Welcome to the MacNN Forums.

JohnM15141 · Apr 7, 2003, 06:01 AM

Someone educate me about DVD Aspect Ratios. When I travel, I watch a lot of DVD's on my PowerBook. I've got a 17" PB with the magnificant widescreen 1440X900 pixels of resolution. On some places on the web I read that this is 16:10. When I watch DVD with widescreen versions I still have black bars on either side of the screen. Whats up with that?

What is the aspect ratio of a widescreen DVD?

Why doesn't it fit on my 17" PB Screen?

What are the Aspect Ratio's of DVD's?

What are the aspect ratios of TV's Vs. Movie Screens?

I could do days worth of research myself but I'm guessing someone out there is a Videophile and has done this research and can answer my question in one post

Now, mind you, DVD's look great on my 17" PB so much so that I rarely hook it up to the Hotel room TV(Like I did with my iBook each and every time), 'cause it looks much better on my PowerBook. I just want to know whats going on and why DVD's don't quite fit my 17"PB's screen...??

hlouey · Apr 7, 2003, 06:13 AM

Originally posted by JohnM15141:
Someone educate me about DVD Aspect Ratios. When I travel, I watch a lot of DVD's on my PowerBook. I've got a 17" PB with the magnificant widescreen 1440X900 pixels of resolution. On some places on the web I read that this is 16:10. When I watch DVD with widescreen versions I still have black bars on either side of the screen. Whats up with that?

What is the aspect ratio of a widescreen DVD?

Why doesn't it fit on my 17" PB Screen?

What are the Aspect Ratio's of DVD's?

What are the aspect ratios of TV's Vs. Movie Screens?

I could do days worth of research myself but I'm guessing someone out there is a Videophile and has done this research and can answer my question in one post

Now, mind you, DVD's look great on my 17" PB so much so that I rarely hook it up to the Hotel room TV(Like I did with my iBook each and every time), 'cause it looks much better on my PowerBook. I just want to know whats going on and why DVD's don't quite fit my 17"PB's screen...??

http://www.thedigitalbits.com/articles/anamorphic/

Enjoy :-)

This is the BEST site for explaining the difference btw aspect ratios

Henry

AssassyN · Apr 7, 2003, 06:27 AM

Well, although the 17" PB had a "widescreen" aspect ratio, it's not exactly in the ratio of "widescreen" DVD's. The PBs screen is 16:10, where a typical "widescreen" DVD is 4:3, thus the slight difference making the small black bars on the sides.

Gromet · Apr 7, 2003, 06:42 AM

OK, I was watching Red dragon (widescreen) last night on my 17" and there were no black bars on the sides, just small (Mabye 1/2 inch bars on the top and bottom. Not bad and not distracting but it would be nice to get a true full screen movie. The picture quality was awesome but there were no bars on the sides.

Gromet.

vandelay · Apr 7, 2003, 06:57 AM

Movie aspect ratios vary mostly between 1.85:1 and 2.35:1.Depending on the particular movie you get different sized black bars on your display.

mattnl · Apr 7, 2003, 07:57 AM

Originally posted by AssassyN:
Well, although the 17" PB had a "widescreen" aspect ratio, it's not exactly in the ratio of "widescreen" DVD's. The PBs screen is 16:10, where a typical "widescreen" DVD is 4:3, thus the slight difference making the small black bars on the sides.

that's not quite right. the pb ratio is 16:10, but a typical movie is not 4:3, it's 16:9. 4:3 is the TV aspect ratio.

Patcarla · Apr 7, 2003, 08:09 AM

Originally posted by mattnl:
that's not quite right. the pb ratio is 16:10, but a typical movie is not 4:3, it's 16:9. 4:3 is the TV aspect ratio.

Yes, DVD come in two format:
Full screen :4:3 adapted for most of the TV formats
Wide screen : 16:9 closest to cinema screen (cinmescope format)

cambro · Apr 7, 2003, 08:24 AM

Regarding aspect ratios....

NO NEED to spend hours doing research. The ratio is just that...a ratio of width to height.

If the fraction 1440/900 (written 1440:900 if you like) is the width to heigth ratio of your 17' screen, then just reduce this fraction...or, if you are intested in whether or not it is "16/10" (which would be expressed as 8/5 in a more reduced form) you can do this:

1440:900 is the same as 144:90 (divide both top and bottom by 10).

144/90 = x/10

solve for x and you get that your screen is 16/10! Ratios are useful because you can multiply the width and height by the same value and the screen will be proportioned exactly the same but just bigger...8:5 = 16:10 = 144:90 = 1440:900

Anyway, if whatever video format you are interested in has a ratio that is exactly equal to the ratio of your screen, then it will fit perfectly in that screen provided the software renders it correctly. If it differs, then depending on whether the width or height in the video is bigger, the bars will be on the other side (if the video has a larger numerator = width, then black bars will be at top...hence your blockbuster movie on your tv with black bars on top and bottom).

Ahh, the joys of algebra.

Eug · Apr 7, 2003, 08:29 AM

TV is 4:3 = 1.333:1.
CRTs are 4:3.
Some laptops (12" PowerBook) are 4:3.

The 17" PowerBook is 16:10 = 1.6:1

DVDs are often 16:9 = 1.78:1, but that doesn't mean the movies are.

Movies are often 2.35:1 or 1.85:1 or whatever. (1.78:1 is close enough to 1.85:1 though.) Some movies are 1.66:1 even. The hacked "modified to fit your screen" movies are 1.33:1, but cut out a lot of video most of the time to make it fit.

Aykew · Apr 7, 2003, 01:07 PM

I'm still fairly confused as far as dvd aspect ratios go (anamorphic is a term that still eludes me...) but here's my guess: the dvd you were trying to view was a widescreen movie encoded in 4:3, meaning the black bars are actually part of the image itself, instead of being generated by the dvd player. So the DVD player sees that if it were to strech the movie all the way to the horizontal edges of the screen, it would be cutting off the top and bottom of the image. In this case, those parts of the image aren't important, but the DVD player doesn't know that.

I'll bet if you get a dvd that doesn't have those bars encoded (is that what anamorphic means?), it'll strech the video all the way across the screen. (BTW... Since the powerbook has a 16:10 ratio, sounds like 1.66:1 is the best match, with just tiny black bars on the top and bottom. Someone pop in Disney's Tarzan, little mermaid, or Hunchback... I think they're all in 1.66. Tell us how it looks!)

Eug · 02:49 PM

anamorphic is a term that still eludes me...

Oversimplification:

A 4:3 image fits best on a 4:3 TV. To get a widescreen movie on that TV one do a couple of things.

1) Letterbox widescreen. Create a 4:3 image with black bars at the top and bottom hard-encoded into it. Unless you zoom the image, you will always have black bars. However, if you do zoom the image on a 4:3 TV, you'll remove the top and bottom black bars, but you'll also cut off the sides of the picture.

2) Anamorphic widescreen. Vertically, the whole resolution is used for the movie. The image doesn't include those hard-encoded black bars. However, anamorphic widescreen expands the horizontal size. Thus the vertical image would fill up a TV vertically (without black bars), but if displayed properly the image is too wide to fit on a 4:3 TV.

If you own a 4:3 TV and an anamorphic widescreen movie:

1) If you tell the DVD player you have a 16:9 widescreen TV (instead of a 4:3 TV), the DVD player will keep the normal vertical size and expand the horizontal size. However, your TV will cram all of this extra horizontal size onto its narrower horizontal screen, and thus everything will look squished sideways. People will look tall and skinny on that 4:3 TV.

2) If you tell the DVD player you have a 4:3 TV, the DVD player will remove vertical resolution from the image to compensate for the effect I mentioned above. Thus you'll get the image squished vertically, to bring those tall skinny people back to normal dimensions, but then you get those black bars at the top and bottom.

In other words, to display an anamorphic widescreen movie with proper dimensions on a 4:3 TV, the DVD player if set correctly will create a letterbox widescreen image on the fly. So, watching anamorphic movies on a 4:3 TV gives you no real advantage. The way around this is to buy a 16:9 TV.

sonoronos · Apr 7, 2003, 02:08 PM

Hello,

Wow Aykew, you've poked the hornets nest here. If you were to ask a bunch of cinematographers what "anamorphic meant", there would be more heated passions than you can imagine! Anamorphic projection goes back a looong time ago, to the first Panavision and Cinemascope movies.

I would recommend this book for reading:

Wide Screen Movies: A History and Filmography of Wide Gauge Filmmaking by Robert E. Carr, R. M. Hayes

It's fascinating stuff, albeit nerdy.

Anyways, the bottom line is that all cinematographers want MORE RESOLUTION (not much different from us, eh?) First there was 8mm, then 16mm, then a whole slew of crappy formats until 35mm. When 35mm rolled around, industry executives were telling people, "there's no need for anything other than 35mm". Unfortunately, directors were screaming for wider and wider images.

Cinematographers, being a tinkery bunch, started spreading the imaqe on 35mm wider and wider, until it started over-writing the audio tracks (then written on the film itself), and eventually the audio tracks disappeared, and the whole image was spread from sprocket to sprocket on the 35mm film. Some people started running the film _horizontally_ to get wider and wider aspect ratios. Unfortunately, this started getting expensive, as each frame took as much as twice the film as standard 1.33:1 35mm, and over ten thousand frames, that's a LOT more film (and money).

Hence, Cinemascope and Panavision were invented - a system of lenses and mirrors that took a _wide_ image at 2.35:1 aspect ratio and optically compressed it all onto a 1.33:1 spot on the negative. This was and is the only anamorphic standard. When projected, the 35mm compressed image was uncompressed with another anamorphic lens, and you got your 2.35:1 aspect ratio back. With this system, cinematographers got the "wide" look they wanted and movie producers didn't have to waste so much money on film.

In today's world of digital transfer and direct projection TV's, anamorphic doesn't mean anything. It really doesn't. Heck, you're shuffling bits around, you might as well argue about codecs or something.

AssassyN · Apr 7, 2003, 04:27 PM

Originally posted by mattnl:
that's not quite right. the pb ratio is 16:10, but a typical movie is not 4:3, it's 16:9. 4:3 is the TV aspect ratio.

Ahh! It was too early in the morning! I knew that, doh! Thanks for the correction...my apologies!

iDaver · Apr 7, 2003, 05:13 PM

To simplify:

If you want to fill a standard TV screen, get "full-screen" DVDs.

If you want to fill the WIDTH of a (16x10) Powerbook screen, get "wide-screen" DVDs.

Personally, I hate full-screen DVDs cause it feels like you have blinders on, compared to wide-screen, which is the way the film maker intended the film to be viewed.

AssassyN · Apr 7, 2003, 05:37 PM

Originally posted by iDaver:
Personally, I hate full-screen DVDs cause it feels like you have blinders on, compared to wide-screen, which is the way the film maker intended the film to be viewed.

THANK YOU!!! Finally someone who understands!!! The problem is that 99% of recent & good DVD's *only* come widescreen! Argh! I would MUCH rather have the entire screen filled up than view it however some director wanted me to!

iDaver · Apr 7, 2003, 11:29 PM

Originally posted by AssassyN:
THANK YOU!!! Finally someone who understands!!! The problem is that 99% of recent & good DVD's *only* come widescreen! Argh! I would MUCH rather have the entire screen filled up than view it however some director wanted me to!

Ahem, uh, read my statement again and you'll see I'm of the other opinion. Wide screen movies are much preferable to the old 4 to 3 ratio of a standard TV.

You're right, most DVDs are presented wide-screen. I think that's what most people prefer, although I have friends who complain about the black bars at the top and bottom of their current TV sets. The HDTV format aims to eliminate (somewhat) this problem.

AssassyN, I'm surprised you would prefer 4 to 3, seeing that you have both a wide PowerBook and a Cinema Display on which to watch DVDs.

Dave

AssassyN · Apr 7, 2003, 11:36 PM

Heh, I apologize for misreading your post! And I was a bit premature in saying I prefer fullscreen DVD's...it's just I just got my 17" PB (which allows me to use my 23" HD Display) 4 days ago and I've only watched one DVD on the PB and none on the HD Display yet, and even on the PB the bars irritated me...I'd much rather it fill the screen, but at least the bars are relatively small.

And too, fullscreen DVD's fill up the screen on any and every TV and every house and party you go to, while widescreen HDTV's are few and far between right now. If a widescreen monitor/TV is around, sure I prefer a widescreen DVD, but it's just that so many monitors and TV's aren't.

In my house w/ this new display, I love my widescreen DVD's, but on non-widescreen displays I'd certainly rather it fill up the screen regardless of any loss in "cinematic effect", b/c aren't black bars a loss of that in the first place?

iDaver · Apr 7, 2003, 11:46 PM

Originally posted by AssassyN:

In my house w/ this new display, I love my widescreen DVD's, but on non-widescreen displays I'd certainly rather it fill up the screen regardless of any loss in "cinematic effect", b/c aren't black bars a loss of that in the first place?

No arguement here. You make some good points.

I am slowly building up a collection of DVDs and I only buy wide-screen versions. While I have a regular 4/3 TV now, I anticipate going to HDTV within a couple of years and would hate to then have a bunch of 4/3 DVDs.

I like the wide-screen aspect so much that I rarely watch DVDs on the TV but prefer watching with my TiBook in my lap and headphones on. Try it with your new 17". I'll bet it's great! Of course if you're in a social situation, it's hard for the whole family or group of friends to watch the PowerBook on your lap. 'Course if it's your girlfriend...that might not be so bad.

iDaver · Apr 8, 2003, 12:03 AM

Getting back to the original post in this thread, by JohnM; sounds like even with wide-screen DVDs, he's getting black bars left and right. I'm baffled by that one, unless he's not viewing at maximum size. Hit command-3, John.

JohnM15141 · Apr 8, 2003, 12:13 AM

Originally posted by iDaver:
Getting back to the original post in this thread, by JohnM; sounds like even with wide-screen DVDs, he's getting black bars left and right. I'm baffled by that one, unless he's not viewing at maximum size. Hit command-3, John.

I was watching the DVD "Office Space" in a wide screen presentation(I`m not sure what aspect ratio) when I got Black bars on either side of the screen. I noticed when I adjust the screen resolution to a lower resolution the film fits the screen but of course since the lower resolution is only emulated on the 17 inch powerbook screen the picture looks fuzzier.

I`m not near my Laptop at the moment but when I get back to my Hotel room I`ll put that DVD in and try command-3

The responses to this thread have been extremely informative, I now believe I can sit down and have a decent conversation about this topic.

sonoronos · Apr 8, 2003, 01:23 AM

Well, looks like it's about time for the 2006x854 23" LCD laptop.

DVD Plaza · Apr 8, 2003, 02:16 AM

Originally posted by AssassyN:
In my house w/ this new display, I love my widescreen DVD's, but on non-widescreen displays I'd certainly rather it fill up the screen regardless of any loss in "cinematic effect", b/c aren't black bars a loss of that in the first place?

You're misunderstanding how it works. Think of it in a really really basic sense:

Movies are RECTANGLE - in other words, they are WIDE.

TVs are square. To fill the entire screen they CHOP THE SIDES OF THE MOVIE OFF. This makes it square movie and therefore fills your TV - but you have lost a heap of the movie. If three people were standing alongside each other in a movie, you would end up with 1.5 of them for example.

Black bars do NOT loose picture - if you put a rectangle inside of a square you end up with left over space - because a square is taller than a rectangle. What happens with that left over space? It's black - that's why you see black bars on a normal TV, because you're watching a rectangle movie inside a square TV. The black bars do NOT cover anything, they are LEFT OVER space.

Hope this explanation makes sense

naphtali · Apr 8, 2003, 02:37 AM

Sorry to be nitpicky but aren't TV's 4:3? That doesn't sound too much of a square to me...

iDaver · Apr 8, 2003, 02:38 AM

Originally posted by DVD Plaza:

Black bars do NOT loose picture - if you put a rectangle inside of a square you end up with left over space - because a square is taller than a rectangle. What happens with that left over space? It's black - that's why you see black bars on a normal TV, because you're watching a rectangle movie inside a square TV. The black bars do NOT cover anything, they are LEFT OVER space.

I think what AssassyN and some others object to is that a wide-screen movie on a square picture tube is simply a smaller picture. You are not utilizing every square inch of the screen, therefore the black bars are annoying wasted space. This doesn't bother me as I prefer seeing the whole wide-screen image as the director intended, but I see the point of those who disagree.

It took Steven Speilberg many years to agree to bring ET to video because (among other things) he didn't want to cut off the sides of the movie frame to fit a TV screen.

DVD Plaza · Apr 8, 2003, 02:49 AM

I said I was providing a "really really basic" explanation, in the hope it would make more sense. Hence using the word square for 1.33:1 (or 4:3) and rectangle for 1.66:1, 1.85:1, and 2.35:1. Wouldn't make sense to offer a basic explanation but then instead provide a technical one would it?

DVD Plaza · Apr 8, 2003, 02:51 AM

*duplicate*

SMacSteve · Apr 8, 2003, 08:34 AM

Originally posted by AssassyN:
Well, although the 17" PB had a "widescreen" aspect ratio, it's not exactly in the ratio of "widescreen" DVD's. The PBs screen is 16:10, where a typical "widescreen" DVD is 4:3, thus the slight difference making the small black bars on the sides.

You have no idea what you're talking about. A 4:3 is the typical TV screen ratio and HDTV ratio is 16:9. The 16:10 is slightly taller than the 16:9 and most movies are filmed in ratios of 2.35:1 or larger. This makes the information wider than the 16:10 can diplay without losing information on the sides so you get black bars on the top and bottom to make up for the wider ratio.

bluejam · Apr 8, 2003, 09:29 AM

Many DVD's have the 16:9 version on one side and the modified 4:3 version on the other side. If there are two discs, they could be on separate discs. John, are you sure you had the correct version(side or disc)? Also, the studios are known to make errors on DVD's...Saying it is widescreen format on the box but in reality, it is not.

BTW, Im surprised so many with $3,300 laptop computers don't have better TV's. You know, you can get a nice HDTV widescreen for a lot less than a 17" Powerbook these days.

Aykew · Apr 8, 2003, 09:42 AM

Originally posted by JohnM15141:
I was watching the DVD "Office Space" in a wide screen presentation(I`m not sure what aspect ratio) when I got Black bars on either side of the screen. I noticed when I adjust the screen resolution to a lower resolution the film fits the screen but of course since the lower resolution is only emulated on the 17 inch powerbook screen the picture looks fuzzier.

Ok, I found a page that seems to support my thought from my post a little higher up. (non-anamorphic widescreen DVDs are really encoded in 4:3 with black bars encoded in with the video.) Take a look at the 4th example down the page... I think that's what's happening to the powerbook users. The Office Space DVD is non-anamorphic, so no matter what you press, you'll always have the black bars to the side because the DVD Player thinks the picture is too tall for the video to touch the horizontal edges.

Eug · Apr 8, 2003, 02:18 PM

Ok, I found a page that seems to support my thought from my post a little higher up. (non-anamorphic widescreen DVDs are really encoded in 4:3 with black bars encoded in with the video.) Take a look at the 4th example down the page... I think that's what's happening to the powerbook users. The Office Space DVD is non-anamorphic, so no matter what you press, you'll always have the black bars to the side because the DVD Player thinks the picture is too tall for the video to touch the horizontal edges.

Some software, TVs, or DVD players, allow one to zoom the picture, to get around this limitation in certain discs.

My DVD player is able to zoom and upsample the picture as well. Not as good as anamorphic, but much better than plain zoom.

Im surprised so many with $3,300 laptop computers don't have better TV's. You know, you can get a nice HDTV widescreen for a lot less than a 17" Powerbook these days.

I agree. I'd rather have a $2000 laptop and a $2000 TV than a $3500 laptop and $500 TV.

JohnM15141 · Apr 8, 2003, 05:19 PM

I think you hit the Nail on the head concerning this particular DVD. I adjusted the Hue of my Background so that the Black was more purple. I could then see the Black Bars inserted by DVD Player and the Black Bars impressed into the DVD's Playback. It does appear that the DVD Player is inserting the black bars on the side to fit the 4:3 DVD Playback onto my 16:10 Display. So even though I though I was watching a Widescreen Movie it was actually a 4:3 Video with Black bars inserted top and bottom for the Widescreen Presentation.

I can now say from all the fine info in this thread that the Office DVD is a letterbox Widescreen Presentation(Thanks Eug!) This is defined as a Widescreen movie placed inside 4:3 image with black bars at the top and bottom to make it fit standard TV's.

I played this same DVD in a Window and the black bars on either side were removed because they were unneccesary.

I watched The Army OF Darkness DVD with true Anamorphic Widescreen and it does fit edge to edge on the 17" PB Screen. It looked better than most TV's

By the way, "hey Bluejam," a Plasma TV is tops on my Wishlist now that I have a 17"PB which had been number one all the way up to it's delivery

Originally posted by Aykew:
Ok, I found a page that seems to support my thought from my post a little higher up. (non-anamorphic widescreen DVDs are really encoded in 4:3 with black bars encoded in with the video.) Take a look at the 4th example down the page... I think that's what's happening to the powerbook users. The Office Space DVD is non-anamorphic, so no matter what you press, you'll always have the black bars to the side because the DVD Player thinks the picture is too tall for the video to touch the horizontal edges.