help with compression and keeping widescreen aspect. at DVinfo.net

Jeri Trinidad · April 10th, 2005, 05:52 PM

so I have a panasonic pv-gs150, I took some clips in the widescreen mode and transferred them to my computer, the computer plays them in 720x480, and is displayed in a 16:9 aspect ratio, so I tried to convert the video with divx to 872x480, it converts fine but when I match up both files, the compressed one is a bit wider. So how do I compress the original video to 720x480 with an 16:9 AR?

In a nutshell, how do I get my videos to look like this?

http://www.fortvir.net/p3u/GS150_park.mpg

Rob Lohman · April 11th, 2005, 03:30 AM

The trick is two-fold. Write down the pixel aspect ratio your NLE
is set to when you are in the 16:9 project. Multiply this number
by 720. You probably already did this since you are exporting at
872x480.

Then MAKE SURE that in your export settings the PIXEL aspect
ratio is set to 1.0!!!!

That last part should do the trick.

Jeri Trinidad · April 11th, 2005, 12:01 PM

Could you explain that step by step? This is my first camcorder Ive ever had and this all is pretty new to me...

sorry

And Im not exporting at 872x480, thats just the resolution Im compressing at, the source file is still 720x480 displayed at 16:9

Kelvin Kelm · April 11th, 2005, 02:09 PM

For both 4:3 and 16:9, the DV format (and the DVD standard) uses 720 x 480 pixels (which translates to 3:2). In order for the video to display correctly, the pixels in DV are either squeezed (by approx 0.9 for 4:3) or stretched (approx 1.21 for 16:9).

When compressing to another format that uses square pixels (1.0), you need to adjust the pixel aspect ratio accordingly. To maintain 480 horizontal lines use 854 x 480 for 16:9 and use 640 x 480 for 4:3.

Hope this helps.

Jeri Trinidad · April 11th, 2005, 02:15 PM

Well what codec supports that resolution? I just tried putting that in for divx and it doesnt work.

Jeri Trinidad · April 11th, 2005, 02:45 PM

Or how do I get my video to look like the link below, where its still 720x480, but displayed as 16:9? Just like my original files.

http://www.fortvir.net/p3u/GS150_park.mpg

April 10th, 2005, 05:52 PM	#1
Jeri Trinidad Tourist Join Date: Apr 2005 Posts: 4	help with compression and keeping widescreen aspect. so I have a panasonic pv-gs150, I took some clips in the widescreen mode and transferred them to my computer, the computer plays them in 720x480, and is displayed in a 16:9 aspect ratio, so I tried to convert the video with divx to 872x480, it converts fine but when I match up both files, the compressed one is a bit wider. So how do I compress the original video to 720x480 with an 16:9 AR? In a nutshell, how do I get my videos to look like this? http://www.fortvir.net/p3u/GS150_park.mpg

April 11th, 2005, 03:30 AM	#2
Rob Lohman RED Code Chef Join Date: Oct 2001 Location: Holland Posts: 12,514	The trick is two-fold. Write down the pixel aspect ratio your NLE is set to when you are in the 16:9 project. Multiply this number by 720. You probably already did this since you are exporting at 872x480. Then MAKE SURE that in your export settings the PIXEL aspect ratio is set to 1.0!!!! That last part should do the trick. __________________ 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

April 11th, 2005, 12:01 PM	#3
Jeri Trinidad Tourist Join Date: Apr 2005 Posts: 4	Could you explain that step by step? This is my first camcorder Ive ever had and this all is pretty new to me... sorry And Im not exporting at 872x480, thats just the resolution Im compressing at, the source file is still 720x480 displayed at 16:9

April 11th, 2005, 02:09 PM	#4
Kelvin Kelm Regular Crew Join Date: Oct 2003 Location: Katy, Texas Posts: 49	For both 4:3 and 16:9, the DV format (and the DVD standard) uses 720 x 480 pixels (which translates to 3:2). In order for the video to display correctly, the pixels in DV are either squeezed (by approx 0.9 for 4:3) or stretched (approx 1.21 for 16:9). When compressing to another format that uses square pixels (1.0), you need to adjust the pixel aspect ratio accordingly. To maintain 480 horizontal lines use 854 x 480 for 16:9 and use 640 x 480 for 4:3. Hope this helps.

April 11th, 2005, 02:15 PM	#5
Jeri Trinidad Tourist Join Date: Apr 2005 Posts: 4	Well what codec supports that resolution? I just tried putting that in for divx and it doesnt work.

April 11th, 2005, 02:45 PM	#6
Jeri Trinidad Tourist Join Date: Apr 2005 Posts: 4	Or how do I get my video to look like the link below, where its still 720x480, but displayed as 16:9? Just like my original files. http://www.fortvir.net/p3u/GS150_park.mpg