Movie artefacts in computer screen but no artefacts in regular TV. Why?

[rohangc]

Hi. I am a total newbie to the world of movie encoding. I recently bought a few DVDs and backed them up using DVD-RB. Now, when I watch the movie on my computer using a DVD playing software like PowerDVD, I can see 'artefacts'. However, I played the same disk on my friend's DVD player on a regular CRT TV (interlaced display?), I see great picture and no artefacts. The movie itself has progressive encoding. Not that I am complaining, but how does this happen. If I play the same DVD say on a HDTV set, will I then see the artefacts? Please let me know. I am curious. Thanks.

[celtic_druid]

Regular CRT TV's are much more forgiving.

[Mug Funky]

if the artefacts are in light areas or highly coloured areas (fire and explosions are classic examples of the colours being highly blocky but the luma not being so bad. for water the reverse is usually true), then the TV will blur them out.

what connection are you using? composite (RCA leads) and YC (s-video) will blur colours a fair bit, component not so much but still there. TVs just pwn the chroma a fair bit - it takes a very good TV to see chroma artefacts.

[Guest]

I can see 'artefacts'. Tell us what you see. We are not mind readers.

[setarip_old]

@rohangc

Hi!

I recently bought a few DVDs and backed them up using DVD-RB. Now, when I watch the movie on my computer using a DVD playing software like PowerDVD, I can see 'artefacts'.

Do you see the same artifacting if you play the original, commercial DVD on your computer?

[E-Male]

besides the technical differences between a pc-monitor and a TV there is a 2nd point:
you mostly watch TV from more far away, so you miss more details, including artefacts

[rohangc]

Tell us what you see. We are not mind readers.

I can see slight blotches in uniformly colored areas. For example, if the background is blue, I can see blue blocks. Plus, in some cases there are edge artefacts-blocks around edges of faces and other objects. Sometimes I also see discoloration-for example, very light blue pixels where it is supposed to be uniformly green.

Do you see the same artifacting if you play the original, commercial DVD on your computer

No. The original DVDs are much better then the backed up ones-but I know that this is due to transcoding.

what connection are you using? composite (RCA leads) and YC (s-video) will blur colours a fair bit, component not so much but still there. TVs just pwn the chroma a fair bit - it takes a very good TV to see chroma artefacts.

Yes, my friend's DVD player is connected to the TV by RCA cables.

The question I actually wanted to ask (and stupidly forgot to ask) was whether the same artefacts that are visible on my CRT computer monitor will be visible on big HDTVs. I don't own an HDTV and was curious to know this.

[Mug Funky]

yes they will be visible on an HDTV. even HD CRTs have enough resolution to show artefacts on any source that has them... which is funny because so many people buy HDTVs to watch DVB on, which is pretty much always many-times recompressed, and at a low bitrate (though some of it looks awesome at 6500 mbps from digibeta source. as good as most DVDs, and better than a fair few of them. if only they wouldn't apply such heavy dynamic compression on the audio...)

[CWR03]

You said you see artifacts on your PC screen using a DVD playing software like PowerDVD - did you try only PowerDVD? Mine gives artifacts on all playback including the original DVD with PowerDVD. Try another software player and see if it's better.

[E-Male]

"funny because so many people buy HDTVs to watch DVB"
very true
i remember my girlfriend saying that those new TVs she saw have so low quality
i explained to her that they actually have 'too good quality'

[Mug Funky]

although a lot of new TVs have really naff digital filters that do more harm than good... broadcast TV has no interference, but it's got no detail either.

noise on a TV is uncorellated (usually) and going at 50/60 hz, so the human eye has plenty of chance to filter it out on it's own.

i follow the "signal until proven noise" philosophy :)