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View Full Version : newbie questions about SAR and MOD16 resolution


kotrtim
4th January 2006, 13:45
I'm not gonna start a new topic

This is a newbie question, is mod16 compulsory for x264 like it is for XViD (for best compability)?

and another question, are these values correct for SAR
I learnt it from YAMB "View and edit Command Line"

16:9 NTSC = 40:33
16:9 PAL = 16:11

Picture aspect ratio is really very confusing!!!
how come 16:9 for DVD is 40:33 for MP4?
Are there any good guides for this, I tried to do google search and found a few websites, still don't really understand....I can find no website mentioning 40:33 or 16:11!

charleski
4th January 2006, 14:42
This is a newbie question, is mod16 compulsory for x264 like it is for XViD (for best compability)?
TBH I still use mod-16 resolutions, though from looking at the x264 changelog you should be able to use anything that's a multiple of 2.

and another question, are these values correct for SAR
I learnt it from YAMB "View and edit Command Line"

16:9 NTSC = 40:33
16:9 PAL = 16:11

Picture aspect ratio is really very confusing!!!
how come 16:9 for DVD is 40:33 for MP4?
Are there any good guides for this, I tried to do google search and found a few websites, still don't really understand....I can find no website mentioning 40:33 or 16:11!
SAR is just a number that tells the playback device how to convert the video you have (eg 720x480) into the size that you want, so those numbers are right for video in DVD resolutions.

bond
4th January 2006, 20:31
I'm not gonna start a new topicyou better should, if the content of your post doesnt fit the topic of the thread

split

foxyshadis
4th January 2006, 22:45
x264 will extend the clip to mod-16. It may zero-extend but I think it repeats the last line. Either way the encode will suffer from bad motion vectors and quantization on those edges, but it's your choice if you want to use it.