Quality loss with PNG exporting at different resolutions?

[Adamx]

Hello. I'm new to these forums and grateful for your help.

I'm making a video comprised of many different clips and they're all at different resolutions and bitrates. Including 240p, 360p, 480p, 720p,1080p and 1440p.

My question is if I export my project as PNG lossless in 1440p, will the quality for all of the clips remain the same? I don't understand how lossless works when the software would maybe be changing the resolution of some of the clips too.

The answer to this will determine whether it's a good idea for me to sometimes export some chunks of the project as PNG then put them back into the project to keep working on them. Or if this will introduce some reduction in quality then I think I mustn't do this but convert chunks to sprites instead and copy and paste that? (Exporting all as PNG helps the preview be smoother and runs faster than the sprites filled with many different short clips)

Thanks for any advice.

[KarMa]

If the original resolution isn't 1440p, and you are upscaling these to 1440p, then there might be some quality loss in the upscaling. PNG also only support RGB, while most video is YUV (usually YV12) so there will be minor losses there. I would suggest using something that supports YUV like Lagarith, FFV1, or the fast Ut Video Codec.

[Adamx]

Ah I see thanks. So I think instead with all these many small clips I have I will make them into sprites and copy and paste them between projects to move them around. Are sprites lossless?

[KarMa]

Are sprites lossless?

If you are talking about converting YV12 video to RGB only PNG, then there will be rounding errors in the conversion. So not lossess. But that should be minor. If it's RGB to RGB PNG then there should not be any loss, but you will rarely ever find RGB video.

[Adamx]

I mean in the software if you have many small clips like 100 clips of video, you can select all of them and right click and press "convert to sprite" and it puts them all in one thing. But you can double click that and see each clip inside there. Though I'm also unsure if that "conversion" into the "sprite" does anything to reduce the quality because it seems to make it run much faster to move them around and even to play them back

[KarMa]

What program are you using and what exactly are you trying to create with your videos? As it's not really normal to be using sprites for video editing unless you want a small stagnant image on screen on top of other footage.

[Adamx]

Oh it's called vsdc I thought this was a vsdc forum lol. I googled that and went into the first site..

[KarMa]

Outputting PNG images is probably the best option as that program seems to have a very limited video format support. You'll take a small color accuracy hit when it's first converted to PNG but after that it will stay lossless until you convert it to something else like YV12 H.264.

[Adamx]

Thanks very much for your advice

[Cornucopia]

Look at it this way: PROCESS and FORMAT. There are both lossy & lossless processes (and workflows) and lossy & lossless formats (both storage & transmission). Your outcome is always the combination of these.
PNG is a lossless format.
Resizing is a lossy process.

Scott

[Adamx]

Look at it this way: PROCESS and FORMAT. There are both lossy & lossless processes (and workflows) and lossy & lossless formats (both storage & transmission). Your outcome is always the combination of these.
PNG is a lossless format.
Resizing is a lossy process.

Scott

great advice. Thanks.



So I'm going to be keeping all my clips as they are in the software until the final product is ready to export. Then I'll be exporting at some different sizes 720p, 1080p and 1440p to see which looks best (since the project is comprised of all different size clips!) and apparently 1440p will be best for YouTube uploads anyway for more bitrate.

I found out that VSDC uses terminology in an incorrect way. "Sprites" in VSDC is like a way to group clips together. As someone new to this kind of thing it confused me trying to search about this use of "sprites" online but I think it doesn't affect the clip or the quality in any way in VSDC to use this.


Thanks everyone.