VideoHelp Forum
+ Reply to Thread
Results 1 to 9 of 9
Thread
  1. Member
    Join Date
    Sep 2008
    Location
    United States
    Search Comp PM
    I've been trying to do a lot of Decoding 720p x264 mkv's into SD mkv. A lot of them have ar's like 2.35. Anyway, i'm kind of lost on how to get a good resolution with out messing up the AR to much. For example i used 788 x 352 and i know that makes 2.23, but would that be an okay resolution for a film with that AR? I'm looking to get bigger resolutions with out makin it a bad encode. So what i'm asking is what should i be doing. I've read up on stuff, but let's face it i'm so bad at math i don't under 90% of what the charts and stuff tell me.


    Also, is there anyway to downmix aac audio etc to 2.0 with out making MeGui crash? I've been forced to use the original channels on must of my encodes because it won't let me down mix. So i'm stuck with a 5.1 aac track with a 257 bitrate haha


    Anyway, i'm sure people will just google is your friend etc, but if you wanna help a slow person out. This could be your good deed for the month.

    Also, does anyone know of a better program to for what i'm doing? One that will still help me calculate the bitrate etc like MeGui does for me so i can pretty much guess the file size.
    Last edited by kkiller23; 19th Jun 2012 at 05:21.
    Quote Quote  
  2. Originally Posted by kkiller23 View Post
    I've been trying to do a lot of Decoding 720p x264 mkv's into SD mkv. A lot of them have ar's like 2.35. Anyway, i'm kind of lost on how to get a good resolution with out messing up the AR to much. For example i used 788 x 352 and i know that makes 2.23, but would that be an okay resolution for a film with that AR?
    Sticking with mod 16 frame sizes will give you better compression, efficiency, and compatibility. So using 784x352 would be better than 788x352.

    In most cases it doesn't matter for MKV files, but with Divx/Xvid AVI files you need to keep the horizontal resolution below 720 if you want Divx certified DVD players to play it (you won't be playing MKV files on such a player).
    Quote Quote  
  3. Member
    Join Date
    Sep 2008
    Location
    United States
    Search Comp PM
    So 784 x 336 would be a good resolution? So picking something over 720 just means it won't work on DivX DVD players?
    Quote Quote  
  4. Originally Posted by kkiller23 View Post
    So 784 x 336 would be a good resolution?
    784 (an integer multiple of 16) would be better than 788 for the width, for the reasons stated.

    Originally Posted by kkiller23 View Post
    So picking something over 720 just means it won't work on DivX DVD players?
    Divx DVD players don't play MKV files at all. That's why I said it may not matter in this case. It will depend on what your intended (and future) playback device supports.
    Quote Quote  
  5. Member
    Join Date
    Sep 2008
    Location
    United States
    Search Comp PM
    But over 784 x 336 is fine for something with a source 2.35:1 DAR? So when picking a resolution all i have to do it get it as close as the original DAR as possible, correct? or am i missing something. Let's say the source is 2.35:1 and i pick a resolution that comes out to "2" when i divide height and width. Would that still be a good DAR for that source or should i stick to trying to get as close as possible as source and forget wanting a higher resolution?
    Quote Quote  
  6. Originally Posted by kkiller23 View Post
    But over 784 x 336 is fine for something with a source 2.35:1 DAR?
    How accurate you want to be is up to you. I think it's close enough. You wouldn't be able to tell the difference on the TV without using a ruler.

    Originally Posted by kkiller23 View Post
    So when picking a resolution all i have to do it get it as close as the original DAR as possible, correct?
    Again, it's up to you how accurate you want to be.


    Originally Posted by kkiller23 View Post
    Let's say the source is 2.35:1 and i pick a resolution that comes out to "2" when i divide height and width. Would that still be a good DAR for that source or should i stick to trying to get as close as possible as source and forget wanting a higher resolution?
    Once again, it's up to you. I think a ~17 percent error is too large. I try to stay within a percent or two.
    Quote Quote  
  7. Member
    Join Date
    Sep 2008
    Location
    United States
    Search Comp PM
    I have the correct idea of what i'm doing though, right? I just wanna make sure i'm doing it right before i start doing it to other mkv's.
    Last edited by kkiller23; 19th Jun 2012 at 15:52.
    Quote Quote  
  8. Yes, you have the right idea. With square pixel encoding the frame width divided by the frame height is the aspect ratio.
    Quote Quote  
  9. Member
    Join Date
    Sep 2008
    Location
    United States
    Search Comp PM
    Alright thank you for the help. I'm not sure if i should start another thread for this, but when i downmix 5.1 audio to 2.0 with megui to aac i'm getting a lot of popping sounds when the volume is loud. Does anyone know how to fix this?
    Quote Quote  



Similar Threads

Visit our sponsor! Try DVDFab and backup Blu-rays!