Struct CMFormatDescription 

pub struct CMFormatDescription { /* private fields */ }

Available on crate feature CMFormatDescription only.

A reference to a CMFormatDescription, a CF object describing media of a particular type (audio, video, muxed, etc).

See also Apple’s documentation

Implementations

impl CMFormatDescription

pub unsafe fn create( allocator: Option<&CFAllocator>, media_type: CMMediaType, media_sub_type: u32, extensions: Option<&CFDictionary>, format_description_out: NonNull<*const CMFormatDescription>, ) -> i32

Creates a generic CMFormatDescription object.

Use this call to create any CMFormatDescription that is composed solely of extensions, and for which CFEqual() of a the extensions dictionaries is a valid test for Format Description equality. Note that for some media types using this routine may result in creating a format description that is not fully specified for the purpose of media processing. Whenever possible, use media-specific format description creations routines such as CMVideoFormatDescriptionCreate, CMAudioFormatDescriptionCreate, etc.

Returns: A new CMFormatDescription object.

Safety

• extensions generics must be of the correct type.
• format_description_out must be a valid pointer.

impl CMFormatDescription

pub unsafe fn equal( format_description: Option<&CMFormatDescription>, other_format_description: Option<&CMFormatDescription>, ) -> bool

Compares two CMFormatDescription objects for equality.

This calls CFEqual on the provided CMFormatDescription objects. In contrast to the CF call it is NULL safe.

pub unsafe fn equal_ignoring_extension_keys( format_description: Option<&CMFormatDescription>, other_format_description: Option<&CMFormatDescription>, format_description_extension_keys_to_ignore: Option<&CFType>, sample_description_extension_atom_keys_to_ignore: Option<&CFType>, ) -> bool

Compares two CMFormatDescription objects for equality, ignoring differences in specified lists of format description extension keys and sample description extension keys.

This function is NULL safe. If any keys are passed, kCMFormatDescriptionExtension_VerbatimSampleDescription and kCMFormatDescriptionExtension_VerbatimISOSampleEntry will also be automatically ignored for the purpose of comparison.

Parameter formatDescriptionExtensionKeysToIgnore: Either a single format description extension key (CFString) or a CFArray of such keys.

Parameter sampleDescriptionExtensionAtomKeysToIgnore: Either a single sample description extension atom key (four-character CFString) or a CFArray of such keys. See kCMFormatDescriptionExtension_SampleDescriptionExtensionAtoms.

Safety

• format_description_extension_keys_to_ignore should be of the correct type.
• sample_description_extension_atom_keys_to_ignore should be of the correct type.

pub unsafe fn media_type(&self) -> CMMediaType

Returns the media type of a CMFormatDescription.

For example, returns kCMMediaType_Audio for a description of an audio stream.

Returns: The media type of the CMFormatDescription.

pub unsafe fn media_sub_type(&self) -> u32

Returns the media subtype of a CMFormatDescription.

The media subtype is defined in a media-specific way. For audio streams, the media subtype is the asbd.mFormatID. For video streams, the media subtype is the video codec type. For muxed streams, it is the format of the muxed stream. For example, ’aac ’ is returned for a description of an AAC audio stream, ‘avc1’ is returned for a description of an H.264 video stream, and ‘mp2t’ is returned for a description of an MPEG-2 transport (muxed) stream. If a particular type of media stream does not have subtypes, this API may return 0.

Returns: The media subtype of the CMFormatDescription.

pub unsafe fn extensions(&self) -> Option<CFRetained<CFDictionary>>

Returns an immutable dictionary containing all the extensions of a CMFormatDescription.

If there are no extensions, NULL is returned. Extensions dictionaries are valid property list objects. This means that dictionary keys are all CFStrings, and the values are all either CFNumber, CFString, CFBoolean, CFArray, CFDictionary, CFDate, or CFData. The returned dictionary is not retained by this call, so clients are required to retain it if they need to keep it longer.

Returns: An immutable dictionary containing all the extensions of the CMFormatDescription. May be NULL.

impl CMFormatDescription

pub unsafe fn extension( &self, extension_key: &CFString, ) -> Option<CFRetained<CFPropertyList>>

Returns the specified extension of a CMFormatDescription.

If the named extension does not exist, NULL is returned. The extension is always a valid property list object. This means that it will be either a CFNumber, CFString, CFBoolean, CFArray, CFDictionary, CFDate, or CFData. If it is a CFDictionary, the keys will all be CFStrings. The returned extension is not retained by this call, so it is only valid as long as the CMFormatDescription is valid. Clients are required to retain it if they need to keep it longer.

Returns: The specified extension of the CMFormatDescription. May be NULL.

Methods from Deref<Target = CFType>

pub fn downcast_ref<T>(&self) -> Option<&T>

where T: ConcreteType,

Available on crate feature CMAttachment only.

Attempt to downcast the type to that of type T.

This is the reference-variant. Use CFRetained::downcast if you want to convert a retained type. See also ConcreteType for more details on which types support being converted to.

pub fn retain_count(&self) -> usize

Available on crate feature CMAttachment only.

Get the reference count of the object.

This function may be useful for debugging. You normally do not use this function otherwise.

Beware that some things (like CFNumbers, small CFStrings etc.) may not have a normal retain count for optimization purposes, and can return usize::MAX in that case.

Trait Implementations

impl AsRef<AnyObject> for CMFormatDescription

fn as_ref(&self) -> &AnyObject

Converts this type into a shared reference of the (usually inferred) input type.

impl AsRef<CFType> for CMFormatDescription

fn as_ref(&self) -> &CFType

Converts this type into a shared reference of the (usually inferred) input type.

impl AsRef<CMFormatDescription> for CMFormatDescription

fn as_ref(&self) -> &Self

Converts this type into a shared reference of the (usually inferred) input type.

impl Borrow<AnyObject> for CMFormatDescription

fn borrow(&self) -> &AnyObject

Immutably borrows from an owned value.

impl Borrow<CFType> for CMFormatDescription

fn borrow(&self) -> &CFType

Immutably borrows from an owned value.

impl ConcreteType for CMFormatDescription

fn type_id() -> CFTypeID

Returns the CFTypeID of CMFormatDescription objects.

You can check if a CFTypeRef object is actually a CMFormatDescription by comparing CFGetTypeID(object) with CMFormatDescriptionGetTypeID().

impl Debug for CMFormatDescription

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

Formats the value using the given formatter.

impl Deref for CMFormatDescription

type Target = CFType

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl Hash for CMFormatDescription

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, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Message for CMFormatDescription

fn retain(&self) -> Retained<Self>

where Self: Sized,

Increment the reference count of the receiver.

impl PartialEq for CMFormatDescription

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl RefEncode for CMFormatDescription

const ENCODING_REF: Encoding

The Objective-C type-encoding for a reference of this type.

impl Type for CMFormatDescription

fn retain(&self) -> CFRetained<Self>

where Self: Sized,

Increment the reference count of the receiver.

fn as_concrete_TypeRef(&self) -> &Self

👎Deprecated: this is redundant

Helper for easier transition from the core-foundation crate.

unsafe fn wrap_under_get_rule(ptr: *const Self) -> CFRetained<Self>

where Self: Sized,

👎Deprecated: use CFRetained::retain

Helper for easier transition from the core-foundation crate.

fn as_CFTypeRef(&self) -> &CFType

where Self: AsRef<CFType>,

👎Deprecated: this is redundant (CF types deref to CFType)

Helper for easier transition from the core-foundation crate.

unsafe fn wrap_under_create_rule(ptr: *const Self) -> CFRetained<Self>

where Self: Sized,

👎Deprecated: use CFRetained::from_raw

Helper for easier transition from the core-foundation crate.

impl Eq for CMFormatDescription

impl Send for CMFormatDescription

impl Sync for CMFormatDescription