Need help with aspect ratio of MKV / M2TS file

[FulciLives]

Hello

I'm having an aspect ratio issue with this one file that I recently converted and I'm not sure how to fix it. Allow me to explain:

I ripped a PAL format DVD that is 16x9 anamorphic but with a real aspect ratio of 2.35:1 and I wanted to convert it to h.264 video with AC-3 audio (straight from the DVD) into a MKV file. In the conversion I cropped the video from 720x576 to 720x432 and while I do NOT think this has any bearing I also slowed it down from 25fps to 23.976fps using the AviSynth AssumeFPS option (yes I also slowed down the audio to match).

So I got a MKV that has h.264 video with a resolution of 720x432 at 23.976fps with AC-3 audio. The 720x432 is still 16x9 anamorphic so it should play back at 1024x432 (if I had not cropped it then it would play back at 1024x576).

Now in mkvmerge I can set it to 1024x432 or I can set the aspect ratio to 2:35:1 and either way it does play back properly.

However I often use a PS3 for playback and so I convert my MKV files to M2TS files using tsMuxeR and when I convert this MKV (regardless of which way I set the ratio as described above) the resulting M2TS plays back in the wrong ratio. The M2TS file tells me the ratio is 1.66:1 which as it turns out is this:

720 / 432 = 1.66:1

I can't seem to get the M2TS to understand that this is a 16x9 video cropped to 2.35:1 aspect ratio.

Thoughts?

- John "FulciLives" Coleman

P.S.
I'm tempted to redo this and leave it at 720x576 instead of cropping it and then if I tell it that it is 16x9 it should work but I don't see why I can't have it work with the cropped video but alas I don't know how to make it work (hence my thread here).

[davexnet]

The ps3 is not honoring the file aspect ratio flags? I don't own one, so I don't know if it's able to do so or not.
Have you ever got it to honor the flag?

[intracube]

So I got a MKV that has h.264 video with a resolution of 720x432 at 23.976fps with AC-3 audio. The 720x432 is still 16x9 anamorphic so it should play back at 1024x432

What you mean is the pixel aspect ratio is the same as the original 720x576 source. Cropping the frame will change the display AR to roughly 2.37:1

when I convert this MKV (regardless of which way I set the ratio as described above) the resulting M2TS plays back in the wrong ratio.

It looks like the m2ts/BDAV spec only allows video streams to have 4:3 and 16:9 display aspect ratios (page 17):
http://www.blu-raydisc.com/Assets/Downloadablefile/2b_bdrom_audiovisualapplication_030...2955-15269.pdf

If this is true, leaving the video as 720x576 is the only thing to do.

[FulciLives]

It seems the only options to make it work as both a MKV and a M2TS file is to:

1.) Leave it at 720x576 (in other words no cropping) and set it to 16x9 (it will then resize properly as a MKV and as a M2TS)
2.) Crop the black (which makes it 720x432) and then resize to 1024x432 which is basically taking the 16x9 image and making it a square pixel image. In other words 720x576 that is 16x9 gets stretched out to 1024x576 on playback. So since I'm cropping the black it would resize to 1024x432

If I do what I did originally (crop to 720x432 without resizing) then it will work as a MKV but not as a M2TS because apparently the M2TS will see it as 1.66:1 since 720/432 is 1.66:1 and there seems to be no way to tell the M2TS file to resize it in another way.

Such a pain-in-the-ass this is *sigh*

- John "FulciLives" Coleman

[intracube]

It seems the only options to make it work as both a MKV and a M2TS file is to:

1.) Leave it at 720x576 (in other words no cropping) and set it to 16x9 (it will then resize properly as a MKV and as a M2TS)
2.) Crop the black (which makes it 720x432) and then resize to 1024x432 which is basically taking the 16x9 image and making it a square pixel image. In other words 720x576 that is 16x9 gets stretched out to 1024x576 on playback. So since I'm cropping the black it would resize to 1024x432

Whether 2. works or not depends on how closely the PS3 follows the m2ts/BDAV spec - 1024x432 isn't listed in the pdf. Unless the PS3 upscales badly, I can't see any reason for doing this.

Does the PS3 play the 23.976fps 720x576 m2ts ok? This framerate/res combination doesn't appear to be officially supported.

I'd go with option 1 with a minor change; when converting from DVD, crop to 720x432 then pad straight back to 720x576. This will regenerate the black bars and make sure they are completely uniform and free from any noise. h264/x264 will then compress the area very efficiently.

[FulciLives]

The PS3 will properly play back a 720x576 16x9 video in a M2TS file. When "not cropping" I always crop the black and add back. Learned that trick a long time ago heh

I really need to get a hardware media device that can just play MKV files *sigh*

- John "FulciLives" Coleman

[intracube]

When "not cropping" I always crop the black and add back. Learned that trick a long time ago heh

I really need to get a hardware media device that can just play MKV files *sigh*

*cough* WDTV Live

haven't got one myself, but they get a lot of positive comments on the forums

[jagabo]

Doesn't the PS3 play MP4 files? Will it respect AR flags there?

[FulciLives]

I don't have much experience playing MP4 on the PS3 because you have to convert the audio to AAC so yes it will do it but I never do that myself. Instead I use M2TS which allows AC-3 audio. Normally I don't have aspect ratio issues with M2TS but normally I'm playing back 1080p or 720p files that are 1:1 pixel ratio so even if cropped they play back properly. The problem with this file is that is not 1:1 pixel ratio and cropped and apparently M2TS can't deal with that situation.

I don't know if it will play it properly as a MP4 but I'm not really interested in that. I made a version that I'm happy with that is 720x432 (cropped) and it works fine as a MKV on a computer. I'll keep that but I might go ahead now and do a 2nd version just for my PS3 (where I'll do all the same stuff but not crop it).

This is an important project for me and I'd rather it be "proper" and be cropped than not be cropped just so I can play it on my PS3 when we all know that eventually I'll probably get some sort of solution that will allow MKV playback on my TV. In fact I'm looking at Blu-Ray players that can play MKV via a DVD "data" disc and USB 2.0

So yeah I'm going to keep the cropped one but also make another one that is not cropped so I can watch it on my PS3 until I can view the other file. I know if I delete the cropped one and keep the uncropped one that I'll regret it later on down the road. Best to just have both versions for now.

Still this was a learning experience. I had no idea that the cropping would screw up the M2TS since I play cropped HD video all the time. I just wasn't expecting the 16x9 anamorphic cropped video issue. Now I know.

It really is frustrating that the PS3 doesn't support MKV. It surely can if Sony wanted it to. I mean hell the thing can handle M2TS files that are 1080p with insanely high bitrates that even make my quad core CPU choke at times on playback (although I admit my quad core is an old model now and my video card is 1080p approved but obviously barely acceptable at times).

Anyway thanks all for the help

- John "FulciLives" Coleman

[jagabo]

I don't have much experience playing MP4 on the PS3 because you have to convert the audio to AAC so yes it will do it but I never do that myself.

MP4 has officially supported AC3 audio for the last few years. I don't know if the PS3 supports AC3 in MP4 though.

Instead I use M2TS which allows AC-3 audio. Normally I don't have aspect ratio issues with M2TS but normally I'm playing back 1080p or 720p files that are 1:1 pixel ratio so even if cropped they play back properly. The problem with this file is that is not 1:1 pixel ratio and cropped and apparently M2TS can't deal with that situation.

I don't know about the M2TS container, but MPEG 2 encoding supports only four aspect ratio settings: 1:1 PAR (square pixel), 4:3, 16:9, and 2.21:1 DAR. So if you want to properly display 2:4:1 movies you have to retain the black borders and use 16:9 DAR, or crop the borders, resize to square pixel, and use square pixel encoding.

For DVD rips I crop black borders and encode with x264 with the original PAR (SAR in x264 parlance) and mux the video and original AC3 audio in an MKV. I just make sure that all my players (Blu-ray, WDTV, etc.) support MKV and the aspect ratio settings. I don't care about the PS3 or Xbox 360.

[FulciLives]

I know the PS3 plays MP4 with AAC and also supports 5.1 AAC but I don't know about AC-3 in a MP4 file. I know the AppleTV does that and I think that is how the iTunes movies come (or so I've heard) but I've also heard that Apple putting AC-3 in MP4 is a "hack" and thus unofficial.

The PS3 is the only media player I have on the HDTV ... computer is too far for a direct connect (and not a laptop so not easy-to-move) and I'm too broke for new hardware.

I did mention I'm looking into MKV capable Blu-Ray players. Partly for a friend who wants one and partly because I'd like one but I'll probably have to wait myself until Christmas when I can sucker some family member into buying it for me.

I try to avoid SD material these days and stick to HD but of course there's some kewl shit on the 'net if you know where to look and a lot of it is SD because there is no HD version yet (damn me and my love of rare horror/cult/exploitation films).

- John "FulciLives" Coleman

P.S.
Some images of the project that gave me so much trouble and started this thread. The good news is the 25fps to 23.976fps conversion went well while still maintaining the PAL resolution. In the old days I would have had to convert to NTSC DVD and drop from 720x576 (or 1024x576 if anamorphic) to 720x480 (or 853x480 if anamorphic). Nice to have a proper frame rate change yet keep the added resolution.













Right Click (with mouse) on image and select "open image in new tab" to see the full resolution of 1024x432 (images made with VLC media player).

[jagabo]

I've also heard that Apple putting AC-3 in MP4 is a "hack" and thus unofficial.

You heard wrong. AC3 was added to the official spec a few years ago:
http://webapp.etsi.org/WorkProgram/Report_WorkItem.asp?WKI_ID=28541

[FulciLives]

I've also heard that Apple putting AC-3 in MP4 is a "hack" and thus unofficial.

You heard wrong. AC3 was added to the official spec a few years ago.

I believe you but other than files intended for the Apple TV ... I've never seen an MP4 with AC-3 audio on-line. I wouldn't even know how to do that or mux it.

But that sounds like info for another thread heh

- John "FulciLives" Coleman

[intracube]

Ah, The Devils (1971).

Some stills were posted on here a while back. I've been meaning to watch it.

The set design alone (I assume that's a large set) caught my interest.

Have you got the new BFI DVD?

[FulciLives]

Ah, The Devils (1971).

Some stills were posted on here a while back. I've been meaning to watch it.

The set design alone (I assume that's a large set) caught my interest.

Have you got the new BFI DVD?

Yes I have the BFI DVD. In fact the image grabs above are from it. Well not directly as they are from my re-encode. I re-encoded it so I could slow it down from 25fps to 23.976fps (also slowed down the audio) so I have a normal proper FILM rate for it.

I did the re-encode with x264 High@L4.0 and did a constant quality CRF of 15 which turned out perfect size wise because with the audio muxed in (640 AC-3 for the movie and 320 AC-3 for the commentary) I got it at 4.31GB so it fits a single layer perfectly. The idea was to max the quality of x264 so as to lose as little quality as possible while doing the conversion.

- John "FulciLives" Coleman