Fix'd. 4:3 with a 1.0 PAR with PAL footage is 768x576. 720x576 is just the standard resolution with the proper PAR set.Qyot27 wrote: 1) I'd recommend stressing that determining proper aspect/cropping is easiest if it is 1:1 - the bolded sentence is a good reminder, but perhaps elaborate on why it's easier with 1:1. If you know that DVDs only come in 4:3 or 16:9 (because even though MPEG-2 does support 2.21:1 flags, the DVD standard does not), and you know what the proper 1:1 size is for your region when dealing with those frame geometries (640x480, 848x480, 768x576, 1024x576), you can pre-resize the video, and then the cropped size is already in the correct ratio and it can be resized proportionally to the desired final resolution without issue.
I've been wondering about the mod16 issue as of lately... that's 'cause 1080p isn't mod16 - the mod16 res would be 1088, hence why on blu-ray discs the actual resolution is 1088, and gets cropped by 8 over playback, or, well, that's to my understanding. Despite of that, I do see a lot of actual 1920x1080 videos all over the internet - it's just a standard resolution. So my point would be, as long as it's at least mod8 there shouldn't be any issue. Of course mod16 is still recommended, but if it's mod8, I think it's still fine, especially when it comes to "standard" mod8 resolutions.3) A little expansion on mod16 might be in order, primarily concerning any borders that need to be put back on the video, such as for manual letterboxing in the event using a 16:9 flag isn't an option. 640x368 may be a mod16 res, but to make it 640x480, neither of the borders - if the same amount of pixels on both sides - are. Either the top or bottom would need 8 more border pixels than the other, or you need to use 640x352 instead (as 640x352 is also mod16, and both of the borders are as well).
