Enum ColorSpace 

pub enum ColorSpace {
    DeviceRGB,
    DeviceCMYK,
    DeviceGray,
    Indexed,
    Other(String),
}

Color-space tag attached to a PdfImageXObject.

PDF colour-space objects are richer than this enum — a real renderer needs to track ICC profiles, calibrated RGB, lab, etc. — but for JPEG passthrough we only need to surface the four most common families a JPEG can claim to be in (the JPEG payload itself dictates whether it’s 1-channel grayscale, 3-channel YCbCr→RGB, or 4-channel CMYK; the PDF /ColorSpace is a hint to the JPEG decoder about how the channels should be re-interpreted on the page).

Indexed is the special case where the PDF wraps a JPEG (which is itself grayscale or RGB) inside an indexed color space — it’s vanishingly rare with DCTDecode, but we surface the variant so downstream code can detect + special-case it.

Variants

DeviceRGB

/DeviceRGB — 3 channels, non-calibrated RGB.

DeviceCMYK

/DeviceCMYK — 4 channels, non-calibrated CMYK. JPEGs in CMYK are common in prepress workflows; the JPEG decoder needs to know not to apply YCbCr→RGB on the 4-channel form.

DeviceGray

/DeviceGray — 1 channel, non-calibrated grayscale.

Indexed

[/Indexed <base> <hival> <lookup>] — palette-based color space. The JPEG payload is itself either gray or RGB; the indexed wrapper applies on the PDF side.

Other(String)

Anything else (ICCBased, CalGray, CalRGB, Lab, Pattern, Separation, DeviceN, …). The JPEG bytes are still valid; the caller may need to consult an ICC profile to render the page accurately.

Trait Implementations

impl Clone for ColorSpace

fn clone(&self) -> ColorSpace

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ColorSpace

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

Formats the value using the given formatter.

impl Eq for ColorSpace

impl PartialEq for ColorSpace

fn eq(&self, other: &ColorSpace) -> 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 StructuralPartialEq for ColorSpace