Anamorphic encoding?

[Lester Burnham]

I've used AutoGK for many years for converting my DVDs to AVI to use on media players.

I've recently bought a (hard drive based) media player I use that connects via HDMI to a TV - and compared with previous media players (say connected by SCART, or other means) HDMI appears to always make the TV believe it should be displaying a widescreen image.

And by playing around with the various aspect ratio settings on the TV, don't seem to be able to get (mainly) widescreen AVIs I've previously converted, to display correctly.

So I was wondering about re-encoding / converting my AVIs from source (DVD) and leaving the video with the anamorphic extra lines still present (where the source is anamorphic), still cropping any black borders whilst converting.

Are there any conversion GUIs, here, that support anamorphic encoding - I much prefer the all-in-one type GUIs like AutoGK - and if so, what settings should be used to make them produce anamorphic AVIs as output?

[yetanotherid]

In what way don't they display correctly?

To help answer the question....
What other formats does the media player support? You'd probably want to be converting using the x264 encoder instead of XviD, and the MKV container (or maybe MP4) instead of AVI.

After I switched from AutoGK I tried most of the usual suspects and settled on MeGUI. It can be a bit more work to set up an encode than AutoGK (and a bit more of a learning curve) but it's a good program once you get to know it. You'll find a couple of guides for it via Google but I just worked it out by playing around and asking a few questions here. Basically you just select one of the anamorphic encoding options if you want to encode that way and still crop as usual.


So I was wondering about re-encoding / converting my AVIs from source (DVD) and leaving the video with the anamorphic extra lines still present (where the source is anamorphic), still cropping any black borders whilst converting.

I'm not sure what you mean there. Anamorphic encoding basically refers to encoding with non-square pixels. When encoding DVDs you generally set out to use the same pixel aspect ratio as the original DVD, which don't use square pixels (as opposed to AVI encoding where the video is generally resized down to use square pixels).
There's no extra lines as such so it's really up to the player/TV to display the video at the correct aspect ratio if you crop the black bars. It shouldn't matter too much what the shape of the pixels are, unless the player is making an incorrect assumption about the shape of the pixels used in the AVI for some reason, causing it to display the video incorrectly.

I'm kind of wondering if it'll solve your problem but I don't know anything about your player or TV. One thing I'd try first, assuming your player supports MKV files.....
Install MKVToolNix and use MKVMergeGUI to open an AVI which doesn't display correctly. Don't touch anything, just resave it as an MKV file (you're not converting anything, just re-muxing the AVI as an MKV file). Try playing that MKV file. If it still doesn't display correctly then anamorphic encoding on it's own mightn't solve the problem.

[Ghitulescu]

I've used AutoGK for many years for converting my DVDs to AVI to use on media players.

I've recently bought a (hard drive based) media player I use that connects via HDMI to a TV - and compared with previous media players (say connected by SCART, or other means) HDMI appears to always make the TV believe it should be displaying a widescreen image.

And by playing around with the various aspect ratio settings on the TV, don't seem to be able to get (mainly) widescreen AVIs I've previously converted, to display correctly.

So you have found finally that converting DVDs to AVIs is somehow wrong (at least, not universal). Yet you insist on reencoding the DVDs on AVIs, again. And I suppose you'll do it again when you'll buy the next media player.

There are several issues that have to be taken care of (your side) and some testing needed (player side):

PAR (PC is 1, TV is <> 1) - some standalone players obey the correct PAR
Colour (PC 0-255, TV 16-237) - some players take this into account
frame size - a player must convert any video to PAL/NTSC size. Only the developer knows how 624x248 is fit into 720x576 (it's very cumbersome to determine this)
DAR - this seems to be no problem, unless incorrectly set into the AVI

I would keep the DVDs as DVDs, but it's your time and your viewing pleasure in the end ...
You may try however the MKV/H.264 combination if you still use the HDD of 6.4GB of the gold era of AVIs and not the modern ones ....

[yetanotherid]

Hopefully the OP will give himself a serious smack on the bottom. ;)

I've never, ever seen a media player which couldn't display an AVI correctly on a standard TV. Maybe I've lived a sheltered life, but if displaying an AVI correctly isn't about at universal as it gets, I don't know what is.

Personally I think he's maybe missing a setting in the player, or getting something else wrong without realising it, or maybe the player has issues and could use a firmware update, or maybe it's just a crappy player..... as I said I'm not sure anamorphic encoding will solve the problem, it might be something else, but to try to scare the OP into thinking he's going to have to re-convert his DVDs into new AVIs every time he buys a new media player is nothing short of ridiculous.

PAR (PC is 1, TV is <> 1)

I thought modern TVs used square pixels too?

frame size - a player must convert any video to PAL/NTSC size. Only the developer knows how 624x248 is fit into 720x576 (it's very cumbersome to determine this)

What sort of TV/player are you referring to? I'd be guessing the OP has moved out of analogue land. Where does 720x576 come into it when using a square pixel AVI and a 720p or 1080p TV?
I've never, ever seen a resized AVI display incorrectly on an analogue TV either (at least not noticeably), not if the player/TV aspect ratio is setup correctly. Have you?

[Lester Burnham]

Whoa, whoa, whoa - I'm not talking about recoding to suit every media player I buy. What I am saying is that HDMI spec is that everything is (largely) considered to be widescreen (and I suspect most TVs interpret that as anamorphic widescreen).

So what I'm saying is that the TV that I normally use, connected to this media player, using HDMI, displays any widescreen AVIs in what appears to be slightly incorrect aspect ratio.

I've tried using every aspect ratio selection on the TV (plus all the settings on the media player) but everything looks slightly wrong. I've also tried connecting the player to a different TV using HDMI, which seemingly has even less aspect ratio selections when connected in this way (it's a fairly recent Sony LCD TV) and again nothing looks correct - on this TV it's perhaps worse than the normal TV I use with this media player - as the Sony TV does not allow a 4:3 aspect ratio setting, with this source connected using HDMI.

From what I gather in terms of HDMI as a transport, there's no aspect ratio signalling - as everything is assumed to be widescreen. I gather that displaying video sent, is the responsibility of the source device.

Now for other media players I have that connect over SCART (so effectively SD) AVIs are displayed correctly. The media player sends widescreen signalling over the appropriate SCART pin (8 or 9, or whatever it is) the TV correctly switches to wide, and the media player sends / constructs the video to the TV such that things are displayed correctly (so even if the source AVI may be 4:3, and the TV in widescreen mode, the media player must be sufficiently savvy, to make the image aspect ratio correct).

This is the first device I've used connected over HDMI, though, so first wondered whether the device was correctly sending aspect ratio information over HDMI - which was a bogus consideration for me, because only after research did I find no such thing happens over HDMI.

So it could well be that this new media player is a bit crappy in terms of how it frames various source aspect ratios on the type of display it's configured with, and on some players, maybe this would be fixed by firmware. But as of yet, there are no firmware updates. And I'd still like to use it.

I do have lots of AVIs on it - mostly films, but some TV. Vast majority, I'd say widescreen, but some 4:3 material. All of it, I have source for, though, because it was created by converting to AVI from DVD.

Now I have read comments, on here, about people using autogk, forcing 4:3 output, and using mpeg4modifier to modify either the DAR or PAR in the AVIs.

I guess my main enquiry was about all-in-ones and if they could be configured so, because I'll probably still convert DVDs to AVI in the future.

As to using the mkv container, from memory, I'm fairly sure this particular media player doesn't support it. And as to using it, it may sound crappy, but it's for my bedroom, as a replacement to an older one that was playing up - and in my defence, it was cheap, and has quite a bit of capacity compared to what it replace (1TB compared with 160GB).

[7ekno]

With AVI playback devices the only true "universal" correct AR method is square pixel, hence it's universal use for "scene releases" ;)

AVI playback devices (and some PC media players!) often ignore the Aspect Ratio flags of "anamorphic" encodes, resulting in unusual display of such files ....

Solutions:
- buy a media player you know honours the AVI container AR flag (difficult to assess without trying the player, manufacturers don't state this ability)
- convert to "square pixel" AVI files for wider compatibility
- redesign your system around a file type that has AR flag enforced by all players (MKV, to a lesser extent MP4)

7ek

[Ghitulescu]

I've never, ever seen a media player which couldn't display an AVI correctly on a standard TV. Maybe I've lived a sheltered life, but if displaying an AVI correctly isn't about at universal as it gets, I don't know what is.
I did, I borrowed once such a player from a friend to see if it's worth buying one. On both TVs, 4:3 and 16:9, there were distorsions due to PAR.
I thought modern TVs used square pixels too?
Indeed, but the signal still has to obey PAL/NTSC requirements (on the wire) until it reaches the quadratic pixel screen. That's the problem, which is often ignorated, as few people notice it, and there are bigger ones (like DAR).
What sort of TV/player are you referring to? I'd be guessing the OP has moved out of analogue land. Where does 720x576 come into it when using a square pixel AVI and a 720p or 1080p TV?
Both SCART/CHINCH and HDMI have to use standard resolutions (PAL/NTSC and HD formats). There's no way of sending, even digitally, a 16:9 AVI movie of 852x480 or 640x234 (I think these are the most used resolutions), they have to be converted.

I hope this is clear now.