Sharpening image before upscaling and downscaling

[luquinhas0021]

Can sharpening image, before upscaling or downscaling, decrease the lost of sharpness and the lost of details in result image, comparing with initial image?

[wonkey_monkey]

Why don't you just try it? You could have had your answer in the time it took you to write the above.

[hello_hello]

How is it being upscaled on playback? If it's a hardware player, you mightn't have any say about it.

I quite often downscale 1080p to 720p. If the 1080p source has 1080p worth of detail, which it often doesn't, you'll lose a little when downscaling. That aside though, I usually open the resized script (Spline36Resize for downscaling) with MPC-HC, open the source with a second instance of MPC-HC and compare them running full screen before encoding. If MPC-HC is upscaling with the bilinear resizer, there's invariably a small loss of sharpness at after upscaling to 1080p again, compared to the source (which is already 1080p and not being resized). If I switch to the Bicubic resizer, which is sharper, the 720p version usually looks at least as sharp as the source. It wouldn't be uncommon for it to look a little sharper though, and often I fiddle enough for the 720p version to be an improvement on the 1080p source.

If I add additional sharpening, I only ever sharpen with LSFMod, because I dislike video that looks sharpened. LSFMod's sharpening looks fairly natural if you don't overdo it. It's default sharpness is 100. I rarely go that high though. Mostly I reduce it to 75 or even 50. Especially if there's still some noise in the video. Not sharpening anything would have to be better than sharpening noise every time, at least to me.

If downscaling robs you of fine picture detail, sharpening won't bring it back. Often you can downscale without a visible loss of detail. Sometimes you lose picture detail in a scene here or there, but the majority of the time you don't. Sometimes a 1080p video is filled to the brim with 1808p worth of detail and you'll lose it when downscaling. Having said all that, I pause individual frames on my TV and switch between them to compare. I couldn't reliably pick 720p worth of detail from 1080p worth of detail when the pictures are moving, and back at normal viewing distance, so in that respect, maybe it doesn't matter too much anyway.

He's some links to a few screenshot comparisons I've posted before.

If you use Avisynth, and if you use MPC-HC and if you have a large monitor or have your PC connected to a TV, it's easy enough to create a script that downscales and upscales again, and changing the resizers in the script lets you compare them without having to encode anything.

Because the 1080p quality wasn't all that spectacular, 720p ended up looking better to me. Unless you like noisy video. Some people do, but I don't so I removed some of it.
1080p http://forum.videohelp.com/attachment.php?attachmentid=32837&d=1437984916
720p at 1080p. Upscaled by MPC-HC on playback.

Here's some screenshots of a frame at 1080p resized with Avisynth down to 720p and back and another resized down to 540p and back. Nothing was re-encoded and there was no additional sharpening, it was just to see what was lost though resizing.
http://forum.videohelp.com/threads/369485-960x540-HD?p=2367728&viewfull=1#post2367728

When I re-encode PAL 16:9 DVDs I generally resize them to 1024x576 or 960x540. The resizing sharpen a little so when it upscaled to 1080p on playback the encode generally looks a little sharper than source without applying dedicated sharpening. The purpose of these screenshots was to show someone the effect of resizing and upscaling. The DVD in question had already been over-sharpening when it was produced, so sharp resizing when encoding followed by sharp upscaling was definitely too sharp for me. Check Richard's hair in the forth pic.
http://forum.videohelp.com/threads/378501-Resolution-Bitrate-and-Quality?p=2444902&viewfull=1#post2444902

Full disclosure. You invariably lose something when you downscale, but if bionic eyes are a requirement to see it under normal condition, I can live with it.
1080p http://forum.videohelp.com/attachment.php?attachmentid=33060&d=1439099202
Downscaled to 720p for encoding http://forum.videohelp.com/attachment.php?attachmentid=33061&d=1439099433
Zooming in for a closer look.
1080p http://forum.videohelp.com/attachment.php?attachmentid=33165&d=1439577088
720p http://forum.videohelp.com/attachment.php?attachmentid=33166&d=1439577125

On the other hand, not having bionic eyes means now and then you can get away with a trip all the way down to 540p and back.
1080p http://forum.videohelp.com/attachment.php?attachmentid=32489&d=1436454311
540p http://forum.videohelp.com/attachment.php?attachmentid=32490&d=1436454479

I'd forgotten this. I was bored one day so I tried to make Twin Peaks less painful to watch to see if I could sit through it all. It didn't help. It still bored me silly so I didn't hang in long enough to find out who killed Laura Palmer (I think that was here name). I don't get Twin Peaks.
http://forum.videohelp.com/attachment.php?attachmentid=31337&d=1429521227
http://forum.videohelp.com/attachment.php?attachmentid=31338&d=1429521252

I think these screenshots were posted during yet another argument with an idiot who claimed encodes will never look as good as the source. I don't upload screenshots much anymore. People who claim 1080p always looks better than 720p are idiots. They prove it almost every time because if you offer evidence to the contrary, they invariably pretend they didn't see it and continue claiming 1080p always looks better.

576p http://forum.videohelp.com/attachment.php?attachmentid=30871&d=1427391802
540p http://forum.videohelp.com/attachment.php?attachmentid=30872&d=1427391921

Of all those comparison screenshots, only two were encoded and they were the only two to have a bit of additional sharpening applied. The first 720p comparison and the last 540p screenshot. It would have been LSFMod, after using QTGMC in progressive mode for noise removal. I guess that's why I don't sharpen HD very often. I do tend to sharpen most SD a little though.

[feisty2]

If I add additional sharpening, I only ever sharpen with LSFMod, because I dislike video that looks sharpened. LSFMod's sharpening looks fairly natural if you don't overdo it. It's default sharpness is 100. I rarely go that high though. Mostly I reduce it to 75 or even 50. Especially if there's still some noise in the video. Not sharpening anything would have to be better than sharpening noise every time, at least to me.


seriously??
I'm not trying to pick up a fight but lsfmod is one of my least favorite filters.. and the reason I don't like it is that it looks super unnatural and "sharpened"..
and I'm not advertising my sharpening filter, see comparisons here: https://forum.doom9.org/showthread.php?t=173775
and I assume you won't use my filter anyways since you guys don't use vaporsynth, but in the avisynth world, finesharp looks much more natural and much less "sharpened"
which makes me wonder how you define "look natural"