Why does my exported quicktime movie of 24pa anamorphic 16:9 footage look stretched horizontally compared to the aspect ratio of the same footage in the canvas of FCP? Does anybody notice this difference?

Yeah just a quirk with quicktime not seeing the anamorphic flag. If you are sending the movie over to DVD SP it will properly scale it, if you want to go to the web you have to export it a custom size equal to the 16:9 ratio.

Thanks for the info Nate. I'm thinking when you wrote "scale", you meant it'll be corrected?

Nevermind the last post. duh.

Why does my exported quicktime movie of 24pa anamorphic 16:9 footage look stretched horizontally

Actually I think you meant that it looks stretched vertically, right? Everyone looks tall and skinny (some of us might not mind that ;-)

Quicktime doesn't do any scaling to correct the aspect ratio, it just shows all the pixels. In fact, regular 4:3 footage is wrong also. The pixels on a computer monitor are square, so when Quicktime displays them you have a 720x480 image. If you want properly scaled 4:3 footage you need to change the size to 640x480 or 854x480 for 16:9.

Amos:

What kind of camera did you shoot with? The reason I ask is because some cameras have different pixel shapes and sizes. So, you cannot assume that you are shooting in 4:3 or 16:9. Here's an example:

I own a Sony HVR-Z1U. At first, I had a similar problem with my QT encodes. As Boyd properly states, they looked vertically stretched. After a day's worth of investigating and experimenting, I found the reason.

The Z1U does not shoot in 16 x 9 anamorphic mode. Instead, it is a true 16:9 HDV format. At first, this did not make sense. As you may know, High-Definition video cameras (HD) use a 1920 x 1080 image resolution which, when you divide one into the other, equates to a ratio of 16:9. The Sony Z1U HDV camera uses a different High-Definition image resolution of 1440 x 1080. When you divide one into the other you get a ratio of 4:3.

However, not all pixels are created equally. There is not a standard pixel size or shape. The high-end HD cameras use square pixels, so the 1920 x 1080 square pixels does indeed produce an aspect ratio of 16:9. The HDV format uses rectangular shaped pixels so even though there are only 1440 of them across, the resultant aspect ratio is still a true 16:9 ratio and not the 4:3 ratio one would expect by using simple math. Each pixel on Sony's HDV CCDs is 1.33 to 1 (length to width).

I had encoded my QT files as 4:3 at first--thinking that 1440x1080 was a 4:3 ratio. That looked strange, so then I encoded the QT file as an 16:9 anamorphic--that looked better but was still not right. Once I realized that the HDV format is a true 16:9, not an anamorphic, I then set a custom image size to proper, true 16:9 dimensions and have been encoded great looking QT files since.

Pixels are not a unit of measurement anymore than a house is a unit of measurement. They come in different shapes and sizes. Most people do not realize this.

I hope this helps.

hd100u, horizontally stretched...wider than normal

hd100u, horizontally stretched...wider than normal

Well, the JVC HD100 is an HDV camera. Therefore, in HD mode, it is true 16:9, not anamorphic. In fact, your camera has square pixels on its CCDs so the 1280 x 720 pixel count does indeed equal a true 16:9 ration.

So, if you have the anamorphic flag set, it could cause issues. If I recall correctly, when I first tried encoding my Z1U footage with the anamorphic flag set, I think it looked somewhat horizontally stretched.

Try removing the anamorphic flag and encode as a true 16:9.

Now, if you shot in 16:9 DV mode instead of HDV, then the captured footage would be anamorphic. The data would be recorded at 720 x 480, a ratio of 3:2.

What are the pixel dimensions of the original footage, and what are the pixel dimensions of the exported Quicktime file?

You know, I just realized that this forum is for NLE DV editing discussions. So, I guess that answers my own question that I posed to Amos. He must have shot in DV mode.

Please disregard my HDV true 16:9 versus DV 16:9 anamorphic comments.

I'm going to bed to catch up on sleep.

Quicktime doesn't do any scaling to correct the aspect ratio, it just shows all the pixels. In fact, regular 4:3 footage is wrong also. The pixels on a computer monitor are square, so when Quicktime displays them you have a 720x480 image. If you want properly scaled 4:3 footage you need to change the size to 640x480 or 854x480 for 16:9.

Boyd, I've noticed that the recent QT updates have fixed it's ability to playback 16:9 DV footage. I recently opened up a clip in QT player that was captured in FCP with the DV Anamorphic easey setup and it played back in the proper 16:9 aspect ratio.

I have always been annoyed with this seemingly overlooked issue with QT but now it seems to have been addressed.

Really? I have QT 7.0.3 and I just tried opening some anamorphic DV clips from a project. They just appear as 720x480 with square pixels on my monitor. Maybe there's a newer version that fixes this?

Really? I have QT 7.0.3 and I just tried opening some anamorphic DV clips from a project. They just appear as 720x480 with square pixels on my monitor. Maybe there's a newer version that fixes this?

Boyd:

You are three versions behind. Currently, QT is at 7.1.2. Before that, there was 7.1.1, and before that 7.0.4.

Heh... story of my life! ;-) However, after getting burned with QT updates before in FCP I've learned to take my time catching up with the latest version, especially when I don't have the latest version of FCP!

BTW, I see that you're using Vue 5 infinite. I didn't know we had any other users of that software around here. It's a terrific package, although a little buggy (but I'm also a few versions behind there too, for similar reasons ;-)

You might want to participate in this thread, or some of the others in the links I posted there:http://www.dvinfo.net/conf/showthread.php?t=66384

I understand completely the desire to wait and see with QT updates. I've had a few issues myself in the past--that is, with QT!

Vue 5 Infinite is a lot more stable than the earlier versions. Of course, E-Onsoftware just yesterday announced Vue 6 Infinite. I'll wait awhile to upgrade but it does sound like a significant update. http://www.e-onsoftware.com/products/vue6/

Thanks for the forum link to the 3D package thread. I'll post something later.

thanks guys. I need to download the new QT. And Jeff, I"m shooting on DV for now... I"ll try removing the anamorphic setting and going 16:9. I always thought anamorphic was 16:9... what's the difference?

wait, FCP 4.5 groups 16:9 and anamorphic as the same thing... I'm confused.

For DV, anamorphic and 16:9 are the same thing. All DV is 720x480 (NTSC) pixels. The only difference for 16:9 is that the pixels are displayed wider. Anamorphic roughly translated from Greek means "changed form."

So on FCP 4.5 (or the newer versions) the only way to identify your footage as 16:9 is to click the "anamorphic" checkbox in the clip and sequence properties. That tells FCP to stretch the image wider while you edit, and it embeds a signal in the video stream which some devices (monitors, decks and some software) can recognize and cause them to go into 16:9 mode.

so, outside of dv, what is the difference between anamorphic and 16:9? Sometimes I hear 2.35:1 referred to as anamorphic.

Here are two links that may help:

http://gregl.net/videophile/anamorphic.htm

http://www.kenstone.net/fcp_homepage/understanding_16_9.html

Sometimes I hear 2.35:1 referred to as anamorphic.

Yes - see my definition of anamorphic above. It describes a process where you fit a rectangular peg in a square hole :-) During the 1950's when everyone was excited about widescreen movies someone came up with the idea of using a special lens to squash everything in the horizontal dimension and record it on film. Then in the theatre another lens was used on the projector to stretch the film image to the full width of the screen.

With DV the same thing is being done digitally by dividing/multiplying the horizontal position of the pixels. So anamorphic could apply to any process that accomplishes the same thing.