Ios CGImageDestinationFinalize时崩溃

我的应用程序允许用户使用照片框架编辑照片。我看到一些崩溃报告，看起来崩溃发生在生成输出图像时，但我不确定问题出在哪里。此崩溃发生在多个硬件设备和多个版本的iOS 9上，包括最新的9.1。我的应用程序最后一次调用是

cgmagedestinationfinalize

，以创建编辑的图像

NSData

。崩溃报告显示，在GLTextureManager中出现崩溃之前，调用在CoreImage空间中继续

这可能是内存不足的问题吗？你看到问题了吗？如何解决这个问题

来自

PhotoEditor.swift

的相关代码，内部函数

fullImageOutput

，从

editSingleAsset

调用，该函数在后台队列上运行，使用

QOS\u CLASS\u实用程序

：

let outputPhoto = //the generated CIImage that is the edited photo to be saved to disk
let dataRef = CFDataCreateMutable(nil, 0)

if let destination = CGImageDestinationCreateWithData(dataRef, "public.jpeg", 1, nil) {
    struct ContextStruct {
        static var ciContext: CIContext? = nil
    }
    if ContextStruct.ciContext == nil {
        let eaglContext = EAGLContext(API: .OpenGLES2)
        ContextStruct.ciContext = CIContext(EAGLContext: eaglContext)
    }
    let cgImage = ContextStruct.ciContext!.createCGImage(outputPhoto, fromRect: outputPhoto.extent)

    CGImageDestinationAddImage(destination, cgImage, nil)

    if CGImageDestinationFinalize(destination) { //FIXME: CRASH
       //write to disk from dataRef etc
    }

}

碰撞报告的可视化：

事故报告详情：

Exception Type:  EXC_BAD_ACCESS (SIGSEGV)
Exception Subtype: KERN_INVALID_ADDRESS at 0x0000000145201ac0
Triggered by Thread:  7

Thread 7 name:
Thread 7 Crashed:
0   libsystem_platform.dylib        0x0000000199e36220 _platform_memmove + 48 (memmove.s:220)
1   CoreImage                       0x0000000184e86e4c CI::GLTextureManager::texture_for_CGImage(CGImage*, CI::PixelFormat) + 372 (context-gles.cpp:910)
2   CoreImage                       0x0000000184e8a310 CI::GLContext::bind_textures(CI::SerialObjectPtrArray*, CI::Kernel*) + 240 (context-gles.cpp:3060)
3   CoreImage                       0x0000000184e899e0 CI::GLContext::render_apply_node(CI::Node const*, bool) + 160 (context-gles.cpp:2699)
4   CoreImage                       0x0000000184e897fc CI::GLContext::recursive_render(CI::Node*, bool) + 912 (context-gles.cpp:2379)
5   CoreImage                       0x0000000184e8a788 CI::GLContext::render(CI::Node*) + 180 (context-gles.cpp:2880)
6   CoreImage                       0x0000000184e9bfec CI::_get_bitmap(CI::Context*, CI::Image*, CGRect, CGColorSpace*, CI::Bitmap*) + 676 (render.cpp:2622)
7   CoreImage                       0x0000000184e9bc9c CI::image_get_bitmap(CI::Context*, CI::Image*, CGRect, CGColorSpace*, CI::Bitmap*, unsigned long) + 664 (render.cpp:2680)
8   CoreImage                       0x0000000184ea08e8 copyImageBlockSetOptsCallback(void*, CGImageProvider*, CGRect, CGSize, __CFDictionary const*) + 856 (imageProvider.h:143)
9   CoreGraphics                    0x0000000184af2198 CGImageProviderCopyImageBlockSet + 220 (CGImageProvider.c:500)
10  ImageIO                         0x0000000185baa41c GetBytesImageProvider + 484 (CGImagePixelDataProvider.c:382)
11  ImageIO                         0x0000000185c40440 _CGImagePluginWriteAppleJPEG + 2444 (imageAppleJPEG.c:2785)
12  ImageIO                         0x0000000185ba3020 CGImageDestinationFinalize + 724 (CGImageDestination.c:2119)
13  MyAppNameHere                   0x0000000100096468 _TFC11 MyAppNameHere 12PhotoEditor15fullImageOutputfS0_FT_GSqCSo22PHContentEditingOutput_ + 1272 (PhotoEditor.swift:71)
14  MyAppNameHere                   0x0000000100113310 _TFFFFFC11 MyAppNameHere 36PhotosPickerCollectionViewController16editSingleAssetFS0_FCSo7PHAssetT_U_FT_T_U0_FTGSqCSo21PHContentEditingInput_GVSs10DictionaryCSo8NSObjectPSs9AnyObject___T_U_FT_T_U_FT_T_ + 172 (PhotosPickerCollectionViewController.swift:851)
15  libdispatch.dylib               0x0000000199c296e8 _dispatch_call_block_and_release + 24 (init.c:761)
16  libdispatch.dylib               0x0000000199c296a8 _dispatch_client_callout + 16 (object.m:513)
17  libdispatch.dylib               0x0000000199c37b40 _dispatch_root_queue_drain + 2140 (inline_internal.h:1063)
18  libdispatch.dylib               0x0000000199c372dc _dispatch_worker_thread3 + 112 (queue.c:4250)
19  libsystem_pthread.dylib         0x0000000199e3d470 _pthread_wqthread + 1092 (pthread.c:1990)
20  libsystem_pthread.dylib         0x0000000199e3d020 start_wqthread + 4 (pthread_asm.s:191)

---

这是iOS 9中的一个已知问题，已在iOS 10中解决。源代码没有问题。

为什么我们应该期望CGImageDestinationFinalize是线程安全的？如果你到主线程去完成，崩溃会消失吗？@matt我自己还没能重现这次崩溃，但是，在主队列上完成不会导致新的崩溃，但会导致主线程在崩溃发生时被阻塞，从而防止用户取消正在进行的操作。@matt在Apple的SquareCam示例代码中，他们做了类似的操作，并在创建的串行队列上调用

CGImageDestinationFinalize