Clarification on Proxy Files

Craigster wrote on 5/20/2021, 4:00 PM

A video I posted this week to Facebook and to Youtube (from the same export file) got me different results this week (whereas the same process got me the same results the prior two weeks). The issue was that in Facebook, the video wants to default to SD rather than HD, and when manually changed to play HD, the audio and video are no longer aligned. Varying results on different computers, browsers, and locations. Youtube of the same file: rock solid and HD in all tests.

I noticed this week when I was loading files into the timeline that they were taking much longer than normal, and noticed that Proxy files were being created. I must have inadvertently checked the "automatically create proxy files" option. The audio files were specifically labeled as proxy. (Interesting, as audio files as so much smaller comparatively, I would have thought that proxies only applied to video files).

On another forum (not Magix), someone mentioned that when using proxy files, you need to replace the proxy audio files with original files before export, to not export the proxy files. So, I came here looking to see if an extra step needs to be taken within VPX prior to exporting.

I did see this conclusion made and affirmed on another thread here: "So the proxy files have nothing to do with exporting . . . ."

So, I understand that proxy files are utilized for smoothing performance while editing on large projects or underpowered systems.

I would just like extra confirmation on a few questions, as I'm planning to UN-check the create proxy files option.

1. Under what specific conditions are creating proxy files considered to be beneficial?

2. Could the usage of proxy files have contributed to the out-of-sync result by Facebook's compression scheme?

3. Is there anything that needs to be done on a project utilizing proxy files prior to export (i.e. replacing audio proxy files with the original audio files)?

Many thanks!

Craig

Comments

CubeAce wrote on 5/20/2021, 6:29 PM

@Craigster

Hi Craig.

Have you read your manual page 233 on the subject of proxy files, when they could be beneficial and how to avoid using them for export?

How VPX and MEP behave depends a lot on how you set up the program and individual projects.

My guess is at some point you have changed your settings on the use of your proxy files or changed the way you have rendered a project and so far you have not explained any of your steps for anyone to comment on with enough conviction on what has caused your problems.

Read the page and check your settings. If you then still don't understand what happened, come back with all the steps of your project setup settings and we will try to help you get a better quality of export.

Ray.

Scenestealer wrote on 5/20/2021, 8:04 PM

@Craigster

The audio files were specifically labeled as proxy. (Interesting, as audio files as so much smaller comparatively, I would have thought that proxies only applied to video files).

This is not to do with the size of the audio or video file but to with the complexity of the compression algorithm used, and as such a highly compressed audio file will be converted to an uncompressed .wav file in the proxy creation.

Interesting that Magix, who come from an audio editing background, put quite a lot of emphasis on the load that audio files can put on the system during preview and give you ways to adjust the audio buffer sizes and numbers.

Peter

johnebaker wrote on 5/21/2021, 3:49 AM

@Craigster

. . . . The issue was that in Facebook, the video wants to default to SD rather than HD, and when manually changed to play HD, the audio and video are no longer aligned. Varying results on different computers, browsers, and locations. . . .

Assuming you mean an uploaded HD (720p) or FullHD (1080p) video, and are then playing it back from Facebook then, like Youtube, they deliver the video at a resolution/bitrate to suit your Internet connection speed or load on their servers - at high load times they will deliver a lower resolution version - there is nothing you can do about this.

If you force the download of a higher resolution then you can expect issues as the requested download speed cannot be met by their servers and the playback may begin to stutter, pause or in the worst case timeout, while sufficient data is downloaded to continue.

John EB

Craigster wrote on 5/22/2021, 12:18 AM

@Craigster

Hi Craig.

Have you read your manual page 233 on the subject of proxy files, when they could be beneficial and how to avoid using them for export?

How VPX and MEP behave depends a lot on how you set up the program and individual projects.

My guess is at some point you have changed your settings on the use of your proxy files

Ray.

Ok, So I did have the box checked to automatically create proxy files. I've only worked with them once before, years ago, and don't have a great understanding of all the options. Thank you for the manual tip. I read all the info there and see where settings are made. So, it appears that VPX did export at default proxy settings, which are lower than my normal export settings.

Craigster wrote on 5/22/2021, 12:23 AM

@Craigster

Assuming you mean an uploaded HD (720p) or FullHD (1080p) video, and are then playing it back from Facebook then, like Youtube, they deliver the video at a resolution/bitrate to suit your Internet connection speed or load on their servers - at high load times they will deliver a lower resolution version - there is nothing you can do about this.

If you force the download of a higher resolution then you can expect issues as the requested download speed cannot be met by their servers and the playback may begin to stutter, pause or in the worst case timeout, while sufficient data is downloaded to continue.

John EB

Ah, this is helpful!

I think I haven't fully realized all 3 factors. I'm aware of my upload settings and my internet connection. But was not considering what FB might do to reduce delivery based on their server load. This would likely explain different playback results at different times.

So, if FB is defaulting to SD, it may well be that this is what FB's playback service can optimally provide at the moment? Wow, that stinks! But, I guess I like to be in the driver's seat. So, one more plus for YouTube compared to FB. And big plusses to Vimeo and other true video sites that play what we give them.

CubeAce wrote on 5/22/2021, 12:45 AM

@Craigster

Several companies including YouTube made a statement several months ago that they would do this due to the increased demand of their services during the pandemic as the extra demand was was close to taking down the internet infrastructure during peak use. Facebook just tends to do it more due to amount of inane short uploads that platform suffers.

Ray.

Craigster wrote on 5/24/2021, 11:21 PM

@Craigster

Facebook just tends to do it more due to amount of inane short uploads that platform suffers.

Ray.

Yeah, the inane shorts clutter up the high-quality cat videos!