ArImageMetadata

Provides access to CPU image camera metadata.

Summary

Typedefs

 ArImageMetadata

typedef

struct ArImageMetadata_

Camera capture metadata ( reference type, large data ).

 ArImageMetadata_const_entry

typedef

struct ArImageMetadata_const_entry

Defines a single read-only image metadata entry.

 ArImageMetadata_rational

typedef

struct ArImageMetadata_rational

Defines a rational data type in

 ArImageMetadata_const_entry

Functions

 ArImageMetadata_getAllKeys 
(const ArSession 
*session, const ArImageMetadata 
*image_metadata, int32_t *out_number_of_tags, const uint32_t **out_tags)

void

Retrieves the list of the supported image metadata tags that can be queried for their value.

 ArImageMetadata_getConstEntry 
(const ArSession 
*session, const ArImageMetadata 
*image_metadata, uint32_t tag, ArImageMetadata_const_entry 
*out_metadata_entry)

 ArStatus

Get a metadata entry for the provided

 ArImageMetadata

and tag.

 ArImageMetadata_release 
( ArImageMetadata 
*metadata)

void

Releases a reference to the metadata.

Structs

ArImageMetadata_const_entry

Defines a single read-only image metadata entry.

ArImageMetadata_rational

Defines a rational data type in ArImageMetadata_const_entry .

Typedefs

ArImageMetadata

struct ArImageMetadata_ ArImageMetadata

Camera capture metadata ( reference type, large data ).

Acquire with: ArFrame_acquireImageMetadata
Release with: ArImageMetadata_release

ArImageMetadata_const_entry

 struct 
  
  ArImageMetadata_const_entry 
 
  
 ArImageMetadata_const_entry

Defines a single read-only image metadata entry.

Struct matches ACameraMetadata_const_entry in Android NDK r21.

ArImageMetadata_rational

struct ArImageMetadata_rational 
ArImageMetadata_rational

Defines a rational data type in ArImageMetadata_const_entry .

Struct matches ACameraMetadata_rational in Android NDK r21.

Functions

ArImageMetadata_getAllKeys

 void 
  
 ArImageMetadata_getAllKeys 
 ( 
  
 const 
  
  ArSession 
 
  
 * 
 session 
 , 
  
 const 
  
  ArImageMetadata 
 
  
 * 
 image_metadata 
 , 
  
 int32_t 
  
 * 
 out_number_of_tags 
 , 
  
 const 
  
 uint32_t 
  
 ** 
 out_tags 
 )

Retrieves the list of the supported image metadata tags that can be queried for their value.

The out_tags list remains valid until image_metadata is released via ArImageMetadata_release .

Details

Parameters

`session`	The ARCore session.
`image_metadata`	`ArImageMetadata` struct obtained from `ArFrame_acquireImageMetadata` .
`out_number_of_tags`	Number of metadata tags returned in the list.
`out_tags`	The data pointer to the beginning of the list of `uint32_t` tags.

ArImageMetadata_getConstEntry

  ArStatus 
 
  
 ArImageMetadata_getConstEntry 
 ( 
  
 const 
  
  ArSession 
 
  
 * 
 session 
 , 
  
 const 
  
  ArImageMetadata 
 
  
 * 
 image_metadata 
 , 
  
 uint32_t 
  
 tag 
 , 
  
  ArImageMetadata_const_entry 
 
  
 * 
 out_metadata_entry 
 )

Get a metadata entry for the provided ArImageMetadata and tag.

The returned out_metadata_entry remains valid until the provided image_metadata is released via ArImageMetadata_release .

Details

Parameters

`session`	The ARCore session.
`image_metadata`	`ArImageMetadata` struct obtained from `ArFrame_acquireImageMetadata` .
`tag`	The desired `uint32_t` metadata tag to be retrieved from the provided `ArImageMetadata` struct.
`out_metadata_entry`	The `ArImageMetadata_const_entry` struct to which the metadata tag data should be written to, updated only when function returns `AR_SUCCESS` .

Returns

 AR_SUCCESS

or any of:

AR_ERROR_INVALID_ARGUMENT - if either session , image_metadata or out_metadata_entry is null.
AR_ERROR_METADATA_NOT_FOUND - if image_metadata does not contain an entry of the tag value.

ArImageMetadata_release

void ArImageMetadata_release( ArImageMetadata 
*metadata
)

Releases a reference to the metadata.

This must match a call to ArFrame_acquireImageMetadata .

This function may safely be called with NULL - it will do nothing.