Level 1

120 points

FCP 12.3: PNG in project causes export to fail on M4, works on M2

In an effort to track down more information for an open Apple Support ticket, maybe someone else has ran into this.

macOS 26.5.2 - freshly installed on an M4 Mac mini with 24GB RAM.
Final Cut Pro 12.3 - freshly installed on that M4 Mac

Existing projects that export fine on an M2 Mac fail on the M4 - no error, no pop up, it just starts, then a second or two later it fails.

I spent time with Support trying to figure out what was happening. There appears to be an issue with PNG and other files that affects the M4 but not the M2. Files that export fine on the M2 are not working on the M4.

I have four different PNGs I use, and they all fail.

I opened them up in preview, then exported a fresh PNG file. Same problem.
I converted them to HEIF, and tried them. Same failure. Again, works fine on the M2.
I converted them to TIFF, and tried them. Same failure.

But the more I check the more it looks like some kind of image handling issue with the M4 version of macOS.

M2 - just fine.

M4 - no export.

I have been focusing my testing on PNG files initially, and someone already pointed me to an older topic where someone had a very large PNG that would crash FCP. These are not very big. They are just logos (nadir logos for 360 video).

I can reproduce the failure -- but only on the M4 -- in both normal 1080 videos, and 360 videos now. Earlier today, they worked on normal videos on the M4, and now they do not. It is intermittent.

Has anyone had any issues with PNG files on an M4 Mac with the current macOS and FCP versions?

Mac mini (M4, 2024)

Posted on Jul 8, 2026 3:09 PM

Top-ranking reply

joema

Level 4

1,717 points

Posted on Jul 12, 2026 9:11 AM

It currently seems isolated to the M4, so other CPUs might not cause this. I can test on M2 Pro, M4 Pro, M1 Ultra and M1 Max (testing in progress right now), but I don't have an M5.

The simplest scenario is to resize a PNG image using Preview to 12001 x 12001 at 300 dpi. Procedure:

With image open in Preview, navigate to the top menu bar and select Tools > Adjust Size....
Set the Units: In the dialog box that appears, look at the dropdown menus immediately to the right of the Width and Height fields. Ensure they are set to pixels.
Adjust the Dimensions (X/Y):
Type 12001 value into the Width field.
Type 12001 value into the Height field.
Use 300 dpi (not sure this matters but it's what I used)

Then do this on an M4 running FCP 12.3:

Create a new library
Import the one 12001 x 12001 PNG file
Create a manual 1080p project (I used 23.98 fps but I don't think it matters)
Put only the PNG on timeline
Export this way: File > Share > Export File > Settings, Format: Computer, Video Codec: Single-Pass, Resolution: 1920 x 1080.

It fails 100% of the time with the FCP error "Share Failed." Examination of the macOS log via the terminal command "log show" indicates these errors:

(AppleProResHW) ERROR: AppleProResHW (0x67a7f6b8): 5547: processDecodeFrameDone(): HW error decStatus=2 status0=0x37046000 statusCode=55 status2=0x2 crccrd0d=0x66c2da58 crccrd1d=0xe57e399c

VTDecoderXPCService[53788]: (AppleProResHWDecoder) ERROR: AppleProResHW (0x67a7f6b8): 2151: <private>(): failed decoding proresStatus=2 HWErrorCode=0x37 convertedForEmit=0xffffcd91

VTDecoderXPCService[53788]: (AppleProResHWDecoder) AppleProResHW (0x67a7f6b8): <private>(): Emit to client status=0xffffcd91 for subFrameId=2

So it is failing to decode the input, not to encode the output.

I am examining the actual failure mode as part of gathering background info to support filing a high-quality bug report. I'll also conduct additional testing to determine boundary conditions, such as file type, timeline composition, etc.

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40 replies

Allen Huffman Author

Level 1

120 points

Jul 12, 2026 9:15 AM in response to Ian R. Brown

Ian R. Brown wrote:

...

How do you get Preview to create an image that size?

I downloaded a white square JPG from somewhere, and had no issue having Preview resize to different sizes. When it worked at 12000 and broke at 12100, I figured I'd found a range, and tested 120001.

And I can break it with 72dpi so I no longer thing 300 dps matters. I *think* the original issue was my graphics logo was probably based on a size (4" or whatever, since I use it for 3-D printing, laser engraving, etc.) and used 300 dpi. So a 4" logo at 72dpi is less pixels across than a 4" logo at 300dpi.

BenB

Level 6

13,996 points

Jul 9, 2026 10:42 AM in response to allenhuffman

Bug, report it to Apple via the FCP feedback page.

Feedback - Final Cut Pro - Apple

joema

Level 4

1,717 points

Jul 11, 2026 12:42 PM in response to Allen Huffman

My wife has an M4 Pro Mac Mini, so I will try this tomorrow morning. On my M1 Ultra Mac Studio, I cannot reproduce the exact problem, although at 24k horizontal pixels the image turns green. Using a 13k-pixel JPG on my M1 Ultra I don't see any problems with playback or export to H.264.

We will figure this out through testing, however you must keep in mind this is not image editing. Photoshop can edit very high-resolution images, but those are stills, and in Photoshop there is no expectation for video playback using those images.

In this case, you are putting these ultra-high-res images in a video timeline and expecting it to play normally at video speed. That means you are expecting the machine to decode and display without lag or halting, a 13k or 20k PNG image (or images) as if they were a video. If the FCP export was perfect but, when playing it in the timeline, it halted for 2 seconds each time it hit images like that, would that be OK? It is a still image, and FCP has no provision for stills proxies. Likewise, there is no hardware capability from Intel QuickSync, Nvidia NVDEC/NVENC, or Apple Silicon to do hardware-accelerated decoding of 13k-pixel stills.

The 12k x 12s PNG I created is 127 MB. That means a sequence of those at 24 fps would require 3 gigabytes per second decoding and I/O bandwidth for lag-free playback. This implies it will never be handled with video-like smoothness, even if there are just a few of them. But it seems that a single 13k-pixel image used as a background should be handled OK and should not cause an abort during FCP export.

You observe the exact same problem scenario works without the same issues on M2, but not M4. I also have an M2 Pro Mac Mini, and I will test it there for comparison with the M4.

IMO, if there is a limitation, it should not silently curtail the export. So even if there is a limitation, that seems wrong.

If there is a limitation in pixel size for stills, IMO that should be detected and flagged by the app, not cause a green frame or render exit. So even if it's not a good practice to put a 13k-pixel image on a video timeline, it should be handled gracefully.

To illustrate how a 13k-pixel PNG still is not that outlandish, the Blackmagic 12k cameras use a video frame size of 12,288 x 6480. So a single frame from those cameras encoded as a still is already over 12k. FCP currently does not yet natively support BRAW, but that is beside the point for this case.

Jul 11, 2026 4:48 PM in response to BenB

12,000 x 12,000 pixels? Why in the world would you use such a massive image? That about FOUR TIMES larger than a 4K video frame. And twice the size of an 8K frame.

Downsize the image to something sensible and I bet the problem goes away.

Allen Huffman Author

Level 1

120 points

Jul 12, 2026 11:48 AM in response to Old_Video_Guy

Old_Video_Guy wrote:

12,000 x 12,000 pixels? Why in the world would you use such a massive image? That about FOUR TIMES larger than a 4K video frame. And twice the size of an 8K frame.

Downsize the image to something sensible and I bet the problem goes away.

Agree.

When initially trying to figure out what was "wrong" with the logo files I have been using for years, I noticed they were all set to 300 dpi. Initially I thought that was the issue, but quickly disproved that. Then I thought 360 video projects were the issue. Then we recreated it with a basic 1080.

When I first went to try "other" images, I had a crash with a separate file that was 300dpi. However, this was actually a HUGE file -- the designer created it at some specific size -- 4" or whatever -- and 300dpi made it VERY large in resolution. THAT is how I found I could recreate this issue with 120001.

So far, I haven't found a workaround for using my normal and much smaller logo files. They just don't work on the M4, but I bet if I had one of the other programs folks have tested that work, I could re-export them as a workaround. I need to reach out to my designer who made the original logo files and see if she can send me some done with different programs.

Allen Huffman Author

Level 1

120 points

Jul 10, 2026 8:59 AM in response to Ian R. Brown

Ian R. Brown wrote:

It's such a unique problem that I doubt whether they will do anything especially as there are so many workarounds.

Well, the workaround for me is "don't edit on the M4". ;-)

I suspect it is some underlying issue with the Core Image routines that will get resolved since it likely impacts more than just FCP.

For my specific case, none of the built-in or free tools worked. But at least two pay-tools have been verified so far. I can resize mine since its just a logo and was never meant to be this large, but for those of us doing 8K-sized video editing, having larger images so you can zoom in and such is pretty common. It is just weird it breaks at 12000. I need to see if it is just the width or height that breaks. And maybe test 1-bit black and white versus 32-bit color to see if it has more to do with file size.

Allen Huffman Author

Level 1

120 points

Jul 11, 2026 8:37 PM in response to Old_Video_Guy

Old_Video_Guy wrote:

12,000 x 12,000 pixels? Why in the world would you use such a massive image? That about FOUR TIMES larger than a 4K video frame. And twice the size of an 8K frame.

Downsize the image to something sensible and I bet the problem goes away.

For you, and others not following, this image size is a way for other M4 users to see if they can replicate the bug. The actual image I was using was a nadir logo that goes at the bottom of a 360, but I quickly realized it was not that specific image, just images made that had some kind of issue on the M4 (whether it be PNG, HEIF, TIFF, etc.).

Also, even at this size, there is no problem to have go away on the M2. Images that have worked for years on the M2 version fail to export on the M4. 12001 just seems to be a breaking point that can trigger it, but I have small logo files that trigger it. Apple support didn’t want to do anything about it since they just said it was a bad image, so I showed them how they could recreate it using an image made by one of their own tools.

Jul 12, 2026 2:48 AM in response to Allen Huffman

I have done some quick tests . . . taken a 20 megapixel 4:3 from my Nikon and exported it as a JPEG from Photomator to 12,001 x 9,001 pixels, dropped it into a 1080p timeline and it exports normally.

I created another resized to 16,001 x 12,001 and that too exported.

Finally I made a PNG sized 16,001 x 12,001 and had no trouble exporting it.

So I can't replicate your problem.

This was the image I used though this one has been reduced to 1080 x 810.

Allen Huffman Author

Level 1

120 points

Jul 12, 2026 9:24 AM in response to Ian R. Brown

Also, here were some of the test files we sent to Apple:

https://www.dropbox.com/scl/fo/9rep68fofymidi58m4box/AGCB07hSwvquTXbyscXVDGw?rlkey=8ppw6ot5isogahkzkff58wtay&dl=0

As we find more programs that create images that M4 handles fine, I would like to add them to the folder. I started with a 1024x1024 white JPG, then just resized it in the various programs and exported it out. I have tested multiple image formats that all failed (PNG, TIFF, HEIF) so I just keep the PNGs there. It is clearly not limited to one specific image format.

Allen Huffman Author

Level 1

120 points

Jul 12, 2026 6:29 PM in response to joema

Rather various combinations of X/Y pixel dimensions fail, e.g,

11000 x 11008 works, but

11008 x 11000 fails

Great work! I wonder how small of an image we can get that causes it to fail? Now that I know 30,000 is not too big, and it can also fail smaller than my 12,000, I think if I could provide a "normal size" image that crashes the export folks may understand that this is not a "don't use big images" bug.

Jul 9, 2026 5:59 AM in response to Allen Huffman

UPDATE: My test program is now a basic 1080 export, nothing fancy, only containing a PNG. That is enough to make the M4 export fail.

Jul 12, 2026 2:56 AM in response to Ian R. Brown

I have noticed that FCP appears to resize the image.

When I select it in the Browser the Viewer shows it at 9% whereas in the Timeline it is 104%.

Jul 9, 2026 10:49 AM in response to BenB

BenB wrote:

Bug, report it to Apple via the FCP feedback page.

Feedback - Final Cut Pro - Apple

Yes. I have an existing case and today I was able to provide them enough details that they collected diagnostics and sample projects to forward to engineering. I wanted independent confirmation which I now have thanks to another M4 owner on FB retesting for me.

Jul 10, 2026 7:45 PM in response to terryb

terryb wrote:

@Allen Huffman, thank you for keeping us posted on the progress. We typically work with 4K material in HD projects and only ran into this issue with a png that was 3,256 × 37,546 pixels, which is well over 32,766 - the max size of a 16 bit integer. As I mentioned in other discussions, the M1 Ultra handled it fine but the M4 Pro MacMini would silently bail out on exports.

Yeah, a 16-bit limit would make sense. But 12001 seems ... almost like it was some intentional upper limit, which does not make sense.

Jul 10, 2026 10:15 PM in response to joema

I am baffled and curious.

Why would anyone need a 12,000 x 12,000 image? Those figures had not registered in my mind until now . . . I suppose I was thinking 1,200 x 1,200.

The highest resolution TVs commercially available (8K) are 7680 x 4320 and I don't know of anyone who has one.

Can cinema projectors resolve more and if so, is the human eye able to tell the difference under normal viewing conditions?

Or has the PNG to be so big because there is a need to zoom dramatically (like 10x) into it?

FCP 12.3: PNG in project causes export to fail on M4, works on M2