A. Molzer
ac65bd8477
This makes the decode example capable of writing correct PAM images in many more cases, such as bilevel encoded (Fax3) masks.
86 lines
2.3 KiB
Rust
86 lines
2.3 KiB
Rust
//! Decoding and Encoding of TIFF Images
|
|
//!
|
|
//! TIFF (Tagged Image File Format) is a versatile image format that supports
|
|
//! lossless and lossy compression.
|
|
//!
|
|
//! # Related Links
|
|
//! * <https://web.archive.org/web/20210108073850/https://www.adobe.io/open/standards/TIFF.html> - The TIFF specification
|
|
|
|
mod bytecast;
|
|
pub mod decoder;
|
|
mod directory;
|
|
pub mod encoder;
|
|
mod error;
|
|
pub mod tags;
|
|
|
|
pub use self::directory::Directory;
|
|
pub use self::error::{TiffError, TiffFormatError, TiffResult, TiffUnsupportedError, UsageError};
|
|
|
|
/// An enumeration over supported color types and their bit depths
|
|
#[derive(Copy, PartialEq, Eq, Debug, Clone, Hash)]
|
|
#[non_exhaustive]
|
|
pub enum ColorType {
|
|
/// Pixel is grayscale
|
|
Gray(u8),
|
|
|
|
/// Pixel contains R, G and B channels
|
|
RGB(u8),
|
|
|
|
/// Pixel is an index into a color palette
|
|
Palette(u8),
|
|
|
|
/// Pixel is grayscale with an alpha channel
|
|
GrayA(u8),
|
|
|
|
/// Pixel is RGB with an alpha channel
|
|
RGBA(u8),
|
|
|
|
/// Pixel is CMYK
|
|
CMYK(u8),
|
|
|
|
/// Pixel is CMYK with an alpha channel
|
|
CMYKA(u8),
|
|
|
|
/// Pixel is YCbCr
|
|
YCbCr(u8),
|
|
|
|
/// Pixel is CIE L*a*b* (ICC LAb)
|
|
Lab(u8),
|
|
|
|
/// Pixel has multiple bands/channels
|
|
Multiband { bit_depth: u8, num_samples: u16 },
|
|
}
|
|
impl ColorType {
|
|
/// The number of bits used to store each sample.
|
|
pub fn bit_depth(&self) -> u8 {
|
|
match *self {
|
|
ColorType::Gray(b)
|
|
| ColorType::RGB(b)
|
|
| ColorType::Palette(b)
|
|
| ColorType::GrayA(b)
|
|
| ColorType::RGBA(b)
|
|
| ColorType::CMYK(b)
|
|
| ColorType::CMYKA(b)
|
|
| ColorType::YCbCr(b)
|
|
| ColorType::Lab(b)
|
|
| ColorType::Multiband { bit_depth: b, .. } => b,
|
|
}
|
|
}
|
|
|
|
/// The number of samples in each representation of a single color.
|
|
pub fn num_samples(&self) -> u16 {
|
|
match *self {
|
|
ColorType::Gray(_) => 1,
|
|
ColorType::RGB(_) => 3,
|
|
ColorType::Palette(_) => 1,
|
|
ColorType::GrayA(_) => 2,
|
|
ColorType::RGBA(_) => 4,
|
|
ColorType::CMYK(_) => 4,
|
|
ColorType::CMYKA(_) => 5,
|
|
ColorType::YCbCr(_) => 3,
|
|
ColorType::Lab(_) => 3,
|
|
ColorType::Multiband { num_samples, .. } => num_samples,
|
|
}
|
|
}
|
|
}
|