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  1. Member Lathe's Avatar
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    I don't know if I have used the word 'Transcoding' accurately, but this is what I THOUGHT I had to do because I had one of my Blu-ray encodes that had been done by my friend at level 4.1 which was fine, but it had been set at 12 ref frames. The MKV size is about 6 Gigs and has an average bitrate of about 6300. Okay, well I'm thinking that before I burn a DVD DL, since I'm concerned about my OPPO BDP-83 maybe not being able to play back such a high ref frame rate that I should use UncropMKV and re-encode primarily to lower the ref frames to 3 (default for UncropMKV) And, I could also have the extra benefit of having a proper AR (as I asked about in my last thread) since this ALSO has another squirrelly encode that is cropped at 2.35:1. Just so you know, the AR of the original file is 1280x544 and the AR of the Uncropped MKV is 1280x720 (as it should be...)

    What was really weird (probably just because I am ignorant ) is that the resulting MKV file was HALF the size of the original! Now, I have used UncropMKV several times and usually I've only noticed a slight decrease in file size. So, now the Uncropped MKV is just under 3 Gigs BUT amazingly has an average bitrate of 6000!

    I am COMPLETELY mystified as to why this is so. I THINK the only real difference is that the re-encode has only 3 ref frames instead of 12. If you wouldn't mind, could someone please explain the mechanics of exactly WHY this is so? Like I say, my ignorant first response is that I cannot see how the file can be bloody HALF the size with almost the same bitrate...??? All of the re-encodes that I have done with UncropMKV have turned out beautifully and looked great on my 50" plasma, and to the naked (and inexperienced) eye, both files look pretty much the same (it is a visually simple Korean film called 'THE THIEVES' with some action, but no flashy or fanciful visuals) BUT, this is the first time there has been such a disparity in file sizes.

    I appreciate any enlightenment that you could give me.

    Thank you!
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  2. Originally Posted by Lathe View Post
    And, I could also have the extra benefit of having a proper AR (as I asked about in my last thread) since this ALSO has another squirrelly encode that is cropped at 2.35:1. Just so you know, the AR of the original file is 1280x544 and the AR of the Uncropped MKV is 1280x720 (as it should be...)
    I didn't understand all that. Did you say it's 1280x720 with the black bars added back in? It is a 2.35:1 film:

    http://www.imdb.com/title/tt2330866/technical?ref_=tt_dt_spec

    I appreciate any enlightenment that you could give me.
    Since file size is entirely a function of length and bitrate, at least one piece of information you've provided is incorrect. File size has nothing at all to do with the number of reference frames or the resolution or anything else - only bitrate and running time.

    If I had to guess, I'd say the bitrates you provided are incorrect, one of them anyway. How did you derive them? Either that or one of the films is truncated.
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  3. Member Lathe's Avatar
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    Originally Posted by manono View Post
    Originally Posted by Lathe View Post
    And, I could also have the extra benefit of having a proper AR (as I asked about in my last thread) since this ALSO has another squirrelly encode that is cropped at 2.35:1. Just so you know, the AR of the original file is 1280x544 and the AR of the Uncropped MKV is 1280x720 (as it should be...)
    I didn't understand all that. Did you say it's 1280x720 with the black bars added back in? It is a 2.35:1 film:

    http://www.imdb.com/title/tt2330866/technical?ref_=tt_dt_spec

    I appreciate any enlightenment that you could give me.
    Since file size is entirely a function of length and bitrate, at least one piece of information you've provided is incorrect. File size has nothing at all to do with the number of reference frames or the resolution or anything else - only bitrate and running time.

    If I had to guess, I'd say the bitrates you provided are incorrect, one of them anyway. How did you derive them? Either that or one of the films is truncated.
    Thank you for your reply...

    Yes, what you said about the AR is correct. My friend had encoded the blu-ray WITHOUT the black bars, thus the odd AR. After running Uncrop (heh, which is why it is called that ) then, with the black bars re-encoded back in as they SHOULD be, the AR is now with the correct AR inside them and when with the black bars added it NOW has a full 16x9 for Blu-ray structure so that a stand alone player will play it back properly.

    And, as to your 2nd comment, I went back and re-checked and YES you are right! I hadn't actually checked the Uncropped file in detail, but you are exactly right! For some odd reason and I hadn't realized this, after running it through UncropMKV the file IS truncated!

    NOW, my question is WHY the hell didn't UncropMKV finish the whole file....???!

    This just gets weirder and weirder...

    I appreciate though because of your knowledge and experience you noticed that right away. NO WONDER the file size is half! DUHHHH! Now I hafta figure out WHAT the heck is happening...
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  4. Originally Posted by Lathe View Post
    NOW, my question is WHY the hell didn't UncropMKV finish the whole file....???!
    Dunno, never used that program. Rather than encode it twice (once cropping it and then again adding back the black) just go back and have your 'friend' redo it, this time without cropping the black bars.
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  5. Member Lathe's Avatar
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    Heh, yeah, I know, I know... But, what's done is done already. Sure is weird though that UncropMKV all of the sudden just up and started truncating the MKVs, basically not finishing them.

    What I may hafta do with that one film because the frame rate is so high is just leave it as an MKV file and HOPEFULLY it will play. I'll hafta check it and see.

    Another file that UncropMKV did that too was an HD capture of 'CHERRY 2000' (it is not available on Blu-ray) The thing was showing a variable frame rate, so when I went to use TSMuxer the sync was off; I tried the most common frame rates with TSMuxer 23.xxx and 29.xxx but the sync was WAY off. So, I tried the mother program of UncropMKV called MultiAVCHD and I noticed that when I loaded it, it showed a frame rate of 25, which is unusual. So, I went back to TSMuxer and input the 25 frame rate and THAT got it! So, I did get that one to burn and play as an AVCHD disc which was nice.

    Thanks again for the help!

    If someone has a clue as to WHY unCropMKV is suddenly not finishing the MKV files, please by all means let me know. Doesn't look like there's been any updates to it in 2 years and there is no current forum anymore, so...

    Appreciate it!
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  6. Member netmask56's Avatar
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    How about posting a MediaInfo file of the file (view TEXT)?
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  7. Member Lathe's Avatar
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    Originally Posted by netmask56 View Post
    How about posting a MediaInfo file of the file (view TEXT)?
    I appreciate your reply, but the Media Info file for both the original MKV file and the Uncropped truncated one are identical with the exception of the AR and the size since only about 1/2 of it is there

    However, for what it's worth, I just now burned 'THE THIEVES' as an MKV, and even at 12 ref frames I was quite surprised that my OPPO Blu-ray player plays it beautifully!

    So, even though this thread has kind of morphed from what I originally asked, my only CURRENT mystery is why UncropMKV is only rendering about 1/2 of the files the last few times I've used it...

    To be accurate and honest, I think I'll start another thread about that which will be specific to that. But, thank you all VERY much for all your help!

    Cheers!
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  8. Use Mkvmerge.
    After you add file highlight or select MPEG-4, then select the format specific options.
    Change the NALU size to 4. Start muxing. Take the new file and use uncrop.
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  9. Member Lathe's Avatar
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    Originally Posted by Riven123 View Post
    Use Mkvmerge.
    After you add file highlight or select MPEG-4, then select the format specific options.
    Change the NALU size to 4. Start muxing. Take the new file and use uncrop.
    Thank you kindly for replying to this post after all this time!

    I think I figured later on that when this happened, UncropMKV had not processed the entire file for some reason.

    However, I find your suggestion interesting; what exactly is that changing, just so I will know.

    Thanks!
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  10. I'm a Super Moderator johns0's Avatar
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    If you move the seeking bar to see any other part of the video uncropmkv will use that encode to that point that you moved it to.
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  11. Member Lathe's Avatar
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    Originally Posted by johns0 View Post
    If you move the seeking bar to see any other part of the video uncropmkv will use that encode to that point that you moved it to.
    Oh, that's right; I remember now, thanks!
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