Lossless export issue

Alan_R

Borate - last discussed this issue with you October 2020 and having reread the topic its not clear whether it was concluded or not.

I am again attempting to do the same task, namely to quickly combine several mp4's into one mp4. (Quickly)

It does not work for some reason, despite my best attempts at ensuring all parameters are unchanged.

I think I can see whats causing its failure, but cannot see how to cure.

As a side issue I cannot find the lossless drop down list set as referenced in the documentation.

"There are three options in the lossless export drop-down list.

Auto Detect - This is the default setting. If the majority of your video does not need to be re-encoded, it will automatically be exported with the lossless setting. If the majority of your video needs to be re-encoded, lossless export will not be used.
Use Lossless Export - When this setting is selected, if your video meets the criteria for lossless editing below, lossless export will be used. Only portions of the video that need to be re-encoded will be re-encoded, the remainder will use lossless export.
Off (Re-encode Video) - When this setting is selected, your entire video file will be re-encoded. Lossless export will not be used."

Trying to achieve lossless export as advised, Export Video/lossless video - I get the window and select Local Computer - after a couple of seconds I get the Export file settings window.
Set the destination folder
presets are grey out (implying they cannot be changed which I understand)
resolution is greyed out (understandable as changing this would require re-render)
Frame rate is greyed out, as again change would force re-render BUT the greyed out state shows variable frame rate, when I have ensured all were created fixed.

1) this surely would violate lossless prerequisite?

2) as greyed out I have no chance to change

3) why is it greyed out implying it's following the trend of the constituent files, which have all been rendered fixed rate 50fps.

I think because it seems to be going for variable frame rate is why its fails lossless export prerequisites?

I do not need to economies of variable frame as my lovely new LG smart TV is so stupid it can't handle Variable frame rates, but I live with that.

Would welcome your thoughts please.

Alan

borate

The version to use now for lossless video is here. Don't use an 11.0x release at this time.

Lossless requirements are listed here. Resolution and framerate, mode, and file type are normally specified by the program, based on content.

To see the dropdown box click the blue Default Quality / Filesize link...

In tests here, an AVI 30.00fps file exported losslessly as an AVI at that fixed rate. An mp4 variable exported as variable. Let's take a look at your project.

Upload it and someone will check it out. The process is easy, quick and can be done privately. Just follow these steps...

Back up --- With your project on the timeline, click on MENU at the top-left. Click FILE|BACK UP PROJECT FILES TO FOLDER. Choose a folder and SELECT FOLDER.
Upload --- Use a free server - Google Drive, MS OneDrive, etc.* - to upload the saved, numbered FOLDER. Do NOT upload the individual VPJ or export file.
Get link --- Get a public link. If using Google Drive click GET SHAREABLE LINK. If necessary change "restricted" to "anyone with the link can view"
Share --- Click COPY LINK | DONE. Paste that link here, or click the folder at the top-right of this forum to message it privately to me. It won't be shared.

* Before uploading, right-click the folder, click PROPERTIES. Look at the File Size to confirm that it's not too big for the free space on the server.

Alan_R

My present version of VP is 10.96 pro.

I see the mp4 encoding window but note the Lossless export field is greyed out, does this mean it will be doing lossless export because the input files have met the criteria?

I see no mention of frame rate yet the Export video window still shows it greyed out and Variable. Does this tell us anything?

PS what is the simplest was of embedding small jpg into this message, like you have above, to help illustrate.

-0-0-

Another observation

Until now I have been playing with small mp4 for speed

I just loaded two large mp4 files, the first with a playtime of around 8min and the second around 4min.

I then went for lossless export, changed no setting.

Interestingly the export ran fast for about two thirds of the way through, then went very slow and I cancelled if after a minute and it was still only a fraction further through the exercise.

Curious.

-0-0-

You say framerate is normally specified by the program. Having input some fixed frame rate mp4, where/why does the program decide to apply variable frame rate, and surely this will invalid the criteria for lossless export?

borate

To include a screenshot, upload to a server, get a link and post it. To see what you see please upload the small test mp4 project, as instructed above.

Recall that there may be a difference in how the program handles lossless when applying it from the toolbar or specifying it from the export box.

Often, export will vary in speed as the program decides what it can and cannot render losslessly. Can't say how that or the framerate mode is determined. But if the export goes very swiftly as contrasted to re-encoding, it was mostly lossless.

Testing an mp4, when lossless was chosen from the toolbar, it was greyed out in export. If Video File export, all options were active in the drop-down box..

Alan_R

Right - have just uploaded 2 mp4's, one small one and one large one.

Both were created by VP and I believe they are both identical as far as Lossless processing is concerned, except of course for size.

When both dropped in for lossless export, the large one renders fastest at a few seconds, the small on takes considerably longer, irrespective of the order on the timeline.

Is it perhaps a case that big files always (where possible) get the lossless treatment, whereas small ones always get rendered because there's little to be gained from giving them the lossless treatment?

The link to the small mp4 https://drive.google.com/file/d/1ZQ80MWxycmnDo9Su71Uoo-bzvL6AwecW/view?usp=sharing

The link to the large mp4 https://drive.google.com/file/d/12hy70SoFixLwWvp9yFlx3dVHjqF09Zxm/view?usp=sharing

borate wrote:

Testing an mp4, when lossless was chosen from the toolbar, it was greyed out in export. If Video File export, all options were active in the drop-down box..

agreed.

-0-0-

More playing and strange results

I have 3 files A=30s B=4:04s C=4:44s

Lossless export A B and C

A renders slowly, B renders slowly, C renders very fast

Delete C from timeline

Lossless export A and B only

A renders slowly, B renders very fast

Strange...

+++ render was taking longer than realtime

borate

With a 64-bit version and the long file first on the timeline, export progressed at a uniform rate and completed in 12 seconds when LOSSLESS was chosen from the toolbar button.

When instead Auto Detect was specified in the export drop-down menu, it took 32 seconds and was slower for the short clip. Variable outcome in both instances.

As mentioned earlier, clicking the LOSSLESS button vs. using Auto Detect (or Lossless) from the export window are handled someone differently.

Alan_R

Thanks for your input

I will recheck my own timings for my two files you exported and report back. They sound so much nearer what I would expect.

Am I correct in assuming that Lossless export will always be performed when mp4 clips are apparent (or at least when they constitute a majority) and the requirements are met? But having reread the criteria I can see why it would never apply to any new edited work, but would must likely apply when combining smaller parts (already rendered) of a larger project.

I think we may have been unfamiliar with our brand new LG Smart TV and variable may not be an issue, but even if it were, simply matching your export times would be satisfying.

I run VP v10.96 Professional on 64bit Windows7 PC with 16GB ram, so would like to think that was not an issue.

borate

No definitive answers for you.

Allegedly the difference between the LOSSLESS button and Auto Detect (or lossless via the export window) is the percentage of the duration that lossless is performed.

It's unclear why that is or how it's judged, but testing both methods should yield results similar to those seen here.

Lossless will not be implemented on clips that the program detects do not meet the criteria.

Alan_R

Working with our test pair you have, produced an interesting fact

Large + Small on timeline - combined lossless run = 27s

Small + Large on timeline - combined lossless run = 27s

Large only - lossless run = 12s

Small only = lossless run = <2s !!!!

Suggests some 'join up' issue? Curiously a combined total not a million miles away from yours.

When I previously tried more than 2 files, there generally was one fast and the others slow.

Amazingly impressed by the speed of the large one, alone or combined!

Any further thoughts?

Thanks

Alan.

Alan_R

Just to bring you up to date - I've done the 'bolting together' the old fashioned way, ie without the use of lossless. I did go out so have no idea how long it took but it took over 10 minutes to stitch the 9 parts into one 27 minute final video. It works just as required , even our not so dumb LG Smart TV is quite happy with the end result.

It is likely the time spent searching for a solution has exceeded the extra time working without lossless operation, but from your feedback a solution does not seem imminent.

I would like to see someone (maybe tech team) pursue this issue further as clearly there are some oddities that need resolving, but for the time being I am happy file this exercise, and to thank you very much for your efforts. Sorry this is the second problem I bought you that got no solution, I'll try and stick to the blindingly obvious snippets you love to amaze me with!!

All the best

Alan.

borate

If you make the effort to upload the entire project, someone here will export it losslessly for comparison. There appears to be nothing amiss with the lossless function in version 10.96 (64-bit). But that mode is picky on what it will accept.^_

Sharing of the project (not the export or the VPJ file alone) isn't difficult. Just follow these steps...

Back up --- With your project on the timeline, click on MENU at the top-left. Click FILE|BACK UP PROJECT FILES TO FOLDER. Choose a folder and SELECT FOLDER.
Upload --- Use a free server - Google Drive, MS OneDrive, etc.* - to upload the saved, numbered FOLDER. Do NOT upload the individual VPJ or export file.
Get link --- Get a public link. If using Google Drive click GET SHAREABLE LINK. If necessary change "restricted" to "anyone with the link can view"
Share --- Click COPY LINK | DONE. Paste that link here, or click the folder at the top-right of this forum to message it privately to me. It won't be shared.

* Before uploading, right-click the folder, click PROPERTIES. Look at the File Size to confirm that it's not too big for the free space on the server.

Alan_R

Thank you, but I am

a) a bit busy right now and
b) it works, albeit a tad slower than hoped
c) perhaps more significant the project files total around 175GB give or take
d) and would take an age uploading @ 10meg

OOps just noticed Google drive space sits at 15GB, making my 175GB laughable.

My lossless use is infrequent and I always hope to get a Borate instant gem that solves the problem, but I guess in this case it is not to be.🙂

Thank you

borate

Your long file was duplicated to 27 minutes in length, then exported losslessly. That took :44.

The result was a 1920x1080 video. Likely about the best one might expect.

Glad it worked out for you.