540p stream vs 576p PAL DVD quality

[Tz2002]

I'm re-watching some old shows and I have DVDs and streaming services. I'm playing either video on a PC connected to a TV so hardware restrictions are not an issue.

The DVDs are PAL 720x576, Netflix offers the video in 940x540.

There are a few things that I have been considering:

For the DVDs:

- DVDs are more often than not interlaced (or at least look odd unless I enable interlacing in my player, different DVDs seem to be interlaced in different ways. Some are very obvious, some are less...)
- DVDs use the older mpeg2 codec (not that this matters, but it means we can't just do a bitrate comparison)
- PAL DVDs use non-square pixels for widescreen SD content (which 90% of my DVDs are)
- DVDs are compressed to fit on the disk


- Netflix streams are not interlaced
- Netflix uses the more modern x264 codec
- Netflix videos are not interlaced and there are no non-square pixels
- Netflix has potential bandwidth restrictions, but providing high bitrate SD content is not going to be much of a problem for a service that generally host 1080p and 4k content.

On pure pixels, 960x540 gives about an extra 25% pixels to store the data ( 720x576=414720, 960x540=518400) so in theory should be the better choice.

So, my question is, assuming that Netflix use an original master rather than encoding their own video from the DVD, should I watch Netflix 540p versions instead of my DVDs?

[smrpix]

Why not switch back and forth and compare a few episodes? At this point Netflix is probably running better, more recent transfers, though it may or may not have anything to do with the numbers you're citing.

[DB83]

What you forget, or do not know, is that your 720*576 16:9 dvd actually displays as 1024*576 or, as you put it, in pure pixels 589,824. Some 13% MORE than Netflix.

[jagabo]

What you forget, or do not know, is that your 720*576 16:9 dvd actually displays as 1024*576 or, as you put it, in pure pixels 589,824. Some 13% MORE than Netflix.

Nonsense. Virtually nobody has a 576 line display these days. It's more likely his DVDs are displayed at 1920x1080 or 3840x2160. So are his Netflix streams if he's watching them on TV. But we know that the DVD is limited to 720x576 resolution at best. Whereas the Netflix streams might have more resolution horizontally (less vertically), depending on what source was used.

There are many many other issues (frame rate, field blended NTSC/PAL conversions, film vs. video source, etc.) that are important also. There is no one-size-fits-all answer to the original question of which is better.

[DB83]

Pray tell why this is nonsense ?. The OP compared 720*576 to 960*540. I merely pointed out the 'pure' display and not some theoretical upscale. I do watch my dvds on a 1920*1080 display but under the hood the 16:9 source is still 1024*576. One advantage of starting with 960*540 will be to make that eventual upscale easier.

[Tz2002]

What you forget, or do not know, is that your 720*576 16:9 dvd actually displays as 1024*576 or, as you put it, in pure pixels 589,824. Some 13% MORE than Netflix.

sure, but a 720x576 image is 1440x1152 if you stretch it to be that, you're not actually adding any more detail to the image, it's just that the DVD is designed to be stretched horizontally. A genuine 1024x576 image will have more detail that a 720x576 image stretched horizontally.

I'll compare a few side by side, but I guess it will depend too much on the individual sources, I just wondered if there was a rule of thumb. For example, a (decent bitrate) 720p stream is going to be better than a DVD so there has to be a general cut off point.

[Cornucopia]

@DB83, under the hood ALL PAL DVDs are 720x576 max (and NTSC = 720x480 max). That is immutable. For PAL DVDs, the 720x576 when shown on a square pixel display stretches to 1024x576 (in 16:9) or 768x576 (in 4:3), but the inherent true horizontal resolution is still 720. They're ALL being stretched to accommodate conversion from non-square to square pixel. That 1024 figure has always been the square pixel equivalent.
Both DVD rez and Netflix 920x540 rez must and would be resized to fit standard 720p, 1080p, or 2160p displays. Upscaling is upscaling - about the only thing that makes it "easier" is if it is a simple 2:1, 3:1, 4:1 ratio vs. odd ratios. In that way, the Netflix has the advantage when going to 1080p or 2160p.

Also @Tz2002, note: ALL DVDs are non-square, whether 4:3 or 16:9, whether NTSC or PAL. And all DVDs are interlaced-ENCODED, whether the underlying source is interlaced or progressive.
ALL DVDs, Blurays, and UltraHD Blurays are compressed to fit on the disc. But then again, ALL Netflix streams are compressed to fit in the allocated internet bandwidth pipeline.
Neflix uses a number of codecs, though all of them are more efficient than MPEG2.
Interlaced DVDs should not be an issue with a standard DVD player, even going to a normal, modern, progressive display, as the hardware in either the DVD player or the TV (or both) are capable of realtime deinterlacing.
All Netflix streams are progressive, whether their original material was progressive or interlaced, as Netflix has already done the deinterlacing when they converted it to their streaming format. It could be a good job or not, depending.

It is ILLEGAL for companies like netflix to re-encode and re-stream/re-broadcast from such consumer products as DVD masters (and they would get sued very quickly and visciously if they did that), so ALL titles being presented on their site must come from either the same master that the DVD came from, or a re-mastered version. Re-mastering could be better, equal, or (occasionally) worse.

Scott

[DB83]

Ok. But the point I have been, probably badly, trying to put over is that to adequately compare two items they must both have a common attribute. So you can not directly compare non-square dvd pixels with square HD ones. The true comparison is only made when you use the square equivalent of the non-square pixels.

[aedipuss]

Ok. But the point I have been, probably badly, trying to put over is that to adequately compare two items they must both have a common attribute. So you can not directly compare non-square dvd pixels with square HD ones. The true comparison is only made when you use the square equivalent of the non-square pixels.

? it's really easy to compare. take a screenshot of each displayed at their same native 480(or 576) resolution with the same program(vlc?).