Export SD 4:3 to deinterlaced 720 or 640?

[Barrythecrab]

I get both answers when researching this.
After lossless AVI capture at 720x480 and then processing... is it best to render export MP4 as 720x480 or 640x480?
My 720 exports always play as 4:3 as intended, tablet, PC, TV from a stick, but which is generally more acceptable and compatible?
Thanks,
BtC

[lordsmurf]

720x480 is the 3:2 SAR, and most devices require the 1:1 SAR / 4:3 DAR.

So 640x480 (NTSC) and 720x540 (PAL or NTSC) are what to shoot for.

[lollo]

Stay at 720x480

[Barrythecrab]

See? It’s a simple question that seems to have two answers!

[Skiller]

Almost any device of the last 10+ years able to play MP4 will play 720x480 with correct proportions, if the bitstream has the right value for SAR/PAR.

[jagabo]

If your playback devices support aspect ratio signaling use 720x480. If not (or if you want the widest possible support), resize to a square pixel resolution (eg 640x480, ~856x480, etc.)

[Hunk91]

If your playback devices support aspect ratio signaling use 720x480. If not (or if you want the widest possible support), resize to a square pixel resolution (eg 640x480, ~856x480, etc.)

Thank you Jagabo and lordsmurf for your answers as I was always wondering what should be the best resolutuion to keep the 4:3 ratio.
So 640x480 for NTSC, 720x540 for PAL and NTSC and I also used in a previous project 768x576 for PAL.

Jagabo you are talking about a 856x480 resolution for NTSC, but if I do the math, this doesn't give a 4:3 aspect ratio. Am I missing something ?

[lollo]

Why do you want to apply a lossy resizing if not needed?

[Barrythecrab]

Such a seemingly basic question, yet smart people with years of experience still have differing views.
Thank you for your opinions and maybe there is more, I’m listening.
As of now, with no complaints from anyone I’ve done capture and render for, I’m tempted to stay at 720, and they play fine on all my test devices.

[jagabo]

Jagabo you are talking about a 856x480 resolution for NTSC, but if I do the math, this doesn't give a 4:3 aspect ratio. Am I missing something ?

That's for 16:9 material. The true value is 853.333x480 but 856 is a mod 8 value more suitable for most encoders.

[lollo]

I’m tempted to stay at 720, and they play fine on all my test devices.

Good choice, but you can do better .

Crop 720 to 704 for exact proportions on final displaying, according to specification ITU-R BT.601-4 (formerly "CCIR-601" or "Rec.601")