Doom9's Forum - View Single Post - YUY2 Captured Resolution Not Divisible By 4, Won't Open In VDub...Help!!!

trevlac · 5th December 2003, 05:49

Analog is not natively RGB. I believe PAL is close to YUV and NTSC is like YUV but YQI. A BT878 will create pixels in packed YCrCb 4:2:2 format. From here it converts to many formats such as YUY2, YUV12, and RGB. I think YCrCb is basically the same as YUY2.

So basically, I guess one should ask a BT878 for YUY2 not RGB, if you use huffy.

For Packed 4:2:2 fromats like YUY2, each macropixel is 4 bytes (16 bits per pixel) and contains 2 pixels. The byte order is Y0 U0 Y1 V0 where U and V are shared by pixel 0 and 1.

So factors of 2 make sense because you have to read 4 bytes to get enough info for 1 pixel. By that time you have enough info for 2 pixels.

I am just learning about this. I wanted to test and thought your results would be a great start. I may be competly wrong on the stuff above. I'd be happy to be corrected.

Thanks

5th December 2003, 05:49	#17 \| Link
trevlac budala Join Date: Oct 2003 Location: U.S. Posts: 545	Analog is not natively RGB. I believe PAL is close to YUV and NTSC is like YUV but YQI. A BT878 will create pixels in packed YCrCb 4:2:2 format. From here it converts to many formats such as YUY2, YUV12, and RGB. I think YCrCb is basically the same as YUY2. So basically, I guess one should ask a BT878 for YUY2 not RGB, if you use huffy. For Packed 4:2:2 fromats like YUY2, each macropixel is 4 bytes (16 bits per pixel) and contains 2 pixels. The byte order is Y0 U0 Y1 V0 where U and V are shared by pixel 0 and 1. So factors of 2 make sense because you have to read 4 bytes to get enough info for 1 pixel. By that time you have enough info for 2 pixels. I am just learning about this. I wanted to test and thought your results would be a great start. I may be competly wrong on the stuff above. I'd be happy to be corrected. Thanks