Aspect Ratios/Resolution at DVinfo.net

mdreyes23 · March 16th, 2002, 12:38 AM

This is going to sound like a silly question, but it's late and I'm a little confused on aspect ratios on what I was reading.

When you want to play back DV footage captured and edited back on to a TV with no distortion and no loss of image...do you want to output to tape in square pixels (1.0) or DV NTSC (0.9) format. Footage was captured in 4:3 mode.

Rob Lohman · March 16th, 2002, 09:43 AM

You want 0.9 NTSC pixel aspect. Not square. A TV does not
have square pixels. Only your monitor does.

mdreyes23 · March 17th, 2002, 05:25 PM

Just the answer I was looking for. Thanks Rob.

Then that does bring up another question which I think I have figured out.

Say you want to add regular square pixel video or pictures to your current DV NTSC project and output in DV NTSC format as well. And you don't want those square pixel videos or pictures distorted in any way.

I was reading through this and I think that you have to create those square pixel videos and pictures in a certain resolution so that when you add it to your DV NTSC project (which is non-square pixel), they will not be distorted. Am I right on this?

For example, the text I'm reading right now says that the square pixel video or picture should be in either 640x480 or 720x540 resolution then added to your DV NTSC project. Also, the later resolution is preferable because then you will be downsampling that image and not upsampling which might lose quality.

Does that sound right?

Rob Lohman · March 18th, 2002, 02:02 AM

To answer one thing first. Most of the times it is better to
downsample then up indeed. When not? When you have very
thing lines for example. If you downsample these it will not
look pretty. I have only used two types of external images,
masking pictures (to mask certain sections of a DV stream)
which I did in 1.0 pixel aspect. The other is output from a
3D application called LightWave. Here I can just enter what
the aspect ratio of a pixel is. So there is no need for me
to work with other resolutions....

I'm afraid I really can't help you much with this issue. I suggest
some trial and error and calculate the difference you need.
It is only math afterall.

Good luck!

March 16th, 2002, 12:38 AM	#1
mdreyes23 Registration Incomplete -- contact Admin. Join Date: Feb 2002 Location: Virginia Posts: 108	Aspect Ratios/Resolution This is going to sound like a silly question, but it's late and I'm a little confused on aspect ratios on what I was reading. When you want to play back DV footage captured and edited back on to a TV with no distortion and no loss of image...do you want to output to tape in square pixels (1.0) or DV NTSC (0.9) format. Footage was captured in 4:3 mode.

March 16th, 2002, 09:43 AM	#2
Rob Lohman RED Code Chef Join Date: Oct 2001 Location: Holland Posts: 12,514	You want 0.9 NTSC pixel aspect. Not square. A TV does not have square pixels. Only your monitor does. __________________ Rob Lohman, visuar@iname.com DV Info Wrangler & RED Code Chef Join the DV Challenge \| Lady X Search DVinfo.net for quick answers \| Buy from the best: DVinfo.net sponsors

March 18th, 2002, 02:02 AM	#4
Rob Lohman RED Code Chef Join Date: Oct 2001 Location: Holland Posts: 12,514	To answer one thing first. Most of the times it is better to downsample then up indeed. When not? When you have very thing lines for example. If you downsample these it will not look pretty. I have only used two types of external images, masking pictures (to mask certain sections of a DV stream) which I did in 1.0 pixel aspect. The other is output from a 3D application called LightWave. Here I can just enter what the aspect ratio of a pixel is. So there is no need for me to work with other resolutions.... I'm afraid I really can't help you much with this issue. I suggest some trial and error and calculate the difference you need. It is only math afterall. Good luck! __________________ Rob Lohman, visuar@iname.com DV Info Wrangler & RED Code Chef Join the DV Challenge \| Lady X Search DVinfo.net for quick answers \| Buy from the best: DVinfo.net sponsors

March 17th, 2002, 05:25 PM	#3
mdreyes23 Registration Incomplete -- contact Admin. Join Date: Feb 2002 Location: Virginia Posts: 108	Just the answer I was looking for. Thanks Rob. Then that does bring up another question which I think I have figured out. Say you want to add regular square pixel video or pictures to your current DV NTSC project and output in DV NTSC format as well. And you don't want those square pixel videos or pictures distorted in any way. I was reading through this and I think that you have to create those square pixel videos and pictures in a certain resolution so that when you add it to your DV NTSC project (which is non-square pixel), they will not be distorted. Am I right on this? For example, the text I'm reading right now says that the square pixel video or picture should be in either 640x480 or 720x540 resolution then added to your DV NTSC project. Also, the later resolution is preferable because then you will be downsampling that image and not upsampling which might lose quality. Does that sound right?