@emmrecs @johnebaker @Scenestealer @SevCardy @browj2 @me_again

Hi Jeff.

Going back to your is the audio the problem theory. Could it then be a buffer under-run problem with the audio?

How are your audio buffers set and which driver are you using?

Could the variation be there? Here are my audio settings.

Hi John.

The only reason I caught it was I noticed the wing flex and remembered a lot of complaints on another forum about focus shift which on that particular product was more noticeable. Once I realised what was near the centre of the frame it didn't take long to check where the wing edge was in comparison to where the focus area would be. What is not known is how big that focus area is and what would trigger the focus to shift.

Ray.

@CubeAce

Hi Ray.

These are my current settings:

So, quite different to yours!

However, changing mine to match yours and, you're right, the audio problem with the original file is gone! Reverting them to what is shown in my screenshot, the problem returns. I need to experiment a little to see whether I can reduce those settings and still achieve smooth playback.

Incidentally, is it my imagination, or did ASIO use to be an option for the audio driver? If so, that might be why my settings are so relatively low.

Jeff

EDIT: these are the "lowest" settings I can get away with and achieve smooth playback of one those .MOV files.

Thanks Ray for pointing all this out to me!

@emmrecs

Hi Jeff.

As far as I'm aware with the direct sound setting you are using, the Magix ASIO must be in use but there is no way within MEP to adjust it. I say must be in use or the vst audio plug-ins within the sound mixer would not work and nor would the mixer when the wav driver is selected.

I only found Magix had an Asio Driver when looking for an ASIO driver when I reinstalled Cubase and found it in the selections option there. Eventually I found the fine tuning it needed to work accurately and competently within Cubase and those settings seem to stick within MEP and VPX as far as I can tell. The alterations I have made within MEP and VPX don't seem to alter those so I can only assume that it is like having another layer of settings placed on top of the base ASIO settings.

Here are mine.

Feel free to copy them and see if it helps. Not sure though as I'm not familiar with your MOTU sound card.

I can't confirm that because I can't get to it within MEP or VPX but it is working.

Since thinking about how I found it and changed the base settings to work (It seems a very competent ASIO driver.) I wondered if it could be accessed by opening Music Maker and low and behold, if you open Music Maker the ASIO driver appears on my main Windows task bar and can be opened and fine tuned from there.

Be careful of configuring your inputs and outputs to your card as there are more ways of getting it wrong than correct and end up with no sound on any program needing the ASIO driver. In one respect is resembles the free ASIO4ALL driver in its setup arrangement.

Ray.

I played John's aircraft landing video back in the latest version of (new, revived) MPC-HC. The video played back fine. I could not understand what you all were talking about. (BTW, I can see that the landing was "firm." As someone with an Airline Pilot Rating myself, I presume that the runway was "short" and the pilot did not have the luxury of "greasing it on?")

Then I played it back in MEP 2021 and saw one of the roofs of a building jump back. (The building with the corrugated roof.) Update: That was with "Enable Smooth Playback" checked. Unchecking the blue lightning bolt makes it better (35/35) but I can still see where it wants to jump back at the corrugated roof.

So then I played it back in VLC. It didn't seem as smooth as in MPC-HC. But if there was jump back, it wasn't obvious, like it was in MEP.

(I add that VLC has never been totally smooth for me. It noticeably stutters with 4K. I was using 5K player for smooth playback of 4K vid until I discovered that MPC-HC was back.)

@CubeAce

Hi Ray.

No worries about the settings for my MOTU interface; it's actually the MOTU 8pre (original version, firewire connection) external interface which has its own independent control panel for Sample Rate and buffer settings so any changes made by VPX/MEP are not reflected in that panel.

That screenshot of the Magix panel is the one I see in MusicMaker. (It's actually a derivative of the full ASIO4ALL CP.) I was certainly not aware it was also used in VPX/MEP.

You learn something new every day!

Jeff

@johnebaker

There have been at least two if not three updates since this version, the current non Beta version is 27.20.100.8935.

I've updated to the latest non-Beta version (which is now 27.20.100.9030), but it makes no difference.

Sev.

@Scenestealer

So can we be clear that you are seeing this on an exported clip in say a media player, or in MEP if that exported clip is dragged back into the timeline?

Yes, in fact I originally discovered the problem when playing back Blue Ray disks burnt from MEP on a stand-alone Blu Ray player (i.e. not using any software on my computer at all). I must confess that in all my testing since then I have been using "Encode to directory" rather than burning throw-away coasters, and playing the resulting files using VLC.

I have just tried dragging back one of the exported files into the timeline and playing it from the timeline USING THE H630 (which has performed flawlessly throughout, it's only the Nvidia that causes problems). That was an eye-opener because you can then single step frame-by-frame using the arrow keys. In the first minute and a half of the video there are 7 "jump-back" glitches ALL of them corresponding to the start or end of a slow cross-fade between clips in the original project. I hadn't noticed exactly where these were happening before on playback in VLC because this section of the video has several very similar scenes slowly cross-faded to appear in the finished video as one continuous shot. It is also apparent by single-stepping that in 4 of these glitches the jump-back is immediately followed by the same image being displayed for several frames (11 frames in two cases and around 21 in another - I forgot to count the fourth). The effect is like a play-back that is repeating frames because it cannot read the next file quickly enough, but surely this shouldn't happen when exporting because there are no time constraints (i.e. if the file is not ready it should just wait for it and then continue).

Sev.

@pmikep

Hi

I will have to test MPC_HC. Thanks for testing and pleased you saw the jump back.

Runway was about 2100 m long and is well known for hard landings - so yes no chance of greasing it.

@emmrecs, @CubeAce

Jeff - Direct sound was the default.

. . . . the Magix ASIO must be in use . . . . I was certainly not aware it was also used in VPX/MEP . . . .

It was in MEP MX however, AFAIK, this was dropped with MEP 2013 - certainly there is no further mention of it in the 2013 or later manuals.

Vegas products do have the ASIO driver capability for audio.

John EB

@Scenestealer @SevCardy @browj2 @emmrecs @johnebaker @me_again

Now with Sevs' feedback is it possible that this then becomes a GOP structure problem?

Doesn't the manual state that in certain circumstances that frames may not be cut at exact points due to GOP constraints? Could this be an exaggerated version caused by the varying amount of frames at any one given time and the possible lack of frames is causing a glitch with not having enough of the correct frame types to hand to work from? Forcing the program to use previously used frames to fill the gaps? Why are there these differences between my CFR files and Johns' VFR example?

Or am I barking up the wrong tree?

Ray.

@johnebaker

Hi John.

Whether recent MEP manuals refer to it or not I'm convinced it needs to be in use to control the sound buffers better for reduced latency and stability when using the Wav Driver within MEP. It is a layer upon the existing Windows Audio Session API (WASAPI) that allows 32bit floating point and above audio to be used. It is difficult to run an external sound card without it well. ASIO4ALL gave that same amount of control over inboard audio chips for Cubase initially when my Terratec sound card no longer had 64 bit updated driver support. I thought the resemblance of the Magix Low Latency ASIO driver bore more than a passing resemblance to ASIO4ALL. Since I had altered the base settings for that ASIO driver for Cubase I have had no further problems within MEP and its audio buffer settings and have been able to keep those buffers lower than I previously had been able to.

If I'm wrong it wouldn't be the first time but my changes seemed like an improvement to me. Of course it could all be a software placebo effect on my part. I'm willing to accept that.

Ray.

Runway was 2081 m long and is well known for hard landings - so yes no chance of greasing it.

That's not short, but it also depends on the weight of the aircraft. (How much fuel still on board, pax load, etc.) The standard "short field" technique is to throttle to idle before the runway and pull the nose up to decelerate. (Which is exactly what the pilot did.) It usually results in an "aircraft carrier" type landing, where we're just trying to get the plane on the ground so that we can begin braking action. (Which he also did right away.)

I watched the video again, and it also might have been that the pilot was trying to make the mid-field taxiway, so that he didn't have to taxi back around to the terminal.

But he didn't make it.

@CubeAce

Hi Ray

CABAC is a lossless compression option within the h.264 codec and as we know mobile devices will take maximum advantage of compression to squeeze the file sizes down, hence it is not used.

. . . . Now with Sevs' feedback is it possible that this then becomes a GOP structure problem? . . . .

Possibly, especially if it is Long GOP video - I went to check back on @SevCardy posts and we do not appear to have asked for a vital piece of information re the source videos - a MediaInfo analysis.

Sev can you do a MediaInfo analysis of one of the original source videos, not the exports you have made, that show the jump back behaviour and post the results from the Text view please.

@pmikep

Yes he did take the long route - the funniest thing though is the only flight that I cannot remember what the aircraft was!

John EB

@johnebaker

Here is the MediaInfo analysis for one of the original source videos that causes "jump-backs" on cross-fades. I wanted to upload it as a text file, but that appears not to be possible, so apologies for the long post and the strange formatting:

General
Complete name                            : D:\My Videos\Farewell Concert\Space.mp4
Format                                   : MPEG-4
Format profile                           : Base Media
Codec ID                                 : isom (isom/iso2/avc1/mp41)
File size                                : 19.7 MiB
Duration                                 : 25 s 67 ms
Overall bit rate mode                    : Variable
Overall bit rate                         : 6 604 kb/s
Writing application                      : Lavf56.4.101

Video
ID                                       : 1
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Format profile                           : High@L4
Format settings                          : CABAC / 4 Ref Frames
Format settings, CABAC                   : Yes
Format settings, Reference frames        : 4 frames
Codec ID                                 : avc1
Codec ID/Info                            : Advanced Video Coding
Duration                                 : 25 s 0 ms
Bit rate                                 : 6 613 kb/s
Width                                    : 1 920 pixels
Height                                   : 1 080 pixels
Display aspect ratio                     : 16:9
Frame rate mode                          : Constant
Frame rate                               : 25.000 FPS
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive
Bits/(Pixel*Frame)                       : 0.128
Stream size                              : 19.7 MiB (100%)
Writing library                          : x264 core 142 r2389 956c8d8
Encoding settings                        : cabac=1 / ref=3 / deblock=1:0:0 / analyse=0x3:0x113 / me=hex / subme=7 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=48 / lookahead_threads=8 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=3 / b_pyramid=2 / b_adapt=1 / b_bias=0 / direct=1 / weightb=1 / open_gop=0 / weightp=2 / keyint=250 / keyint_min=25 / scenecut=40 / intra_refresh=0 / rc_lookahead=40 / rc=crf / mbtree=1 / crf=21.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / ip_ratio=1.40 / aq=1:1.00
Language                                 : English
Codec configuration box                  : avcC

Audio
ID                                       : 2
Format                                   : AAC LC
Format/Info                              : Advanced Audio Codec Low Complexity
Codec ID                                 : mp4a-40-2
Duration                                 : 25 s 67 ms
Bit rate mode                            : Variable
Bit rate                                 : 2 273 b/s
Maximum bit rate                         : 128 kb/s
Channel(s)                               : 2 channels
Channel layout                           : L R
Sampling rate                            : 48.0 kHz
Frame rate                               : 46.875 FPS (1024 SPF)
Compression mode                         : Lossy
Stream size                              : 6.96 KiB (0%)
Language                                 : English
Default                                  : Yes
Alternate group                          : 1

(The audio track is actually deleted in the project as it was not needed)

Sev.

@SevCardy

Hi

Thanks for the MediaInfo data - nothing stands out as being odd with the video, however it raises a few new questions

Is this an original recording - screen recording perhaps? - or has the original been processed with FFMPEG to mp4 format possibly to give a Constant frame rate?

What was the recording made with?

Is the D: drive an internal drive or USB drive if USB - USB2 or 3?

I have found on other forums that some users have been having the same issue with similarly encoded video and other video editors.

John EB

@johnebaker

Unfortunately this video (as with several others in this project) is not my own and I have no information about how it was created or any subsequent processing before I obtained it. My D: drive is an internal SATA HDD. It is 66% full but according to Windows 0% fragmented. I'm quite prepared to believe that the source videos are the culprit, but I had seen jump-backs in a test project where all the source videos were my own (and copied off the camera media without any post processing) but I think that was immediately after having problems with this project and without doing a clean boot first.

And I reiterate that everything works fine if I use the H630 GPU, so whatever the problem is, it is definitely related to the way the Nvidia is being used (either by MEP or Windows).

Sev.

@SevCardy

Hi Sev.

This may be extreme but do you want to eliminate one problem from the equation?

Try the Intel GPU diagnostic Tools.

Ray.

When I upgraded to MEP 2021, I reached for my go-to project to test it - it's an experimental project I started several years ago that uses videos from various sources and much more effects that I would normally use. It doesn't represent my normal type of work with MEP, but has proved useful for speed tests and in testing that features still work after MEP updates. It also has the merit that the total video is quite short. But as several of the source videos are not my own, I cannot vouch for their pedigree. So it was not the best choice of project to use for trying to tie down where the problem lies.

So, I today decided to go back to basics and create a new project from scratch (Full HDTV 1080p 25fps), and drop a single source video into it that is one of my own, shot in January this year and copied straight from the camera (i.e. no other processing beforehand). That played back correctly from the timeline (and on checking the log, there were no errors being reported), so I tried single stepping through forward and backward (using the arrow keys), fast play (ctrl-arrow keys), and "scrubbing" backwards and forward (dragging the play marker in the timeline) until suddenly, a jump-back appeared. As I replayed it several times, it got much worse and jump-backs appeared elsewhere in the timeline. I looked at the log and there were multiple occurrences of the following two lines:

2020/12/15 15:13:23 [FATAL]   [MXMPEG2 frame request]: GetMXVideoFrame: decode error 0x85008002 means <MXMPEG2 Error 0002: common decode error>
2020/12/15 15:13:23 [FATAL]   [Import]: VideoReader_GetFrame: ERROR GetMXVideoFrame FAILED

I could get these messages to appear at will by jumping to the start or end of the video, or by just clicking to set the playback marker in the middle. Then it got really bizarre, as I noticed that just switching focus away from the MEP Window and immediately back again, would produce these lines multiple times too - without doing playback at all.

Worse, if I exited MEP, restarted it, and created a new project and just dropped the same source video in the timeline without playing it, these errors now appeared immediately in the log. The same happened after a restart of Windows. But after CLOSING DOWN Windows and restarting, MEP reverted to the same behaviour as initially, i.e. no error messages until I forced jump-backs to appear.

This seems to point to some kind of hardware cache or buffering problem as it persists across restarts, but not across a complete shutdown.

I am now completely confused, and I'm going to go back to using the H630 - which, needless to say, copes with the same clip perfectly.

Sev.

For completeness I give the MediInfo for the source video below. I should add that I tried the same experiment with other source videos and also tried muting the audio, with similar results.

General
ID                                       : 0 (0x0)
Complete name                            : D:\My Videos\2020\2020 Uganda\20200116-080604.MTS
Format                                   : BDAV
Format/Info                              : Blu-ray Video
File size                                : 14.2 MiB
Duration                                 : 8 s 165 ms
Overall bit rate mode                    : Variable
Overall bit rate                         : 14.6 Mb/s
Maximum Overall bit rate                 : 18.0 Mb/s
Recorded date                            : 2020-01-16 08:05:57+02:00
Writing application                      : Panasonic

Video
ID                                       : 4113 (0x1011)
Menu ID                                  : 1 (0x1)
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Format profile                           : High@L4
Format settings                          : CABAC / 2 Ref Frames
Format settings, CABAC                   : Yes
Format settings, Reference frames        : 2 frames
Format settings, GOP                     : M=3, N=12
Codec ID                                 : 27
Duration                                 : 7 s 720 ms
Bit rate mode                            : Variable
Bit rate                                 : 13.7 Mb/s
Maximum bit rate                         : 16.8 Mb/s
Width                                    : 1 920 pixels
Height                                   : 1 080 pixels
Display aspect ratio                     : 16:9
Frame rate                               : 25.000 FPS
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Interlaced
Scan type, store method                  : Separated fields
Scan order                               : Top Field First
Bits/(Pixel*Frame)                       : 0.263
Stream size                              : 12.6 MiB (88%)

Audio
ID                                       : 4352 (0x1100)
Menu ID                                  : 1 (0x1)
Format                                   : AC-3
Format/Info                              : Audio Coding 3
Commercial name                          : Dolby Digital
Codec ID                                 : 129
Duration                                 : 7 s 744 ms
Bit rate mode                            : Constant
Bit rate                                 : 384 kb/s
Channel(s)                               : 6 channels
Channel layout                           : L R C LFE Ls Rs
Sampling rate                            : 48.0 kHz
Frame rate                               : 31.250 FPS (1536 SPF)
Compression mode                         : Lossy
Stream size                              : 363 KiB (2%)
Service kind                             : Complete Main

Text
ID                                       : 4608 (0x1200)
Menu ID                                  : 1 (0x1)
Format                                   : PGS
Codec ID                                 : 144
Duration                                 : 7 s 256 ms

@SevCardy

Hi Sev.

MPEG2 frame request ???.

Can we have a complete MediaInfo readout of the data from that source file please?

Ray.

@CubeAce

Hi Ray. I think our posts crossed....

MPEG2 frame request ???.

Yes, I wondered about that. Those messages are identical to the ones I got with the other project too. Of course, it could just mean module #2 of some Magix MPEG modules.

I was also surprised to see different durations in different sections of the MediaInfo - is this normal?

Sev.

@SevCardy

Hi Sev.

Have no idea about your first point as I have never experienced the same messages. For the second point.

No I don't think that is normal if constant frame rate. All my OBS files show same length periods for video and audio. Could be normal for VFR though, almost expected if you think about it.

Ray.

@SevCardy

Hi

From the tests is sounds like the cache file has become corrupted - this can occur if you jump around the timeline too fast playing one section then skipping to another in a series of quick moves due to the PC not keeping up with clearing the cache and starting rendering another section.

With MEP closed - in the folder(s) where the source videos are located, delete the file mxfilerelatedcache.mxc2

HTH

John EB