I have an application in which I have links for some videos and when requested by user I download the video files. The downloaded video files are listed in a UITableView. The app crashes occasionally with crash log similar to following.
Exception Type: EXC_BAD_ACCESS (SIGSEGV)
Exception Subtype: KERN_INVALID_ADDRESS at 0x6000000c
Triggered by Thread: 0
Thread 0 Crashed:
0 libobjc.A.dylib 0x3a03fb26 objc_msgSend + 6
1 MediaPlayer 0x30ba3ff0 -[MPAVController _setState:] + 288
2 MediaPlayer 0x30b97f1a -[MPAVController pauseWithFadeout:] + 198
3 MediaPlayer 0x30b9cd22 -[MPAVController _itemPlaybackDidEndNotification:] + 786
4 CoreFoundation 0x2f90011e __CFNOTIFICATIONCENTER_IS_CALLING_OUT_TO_AN_OBSERVER__ + 10
5 CoreFoundation 0x2f874312 _CFXNotificationPost + 1714
6 AVFoundation 0x2e780b6e __avplayeritem_fpItemNotificationCallback_block_invoke + 4094
7 libdispatch.dylib 0x3a527d78 _dispatch_call_block_and_release + 8
8 libdispatch.dylib 0x3a527d64 _dispatch_client_callout + 20
9 libdispatch.dylib 0x3a52e7bc _dispatch_main_queue_callback_4CF$VARIANT$mp + 264
10 CoreFoundation 0x2f90881c __CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE__ + 4
11 CoreFoundation 0x2f9070f0 __CFRunLoopRun + 1296
12 CoreFoundation 0x2f871ce2 CFRunLoopRunSpecific + 518
13 CoreFoundation 0x2f871ac6 CFRunLoopRunInMode + 102
14 GraphicsServices 0x3455f27e GSEventRunModal + 134
15 UIKit 0x32113a3c UIApplicationMain + 1132
16 MyApp 0x000e5884 main (main.m:30)
17 libdyld.dylib 0x3a54cab4 start + 0
The problem is that none of my own methods are shown to fail in the log. All calls seem to be library method calls. Also I wonder why _itemPlaybackDidEndNotification:
was called as I encountered this when I was not even playing a video.
Can someone help?
I found the issue in my case. I was using thumbnailImageAtTime:timeOption:
which seems to play/pause the video in the background(This is just my conjecture though) to get a thumbnail for it. That caused the itemPlaybackDidEndNotification
to fire despite me not playing any video explicitly and cause further issues.
There are now a couple of alternatives if someone else is using same method for getting thumbnails. The methods are mentioned here. thumbnailImageAtTime: now deprecated - What's the alternative?