Tv-out Adapter Question.


<Off Topic> Has anyone noticed that movies (and probably everything) are stretched (vertically) when they are put on TV? Mine are... Do you think it would be a faulty Adapter, GP2X, or what? (at the moment I just squish them when I encode them for it, but I'd rather I didn't have to.. does any else have this problem? It would make sense that the GP2X would have an option to resize the screen, like what's on a computer monitor, but I haven't found anything.)
 
Well, I do remove the black bars, but I don't think that's it.

I just tried with a truly 4 x 3 movie (oddly enough.. I only had one) and I still had issues. Here are two pictures (one from the TV and one from the GP2X's LCD) to show you what I'm talking about... Mainly note the shapes of the tires, (they're oval) It's normally the most obvious when it shows a TV on screen, and you can tell that it's not the correct dimensions. (but I doubt that this movie has any TVs)



Oh, and I know, my camera's crap at taking pictures.. for one, it's a movie camera, and second, I was taking pictures of screens, and that never turns out well.

(And I think I should also say that I searched the forums for stuff involving "Stretched TV output" and similar combinations without finding anything relevant, so if anyone has mentioned this before then I'm sorry)
 
what sort of tv is that on ?
widescreens can alter the aspect ratio (cimena/zoom modes) that could be the problem (im not sure what aspect the gp2x outputs to tv, maybe the source)

Edit: the tv version just looks like its suffering from the black bars being missing

Edit2: squashed and added black bars it looks like the 2x lcd http://img129.imageshack.us/img129/9743/tvzp1pd4.jpg
that is weird though. it just looks to me like its being 'stretched' vertically to fit the screen and not having any black bars it turns out weird on a tv screen :S

It would be nice to try that movie in VLC (or a similar program) that can Force the aspect ratio, then try forcing it to 4:3 and see if it changes (it shouldnt) or try 16:9 and see if you can simulate the same problem on the pc screen, then you can find the reason for certain and rip accordingly
 
Extremely good question DawnOfTheRent. I don't want to break your question because it's a good one. Anyone that's able to help this guy figure this out, give it a go.

I just have a quick question. I'm sorta talkin out my ass here but It's still a concern.

A s-video cable cuts the screen in half vertically into 2 different signals from what I understand. and each signal takes one side of the screen making it 2 halfs. A regular composite wire only has one signal.

Here's my concern. If I plug a composite into a s-video adapter. Won't I only see one half of the screen or will it convert the signal completely? I hope somebody understands what I'm saying.

Basically I'm afraid that due to the adapter. I'm going to cut off half of my screen because of the s-video converter plug. Please let me know.
 
no it will just work normally...

afaik it splits the colours, (if your tv doesnt like svideo at all, it will give you a greenscreen or similar horrid colour)

"The luminance (Y; greyscale) signal and modulated chrominance (C; colour) information are carried on separate synchronized signal/ground pairs
In composite video, the luminance signal is low-pass filtered to prevent crosstalk between high-frequency luminance information and the color subcarrier. S-Video separates the two, and detrimental low-pass filtering is unnecessary. This increases bandwidth for the luminance information, and also subdues the color crosstalk problem. The infamous dot crawl is eliminated. This means that S-Video leaves more information from the original video intact, thus having a much-improved image reproduction compared to composite video."

"Because it is very simple to convert S-Video to composite signal (just the logical merging of the two through a filter capacitor is required), many electronics retailers offer converter adaptors for signal conversion. No conversion will improve image quality, but will allow connecting to otherwise-incompatible devices."

http://en.wikipedia.org/wiki/S-video
 
(Sorry about the late answer,.. I had other things that needed doing)

Forcing 4 x 3 does stretch it a little, but it would be completely unnoticeable if it wasn't for little, vertical, black bars that came up on the sides of VLC (I was expecting something like this, since the movie isn't truly 640 x 480, I shrunk it to 608 x 448). It's no where near as stretched as it is from the GP2X.

(in the end, I could tell more difference between it and the TV out picture, than it and the LCD picture)

I've been adjusting my encodings to squish the aspect down, So this isn't really a problem of playing ugly videos on my GP2X, it's just something I've been wondering about (The biggest problem of it is that I have to do two separate encodes for my movies.. one for the computer, and one for the GP2X.. but I can live with that pretty easily)

I used the photo viewer on the TV and they look the same as they do on the LCD (or shown with any other device) so I doubt it's hard ware.

I checked the source movie, and it had no black lines (truly full screen, I'm going to set up an encode for tonight and have everything remain as close to the source as possible and see how it looks) But for now I'm pretty sure it's still not the encoding.

And since this was never complained about before then I'm guessing I'm the only one with the problem, which means that it can't be a bug in the movie player.

Also, I use a NSTC 4 x 3 TV with an S-video in. (I've tried it with both a converter, and straight through the S-video). The TV is also hooked up to my computer, so I tested the movie with VLC straight on it, and it worked just fine.

Picture as proof:



(Thanks for the ideas. I'm still thinking,..)

I'm curious what Codecs you use, I've used both XviD and DivX to make sure I tried as many variations as I could think of (but I'm better with XviD, so I use that the most). In the settings I have options for optimizations for "MMX, Integer SSE, SSE, SSE2, 3D Now!, and 3D Now! 2" currently I have the optimizations set to "automatic" which could be a mess up, since It's probably detecting what my computer can do and is encoding the movie for it instead of the GP2X, but really I know nothing about this. Also I remember tinkering with an option I think was called pixel shape (I never noticed any change in how a movie looked though) I can't find the option now,.. I'm guessing it was on a previous version of the codec that I had before I updated (I am now using Nic's 1.1.0 build)
 
http://pw.gptheatre.co.uk/Port%20Washington%20%5bBIG%5d.avi

Ok, I tried a different encoding (maintained the aspect in every way), it still streached. I downloaded this earlier today, and decided to give it a shot on TV-out, and it also was streached, (of course, the whole thing played quite choppily, and it froze less than a minute into it, (could have been batteries, not sure,.. the whole encoding's odd, it uses a 99Kbps MP3... I've never seen that rate before in my life. I also doubt they would need any audio over 24kbps, but oh well, it's their encoding..) At some point in my life I'll try it with the power supply. If it still plays badly then I'll run it through Pocket DivX, but I don't expect anything (aspect wise) to improve.

I'm thankful for all the suggestions, but unless if anyone has any other ideas I'm just going to declare my hardware defective and move on.

Thanks, Daniel
 
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