.
    /// In any case, the frame is considered finished and released.
    ///
    /// After calling this function the output buffer of the frame is to be
    /// considered read-only. This function will also change the metadata
    /// of the buffer.
    /// ## `frame`
    /// a decoded [`VideoCodecFrame`][crate::VideoCodecFrame]
    ///
    /// # Returns
    ///
    /// a [`gst::FlowReturn`][crate::gst::FlowReturn] resulting from sending data downstream
    #[doc(alias = "gst_video_decoder_finish_frame")]
    fn finish_frame(&self, frame: VideoCodecFrame) -> Result<gst::FlowSuccess, gst::FlowError> {
        unsafe {
            try_from_glib(ffi::gst_video_decoder_finish_frame(
                self.as_ref().to_glib_none().0,
                frame.into_glib_ptr(),
            ))
        }
    }

    /// Indicate that a subframe has been finished to be decoded
    /// by the subclass. This method should be called for all subframes
    /// except the last subframe where [`finish_frame()`][Self::finish_frame()]
    /// should be called instead.
    /// ## `frame`
    /// the [`VideoCodecFrame`][crate::VideoCodecFrame]
    ///
    /// # Returns
    ///
    /// a [`gst::FlowReturn`][crate::gst::FlowReturn], usually GST_FLOW_OK.
    #[cfg(feature = "v1_20")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_20")))]
    #[doc(alias = "gst_video_decoder_finish_subframe")]
    fn finish_subframe(&self, frame: VideoCodecFrame) -> Result<gst::FlowSuccess, gst::FlowError> {
        unsafe {
            try_from_glib(ffi::gst_video_decoder_finish_subframe(
                self.as_ref().to_glib_none().0,
                frame.into_glib_ptr(),
            ))
        }
    }

    ///
    /// # Returns
    ///
    /// the instance of the [`gst::BufferPool`][crate::gst::BufferPool] used
    /// by the decoder; free it after use it
    #[doc(alias = "gst_video_decoder_get_buffer_pool")]
    #[doc(alias = "get_buffer_pool")]
    fn buffer_pool(&self) -> Option<gst::BufferPool> {
        unsafe {
            from_glib_full(ffi::gst_video_decoder_get_buffer_pool(
                self.as_ref().to_glib_none().0,
            ))
        }
    }

    ///
    /// # Returns
    ///
    /// currently configured byte to time conversion setting
    #[doc(alias = "gst_video_decoder_get_estimate_rate")]
    #[doc(alias = "get_estimate_rate")]
    fn estimate_rate(&self) -> i32 {
        unsafe { ffi::gst_video_decoder_get_estimate_rate(self.as_ref().to_glib_none().0) }
    }

    /// Determines maximum possible decoding time for `frame` that will
    /// allow it to decode and arrive in time (as determined by QoS events).
    /// In particular, a negative result means decoding in time is no longer possible
    /// and should therefore occur as soon/skippy as possible.
    /// ## `frame`
    /// a [`VideoCodecFrame`][crate::VideoCodecFrame]
    ///
    /// # Returns
    ///
    /// max decoding time.
    #[doc(alias = "gst_video_decoder_get_max_decode_time")]
    #[doc(alias = "get_max_decode_time")]
    fn max_decode_time(&self, frame: &VideoCodecFrame) -> gst::ClockTimeDiff {
        unsafe {
            ffi::gst_video_decoder_get_max_decode_time(
                self.as_ref().to_glib_none().0,
                frame.to_glib_none().0,
            )
        }
    }

    ///
    /// # Returns
    ///
    /// currently configured decoder tolerated error count.
    #[doc(alias = "gst_video_decoder_get_max_errors")]
    #[doc(alias = "get_max_errors")]
    fn max_errors(&self) -> i32 {
        unsafe { ffi::gst_video_decoder_get_max_errors(self.as_ref().to_glib_none().0) }
    }

    /// Queries decoder required format handling.
    ///
    /// # Returns
    ///
    /// [`true`] if required format handling is enabled.
    #[doc(alias = "gst_video_decoder_get_needs_format")]
    #[doc(alias = "get_needs_format")]
    fn needs_format(&self) -> bool {
        unsafe {
            from_glib(ffi::gst_video_decoder_get_needs_format(
                self.as_ref().to_glib_none().0,
            ))
        }
    }

    /// Queries if the decoder requires a sync point before it starts outputting
    /// data in the beginning.
    ///
    /// # Returns
    ///
    /// [`true`] if a sync point is required in the beginning.
    #[cfg(feature = "v1_20")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_20")))]
    #[doc(alias = "gst_video_decoder_get_needs_sync_point")]
    #[doc(alias = "get_needs_sync_point")]
    fn needs_sync_point(&self) -> bool {
        unsafe {
            from_glib(ffi::gst_video_decoder_get_needs_sync_point(
                self.as_ref().to_glib_none().0,
            ))
        }
    }

    /// Queries whether input data is considered packetized or not by the
    /// base class.
    ///
    /// # Returns
    ///
    /// TRUE if input data is considered packetized.
    #[doc(alias = "gst_video_decoder_get_packetized")]
    #[doc(alias = "get_packetized")]
    fn is_packetized(&self) -> bool {
        unsafe {
            from_glib(ffi::gst_video_decoder_get_packetized(
                self.as_ref().to_glib_none().0,
            ))
        }
    }

    /// Returns the number of bytes previously added to the current frame
    /// by calling [`add_to_frame()`][Self::add_to_frame()].
    ///
    /// # Returns
    ///
    /// The number of bytes pending for the current frame
    #[doc(alias = "gst_video_decoder_get_pending_frame_size")]
    #[doc(alias = "get_pending_frame_size")]
    fn pending_frame_size(&self) -> usize {
        unsafe { ffi::gst_video_decoder_get_pending_frame_size(self.as_ref().to_glib_none().0) }
    }

    ///
    /// # Returns
    ///
    /// The current QoS proportion.
    #[doc(alias = "gst_video_decoder_get_qos_proportion")]
    #[doc(alias = "get_qos_proportion")]
    fn qos_proportion(&self) -> f64 {
        unsafe { ffi::gst_video_decoder_get_qos_proportion(self.as_ref().to_glib_none().0) }
    }

    /// Queries whether input data is considered as subframes or not by the
    /// base class. If FALSE, each input buffer will be considered as a full
    /// frame.
    ///
    /// # Returns
    ///
    /// TRUE if input data is considered as sub frames.
    #[cfg(feature = "v1_20")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_20")))]
    #[doc(alias = "gst_video_decoder_get_subframe_mode")]
    #[doc(alias = "get_subframe_mode")]
    fn is_subframe_mode(&self) -> bool {
        unsafe {
            from_glib(ffi::gst_video_decoder_get_subframe_mode(
                self.as_ref().to_glib_none().0,
            ))
        }
    }

    /// Gathers all data collected for currently parsed frame, gathers corresponding
    /// metadata and passes it along for further processing, i.e. `handle_frame`.
    ///
    /// # Returns
    ///
    /// a [`gst::FlowReturn`][crate::gst::FlowReturn]
    #[doc(alias = "gst_video_decoder_have_frame")]
    fn have_frame(&self) -> Result<gst::FlowSuccess, gst::FlowError> {
        unsafe {
            try_from_glib(ffi::gst_video_decoder_have_frame(
                self.as_ref().to_glib_none().0,
            ))
        }
    }

    /// Indicates that the last subframe has been processed by the decoder
    /// in `frame`. This will release the current frame in video decoder
    /// allowing to receive new frames from upstream elements. This method
    /// must be called in the subclass `handle_frame` callback.
    /// ## `frame`
    /// the [`VideoCodecFrame`][crate::VideoCodecFrame] to update
    ///
    /// # Returns
    ///
    /// a [`gst::FlowReturn`][crate::gst::FlowReturn], usually GST_FLOW_OK.
    #[cfg(feature = "v1_20")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_20")))]
    #[doc(alias = "gst_video_decoder_have_last_subframe")]
    fn have_last_subframe(
        &self,
        frame: &VideoCodecFrame,
    ) -> Result<gst::FlowSuccess, gst::FlowError> {
        unsafe {
            try_from_glib(ffi::gst_video_decoder_have_last_subframe(
                self.as_ref().to_glib_none().0,
                frame.to_glib_none().0,
            ))
        }
    }

    /// Sets the audio decoder tags and how they should be merged with any
    /// upstream stream tags. This will override any tags previously-set
    /// with `gst_audio_decoder_merge_tags()`.
    ///
    /// Note that this is provided for convenience, and the subclass is
    /// not required to use this and can still do tag handling on its own.
    ///
    /// MT safe.
    /// ## `tags`
    /// a [`gst::TagList`][crate::gst::TagList] to merge, or NULL to unset
    ///  previously-set tags
    /// ## `mode`
    /// the [`gst::TagMergeMode`][crate::gst::TagMergeMode] to use, usually [`gst::TagMergeMode::Replace`][crate::gst::TagMergeMode::Replace]
    #[doc(alias = "gst_video_decoder_merge_tags")]
    fn merge_tags(&self, tags: Option<&gst::TagList>, mode: gst::TagMergeMode) {
        unsafe {
            ffi::gst_video_decoder_merge_tags(
                self.as_ref().to_glib_none().0,
                tags.to_glib_none().0,
                mode.into_glib(),
            );
        }
    }

    /// Returns caps that express `caps` (or sink template caps if `caps` == NULL)
    /// restricted to resolution/format/... combinations supported by downstream
    /// elements.
    /// ## `caps`
    /// initial caps
    /// ## `filter`
    /// filter caps
    ///
    /// # Returns
    ///
    /// a [`gst::Caps`][crate::gst::Caps] owned by caller
    #[doc(alias = "gst_video_decoder_proxy_getcaps")]
    fn proxy_getcaps(&self, caps: Option<&gst::Caps>, filter: Option<&gst::Caps>) -> gst::Caps {
        unsafe {
            from_glib_full(ffi::gst_video_decoder_proxy_getcaps(
                self.as_ref().to_glib_none().0,
                caps.to_glib_none().0,
                filter.to_glib_none().0,
            ))
        }
    }

    /// Similar to [`drop_frame()`][Self::drop_frame()], but simply releases `frame`
    /// without any processing other than removing it from list of pending frames,
    /// after which it is considered finished and released.
    /// ## `frame`
    /// the [`VideoCodecFrame`][crate::VideoCodecFrame] to release
    #[doc(alias = "gst_video_decoder_release_frame")]
    fn release_frame(&self, frame: VideoCodecFrame) {
        unsafe {
            ffi::gst_video_decoder_release_frame(
                self.as_ref().to_glib_none().0,
                frame.into_glib_ptr(),
            );
        }
    }

    /// Allows the [`VideoDecoder`][crate::VideoDecoder] subclass to request from the base class that
    /// a new sync should be requested from upstream, and that `frame` was the frame
    /// when the subclass noticed that a new sync point is required. A reason for
    /// the subclass to do this could be missing reference frames, for example.
    ///
    /// The base class will then request a new sync point from upstream as long as
    /// the time that passed since the last one is exceeding
    /// [`min-force-key-unit-interval`][struct@crate::VideoDecoder#min-force-key-unit-interval].
    ///
    /// The subclass can signal via `flags` how the frames until the next sync point
    /// should be handled:
    ///
    ///  * If [`VideoDecoderRequestSyncPointFlags::DISCARD_INPUT`][crate::VideoDecoderRequestSyncPointFlags::DISCARD_INPUT] is selected then
    ///  all following input frames until the next sync point are discarded.
    ///  This can be useful if the lack of a sync point will prevent all further
    ///  decoding and the decoder implementation is not very robust in handling
    ///  missing references frames.
    ///  * If [`VideoDecoderRequestSyncPointFlags::CORRUPT_OUTPUT`][crate::VideoDecoderRequestSyncPointFlags::CORRUPT_OUTPUT] is selected
    ///  then all output frames following `frame` are marked as corrupted via
    ///  `GST_BUFFER_FLAG_CORRUPTED`. Corrupted frames can be automatically
    ///  dropped by the base class, see [`discard-corrupted-frames`][struct@crate::VideoDecoder#discard-corrupted-frames].
    ///  Subclasses can manually mark frames as corrupted via [`VideoCodecFrameFlags::CORRUPTED`][crate::VideoCodecFrameFlags::CORRUPTED]
    ///  before calling [`finish_frame()`][Self::finish_frame()].
    /// ## `frame`
    /// a [`VideoCodecFrame`][crate::VideoCodecFrame]
    /// ## `flags`
    /// [`VideoDecoderRequestSyncPointFlags`][crate::VideoDecoderRequestSyncPointFlags]
    #[cfg(feature = "v1_20")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_20")))]
    #[doc(alias = "gst_video_decoder_request_sync_point")]
    fn request_sync_point(
        &self,
        frame: &VideoCodecFrame,
        flags: VideoDecoderRequestSyncPointFlags,
    ) {
        unsafe {
            ffi::gst_video_decoder_request_sync_point(
                self.as_ref().to_glib_none().0,
                frame.to_glib_none().0,
                flags.into_glib(),
            );
        }
    }

    /// Allows baseclass to perform byte to time estimated conversion.
    /// ## `enabled`
    /// whether to enable byte to time conversion
    #[doc(alias = "gst_video_decoder_set_estimate_rate")]
    fn set_estimate_rate(&self, enabled: bool) {
        unsafe {
            ffi::gst_video_decoder_set_estimate_rate(
                self.as_ref().to_glib_none().0,
                enabled.into_glib(),
            );
        }
    }

    /// Sets numbers of tolerated decoder errors, where a tolerated one is then only
    /// warned about, but more than tolerated will lead to fatal error. You can set
    /// -1 for never returning fatal errors. Default is set to
    /// GST_VIDEO_DECODER_MAX_ERRORS.
    ///
    /// The '-1' option was added in 1.4
    /// ## `num`
    /// max tolerated errors
    #[doc(alias = "gst_video_decoder_set_max_errors")]
    fn set_max_errors(&self, num: i32) {
        unsafe {
            ffi::gst_video_decoder_set_max_errors(self.as_ref().to_glib_none().0, num);
        }
    }

    /// Configures decoder format needs. If enabled, subclass needs to be
    /// negotiated with format caps before it can process any data. It will then
    /// never be handed any data before it has been configured.
    /// Otherwise, it might be handed data without having been configured and
    /// is then expected being able to do so either by default
    /// or based on the input data.
    /// ## `enabled`
    /// new state
    #[doc(alias = "gst_video_decoder_set_needs_format")]
    fn set_needs_format(&self, enabled: bool) {
        unsafe {
            ffi::gst_video_decoder_set_needs_format(
                self.as_ref().to_glib_none().0,
                enabled.into_glib(),
            );
        }
    }

    /// Configures whether the decoder requires a sync point before it starts
    /// outputting data in the beginning. If enabled, the base class will discard
    /// all non-sync point frames in the beginning and after a flush and does not
    /// pass it to the subclass.
    ///
    /// If the first frame is not a sync point, the base class will request a sync
    /// point via the force-key-unit event.
    /// ## `enabled`
    /// new state
    #[cfg(feature = "v1_20")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_20")))]
    #[doc(alias = "gst_video_decoder_set_needs_sync_point")]
    fn set_needs_sync_point(&self, enabled: bool) {
        unsafe {
            ffi::gst_video_decoder_set_needs_sync_point(
                self.as_ref().to_glib_none().0,
                enabled.into_glib(),
            );
        }
    }

    /// Allows baseclass to consider input data as packetized or not. If the
    /// input is packetized, then the `parse` method will not be called.
    /// ## `packetized`
    /// whether the input data should be considered as packetized.
    #[doc(alias = "gst_video_decoder_set_packetized")]
    fn set_packetized(&self, packetized: bool) {
        unsafe {
            ffi::gst_video_decoder_set_packetized(
                self.as_ref().to_glib_none().0,
                packetized.into_glib(),
            );
        }
    }

    /// If this is set to TRUE, it informs the base class that the subclass
    /// can receive the data at a granularity lower than one frame.
    ///
    /// Note that in this mode, the subclass has two options. It can either
    /// require the presence of a GST_VIDEO_BUFFER_FLAG_MARKER to mark the
    /// end of a frame. Or it can operate in such a way that it will decode
    /// a single frame at a time. In this second case, every buffer that
    /// arrives to the element is considered part of the same frame until
    /// [`finish_frame()`][Self::finish_frame()] is called.
    ///
    /// In either case, the same [`VideoCodecFrame`][crate::VideoCodecFrame] will be passed to the
    /// GstVideoDecoderClass:handle_frame vmethod repeatedly with a
    /// different GstVideoCodecFrame:input_buffer every time until the end of the
    /// frame has been signaled using either method.
    /// This method must be called during the decoder subclass `set_format` call.
    /// ## `subframe_mode`
    /// whether the input data should be considered as subframes.
    #[cfg(feature = "v1_20")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_20")))]
    #[doc(alias = "gst_video_decoder_set_subframe_mode")]
    fn set_subframe_mode(&self, subframe_mode: bool) {
        unsafe {
            ffi::gst_video_decoder_set_subframe_mode(
                self.as_ref().to_glib_none().0,
                subframe_mode.into_glib(),
            );
        }
    }

    /// Lets [`VideoDecoder`][crate::VideoDecoder] sub-classes decide if they want the sink pad
    /// to use the default pad query handler to reply to accept-caps queries.
    ///
    /// By setting this to true it is possible to further customize the default
    /// handler with `GST_PAD_SET_ACCEPT_INTERSECT` and
    /// `GST_PAD_SET_ACCEPT_TEMPLATE`
    /// ## `use_`
    /// if the default pad accept-caps query handling should be used
    #[doc(alias = "gst_video_decoder_set_use_default_pad_acceptcaps")]
    fn set_use_default_pad_acceptcaps(&self, use_: bool) {
        unsafe {
            ffi::gst_video_decoder_set_use_default_pad_acceptcaps(
                self.as_ref().to_glib_none().0,
                use_.into_glib(),
            );
        }
    }

    /// GstVideoDecoderRequestSyncPointFlags to use for the automatically
    /// requested sync points if `automatic-request-sync-points` is enabled.
    #[cfg(feature = "v1_20")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_20")))]
    #[doc(alias = "automatic-request-sync-point-flags")]
    fn automatic_request_sync_point_flags(&self) -> VideoDecoderRequestSyncPointFlags {
        ObjectExt::property(self.as_ref(), "automatic-request-sync-point-flags")
    }

    /// GstVideoDecoderRequestSyncPointFlags to use for the automatically
    /// requested sync points if `automatic-request-sync-points` is enabled.
    #[cfg(feature = "v1_20")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_20")))]
    #[doc(alias = "automatic-request-sync-point-flags")]
    fn set_automatic_request_sync_point_flags(
        &self,
        automatic_request_sync_point_flags: VideoDecoderRequestSyncPointFlags,
    ) {
        ObjectExt::set_property(
            self.as_ref(),
            "automatic-request-sync-point-flags",
            automatic_request_sync_point_flags,
        )
    }

    /// If set to [`true`] the decoder will automatically request sync points when
    /// it seems like a good idea, e.g. if the first frames are not key frames or
    /// if packet loss was reported by upstream.
    #[cfg(feature = "v1_20")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_20")))]
    #[doc(alias = "automatic-request-sync-points")]
    fn is_automatic_request_sync_points(&self) -> bool {
        ObjectExt::property(self.as_ref(), "automatic-request-sync-points")
    }

    /// If set to [`true`] the decoder will automatically request sync points when
    /// it seems like a good idea, e.g. if the first frames are not key frames or
    /// if packet loss was reported by upstream.
    #[cfg(feature = "v1_20")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_20")))]
    #[doc(alias = "automatic-request-sync-points")]
    fn set_automatic_request_sync_points(&self, automatic_request_sync_points: bool) {
        ObjectExt::set_property(
            self.as_ref(),
            "automatic-request-sync-points",
            automatic_request_sync_points,
        )
    }

    /// If set to [`true`] the decoder will discard frames that are marked as
    /// corrupted instead of outputting them.
    #[cfg(feature = "v1_20")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_20")))]
    #[doc(alias = "discard-corrupted-frames")]
    fn is_discard_corrupted_frames(&self) -> bool {
        ObjectExt::property(self.as_ref(), "discard-corrupted-frames")
    }

    /// If set to [`true`] the decoder will discard frames that are marked as
    /// corrupted instead of outputting them.
    #[cfg(feature = "v1_20")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_20")))]
    #[doc(alias = "discard-corrupted-frames")]
    fn set_discard_corrupted_frames(&self, discard_corrupted_frames: bool) {
        ObjectExt::set_property(
            self.as_ref(),
            "discard-corrupted-frames",
            discard_corrupted_frames,
        )
    }

    /// Minimum interval between force-key-unit events sent upstream by the
    /// decoder. Setting this to 0 will cause every event to be handled, setting
    /// this to `GST_CLOCK_TIME_NONE` will cause every event to be ignored.
    ///
    /// See `gst_video_event_new_upstream_force_key_unit()` for more details about
    /// force-key-unit events.
    #[cfg(feature = "v1_20")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_20")))]
    #[doc(alias = "min-force-key-unit-interval")]
    fn min_force_key_unit_interval(&self) -> u64 {
        ObjectExt::property(self.as_ref(), "min-force-key-unit-interval")
    }

    /// Minimum interval between force-key-unit events sent upstream by the
    /// decoder. Setting this to 0 will cause every event to be handled, setting
    /// this to `GST_CLOCK_TIME_NONE` will cause every event to be ignored.
    ///
    /// See `gst_video_event_new_upstream_force_key_unit()` for more details about
    /// force-key-unit events.
    #[cfg(feature = "v1_20")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_20")))]
    #[doc(alias = "min-force-key-unit-interval")]
    fn set_min_force_key_unit_interval(&self, min_force_key_unit_interval: u64) {
        ObjectExt::set_property(
            self.as_ref(),
            "min-force-key-unit-interval",
            min_force_key_unit_interval,
        )
    }

    /// If set to [`true`] the decoder will handle QoS events received
    /// from downstream elements.
    /// This includes dropping output frames which are detected as late
    /// using the metrics reported by those events.
    #[cfg(feature = "v1_18")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_18")))]
    fn is_qos(&self) -> bool {
        ObjectExt::property(self.as_ref(), "qos")
    }

    /// If set to [`true`] the decoder will handle QoS events received
    /// from downstream elements.
    /// This includes dropping output frames which are detected as late
    /// using the metrics reported by those events.
    #[cfg(feature = "v1_18")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_18")))]
    fn set_qos(&self, qos: bool) {
        ObjectExt::set_property(self.as_ref(), "qos", qos)
    }

    #[cfg(feature = "v1_20")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_20")))]
    #[doc(alias = "automatic-request-sync-point-flags")]
    fn connect_automatic_request_sync_point_flags_notify<F: Fn(&Self) + Send + Sync + 'static>(
        &self,
        f: F,
    ) -> SignalHandlerId {
        unsafe extern "C" fn notify_automatic_request_sync_point_flags_trampoline<
            P: IsA<VideoDecoder>,
            F: Fn(&P) + Send + Sync + 'static,
        >(
            this: *mut ffi::GstVideoDecoder,
            _param_spec: glib::ffi::gpointer,
            f: glib::ffi::gpointer,
        ) {
            let f: &F = &*(f as *const F);
            f(VideoDecoder::from_glib_borrow(this).unsafe_cast_ref())
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"notify::automatic-request-sync-point-flags\0".as_ptr() as *const _,
                Some(std::mem::transmute::<_, unsafe extern "C" fn()>(
                    notify_automatic_request_sync_point_flags_trampoline::<Self, F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }

    #[cfg(feature = "v1_20")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_20")))]
    #[doc(alias = "automatic-request-sync-points")]
    fn connect_automatic_request_sync_points_notify<F: Fn(&Self) + Send + Sync + 'static>(
        &self,
        f: F,
    ) -> SignalHandlerId {
        unsafe extern "C" fn notify_automatic_request_sync_points_trampoline<
            P: IsA<VideoDecoder>,
            F: Fn(&P) + Send + Sync + 'static,
        >(
            this: *mut ffi::GstVideoDecoder,
            _param_spec: glib::ffi::gpointer,
            f: glib::ffi::gpointer,
        ) {
            let f: &F = &*(f as *const F);
            f(VideoDecoder::from_glib_borrow(this).unsafe_cast_ref())
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"notify::automatic-request-sync-points\0".as_ptr() as *const _,
                Some(std::mem::transmute::<_, unsafe extern "C" fn()>(
                    notify_automatic_request_sync_points_trampoline::<Self, F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }

    #[cfg(feature = "v1_20")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_20")))]
    #[doc(alias = "discard-corrupted-frames")]
    fn connect_discard_corrupted_frames_notify<F: Fn(&Self) + Send + Sync + 'static>(
        &self,
        f: F,
    ) -> SignalHandlerId {
        unsafe extern "C" fn notify_discard_corrupted_frames_trampoline<
            P: IsA<VideoDecoder>,
            F: Fn(&P) + Send + Sync + 'static,
        >(
            this: *mut ffi::GstVideoDecoder,
            _param_spec: glib::ffi::gpointer,
            f: glib::ffi::gpointer,
        ) {
            let f: &F = &*(f as *const F);
            f(VideoDecoder::from_glib_borrow(this).unsafe_cast_ref())
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"notify::discard-corrupted-frames\0".as_ptr() as *const _,
                Some(std::mem::transmute::<_, unsafe extern "C" fn()>(
                    notify_discard_corrupted_frames_trampoline::<Self, F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }

    #[cfg(feature = "v1_18")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_18")))]
    #[doc(alias = "max-errors")]
    fn connect_max_errors_notify<F: Fn(&Self) + Send + Sync + 'static>(
        &self,
        f: F,
    ) -> SignalHandlerId {
        unsafe extern "C" fn notify_max_errors_trampoline<
            P: IsA<VideoDecoder>,
            F: Fn(&P) + Send + Sync + 'static,
        >(
            this: *mut ffi::GstVideoDecoder,
            _param_spec: glib::ffi::gpointer,
            f: glib::ffi::gpointer,
        ) {
            let f: &F = &*(f as *const F);
            f(VideoDecoder::from_glib_borrow(this).unsafe_cast_ref())
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"notify::max-errors\0".as_ptr() as *const _,
                Some(std::mem::transmute::<_, unsafe extern "C" fn()>(
                    notify_max_errors_trampoline::<Self, F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }

    #[cfg(feature = "v1_20")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_20")))]
    #[doc(alias = "min-force-key-unit-interval")]
    fn connect_min_force_key_unit_interval_notify<F: Fn(&Self) + Send + Sync + 'static>(
        &self,
        f: F,
    ) -> SignalHandlerId {
        unsafe extern "C" fn notify_min_force_key_unit_interval_trampoline<
            P: IsA<VideoDecoder>,
            F: Fn(&P) + Send + Sync + 'static,
        >(
            this: *mut ffi::GstVideoDecoder,
            _param_spec: glib::ffi::gpointer,
            f: glib::ffi::gpointer,
        ) {
            let f: &F = &*(f as *const F);
            f(VideoDecoder::from_glib_borrow(this).unsafe_cast_ref())
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"notify::min-force-key-unit-interval\0".as_ptr() as *const _,
                Some(std::mem::transmute::<_, unsafe extern "C" fn()>(
                    notify_min_force_key_unit_interval_trampoline::<Self, F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }

    #[cfg(feature = "v1_18")]
    #[cfg_attr(docsrs, doc(cfg(feature = "v1_18")))]
    #[doc(alias = "qos")]
    fn connect_qos_notify<F: Fn(&Self) + Send + Sync + 'static>(&self, f: F) -> SignalHandlerId {
        unsafe extern "C" fn notify_qos_trampoline<
            P: IsA<VideoDecoder>,
            F: Fn(&P) + Send + Sync + 'static,
        >(
            this: *mut ffi::GstVideoDecoder,
            _param_spec: glib::ffi::gpointer,
            f: glib::ffi::gpointer,
        ) {
            let f: &F = &*(f as *const F);
            f(VideoDecoder::from_glib_borrow(this).unsafe_cast_ref())
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"notify::qos\0".as_ptr() as *const _,
                Some(std::mem::transmute::<_, unsafe extern "C" fn()>(
                    notify_qos_trampoline::<Self, F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }
}

impl<O: IsA<VideoDecoder>> VideoDecoderExt for O {}