Enum WriterError 

#[non_exhaustive]
pub enum WriterError {
    InvalidDimensions {
        width: u32,
        height: u32,
    },
    UnknownPixelFormat(String),
    HardwarePixelFormat(String),
    InvalidFps {
        num: i32,
        den: i32,
    },
    ZeroQueueCapacity,
    NoVideoDestination,
    FilterShape {
        input_pads: usize,
        video_input_pads: usize,
        output_pads: usize,
        video_output_pads: usize,
    },
    ConflictingFilterDescriptions,
    DisconnectedFilterGraph {
        components: usize,
    },
    UnreachableFilterOutput,
    StreamMapsUnsupported,
}

Errors raised while validating a VideoWriterBuilder or opening its pipeline. Reachable through crate::error::Error::Writer; it is exported from crate::error rather than the crate root to keep the root surface to the three settled writer types.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

InvalidDimensions

Width or height is zero or exceeds i32::MAX.

Fields

width: u32

height: u32

UnknownPixelFormat(String)

The pixel-format name is not known to av_get_pix_fmt.

HardwarePixelFormat(String)

A hardware pixel format (e.g. cuda, vaapi) cannot be filled from a CPU byte buffer.

InvalidFps

fps(num, den) had a non-positive component.

Fields

num: i32

den: i32

ZeroQueueCapacity

queue_capacity(0) was requested.

NoVideoDestination

The built pipeline consumes no video from the pushed frames (a disable_video() output). Without this check write would block forever against a live-but-unconsumed receiver.

FilterShape

The filter_desc graph does not consume exactly one video input and produce exactly one video output. A second input pad would have no producer (the pipeline would buffer forever waiting for it) and a second output pad would have no destination.

Fields

input_pads: usize

video_input_pads: usize

output_pads: usize

video_output_pads: usize

ConflictingFilterDescriptions

Both VideoWriterBuilder::filter_desc and the opened Output’s set_video_filter were configured. The writer runs exactly one filter chain between the pushed frames and the encoder, and guessing which of the two the caller meant would silently ignore the other — configure the chain in exactly one place.

DisconnectedFilterGraph

The filter_desc parses into more than one disconnected filter component (e.g. "nullsink;color=..."). The pushed frames would feed one part while an unrelated part feeds (or starves) the encoder — an unbounded side source could even keep the job from ever finishing.

Fields

components: usize

UnreachableFilterOutput

The filter_desc is connected, but no directed path leads from its input pad to its output pad (e.g. "color,split[out][aux];[aux][in]overlay,nullsink"): the pushed frames drain into a sink while an unrelated branch feeds the encoder, so they could never influence the encoded output — and an unbounded side source would keep the job from ever finishing.

This check is STRUCTURAL: it follows the links between filters, and inside each filter every input pad is assumed to influence every output pad. Filter routing is not pruned by the applied options, because libavfilter routing is not static — a selector’s map (streamselect) can be rewritten mid-stream by sendcmd or the send-command API, and ffmpeg itself accepts and runs descriptions whose current selection drops the pushed stream. A description that discards the pushed frames at runtime (an unselected streamselect input, a multi-stream concat steering them into a sink leg, …) therefore passes this gate and runs as declared, exactly like the CLI; what cannot pass is a graph where no wiring could ever carry the pushed frames toward the encoder.

StreamMapsUnsupported

The Output carries stream maps (add_stream_map / add_stream_map_with_copy). The writer’s single video stream is the only stream there is, so maps have nothing to select; rejecting them beats silently ignoring them.

Trait Implementations

impl Debug for WriterError

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

Formats the value using the given formatter.

impl Display for WriterError

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

Formats the value using the given formatter.

impl Error for WriterError

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

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

Provides type-based access to context intended for error reports.

impl From<WriterError> for Error

fn from(source: WriterError) -> Self

Converts to this type from the input type.