confused about aspect ratios

[Vaughn]

Well i thought i new enough about aspect ratios to make my own DVD rips but obviously i do not.

Since i watch my rips on a standard square NTSC TV i have always cropped the black bars out of my source material which is usually 16:9 NTSC. However i always thought to myself that when i have enough $ i will buy a widescreen TV and using a program like Bsp player with 16:9 aspect ratio turned on instead of the usual 4:3 i would enjoy the movies they way they were meant to be displayed.

How stupid am i. When i actually did some tests using Bsp player i realized that this 4:3, 16:9 playback function has nothing to do with displaying the correct aspect ratio, all it does is remove/add black bars. For example if i open a rip where the source material was 16:9 but i cropped it to 4:3 while encoding and then play it back 16:9 via Bsp the black bars appear allright (even though they are smaller than the original black bars) but the movie is by no means 16:9, it is still 4:3 just with black bars and a small screen!

Is there no way to display a movie in it's correct 16:9 aspect ratio using some sort of a playback device after it has been cropped to 4:3?

[khp]

Re: confused about aspect ratios

Originally posted by Vaughn

Is there no way to display a movie in it's correct 16:9 aspect ratio using some sort of a playback device after it has been cropped to 4:3?

Ehh, if you have cropped the frame to 4:3, then it's a 4:3 movie, in which case it makes no sense to display it as 16:9. On the other hand if you need to stretch the image to fit a specific aspect ratio, just use Zoom Player.

Note that most 16:9 TVs have a ton of options for displaying the image at different AR's, so assuming that you have encoded the movies at the proper aspect ratio in the first place. You shoud be able to play it at the proper aspectratio, without adding black bars on all four sides.

Personally I use a Matrox Marvel G450eTV, which knows that my TV is a 16:9 set, so the graphics card will squeese any normal avi horizontally by a factor of 16:9/4:3, and send that to the TV, which will stretch the picture back from 4:3 to 16:9.

[Vaughn]

Okay i have checked out Zoom player and i am impressed by the options for different aspect ratio's that it contains. I am however still puzzled by the following:

If a player like zoom can resize to any aspect ratio you like during playback then what is the purpose of cropping the source material when encoding? Is "stretching" the video during playback the same as cropping during encoding?

[setarip]

"what is the purpose of cropping the source material when encoding?"

Only to reduce filesize.

By the way, good ol' Windows Media Player v.6.4 will playback such cropped videos properly - automatically...

[Vaughn]

Do i understand you correctly that the black bars actualy take up MORE file size than video? If so then....

In theory lets say for my end result i want to maintain the 16:9 aspect ratio that is presented with my original source material. So if black bars take up more room than video why don't i crop them to 4:3 during encoding and then later during playback stretch it back to 16:9 in a player like zoom? Would i not have a higher quality video then since it would be more compressable without the black bars during encoding which means higher bitrate = better video?

[toastem]

The black bars in a 16:9 do take up space, it really isn't much (say @ 1500kbps). And cropping to a 4:3 will either chop the sides of the video (the whole point of widescreen!), distort the image, or a combo of the two; and then you want to strech it back to a 16:9, futher distroting the video! To keep the 16:9 you can crop out the black bars (say 720x320) or encode it as is (ex- 720x480). Either way will end up in a 16:9 and both will be very good quality ( using bitrates of 1200kbps+ IMO). if you need a smaller file size, reduce the enitre image by 3/4 or 1/2 of the origonal size.(ex: 720x480 = 540x360)

[setarip]

Cropping the black bars off a 16:9 video does not result in a 4:3 video. It results in a 16:9 video with the black bars cropped off.

As I mentioned before, good ol' Windows Media Player v.6.4 will playback such cropped videos properly - automatically...