Aegisub not work with 4K video?

[Vinnems]

Does Aegisub not work with 4K video? Have a few 4K movies in MPEG-H/HEVC/H.265 (according to MKVToolNix) ripped from 4K BDs that I'm trying to add subtitles to. The error I get is:

An unexpected error has occurred. Please save your work and restart Aegisub.
Error Message: One or more characters could not be converted to the selected target encoding and the version of iconv Aegisub was built with does not have useful fallbacks. For best results, please build Aegisub using a recent version of GNI iconv.

If not, would I be able to create a temporary 1080 version of the video and edit/position subtitles, and then have it scale properly to the 4K video version?

[sneaker]

I don't see why not. Try latest 64 bit nightly if you aren't already using it.

If not, would I be able to create a temporary 1080 version of the video and edit/position subtitles, and then have it scale properly to the 4K video version?

Yes. That's basically inbuilt feature of ASS subtitles. You should be able to simply mux the 1080p ASS file into 4K video and the player should detect and auto-scale.

[Ennio]

I was also wondering whether ASS subs needed "upscaling" to 4K resolution. Since SUP on UHD-BD are authored in 1080p also.
I think it depends on the player how to act with it.

[Vinnems]

I don't see why not. Try latest 64 bit nightly if you aren't already using it.

Oh neat, I didn't know others had carried on the legacy of it. I was using 3.2.2 still. Unfortunately, though, it didn't fix the issue, though I now know it's the codec (H265) and not the resolution (see below). This is my first foray into 4K UHD and the tech involved, and I'm finding a lot of other compatibility issues with it, too. Like VLC displaying everything in muted gray colors instead of vibrant colors...
Overnight I used Handbrake to re-encode the video as H264 at the same resolution and it opened fine in Aegisub. I'm now be able to do my subtitles, and keep the fancy formatting and have it match the final full quality video in terms of subtitle size. I was worried about what you were saying, Ennio, so that's why I re-encoded to the full resolution instead of just downscaling it. I did the re-encode over night so time wasn't an issue in this case.

[AbelMC]

I don't see why not. Try latest 64 bit nightly if you aren't already using it.

Oh neat, I didn't know others had carried on the legacy of it. I was using 3.2.2 still. Unfortunately, though, it didn't fix the issue, though I now know it's the codec (H265) and not the resolution (see below). This is my first foray into 4K UHD and the tech involved, and I'm finding a lot of other compatibility issues with it, too. Like VLC displaying everything in muted gray colors instead of vibrant colors...
Overnight I used Handbrake to re-encode the video as H264 at the same resolution and it opened fine in Aegisub. I'm now be able to do my subtitles, and keep the fancy formatting and have it match the final full quality video in terms of subtitle size. I was worried about what you were saying, Ennio, so that's why I re-encoded to the full resolution instead of just downscaling it. I did the re-encode over night so time wasn't an issue in this case.

Respect to VLC player, The problem that I found is that it does not perform the decoding by Hardware correctly, the same thing happens to me in the Android version, I better change to MPC-BE (Not the original "-HC"). In this one the colors look good, in some cases it may be necessary to configure the internal or external filters and the hardware acceleration. On Android, now I use MXPlayer because the hardware decoding is better

[Norberto!]

Hi all, I think I have the same problem.
Aegisub gives me this message when I try to upload a video:
"yuv4mpeg: video is not in a supported format. FFmpegSource: unknown video color space"
Does anyone know what to do to fix the problem?
T.I.A.