Ratios Computer/NTSC/PAL

The pixels ratios are differents between P.C. and TV:

So a vidéo 16:9 est really displayed 16:9 in scale

else the picture 640x360 is vertically expansed +9% in NTSC and compressed -10% in PAL

It is exactly i can see on my TV.

Note than on my TV 16:9. the dimension is too little, i have to zoom, i didn't have this problem with my old 4:3 tv.

DVD

	DVD encoding is anomorphique. 720x576 (for PAL1.25) ou 720x480 (for NTSC 1.5) but it is diffused in 1.85:1 (16:9)
	panoramic (1.85:1), scope (2.35:1), animation (1.65:1)

so the DVD reader compress vertically to display it on TV:

	1.85/1.25 *10/11 = 1.35 in PAL et
	1.85/1.5 * 59/54 = 1.35 in NTSC

Same work for the two standard!

I try it on the kiss and it has no difficulty even to display a PAL DVD in a NTSC TV. So the kiss is able to apply a corection of 1.35 +-10%

My TV zoom is inactive in this mode!

A 16:9 TV has differents zoom modes :

	Z0: good for the TV, you have a 4:3 picture with black band on the sides
	Z1: good for TV movies, you are in true 16:9
	Z3 : Cinérama, you are in 16:9 from a 4:3 picture so you have deformation.

I use for this analysis a circle video 16:9 that i measure. I am in PAL std

	Z0 :My picture is little the ratio error is 10% (vertically compressed)
	Z1 : I am full screen but the ratio error is 20% !!!!.

The zoom 1 increase the compression by 10 %.

When i select on the kiss the NTSC output the zoom compression of 10% correct the NTSC dilatation of 10% and my circle is perfect

So it was why i haven't any deformation in NTSC !

There is still some troubles:

	a 720x format is tronqued in top and bottom but there is few divx in this format
	a 4:3 format is very tronqued, generally i use the cinerama mode with a bad ratio of 10% and there is few 4:3 divx

It is why i found the ratio error not acceptable (20%) and corrected in NTSC and other user find it acceptable (10%) and not corrected in NTSC !

Here is my test video mire 640x360