Aspect Ratios (TMPGenc)

[migf1]

Hi all, it's been a while since I've posted to the forum for the last time, so I apologize if this has been answered in the meanwhile....

According to Adobe Premiere's documentation, there are two types of aspect-ratios: one referring to the full frame and one referring to each one of the pixels consisting the frame (it calls that Pixel Aspect Ratio).

My questions have to do with TMPGenc. Which one of those two types does TMPGenc refer to as "aspect ratio" in its Video and in its Advanced tab?

Also, what's the difference between the aspect-ratios in those two tabs? Do they both refer to the source file or does one of them refer to the desired AR of the output? If so, which one is which (source and output, I mean) and how can I see what AR my original source file has?

Lastly, do those two values of aspect-ratio (in Video and in Advanced tab) have to be always the same?

Thanks in advnace and sorry for the... question bombing

Best regards...

[reboot]

TMPGEnc has two places for aspect ratio. AFAIK, they both refer to full frame, not pixel...
The "Video" tab is the output, which is standardised at 352x240 for VCD, and 480x480 for SVCD.
The "Advanced" tab is where you specify the aspect ratio of the original source avi.
If the original is 16:9, set it that way, and tmpgenc will put the black bars top and bottom, which are needed to view the finished (s)vcd. If you don't specify the aspect ratio of the original correctly, your finished mpeg will be either stretched vertically or horizontally.
If you don't mind a bit of stretching, you can specify 4:3, or even 2.11:1 instead of 16:9, and get a larger picture, with smaller bars top and bottom.
This is provided you choose "Full Screen (With aspect ratio)".

[migf1]

Thanks for the valuable info reboot!

Should I rely on TMPGenc's indication about the AR of the source file (in the Advanced tab)? Does TMPGenc reliably identify the AR of the source file?

Best regards...

[reboot]

No. I have found that TMPGEnc hasn't a clue what the source aspect is.
I generally use GSpot to accurately tell me what the original is, and then manually set it in TMPGEnc. Let it encode a few seconds, abort, and check the aspect of the resuting mpg in WMP (or other player).
I find that WinDVD, and PowerDVD both show an accurate finished product, so you know what it's going to look like on the TV.
Lately I have been using MainConcept MPEG Encoder instead of TMPGEnc. It's faster, and allows you to manually set the aspect ratio of the product to any setting. Particualrily good for some videos I have that are strange sizes, such as 576x304 (1.89:1 or 36:19), and look horrible at 16:9 or 4:3, or I can stretch them slightly to 2.11:1 which isn't so bad.

[iThinkYouBrokeIt]

When i have something in an unusual aspect ratio what i do is this:

on the "source settings" tab, i set it to 1:1 VGA
then on arrange setting, i set it to "center (custom size)"
then, i use a calculator (just the windows calculator) to find out what the correct size should be.
for example, if i have a movie trailer that is 2.35:1, and i am putting it on svcd, i use the calculator...
i divide 640 (since the svcd format image is "stretched" to 640x480 to be displayed properly) by 2.35
what i get is approximately 272.
640 / 2.35 = ~272

then i simply change 640 to 480, since that is the actual encoding resolution, and set it to:
"center (custom size)" at 480x272. when it is played back, it will show on screen as 640x272, which is 2.35:1. the original aspect ratio.

yeah . . .

[migf1]

Guys, thank you for your answers and info!

However, aspect-ratios are troubling me since I've started messing up with video editing, some 6 months ago or so. Apart from standarized procedures with standard tools & settings for capturing, encoding and burning, there are cases where no matter how many guides and docs I read, I don't really know exactly what is going on

Ok here is an example of such a case:

Say we have found on the Internet (or have been given by a friend) a 320x240 MPEG-1 file... let's call it 'in.mpeg'. Now, say we want to convert it into a standard VCD PAL format file (352x288, 25 fps, videobr-1150kbps, audiobr=224kbps, etc)... let's call that file 'out.mpg'.

a) Do I need to know the Pixel Aspect Ratio (PAR) of 'in.mpeg'? If so, how can I look for it and how do I benefit from knowing it?

b) How do I find out the AR of 'in.mpeg', so I can pass it to TMPGenc's Advnaced tab?

NOTE: GSpot doesn't open mpeg files, does it? Media Player Classic (which I heavily use) sometimes shows an AR indication of the files it plays, but some others it doesn't (does the latter mean that those files have AR=1:1?).
Also, is MPC showing AR or PAR? (see below why I ask this question)

There's even more confusion here (regarding the AR shown inside MPC, I mean).

If I capture an AVI file with Virtualdub (I specify framesize 352x576 but I apply 2:1 Linear Vertical Reduction during the capture, to get a somewhat richer 352x288 outcome) then MPC doesn't show any AR for the resulting AVI file (actually it never shows AR for any AVI file...does this mean that all AVI's AR = 1:1?). Now, if I open the AVI file inside Ulead Video Editor 7.01 and ouput it via VE's standard VCD PAL template into a VCD PAL compliant file, then MPC ALWAYS show an AR equal to 176:135!!! ... where does this ratio come from? It's not 4:3, it's not 16:9, it's not 1:1... what the heck is it? Is it PAR or AR? According to the standard VCD (PAL) template of TMPGenc's Video tab, the (locked) AR of the output VCD mpg-file should be 4:3, right? Does it make sense to any of you guys?

c) Assuming I've somehow found 'in.mpeg's AR (do I really need to know its PAR also?) and I pass it into TMPGenc's Advanced tab, what is the correct AR for the Video tab? Do I always leave it to the locked default 4:3 (PAL)? If so, why Ulead VE's VCD-PAL template produces files whose AR are shown as 176:135 inside MPC? Which one is right about the AR of the output, TMPGenc or Ulead VE7?

Best regards...

PS1. Isn't all that quite confusing, or is it just me? Although I'm not an advanced Video Editing guy, I figured I had more chances to clear all this mess up if I was posting my questions in the advanced section of this forum... so I did

PS2. If you're short of time, and cannot explain in details all the above mess, I would apreciate it if you could just point out the correct procedure to convert a random framesize 25fps MPEG file 'in.mpeg' into a standard VCD PAL compliant 'out.mpg', with the minimal possible loss in visual quality.

[iThinkYouBrokeIt]

you generally do not need to know the pixel aspect ratio.

if the source file is 320x240, that is 4:3
just set the source aspect ratio to 4x3.
if it is 352x240, set the source aspect ratio to 4x3 NTSC (since this is the NTSC compliant resolution for 4x3 video)
if it is 352x288, set the source aspect ratio to 4x3 PAL (since this is the PAL compliant resolution for 4x3 video)
avi video, quicktime, divx, realmedia, all generally use a 1:1 pixel aspect ratio, meaning the pixels are meant to be displayed as squares. that makes sense since they are to be viewed on a computer screen, which of course displays as squares.

[reboot]

Whew, a lot of reading.
First, I have never had cause to use pixel aspect ratio.
Given your example below, you know it's an mpeg1 file, the aspect ratio is 320x240, which is 4:3 for "in.mpg" (both numbers divided by 80 to the lowest common denominator whole number. Another way to put it, it's 1.3333333~:1 which is the same as 240*1.3333333).
Output in TMPGEnc just leave alone.
Input, in this case, would be 1:1 so that the original 4:3 ratio is maintained to the output, be it vcd, or svcd.

[migf1]

Thanks for the patience and the info guys!

However, it seems I lost it again...

Given your example below, you know it's an mpeg1 file, the aspect ratio is 320x240, which is 4:3 for "in.mpg" (both numbers divided by 80 to the lowest common denominator whole number. Another way to put it, it's 1.3333333~:1 which is the same as 240*1.3333333).
Output in TMPGEnc just leave alone.
Input, in this case, would be 1:1 so that the original 4:3 ratio is maintained to the output, be it vcd, or svcd.

So, although "in.mpg" has a 4:3 aspect ratio, I should pass 1:1 as the AR of the source file in TMPGenc's Advanced tab?

While...

if the source file is 320x240, that is 4:3
just set the source aspect ratio to 4x3.
if it is 352x240, set the source aspect ratio to 4x3 NTSC (since this is the NTSC compliant resolution for 4x3 video)
if it is 352x288, set the source aspect ratio to 4x3 PAL (since this is the PAL compliant resolution for 4x3 video)

Hmmm, those seem to contradict to reboot's suggestion of passing 1:1 as the source's AR into TMPGenc, don't they?

(grrrr... I hate Aspect Ratios ... )

...
avi video, quicktime, divx, realmedia, all generally use a 1:1 pixel aspect ratio, meaning the pixels are meant to be displayed as squares. that makes sense since they are to be viewed on a computer screen, which of course displays as squares.

Yeap, the only thing I know for sure! But I just want to make sure that I don't need to care about source's PAR when I specify an AR into TMPGEnc's Advanced tab. Do I?

Best regards...

PS. Is there a place or a site really explaining all these things?

[reboot]

Don't worry so much about PAR.
The way I understand it, your source is already 4:3 and you want a finished 4:3 VCD to play on a standalone, so you pass the in.mpg thru TMPGEnc at 1:1 to get a finished VCD mpeg1, ready to burn at the correct ratio. TMPGEnc encodes it at 352x240, 4:3.
If you were making an SVCD, then you would pass in.mpg thru TMPGEnc with a source aspect of 4:3, instead of 1:1, so that TMPGEnc encodes it full screen, 4:3 aspect ratio, because a VCD is (default) 4:3, whereas an SVCD is 480x480 (1:1), yet TMPGEnc defaults to a 4:3 display output.
This is probably clear as mud, and I might have even contradicted what I said above.
Anyhow, all I do is encode 10 or 15 seconds, abort, check in WinDVD, or other GOOD player (WMP doesn't always get aspect correct for some reason). If you have it right, then encode and burn it. If it's not right, adjust the input aspect ratio.

[migf1]

Thanks once more reboot!

Complementary to the conversation we had the last days I also did some tests and I think I may have found something. Please correct me wherever you (or anyone else) feel it's necessary...

For the source file, TMPGenc gives the following AR options in its Advanced tab:

1:1 (VGA)
4:3 525 line (NTSC)
4:3 525 line (NTSC 704x480)
4:3 625 line (PAL)
4:3 625 line (PAL 704x576)
16:9 525 line (NTSC)
16:9 625 line (PAL)
4:3 Display
16:9 Display
2.11:1 Display

Although I have no idea what the latter 3 mean (the "Display" ones), I may have figured out the former 5 (I didn't test at all the 16:9 ones).

I think that, regardless of the output (locked) AR in the Video tab, the source's AR in the Advanced tab should be passed as follows:

1:1 (VGA), if it's 1.33333 (i.e. 768x576, 640x480, 384x288, 320x240, 240x180), because 1.33333 is the AR of all valid VGA resolutions.

4:3 625 line (PAL 704x576), if it's 1.22222 (i.e. 704x576, 352x288/352x576).
4:3 525 line (NTSC 704x480), if it's 1.46666 (i.e. 704x480, 352x240/352x480).

4:3 625 line (PAL), if it's 1.25 (i.e. 720x576).
4:3 525 line (NTSC), if it's 1.50 (i.e. 720x480).


I tested all the above by capturing AVIs in the different standard framesizes (mentioned above) and by creating VCD and SVCD output files. During the tests I only used 2 of the 3 available Video Arrange Modes: the "Full screen" and the "Full screen (keep aspect ratio)"... I didn't test at all "Full screen (keep aspect ratio 2)".

So, for VCD files both modes looked ok.
For SVCD files, only the "Full screen" was creating the desired result when the source was 352x576 PAL (or 352x480 NTSC) or anything with horizontal resolution less than the SVCD standard 480.

I ended up using always plain "Full screen" (which btw was TMPGenc's suggested video arrange mode anyway).

Video arrange modes is another topic I would also like to discuss, if anyone is willing to participate.

Interestingly enough, TMPGEnc was always suggesting correctly the AR of the source file in the Advanced tab, every time I was inputing a new source file in the main window. Perhaps because I only used AVI sources with standarized framesizes, dunno.

Lastly, I noticed that TMPGenc's templates' output (locked) AR in the Video tab was "4:3 625 line (PAL)" for PAL VCDs ["4:3 525 line (NTSC)", for NTSC ones], while it was always "4:3 Display" for both PAL and NTSC SVCDs. Sadly, that doesn't really help me figure out what this AR really means or does.

Best regards...

PS. I really wish there was an in-depth dedicated guide just to the Aspect Ratios themselves (ideally coupled with their application inside TMPGenc)

[reboot]

You have now got a terrific handle on what TMPGEnc does with aspect ratios. It's actually quite good at determining the input aspect of the source, provided it is a standard size.
AFAIK, the 3 "display" options give results that can be played on the computer, but may not be completely (S)VCD compliant. I never use them. I have also found that "Full screen (keep aspect ratio 2)" does the same as the other one, and really haven't seen any differences.
Do a bit more testing. Grab any avi that is VCD standard aspect ratio. (320x240).
Encode it, with the source set to 4:3, then do it again with the source as 16:9, then again at 2.11:1 and see how the results differ.
If you really want to mess with it, use the unlock.mcf template, and further adjust the output aspect. Take your standard avi, set input to 16:9 and output to 16:9 and see what you get

There are times when one get's a completely non-standard avi, and this is where one must sort of fudge the input and output aspect ratios.
eg. a source avi that is 4:3, but has some id10t's website ad splashed all over the bottom like a watermark, but even more obtrusive. It may take up only a few lines, and actually editing it out, using a filter in VirtualDub does chop a bit off the bottom of the video, but nobody notices anyhow, and it's a lot less obtrusive than having the website ad.
I now have a finished avi, in the correct framerate, but nowhere near any standard size.
If I manually select the "unlock.mcf" template, I can now adjust the input AND output aspect ratio, to get the movie as close as possible to the correct ratio, with the black bars equally distributed top and bottom.
This is where GSpot can tell me exactly what my avi's aspect ratio is, and then allow me to do a bit of math to get the output I want.

[dafreak]

some good info here.

I have a question along the same lines.

i have an avi file that when i run it through gspot, it says that it's 4:3 aspect ratio.
I like my output to be 16:9, cuz I like the widescreen look. i usually set my output to 16:9 AR, but am confused as what to set the input AR as well as the video arrange method, under the advanced tab.

if i set the input AR to 4:3 and the VAM to full screen keep aspect ratio, would the end result come out in letterbox form?
is it bad to set the input AR as 16:9 when it's really not? What should i set the AR and VAM to be if i want the result to be letterbox?

one thing i don't want is to have video that has borders all around it, or borders on the left and right side of the screen.

[duhmez]

heres the dilly. VCD does not support 16:9, so the video IS 4:3.

under video set it to 4:3 display.
under advanced, set to 4:3 display. Thats it, not 4:3 (325 Line Pal)
Just basic 4:3 becuase that is what the video actually is. With this setup, tmpgenc will not add borders (you dont want borders added because the source is already proper aspect) and it iwll just encode the pixels as there are, after resizing. your TV will then unsquish the pixels that were stretched during the resize, and look normal.

If it's 16:9 then you have trouble. there are 3 different aspects that use 16:9 , there is 1.77:1 , 1.85:1, and 2.35:1

1.85 and 2.35 require black bars to b added AND aspect ratio set to 16:9 (it's a double whammy there) But 1.77:1 can merely be encoded as 16:9 native with no borders added at all. (16:9 display setting wil do this for you on both tabs, NOT 16:9 625 line Pal.) So If you have a divx file, divide the top by the bopttom, get the right aspect. If it's 1.85 or 2.35:1 I sugest you use avisynth to add borders to it. Tmpgenc only gets it right with one of the 3 16:9 aspects, and it's not 2:35, it either gets the 1:77 right or the 1.85 right with respect to how much black border to add.) UNderstand, 1.77:1 and 1.85:1 are VERY close in aspect, and if you don't check carefully the result, you may think you are encoding things right when in fact it is a little bit off.

the bottom line is, one the advanced tab, the settings that specify NTSC or pal in them, will add borders. the others won't. If your divx is truly 4:3, or 1.77:1, you don't want borders added. Just resize and use plain 4:3 or plain 16:9

If you want borders added choose the correct one that has PAL or NTSC in it.

[tetsuwan]

If you're planning on watching your video 4:3 or 1:1 video on a standard TV you might want to consider correcting the resize to account for TV overscan. If you're getting DV or stuff you find on the net, it probably doesn't take overscan into account and you will have the edges of your vid cut out. So you want to leave black bars on all sides. I use 328 x 224 for VCD, 448 x 448 for SVCD, and 656 x 448 for DVD (thanks to Mr Aho for the DVD specs). With Tmpgenc, use center, custom size and input the aspect ratio.

Edit: my specs are for NTSC.

[migf1]

[A bit tedious, but hopefully interesting, post]

Hi guys,

I'm back after some more tests with the "4:3 Display" AR, in TMPGenc (I also checked a bit more stuff).

I found out that with the AR "4:3 Display" TMPGenc refers to the framesizes: 352x576, 480x576 for PAL (and I assume 352x480, 480x480 for NTSC). This means that those framesizes should be removed from the categories I listed them under, in my previous post, and be put under the category "4:3 Display".

So, I think that TMPGenc uses the characterization "Display" to describe video files with:
* a valid SVCD framesize (480x576 for PAL, 480x480 for NTSC)
* and/or a valid half DVD framesize (352x576 for PAL, 352x480 for NTSC).

This argument becomes even stronger if you notice that TMPGenc's SVCD and DVD default templates ALWAYS use the (locked) "4:3 Display" value as the suggested AR for the output file.
[In the docs, TMPGEnc refers to video using this AR with the term "film" -does this mean anything special to you guys?]

NOTE:
The above does NOT seem to be the case for the 2 full DVD framesizes: 720x576/704x576 for PAL (720x480/704x480 for NTSC), which are both reported by TMPGenc having an AR of "4:3 625 line (PAL 704x576)" ["4:3 525 line (NTSC 704x480)" for NTSC]. This also removes those framesizes from the categories I listed them under, in my previous post.

So, according to my testing, the new list for source's AR in the Advanced tab becomes something like the following (for the PAL system):

1. 1:1 (VGA) - when the source's AR is 1.33333 (i.e. 768x576, 640x480, 384x288, 320x240, 240x180), because 1.33333 is the AR of all valid VGA resolutions.
2. 4:3 625 line (PAL 704x576) - when it's a valid PAL Full DVD framesize (720x576/704x576) or a valid PAL VCD framesize (352x288).
3. 4:3 625 line (PAL) - according to TMPGenc's help-file this AR should behave exactly like the AR No2 did in my tests, but it never came up as a source AR in those tests (???) [please see the comment, right after the list].
4. 4:3 Display - when it's a valid PAL Half DVD framesize (352x576) or a valid PAL SVCD framesize (480x576).

COMMENT:
According to TMPGenc's help file, the AR "4:3 625 line (PAL)" (No3 in the list, above) refers ONLY to 3 specific framesizes: 720x576/704x576 (valid PAL Full DVD) and 352x288 (valid PAL VCD).

HOWEVER, if you input a video file with any of those specific framesizes, then you'll see in the Advanced tab that TMPGenc identifies it to have an AR of "4:3 625 line (PAL 704x576)" (No2 in the list). To make things even worse, the help-file does NOT include a description for AR No2 at all!!!!

The... drama goes on if you (logically) assume that the explanation of the PAL AR No2 should correspond to the explanation of the NTSC AR "4:3 525line (NTSC, 704x480)", which is indeed included in the help-file. But alas, the explanation of the NTSC AR under question makes it clear that it refers ONLY to DV (?????) capture video, with specific NTSC framesizes: 720x480/704x480 (valid NTSC Full DVD) and 352x240 (valid NTSC VCD).

In other words, contrary to the documentation in its help-file, TMPGEnc NEVER identified an input file to have the PAL AR No3. Instead, input files which (according to the docs) were supposed to be identified as PAL AR No3 they were ALWAYS identified as PAL AR No2 (which is NOT included at all in the docs, but it DOES exist as an option in the Advanced tab).

If anyone has a rational explanation for all this mess, please (please, please ) throw it up on the... table!


That's all for today from me guys... I have already started developing a not that pleasant... headache!

Best regards,

PS1. An interesting point coming up as a side effect of this discusion is that, AR seems to be one thing and the result of the division width/height of a given framesize is another. If you see, for example, the No2 in the above list of ARs, the AR is reported to be the same (4:3) for the framesizes 720x576, 704x576 and 352x288. If we make the division width/height, then although two of them give the same result 1.2222 (704x576 and 352x288), the third one gives a different result, 1.25 (720x576).
Same thing for No4 in the list (352/576=0.6111 and 480/576=0.8333, but they are both reported to have an AR of 4:3).
So, what exactly do we mean when we say Aspect Ratio of an analog video stream? (Thank God we have already thrown out of the window that Pixel Aspect Ratio)

PS2. Now, I've completely developed that... headache

[migf1]

[snip]
i have an avi file that when i run it through gspot, it says that it's 4:3 aspect ratio.
I like my output to be 16:9, cuz I like the widescreen look. i usually set my output to 16:9 AR, but am confused as what to set the input AR as well as the video arrange method, under the advanced tab.

if i set the input AR to 4:3 and the VAM to full screen keep aspect ratio, would the end result come out in letterbox form?
is it bad to set the input AR as 16:9 when it's really not? What should i set the AR and VAM to be if i want the result to be letterbox?

one thing i don't want is to have video that has borders all around it, or borders on the left and right side of the screen.

Hi dafreak,

the way I understand it, you have a 1:1 (VGA) (4:3 in GSpot) source and you want your output to be 16:9. Unless you encode it in DVD format, you cannot achieve a 16:9 output. Even then, it will be rather streched.

If you don't mind the stretching but you don't want to encode it in DVD format, then try the default VCD template, pass "16:9 Display" as the source's AR in the Advanced tab, choose "Full screen (keep aspect ratio)" as VMA and encode it. Don't change the output AR in the Video tab.

You'll end up with a 4:3 output, which will give the illusion of a 16:9 with black borders only on the top and the bottom. It will also be rather streched though.

I think there is no way to convert a 4:3 source into a 16:9 output, with the picture running across the whole width of the screen, without stretching the original source.

Best regards...

[duhmez]

When your source is mpeg, you cant jus divide the top res by the bottom. You only do this when the source is AVI. Mpeg will correct the aspect during playback, this is what the tmpgenc setting, it seta the dar in the file, and adds borders as needed nbased on the setitng you chose.

[reboot]

some good info here.

I have a question along the same lines.

i have an avi file that when i run it through gspot, it says that it's 4:3 aspect ratio.
I like my output to be 16:9, cuz I like the widescreen look. i usually set my output to 16:9 AR, but am confused as what to set the input AR as well as the video arrange method, under the advanced tab.

if i set the input AR to 4:3 and the VAM to full screen keep aspect ratio, would the end result come out in letterbox form?
is it bad to set the input AR as 16:9 when it's really not? What should i set the AR and VAM to be if i want the result to be letterbox?

one thing i don't want is to have video that has borders all around it, or borders on the left and right side of the screen.

You can set the input and output of TMPGEnc any way you want.
Click Load, find the tmpgenc folder, select template, then select Extra, then click on the "unlock.mcf" template.
Now you can select the input AR as 4:3, and output as 16:9 (or any other combination you like).
No matter how you do it, something is going to be stretched, or squashed.
Converting a 4:3 video to 16:9, using the Image Arrangement of "Fullscreen with Aspect Ratio", will give you a finished product that is full screen width, but with "letter boxes" top and bottom (who ever called them letter boxes anyway? They're black bars as far as I'm concerned).
The black bar size will depend on the original AR, and your output AR.

[migf1]

Actually there is no need to load the unlock.mcf template. You can always unlock any TMPGEnc setting you wish, at any time in any template, by right-clicking on the corresponding label and then choosing "Unlock" from the menu that pops up. Just ignore the warning and the setting will get unlocked.

PS. Reboot, I checked the method you suggested but it didn't work for me. The output had vertical left-right black bars, instead of horizontal top-bottom ones.

[migf1]

When your source is mpeg, you cant jus divide the top res by the bottom. You only do this when the source is AVI. Mpeg will correct the aspect during playback, this is what the tmpgenc setting, it seta the dar in the file, and adds borders as needed nbased on the setitng you chose.

Many thanks, duhmez!

[dafreak]

I should have mentioned that i'm converting the avi files to mpeg2 so that i can eventually burn the movies onto dvd.

using the information that was posted by migf1, i set the input media as 1:1 vga because the original avi is 320x240. I set the VMA to full screen, and the output to 16:9. The results are very nice.


Lot of great information here. Thanks a lot guys.

[migf1]

When your source is mpeg, you cant jus divide the top res by the bottom. You only do this when the source is AVI. Mpeg will correct the aspect during playback, this is what the tmpgenc setting, it seta the dar in the file, and adds borders as needed nbased on the setitng you chose.

Many thanks, duhmez!

Hi again duhmez,

what I forgot to ask you yesterday, is this: if I understood you correctly, mpeg files keep the AR info inside them while AVIs don't, right?

Also, is there a program (like GSpot for AVIs) we can use in order to find the AR of a random mpeg file (mpeg files we find on the Net, for example)?

Best regards,

PS1. Btw, does anybody know what exactly is the AR that Media Player Classic shows, in the properties of the files it plays back? It never shows an AR for AVIs, but it always shows an AR for mpeg files. The prob is that when it shows an AR (for mpeg files) most of the times it's a weird one. For example, PAL VCD compliant (4:3) mpeg files created by TMPGEnc are shown having an AR of 176:135 inside Media Player Classic. (??)
Thanks in advance.

PS2. Nice to hear you got the desired results dafreak!

[reboot]

I found that AVICodec will give you pretty good results for mpeg's. (hopefully the code will be linked).

BTW, your 176:135 video is 1.3037:1 (divide 176 by 135), which is darn close to 4:3 (1.3037x3=3.9 and 1x3=3, thus 3.9111:3~4:3), which is not weird at all

Using "Fullscreen with aspect ratio", I have never had black bars on the sides. Using slightly modified (S)VCD templates, one can usually adjust the input aspect to get the desired output.
Lately, I have only been using Mainconcept, as it's much faster (by almost double the speed) of TMPGEnc, and once you get the hang of it's advanced settings, seems more versatile too.

[duhmez]

media player classic is showing the aspect thats in the mpeg. You can put an aspect I sawr with xvid encoder, but its not pollable from an avi container.
AVI container does not suport reorting the aspect een if the video codec can use an aspect flag.

[dafreak]

is the quality output of mainconcept as good as tmpgenc?

[FOO]

There is a simple explanation to all of this.
There is a SAR - sample aspect ratio
There is a DAR - display aspect ratio
pixel aspect ratio is Adobe marketing bullshit probably

You can capture a 720 x 480 video that is 4:3
720 x 480 is NOT 4:3 - the horiz and vert sample rate is different

There is an extra field in the MPEG headers that cause your video to
be displayed different from the SAR.

You can have video at a SAR of 352x480 , 704x480 or 720 x480
and if all theree have a DAR of 4:3 the will look the same

[migf1]

Hi guys, thanks for the new valuable info.

Unfortunately I'm at work right now and I don't have the necessary time to look deeper into it, but a quick search through Google revealed the following rather interesting page:

http://www.mir.com/DMG/aspect.html

It appears that SAR is synonymous to Pixel Aspect Ratio (a common term, not just Adobe's, from what I understood) and DAR is the division: width/height of the pshysical dimensions of the frame (framesize).

I really don't have the time to look deeper into it right now, but I will and I'll post back as soon as I figure out which of those 2 terms TMPGenc uses in its settings [I think "1:1 (VGA)" refers to SAR, while all others refer to DARs.. we'll see].

From a quick reading of the page above I think that all true 4:3 DAR frames should also have a 1:1 SAR. Dunno yet, I really have to read it more carefully when I have some free time (during the weekend, hopefully)

Best regards,

Edit:
PS. Btw, AVICodec shows an AR of 16:9 for all SVCD compliant mpegs (created by TMPGEnc)

[reboot]

Mainconcept's output quality is as good, and sometimes better, than TMPGEnc, and it's faster. It all depends on the settings you use for bitrate, CBR, VBR, multi-pass, whatever.
I found that Mainconcept can do a 2 pass vbr, with settings at max2420, avg2000, min200 (yes 200!) produces a better quality mpeg than TMPGEnc with the same settings, in less than half the time. In the case of a 1 hour avi, about 50 minutes for Mainconcept, and over 2 hours for TMPGEnc at CBR. TMPGEnc 2 pass VBR is over 3 hours.

I just noticed that AVICodec does report all SVCD's at 16:9, and all VCD's at 4:3 WTF?

Without trying to get confusing, TMPGEnc's Video tab shows DAR, whereas it's Advanced tab shows SAR...No?

[duhmez]

The video tab is the dar that is set in the file. the advanced tab aspect is how tmpgenc should barify the video, its prefiltering for encdoing.