05-11-2016, 10:15 PM
(This post was last modified: 05-11-2016, 10:18 PM by Mike Watterson.)
ppppenguin It's actually easier to compress the data if you start with the highest possible resolution original.
Yes, compression is easier and everything is better if the source is twice the vertical and horizontal resolution.
Interlace is evil. The first step always has to be to convert to progressive, which loses information and creates artefacts. Worst for 24 fps progressive to 30i, which is why "interlace to progressive" filters are usually designed to detect if the source was film and do "inverse telecine" rather than normal interlace to progressive.
The 720p *IS* HD for people used to 480lines, especially interlaced 30 fps from 24fps film! No contest. It's unimpressive compared to decent "PAL region" 576 line DVDs from Film.
That's a strange claim. Did you mean that improved standards conversion means original format is less important? In any case for REALLY stupid production / distribution I would disagree!
Region 1 DVDs are 480 lines. If the source is film, then it's stored as progressive and the DVD player does the 3:2 pull down for interlace which creates the horrid comb artefacts on movement. Unlike VHS where the tape is mastered in evil 3:2. This is why component video and progressive 480p DVD players really took off in USA. If you have an analogue CRT/TV and only "PAL region" DVDs then there is no point to a progressive DVD player ... but see below!
"PAL" region DVDs are 576 lines and for transfers to film the sound pitch is usually adjusted by 24/25ths so playing the 24 fps at 25fps gives correct pitch. The vertical resolution.
The film used to be scanned at more than twice NTSC/PAL resolution before anti-aliasing and downsampling to 720 x 480 or 720 x 576. Some bluray disks sadly use this master instead of a scan at twice 1920 x 1080 (Minimum is to scan at twice target, there is a good argument now for cameras to run at twice the target resolution, x4 the number of pixels).
The stupidities:
1) "PAL Region" DVDs made by standards conversion of the Region 1 "NTSC 480 30i" video, only acceptable for video source, totally insane for film, as not only is it worse than 30% less resolution than possible, you have a "shimmer" effect especially on horizontal movement.
2) Region One (or Region 0) "NTSC 480 format" DVDs of Film source sold Retail in Europe: BluRay players unlike DVD are unlikely to be region free, though they will play Region 0. Unless you have a progressive DVD player (or one with decent HDMI built in) and component or BluRay it will look rubbish with comb artefacts.
3) Total madness: Film source mastered as 480i on DVD, poor even on a progressive DVD player with component.
I found when we switched from analogue SD CRT to LCD HD screen that our SCART output DVD player (even in RGB) was much poorer than the Progressive component DVD player even for "PAL Region" DVDs. It outputs at 1440 x 576p or 1440 x 480p if the source is film and properly mastered. For interlaced video originals (a minority of our DVDs) it outputs at 1440 x 576i or 1440 x 480i.
The HD TV obviously has no native interlace mode. It has no per-pixel "Zoom out" mode to suit VHS (NTSC or PAL) better. It's noticeably better with 1080 content and progressive content. Same is true for my VGA CRT running at 1920 x 1080 x 50p from USB DTT stick, DVDs and SD or HD from Satellite (2 x PCI satellite DVB-S2 cards).
576i SD transmissions, interlaced DVDs and all VHS look better on the 28" CRT.
The source isn't anything like irrelevant.
Yes, compression is easier and everything is better if the source is twice the vertical and horizontal resolution.
Interlace is evil. The first step always has to be to convert to progressive, which loses information and creates artefacts. Worst for 24 fps progressive to 30i, which is why "interlace to progressive" filters are usually designed to detect if the source was film and do "inverse telecine" rather than normal interlace to progressive.
The 720p *IS* HD for people used to 480lines, especially interlaced 30 fps from 24fps film! No contest. It's unimpressive compared to decent "PAL region" 576 line DVDs from Film.
Quote:As compression improves the original format matters much less.
That's a strange claim. Did you mean that improved standards conversion means original format is less important? In any case for REALLY stupid production / distribution I would disagree!
Region 1 DVDs are 480 lines. If the source is film, then it's stored as progressive and the DVD player does the 3:2 pull down for interlace which creates the horrid comb artefacts on movement. Unlike VHS where the tape is mastered in evil 3:2. This is why component video and progressive 480p DVD players really took off in USA. If you have an analogue CRT/TV and only "PAL region" DVDs then there is no point to a progressive DVD player ... but see below!
"PAL" region DVDs are 576 lines and for transfers to film the sound pitch is usually adjusted by 24/25ths so playing the 24 fps at 25fps gives correct pitch. The vertical resolution.
The film used to be scanned at more than twice NTSC/PAL resolution before anti-aliasing and downsampling to 720 x 480 or 720 x 576. Some bluray disks sadly use this master instead of a scan at twice 1920 x 1080 (Minimum is to scan at twice target, there is a good argument now for cameras to run at twice the target resolution, x4 the number of pixels).
The stupidities:
1) "PAL Region" DVDs made by standards conversion of the Region 1 "NTSC 480 30i" video, only acceptable for video source, totally insane for film, as not only is it worse than 30% less resolution than possible, you have a "shimmer" effect especially on horizontal movement.
2) Region One (or Region 0) "NTSC 480 format" DVDs of Film source sold Retail in Europe: BluRay players unlike DVD are unlikely to be region free, though they will play Region 0. Unless you have a progressive DVD player (or one with decent HDMI built in) and component or BluRay it will look rubbish with comb artefacts.
3) Total madness: Film source mastered as 480i on DVD, poor even on a progressive DVD player with component.
I found when we switched from analogue SD CRT to LCD HD screen that our SCART output DVD player (even in RGB) was much poorer than the Progressive component DVD player even for "PAL Region" DVDs. It outputs at 1440 x 576p or 1440 x 480p if the source is film and properly mastered. For interlaced video originals (a minority of our DVDs) it outputs at 1440 x 576i or 1440 x 480i.
The HD TV obviously has no native interlace mode. It has no per-pixel "Zoom out" mode to suit VHS (NTSC or PAL) better. It's noticeably better with 1080 content and progressive content. Same is true for my VGA CRT running at 1920 x 1080 x 50p from USB DTT stick, DVDs and SD or HD from Satellite (2 x PCI satellite DVB-S2 cards).
576i SD transmissions, interlaced DVDs and all VHS look better on the 28" CRT.
The source isn't anything like irrelevant.
