NON-square pixel rendering

[tommytucker]

Can't find an answer in the search for topic or manual...but should this checkbox be checked or unchecked? I am using VS12+ and burning DVDs for playback on a Plasma TV. Thanks.

[sjj1805]

Non Square Pixel Rendering.

I admit that this used to confuse me for quite a while until eventually the penny dropped - so let me explain it in laymans language.

Think of a screen size - any screen size will do, for arguments sake we will say that our screen size is 100 x 100.
If we use Square pixels then we will have a perfect 100 x 100 square like a sheet of graph paper.
If we use non square pixels then these pixels could be oblong in shape.
Therefore the 100 x 100 will not be square.

To clarify that even further lets put some sizes to those pixels.
Let us say that our square pixels are 1" x 1" (OK a pixel isn't an inch - I am just trying to make things clear)
so we have a 100 x 100 square measuring 100" x 100"

In our non square pixel example each pixel is 1" high x 2" wide
so now our 100 x 100 grid is in fact 100" x 200" (Oblong)

Both examples contain a 100 x 100 grid but in the square one it is "Square" - the non-square one is "Oblong".

[Trevor Andrew]

Hi Tommy

I believe Non Square Pixel Rendering is selected by default.

One reason for deselecting is if you have a problem video file, where the video displays as squashed or distorted.
Under normal circumstances leave it selected.

Unlike Still images (Jpeg¡¦s etc) video pixels are rectangular not square. They are stretched rectangular by using ¡¥non square pixel rendering¡¦.

Widescreen (16:9) video is usually associated with non square pixel rendering although 4:3 is still affected.

For Pal 4:3------- (720 x 576) is not 4 x 3 (pixels are stretched to a 4:3 aspect
If we used square pixels we would need 768 x 576

For 16:9 widescreen --------(720 x 576) is still used but again stretched to 16:9.
If we were to use square pixels we would need 1024 x 576.

High Definition
Afaik ----- HD acts in a similar manner using nonsquare pixel rendering, unless you are using full screen size of 1920 x 1080, which is 16 x 9

[Devil]

Sorry, Trevor, but 704 or 720-wide imaging is always really 768, which is why DV always has two narrow black bands on either side, in the overscan area. For PAL, the pixels are square, but for NTSC they aren't, because 768x480 h is 8:5 for a 4:3 image.

For SD 16:9, the same applies, because the recorded pixels are still 768x576 or 480. The fact that they are letterboxed or anamorphic changes nothing.

[Trevor Andrew]

Hi Devil

My DV video from Panasonic GS400 never shows any black borders.
I see a full screen video. I normally shoot in 16:9

You should not see any black borders on your video frame, only video.

When using widescreen the preview screen will show black sections, these are the unused areas of the preview screen. Change the background colour for VS in preferences , this will allow you to view the actual video frame.

Make sure Nonsquare pixel rendering is selected, otherwise your video will display as square pixels, and show a border.

As a further test take a screen shot using Clip-Save as still image, then take it again in Project Playback using Tools-Save current frame as image, this will take what you see on screen. If you see black borders then you have a problem.

[tommytucker]

so the non square is checked by default..and I should leave it checked..thanks!