pub struct ImageFormatConstraints {Show 23 fields
pub pixel_format: PixelFormat,
pub color_spaces_count: u32,
pub color_space: [ColorSpace; 32],
pub min_coded_width: u32,
pub max_coded_width: u32,
pub min_coded_height: u32,
pub max_coded_height: u32,
pub min_bytes_per_row: u32,
pub max_bytes_per_row: u32,
pub max_coded_width_times_coded_height: u32,
pub layers: u32,
pub coded_width_divisor: u32,
pub coded_height_divisor: u32,
pub bytes_per_row_divisor: u32,
pub start_offset_divisor: u32,
pub display_width_divisor: u32,
pub display_height_divisor: u32,
pub required_min_coded_width: u32,
pub required_max_coded_width: u32,
pub required_min_coded_height: u32,
pub required_max_coded_height: u32,
pub required_min_bytes_per_row: u32,
pub required_max_bytes_per_row: u32,
}
Expand description
Describes constraints on layout of image data in buffers.
This type is deprecated for new code, but is still used by some camera code.
Fields§
§pixel_format: PixelFormat
The PixelFormat for which the following constraints apply. A participant may have more than one PixelFormat that’s supported, in which case that participant can use a list of ImageFormatConstraints with an entry per PixelFormat. It’s not uncommon for the other fields of ImageFormatConstraints to vary by PixelFormat - for example for a linear format to support smaller max size than a tiled format.
color_spaces_count: u32
Empty is an error. Redundant entries are an error. Arbitrary ordering is not an error.
color_space: [ColorSpace; 32]
§min_coded_width: u32
Minimum permitted width in pixels.
For example a video decoder participant may set this field to the minimum coded_width that might potentially be specified by a stream. In contrast, required_min_coded_width would be set to the current coded_width specified by the stream. While min_coded_width aggregates by taking the max, required_min_coded_width aggregates by taking the min.
See also required_min_coded_width.
max_coded_width: u32
Maximum width in pixels. For example Scenic may set this field (directly or via sub-participants) to the maximum width that can be composited. 0 is treated as 0xFFFFFFFF.
min_coded_height: u32
Minimum height in pixels. For example a video decoder participant may set this field to the coded_height specified by a stream.
max_coded_height: u32
Maximum height in pixels. For example Scenic may set this field (directly or via sub-participants) to the maximum height that can be composited. 0 is treated as 0xFFFFFFFF.
min_bytes_per_row: u32
Must be >= the value implied by min_coded_width for plane 0.
max_bytes_per_row: u32
Must be >= the value implied by max_coded_width for plane 0. 0 is treated as 0xFFFFFFFF.
max_coded_width_times_coded_height: u32
The max image area in pixels is limited indirectly via BufferSettings.size_bytes, and can also be enforced directly via this field. 0 is treated as 0xFFFFFFFF.
layers: u32
Number of layers within a multi-layered image. 0 is treated as 1.
coded_width_divisor: u32
coded_width % width_divisor must be 0. 0 is treated as 1.
coded_height_divisor: u32
coded_height % height_divisor must be 0. 0 is treated as 1.
bytes_per_row_divisor: u32
bytes_per_row % bytes_per_row_divisor must be 0. 0 is treated as 1.
start_offset_divisor: u32
vmo_usable_start % start_offset_divisor must be 0. 0 is treated as 1.
display_width_divisor: u32
display_width % display_width_divisor must be 0. 0 is treated as 1.
display_height_divisor: u32
display_height % display_height_divisor must be 0. 0 is treated as 1.
required_min_coded_width: u32
required_ dimension bounds.
In contrast to the corresponding fields without “required_” at the start, these fields (when set to non-zero values) express a requirement that the resulting aggregated non-required_ fields specify a space that fully contain the space expressed by each participant’s required_ fields.
For example, a producer video decoder is perfectly happy for the consumer to be willing to accept anything, and the video decoder doesn’t really want to constrain the potential space of dimensions that might be seen in a stream and may be acceptable to the consumer, but the video decoder needs to ensure that the resulting dimension ranges contain at least the current dimensions decoded from the stream.
Similarly, an initiator with a particular dynamic-dimension scenario in mind may wish to require up front that participants agree to handle at least the range of dimensions expected by the initiator in that scenario (else fail earlier rather than later, maybe trying again with smaller required_ space).
It’s much more common for a producer or initiator to set these fields than for a consumer to set these fields.
While the non-required_ fields aggregate by taking the intersection, the required_ fields aggregate by taking the union.
If set, the required_max_coded_width and required_max_coded_height will cause the allocated buffers to be large enough to hold an image that is required_max_coded_width * required_max_coded_height.
TODO(dustingreen): Make it easier to allocate buffers of minimal size that can (optionally) also handle 90 degree rotated version of the max dimensions / alternate required bounds for another main aspect ratio. 0 is treated as 0xFFFFFFFF.
required_max_coded_width: u32
§required_min_coded_height: u32
0 is treated as 0xFFFFFFFF.
required_max_coded_height: u32
§required_min_bytes_per_row: u32
0 is treated as 0xFFFFFFFF.
required_max_bytes_per_row: u32
Trait Implementations§
source§impl Clone for ImageFormatConstraints
impl Clone for ImageFormatConstraints
source§fn clone(&self) -> ImageFormatConstraints
fn clone(&self) -> ImageFormatConstraints
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for ImageFormatConstraints
impl Debug for ImageFormatConstraints
source§impl Decode<ImageFormatConstraints> for ImageFormatConstraints
impl Decode<ImageFormatConstraints> for ImageFormatConstraints
source§impl Encode<ImageFormatConstraints> for &ImageFormatConstraints
impl Encode<ImageFormatConstraints> for &ImageFormatConstraints
source§impl<T0: Encode<PixelFormat>, T1: Encode<u32>, T2: Encode<Array<ColorSpace, 32>>, T3: Encode<u32>, T4: Encode<u32>, T5: Encode<u32>, T6: Encode<u32>, T7: Encode<u32>, T8: Encode<u32>, T9: Encode<u32>, T10: Encode<u32>, T11: Encode<u32>, T12: Encode<u32>, T13: Encode<u32>, T14: Encode<u32>, T15: Encode<u32>, T16: Encode<u32>, T17: Encode<u32>, T18: Encode<u32>, T19: Encode<u32>, T20: Encode<u32>, T21: Encode<u32>, T22: Encode<u32>> Encode<ImageFormatConstraints> for (T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13, T14, T15, T16, T17, T18, T19, T20, T21, T22)
impl<T0: Encode<PixelFormat>, T1: Encode<u32>, T2: Encode<Array<ColorSpace, 32>>, T3: Encode<u32>, T4: Encode<u32>, T5: Encode<u32>, T6: Encode<u32>, T7: Encode<u32>, T8: Encode<u32>, T9: Encode<u32>, T10: Encode<u32>, T11: Encode<u32>, T12: Encode<u32>, T13: Encode<u32>, T14: Encode<u32>, T15: Encode<u32>, T16: Encode<u32>, T17: Encode<u32>, T18: Encode<u32>, T19: Encode<u32>, T20: Encode<u32>, T21: Encode<u32>, T22: Encode<u32>> Encode<ImageFormatConstraints> for (T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13, T14, T15, T16, T17, T18, T19, T20, T21, T22)
source§impl Hash for ImageFormatConstraints
impl Hash for ImageFormatConstraints
source§impl Ord for ImageFormatConstraints
impl Ord for ImageFormatConstraints
source§fn cmp(&self, other: &ImageFormatConstraints) -> Ordering
fn cmp(&self, other: &ImageFormatConstraints) -> Ordering
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere
Self: Sized,
source§impl PartialEq for ImageFormatConstraints
impl PartialEq for ImageFormatConstraints
source§fn eq(&self, other: &ImageFormatConstraints) -> bool
fn eq(&self, other: &ImageFormatConstraints) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl PartialOrd for ImageFormatConstraints
impl PartialOrd for ImageFormatConstraints
source§fn partial_cmp(&self, other: &ImageFormatConstraints) -> Option<Ordering>
fn partial_cmp(&self, other: &ImageFormatConstraints) -> Option<Ordering>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl TypeMarker for ImageFormatConstraints
impl TypeMarker for ImageFormatConstraints
§type Owned = ImageFormatConstraints
type Owned = ImageFormatConstraints
source§fn inline_align(_context: Context) -> usize
fn inline_align(_context: Context) -> usize
source§fn inline_size(_context: Context) -> usize
fn inline_size(_context: Context) -> usize
inline_align
.§fn encode_is_copy() -> bool
fn encode_is_copy() -> bool
Self::Owned
matches the FIDL wire
format and encoding requires no validation. When true, we can optimize
encoding arrays and vectors of Self::Owned
to a single memcpy. Read more§fn decode_is_copy() -> bool
fn decode_is_copy() -> bool
Self::Owned
matches the FIDL wire
format and decoding requires no validation. When true, we can optimize
decoding arrays and vectors of Self::Owned
to a single memcpy.source§impl ValueTypeMarker for ImageFormatConstraints
impl ValueTypeMarker for ImageFormatConstraints
§type Borrowed<'a> = &'a ImageFormatConstraints
type Borrowed<'a> = &'a ImageFormatConstraints
Encode<Self>
type cheaply obtainable from &Self::Owned
. There are three cases: Read moreimpl Copy for ImageFormatConstraints
impl Eq for ImageFormatConstraints
impl Persistable for ImageFormatConstraints
impl StructuralPartialEq for ImageFormatConstraints
Auto Trait Implementations§
impl Freeze for ImageFormatConstraints
impl RefUnwindSafe for ImageFormatConstraints
impl Send for ImageFormatConstraints
impl Sync for ImageFormatConstraints
impl Unpin for ImageFormatConstraints
impl UnwindSafe for ImageFormatConstraints
Blanket Implementations§
§impl<T> Body for Twhere
T: Persistable,
impl<T> Body for Twhere
T: Persistable,
§type MarkerAtTopLevel = T
type MarkerAtTopLevel = T
§type MarkerInResultUnion = T
type MarkerInResultUnion = T
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
source§impl<T> CloneToUninit for Twhere
T: Clone,
impl<T> CloneToUninit for Twhere
T: Clone,
source§default unsafe fn clone_to_uninit(&self, dst: *mut T)
default unsafe fn clone_to_uninit(&self, dst: *mut T)
clone_to_uninit
)source§impl<T> CloneToUninit for Twhere
T: Copy,
impl<T> CloneToUninit for Twhere
T: Copy,
source§unsafe fn clone_to_uninit(&self, dst: *mut T)
unsafe fn clone_to_uninit(&self, dst: *mut T)
clone_to_uninit
)