Editing videos causes loss of quality and increase in file size?

[PeaceSells]

Hey guys,

 

I'm not experienced with editing videos. Everytime I record some gameplay in whatever game and do any editing, even if it's just to cut out the beginning or the end to make it shorter, when I save it using same format and similar quality level settings, the end result is always a bigger file size with lower image quality. It doesn't seem to be specific to the software used to record or edit, I've used different software on different occasions but this issue is a constant. Nowadays I use Nvidia Experience for recording, but in the past I've used OBS and FRAPS (that I remember from the top of my head) and for editing I've used VSDC and Movie Maker (that I remember from the top of my head). Nowadays I simply don't edit, in order to preserve image quality and file size.

 

In my limited understanding, the loss of quality comes from the compressing that's done at the time you save the file, so, in other words, you're compressing a video that was already compressed once when it was recorded and saved. All formats have their own compression and each time a video is saved it's inevitably compressed again (although file size seems to grow).

 

If I'm right, then this problem is inevitable... Please tell me I'm wrong...

Edited June 28, 2018 by PeaceSells

[ouPhrontis]

When you say similar quality levels, without knowing the specifics that is probably where the change, loss etc is taking place, edited files should be done lossless at first until you're satisfied with the result and then (if any) apply compression, there are so many levels of compression for just one file format that without knowing the specifics it's hard to tell where it's happening for you.

 

The issue with editing in lossless is that it will start to consume large chunks of storage space as you keep cuts/separate chops of files.

[Johnny_Rico]

try using x264 format for encoding the output edited file

eg I take a 4G fraps recording and encode it using x264 now it is 300MB quality is damn good

[PeaceSells]

When you say similar quality levels, without knowing the specifics that is probably where the change, loss etc is taking place,

 

I guess you're right, the quality of the recorded file by Nvidia Experience is pretty good, but I don't know what the settings are exactly. When I do the editing and finalize it, I choose pretty high settings hoping to have minimum loss of quality. The end result is a HUGE file, much much bigger than the original (still with some loss of quality). On top of that, if I upload that big file to Youtube, I guess Youtube compresses it like there's no tomorrow and the resulting quality is bad.

 

edited files should be done lossless at first until you're satisfied with the result and then (if any) apply compression,

 

I guess that part I'm doing right, I only apply compression once at the end. Is there a way to simply cut the original file and re-save it, without compressing it?

[PeaceSells]

try using x264 format for encoding the output edited file

eg I take a 4G fraps recording and encode it using x264 now it is 300MB quality is damn good

 

I will try that. Need to reinstall the video editor to start experimenting again.

[hansangb]

Also, don't forget that you're recorded aspect ratio needs to be preserved when you create the final video. If it's 1.7778 (1920x1080), make sure the output isn't a different aspect ratio.