https://github.com/tayloraswift/swift-jpeg
decode, inspect, edit, and encode jpeg images in pure swift
https://github.com/tayloraswift/swift-jpeg
codec jpeg multimedia-codecs pure-swift swift
Last synced: 7 months ago
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decode, inspect, edit, and encode jpeg images in pure swift
- Host: GitHub
- URL: https://github.com/tayloraswift/swift-jpeg
- Owner: tayloraswift
- License: apache-2.0
- Created: 2017-11-06T07:38:33.000Z (almost 8 years ago)
- Default Branch: master
- Last Pushed: 2024-11-21T16:02:46.000Z (11 months ago)
- Last Synced: 2024-11-29T21:28:32.805Z (11 months ago)
- Topics: codec, jpeg, multimedia-codecs, pure-swift, swift
- Language: Swift
- Homepage: https://swiftinit.org/docs/swift-jpeg/jpeg
- Size: 61.6 MB
- Stars: 150
- Watchers: 8
- Forks: 18
- Open Issues: 6
-
Metadata Files:
- Readme: README.md
- Funding: .github/FUNDING.yml
- License: LICENSE
Awesome Lists containing this project
README
***`jpeg`***
[](https://github.com/tayloraswift/swift-jpeg/actions/workflows/Tests.yml)
[](https://github.com/tayloraswift/swift-jpeg/actions/workflows/Documentation.yml)
Swift *JPEG* is a cross-platform pure Swift framework for decoding, inspecting, editing, and encoding JPEG images. The core framework has no external dependencies, including *Foundation*, and should compile and provide consistent behavior on *all* Swift platforms. The framework supports additional features, such as file system support, on Linux and MacOS.
Swift *JPEG* is available under the [Apache 2.0 License](LICENSE). The [example programs](Snippets/) are public domain and can be adapted freely.
[documentation](https://swiftinit.org/docs/swift-jpeg/jpeg) ·
[license](LICENSE)
## Requirements
The swift-jpeg library requires Swift 5.10 or later.
| Platform | Status |
| -------- | ------ |
| 🐧 Linux | [](https://github.com/tayloraswift/swift-jpeg/actions/workflows/Tests.yml) |
| 🍏 Darwin | [](https://github.com/tayloraswift/swift-jpeg/actions/workflows/Tests.yml) |
| 🍏 Darwin (iOS) | [](https://github.com/tayloraswift/swift-jpeg/actions/workflows/iOS.yml) |
| 🍏 Darwin (tvOS) | [](https://github.com/tayloraswift/swift-jpeg/actions/workflows/tvOS.yml) |
| 🍏 Darwin (visionOS) | [](https://github.com/tayloraswift/swift-jpeg/actions/workflows/visionOS.yml) |
| 🍏 Darwin (watchOS) | [](https://github.com/tayloraswift/swift-jpeg/actions/workflows/watchOS.yml) |
[Check deployment minimums](https://swiftinit.org/docs/swift-jpeg#ss:platform-requirements)
## [tutorials and example programs](examples/)
* [basic decoding](examples#basic-decoding)
* [basic encoding](examples#basic-encoding)
* [advanced decoding](examples#advanced-decoding)
* [advanced encoding](examples#advanced-encoding)
* [using in-memory images](examples#using-in-memory-images)
* [online decoding](examples#online-decoding)
* [requantizing images](examples#requantizing-images)
* [lossless rotations](examples#lossless-rotations)
* [custom color formats](examples#custom-color-formats)
## [api reference](https://swiftinit.org/docs/swift-jpeg/jpeg/)
* [`JPEG.JPEG`](https://swiftinit.org/docs/swift-jpeg/jpeg/jpeg)
* [`JPEG.General`](https://swiftinit.org/docs/swift-jpeg/jpeg/general)
* [`JPEG.System`](https://swiftinit.org/docs/swift-jpeg/jpegsystem/system)
## getting started
To Swift *JPEG* in a project, add this descriptor to the `dependencies` list in your `Package.swift`:
```swift
.package(url: "https://github.com/tayloraswift/swift-jpeg", from: "2.0.0")
```
## basic usage
Decode an image:
```swift
import JPEG
func decode(jpeg path:String) throws
{
guard let image:JPEG.Data.Rectangular = try .decompress(path: path)
else
{
// failed to access file from file system
}
let rgb:[JPEG.RGB] = image.unpack(as: JPEG.RGB.self),
size:(x:Int, y:Int) = image.size
// ...
}
```
Encode an image:
```swift
import JPEG
func encode(jpeg path:String, size:(x:Int, y:Int), pixels:[JPEG.RGB],
compression:Double) // 0.0 = highest quality
throws
{
let layout:JPEG.Layout = .init(
format: .ycc8,
process: .baseline,
components:
[
1: (factor: (2, 2), qi: 0), // Y
2: (factor: (1, 1), qi: 1), // Cb
3: (factor: (1, 1), qi: 1), // Cr
],
scans:
[
.sequential((1, \.0, \.0), (2, \.1, \.1), (3, \.1, \.1)),
])
let jfif:JPEG.JFIF = .init(version: .v1_2, density: (72, 72, .inches))
let image:JPEG.Data.Rectangular =
.pack(size: size, layout: layout, metadata: [.jfif(jfif)], pixels: rgb)
try image.compress(path: path, quanta:
[
0: JPEG.CompressionLevel.luminance( compression).quanta,
1: JPEG.CompressionLevel.chrominance(compression).quanta
])
}
```