100 clip multi screen method

[deleted]

The largest layout for the Split Screen effect is a matrix of 5 x 5 meaning the maximum number of clips is 25, each clip being on a separate track. This number of tracks along with any effects/fades/transitions etc. can mean VP can struggle to preview. With multiscreen becoming popular I looked into ways of getting more clips to display without VP getting bogged down. 100 clips can be displayed in a 10 x 10 layout without using a split screen and all will play smoothly (at least on my old Vista machine they do.)

The basic idea is to load the first 10 clips into VP. Scale them all to 0.1 and then using the Position effect arrange them one under the other at the left end of the frame......

For each of these tracks the Horizontal position value is -45 The vertical values for each clip to line up under each other are...

-45
-35.3
-25.6
-16
-6.25
3.57
13.2
22.7
32.4
42.3

With the first 10 clips lined up and playing Export the clip (Default name Sequence 1)

Repeat for the remaining clips doing 10 at a time. This can be done relatively quickly if you select all the tracks and then set the Scale (0.1) and Horizontal position (-45) for the first clip and then Append the chain effect to all the other selected clips in one go. Then simply set the vertical positions for each track from the above list.

You will now end up with 10 exported clips (Sequence 1 to Sequence 10) each having 10 images one under the other on the left as shown above.

In order for VP to run without undue struggling we need to reduce these to 5 clips.
Open VP and load Sequence 1 and Sequence 2
Place Sequence 1 on Track 1 and Sequence 2 on Track 2
Add a Position effect to Track 2 and set the Horizontal value at 10 and Vertical to 0 Both columns will now be visible...
-
Check all the clips play and Export the timeline. Let's call it "A"
Repeat the procedure for the remaining 8 exports, a pair at a time and you will finish up with 5 videos. (Each having 20 clips like the sequence preview above named e.g. A; B; C; D; and E

To create your 100 video clip multiscreen load all 5 clips to VP. Place them on separate tracks and then apply the Position effect to each track to move each successive clip to the right and so revealing the one underneath. Use the following Horizontal positions from Track 1 to Track 5. to do this.. (Vertical for each is 0)
0
20
40
60
80
The result is all five tracks visible at the same time , each with two columns of 10 clips , making 100 clips playing at the same time.....

Since VP, in this last step has only 5 clips to render it doesn't struggle in the preview as it might do with 100 clips and 100 tracks. At the most there are only 10 tracks at the outset and even on my old slow machine it seemed to cope with ten 1080 16:9 mp4 clips.

Users might find this an useful way of generating larger multiscreen presentations than the 5x5 split screen and where individual clips with Scale and Position might struggle.

Nat

TomH

Nat, I wonder if your old Vista machine might be a then very good media machine with 7200rpm or faster drives, hot graphics card, etc. My contemporary i5 laptop struggles with 5 clips, and Sequence Preview becomes unusable above that. CPU utilisation seems to be the limiting factor in my case as there is plenty of free RAM and HD activity is not high. When CPU is at 100%, VP is up around 85% so, even if I could shift more to it, there's not much to be gained. And the GPU is just being tickled so the program is not taking advantage of it.

As a corollary to what you describe, I had conceived of using the quad-split, initially by stacking 4 quad sequences as clips in another quad sequence and so on: 4=>16=>64 and exporting when there were signs of bogging down. However, bogging began at the start of the second level with only one quad placed inside another quad and the startling realisation that the audio track of a sequence clip, while still audible, is invisible and uncontrollable. Your method, by exporting every sequence rather than stacking, assures that the audio mix from the sequence is visible when imported to the next level.

borate

While editing, close other programs.

Under OPTIONS | EDITING toggle "use hardware acceleration' to see if that has any effect.

Under OPTIONS | DISK, Clear Unused Cache Files.

Yes, try not to utilize multiple sequences, relying instead on Nat's suggestions.

If files are large very high resolution, consider using proxies.

TomH

The "hardware-accelerated video effects" option was already checked. Haven't looked into whether this laptop has the required SM2.0 hardware.

I have periodically cleared "unused cache files", as much as 25GB and this just a 3-minute project. And unclear what "unused" means - unused by the current project? Disk activity is not especially high so I wonder if there is a real benefit. Better that the cached files in use be defragged, maybe.

Not currently stacking sequences - that was just an experiment, a disappointing one.

I've only one high-res file for the main screen. All the splits are from small files. If the project gets into bigger problems before I finish, I'll try replacing the one big file with a proxy.

borate

If you upload your incomplete project someone here will check out how it runs on their hardware and perhaps make suggestions. The process is easy, quick and can be private. Don't upload the export - just the PORTABLE PROJECT, as instructed here...

http://nch.invisionzone.com/topic/23659-tips-for-getting-help-on-this-forum/

If it contains sensitive material link it in a personal message (PM). Click the envelope above. It won't be passed on or retained. Use FILE|SAVE PORTABLE PROJECT AS, not simply SAVE PROJECT, and don't forget to get a shareable, public link - not one that is restricted.

[deleted]

TomH

Windows Vista Home Premium 32-bit SP2
Intel Core 2 Duo CPU E4500@ 2.2GHz, 2.0 GB RAM
NVIDEA GeForce GT 730.

Nothing particular running in the background and it handles 5 mp4 1080 clips with sound with no apparent problems. (In the first exports for the multiscreen project each column had 10 clips, (i.e. used 10 Tracks, but still seemed to be OK) It was necessary to wait until all the tracks had cached and then checking the preview before each export. Each original clips were only about 30 seconds duration as this project was in the nature of an experiment so longer clips on my machine might possibly stutter.

Stacking Sequences........ Not sure why that didn't work for you, but it depends what you mean by "Sequence" The definition of sequence when referring to VP is misleading IMHO as it refers to the whole of the timeline contents and also the clip that is created of the timeline and stored in the "Sequence" bin.

OK..That IS a sequence but even though you might consider it a single clip, in relation to the 100 multiscreen project) it still references the 10 original clips (or the 20 original clips) and stacking 5 of these means that VP is essentially still trying to handle 100 tracks!

Exporting the timeline however, condenses the tracks into just one clip. In this last version (for reasons I won't go into) the default name becomes "Sequence (x)" which is confusing when he contents of the Sequence bin are also called "Sequence (x)"

So, If you are using the bin sequences for your stacking that might be the reason you are having preview problems. Try exporting the timeline and you will then only have a single stand alone clip

If you find mpeg4 clips are causing a problem have you tried converting them to mpeg2? I used to do this regularly when using early versions of VP and found that I rarely had Building Preview problems and the clips were much clearer and brighter..

The cache retains clips from all previous work, even when that work has been exported and even after VP is closed. The "unused" files are all the files apart from everything not in the current project. Retaining current files in the cache means that a project will load to VP and assemble more quickly than from an empty cache. Even if the cache is empty VP will load a project, but has to search for the files in the locations saved with the vpj file which can take longer.

Nat

TomH

Here's my portable project. Your observations of its performance on your hardware would be much appreciated. Mine is:

Windows 10 Home 64-bit (10.0, Build 18362)
Intel(R) Core(TM) i5-6200U CPU @ 2.30GHz (4 CPUs), ₂.4GHz
Intel(R) HD Graphics 520 with 128MB dedicated and 4041MB shared
RAM: 8GB
HDD: WDC WD10JPVX-75JC3T0 Cache Memory: 8.0 MB, 5400.0 rpm. SATA 6.0 Gb/s

One strategy for speeding up the process is, where possible, to split long tracks into separate sequences, provided one can work on them independently and then assemble them in another sequence. If building a preview cache essentially takes kt, where k is some factor and t is the playing duration of the sequence, building a preview of a half-duration sequence should take approx half as long as for a full duration sequence.

Tom

borate

What version is being used? If you have purchased within the past six months, use this version. Do not use v8.56.

Dropping sequences into sequences occasionally is useful, but the content of the initial sequence and the target are both in memory. To confirm this, drop Seq 1 into Seq 2, then attempt to delete Seq 1.

It's best to go with Nat's method of exporting, then reimporting what is basically a new clip with transitions and effects composited. That cuts down on processing.

This may all be moot when VP 64-bit is released, increasing program memory. No date for that, but it's being worked on diligently.

Your project played and exported fine as an mp4 at the 1280 x 720 45fps suggested settings on an I7 PC utilizing 32GB RAM and a midrange video card.

TomH

That project is just one sequence. Not to be confused with my initial test of a sequence of 2x2 sequence clips stacked in another sequence stacking them as 2x2. I'm well aware that everything in a sub-sequence is active.

My version is 8.35.

Is your Preview within VP of my project smooth? Thanks for trying it. Another warning of limitations being reached in my system is that a screenshot from within Preview of the sequence which has scrolling text on it did not include the text.

borate

Tom wrote: Is your Preview within VP of my project smooth?

Not a hitch, after about two minutes of caching.

[deleted]

Hi Tom

Your project failed to play correctly on my Vista machine in VP 8.56 which is a Beta version which I am currently looking at. This seems to be due to a major bug linked to the sound tracks and which has been reported. Switching back to Version 8.45 your project loaded and played just fine here. Looks and sound OK. As generated by your upload an export here did take some time but the result was excellent

The only minor quibble is that your singers don't all appear on screen at the same moment. 🙂 which I am sure was the intention. Checking out the individual clips it's probably because some were moving their heads/stooping/looking down etc right up to the point of actually singing. It's a good idea if, with these things if each participant starts filming and then pauses for a several seconds (say, 5 - 10s even) ...composed and ready to go ....and then starts singing to the audio. It then gives the editor some composed footage to line up everybody's audio and split all the tracks in the few seconds before they start. Now with clips grouped you can have them all fade in and out together.

I thought that was great and very stirring!

Nat

TomH

Thanks for the feedback, Nat, including the performance aspect. This was a spur of the moment project started less than a week ago, the music not sung in 3 years and the first self-recorded videos for most of the participants. So many challenges it discouraged most of the chorus from trying.

My video export takes about 3x playing time, as does building the Preview cache every time a change is made which really slows productivity.

Another issue is the quality of the ambient audio in the export. It sounds ok within VP, I think, but the export exhibits the artifacts of too many audio data compression-expansion passes or excessive data compression. I've not the time to explore further and fix that.

borate

Did you download the export from the link above? How did it sound? There are numerous export audio bitrate/quality options.

Made changes to effects on various tracks, which did prompt re-caching, but buffering was rare and playback smooth overall. Mp4 H264 export at the defaults took 3 minutes.

Your PC specs are adequate, so if results are sluggish then something isn't right.

Have your installer on hand, or download this version. Close VP, then use Windows Explorer (file manager) to delete all files in the following folders...

"C:\Program Files (x86)\NCH Software\Components". Or this may be in "C\Program Files\NCH Software\Components".

"C:\Users\<PC name>\AppData\Roaming\NCH Software\Components"

Install Videopad. This may not help, but it won't hurt.

Also consider unlinking and deleting audio tracks that are not being used.

Verify that video drivers and Direct-X are up to date.

AMD / ATI users: http://support.amd.com/us/gpudownload/Pages/index.aspx Intel users: https://downloadcenter.intel.com/default.aspx nVidia users: http://www.nvidia.com/Download/index.aspx?lang=en-us Update DirectX: http://support.microsoft.com/kb/179113

TomH

The audio stream is 192kbps AAC LC so the final encoding choice should not be the issue because it is a higher rate than the preceding. Rather it is the cascading of codecs from original capture of the ambient sound by the video recorder to the playout of my finished video. We know nothing about the video recorder - its audio encoding might be linear but might be MPEG. So one can imagine that the published version has had this minimum length chain of codecs:

Capture=>
Export=>
YouTube=>
Capture (Xbox Game Bar 128kbps 48kHz AAC LC)=>
VP Export (192kbps 48kHz AAC LC)=>
YouTube

The output of #4 sounds smooth while #5 (VP) has severe encoding artifacts. That may point to a problem with the codec used by VP or an unavoidable consequence of adding one more audio data compression codec in the chain.

Sorry that we have strayed far from the subject title - is there anyway to split it out?

borate

My hearing may be lacking, but the VP export played locally sounds solid - no severe artifacts.

TomH

borate wrote:

My hearing may be lacking, but the VP export played locally sounds solid - no severe artifacts.

I hear the distortion on your YouTube upload, same as what I ultimately published and what I hear on the VP Export. If you listen closely and do an A-B comparison between the H264 and MPEG-4 exports I referenced in Choice of video codec affects audio quality, you should hear the distortion introduced by VP's defective H264 without anything clouded by an upload to YouTube..