logo Sign In

Restoration tips: Slice Technique™



What's about this so-called Slice Technique™?

In few words: achieve the widest (highest) image possible adding a "slice" of another video clip.

Be more specific...

Well, sometimes there are two editions of the same movie, where one has more image on one side, while less on the other side, and vice versa. So I thought to use the missing "slice" of one joined together with all the other, to obtain the widest image possible. Indeed, it could be only (e.g.) 3% wider than any each version, but I much prefer a 100% wide image Vs a "mere" 97%... (^^,)

Of course, it's quite difficult - sometimes impossible - to use this technique with every movie, because what must be taken in account are the dimensions (eventual image rotation, width and heigth of sources and chosen slice, eventual resizing and cropping, exact point of matching), colors (both versions should have the same color grading, or one should color match the other), video quality (grain, resolution/definition, different compression used in the sources, frame whobbling in a version not present in the other - in particular at the beginning and ending of a shot), etc.

In these examples, I used a vertical slice and two sources, but it's possible to use an horizontal slice, or even multiple slices from various sources - obviously, in this case, a good result will be astonishingly difficult...

Hint: best results are from two versions with same resolution - like 2 Blu-rays, 2 DVDs, 1 Blu-ray and 1 HDTV.


"Escape from New York" examples (attention: only preliminary tests, not used for final project)

comparison clip between the BD and the [spoRv] version; 120MB, 1920x1080, AC3 5.1, 8000kbps

http://www.sendspace.com/file/haau7q (new link)

comparison screenshots:

Second test clip needed different settings for different shots; just four settings worked for the whole test, but to "slice" a whole movie, a lot of settings are needed.

It looks like there's more image at the bottom in some shots on the XXX Vs. YYY. It is possible to adjust that too?

It is not possible to use it, as the small "slice" on the bottom of the YYY is missing... like the following example:

see the missing piece at the bottom right? Unless there is some method to "invent" the missing piece using surrounding images... and I'm afraid, there is not (yet)!

How about using XXX as the main source and just adjusting the colors, instead of using the YYY?

It depends... if XXX color matched with YYY as color reference is better, then use XXX; if not, then use YYY - I must add that sometimes the best solution is to use XXX for some scenes and YYY for others... your mileage can vary!

Comments, improvements, corrections are welcome!

Sadly my projects are lost due to an HDD crash… 😦 | [Fundamental Collection] thread | blog.spoRv.com | fan preservation forum: fanres.com


_,,,^..^,,,_ said:

see the missing piece at the bottom right? Unless there is some method to "invent" the missing piece using surrounding images... and I'm afraid, there is not (yet)!

Photoshop has a function that replaces a section of an image with estimated data from the region around it.  I'm not sure if there is an open source implementation of this out there, but I believe you could get decent automated results in this case since you are operating in the very corner of every frame.

A similar technique could also be used to aid with logo removal, but more noticeable artifacts would probably occur when compared to the above example since the logo can intrude quite far into the frame.


That sounds like inpainting - there is an AviSynth plugin called AVSInpaint which I've used in the past with varying degrees of success.

Guidelines for post content and general behaviour: read announcement here

Max. allowable image sizes in signatures: reminder here