1

Suppose a high quality, uncompressed video is re-encoded twice, with almost identical encoding settings at a relatively low bitrate of 4mbps, but at different resolutions, first at 1080p, and then at 720p.

So we now have two videos: One is 1080p and the other one is 720p. Both have identical bitrates.

I know that 4mbps is considered a low bitrate for 1080p, and the video will look bad on a full-HD display due to the compression artifacts.

However, during playback on a 720p display, the 1080p video will obviously be downscaled to 720p.

My question is: On the 720p display, will the 1080p video (which is being downscaled to 720p in real time during playback) look as good as the 720p video (which has the same bitrate)? Or will the 720p video (which was downscaled from 1080p to 720p by the encoder) look better? Or will both of them look the same?

I would run some tests to see this for myself, but my system isn't powerful enough for 1080p encoding. I'm looking for some expert views on this.

3
  • 1
    Compression artefacts would depend to some extent on the particular encoder used, but I would imagine that no, the downscaled artefacted video will not look as good as one natively encoded for the lower target resolution, given the same video data bitrate in both cases, because the 1080p video will suffer from artefacts. However, if you scale up the bitrate for the higher resolution video to match its increased data rate needs, then I'd expect them to look approximately the same on a 720p display. Unfortunately, I don't really have any actual facts with which to back up this opinion.
    – user
    May 17, 2014 at 10:52
  • @Michael Kjörling Yes, but I was also wondering, wouldn't the artefacts in the 1080p video be less visible after being downscaled to 720p? May 17, 2014 at 10:59
  • 1
    That would depend on the specific type of artefacts, but I doubt blockiness (MPEG style) would improve much when downscaling unless you downscale by a rather extreme amount.
    – user
    May 17, 2014 at 11:42

1 Answer 1

-1

When I stream at 720p have my game running at 3820x2160 and the playback is definetly noticeably better on the playback than if I was playing the game a 1920x1080p while streaming 720p.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .