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  1. I have tried to rip a DVD with several different encoders in order to compare performance in different formats. I used DVD DECRYPTER to extract the main movie to a single vob file. VLC & Nero players report the original DVD to have an aspect ratio of 720:480. They also report that the extracted vob file has an aspect of 720:480, however GOM Player reports the aspect as 704:480 and plays the VOB file stretched horizontally. I set all three encoders to produce the same size file (600 MB) to keep as many variables constant as possible.

    The first encoder I tried was MeGUI. It slowly produced an amazingly detailed and vivid .mkv This MeGui encoder is amazing. I think the rip looks "better" than the original DVD. If I had an i7 950 computer I wouldn't use anything else. I was able to set the horizontal aspect to 608, but not the vertical. The resulting aspect ratio is 608:416. It looks slightly stretched horizontally and if I'm not mistaken has duplicated an aspect ratio more in line with what GOM player reported for the vob.

    The second encoder I used was Nero Recode. It produced (using 2 passes) an .mp4 file 80x faster than Megu. The video looks a bit fuzzy and flat in contrast and color saturation (compared to the Megu .mkv), but it is certainly not 80x worse. I set the output aspect ratio to 608:416 to match the ratio MeGUI produced, however Nero Recode recommended that for 604 the vertical should be 464. That I don't understand! In any case the resulting video does have an aspect of 608:416, plays with some pillarboxing and does not looked stretched horizontally (as does the MeGUI .mkv).

    Finally I tried AGK. I was only able to set the horizontal as 608. The resulting .avi (xvid) video is 608:464. It plays rather stretched in the vertical. I was surprised that there wasn't as much difference between the Nero Recode .mp4 and the .avi. The .avi looks a bit sharper and does better with motion. The .mp4 looks more vivid. Compared to the MeGUI .mkv both really suffer in comparison! I found AGK to be about 15X faster than MeGUI on my system.

    It was an interesting experiment but I don't understand the aspect output from AGK or MeGUI. Or the suggestion to set the aspect to 608:464 in Nero. Given that my various players report a different aspect ratios for the original vob file I wonder if that is the problem, or have I made a mistake setting up the encoders? If I open the vob in Videoredo and look at the properties it says the display size is 720x480 and that the aspect ratio is 4:3. How does that work? Shouldn't my output rips "look" like they have the same proportions as the original dvd? And if that is true, how do I get the encoders to cooperate?
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  2. I'm a MEGA Super Moderator Baldrick's Avatar
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    Open the dvd with mediainfo and see what it says about the display aspect ratio.

    The DVD Display Aspect Ratio is 16:9 or 4:3, nothing else. So they/you should resize to such a resolution(like 640x480 4:3 or 640x360 16:9 or 640x292 16:9 with black borders cropped, etc) OR you can also resize to any size you want and set the Display Aspect Ratio in the mkv,mp4 and the player should resize for you(not all players supports this).

    608x464 is correct if your source is 4:3.

    What is your dvd source? A commercial dvd?
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  3. Thanks Baldrick!

    It's starting to make sense....

    I used Mediainfo and it gives the display aspect ratio of 4:3 and the video is 720x480.
    When I play the extracted vob file in GOM Player it seems not able to automatically recognize the need to show the video as 4:3. When I set it manually to 4:3 in the player it looks correct.

    So let me see if I understand this now. Both Nero Recode and AGK resized the video to a ratio of 4:3 (or 608 x 464) and also set a flag to display at 4:3. Since GOM Player seems to ignore the display aspect flag the videos still look correct because the video itself has the correct ratio and the flag doesn't matter. Not so in the case of the MeGUI encode. MeGUI seems to keep the input video ratio (720 x 480 to 608 x 416) and relies on the 4:3 display aspect inbedded in the video. Since GOM Player ignores the flag the video looks distorted horizontally until GOM is manually told to display in 4:3. Am I understanding this correctly?

    That leads me to ask if MeGUI has an advantage in encoding this way since the video size is around 11% smaller?
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  4. DAR = SAR * PAR

    DAR = Display Aspect Ratio, the final shape of the picture
    SAR = Storage Aspect Ratio, the frame size
    PAR = Pixel Aspect Ratio, the shape of individual pixels

    Some players do not respect PAR or DAR flags. They simply display at the SAR (ie, they assume square pixels).
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