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iPod Didnt they say the res is 640x480?

ImNoSuperMan

ImNoSuperMan

macrumors 65816
Original poster
Dec 1, 2005
1,222
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I was just browsing through the new iTMS and noticed this:-
Picture 2.jpgPicture 3.jpgPicture 4.jpg
How can they claim it to be Widescreen and on the other hand claim the resolution be 640x480. Can someone tell me what resolution will such supposedly WideScreen movies sport. will it be 640x400 or 720x480???
 
vikas soni said:
I was just browsing through the new iTMS and noticed this:-
View attachment 57259View attachment 57261View attachment 57262
How can they claim it to be Widescreen and on the other hand claim the resolution be 640x480. Can someone tell me what resolution will such supposedly WideScreen movies sport. will it be 640x400 or 720x480???
Click to expand...

I noticed that as well. I'm not keen on dropping $10 to find out though. Theories: anamorphic encoding? Letterboxed (shudder)?

I'm headed home from the office right now, but I wonder if HD TV shows are going widescreen as well (Lost, 24, etc)... I'll bite for anamophic DVD quality lost in 5.1 at $2 per 'sode...
 
It's either letterboxed or anamorphic.

Letterboxing is when black bars are placed on top and bottom making the res of the image 640x360.

Anamorphic is a vertically stretched image that will widen to fill the width of the screen. black bars are actually a lack of data rather than bars added in.

This is a very simple explaination... I'm sure someone will follow up soon with more details.
 
Can't someone just watch a trailer? (Are the trailers in the high-res?)

I can't watch them as I haven't installed the new QT yet.
 
There is a note on this page

" 1. Exact resolution depends on aspect ratio."

It seems they won't all be 640x480
 
Maybe it's just always 480p (480 lines of resolution horizontally) regardless of the width of the movie.
 
esaleris said:
Maybe it's just always 480p (480 lines of resolution horizontally) regardless of the width of the movie.
Click to expand...
Previously for TV shows it was the other way around widescreen meant keep 320 horizontal, less vertical. :(

B
 
EssentialParado said:
Can't someone just watch a trailer? (Are the trailers in the high-res?)

I can't watch them as I haven't installed the new QT yet.
Click to expand...

The trailers seemed to be linked to separate files - that is they're not like the TV show trailers where it's just a clip, it's the theatrical trailer. For example, check out Grosse Point Blank (great movie)... the trailer is a 4:3 video but the movie is listed as being widescreen.
 
It's the same thing with DVDs. The video is NTSC quality (640x480). But you'll only get that resolution if it's "full frame". If you have a widescreen video, then you'll get less vertical resolution.

And no, they don't encode the black bars in the video, that'd be a waste of disk space. But yes, when that video plays, it'll probably show black bars. Depends on your screen.
 
MarkCollette said:
It's the same thing with DVDs. The video is NTSC quality (640x480). But you'll only get that resolution if it's "full frame". If you have a widescreen video, then you'll get less vertical resolution.

And no, they don't encode the black bars in the video, that'd be a waste of disk space. But yes, when that video plays, it'll probably show black bars. Depends on your screen.
Click to expand...

DVDs use anamorphic encoding, so they use the full 640x480 pixels of resolution for widescreen video. I don't feel like typing it all again, if you want an explanation of anamorphic encoding search for recent posts by me. Point is that a 640x480 NTSC file can be "tricked" into holding full resolution widescreen video.
 
mrgreen4242 said:
Point is that a 640x480 NTSC file can be "tricked" into holding full resolution widescreen video.
Click to expand...
That's 'cause DVDs native resolution is actually 720x480. :p

It only turns into 640x480 when you try to rip it into MPEG-4 or somethig like that.

B
 
mrgreen4242 said:
Nope. DVDs are in 640x480, you can do the same search... oh hell, read here: http://en.wikipedia.org/wiki/Anamorphic
Click to expand...
Sorry. That link doesn't have it, but this one does. http://en.wikipedia.org/wiki/DVD-Video

The typical video resolution for an NTSC disc is 720 × 480, while a PAL disc is 720 × 576. The specifications for video files on a DVD can be any of the following:

* Up to 9.8 Mbit/s (9800 kbit/s) MPEG-2 video
* Up to 1.856 Mbit/s (1856 kbit/s) MPEG-1 video

* PAL:

720 × 576 pixels MPEG-2 (Called full D1)
704 × 576 pixels MPEG-2
352 × 576 pixels MPEG-2 (Called Half-D1, same as the China Video Disc standard)
352 × 288 pixels MPEG-2
352 × 288 pixels MPEG-1 (Same as the VCD Standard)

* NTSC:

720 × 480 pixels MPEG-2 (Called full D1)
704 × 480 pixels MPEG-2
352 × 480 pixels MPEG-2 (Called Half-D1, same as the China Video Disc standard)
352 × 240 pixels MPEG-2
352 × 240 pixels MPEG-1 (Same as the VCD Standard)
Click to expand...

You're getting confused by the fact the the DVD format is optimized for widescreen and is compressed horizontally for display on standard SDTV 4:3 displays.

B
 
balamw said:
Sorry. That link doesn't have it, but this one does. http://en.wikipedia.org/wiki/DVD-Video



You're getting confused by the fact the the DVD format is optimized for widescreen and is compressed horizontally for display on standard SDTV 4:3 displays.

B
Click to expand...

I'm pretty sure that NTSC ONLY allows for a 4:3 signal, and DVDs are fully NTSC compliant. 4:3 with a 480 pixel height is 640 wide. Non square pixels are used to get a 720x480 video signal in there, though, which is part of the spec, which I think is what is confusing... this site explains it in pretty decent plain language: http://www.dvddemystified.com/dvdfaq.html#3.4.1

Either way, there is little doubt that (region 1) DVDs are NTSC and NTSCS only defines a 4:3 format, but the DVD spec makes a nice hack of this with anamorphic encoding to allow 720x480 pictures on a 640x480 frame.
 
mrgreen4242 said:
I'm pretty sure that NTSC ONLY allows for a 4:3 signal
Click to expand...
Yes, but NTSC is an analog spec, and thus the horizontal resolution is effectively unlimited. (it knows nothing about pixels, only scanlines).

Have a look at this link, which tells you how to do the anamorphic squeeze on your analog SDTV to get higher horizontal resolution from your DVDs.

http://gregl.net/videophile/anamorphic.htm

B
 
balamw said:
Yes, but NTSC is an analog spec, and thus the horizontal resolution is effectively unlimited. (it knows nothing about pixels, only scanlines).

Have a look at this link, which tells you how to do the anamorphic squeeze on your analog SDTV to get higher horizontal resolution from your DVDs.

http://gregl.net/videophile/anamorphic.htm

B
Click to expand...
Ug, I just had a whole long post written, but I deleted it, this is stupid. The DVD spec is terrible. It calls for a 1.5:1 file, but mastered to work on a 1.33:1 display. In turn, DVDs take a 1.78:1 image, squeezes it to be a 1.33:1 images, which is then encoded to a 1.5:1 file.

Regardless of how you look at it, the Region 1 DVD is specifically mastered around NTSC, which is a 4:3 format. Any widescreen content put onto a DVD has to be adjusted, one way or the other, to fit into that aspect ratio.
 
Here's a screen shot playing a movie I just downloaded at Actual Size vs photo shop file 640x480 at 100%.

Looks like it's 640x270.
 
It's going to be interesting to see how the picture quality of these compare to DVDs, as the eye sees it. The resolution will be close, but probably slightly smaller than DVD, from what you guys are saying. Plus, different codec, bitrate, total file size. Nice to see if there's less motion artifacting since no MPEG2.

The only obvious loss is that it's only stereo sound, with no 5/6/7.1 surround. I've never had a spiffy sound system, so won't change anything for me, but I can see how others might not like that.

Do they say anywhere how fast your computer has to be to play the video?

Also I'd love to see how these compare to typical bit torrent downloadable DviX encoded videos.
 
Bibulous said:
Here's a screen shot playing a movie I just downloaded at Actual Size vs photo shop file 640x480 at 100%.

Looks like it's 640x270.
Click to expand...


So how's that compared to a normal DVD I watch on my mac? If you take the downloaded iMovie and go full screen does it get pixelated or is it comprable to a DVD. (I read through the earlier discussion about DVD resolution but I'm too lazy to think through all that. Plus real world examples are always best).

Also, can iMovies be burned to DVD's and watched on the tv (legally and physically possible)?
 
Bibulous said:
Here's a screen shot playing a movie I just downloaded at Actual Size vs photo shop file 640x480 at 100%.

Looks like it's 640x270.
Click to expand...

Grrrr.. Cant believe it. So Apple is now trying to sell 270p movies as 480p one. Compared to regular Widescreen DVDs it`s half the resolution. Do they call 50% resolution as nearly DVD quality.:mad:

Thank God they dont offer anything in India. Or else I`d be really mad at Apple right now.
 
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