Correcting the aspect ratio for anamorphic video

General questions or discussion about HandBrake, Video and/or audio transcoding, trends etc.
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amiliv
Posts: 10
Joined: Sun Sep 09, 2007 5:36 am

Correcting the aspect ratio for anamorphic video

Post by amiliv »

Hi,

====================
Added February 21.

I've been told (later in this thread) that I made some false claims regarding HandBrake. It was not my intention. I simply wanted to ask couple of question. As it appears, I have poorly expressed myself.

For anybody reading this thread 6 months from now, HandBrake is storing correct information in the files it produces. There is no bug in HandBrake to be fixed. The files it produces have correct information on aspect ratio stored.

If you are using QuickTime or iTunes to play back anamorphic video, there's bug in that software (not HandBrake) that might distort the video. Almost any other player out there (for example VLC, mplayer) will play back files containing anamorphic video correctly. I was told that AppleTV will play back the files with anamorphic video correctly too. If you are using QuickTime or iTunes, do not bug hard working HandBrake developers. There is nothing they can do to fix Apple's software. There is nothing they could do to make QuickTime or iTunes play those files correctly. Report the problem directly to Apple instead. Tell them that QuickTime and iTunes are not playing back files with anamorphic video correctly. As an alternative, while you wait for Apple to fix QuickTime and iTunes, you can use VLC or mplayer to play back anamorphic video.

The remainder is original (unedited) version of my question.
====================

In "Picture Settings..." I've checked "Anamorphic (PAR)" option, and also cropped the image to get rid of black stripes at top/bottom, and than encoded the video using AppleTV presets. On playback (in both QuickTime and iTunes), the video now has wrong aspect ratio (it is stretched horizontally). Searching the forums I've found some discussion on this, and some suggestions on how to fix it in QuickTime. However, I must be missing something, since I can't find mentioned options in QuickTime menus/settings. Do I need QuickTime Pro to fix aspect ratio on those videos?

It would be very much appreciated if somebody could give me step by step instructions (and exact software I'd need) to fix the encoded files so that they are played back in correct aspect ratio.

Related question is, why didn't HandBrake store correct aspect ratio info in the output file? I know that DVD only has a flag telling if the video is 4:3 or 16:9, and for anything not fitting in those two, video must have black stripes/bars. Do the m4v files have the same restrictions? Or the HandBrake just copied 16:9 ratio info into the file, ignoring that the video was also cropped (which changed the aspect ratio of the output).

Thanks
Last edited by amiliv on Thu Feb 21, 2008 7:32 pm, edited 1 time in total.
jbrjake
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Re: Correcting the aspect ratio for anamorphic video

Post by jbrjake »

amiliv wrote:In "Picture Settings..." I've checked "Anamorphic (PAR)" option, and also cropped the image to get rid of black stripes at top/bottom, and than encoded the video using AppleTV presets. On playback (in both QuickTime and iTunes), the video now has wrong aspect ratio (it is stretched horizontally). Searching the forums I've found some discussion on this, and some suggestions on how to fix it in QuickTime. However, I must be missing something, since I can't find mentioned options in QuickTime menus/settings. Do I need QuickTime Pro to fix aspect ratio on those videos?
Yes, I believe video properties are only editable in Pro. But you're better off just not using QuickTime or iTunes to watch your videos. They should look fine on your AppleTV and they'll look fine in VLC, MPlayer, Etc.
It would be very much appreciated if somebody could give me step by step instructions (and exact software I'd need) to fix the encoded files so that they are played back in correct aspect ratio.
Um it's not fixing the files -- it's working around a QuickTime bug.
Related question is, why didn't HandBrake store correct aspect ratio info in the output file? I know that DVD only has a flag telling if the video is 4:3 or 16:9, and for anything not fitting in those two, video must have black stripes/bars. Do the m4v files have the same restrictions? Or the HandBrake just copied 16:9 ratio info into the file, ignoring that the video was also cropped (which changed the aspect ratio of the output).
I have no idea what you're talking about and all your assumptions are wrong. HandBrake stores the correct aspect ratio in the output file. HandBrake does not copy a ratio from the DVD, it calculates it from the dimensions. And cropping has absolutely *no* impact on pixel aspect ratio.
Carlsen
Posts: 8
Joined: Sun Feb 18, 2007 9:18 pm

Re: Correcting the aspect ratio for anamorphic video

Post by Carlsen »

For whatever reason, I have the same issue when trying to playback anamorphic files on the xbxo360. Weird thing is, this only occurs with the files that have been converted using Sharktooths high profile settings. When ripping anamorphic using the Apple preset, everything is fine. And ALL the files look great in VLC, by the way - just not on the xbox. *shrugs*
amiliv
Posts: 10
Joined: Sun Sep 09, 2007 5:36 am

Re: Correcting the aspect ratio for anamorphic video

Post by amiliv »

It would be very much appreciated if somebody could give me step by step instructions (and exact software I'd need) to fix the encoded files so that they are played back in correct aspect ratio.
Um it's not fixing the files -- it's working around a QuickTime bug.
Speaking of bugs, it looks like latest QuickTime update (as of couple of days ago) fixed things. QT (of m4v file) and DVD player (of original DVD) playbacks no longer differ (as they used to).
Related question is, why didn't HandBrake store correct aspect ratio info in the output file? I know that DVD only has a flag telling if the video is 4:3 or 16:9, and for anything not fitting in those two, video must have black stripes/bars. Do the m4v files have the same restrictions? Or the HandBrake just copied 16:9 ratio info into the file, ignoring that the video was also cropped (which changed the aspect ratio of the output).
I have no idea what you're talking about and all your assumptions are wrong. HandBrake stores the correct aspect ratio in the output file. HandBrake does not copy a ratio from the DVD, it calculates it from the dimensions. And cropping has absolutely *no* impact on pixel aspect ratio.
I was speaking of aspect ratio of entire image (as outputted on the screen), not the pixel aspect ratio. The former is function of the later. The former changes when you crop, the later does not. For example, 640:480 image has aspect ratio of 4:3, and let assume the aspect ratio of the pixels was 1:1 (in other words, normal non-anamorphic video). If you crop the image to 640:360, aspect ratio of the pixels is still the same, just as you said (in this example, 1:1), but the aspect ratio of the image on the screen is now 16:9.

If the info I found on DVD specs was correct, DVD can not store an arbitrary aspect ratio information (as in floating point value). It only has a flag (boolean value) telling if the 720x480 video should be displayed in 4:3 or stretched to 16:9. For example, you can't specify on DVD that aspect ratio is 1.85:1 or 2.40:1. Instead they are encoded in 16:9 with black stripes at top/bottom (letterbox). For example, Goldmember (as released for DVD) was rendered in 720x368, black stripes were added at top/bottom to resize it to 720x480 and 16:9 bit was set to true. That was the only way to encode wide cinematic feature (2.31:1 aspect ratio in this case) on DVD media.
jbrjake
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Re: Correcting the aspect ratio for anamorphic video

Post by jbrjake »

amiliv wrote:Speaking of bugs, it looks like latest QuickTime update (as of couple of days ago) fixed things. QT (of m4v file) and DVD player (of original DVD) playbacks no longer differ (as they used to).
You are wrong. They merely replaced it with another bug that ignores the initial state of the Clean Aperture widget in the video properties.
Related question is, why didn't HandBrake store correct aspect ratio info in the output file? I know that DVD only has a flag telling if the video is 4:3 or 16:9, and for anything not fitting in those two, video must have black stripes/bars. Do the m4v files have the same restrictions? Or the HandBrake just copied 16:9 ratio info into the file, ignoring that the video was also cropped (which changed the aspect ratio of the output).
I have no idea what you're talking about and all your assumptions are wrong. HandBrake stores the correct aspect ratio in the output file. HandBrake does not copy a ratio from the DVD, it calculates it from the dimensions. And cropping has absolutely *no* impact on pixel aspect ratio.
I was speaking of aspect ratio of entire image (as outputted on the screen), not the pixel aspect ratio. The former is function of the later. The former changes when you crop, the later does not. For example, 640:480 image has aspect ratio of 4:3, and let assume the aspect ratio of the pixels was 1:1 (in other words, normal non-anamorphic video). If you crop the image to 640:360, aspect ratio of the pixels is still the same, just as you said (in this example, 1:1), but the aspect ratio of the image on the screen is now 16:9.
What are you talking about? I still don't understand your question, as HandBrake *does* store correct aspect ratio info in the output file, despite your claims to the contrary. Cropping has absolutely zero effect on any of this. Pixel aspect ratio stays the same regardless, so display width never changes with unscaled video.
If the info I found on DVD specs was correct, DVD can not store an arbitrary aspect ratio information (as in floating point value). It only has a flag (boolean value) telling if the 720x480 video should be displayed in 4:3 or stretched to 16:9. For example, you can't specify on DVD that aspect ratio is 1.85:1 or 2.40:1. Instead they are encoded in 16:9 with black stripes at top/bottom (letterbox). For example, Goldmember (as released for DVD) was rendered in 720x368, black stripes were added at top/bottom to resize it to 720x480 and 16:9 bit was set to true. That was the only way to encode wide cinematic feature (2.31:1 aspect ratio in this case) on DVD media.
Why are you lecturing me about things I obviously already know?
amiliv
Posts: 10
Joined: Sun Sep 09, 2007 5:36 am

Re: Correcting the aspect ratio for anamorphic video

Post by amiliv »

I have no idea what you're talking about and all your assumptions are wrong. HandBrake stores the correct aspect ratio in the output file. HandBrake does not copy a ratio from the DVD, it calculates it from the dimensions. And cropping has absolutely *no* impact on pixel aspect ratio.
Sigh... There's aspect ratio of the image, there's aspect ratio of the pixels (for anamorphic images). Two different things, two different numbers. I guess I'm attempting to explain what's on my mind using too many words. If you read my reply again, you'll see we both wrote the same thing, cropping does not change pixel aspect ratio. I got my answer from your first reply, which was: HandBrake is storing correct info in the file, there was/is bug in QuickTime. I'm not attempting to prove different. I haven't wrote anything in my reply to you that could be interpreted as if I was claiming bug in HandBrake (there was in my original question, but that was just the question, not assertion).
Why are you lecturing me about things I obviously already know?
Was not my intention to lecture you. Just wanted to clarify some of the stuff I previously wrote. I apologize if it sounded like lecturing to you. Though, I must say, I don't understand hostility on your part. I'm not attacking you, I'm not attempting to prove you wrong, and I'm definitely not attempting to lecture you or assert anything about your level of knowledge. Enjoy the rest of the day, I'll do the same. Once again, thanks for giving me a complete and good answer to my original question.
jbrjake
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Re: Correcting the aspect ratio for anamorphic video

Post by jbrjake »

amiliv wrote: I haven't wrote anything in my reply to you that could be interpreted as if I was claiming bug in HandBrake (there was in my original question, but that was just the question, not assertion).
Your question was based on totally invalid assertions. It's quite the rhetorical trick to start off with the bare assertion fallacy and then reinforce it with a binary false dilemma:
why didn't HandBrake store correct aspect ratio info in the output file? [THIS IS NOT TRUE] <snip> Do the m4v files have the same restrictions? [THIS IS NOT TRUE] Or the HandBrake just copied 16:9 ratio info into the file, ignoring that the video was also cropped (which changed the aspect ratio of the output).[THIS IS NOT TRUE]
And I still have no idea what you were asking, since HB *did* store the correct aspect info, m4v *doesn't* have any restrictions on aspect ratio, and HB *didn't* just copy a 16x9 ratio into the file, and since aspect ratio information is *stored in pixel ratio form* cropping has zero affect on the information that's stored. Everything you premised your questions on is incorrect.
I don't understand hostility on your part.
You started a thread to falsely claim HB doesn't do anamorphic correctly and asked if it was a technical limitation or if we were just being lazy and thoughtlessly copying data... I don't want other people thinking you know what you're talking about. It's about stopping FUD, so six months from now we're not hearing "So I read on their forum that HandBrake doesn't do anamorphic correctly..."
amiliv
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Joined: Sun Sep 09, 2007 5:36 am

Re: Correcting the aspect ratio for anamorphic video

Post by amiliv »

You started a thread to falsely claim HB doesn't do anamorphic correctly and asked if it was a technical limitation or if we were just being lazy and thoughtlessly copying data... I don't want other people thinking you know what you're talking about. It's about stopping FUD, so six months from now we're not hearing "So I read on their forum that HandBrake doesn't do anamorphic correctly..."
When I asked the original question, I did not know where the problem was. I did not know if it was problem with my players (QuickTime and iTunes) or with HandBrake. Sure, I should have phrased my questions differently. However, you are attempting to make it as if I was not looking for answers, but rather as if my sole intention was to spread false information. Calm down. Not everybody around you is going to stub you in the back. I searched the forums for the problem I had, and haven't found anything that said it was problem with either QuickTime or HandBrake. Now there's thread (this one) that contains correct answer. If people can't read answers, it's not me spreading fud.

And, BTW, please do not put words in my mouth. I asked about things I did not know, never labeled anybody as "lazy". If you see people asking questions as attacking you, may I suggest delegating answering to somebody else less paranoid?
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