Blocky Aliasing added to Exported Video

[Dave Holmes]

Hi guys...

So after enjoying the trial version without problems on my Windows 10, 64 bit machine, I am having a really bad experience with Corel Video Ultimate. First it only rendered 3/4 of the video and completed the
remainder with a frozen frame and the remainder of the audio.

..that problem magically went away. how knows what caused that. The latest problem is that I just checked a 50 minute video I exported and there is blocky aliasing on the video export and also this appears in the preview window.

I am not processing the video in any way in Corel Video X10. so it is confusing the hell out of me. I opened the original video file in VLC and there is no Aliasing, so smart render should just save the original file data when it exports surely?. perhaps VLC has a more advanced codec that is correcting a flaw in the video on playback, something that Corel can perhaps not do.. I dunno. all I know is that when I render it looks bad. it is only in one section (happens to be the key section of my video). I am simply using Video Studio to stitch together all these sections of video, a short intro MP4, the main video of a concert 50 mins MP4, and two small outro and credit MP4s. Also an audio track I have lined up to sync with the video. When I export with 'same as project settings' I get the aliasing. it is really frustrating waiting a looooog time for a render to find it is flawed.

So , any ideas on causes / solutions would be welcome. While I wait for some potential solutions here, I need to crack on and finish this thing, so I am currently exporting that short section reimport to see if that works (probably will still have the aliasing!) failing that I could try import the whole video of the concert into Window Movies Maker or similar program and re export it all again to MP4 with the same length to sync to the audio. I would lose some quality I guess but if it means I can load into Video Studio without it creating Aliasing, it would be worth it.

Dave

[Ken Berry]

When I export with 'same as project settings' I get the aliasing. it is really frustrating waiting a looooog time for a render to find it is flawed.

This begs the question of what your project settings are. In Preferences > General, have you ticked the box beside "Show message when inserting first video clip in timeline"? If so, then when you started your project and inserted your first mp4, did you get a message asking if you want the Project Properties to match those of the clip? If so, then your project settings will match the original video exactly. SmartRender should then work and it shouldn't take too long to render -- although with a new audio track, this might make things longer.

I render quite a lot of my own GoPro mp4 and have never had any of the problems you mention in this thread and in your other one. You haven't given us any information about your computer, but my first thought when I saw your other thread about the break at 60% was to wonder if the computer might not be a powerful one and some other process was going on outside Video Studio which might have interrupted the first rendering. In that case I would have recommended using SmartProxy. This makes a standard definition copy ("proxy") of your high def original video. You edit that and at the end it is applied to the high def original. SmartProxy might also be used in the present case.

[Dave Holmes]

Hi Ken, thanks for the info,

The Project properties match the video. The GoPro footage was fine actually, but I was also using another camera, my Galaxy S5 which is set to the same video settings as my GoPro Hero as far I can tell. That camera footage was fine too, as I edited it all together in Video Studio X10 a few days ago and got it exported as a video fine (although I had to do it in two sections - start and end - as the video render stopped after 40 minutes due to another weird issue.. i had to export two halves and recombine in Avidemux). That weird export problem seems to have gone now... maybe corrupted temp files? who knows.

It was only on a small 30 second section of the S5 footage (out of the whole 50 minutes of combined footage) that had aliasing. I find it really weird, as I said, because the original video has no aliasing at all, and the MP4 it is happening on was the combined GoPro/S5 video which was actually exported from Video Studio X10 a few days ago. The aliasing occurs when there is movement and a lot of stage lights and smoke in the image and maybe that kind of 'image data' confuses it

I hope I have managed to fix it now ! (I am exporting as I type..it looks fine in the preview window). The way I fixed it was to opened up the uneffected MP4 file in Window Movie Maker and then I exported that tiny section that Video Studio didn't like. I imported it into Video Studio, zoomed right in and cut it exactly to the same length (although interestingly, Window's Movie maker somehow managed to make the clip a frame longer....which makes no sense to me) . Anyhow I just took a frame off the start to fix this. The replaced clip sits between two other GoPro camera clips so it was easy to cut. One I got it the same length and replaced the section exactly in the same position and deleted the old one. I noticed it is slightly different colours I would even say brighter than the original.. I guess that's down to the programming code of Window Movie Maker and codecs? Anyhow it seem to have done the trick. shame that I am finding all these things that Corel Video can't handle or seems to do in a strange or unefficent way. I am going to watch more videos and read the whole manual.. but my impressions of the Ultimate feels buggy. but once I learn all the issues, I can work around them until they are patched or improved. I still quite like the package, ..and a lot cheaper than Adobe Premiere =)

Dave

[Dave Holmes]

Well.. the section replaced turned out fine. The export has added random aliasing on other sections of the video now. If I don't find a solution I think I am going to have to purchase another video editor. I can't rely on this one

Here's the video , 3:55 is an example of the problem and it continues throughout. 3:11 to 4:15 is where I replaced the video with Windows Movie Maker render. looks fine. I don't have the energy or time to faff about doing that with my whole video. Video Studio Ultimate should be able to handle it. https://youtu.be/SkIXQ9j9-Hc

Dave

[Terfyn]

Have you got enough power in your PC? Saw the problem but it looked to me as if your computer could not handle the render. May be worth checking before you buy another VE and still get the same problem.

[Dave Holmes]

I have an i7-4790 CPU 3.60GHz, 12GB RAM, 64 bit Windows 10, 1TB HDD with an AMD Radeon R9 255, it should be powerful enough. I really don't think that is the problem either as it renders video perfectly without artifacts in crappy programs like Windows Movie Maker.

The trouble is that Windows Media Maker is useless at syncing, you can't keep things in time or drill down to frames very well at all. it's for crude edits and joining clips together. I just did a test and audio is slightly out of sync by the end of the 50 minutes or so. I can't use that.

Avidemux 2.6 is pretty good at joining files but can't do cross fades as far as I know. So I have tried to make a video of the sections cross fading and will stitch them together and hopefully attach the sound track to it in sync. :/

Or I have to go through every section of the 50 minute video that Corel Video Studio can't render and re-render it in Movie Maker like I did with the other section. and then export. I do have other plans for the remaining hours of my life though, so if I can find a way to just export the sucker without any problems I would prefer that

Dave

[MrJohnny]

The footage shot with the Galaxy S5 may be the culprit. You could use MediaInfo/GSpot to ascertain if it is variable frame rate. If so, convert to fixed frrame rate.

John

[JJLudemann]

See my thread below: http://forum.corel.com/EN/viewtopic.php?f=1&t=61827

I'm also using a Galaxy S5, with the same result. A fix is explained there, although I haven't yet tried the fix with full HD output.
MediaInfo >> Handbrake >> .MKV fixed frame rate >> VideoStudio

-JJ

[MrJohnny]

Hi

Double post?

Definitely worth a try converting the S5 footage to fixed rate.

John