Struct Options 

pub struct Options {
    pub level: Compression,
    pub width: u32,
    pub height: u32,
    pub depth: u8,
    pub format: ColorFormat,
    pub buffer: usize,
}

Image properties and compression options.

Fields

level: Compression

The compression level.

width: u32

The width of the image, in pixels.

height: u32

The height of the image, in pixels.

depth: u8

The number of bits in each channel.

format: ColorFormat

The format of the image.

buffer: usize

The size of the compressed data buffer.

This value determines the maximum size of an IDAT chunk.

Implementations

impl Options

pub fn smallest(width: u32, height: u32) -> Self

Specifies an 8-bit RGBA image optimizing for image size.

Examples found in repository

examples/flag.rs (line 9)

fn main() {
    let mut enc = Options::smallest(480, 360)
        .build(File::create("flag.png").unwrap())
        .unwrap();

    meta::text(
        &mut enc,
        meta::Keyword::Author,
        "Ram Kaniyur",
    ).unwrap();

    let mut row = [255; 480 * 4];

    for x in 0..480 {
        let i = x * 4;

        if x < 160 {
            row[i] = 0;
        } else if x < 320 {
            row[i + 1] = 0;
        } else {
            row[i + 2] = 0;
        }
    }

    for _y in 0..360 {
        enc.write(&row).unwrap();
    }

    enc.finish().unwrap();
}

pub fn fastest(width: u32, height: u32) -> Self

Specifies an 8-bit RGBA image optimizing for encoding speed.

pub fn build<W>(&self, sink: W) -> Result<Encoder<W, Standard>>

where W: Write,

Make a new encoder with these options and the default filter.

To customize the filter as well, see Encoder::new.

Examples found in repository

examples/flag.rs (line 10)

fn main() {
    let mut enc = Options::smallest(480, 360)
        .build(File::create("flag.png").unwrap())
        .unwrap();

    meta::text(
        &mut enc,
        meta::Keyword::Author,
        "Ram Kaniyur",
    ).unwrap();

    let mut row = [255; 480 * 4];

    for x in 0..480 {
        let i = x * 4;

        if x < 160 {
            row[i] = 0;
        } else if x < 320 {
            row[i + 1] = 0;
        } else {
            row[i + 2] = 0;
        }
    }

    for _y in 0..360 {
        enc.write(&row).unwrap();
    }

    enc.finish().unwrap();
}

pub fn stride(&self) -> usize

The number of bytes occupied by a single row of the uncompressed image.

Trait Implementations

impl Debug for Options

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

Formats the value using the given formatter.

impl<'a> From<&'a Options> for None

fn from(_: &Options) -> Self

Converts to this type from the input type.

impl<'a> From<&'a Options> for Standard

fn from(opts: &Options) -> Self

Converts to this type from the input type.