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#299288 - 11/06/2007 19:48 Stupid video encoding question
CrackersMcCheese pooh-bah Registered: 14/01/2002 Posts: 2489	Ok I'm about to make a fool of myself as this is probably totally obvious but here goes! I recorded a video clip and its PAL 16:9 aspect ratio. Its also 720x576. This is where I'm lost - 720x576 isn't a 16:9 ratio. Or is it? I want to encode it to mp4 and resize it but I'm unsure what to divide my numbers by. Sorry for sounding a bit thick!
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#299289 - 11/06/2007 19:53 Re: Stupid video encoding question [Re: CrackersMcCheese]
schofiel carpal tunnel Registered: 25/06/1999 Posts: 2993 Loc: Wareham, Dorset, UK	No, no - don't be so hard on yourself. You're not thick. You just haven't had enough beers yet. _________________________ One of the few remaining Mk1 owners... #00015
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#299290 - 11/06/2007 19:54 Re: Stupid video encoding question [Re: schofiel]
schofiel carpal tunnel Registered: 25/06/1999 Posts: 2993 Loc: Wareham, Dorset, UK	Oh 'eck - I've been rumbled! _________________________ One of the few remaining Mk1 owners... #00015
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#299291 - 11/06/2007 19:59 Re: Stupid video encoding question [Re: CrackersMcCheese]
wfaulk carpal tunnel Registered: 25/12/2000 Posts: 16706 Loc: Raleigh, NC US	Without seeing your clip, you probably have non-square pixels in the video file. Other possibilities include the possibility that you've recorded black bars at the top and bottom. What tool are you using to reencode it? Chances are it will see the aspect ratio information in the file (especially if it plays properly in your media player) and do the right thing. _________________________ Bitt Faulk
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#299292 - 11/06/2007 20:07 Re: Stupid video encoding question [Re: wfaulk]
CrackersMcCheese pooh-bah Registered: 14/01/2002 Posts: 2489	Its a file recorded from freeview (digital TV) and it was a widescreen transmission - no black bars top and bottom. It plays in widescreen on VLC Media Player and WMP. The tool I'm using to re-encode it TmpgEnc Xpress 4. Looking again, it says its Pixel 16:11 - but 720x576 still isn't that ratio.
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#299293 - 11/06/2007 20:08 Re: Stupid video encoding question [Re: schofiel]
CrackersMcCheese pooh-bah Registered: 14/01/2002 Posts: 2489	Happy Birthday Rob!!
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#299294 - 11/06/2007 20:10 Re: Stupid video encoding question [Re: CrackersMcCheese]
andy carpal tunnel Registered: 10/06/1999 Posts: 5916 Loc: Wivenhoe, Essex, UK	Did you record that video clip yourself at the race ? _________________________ Remind me to change my signature to something more interesting someday
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#299295 - 11/06/2007 20:13 Re: Stupid video encoding question [Re: andy]
CrackersMcCheese pooh-bah Registered: 14/01/2002 Posts: 2489	I wish! No, its from ITV's coverage on my Hauppauge Nova-t card. Don't worry - its not intended for public distribution so Bernie won't be chapping at my door! p.s. I've not forgotten about your empeg/Anoface!
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#299296 - 11/06/2007 20:30 Re: Stupid video encoding question [Re: CrackersMcCheese]
schofiel carpal tunnel Registered: 25/06/1999 Posts: 2993 Loc: Wareham, Dorset, UK	Thank you, kind sir! Glad to be back here. _________________________ One of the few remaining Mk1 owners... #00015
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#299297 - 11/06/2007 21:20 Re: Stupid video encoding question [Re: CrackersMcCheese]
wfaulk carpal tunnel Registered: 25/12/2000 Posts: 16706 Loc: Raleigh, NC US	Quote: it says its Pixel 16:11 - but 720x576 still isn't that ratio. Right. What it's telling you is that the pixels themselves are rectangles in a ratio of 16:11. Basically, it means that each 11 of the 720 pixels, are as wide as 16 of the 576 pixels are tall. So, to translate to square pixels, multiply 720 by 16/11, which gets you a little over 1047. Then divide that by 576 and you get 1.818. Whereas 16 divided by 9 is 1.777, which is reasonably close. _________________________ Bitt Faulk
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#299298 - 12/06/2007 18:58 Re: Stupid video encoding question [Re: wfaulk]
andym carpal tunnel Registered: 17/01/2002 Posts: 3996 Loc: Manchester UK	Quote: Quote: it says its Pixel 16:11 - but 720x576 still isn't that ratio. Right. What it's telling you is that the pixels themselves are rectangles in a ratio of 16:11. Basically, it means that each 11 of the 720 pixels, are as wide as 16 of the 576 pixels are tall. So, to translate to square pixels, multiply 720 by 16/11, which gets you a little over 1047. Then divide that by 576 and you get 1.818. Whereas 16 divided by 9 is 1.777, which is reasonably close. Given that the active picture dimensions of a PAL picture are actually 702x576 (or 704x576 for NTSC) then your calculations work out correctly. _________________________ Cheers, Andy M
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#299299 - 12/06/2007 19:03 Re: Stupid video encoding question [Re: andym]
andym carpal tunnel Registered: 17/01/2002 Posts: 3996 Loc: Manchester UK	From wikipedia: Quote: 702 is the width of analogue, not digital; the definition of what is 4:3, and what is 16:9, derives from here. _________________________ Cheers, Andy M
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#299300 - 13/06/2007 06:11 Re: Stupid video encoding question [Re: CrackersMcCheese]
LittleBlueThing addict Registered: 11/01/2002 Posts: 612 Loc: Reading, UK	You may want to grab avidemux - good little app for transcoding... _________________________ LittleBlueThing Running twin 30's
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