Aspects of Aspect Ratioby jarrow

A friendly, thorough attempt to take the “ass” out of aspect ratio

Note: This is an NTSC presentation. PAL source is not addressed here.

Objectives

Define and explain aspect ratio Provide useful tips and math to aid vidders in

dealing with aspect ratios Discuss how to deal with multiple aspect ratios

in one vid

As time allows: Find successful ways to export for cons Look at platform-specific problems (PC and

Mac) with tech to fix/handle aspect ratios

Please remember!

We all enter this conversation with different levels of prior knowledge, understanding, and experience.

We use different computer systems, software, and processes.

Vidding is hard. Math is hard. Aspect Ratio is hard.

We are here to help each other. We may not have time to get to what you most

need to know / want to ask.

Main Takeaways

There are 3 aspect ratios: Fullscreen, Widescreen, and Movie Scope.

720 x 480 is not your friend. (Sorry.)If you put your vid in the correct aspect

ratio before editing, you will have an easier time “seeing” the correct ratio when exporting.

Letterboxing can be more harmful than helpful.

Contents

1) The Basic Basics What is aspect ratio? Why 720 x 480 source is always wrong

2) The Basic Aspect Ratios Define and describe the 3 aspect ratios Resizing sources to the correct ratio

3) Letterboxing is Deceiving Why you should remove letterboxing from source How to resize movies with letterboxing to a right ratio

4) Getting it Right Set preview settings to match source and export

settings

Contents

5) Using Mixed Aspect Ratios Adjusting 1 source (with cropping) to match the other Adjusting multiple sources (with cropping) to a new

framesize 6) Exporting for Cons

How to get from square pixels to what will look right on a TV

7) Aspect Ratio Math Using division to fix ratios and determine frame sizes What is PAR and DAR?

8) Resources

Part 1: The Basic Basics

So, what IS aspect ratio?

Aspect ratio refers to the proportional ratio (length to width) of your video image.

Is your vid too long, too tall, or just right?

Basically, does it “look right”? Is it stretched?

A fickle beast

Because there are different types of media, there are different aspect ratios on the media we watch.

For vidders, aspect ratio becomes especially tricky when we need to change something from one ratio to another, use media with different ratios together, or even just get something from the wrong ratio into the right one.

But why is this such a chore?

We deal with aspect ratios because television broadcasts in rectangular pixels and our computer screens display square pixels.

We can look at the exact same thing in two places and, if we don’t adjust the aspect ratio, it will look “right” on one medium and “wrong” on the other. Great. You have to make a square peg fit in a round hole.

We face this problem when using source from a tv to make a vid for computer viewing, or when wanting to show a computer vid on a TV or at a con.

Your Theoretical Process

In theory, it’d be nice if your process went something like this*: 1) Acquire source 2) Correct source aspect ratio for computer viewing 3) Edit your vid 4) Release vid online at that same ratio 5) Adjust aspect ratio back to one for TV/cons if

necessary.

*But of course, do what you like.

Where to start?

To make a vid, you will generally get source from one of two places: Ripped DVDs Downloads

Typically, downloaded source is already in the correct aspect ratio for computer viewing. However, ripped DVDs are not. (They are in the right dimensions for TV viewing, which is different!) So, let’s start there.

Same Vid, Different Place

All source ripped from DVDs comes to us as 720 x 480.

Everything. These pixels will stretch to appear correctly (as rectangles) on a TV. But computers use square pixels, so we have to adjust the size so our source looks “right.”

Because these are dimensions for TV viewing, 720 x 480 will look “wrong” on a computer screen.

Every time.

720 x 480 is not your friend.

Right!848 x 480

wrong!

720x

480

So, what then?

The bottom line is this:

Bare source (no letterboxing) will never look right on a computer in the 720 x 480 we’re given. We have to fix it. Always.

So, first, you’ve got to know what the correct aspect ratio is supposed to be.

Part 2: The Basic Aspect Ratios

Basic Aspect Ratios

There are three basic aspect ratios for mainstream media:1) Fullscreen (4:3)2) Widescreen (16:9)3) Movie Scope (2.35:1)

Your vid, as a result, may be one of these ratios or a unique ratio that blends two or more of these. But, it will probably be one of these.

How do I know what ratio it is?

You can find this information on the back of your DVD packaging, most of the time. Look for the numerical ratio (4:3, 16:9, or 2.35:1)

Watch an episode on your computer, which probably has a wide screen monitor. If there are bars on the left and right sides, it’s in Fullscreen aspect ratio. If there are bars on top and bottom (or maybe none at all), it’s in Widescreen. If the bars are quite substantial and it’s a film, it may be Movie Scope.

Look at someone else’s vid for that show (a vidder you trust). What dimensions did they use?

Open an episode you know to be in the right ratio in an editing program or folder window – someplace where it can tell you the dimensions.

[Aspect] Ratios are Math (sorry.)

It’s a ratio, meaning there is math behind it. If your vid is fullscreen, it has a 4:3 ratio. This means your vid has 4 pixels of length for every 3 pixels of width. No matter the size, this will be true. If it is 400 pixels long, it will be 300 pixels wide. If it is 800 pixels long, it will be 600 pixels wide.

Notice that 4:3 is almost square (3:3 or 4:4 would be square). Widescreen, on the other hand, with a ratio of 16:9 is almost twice as long as it is wide (16:8 or 18:9 would be twice as long). It’s rectangular.

Movie Scope, with a ratio of 2.35:1 is more than twice as long as it is wide. It’s a much longer rectangle.

Fixing Aspect Ratio in 4:3(720 x 480 is wrong)

If you have a 4:3 (fullscreen) vid, 720 x 480 will be too wide, and everyone will look stretched horizontally.

Resize your vid to 640 x 480 to correct the aspect ratio. You are keeping it just as tall and squishing it back horizontally. No letterboxing is necessary.

480

720

480

640

Fixing Aspect Ratio in 16:9(720 x 480 is wrong)

If you have a 16:9 (widescreen) vid, 720 x 480 will be too narrow, and everyone will look stretched vertically.

Resize your vid to 848 x 480 to correct the aspect ratio. Again, you are keeping it just as tall, but now stretching your vid horizontally. No letterboxing is necessary.

Note: You can also keep the width of 720 and resize the height to 400. However, if your vid has interlacing, you can create problems if you adjust the height. Therefore, it is preferable to only adjust the width.

480

720

480

848

Characteristics: No Letterboxing

Fullscreen Widescreen Movie Scope

4:3 ratio (1.33) 16:9 ratio (1.77) 2.35:1 ratioPossible Dimensions*:

640 x 480 848 x 480 928 x 400

528 x 400 720 x 400 720 x 304

400 x 304 640 x 368 608 x 256

320 x 240 512 x 288 480 x 208Note: In several cases, ratios are not absolutely perfect. Dimensions are given to the nearest multiple of 16.

*This table applies to both native media source without letterboxing AND final vid exports for computer viewing without added letterboxing. Use these dimensions for distributing “clean” vids without black borders.

Part 3: Letterboxing is Deceiving

Um, there is letterboxing?

Just because there is letterboxing on your source already (typically, on movies), does not mean it will magically be right on your screen.

Any letterboxing from DVDs is there to make your source look right on a TV, not a computer screen! Plus, the amount of pixels added as letterboxing is not always the same from source to source.

Therefore, you have a choice. You can leave the letterboxing on or you can cut it off (software permitting). But I say, CUT IT OFF.

Not all it’s cracked up to be

There are definitely perks to stripping your source of any letterboxing (when possible). It is relatively straightforward to size your vid correctly

(using the table in the previous section). Any viewing program will automatically add black bars

(correctly!) as needed to properly display your vid when you watch it. Let the program do the work for you!

Letterboxing also adds size to your files because your vid is bigger than it would be otherwise. This is effectively “dead space” you could use to have a higher quality vid of the same file size.

The bottom line is: You have a much better chance of getting your vid to look right on a computer screen without any letterboxing on it.

Movie Source with Letterboxing

This is a ripped movie dvd that has letterboxing so it will look “right” on a widescreen television. A DVD ripper displays it in 720 x 480, as it does with everything. Its native source is Movie Scope aspect ratio (2.35:1), which is wider than regular widescreen (16:9). This is NOT RIGHT on a computer screen! It is too narrow.

Movie Source with Letterboxing

Left untouched, as ripped Resized to 16:9720 x 480 848 x 480 Squished! Correct!

Moral of Story: You can leave the letterboxing on a Movie Scope source, but now it needs to be in regular widescreen (16:9) sizing.

What it looks like at a Con

Fullscreen footage needs no added letterboxing to fit a con projector screen or DVD.

Widescreen footage needs letterboxing on top and bottom to fit con/DVD settings, which are made to look like Fullscreen (640 x 480) just stretched to 720 x 480.

*If resizing a movie, you have to add extra letterboxing.

Letterboxing on DVD Source

Remember: Fullscreen (4:3) and Widescreen (16:9) source will [most likely] not have any letterboxing on it when ripped.

Movie Scope (2.35:1) source with letterboxing should be resized to regular widescreen (16:9) dimensions to look right.

Therefore, you can use any of the Widescreen (16:9) dimensions from the No Letterboxing table to properly size your Movie Scope vid with original letterboxing.

My Two Cents

Whatever you decide – leave letterboxing or not – the best advice I have is to edit your vid while looking at the correct ratio. You may have to change it later to submit to cons – that’s fine. But if you get used to seeing it wrong, then you will have a much harder time getting it right later. Do not procrastinate!

Having said that, remember that if you are editing interlaced source, you need to de-interlace before doing any resizing.

Part 4: Getting It Right

Getting Your Vid in the Right Ratio(for computer viewing)

You have two basic options: 1) Crop and resize your vid clips before

editing, and set your project settings to match. *Highly recommended

2) Leave your source untouched and use your editing program to resize your vid

Option 1 can be used with the dimensions table from earlier. For Option 2, you may need an understanding of PAR, DAR, and rectangular pixels, as well as a deeper understanding of your editing program’s language and settings. See the math section later on.

If you set your program to fix the aspect ratio for you, be sure that “what you see is what you get.” Meaning, check that your project settings for the export match your preview settings while you’re editing. Depending on your program, they may not automatically align. Look into this!

How did your program “fix” the aspect ratio? Did it add letterboxing or resize what you had? If it added letterboxing, did the frame size change? (Did it need to?)

Getting Your Vid in the Right Ratio(for computer viewing)

Setting the right size in Final Cut Pro

Your preview settings and your sequence settings are not necessarily the same. So, how can we make them match? The short answer: bring in clips the size you want your vid to be.

When you import a clip and place it on your timeline for the first time, FCP asks if you want to change your sequence settings to match it. SAY YES. But that only adjusts your preview settings to match your clip (even though FCP did use the word "sequence." Bastards.) You still have to go into your sequence settings and adjust the frame size there to match the size of your clip/source.

To do this, you may need to make a new custom setting by copying a previous one (whatever is close that works for you) and then adjusting the frame size to whatever you like.

When your sequence setting matches your preview setting, and that matches your actual clip size, then hey! What you see will be what you get, and that will be what you want for computer viewing.

*Process borrowed from Laura Shapiro

Part 5: Mixed Aspect Ratios

Finding the Best of Both Worlds

When working with multiple aspect ratios, you have a few choices: 1) Ignore the ratios, meaning at least one source, if not

all, will look “wrong.” (Please don’t choose this? It makes babies cry.)

2) Set one source ratio as your default size and crop the other(s) to match.

3) Find a new, hybrid frame size that maximizes how much of each source’s frame size you can use while cropping both to some extent.

No matter which way you go, your life will be easier if you take letterboxing OUT of the picture first!

Option 2: Working with 2 ratios

When working with Fullscreen and Widescreen sources, or Widescreen and Movie Scope, you can crop one to fit the other.

Decide which aspect ratio / frame size you want your final vid to be. This is now your default source.

The idea is to keep either the height or the width of both sources the same, then crop off the excess width or height of one source.

Be sure your sources are in properly scaled frame sizes (correct aspect ratios) before you start! Otherwise you may not crop correctly.

Option 2: Working with 4:3 and 16:9

You will keep a height of 480 pixels and then trim excess width from the Widescreen source. Resize your Widescreen source to 848 x 480 first.

640 x 480

Fullscreen

Widescreen 848 x 480

There are 208 pixels of width that need to be cut from the Widescreen source. (848 – 640 = 208)

Crop 104 from each side of your Widescreen source, leaving you with a 640 x 480 source that matches your Fullscreen source.

Be aware you will be losing about 25% of your frame! That’s a lot!

To keep a 4:3 Fullscreen vid:

[104 to

cut]

[104 to

cut]

Option 2: Working with 4:3 and 16:9

You will keep a width of 640 pixels and then trim excess height from the Fullscreen source. Resize your Widescreen source to 640 x 368 first.

640 x 368

Widescreen

Fullscreen

640 x 480

There are 112 pixels of height that need to be cut from the Fullscreen source. (480 – 368 = 112)

Crop 66 from the top and bottom of your Fullscreen source, leaving you with a 640 x 368 source that matches your Widescreen source(s).

Be aware you will be losing about 25% of your frame! That’s a lot!

To keep a 16:9 Widescreen vid:

[66 to cut]

[66 to cut]

Option 2: Working with 16:9 and Movies

First, be sure your sources are in properly scaled frame sizes with no letterboxing.

You will keep a width of 720 pixels and then trim excess height from the Widescreen source. Resize your Widescreen source to 720 x 400 and your Movie Scope to 720 x 304 first.

720 x 304

Movie Scope

Widescreen

720 x 400

There are 96 pixels of height that need to be cut from the Widescreen source. (400 – 304 = 96)

Crop 48 from the top and bottom of your Widescreen source, leaving you with a 720 x 304 source that matches your movie source(s).

Be aware you will be losing about 25% of your frame! That’s a lot!

To keep a Movie Scope vid:

[48 to cut]

[48 to cut]

Option 3: Creating a Hybrid File Size

With option 2, only one source is cropped to fit the second source’s file size. With option 3, you crop both sources. Instead of losing a lot of one source, you will only lose a little of both.

To successfully use this method, you must be sure your sources are in correct aspect ratios before cropping, as you will end up with a framesize that does not directly correlate with a 4:3, 16:9, or 2.35:1 ratio. You’re on your own to be sure it looks right! Eep! (Don’t worry, I can help.)

[insert vid here]

Option 3: Working with 4:3 and 16:9

You will be trimming some height off your Fullscreen source and some width off your Widescreen source. This trimming will be less than in option 2.

Resize your Widescreen source to 720 x 400 first and Fullscreen to 640 x 480. You will be keeping the width of the Fullscreen source (640) and the height of the

Widescreen source (400) to create a new hybrid framesize of 640 x 400.

640 x 480 Fullscreen

Widescreen 720 x 400

There are 80 pixels of width that need to be cut from the Widescreen source. (720 – 640 = 80) Crop 40 from left and right.

There are 80 pixels of height that need to be cut from the Fullscreen source. (480 – 400 = 80) Crop 40 from top and bottom , or a combination that adds to 80.

Now you have source that is all 640 x 400. Woohoo!

Your vid size:

640 x 400

Option 3: Working with 16:9 and Movies

You will be trimming some height off your Widescreen source and some width off your movie source. This trimming will be less than in option 2.

Resize your Widescreen source to 848 x 480 first and movie to 928 x 400. You will be keeping the width of the Widescreen source (848) and the height of

the movie source (400) to create a new hybrid framesize of 848 x 400.

848 x 480 Widescreen

Movie Scope 928 x 400

There are 80 pixels of width that need to be cut from the movie source. (928 – 848 = 80) Crop 40 from left and right.

There are 80 pixels of height that need to be cut from the Widescreen source. (480 – 400 = 80) Crop 40 from top and bottom, or a combination that adds to 80.

Now you have source that is all 848 x 400. Woohoo!

Your vid size:

848 x 400

Option 3: Working with 4:3 and Movies

You will be trimming some height off your Fullscreen source and some width off your movie source. It will be a lot, and it will suck.

Resize your Fullscreen source to 640 x 480 first and movie to 928 x 400. You will be keeping the width of the Fullscreen source (640) and the height of the

movie source (400) to create a new hybrid framesize of 640 x 400.

640 x 480 Fullscreen

Movie Scope 928 x 400

There are 288 pixels of width that need to be cut from the movie source. (928 – 640 = 288) Crop 144 from left and right, or a combination that adds to 288. Yep, it’s a lot.

There are 80 pixels of height that need to be cut from the Fullscreen source. (480 – 400 = 80). Crop 40 from left and right.

Now you have source that is all 640 x 400. Woohoo!

Your vid size:

640 x 400

Option 3: Working with all 3 Ratios You will be trimming some height off your Fullscreen source, and some width off

both your movie and widescreen sources. Welcome to the big leagues! Resize your Fullscreen source to 640 x 480, Widescreen to 720 x 400, and

movie to 928 x 400. You will be keeping the width of the Fullscreen source (640) and the height of the

movie source (400) to create a new hybrid framesize of 640 x 400.

Your vid size:

640 x 400

Fullscreen source: Cut 80 pixels of height (480 – 400 = 80) by cropping 40 from top and bottom, each.

Widescreen source: Cut 80 pixels of width (720 – 640 = 80) by cropping 40 from left and right, each.

Movie source: Cut 288 pixels of width (928 – 640 = 288) by cropping 144 from left and right, or any combination that adds to 288.

Now you have source that is all 640 x 400. Woohoo!

Part 6: Exporting for Cons

Getting it right for TV

If you are using a PC, you can run your vids through a program called LlamaEnc, created by AbsoluteDestiny, which will automatically resize them properly and convert them to m2v form for exporting to cons or burning DVDs.

LlamaEnc can be downloaded here: http://www.vividcon.com/llamaenc/LlamaEnc_Setup.exe Note: LlamaEnc is for PC only. To use the program you need to

have the Microsoft .NET Framework 2.0 installed. If you do not have this installed, the LlamaEnc setup will notify you and take you to the download site.

Getting it right for TV Without LlamaEnc, you are on your own for proper

resizing/exporting. This is tricky because you are taking something in square pixels and resizing it to something that will stretch properly when displayed as rectangular pixels. We can create a file that looks right on our computer and resize it so it will look right on a TV.

It comes down to this: Your vid will need to be resized to 720 x 480. But first! You need it to look right on your computer screen. If it’s a 16:9 or movie scope vid, you will need to add letterboxing to increase the size to 720 x 540 first, then resize down to 720 x 480.

So, how do we get your vid into 720 x 540? It depends on what the original aspect ratio is…

What it looks like for 4:3 vids

The original vid is in 4:3 (640 x 480). For a con export in 720 x 480, you simply need to resize your file. Nothing else has changed or been added to the vid. Cons and DVDs love fullscreen!

Original vid:

640 x 480

No letterboxing is needed

What it looks like for 4:3 vids

It will look stretched like this on your computer, but your TV will loooooove it. \o/

Original vid:

640 x 480

resized to

720 x 480

What it looks like for 16:9 vids

This is a screencap of a vid as rendered through LlamaEnc. The original vid is in 16:9 (720 x 400). The con export is 720 x 540, meaning it has 140 pixels of letterboxing added: 70 on top, 70 on bottom. The original vid itself hasn’t been stretched or cropped. Then, resize the vid to 720 x 480 for uploading to cons.

Original vid:

720 x 400

140 pixels of added

letterboxing

Con export vid size: 720 x 540

What it looks like for 16:9 vids

It will look stretched like this on your computer, but your TV will loooooove it. \o/

Original vid:

720 x 540

resized to

720 x 480

What it looks like for Moviescope vids

This is a screencap of a vid rendered through LlamaEnc. The original vid is in 2.35:1 (720 x 304). The con export is 720 x 540, meaning it has 236 pixels of letterboxing added: 118 on top, 118 on bottom. Then, resize it to 720 x 480 for con uploading.

Note: If your movie is already in 16:9 with original letterboxing, use the previous slide.

Original vid:

720 x 304

236 pixels of added

letterboxing

Con export vid size: 720 x 540

What it looks like for Moviescope vids

It will look stretched like this on your computer, but your TV will loooooove it. \o/

Original vid:

720 x 540

resized to

720 x 480

Tips and Tricks

If you’re not sure if the file you have exported is the right size or has the right letterboxing, here are some ideas: With the file open, take a screenshot. Pull the image into

a photo editing program to check the framesize. You can also crop off the letterboxing to make sure your original vid is the right size.

If you have a vid (in the same aspect ratio) that you know has displayed properly at cons, open that m2v file side by side your vid file in question. Are they the same size? Is the letterboxing the same?

Working within your program

The hardest part of exporting for cons is controlling all the variables at work in your program to make sure it is doing what you want!

There is no way this resource could be exhaustive for specific programs. Consult friends and fellow vidders who use the same programs you do for tricks and tips about your specific platform. (Then share your golden wisdom with the rest of us.)

Part 7: Aspect Ratio Math

Using Aspect Ratio Math

Ratios are also division (÷) sentences. Length divided by width = ratio 4:3 4 ÷ 3 = 1.333 16:9 16 ÷ 9 = 1.77 2.35:1 2.35 ÷ 1 = 2.35 For example, a 4:3 source can be 800 by 600 pixels because

800 ÷ 600 = 1.33 If you know the aspect ratio you need and one of your

dimensions, you can figure out what the other side should be. Use any of these: L ÷ W = Ratio; L ÷ Ratio = W; W x Ratio = L Example: I have a 16:9 source that I want to be 600 pixels long.

Length of 600 ÷ Ratio of 1.77 = unknown Width So, 600 ÷ 1.77 = 339 pixels wide

Using Math to Fix Things

If you have a source that looks wrong but you can’t tell how to fix it, you can use math! Decide what the correct ratio should be based on your

knowledge of the source. Take the frame size numbers you are given and divide

the big by the small to see if the answer matches the aspect ratio, or close enough to it (1.33, 1.77, or 2.35)

If it doesn’t, use the formulas on the previous slide to keep either the height or the width you want and adjust the other based on what the aspect ratio should be.

Tip: If you use VLC, you can set different viewing aspect ratios in the “video” menu. Use this to see what your vid/source looks like with different preset ratios. This can help you determine what is right.

Fancy Pants (Sweet Sixteens)

If you want to be really proper, keep your vid dimensions at multiples of 16. This makes your vid very compatible with players, editors, and encoding programs. It’s okay to be a few pixels off the perfect ratio; up to ten pixels won’t make noticeable difference in what your vid looks like. Example: Though 400 x 300 is a perfect 4:3, 300 is not a multiple of 16.

You can use 400 x 304 and you won’t be able to tell the difference.

304 320 336 352 368 384 400 416 432 448

464 480 496 512 528 544 560 576 592 608

624 640 656 672 688 704 720 736 752 768

784 800 816 832 848 864 880 896 912 928

Useful Multiples of 16

*commonly used numbers are bolded

PAR and DAR

You may have seen the terms PAR and DAR before. This can get a bit fancy.

Pixel Aspect Ratio (PAR) refers, mathematically, to the shape of the pixels you are working with. Think: what is the aspect ratio of your pixels? If you are working with square pixels, they are as tall as

they are wide. If we wrote that as a ratio, we would say it’s 1 to 1 (1:1). Remember ratios are also division problems, so 1 ÷ 1 = 1. Therefore, square pixels (on a computer) have a PAR of 1. Rectangular pixels (on a tv) have a PAR of 0.91 because they are not quite square.

DAR

Display Aspect Ratio (DAR) refers, simply, to the aspect ratio of your vid. Think: what is the aspect ratio of your vid when

it displays? Display aspect ratios are 4:3, 16:9, or 2.35:1, as

we have discussed at length.

That wasn’t so scary, was it?

Links and Resources

Damned_colonial’s Guide for converting Mac vids to con format: http://damned-colonial.dreamwidth.org/477307.html *Be sure to read all the comments for additional

information!

Absolute Destiny’s Guide with in-depth explanation of aspect ratio basics: http://www.animemusicvideos.org/guides/avtech/videog

etb2a.html#mozTocId742447 Note: This guide includes PAL numbers! Hooray!