Is Tsmuxer to AVCHD format changing the AR of my encodes

[lchiu7]

Still question involves a number of potential components but I will start with tsmuxer since it seems be common.

I am some movies (source HD-DVD though that's not so relevant) to H.264 and finally to AVCHD format so I can play them on my Oppo BDP-80.

Some of the movies are 2.25:1 so I thought I could save encoding time and space by cropping out the back bits with the following statement in avisynth

crop(0,140,0,-140)

In the Megui preview it looks fine and the encode is also fine. If I play the output .264 file in any player, the AR looks fine. If I then encode the file to .ts or .m2ts muxing back the original audio, again the file looks fine.

But as soon as I put the file into AVCHD format, using either tsmuxer or multiAVCHD the file changes its AR to 16:9. When played back images look vertically stretched and nothing I can do with my projector can fix this AR. As an aside, multiAVCHD complains during processing that the AR of 1920:800 is non standard and will cause potential distortion of the image, which it does.

Given a .t2 file looks fine, how does the AVCHD format change the AR? Should I also be inserting an avisynth line to correct the AR after the truncate such as
LanczosResize(1920,1080)

Thanks for any assistance

Larry

[Inspector.Gadget]

Don't crop. You can of course crop, then edit, then add borders again - but the key thing is that to be valid your output frame size must be spec-compliant. A blind resize will produce exactly the same distortion problem you currently see. You need black borders if you don't have the full frame of content.

[lchiu7]

Thanks for that. I was cropping because I thought it would save time and space not encoding the black frames but hadn't realised the implications of that. Interestingly some of the content I encounter on the Internet has strange AR's like 1280:528 which looks like a 720P encode from a cropped 2.25:1 original source but play okay (well on a PC and on the Popcorn Hour). Is there anything to be lost/gained by cropping and then resizing as I noted in my original post or should I just forget it and encode as 1920x1080 for most of my content?

[deank]

You gain almost nothing and you lose all compatibility with BDMV and AVCHD.