- Built-in Activity Indicator and Progress Indicator.
- iOS/tvOS/macOS cross-platform support.
#### Plugins
- All external image format coders are plugins. Supports WebP, HEIF, BPG, FLIF, SVG, PDF... Choose what you need in: [Coder Plugin List](https://github.com/SDWebImage/SDWebImage/wiki/Coder-Plugin-List)
- PhotoKit loader as a plugin: [SDWebImagePhotosPlugin](https://github.com/SDWebImage/SDWebImagePhotosPlugin)
- FLAnimatedImage integration as a plugin: [SDWebImageFLPlugin](https://github.com/SDWebImage/SDWebImageFLPlugin)
- YYImage/YYCache integration as a plugin: [SDWebImageYYPlugin](https://github.com/SDWebImage/SDWebImageYYPlugin)
### Improvements
#### Swift
- Better Swift support with some manual renaming APIs.
- Full nullability annotation.
- Using class property for shared instance.
- Using `NS_TYPED_ENUM` and `NS_STRING_ENUM` for better generated APIs.
#### API
- Using context option to control detail behavior for each image request beyond the limit of enums.
- Using prefetcher to manage token (list of URL requests) to avoid conflict.
- Use request modifier to modify constructed URLRequest.
## [5.0.0-beta4 - Customizable SDWebImage, on Jan 26th, 2019](https://github.com/rs/SDWebImage/releases/tag/5.0.0-beta4)
See [all tickets marked for the 5.0.0 release](https://github.com/rs/SDWebImage/milestone/15)
#### Features
- Expose the graphics helper method for coder plugin author and fix scale issue #2523
#### Performances
- Decrease animated decode times when cache enable #2468
- Remove kCGImageSourceShouldCache option when creating image source #2472
- Add autoreleasepool to release autorelease objects in advance when using GCD #2474
#### Fixes
- Add protect when custom animated image class image data is nil during progressive animation check #2466
- Fix background download #2500
#### Project
- Merged targets + MapKit dedicated target for Carthage installs #2476. Carthage user now does not enable MapKit support by default.
- Upgrade Xcode 10 + using xcconfig for project settings #2494
#### Notable Changes (from beta3)
Behavior:
- Move webp component (and libwebp dependency) to SDWebImage/SDWebImageWebPCoder #2469. Any user who use WebP in 5.0.0 should add [SDWebImageWebPCoder](https://github.com/SDWebImage/SDWebImageWebPCoder) to your Podfile or Cartfile instead.
- Refactory cache path about namespace && final cache directory #2535. Now the default disk cache path was moved to suitable path with the namespace.
- Use the memory bytes size, instead of pixel size to calculate the memory cost function #2568. Now the memory cost function use bytes size instead of pixels count.
Swift Only:
- Fix the accident changes of Swift API naming for `sd_imageDataAsFormat:`#2517
You can always check [5.0 migration guide](https://github.com/SDWebImage/SDWebImage/wiki/5.0-Migration-guide) for the latest information for these changes.
- Fix that WebP decoder in master branch, does not consider the global `shouldDecompressImages` config and always do pre-draw for static WebP images #2592
- Fix rare crash when NSMapTable empty keys #2556
- Retain operation when post download related notifications (Hopefully fix, but if you face crash, please open a issue) #2576
#### Performances
- Prioritize SDWebImageDownloaderHighPriority if operation already exists #2575
#### Project
- Let SD can be imported using static library by CocoaPods using `DEFINES_MODULE`#2549
- Fix the bug when `FLAnimatedImageView` firstly show one EXIF rotation JPEG `UIImage`, later animated GIF `FLAnimatedImage` will also be rotated #2406
- Replace `SDWebImageDownloaderOperation` with `NSOperation<SDWebImageDownloaderOperationInterface>` to make generic #2397
See the [5.0 Migration Guide](https://raw.githubusercontent.com/rs/SDWebImage/master/Docs/SDWebImage-5.0-Migration-guide.md) for a list of comprehensive changes and the way to update your code
- Moved `UIImage sd_imageLoopCount` and `UIImage isGIF` (and renamed to `sd_isAnimated`) to `UIImage+Metadata` category, removed the outdated methods #2152
- Move context and other type definitions to a separate header (`SDWebImageDefine`) to allow to be included without dependency #2188
- Pass `context` arg from the top level APIs to the bottom level APIs to allow specify logic in the future #2189 d6a3e2c c24c3d3
- Refactor the image indicator by creating `SDWebImageIndicator` and `SDWebImageProgressIndicator` protocols and two concrete classes that implement activity and progress indicators for both UIKit and AppKit #2185 46b62cf
- Refactor the implementation of `SDWebImagePrefetcher` so it behaves more like a "shared instance" object, similar to other platform classes. Each instance will manage its own list of urls. #2191 1efc247 92f3d2c bc164d6
- Use property instead of setters and getters to make the property available in Swift
- Use class property with the correct name instead of `+(instanceType)sharedInstance` in singleton to make it more easy to use in Swift. The generated interface should be simple `open class var shared { get }`
- Add all nullability annotation to avoid any `AnyObject!` implicitly unwrapped optionals (Except that `null_resettable`)
- Add all Core Foundation Ownership using `CF_RETURNS_RETAINED` for
Get Rule and `CF_RETURNS_NOT_RETAINED` for Create Rule to avoid any `Unmanaged` CF value
- Change all key for Dictionary with `NS_STRING_ENUM` to make it easy to use in Swift with dot syntax
- Change all global value type which represent enum with `NS_TYPED_ENUM` to make it easy to use in Swift with dot syntax
- Remove the extra calculation of image orientation for ImageIO coder & Fix macOS image orientation #2271
- Added `SDWebImageError` (defined as `NS_ERROR_ENUM`) to group all our errors together #2290
- Add the `SDWebImageContextStoreCacheType` context option to specify target cache type when the image is downloaded by manager and will store to cache #2360
- Feature watchOS `WKInterfaceImage` with `sd_setImageWithURL`#2331
- Add options to specify query cache sync/async behavior #2312
- Fixed issue #2001, add `sd_currentBackgroundImageURL` and `sd_backgroundImageURLForState:` for `UIButton`#2002
- Set `UIButton` placeholer-image even if the url is `nil`#2043 fixes #1721#1964 replaces #1790
- Use `CGImageSourceCreateIncremental` to perform progressive decoding instead of decode partial data each time from the beginning to improve performance and remove that gray background #2040 fixes #1899
- Fix *SDWebImage v4* can not import *libwebp* framework's header files #1983 fixes #1887
- Fix unreachable code build warning on `macOS`#1984
#### Improvements
- Performance enhancement related to single `WebP` and animated `WebP` decoding #1985 fixes #1999#1885
- add ability to change `NSURLSessionConfiguration` used by `SDWebImageDownloader`#1891 fixes #1870
- support animated GIF on `macOS`#1975
- cleanup the Swift interface by making unavailable all methods with missing params that have alternatives - see #1797 - this may cause require some changes in the Swift code
#### Fixes
- handle `NSURLErrorNetworkConnectionLost`#1767
- fixed `CFBundleVersion` and `CFBundleShortVersionString` not valid for all platforms #1784 + 23a8be8 fixes #1780
- fixed `UIActivityIndicator` not always initialized on main thread #1802 + a6af214 fixes #1801
-`SDImageCacheConfig` forward declaration changed to import #1805
- making image downloading cache policy more clearer #1737
- added `@autoreleasepool` to `SDImageCache.storeImage`#1849
- fixed 32bit machine `long long` type transfer to NSInteger may become negative #1879
- fixed crash on multiple concurrent downloads when accessing `self.URLOperations` dictionary #1911 fixes #1909#1950#1835#1838
- fixed crash due to incorrectly retained pointer to operation `self` which appears to create a dangled pointer #1940 fixes #1807#1858#1859#1821#1925#1883#1816#1716
- fixed Swift naming collision (due to the Obj-C interface that offers multiple variants of the same method but with mixed and missing params) #1797 fixes #1764
- coding style #1971
- fixed Umbrella header warning for the FLAnimatedImage (while using Carthage) d9f7cf4 (replaces #1781) fixes #1776
- fixed issue where animated image arrays could be populated out of order (order of download) #1452
- fixed animated WebP decoding issue, including canvas size, the support for dispose method and the duration per frame #1952 (replaces #1694) fixes #1951
## [4.0.0 beta 2 - New platforms (Mac OS X and watchOS) + refactoring, on Oct 6th, 2016](https://github.com/SDWebImage/SDWebImage/releases/tag/4.0.0-beta2)
- Add an option to scale down large images #787 00bf467 efad1e5 8d1a0ae. Fixed #538, #880 and #586. This one is a more robust solution than #884 or #894. Can be activated via `SDWebImageScaleDownLargeImages` or `SDWebImageDownloaderScaleDownLargeImages`
## [4.0.0 beta - New platforms (Mac OS X and watchOS) + refactoring, on Oct 5th, 2016](https://github.com/SDWebImage/SDWebImage/releases/tag/4.0.0-beta)
- removed all deprecated methods (that we carried around for backwards compatibility in previous versions) #774
- Renamed `SDWebImageManager``downloadImageWithURL:options:progress:completed:` to `loadImageWithURL:options:progress:completed:` as it makes more sense, since we check the cache first and download only if needed a32a177
-`SDWebImage `target that build as a static library (all subspecs included) -> `libSDWebImage.a`
-`SDWebImageiOS` and `SDWebImagetvOS` targets that build as dynamic frameworks
- Renamed the dynamic frameworks targets from `WebImage` to `SDWebImage`. Renamed the `WebImage.h` to `SDWebImage.h` to match the framework naming
- Renamed the schemes for consistency. Updated the Tests Podfile + project.
- For #883 Fix multiple requests for same image and then canceling one, several breaking changes were needed:
-`SDWebImageDownloader` method `- downloadImageWithURL:options:progress:completed:` now returns a `SDWebImageDownloadToken *` instead of `id <SDWebImageOperation>` (give the ability to cancel downloads using the returned token)
-`SDWebImageDownloaderOperation` initializer `- initWithRequest:options:progress:completed:cancelled` split into `- initWithRequest:options` and `addHandlersForProgress:completed:`. Note: there is no more cancel block
- Modern Objective-C syntax done in 64382b9 includes:
- initializers now return `instancetype` instead of `id`
- explicit designated initializers (i.e. for `SDImageCache`)
- For #1575 GIF support using FLAnimatedImage, several changes were needed:
- replaced type `SDWebImageQueryCompletedBlock` with `SDCacheQueryCompletedBlock` and added an `NSData *` param
- because of the change above, the `done` param of `SDImageCache``queryDiskCacheForKey:done:` is now a `SDCacheQueryCompletedBlock` and those blocks must now include an `NSData *` param
- replaced type `SDWebImageCompletionWithFinishedBlock` with `SDInternalCompletionBlock` and added an `NSData *` param
- because of the change above, the `completed` param of `SDWebImageManager``loadImageWithURL:options:progress:completed:` is now `SDInternalCompletionBlock` and those blocks must now include an `NSData *` param
- for consistency with the previous change, also renamed `SDWebImageCompletionBlock` to `SDExternalCompletionBlock`
-`UIImage` will no longer respond to `sd_animatedGIFNamed:` or `sd_animatedImageByScalingAndCroppingToSize:`
- Xcode 7 Objective-C updates (Lightweight Generics and Nullability) #1581
- breaks compatibility at least for Swift users of the framework
- **watchOS** and **OS X** support #1595 required
- renamed `SDWebImage` iOS static lib target to `SDWebImage iOS static` for clarity
- improving the unit tests code coverage #1681 required
- Refactored `NSData``ImageContentType` category, instead of returning the contentType as a string, the new added method `sd_imageFormatForImageData` will return a `SDImageFormat` enum value
- The `storeImage:` methods from `SDImageCache` were async already, but declared as sync. Properly marked them as async + added completion. Got rid of the recalculate param. If the `NSData` is provided, use it. Otherwise, recalculate from the `UIImage`
- Removed the synchronous methods `diskImageExistsForURL:` and `cachedImageExistsForURL:` from `SDWebImageManager`
- Removed the synchronous method `diskImageExistsWithKey:` from `SDImageCache`
- Get rid of the confusion caused by `cleanDisk` and `clearDisk` on `SDImageCache`. Renamed `cleanDisk` to `deleteOldFiles`. No longer expose the sync `clearDisk` and `deleteOldFiles`, just the async ones.
- Renamed `SDImageCache``queryDiskCacheForKey:done:` to `queryCacheOperationForKey:done:`
- Another `SDImageCache` clarification: `imageFromDiskCacheForKey:` used to also check the memory cache which I think is misleading. Now `imageFromDiskCacheForKey` only checks the disk cache and the new method `imageFromCacheForKey` checks both caches
- Got rid of `removeImageForKey:` and `removeImageForKey:fromDisk:` from `SDImageCache` that looked sync but were async. Left only the 2 async ones
- Switched our GIF support to a better implementation: [FLAnimatedImage by Flipboard](https://github.com/Flipboard/FLAnimatedImage) #1575
- requires iOS 8+ (it's the only way due to FLAnimatedImage requirements)
- the implementation relies on a `WebCache` category on top of `FLAnimatedImageView`
- details in the [README](README.md#animated-images-gif-support)
- Converted any remaining code to Modern Objective-C syntax - 64382b9
- Xcode 7 Objective-C updates (Lightweight Generics and Nullability) #1581
- via #1595 Clarified and simplified the usage of `TARGET_OS_*` macros. Added `SD_MAC`, `SD_UIKIT`, `SD_IOS`, `SD_TV`, `SD_WATCH`. The biggest issue here was `TARGET_OS_MAC` was 1 for all platforms and we couldn't rely on it.
- Replaces #1398 Allow to customise cache and image downloader instances used with `SDWebImageManager` - added a new initializer (`initWithCache:downloader:`) 9112170
-`UIImage` responds to `sd_imageData` and `sd_imageDataAsFormat:` via the `MultiFormat` category. Those methods transform a `UIImage` to the `NSData` representation 82d1f2e
- Created `SDWebImageDownloaderOperationInterface` to describe the behavior of a downloader operation. Any custom operation must conform to this protocol df3b6a5
- Refactored all the duplicate code from our `WebCache` categories into a `UIView``WebCache` category. All the other categories will make calls to this one. Customization of setting the image is done via the `setImageBlock` and the `operationKey` e1840c3
- Due to the change above, the activity indicator can now be added to `UIButton`, `MKAnnotationView`, `UIImageView`
- The shared objects (not really singletons) should allow subclassing, therefore the return type of the shared resource method should be `instancetype` and not a fixed type - c57cf7e
- Allow to specify `NSURLSessionConfiguration` for `SDWebImageDownloader`#1654
- Add `url` as param to progress block `SDWebImageDownloaderProgressBlock` - #984
- Fixed an issue with the `SDWebImageDownloaderOperation` : `cancelInternal` was not called because of the old mechanism rellying on the `thread` property - probably because that thread did not have a runloop. Removed that and now cancelInternal is called as expected f4bdae6
- Replaced #781 on replacing dispatch_sync with dispatch_async for the main queue 062e50a f7e8246 c77adf4 fdb8b2c 265ace4 0c47bc3. Check for main queue instead of main thread.
- Fixed #1608#1623#1644 Crash in `[NSURLCache cachedResponseForRequest:]` - the fix is actually avoiding to access `NSURLCache` which appears to generate a race condition. We only call it if necesarry (`SDWebImageRefreshCached` is used and the image cannot be cached by the system when it's too big or behind authentication)
- SDWebImage 3.8.0 get wrong image #1589 - the issue was caused by the changes in 3.8.0 (Removed the URL query params from the filename (key) fb0cdb6d 1bf62d4 #1584 - fixes #1433#1553#1583#1585) - Reverted.
- Note: The solution for those issues (i.e. #1433#1553) is to set the `SDWebImageManager``cacheKeyFilter` block and do their own calculations there.
## [3.8.0 Minor release - Replaces NSURLConnection (deprecated) with NSURLSession - on Jun 6th, 2016](https://github.com/SDWebImage/SDWebImage/releases/tag/3.8.0)
- Changed the **libwebp git url** so that people from China can access it - #1390 (from `https://chromium.googlesource.com/webm/libwebp` to `https://github.com/webmproject/libwebp`)
#### Features:
- Added `cancelAllDownloads` method to `SDWebImageDownloader`#1504
- Added API to save image `NSData` to disk cache: `[SDImageCache storeImageDataToDisk:forKey:]`#1453
#### Fixes:
- Fix #1449: Version 3.7.5 breaks semantic versioning (removes public API). Re-added `sd_setImageWithPreviousCachedImageWithURL:andPlaceholderImage:options:progress:completed:` and deprecated it. Will remove it in 4.0.0 b40124c
- fixed #1425 and #1426 - Continuation of Fix #1366, addresses #1350 and reverts a part of #1221 - from commit 6406d8e, the wrong usage of `dispatch_apply`
- fixed #1422 - Added a fallback for #976 so that if there are images saved with the old format (no extension), they can still be loaded
-#1348 Create a strong ref of weakOperation in the entry of The image download subOperation, use the strong ref instead weakOperation. At the same time, repair some logic of the 'If cancelled'
- dcb7985 replaces #1345 - Load local credential file
-#1323 don't to perform download if url is "" but not nil
-#1310 Added support for SDWebImageAvoidAutoSetImage option to UIButton and highlighted UIImageView categories
-#1308 Added Swift installation tips
- 32923fa Xcode 7.1 updates
-#1297 cleaner implementation of failedUrl error handling - fixes #1275
## [3.7.3 Patch release for 3.7.0 with iOS8+ framework and Carthage on Jun 13th, 2015](https://github.com/SDWebImage/SDWebImage/releases/tag/3.7.3)
- Adds support for **iOS 8+ Framework and Carthage** [#1071](https://github.com/SDWebImage/SDWebImage/pull/1071) [#1081](https://github.com/SDWebImage/SDWebImage/pull/1081) [#1101](https://github.com/SDWebImage/SDWebImage/pull/1101)
- [Refactor] Use `NSMutableSet` for failed URLs' storage instead of array [#1076](https://github.com/SDWebImage/SDWebImage/pull/1076)
- Make a constant for the error domain [#1011](https://github.com/SDWebImage/SDWebImage/pull/1011)
- Bug fix: `Collection <__NSArrayM: > was mutated while being enumerated` [#985](https://github.com/SDWebImage/SDWebImage/pull/985)
- added `SDWebImageAvoidAutoSetImage` option to avoid automatic image addition in `UIImageView` and let developer to do it himself [#1188](https://github.com/SDWebImage/SDWebImage/pull/1188)
- Added support for custom disk cache folder with fall back for caches directory [#1153](https://github.com/SDWebImage/SDWebImage/pull/1153)
- Added some files to the workspace so they are easier to edit [8431481](https://github.com/SDWebImage/SDWebImage/commit/8431481)
- [Memory Issue] Clear `SDWebImagePrefetcher``progressBlock` when it has completed [#1017](https://github.com/SDWebImage/SDWebImage/pull/1017)
- avoid warning `<Error>: ImageIO: CGImageSourceCreateWithData data parameter is nil` if `imageData` is nil [88ee3c6](https://github.com/SDWebImage/SDWebImage/commit/88ee3c6) [#1018](https://github.com/SDWebImage/SDWebImage/pull/1018)
-`failedURLs` can be removed at the appropriate time [#1111](https://github.com/SDWebImage/SDWebImage/pull/1111)
- Purge `NSCache` on system memory notifications [#1143](https://github.com/SDWebImage/SDWebImage/pull/1143)
- Determines at runtime is `UIApplication` is available as per [#1082](https://github.com/SDWebImage/SDWebImage/issues/1082) [#1085](https://github.com/SDWebImage/SDWebImage/pull/1085)
- 404 image url was causing the test to fail [0e761f4](https://github.com/SDWebImage/SDWebImage/commit/0e761f4)
- Fix for transparency being lost in transformed images. [#1121](https://github.com/SDWebImage/SDWebImage/pull/1121)
- Add handling for additional error codes that shouldn't be considered a permanent failure [#1159](https://github.com/SDWebImage/SDWebImage/pull/1159)
- add webp accepted content type only if `WebP` enabled [#1178](https://github.com/SDWebImage/SDWebImage/pull/1178)
- fix `ImageIO: CGImageSourceCreateWithData` data parameter is nil [#1167](https://github.com/SDWebImage/SDWebImage/pull/1167)
- Applied patch for issue [#1074](https://github.com/SDWebImage/SDWebImage/issues/1074) SDWebImage residing in swift module breaks the debugger [#1138](https://github.com/SDWebImage/SDWebImage/pull/1138)
- Fixed URLs with trailing parameters get assigned an incorrect image scale value [#1157](https://github.com/SDWebImage/SDWebImage/issues/1157) [#1158](https://github.com/SDWebImage/SDWebImage/pull/1158)
- Add newline to avoid compiler warning in `WebImage.h` [#1199](https://github.com/SDWebImage/SDWebImage/pull/1199)
## [3.7.2 Updated patch release for 3.7.0 on Mar 17th, 2015](https://github.com/SDWebImage/SDWebImage/releases/tag/3.7.2)
- fixed [#900](https://github.com/SDWebImage/SDWebImage/issues/900) by adding a new flag `SD_LOG_NONE` that allows silencing the SD logs from the Prefetcher
- fixed [#895](https://github.com/SDWebImage/SDWebImage/issues/895) unsafe setImage in `setImageWithURL:` - [#896](https://github.com/SDWebImage/SDWebImage/pull/896)
- fix `NSNotificationCenter` dispatch on subthreads - [#987](https://github.com/SDWebImage/SDWebImage/pull/987)
- the code from `SDWebImageDownloaderOperation connection:didFailWithError:` should match the code from `connectionDidFinishLoading:`. This fixes [#872](https://github.com/SDWebImage/SDWebImage/issues/872) - [7f39e5e](https://github.com/SDWebImage/SDWebImage/commit/7f39e5e)
-`304 - Not Modified` HTTP status code handling - [#942](https://github.com/SDWebImage/SDWebImage/pull/942)
- Exposing `SDWebImageManager` instance from the `SDWebImagePrefetcher` class - [6c409cd](https://github.com/SDWebImage/SDWebImage/commit/6c409cd)
-`SDWebImageManager` uses the shared instance of `SDWebImageDownloader` - [0772019](https://github.com/SDWebImage/SDWebImage/commit/0772019)
- Refactor the cancel logic - [#771](https://github.com/SDWebImage/SDWebImage/pull/771) [6d01e80](https://github.com/SDWebImage/SDWebImage/commit/6d01e80) [23874cd](https://github.com/SDWebImage/SDWebImage/commit/23874cd) [a6f11b3](https://github.com/SDWebImage/SDWebImage/commit/a6f11b3)
- Added method `SDWebImageManager cachedImageExistsForURL:` to check if an image exists in either the disk OR the memory cache - [#644](https://github.com/SDWebImage/SDWebImage/pull/644)
- Added option to use the cached image instead of the placeholder for `UIImageView`. Replaces [#541](https://github.com/SDWebImage/SDWebImage/pull/541) - [#599](https://github.com/SDWebImage/SDWebImage/issues/599) [30f6726](https://github.com/SDWebImage/SDWebImage/commit/30f6726)
- Fixed race condition that causes cancellation of one download operation to stop a run loop that is now used for another download operation. Race is introduced through `performSelector:onThread:withObject:waitUntilDone:` - [#698](https://github.com/SDWebImage/SDWebImage/pull/698)
- Fixed race condition between operation cancelation and loading finish - [39db378](https://github.com/SDWebImage/SDWebImage/commit/39db378) [#621](https://github.com/SDWebImage/SDWebImage/pull/621) [#783](https://github.com/SDWebImage/SDWebImage/pull/783)
- Fixed race condition in SDWebImageManager if one operation is cancelled - [f080e38](https://github.com/SDWebImage/SDWebImage/commit/f080e38) [#699](https://github.com/SDWebImage/SDWebImage/pull/699)
- Fixed issue where cancelled operations aren't removed from `runningOperations` - [#68](https://github.com/SDWebImage/SDWebImage/issues/68)
- Should not add url to failedURLs when timeout, cancel and so on - [#766](https://github.com/SDWebImage/SDWebImage/pull/766) [#707](https://github.com/SDWebImage/SDWebImage/issues/707)
- Fixed potential *object mutated while being enumerated* crash - [#727](https://github.com/SDWebImage/SDWebImage/pull/727) [#728](https://github.com/SDWebImage/SDWebImage/pull/728) (revert a threading fix from [#727](https://github.com/SDWebImage/SDWebImage/pull/727))
- Fixed `NSURLConnection` response statusCode not valid (e.g. 404), downloader never stops its runloop and hangs the operation queue - [#735](https://github.com/SDWebImage/SDWebImage/pull/735)
- Fixed `SDWebImageRefreshCached` bug for large images - [#744](https://github.com/SDWebImage/SDWebImage/pull/744)
- Added proper handling for `SDWebImageDownloaderLowPriority` - [#713](https://github.com/SDWebImage/SDWebImage/issues/713) [#745](https://github.com/SDWebImage/SDWebImage/issues/745)
- Fixed fixing potential bug when sending a nil url for UIButton+WebCache - [#761](https://github.com/SDWebImage/SDWebImage/issues/761) [#763](https://github.com/SDWebImage/SDWebImage/pull/763)
- Fixed issue [#529](https://github.com/SDWebImage/SDWebImage/pull/529) - if the `cacheKeyFilter` was set, this was ignored when computing the `scaledImageForKey`. For most of the developers that did not set `cacheKeyFilter`, the code will work exactly the same - [eb91fdd](https://github.com/SDWebImage/SDWebImage/commit/eb91fdd)
- Returning error in setImage completedBlock if the url was nil. Added `dispatch_main_async_safe` macro - [#505](https://github.com/SDWebImage/SDWebImage/issues/505) [af3e4f8](https://github.com/SDWebImage/SDWebImage/commit/af3e4f8)
- Avoid premature completion of prefetcher if request fails - [#751](https://github.com/SDWebImage/SDWebImage/pull/751)
- Return nil from `SDScaledImageForKey` if the input image is nil - [#365](https://github.com/SDWebImage/SDWebImage/issues/365) [#750](https://github.com/SDWebImage/SDWebImage/pull/750)
- Do not load placeholder image if `SDWebImageDelayPlaceholder` option specified - [#780](https://github.com/SDWebImage/SDWebImage/pull/780)
- Make sure we call the `startPrefetchingAtIndex:` method from main queue - [#694](https://github.com/SDWebImage/SDWebImage/pull/694)
- Save image in cache before calling completion block - [#700](https://github.com/SDWebImage/SDWebImage/pull/700)
