How to stop Sony AVC/MVC encoder from adding 4:3 aspect ratio to 16:9 videos?

Question

I am using Movie Studio Platinum 13 (essentially, light version of Sony Vegas).

I am creating a project based on mp4 files recorded on my Sony Alpha camera. These files have pixel resolution 1440x1080 and aspect ratio 16:9, which means that they are anamorphic (pixel aspect 1.333) and are stretched to 1920x1080 when playing back. All the video players I tried are playing the files with correct aspect ratio. Mediainfo tool shows the following information:

When creating the project, I specify that I want to detect project settings from an existing file and I pick the file from the camera.

When rendering the movie, I pick Sony AVC/MVC encoder and specify the settings as in the original videos (1440x1080@30p, 1.333 pixel ratio for anamorphic aspect ratio, 25 FPS):

But the final rendered movie plays back with black bars and 4:3 aspect ratio on some video players! When I inspect the media information, I see the following:

The Sony AVC/MVC encoder has added "Original display aspect ratio" as 16:9 and set "Display aspect ratio" to 4:3, whereas in the source files "Display aspect ratio" was 16:9 and there was no "Original display aspect ratio" at all.

Why is Sony encoder doing this? How do I force it not to add 4:3 ratio but keep them all at 16:9 while using the same anamorphic pixel ratio for 1440 -> 1920 stretching?

Answer 1

In project properties, set your pixel aspect ratio to 1.333 as well. Furthermore, make sure that when you right-click a video on your timeline that both resample is disabled, and try fiddling around with the "maintain aspect ratio" option. I have a hunch that it has got to do with these settings.

Try using different formats/encoders as well to see what effect that gives.

Answer 2

I suppose some video players do not support non-square pixels, or can't read this flag from the file attributes. Why don't you use 1920x1080 format with square pixels? 1440*1.3333=1920 ;)