DFJPEGTurbo (Deprecated)
Objective-C libjpeg-turbo wrapper (JPEG image codec that uses SIMD instructions (MMX, SSE2, NEON) to accelerate baseline JPEG compression and decompression on x86, x86-64, and ARM systems). DFJPEGTurbo uses libjpeg-turbo version 1.4.1, which now includes arm64 support.
Requirements
- iOS 6.0
Examples
Decompressing JPEG
NSData *jpegData;
UIImage *image = [DFJPEGTurboImageDecoder imageWithData:data];Decompressing JPEG with one of the libjpeg-turbo scale factors
NSData *jpegData;
// Scale must be implemented by libjpeg-turbo which supports only several scaling factors (1/1, 1/2, 1/4 etc).
DFJPEGScale scale = DFJPEGScaleMake(1, 2); // 0.5 scale
UIImage *image = [DFJPEGTurboImageDecoder imageWithData:jpegData orientation:UIImageOrientationDown scale:scale];Benchmark (Baseline JPEG)
Benchmark on older ARM-based systems (iPhone 4S, iPhone 5C) shows that libjpeg-turbo provides a very noticable performance boost over native CGContextDrawImage. However, libjpeg-turbo underperforms on newer systems (iPhone 6). For benchmark implementation see Demo/DFJPEGTurboBenchmark in a project folder.
iPhone 6 (Apple A8)
| Input Image | CGContextDrawImage | libjpeg-turbo |
|---|---|---|
| 1024x768, 0.3 compression quality | 10.51 ms | 9.75 ms |
| 1024x768, 0.5 compression quality | 10.56 ms | 10.15 ms |
| 1024x768, 0.7 compression quality | 10.14 ms | 11.61 ms |
| 1024x768, 0.9 compression quality | 10.13 ms | 12.44 ms |
| 2048x1536, 0.3 compression quality | 41.60 ms | 36.98 ms |
| 2048x1536, 0.5 compression quality | 33.46 ms | 40.56 ms |
| 2048x1536, 0.7 compression quality | 33.85 ms | 45.53 ms |
| 2048x1536, 0.9 compression quality | 34.79 ms | 52.60 ms |
iPhone 5C (Apple A6)
| Input Image | CGContextDrawImage | DFJPEGTurbo |
|---|---|---|
| 1024x768, 0.3 compression quality | 42.47 ms | 22.26 ms |
| 1024x768, 0.5 compression quality | 40.75 ms | 23.28 ms |
| 1024x768, 0.7 compression quality | 40.51 ms | 26.11 ms |
| 1024x768, 0.9 compression quality | 39.82 ms | 29.77 ms |
| 2048x1536, 0.3 compression quality | 130.72 ms | 81.95 ms |
| 2048x1536, 0.5 compression quality | 129.83 ms | 86.50 ms |
| 2048x1536, 0.7 compression quality | 130.42 ms | 98.17 ms |
| 2048x1536, 0.9 compression quality | 130.03 ms | 106.18 ms |
Installation using CocoaPods
To install DFJPEGTurbo add a dependency in your Podfile.
pod 'DFJPEGTurbo'
Contacts
License
DFJPEGTurbo is available under the MIT license. See the LICENSE file for more info.