Another question: Converting square pixels into round pixels.

[Earthling2000]

"I tried to post this question earlier but my browser crashed while I was typing the question. And I accidentally pushed the submit button while trying to save my post. I apologize to the admin if that post was actually submitted."

Here is the question.

Hi,
I am not an expert at video work. I was just wondering about how to convert square video pixels into round pixels. I have tried many video encoders and a few video filter programs, but so far haven't found any software which produces round video pixels.
Here's an example
I want to change the pixels from this…



Into this…



I would also like to know if there is a way of removing the artifacts on compressed videos apart from applying the deinterlacing or deblocking filters. I have applied those filters as well as the resize filter to to my compressed videos in Virtualdub. But the square pixels still seem to be creating artifacts on the videos.

Please help.

[Baldrick]

I changed your post so it shows the images.

You can't do much with such bad video source...

[Earthling2000]

I know Baldrick. But that video is not really the source. And I sharpened that video a lot before taking the snapshot. So that the square pixels would become visible. It was only an example, so there is nothing to worry about. I would just like to know about how to convert the square pixels of a video into round pixels like those in the second picture. I would really appreciate your help.
Thanks in advance.

[jagabo]

That's not "round" pixels. It's a paint effect. Oil paint, pointillist, something like that. Many image editors and video editors have such filters.

[Gavino]

ROTFL.

With all this talk about 'square pixels' and 'non-square pixels', it was only a matter of time before someone asked for round pixels...

[poisondeathray]

Earthling2000 - The big square blocks in the 1st picture aren't pixels. Those are macroblocks from inadequate compression probably from a MPEG2 source. Each block is actually composed of 16x16 pixels.

In order to convert something like #1 into #2, you would need a better quality source. You could try deblocking filter first, then one of the effects jagabo mentioned, but it won't look very good unless you start with a decent quality source

[Earthling2000]

There is no paint effect in picture no. 2. I took that shot from a moving video that's why it looks like that. And I mentioned before that I'm not going to use the video in picture no.1 as source. I only wanted to use them both as an example and sharpened them before taking the screenshot in order to make those squares and circles appear. I'm also aware that in order to have a good encoding result one has to have a good source file. But what I'm asking about is something else.
I have used many dvd rippers and video encoders. And all of them seem to add or leave tiny square shaped dots(or pixels) on the end result video even if I use HD settings for encoding. And it appears like they construct the video bit by bit using those square shape dots. I read on another video forum that it has to do with the encoding method. And that one can either encode a video into square or circle shaped dots(or pixels). So what I understood was that DVD videos are encoded in round or circle dots. And if you sharpen a dvd video, those dots or pixels appear on the screen. With round dots the video appears much more clean and sharp and doesn't make a mess on the screen like those annoying square dots(I'm not talking about those blocks which poisondeathray mentioned). Here is an example.
This is a shot from a dvd


And this one is from the same movie scene but in VHS quality.



Notice those round dots in the dvd screen shot. I want to get that kind of effect by encoding. Dvd videos seem to be made of those tiny round dots. But I have also seen that effect in videos made by ordinary camcorders. I want to know how it's done.

I mentioned already that I'm not an expert at video work so please be very gentle. And If I'm describing something wrong, then please guide me.
Thanks in advance.

[poisondeathray]

Those "tiny dots" are usually referred to as grain. Most production studio's add it in post production before replication for a cinematic effect. Low light videos shot with video cameras that have poor sensitivity also exhibit grain

The problem is it acts as "noise" to the encoder, so you require much larger bitrates (filesizes) for similar or lower quality.

There are many filters, such as addgrain etc...many programs will have it. Avisynth has a few too. It's usually the job of pre-processsing filters, not the encoder to add the grain

If you use a low quality source, or low bitrates, it won't look very good.

[Earthling2000]

But I really want to get rid of those square shape dots. And if it's possible, then I want to convert them into round dots or make them extremely tiny. And I also want a good program for ripping or converting video formats. One that doesn't construct a video with square. Nor leaves any artifacts on the video. And doesn't make it blurry.
Thanks for the reply I highly appreciate it.

[poisondeathray]

The reason you are getting the macroblocking (square dot blocks like in the 1st screenshot), is because the compression you are using is not adequate. You can use deblocking filters, but it will make the video blurry.

You can't just convert them, because the source is too low quality. This was already discussed.

If you mean get rid of the grain, you can use denoising filters (e.g. if you mean convert the dvd screenshot to the vcd screenshot quality)

[manono]

Just to repeat, there are no round pixels. What you seem to be asking is how to add grain or noise to a video. That's easy enough to accomplish, depending on what you use. If using AviSynth there are a number of grain-adding filters, including GrainFactory3:

http://avisynth.org/mediawiki/GrainFactory3

Blockbuster:

http://kvcd.net/sansgrip/avisynth/Blockbuster-readme.html

and NoiseGenerator:

http://avisynth.org/warpenterprises/#noisegenerator

Edit: I was searching out the filters while you and pdr were discussing this. Yes, if the source is blocky, you can unblock it, but with the high price of losing detail. If you're creating the blocks yourself when reencoding, use a higher bitrate. One way to 'hide' the blocks is with added grain which also, as pdr mentioned, makes the video less compressible, but if you're trying to create the effect of that very nice 2nd picture you said you made yourself, adding grain is one way to do it.

[Earthling2000]

I'm talking about ripping dvd quality videos. I mostly use AutoGk and Format Factory and chose the same resolution and bitrate as the source. But after conversion the picture quality either becomes blurry or it picks up some sort of artifacts. If you could please suggest a better program for conversion which produces sharp and clean videos then I would be grateful.

[manono]

I'm talking about ripping dvd quality videos. I mostly use AutoGk and Format Factory and chose the same resolution and bitrate as the source. But after conversion the picture quality either becomes blurry or it picks up some sort of artifacts. If you could please suggest a better program for conversion which produces sharp and clean videos then I would be grateful.

If using AutoGK, post a log. I suspect you're setting a fixed width and aren't allowing AutoGK to create a decent video, and they're bitrate starved, hence the blocks. You won't get 'DVD quality videos' if compressing a full movie to CD size. AutoGK can produce decent quality videos if you allow enough file size, or allow it to find the correct resolution.

The filtering being discussed here is available only for manual encodes, and not an all-in-one app like AutoGK, as good as it is.

[Earthling2000]

Ok, I'll do that soon. Thank you so much. I really appreciate your help.