17.10.2018, 16:41
Hi,
I don't think i blamed Hybrid, did i ? if so, excuse-me, it was not my intention, i'm just trying to understand how all this works & so i ask (too many ?) questions...
So I re-read https://en.wikipedia.org/wiki/Pixel_aspect_ratio many times to try to understand how it works.
assuming SAR × PAR = DAR.
if i understand well :
- my 720x480 source comes from a NTSC LD source & has a PAR=1 (analysed by Hybrid) ; if a circle is flat, it's because of the SAR=720:480=3:2 ? it should be 640x480 with a SAR=4:3 ?
- assuming that, what can i do in Hybrid to correct that ?
-->i see 2 ways :
1/ modify the resolution (= SAR) setting "crop/resize->base->picture resize->target resolution=640x480"
2/ modify the PAR = DAR/SAR = (4:3)/(3:2)=8/9=8:9 ie. 0,889
ok ?
1/it works if "crop/resize->base->picture resize->auto adjust" is disabled ; i didn't see this parameter at 1st, so i had as a result a 640x428 video with a PAR = 1, and i thought it didn't work...
2/so the forum told me to use the 2nd solution "crop/resize->base->Pixel Aspect Ratio->input PAR = 8x9" - which worked, and the result is a 720x480 video with a PAR=0,889 (NOTA : with this solution we don't need to encode, so it's quicker !)
Let's suppose i take now the 720x480 video with a PAR=0,889 as source.
I have to crop this video (left=26 & bottom=4)
the only thing i see to do is to set the 2 crop parameters + set the input PAR during an encoding task, right ?
that means :
- "crop/resize->base->picture crop->left=26 & bottom=4"
- "crop/resize->base->Pixel Aspect Ratio->input PAR = 8x9" -> in fact, "input PAR" should already be set by Hybrid...
--> so the result should be 696x476 with a PAR=0,889, right ?
I will try this ASAP again
My understanding is that it isn't a problem to have a video with a PAR <> 1 ?
won't it be a problem if i split this video in multiple videos ?
regards
I don't think i blamed Hybrid, did i ? if so, excuse-me, it was not my intention, i'm just trying to understand how all this works & so i ask (too many ?) questions...
So I re-read https://en.wikipedia.org/wiki/Pixel_aspect_ratio many times to try to understand how it works.
assuming SAR × PAR = DAR.
if i understand well :
- my 720x480 source comes from a NTSC LD source & has a PAR=1 (analysed by Hybrid) ; if a circle is flat, it's because of the SAR=720:480=3:2 ? it should be 640x480 with a SAR=4:3 ?
- assuming that, what can i do in Hybrid to correct that ?
-->i see 2 ways :
1/ modify the resolution (= SAR) setting "crop/resize->base->picture resize->target resolution=640x480"
2/ modify the PAR = DAR/SAR = (4:3)/(3:2)=8/9=8:9 ie. 0,889
ok ?
1/it works if "crop/resize->base->picture resize->auto adjust" is disabled ; i didn't see this parameter at 1st, so i had as a result a 640x428 video with a PAR = 1, and i thought it didn't work...
2/so the forum told me to use the 2nd solution "crop/resize->base->Pixel Aspect Ratio->input PAR = 8x9" - which worked, and the result is a 720x480 video with a PAR=0,889 (NOTA : with this solution we don't need to encode, so it's quicker !)
Let's suppose i take now the 720x480 video with a PAR=0,889 as source.
I have to crop this video (left=26 & bottom=4)
the only thing i see to do is to set the 2 crop parameters + set the input PAR during an encoding task, right ?
that means :
- "crop/resize->base->picture crop->left=26 & bottom=4"
- "crop/resize->base->Pixel Aspect Ratio->input PAR = 8x9" -> in fact, "input PAR" should already be set by Hybrid...
--> so the result should be 696x476 with a PAR=0,889, right ?
I will try this ASAP again
My understanding is that it isn't a problem to have a video with a PAR <> 1 ?
won't it be a problem if i split this video in multiple videos ?
regards