Tuesday, 31 January 2017

AH and GA play Burnout 3 without de-interlacing the video (not a rant)

I figured I'd talk about what's possible in modern video here. I was a bit short with one of the commenters in the original video page so I decided to try and explain everything without any venom (because I want to make sure people understand and learn, not feel stupid).

They went back to a slightly older game from the PS2/Xbox Original days known as Burnout 3 (obviously). It originally launched with tech that could barely render 480i without having severe frame rate issues. As you may or may not know, 480i means the video is interlaced. Half of the field from one frame is mixed with half of the field from the next frame. What determines a field is every odd number line is the top and the even number lines are the bottom. The reason why that happens is because of a holdover from technology that we no longer use. We can fix the image so it looks better, very easily in fact. It becomes harder to fix the further in the production process you are, though. I took some time to see if de-interlacing could be done with my setup and it worked out as well as could be expected. Here's a breakdown of the topic:

TV and cameras used to do interlacing when mass video consumption was developing since it was the most efficient way to send a video signal over-the-air through large antennae to each person's home antenna and TV. The camera would scan odd lines first, then go back over the same image and scan the bottom lines and send them in that order. In one frame, it would then create an image with the top field and wait for the bottom field, then the bottom field would show up and it would display both at the same time as the second frame. Sounds like it should be a progressive image, but it won't be for long. The next frame is then the old bottom field with the information from the next top field. This is frame 3. Then the top field from the last frame is held in place while the new bottom field is combined with it and is displayed as frame 4. Thus resulting in interlaced video being very awkward in modern day technology.

Moving on to progressive video, we now do every line as part of a whole with the entire image being displayed at once. It's always been possible to change interlaced into progressive, however you end up with a slower frame rate. You take half of the fields from one frame and half from the next to create a whole frame. Since both fields are technically on 2 frames, you then cut out half of them or simply leave it as doubled up frames in a 60FPS NTFS [50FPS PAL] video format (seems wasteful, but it doesn't really make much of a difference). This would change it from 480i to 480p. Sounds simple, and it is. There's just one catch;

While it's possible to de-interlace a video, you must know what resolution it was originally, or the field order becomes unusable. Technology today uses 720p by default for the low end and 1080p as the new standard (I know, 4k is coming around but until it's in budget phones, 1080p is the "new standard"), however games 12.5 years ago were only 480i. In this Let's Play scenario, de-interlacing an upscaled recording technically would make things worse. Every other line from 720 would not match up since it's no longer every other line from 480. However, downscaling and then de-iinterlacing can yield some decent results. It just depends on how much compression was used and if the frame rate is perfectly stable.

Now for the last part; I downloaded the video (I'm a first member, I do pay for the content so I'm not quite stealing >.>') and used a standard de-interlace filter in my video decoder while playing it. This is the result (top images are the original, bottom images are the de-interlaced versions):

http://imgur.com/a/JLXiV

It looks alright and the banding isn't nearly as noticeable, but the game hasn't aged well. Some people said that it was "extremely difficult" and made some sort of claim about it not being possible (so I went on a rant in the comments, hence the venom I mentioned earlier), which then made me realize that people aren't as educated as they should be on this particular subject. I wanted to inform people about why the video looks the way it does, what could've been done about it, and to show that it's entirely possible to fix using very basic tools. I have been studying and using video for half of my life now and I'm almost 30. I had classes in high school on video production, took several college courses as well, learned the ins and outs of various codecs, kept up with compression techniques, and overall have been utilizing what I know to do side projects of my own (I don't upload them anywhere, it's just for my personal collection).

In short, what happened with the interlacing could've been avoided if Achievement Hunter or Game Attack had used a different setting somewhere or changed the encoding format prior to editing, but once it was done and uploaded, there isn't much that could fix it. Hopefully people are understanding after reading this and will look past the video quality to see the content for the entertainment value that it is. And for those who think that it can't be fixed, at least know there is a way, even if it's a slightly longer process. Thanks for reading and have fun watching the content.

(Sorry if this is posted multiple times, it seemed like it didn't work when I first submitted it so I waited a moment and pressed the button a couple extra times)



Submitted by NaRu7o | #Specialdealer Special Offer Online Shopping Store 2016

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