iMovie Problems (Image size etc.)

Please see this link for a detailed description the problem.

http://www3.telus.net/~jessum/PAGES/imoviequestion01.html

Dual G4 Tower Mac OS X (10.3.8)

Posted on Apr 6, 2006 7:57 PM

Reply
15 replies

Apr 6, 2006 11:28 PM in response to Paint Guy

Hi PG,

best posting of a Question so far ever!!! really, EXCELLENT!

inhope,it answers some of your Qs, have a read here (follow in article included links)
http://danslagle.com/mac/iMovie/video/2002.shtml

from me just some basic answers:
* iM uses a compressor, dv, AND the final project has a res of 640x480/72dpi (NTSC)... that is a 1/6th... a fraction of your raw material...
* a computer uses some very different technique for displaying then a TV
* you can tell KenBurns (not personally...), where to start/end.. see your settings in iM
* I'm not good in html-coding, but reading the source of your website ... < embed height="270" pluginspage="http://www.apple.com/quicktime/download/" src="../MOVIES/objects.mov" type="video/quicktime" width="480" controller="false" autoplay="true" > ... shouldn't be "controller" set to "true" to see the.. ehm, controller... ;-))

hope, that helps....

Apr 7, 2006 1:33 AM in response to Paint Guy

One basic error in your example is that the graphics you are importing uses square pixels and iMovie 5-6 automatically (and very much correctly) convert it to rectangular pixels. That's where it MUST add black borders to some images.

Other thing to remember is that the sampling matrix of the DV area is NOT the active image area -- the latter describes the real aspect ratio after you remember to think in rectangular pixels!!

Does your head hurt yet? This page describes the whole mess very pedantically:

http://www.iki.fi/znark/video/conversion/

See also:

http://www.sjoki.uta.fi/~shmhav/iMovieHD_6bugs.html#stills

Apr 7, 2006 10:23 AM in response to Paint Guy

When I used the "Ken Burns" effect it moved the image up so when the movie
plays a black bar appears. Why is this? Why doesn't it just zoom in from the
originally positioned image?


By default, Ken Burns centers the image so a black border, if there is one, is equidistant on opposing sides.

But Ken Burns lets us control the start/end position of a clip, which lets us add a pan to the image as well as a zoom. (To add a zoom, drag the Zoom slider. To add a pan, drag the Preview window.) My guess is you've moved the start/end pan positions recently, either intentionally or accidentally.

To re-center the start/end positions, turn ON the Ken Burns checkbox. Stop the preview. Click on the Start side of the Start/End thingy. Drag the Zoom slider—the top slider—a bit to the right, then all the way to the left. Repeat for the End side. Import the image. New imports should now work as you want. (You may need to re-import previously-imported images, or at at least Update them.)

To avoid the black bars in iMovie 5/6, you always need to zoom in a bit, or crop the image with other software. More about that here:
http://discussions.apple.com/click.jspa?searchID=-1&messageID=961045

Karl

Apr 7, 2006 8:24 PM in response to Karl Petersen

Here's a chart of suggested image settings, updated for iMovie 6/iPhoto 6.

SUGGESTED IMPORT SETTINGS FOR 4:3 IMAGES — iMOVIE 6

To prevent pillarboxing of an imported image — where iMovie adds a black border along two edges — do one of these:
1) Set the Ken Burns Zoom to enlarge the image a bit as it is imported. The suggested zoom for each type of iMovie project is below.
2) Use iPhoto 6 to crop the image before importing to iMovie, then import with a Ken Burns zoom of 1.00.

(This table is best viewed with monospace font, e.g. Courier or Monaco)

------------------------------------------------------------------------
NTSC PROJECTS (29.97 fps, North America, Japan)
iMovie HD 6, iPhoto 6
------------------------------------------------------------------------

iMOVIE FRAME SIZE (pixels)
MPEG-4: 640 x 480
Standard DV: 720 x 528
DV Widescreen: 869 x 480
HDV 720p: 1280 x 720
HDV 1080i: 1440 x 1080

MINIMUM IMAGE SIZE (pixels).
Double these sizes for 2x Ken Burns zoom, triple for 3x Ken Burns zoom, etc.
MPEG-4: 640 x 480
Standard DV: 720 x 528
DV Widescreen: 874 x 480
HDV 720p: 1280 x 720
HDV 1081: 1920 x 1080

SUGGESTED KEN BURNS ZOOM TO AVOID BLACK BORDERS
MPEG-4: 1.00
Standard DV: 1.03
DV Widescreen: 1.37
HDV 720p: 1.33
HDV 1080i: 1.33

SUGGESTED iPHOTO CROP TO AVOID BLACK BORDERS
Import cropped image to iMovie with Ken Burns zoom of 1.0
MPEG-4: 4:3
Standard DV: 1.364:1
DV Widescreen: 1.818:1
HDV 720p: 16:9
HDV 1080i 16:9

------------------------------------------------------------------------
PAL-Format PROJECTS (25 fps, Europe)
iMovie HD 6, iPhoto 6
------------------------------------------------------------------------

iMOVIE FRAME SIZE (pixels)
MPEG-4: 640 x 480
Standard DV: 784 x 576
DV Widescreen: 1040 x 576
HDV 720p: 1280 x 720
HDV 1080i: 1440 x 1080

MINIMUM IMAGE SIZE (pixels).
Double these sizes for 2x Ken Burns zoom, triple for 3x Ken Burns zoom, etc.
MPEG-4: 640 x 480
Standard DV: 788 x 576
DV Widescreen: 1050 x 576
HDV 720p: 1280 x 720
HDV 1080i: 1920 x 1080

SUGGESTED KEN BURNS ZOOM TO AVOID BLACK BORDERS
MPEG-4: 1.00
Standard DV: 1.03
DV Widescreen: 1.37
HDV 720p: 1.33
HDV 1080i: 1.33

SUGGESTED iPHOTO CROP TO AVOID BLACK BORDERS
Import cropped image to iMovie with Ken Burns zoom of 1.0
MPEG-4: 4:3
Standard DV: 1.364:1
DV Widescreen: 1.822:1
HDV 720p: 16:9
HDV 1080i: 16:9

Karl

Apr 7, 2006 11:51 PM in response to Paint Guy

Thank you all for your help thus far. I have spent all day on this and I still am confused about some things. Please see the link below.

I have written out my procedure to create the correct image size to use in an imovie. I really don't know why this has to be so complicated though.

Please read my steps and tell me if I am doing this right and if there is a better way etc.

I understand everything up to Step #5 this is where I am lost. Please explain this to me!

http://www3.telus.net/~jessum/PAGES/imoviequestion02.html

Apr 8, 2006 12:56 AM in response to Paint Guy

I'm bad in math.. but I start stumbling even at step 2:

(I want my final size to be: 480 x 270)

sorry to say, but what YOU want is irrelevant; see Karl's excellent chart, iM "wants" dv, as NTSC/PAL and in two flavors, HiDef (=that is NOT a criteria for you, it means a video-standard!) and "normal"...

so, Canada is NTSC= 720 x 528, that's all.
no further options.
and esp. no "exotic" aspect ratios as 1:1.777 as yours.... 😉

And to avoid black-bars, follow Matti's advice about square/non-square pixels....

in case, your animations HAVE such a extreme "widescreen" appeal, you HAVE to add black borders....

Boom! done.

😉

Apr 8, 2006 1:58 AM in response to Paint Guy

Your "question02" seems to be OK. I would have done the calculations via a different route, though. But the end result is similar:

Your calculations seem to use PAL so I use PAL in my example:

PAL DV sampling matrix is 720x576, but PAL actual active picture size is 702x576, and the pixel aspect ratio for both is 128:117 = ~1.094.

http://www.iki.fi/znark/video/conversion/

Now, when those 702 and 720 horizontal square pixel rows are scaled to rectangular pixel rows on a TV, they are multiplied by the pixel aspect ratio 128:117 which gives us 768 for the actual active picture width and and ~788 for the sampling matrix width (the height remains the same).

Notice that 768:576 = 4:3 -- THAT is the 4:3 ratio on a TV! On the other hand the 788x576 square pixel sampling matrix figure includes 10+10 pixels on the left+right that can consist of black pixels. The pixels are black if the source is analog. But if the source is DV, then there usually is real material on the sides, too.

If the imported square pixel image's ratio is 788x576 (or any other similar ratio), THEN iMovie won't add black borders to it because it fits exactly to the 720x576 rectangular pixel sampling matrix. Usually it is best to use some larger multiple of those figures like 1024x749, 2048x1497, 2101x1536 etc so iMovie can better downscale the imported image (sometimes iMovie does this suboptimally thus rendering the images TOO sharp which causes flickering on an interlaced TV but I won't now go into that).

With 16:9, the ratio is (16:9):(4:3) = 4:3 larger than with 4:3. Multiply 702 and 720 with 4:3 and with the pixel aspect ratio 128:117 so you get the corresponding square pixels 1024 and ~1050. Notice that 1024:576 = 16:9 -- THAT is the 16:9 ratio on a TV!

Also then the 1050x576 sampling matrix includes extra material on the left+right that should NOT be included in the 16:9 aspect ratio calculations (a common mistake!). If the imported images' ratio is 1050x576, THEN iMovie won't add black borders to them because it fits exactly to the 720x576 rectangular pixel sampling matrix.

With NTSC the calculations are the same although some figures look weird: NTSC DV sampling matrix is 720x480, but NTSC actual active picture size is 710.85x486 (weird but true!), and the pixel aspect ratio is 4320:4739 = ~0.912.

So the square pixel NTSC actual active picture size is 648x486. 648:486 = 4:3 -- as weird as it may sound THAT is the 4:3 ratio on a TV!

Square pixel NTSC sampling matrix is 656x480. If the imported image's ratio is 656x480, then iMovie won't add black borders to it. ...but usually it is better to use an image that haven't to be upsampled in any direction so a similar ratio like like 720x527, 1024x751, 2048x1502, 2095x1536 etc can be used instead (BTW, iMovie HD 5-6 save still images as 720x528, which is a nice "coincidence").

With 16:9 the square pixel NTSC the actual active picture size is 864x486. 864:486 = 16:9 -- as weird as it may sound THAT is the 16:9 ratio on a TV!

With 16:9 the square pixel NTSC the sampling matrix is ~875x480. If the imported images' ratio is 875x480, then iMovie won't add black borders to it.

Now, didn't all that make sense! 😉

Apr 8, 2006 2:01 PM in response to Matti Haveri

Matti Haveri, you said:

Also then the 1050x576 sampling matrix includes extra material on the left+right that should NOT be included in the 16:9 aspect ratio calculations (a common mistake!). If the imported images' ratio is 1050x576, THEN iMovie won't add black borders to them because it fits exactly to the 720x576 rectangular pixel sampling matrix.

Sorry but all this is way too complicated for me. I am going to try and render an image at 1050 x 576, then import that picture into iMovie and then export my QT Movie at 480 x 270. This should be a 16:9 aspect ratio and hopefully will work.

Apr 9, 2006 12:51 AM in response to Paint Guy

Sorry but all this is way too complicated for me


Just forget the calculations and remember that 1050x576 still image excatly fits to the 16:9 video frame. Or use some other ratio and accept that there will be some black borders.

OK, if you want to export rectangular pixel 16:9 720x576 PAL DV to square pixel 480x270 AND preserve the correct aspect ratio, you should:

http://www.iki.fi/znark/video/conversion/

1. Resample the image to 492x270. Oh, and if the material is interlaced, do deinterlace it in this step because otherwise you get nasty artifacts because vertical resolution is scaled.

2. Optionally, then crop 6+6 pixels from the left+right to get 480x270.

BTW, why did you pick just 480x270 as the desired output? Why not use some even multiple of the vertical input resolution such as 512x288 etc? That might scale better.

Also: why do you import the images to iMovie, THEN export them? Using QT Player to export the original square pixel image sequences straight to square pixel 480x288 movie might save you from the rectangular pixel headaches and multiple scalings. Or do you want to edit the material in iMovie?

Apr 10, 2006 8:46 AM in response to Matti Haveri

Sorry but all this is way too complicated for me


1. Just forget the calculations and remember that
1050x576 still image excatly fits to the 16:9 video
frame. Or use some other ratio and accept that there
will be some black borders.

2. OK, if you want to export rectangular pixel 16:9
720x576 PAL DV to square pixel 480x270 AND preserve
the correct aspect ratio, you should:

http://www.iki.fi/znark/video/conversion/

3. Resample the image to 492x270. Oh, and if the
material is interlaced, do deinterlace it in this
step because otherwise you get nasty artifacts
because vertical resolution is scaled.

4. Optionally, then crop 6+6 pixels from the
left+right to get 480x270.

5. BTW, why did you pick just 480x270 as the desired
output? Why not use some even multiple of the
vertical input resolution such as 512x288 etc? That
might scale better.

6. Also: why do you import the images to iMovie, THEN
export them? Using QT Player to export the original
square pixel image sequences straight to square pixel
480x288 movie might save you from the rectangular
pixel headaches and multiple scalings. Or do you want
to edit the material in iMovie?


Q1. Does Finall Cut Express or Final Cut Pro add these annoying black borders? Do either one of them make it easier to bring in images?

Q2, Q3 & Q4. Thanks, am I adding 12 pixels to the image when I render it, then when iMovie imports it it will shrink the vertical height so there are no black borders. This seams easier. Can I then choose any 16:9 ratio like 1440 x 810 then just add 12 pixels to the vertical height so it's 1440 x 822 then imovie will import it correctly? or does the 12 pixels change depending on the size of the image?

Q5. I had a friend use this size and I thought it was a correct calculation of 16:9 because 16 x 30 =480 and 9 x 30 = 270. Isn't this right?

Q6. I use iMovie because I wanted to buy an affordable editing application. I guess iMovie is only for importing video and not still images. Is this correct? Also going from square to square in QT won't work for movies on Television.

Just trying to understand all this.



Dual G4 Tower Mac OS X (10.3.8)

Dual G4 Tower Mac OS X (10.3.8)

Apr 10, 2006 9:35 AM in response to Paint Guy

Paint Guy, I suspect you may be making this WAY more complicate than it needs to be.

As Matti said:
Just forget the calculations and remember that 1050x576 still image excatly
fits to the 16:9 video frame.


Try following these steps:

1. Save your image so it has the aspect ratio it has now, but is a bit larger than 1050x576.
2. Crop the image to 1050x576.
3. Import the cropped image to iMovie.

Karl

Apr 10, 2006 12:02 PM in response to Paint Guy

For example: I have a 2048x1536 still image from a digital camera that I want to import to 16:9 iMovie project with no black borders.

I do remember that the ratio has to be 1050:576 for 16:9 PAL.

a) The easiest way is to scale the image to 1050 width while preserving the aspect ratio in the image editing app: the app automatically scales it to 1050x788. The next step is to crop it to 1050x576. Voila: iMovie happily imports it with no black borders.

b) If I want the greatest possible resolution with the same ratio, the height has to be 2048:(1050:576) = 1119. So I just crop the image to 2048x1119 and iMovie is even happier because it has more pixels to chew and I avoided one scaling step!

Apr 10, 2006 12:38 PM in response to Matti Haveri

For example: I have a 2048x1536 still image from a
digital camera that I want to import to 16:9 iMovie
project with no black borders.

I do remember that the ratio has to be 1050:576 for
16:9 PAL.

a) The easiest way is to scale the image to 1050
width while preserving the aspect ratio in the image
editing app: the app automatically scales it to
1050x788. The next step is to crop it to 1050x576.
Voila: iMovie happily imports it with no black
borders.

b) If I want the greatest possible resolution with
the same ratio, the height has to be 2048:(1050:576)
= 1119. So I just crop the image to 2048x1119 and
iMovie is even happier because it has more pixels to
chew and I avoided one scaling step!


Matti,

Ok, in Photoshop I created an image 1050 x 576. I then scaled the image proportionately to 2048 and the height was 1123. So the image would be 2048 x 1123. How did you get 2048 x1119?



Dual G4 Tower Mac OS X (10.3.8)

This thread has been closed by the system or the community team. You may vote for any posts you find helpful, or search the Community for additional answers.

iMovie Problems (Image size etc.)

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.