The application crashes when playing AV1 videos

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Steps to reproduce

1.Play an AV1-encoded 1080P video using an iOS application.

Expected behaviour

The video plays normally until the end.

Actual behaviour

The application crashes during video playback.

Logs

{"app_name":"Nextcloud","timestamp":"2026-01-04 22:33:01.00 +0800","app_version":"7.2.2","slice_uuid":"***","adam_id":"***","build_version":"4","bundleID":"it.twsweb.Nextcloud","platform":2,"share_with_app_devs":0,"is_first_party":0,"bug_type":"309","os_version":"iPhone OS 26.2 (23C55)","roots_installed":0,"incident_id":"***","name":"Nextcloud"}
{
  "uptime" : 150000,
  "procRole" : "Foreground",
  "version" : 2,
  "userID" : ***,
  "deployVersion" : 210,
  "modelCode" : "iPhone17,1",
  "coalitionID" : 1151,
  "osVersion" : {
    "isEmbedded" : true,
    "train" : "iPhone OS 26.2",
    "releaseType" : "User",
    "build" : "23C55"
  },
  "captureTime" : "2026-01-04 22:33:00.4152 +0800",
  "codeSigningMonitor" : 2,
  "incident" : "***",
  "pid" : 20615,
  "translated" : false,
  "cpuType" : "ARM-64",
  "procLaunch" : "2026-01-04 22:32:10.7391 +0800",
  "procStartAbsTime" : ***,
  "procExitAbsTime" : ***,
  "procName" : "Nextcloud",
  "procPath" : "\/private\/var\/containers\/Bundle\/Application\/***\/Nextcloud.app\/Nextcloud",
  "bundleInfo" : {"CFBundleShortVersionString":"7.2.2","CFBundleVersion":"4","CFBundleIdentifier":"it.twsweb.Nextcloud","DTAppStoreToolsBuild":"17B101"},
  "storeInfo" : {"itemID":"***","storeCohortMetadata":"***","distributorID":"com.apple.AppStore","deviceIdentifierForVendor":"***","softwareVersionExternalIdentifier":"***","applicationVariant":"1:iPhone17,1:18","thirdParty":true},
  "parentProc" : "launchd",
  "parentPid" : 1,
  "coalitionName" : "it.twsweb.Nextcloud",
  "crashReporterKey" : "***",
  "appleIntelligenceStatus" : {"state":"unavailable","reasons":["countryLocationIneligible","selectedSiriLanguageIneligibleInfo(und)","selectedSiriLanguageIneligible","regionIneligible"]},
  "bootProgressRegister" : "0x2080000c",
  "wasUnlockedSinceBoot" : 1,
  "isLocked" : 0,
  "codeSigningID" : "it.twsweb.Nextcloud",
  "codeSigningTeamID" : "***",
  "codeSigningFlags" : 570450689,
  "codeSigningValidationCategory" : 4,
  "codeSigningTrustLevel" : 5,
  "codeSigningAuxiliaryInfo" : 0,
  "instructionByteStream" : {"beforePC":"***","atPC":"***"},
  "bootSessionUUID" : "***",
  "basebandVersion" : "2.20.04",
  "vmRegionInfo" : "***",
  "exception" : {"codes":"0x0000000000000001, 0x000000013c3fffff","rawCodes":[1,5305794559],"type":"EXC_BAD_ACCESS","signal":"SIGSEGV","subtype":"KERN_INVALID_ADDRESS at 0x000000013c3fffff"},
  "termination" : {"flags":0,"code":11,"namespace":"SIGNAL","indicator":"Segmentation fault: 11","byProc":"exc handler","byPid":20615},
  "vmregioninfo" : "***",
  "faultingThread" : 16,
  "threads" : [...],
  "usedImages" : [...],
  "sharedCache" : {
  "base" : 6592937984,
  "size" : 5133762560,
  "uuid" : "***"
},
  "vmSummary" : "ReadOnly portion of Libraries: Total=1.6G resident=0K(0%) swapped_out_or_unallocated=1.6G(100%)\nWritable regions: Total=301.1M written=817K(0%) resident=817K(0%) swapped_out=0K(0%) unallocated=300.3M(100%)\n\n                                VIRTUAL   REGION \nREGION TYPE                        SIZE    COUNT (non-coalesced) \n===========                     =======  ======= \nActivity Tracing                   256K        1 \nAttributeGraph Data               1024K        1 \nAudio                               64K        1 \nCG raster data                    16.6M      142 \nCoreAnimation                     5536K      171 \nFoundation                          16K        1 \nKernel Alloc Once                   32K        1 \nMALLOC                           262.8M       58 \nMALLOC guard page                 3664K        4 \nMach message                        16K        1 \nSQLite page cache                  512K        4 \nSTACK GUARD                        400K       25 \nStack                             20.2M       26 \nVM_ALLOCATE                       1120K       26 \n__AUTH                            6829K      627 \n__AUTH_CONST                      92.7M     1002 \n__CTF                               824        1 \n__DATA                            52.5M      953 \n__DATA_CONST                      31.9M     1007 \n__DATA_DIRTY                      8377K      881 \n__FONT_DATA                        2352        1 \n__GLSLBUILTINS                    1903K        1 \n__INFO_FILTER                         8        1 \n__LINKEDIT                       216.7M        6 \n__OBJC_RO                         84.3M        1 \n__OBJC_RW                         3177K        1 \n__TEXT                             1.4G     1028 \n__TEXT (graphics)                 28.7M        1 \n__TPRO_CONST                       128K        2 \nmapped file                      423.5M       42 \nmapped file (graphics)             480K        1 \npage table in kernel               817K        1 \nshared memory                       80K        4 \n===========                     =======  ======= \nTOTAL                              2.6G     6023 \n",
  "legacyInfo" : {
  "threadTriggered" : {
    "name" : "dav1d-worker"
  }
},
  "logWritingSignature" : "***",
  "bug_type" : "309",
  "roots_installed" : 0,
  "trmStatus" : 1,
  "trialInfo" : {
  "rollouts" : [
    {
      "rolloutId" : "639124e81d92412bfb4880b3",
      "factorPackIds" : [

      ],
      "deploymentId" : 240000012
    },
    {
      "rolloutId" : "6434420a89ec2e0a7a38bf5a",
      "factorPackIds" : [

      ],
      "deploymentId" : 240000011
    }
  ],
  "experiments" : [

  ]
}
}

Reasoning or why should it be changed/implemented?

I hope to be able to play av1 encoded videos normally.

Environment data

iOS version: iPhone OS 26.2 (23C55)

Nextcloud iOS app version: 7.2.2

Server operating system: debian bookworm

Web server: Apache, nginx

Database: PostgreSQL 17.7

PHP version: 8.4.16

Nextcloud version: Nextcloud Hub 10 (31.0.12)

Start by reproducing AV1-encoded 1080p playback in the iOS application and inspect the crash log, especially the dav1d-worker thread and EXC_BAD_ACCESS details. Trace the playback path involved in that crash; done means the video plays through to the end without the application crashing.