h265 issues

[RobertOZ]

Have Corel resolved the issues with importing H265 .mkv video
Corel state that I need to have Microsoft HEVC video extension installed in order to import h265, which I do, so that's not the problem and my graphics card is more than adequate

I can play h265 .mkv in VLC and WMP without an issue and the resolution on the 4k screen is magnificent, so why can't I import into VS 2018, when Corel tell me that I should be able to

It doesn't matter what type oh h265 file I try to import the result is the same, File Format Mismatch

[aljimenez]

I have troubles with .mkv files. A suggestion: convert the .mkv files to MP4-HEVC with .mp4

[Ken Berry]

I get the same msg as you you, Robert, with my HEVC .mkv footage (of which I don't have much). But the problem with Al's suggestion is that I also get that message with some of my other HEVC mp4 files, while others play but show only black!

Yet Cyberlink Power Director 16 accepts and plays them all properly without problem.

And for the record, I also have the Microsoft HEVC Video Extensions installed.

[RobertOZ]

Tried Als suggestion, used HD Video Converter Factory and converted to H265 for MP4, unfortunately, same result, File Format Mismatch

[lata]

Hi
Quick reply
All my h265 video show black yet play ok with my media players
Share to h265 and video studio tells me my pc cannot do the job.
Add h265 to timeline and messages allows me to match the project properties
Now share same as project renders ok, although shows black. Plays ok on pc
Well that was using bets 4 I think, now vs does not create a usable video, it flies through the render the file has no size at 0kb, vs shows as mismatch

[Charlie Wilkes]

From what I have seen, people are having lots of problems trying to edit HEVC on any hardware/software platform. Even if you can drag it into a timeline and have a powerful computer, it is laggy. Some are turning off SMT on their high-end CPUs to improve single-thread performance, because that seems to be the bottleneck.

Once again I think an intermediate codec may be needed, and Cineform is the one I know works with VS, for me at least.

It's interesting... a few years ago, people were dismissing intermediate codecs as obsolete. Now they are back with a vengeance.

[Ken Berry]

I haven't yet tried Cineform in this regard, though I have GoPro Studio on this computer for my Hero footage (just in case, since generally I have no problems editing that footage in VS).

But more generally, and in response to a question from RobertOZ in another thread, I've raised this thread with my Corel contacts, and will report back if or when I hear back from them.

[Charlie Wilkes]

Cineform was developed for early high-end digital cinema work, so it supports 10-bit color depth and 4-2-2 or even 4-4-4 chroma sampling. As far as I know, VS can handle all those attributes and pass them through when rendering.

I think this is the case, because I have had the problem of banding artifacts when I try to enhance 8-bit video. I can mitigate this if I edit in Cineform, because it has a broader palette to work with. Then I can export in Cineform with VS, and no banding artifacts. Unfortunately the artifacts usually return if I render to an 8-bit codec, but sometimes not as bad.

Cineform used to cost $100. GoPro bought Cineform some years back and released the codec as freeware with their editing package. Now they have released the source code. I think Corel would be wise to make the most of that, especially now that users are trying to edit HEVC camera output. My impression is that HEVC zaps mainstream hardware and is just not suitable for editing. It is ideal for packing lots of data into a relatively thin stream.

Instead of struggling to make VS work with HEVC, Corel could put out a transcoding solution, or adopt third-party transcoding solution, that intercepts the file and offers to transcode it to Cineform.

The downside is that intermediate files will be huge, especially if the frame resolution is 4k. I think that's just the way it goes if people want to shoot and edit 4k video with a 10-bit codec.

[RobertOZ]

Tried Als suggestion, used HD Video Converter Factory and converted to H265 for MP4, unfortunately, same result, File Format Mismatch

Whilst Magix Movie Studio Platinum 15 cannot play .mkv files, it plays the converted files fine, did notice that the first time I tried importing the files, it automatically added the necessary codecs