Enum opencv::imgcodecs::ImwritePNGFlags

#[repr(C)]
pub enum ImwritePNGFlags {
    IMWRITE_PNG_STRATEGY_DEFAULT = 0,
    IMWRITE_PNG_STRATEGY_FILTERED = 1,
    IMWRITE_PNG_STRATEGY_HUFFMAN_ONLY = 2,
    IMWRITE_PNG_STRATEGY_RLE = 3,
    IMWRITE_PNG_STRATEGY_FIXED = 4,
}

Imwrite PNG specific flags used to tune the compression algorithm. These flags will be modify the way of PNG image compression and will be passed to the underlying zlib processing stage.

• The effect of IMWRITE_PNG_STRATEGY_FILTERED is to force more Huffman coding and less string matching; it is somewhat intermediate between IMWRITE_PNG_STRATEGY_DEFAULT and IMWRITE_PNG_STRATEGY_HUFFMAN_ONLY.
• IMWRITE_PNG_STRATEGY_RLE is designed to be almost as fast as IMWRITE_PNG_STRATEGY_HUFFMAN_ONLY, but give better compression for PNG image data.
• The strategy parameter only affects the compression ratio but not the correctness of the compressed output even if it is not set appropriately.
• IMWRITE_PNG_STRATEGY_FIXED prevents the use of dynamic Huffman codes, allowing for a simpler decoder for special applications.

Variants

IMWRITE_PNG_STRATEGY_DEFAULT = 0

Use this value for normal data.

IMWRITE_PNG_STRATEGY_FILTERED = 1

Use this value for data produced by a filter (or predictor).Filtered data consists mostly of small values with a somewhat random distribution. In this case, the compression algorithm is tuned to compress them better.

IMWRITE_PNG_STRATEGY_HUFFMAN_ONLY = 2

Use this value to force Huffman encoding only (no string match).

IMWRITE_PNG_STRATEGY_RLE = 3

Use this value to limit match distances to one (run-length encoding).

IMWRITE_PNG_STRATEGY_FIXED = 4

Using this value prevents the use of dynamic Huffman codes, allowing for a simpler decoder for special applications.

Trait Implementations

impl Clone for ImwritePNGFlags

fn clone(&self) -> ImwritePNGFlags

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ImwritePNGFlags

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

Formats the value using the given formatter.

impl From<ImwritePNGFlags> for i32

fn from(v: ImwritePNGFlags) -> Self

Converts to this type from the input type.

impl PartialEq for ImwritePNGFlags

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

This method tests for self and other values to be equal, and is used by ==.

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

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

impl TryFrom<i32> for ImwritePNGFlags

type Error = Error

The type returned in the event of a conversion error.

fn try_from(value: i32) -> Result<Self, Self::Error>

Performs the conversion.

impl Copy for ImwritePNGFlags

impl Eq for ImwritePNGFlags

impl StructuralPartialEq for ImwritePNGFlags