Trait opencv::core::FileStorageTrait

pub trait FileStorageTrait {
    fn as_raw_FileStorage(&self) -> *const c_void;
    fn as_raw_mut_FileStorage(&mut self) -> *mut c_void;

    fn state(&self) -> i32 { ... }
    fn set_state(&mut self, val: i32) { ... }
    fn elname(&self) -> String { ... }
    fn set_elname(&mut self, val: &str) { ... }
    fn open(
        &mut self, 
        filename: &str, 
        flags: i32, 
        encoding: &str
    ) -> Result<bool> { ... }
    fn is_opened(&self) -> Result<bool> { ... }
    fn release(&mut self) -> Result<()> { ... }
    fn release_and_get_string(&mut self) -> Result<String> { ... }
    fn get_first_top_level_node(&self) -> Result<FileNode> { ... }
    fn root(&self, streamidx: i32) -> Result<FileNode> { ... }
    fn get(&self, nodename: &str) -> Result<FileNode> { ... }
    fn get_node(&self, nodename: &str) -> Result<FileNode> { ... }
    fn write_i32(&mut self, name: &str, val: i32) -> Result<()> { ... }
    fn write_f64(&mut self, name: &str, val: f64) -> Result<()> { ... }
    fn write_str(&mut self, name: &str, val: &str) -> Result<()> { ... }
    fn write_mat(&mut self, name: &str, val: &Mat) -> Result<()> { ... }
    fn write_str_vec(&mut self, name: &str, val: &Vector<String>) -> Result<()> { ... }
    fn write_raw(
        &mut self, 
        fmt: &str, 
        vec: *const c_void, 
        len: size_t
    ) -> Result<()> { ... }
    fn write_comment(&mut self, comment: &str, append: bool) -> Result<()> { ... }
    fn start_write_struct(
        &mut self, 
        name: &str, 
        flags: i32, 
        type_name: &str
    ) -> Result<()> { ... }
    fn end_write_struct(&mut self) -> Result<()> { ... }
    fn get_format(&self) -> Result<i32> { ... }
}

XML/YAML/JSON file storage class that encapsulates all the information necessary for writing or reading data to/from a file.

Required methods

fn as_raw_FileStorage(&self) -> *const c_void

fn as_raw_mut_FileStorage(&mut self) -> *mut c_void

Provided methods

fn state(&self) -> i32

fn set_state(&mut self, val: i32)

fn elname(&self) -> String

fn set_elname(&mut self, val: &str)

fn open(&mut self, filename: &str, flags: i32, encoding: &str) -> Result<bool>

Opens a file.

See description of parameters in FileStorage::FileStorage. The method calls FileStorage::release before opening the file.

Parameters

• filename: Name of the file to open or the text string to read the data from. Extension of the file (.xml, .yml/.yaml or .json) determines its format (XML, YAML or JSON respectively). Also you can append .gz to work with compressed files, for example myHugeMatrix.xml.gz. If both FileStorage::WRITE and FileStorage::MEMORY flags are specified, source is used just to specify the output file format (e.g. mydata.xml, .yml etc.). A file name can also contain parameters. You can use this format, “*?base64” (e.g. “file.json?base64” (case sensitive)), as an alternative to FileStorage::BASE64 flag.
• flags: Mode of operation. One of FileStorage::Mode
• encoding: Encoding of the file. Note that UTF-16 XML encoding is not supported currently and you should use 8-bit encoding instead of it.

C++ default parameters

• encoding: String()

fn is_opened(&self) -> Result<bool>

Checks whether the file is opened.

Returns

true if the object is associated with the current file and false otherwise. It is a good practice to call this method after you tried to open a file.

fn release(&mut self) -> Result<()>

Closes the file and releases all the memory buffers.

Call this method after all I/O operations with the storage are finished.

fn release_and_get_string(&mut self) -> Result<String>

Closes the file and releases all the memory buffers.

Call this method after all I/O operations with the storage are finished. If the storage was opened for writing data and FileStorage::WRITE was specified

fn get_first_top_level_node(&self) -> Result<FileNode>

Returns the first element of the top-level mapping.

Returns

The first element of the top-level mapping.

fn root(&self, streamidx: i32) -> Result<FileNode>

Returns the top-level mapping

Parameters

• streamidx: Zero-based index of the stream. In most cases there is only one stream in the file. However, YAML supports multiple streams and so there can be several.

Returns

The top-level mapping.

C++ default parameters

• streamidx: 0

fn get(&self, nodename: &str) -> Result<FileNode>

Returns the specified element of the top-level mapping.

Parameters

• nodename: Name of the file node.

Returns

Node with the given name.

fn get_node(&self, nodename: &str) -> Result<FileNode>

Returns the specified element of the top-level mapping.

Parameters

• nodename: Name of the file node.

Returns

Node with the given name.

Overloaded parameters

fn write_i32(&mut self, name: &str, val: i32) -> Result<()>

Simplified writing API to use with bindings.

Parameters

• name: Name of the written object. When writing to sequences (a.k.a. “arrays”), pass an empty string.
• val: Value of the written object.

fn write_f64(&mut self, name: &str, val: f64) -> Result<()>

Simplified writing API to use with bindings.

Parameters

• name: Name of the written object. When writing to sequences (a.k.a. “arrays”), pass an empty string.
• val: Value of the written object.

Overloaded parameters

fn write_str(&mut self, name: &str, val: &str) -> Result<()>

Simplified writing API to use with bindings.

Parameters

• name: Name of the written object. When writing to sequences (a.k.a. “arrays”), pass an empty string.
• val: Value of the written object.

Overloaded parameters

fn write_mat(&mut self, name: &str, val: &Mat) -> Result<()>

Simplified writing API to use with bindings.

Parameters

• name: Name of the written object. When writing to sequences (a.k.a. “arrays”), pass an empty string.
• val: Value of the written object.

Overloaded parameters

fn write_str_vec(&mut self, name: &str, val: &Vector<String>) -> Result<()>

Simplified writing API to use with bindings.

Parameters

• name: Name of the written object. When writing to sequences (a.k.a. “arrays”), pass an empty string.
• val: Value of the written object.

Overloaded parameters

fn write_raw(
    &mut self,
    fmt: &str,
    vec: *const c_void,
    len: size_t
) -> Result<()>

Writes multiple numbers.

Writes one or more numbers of the specified format to the currently written structure. Usually it is more convenient to use operator << instead of this method.

Parameters

• fmt: Specification of each array element, see @ref format_spec “format specification”
• vec: Pointer to the written array.
• len: Number of the uchar elements to write.

fn write_comment(&mut self, comment: &str, append: bool) -> Result<()>

Writes a comment.

The function writes a comment into file storage. The comments are skipped when the storage is read.

Parameters

• comment: The written comment, single-line or multi-line
• append: If true, the function tries to put the comment at the end of current line. Else if the comment is multi-line, or if it does not fit at the end of the current line, the comment starts a new line.

C++ default parameters

• append: false

fn start_write_struct(
    &mut self,
    name: &str,
    flags: i32,
    type_name: &str
) -> Result<()>

Starts to write a nested structure (sequence or a mapping).

Parameters

• name: name of the structure. When writing to sequences (a.k.a. “arrays”), pass an empty string.
• flags: type of the structure (FileNode::MAP or FileNode::SEQ (both with optional FileNode::FLOW)).
• typeName: optional name of the type you store. The effect of setting this depends on the storage format. I.e. if the format has a specification for storing type information, this parameter is used.

C++ default parameters

• type_name: String()

fn end_write_struct(&mut self) -> Result<()>

Finishes writing nested structure (should pair startWriteStruct())

fn get_format(&self) -> Result<i32>

Returns the current format.

Returns

The current format, see FileStorage::Mode

Implementors

impl FileStorageTrait for FileStorage

impl FileStorageTrait for PtrOfFileStorage