Canon c80 XF-AVC intra-frame files cause crash

OK, I filed it as bug #FB10671041, discussed it with Apple Pro Apps support, and emailed them the bug report. Below is the text of the bug. The attachments and other diagnostic data are on the below Dropbox link.

FCP Crash AppleAVCIntraCodec - Canon C80 All-Intra, All Resolutions and Frame Rates, Intel Only

Any version of the Canon EOS C80 All-Intra codec causes an immediate crash of Intel FCP 10.6.9 through 11.0.1.

The crash usually happens upon import, whether copy to library or leave files in place. MacOS versions

tested: Ventura 13.7.3, Sequoia 15.2, 15.3. It does not happen on Apple Silicon.

The main test machine was a 2019 i9 MacBook Pro 16, but it happens on other similar machines, including

a 2017 i7-8700K iMac 27 running Ventura 13.7.3.

The crashing thread is always four frames into AppleAVCIntraCodec, and several other threads are also

in that codec bundle, doing parallel processing of video data using Intel's Intel's SSE/AVX vector

instructions. This may imply a race condition when the crashing thread is managing the frame buffers

of the other threads during SIMD instructions. See attached crash files.

The fact it doesn't happen on Apple Silicon might be because the ARM NEON SIMD instructions may have

different memory alignment, buffer sizes or boundaries.

The EOS C80 is a new camera (release date November 2024), and it's currently not on the FCP support

list, but customers already have these and are encountering this problem.

See attached crash logs, sysdiagnose and MacOS System Report.

Machines tested:

2017 i7 iMac 27, 32GB, Ventura 13.7.3

2019 i9 MacBook Pro 16, 32GB, Sequoia 15.2, 15.3

2021 M1 Max MacBook Pro 16, 64GB, Sequoia 15.3

2022 M1 Ultra Mac Studio, 128GB, Sequoia 15.3

2024 M4 Pro Mac Mini 48GB, Sequoia 15.3

Replication Procedure:

- Use Finder to drag/drop the below MXF test clips to an event on an Intel Mac running FCP.

- It should crash immediately. It will often crash if importing a single file, and will crash

on any resolution, frame rate or bit rate of a C80 All-Intra file.

- However, the crash is more consistent if doing drag/drop import of all 13 files in the test group.

- The crash happens when either "copy to library" or "leave files in place" is selected, and using

the import dialog or Finder. However, most testing used "leave files in place” and drag/drop from Finder.

- Note the test clips are intentionally black.

- The resolution, frame rate and bit rate are part of the filenames.

- See attached MediaInfo metadata.

[Edited by Moderator]

I can reproduce the crash on a 2019 i9 MacBook Pro 16, but not on any Apple Silicon machine I've tested. There is apparently a bug in the AppleAVCIntraCodec "codec bundle" that manifests when handling the Canon C80 10-bit 4:2:2 All-Intra codec. It does not happen on all Intel machines and apparently never happens on Apple Silicon. It may have started with FCP 11.0 but I'll have to test older versions.

It happens on FCP 11.0 and 11.1 and also on MacOS 15.2 and 15.3. As previously mentioned, it doesn't require a complex procedure to reproduce. Often, just importing the clip via drag/drop from Finder will cause it, or just trying to skim the clip in the Event Browser.

My team shoots lots of Sony XAVC-I, which is a similar codec, and so far, we haven't seen this, but we mostly use Apple Silicon machines. I will test this further tomorrow.

There are multiple decoding threads executing code in AppleAVCIntraCodec, most of them doing SIMD (Single Instruction, Multiple Data) operations via Intel's SSE/AVX vector instructions. One thread may have been managing buffers for the other threads, and that one crashed. The crash sequence is the same each time.

There is probably a race condition or synchronization problem between the manager thread and all the other worker threads running vector instructions. That's why it crashes on some Intel machines but not others, or crashes with different frequency.

It might not crash on Apple Silicon because those use fundamentally different SIMD instructions. The memory alignment requirements and buffer sizes and boundaries might be different.

Here is a crash log from my 2019 Macbook:

Well it turns out I was wrong; it doesn't happen on Sony XAVC-I or XAVC-SI after all. I was confused because I had those plus the C80 All-Intra footage ingested to FCP, and when it crashes on the C80 footage, in some cases it will keep crashing when launching FCP. While playing a Sony XAVC-I clip in the timeline, with a C80 All-Intra clip in the Event Browser, if your skimmer just touches that clip, it can crash.

I tested several C-80 Long GOP clips and they were either OK or some only played sound (which is typical of new formats). But no Long GOP clip crashed FCP.

So currently it seems isolated to the Canon C80 All-Intra MXF clips.

@GC_film-images, the one clip I have from you is 3480 x 2160, 23.976 fps, 419 megabits/sec. Do any other frame rates or resolutions crash? If so, please upload me some samples of those.

Reason: Previously, some codec-related bug reports lacked coverage in the replication scenario. This resulted in a narrow fix, which required filing another bug with more details to achieve a broad fix. This extended the time needed to fix those related codec problems.

Crashes also in Mac mini 2018 Intel Sequoia 15.3. Just clicking the imported clip in the Browser repeatedly crashes FCP 11.0.1.

Send feedback to Apple:

Product Feedback - Apple

The Feedback Assistant page is pretty much a bit-bucket too, but not quite the direct-to-the-shredder type as the product feedback page.

https://feedbackassistant.apple.com

Or use Feedback Assistant app. It is a little hidden, but go to

/System/Library/Core Services/Applications (or use Spotlight to find it).

It also crashes on FCP 10.6.5 on a 2019 Mac Pro running Monterey 12.7.6. Note the C80 is not on the FCP-approved camera list, so it's not guaranteed to work, but it still should not crash: Cameras supported by Final Cut Pro - Apple Support

Is there a downloadable sample movie that triggers the issue?

It also happens on Sony XAVC-I, so it's not isolated to Canon C80 footage. That is a serious problem, so I'll be giving this priority today. I'll test all other similar codecs I have and verify it began with 11.0 and continues in 11.1. I'll try to verify it's isolated to Intel.

When complete I'll write up a formal bug report, file it using the MacOS Feedback Assistant app and call Apple to discuss.

@GC_film-images: Thanks so much for all the work! I downloaded the 13 new test files, and they all crash FCP 11.0 and 11.1 on Intel.

They also crash 10.8.1. Before this, I thought it was isolated to 11.0 and later. I'm now testing all my old versions of FCP. After I check the crash logs from that to ensure it's the same underlying problem, I'll go ahead and file a bug using the MacOS Feedback Assistant app, then call Apple to discuss.

Thank you Joema for all your work on this!