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  1. Member
    Join Date: Jan 2004
    Location: United States
    Search Comp PM
    I need to convert AVCHD footage from 1080i (29.97fps) to 540P. I'm looking at a tool called StaxRip. Need to frame serve from Sony Vegas. Video needs to be deinterlaced and obviously resized. My goal is best quality, lowest bitrate, and I don't care about how long it takes to encode. Suggestions for a good workflow?
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  2. Member
    Join Date: Oct 2004
    Location: Freedonia
    Search Comp PM
    Why 540P? Do you have a better reason than you just cut the number 1080 in half? What's your plan for the final product? 540p isn't valid for DVD or BD, should you care to use those.

    It's impossible to answer questions about what bitrate you should use. For example, if I ask you what your favorite fruit is and you say "Strawberry" and your best friend gets asked the same question and he says "Cherry" is one of you right and the other wrong? The bitrate you should use is whatever YOU and NOBODY ELSE is pleased with for a final result. There's too much individual taste here to have hard and fast rules. I had a friend some years ago who was very happy to record over the air TV with horrible snow and other video defects and on top of that he saved it to VCD, which has low bitrates to work with. I'd guess that 99% of the people here would describe his captures as "Not worth saving" and "For single view ONLY if no other option available", yet he kept them and was happy with them. I have no idea how picky you are so if you just want a wild guess, since you don't say what codec you will be using, I'd say start with 4000 Kbps and go up or down as you wish from there (go up to a higher number if you don't like the quality, go down if you do like the quality).

    I can't advise on your workflow. I don't use StaxRip or Vegas.
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  3. Member
    Join Date: Jan 2004
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    Search Comp PM
    I'm looking at this guide:
    http://birds-are-nice.me/publications/extremex264_1.shtml
    But my source is 1080i so it needs to be deinterlaced, and resized. I read somewhere that it's easy to go from 1080i to 540p as you are just discarding one field. The purpose of the video is not for DVD, nor blu-ray. It's for downloadable video, but the content is rather long so I want to get the lowest file size.
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  4. Originally Posted by sdsumike619 View Post
    I read somewhere that it's easy to go from 1080i to 540p as you are just discarding one field
    Yes, that's easy. And it looks like crap. Best quality for real interlaced video would be QTMGC() and resize. For telecined film TFM().TDecimate() and resize.

    Originally Posted by sdsumike619 View Post
    I hope you never try to play them on a Blu-ray player or set-top media player.
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  5. Originally Posted by sdsumike619 View Post
    My goal is best quality, lowest bitrate...
    You know that makes no sense, don't you? Make CRF encodes for the highest number you can stand and then be done with it and make the rest at that same number (if there are more). Do some tests to see if it's 24, 30, 50, what?
    But my source is 1080i so it needs to be deinterlaced
    The fact that it's 1080i does not necessarily mean it has to be or should be deinterlaced. If you don't know how to tell what the content is like beyond just noting that there's a 'i' in it, post a small sample.
    ...so I want to get the lowest file size.
    No you don't. The lowest file size will be unwatchable.
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  6. Member
    Join Date: Jan 2004
    Location: United States
    Search Comp PM
    Yes. Agree about QTGMC, this is the tutorial I am following, or trying to follow at the moment:
    http://www.bubblevision.com/underwater-video/Vegas-YouTube-Vimeo.htm but I'm more interested in the settings in this guide http://birds-are-nice.me/publications/extremex264_1.shtml because the bubblevision guide doesn't care about file size.
    Last edited by sdsumike619; 18th May 2014 at 19:59.
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  7. About that quest for best quality while having smaller size.
    You can start this task using 2pass VBR and you decide what filesize should be about right. This will get you average bitrate (using bitrate calucator of some sort) and you encode 2pass VBR then using that average bitrate. You watch the video and say, hmmm , I wonder if lowering bitrate a bit would be still ok, wait, how much ? etc, etc, you can spend couple of days encoding trying figuring out what is the best for you.

    That is why you strat with CRF, using encoder that allows that, you resize to 960x540, deinterlace, even using double frame rate mind you, 60i to 60p, not 60i to 30p, it is for download and video is smooth, double fps will give you 20% more bitrate not double). So then you encode CRF 18. You get filesize. You say this is too much. OK. You encode CRF19. In the meantime checking quality, you can just encode 20seconds of video with that CRF 19, because CRF means it keeps quality at all times. Quality is good you encode it all and check filesize. After this two encodings you already know at what rate filesize decreases by increasing that CRF value and you also have a pretty good idea how video might look by increasing CRF by 1. So everything make sense a bit, Not with 2pass VBR much. Get used to that CRF, get rid of 2pass VBR.

    Another thing, using this CRF, you have to limit buffers a bit, look into it, for 540p set them to about 15.000 or 20.000 in those encoding softwares (--vbv-bufsize 15000 --vbv-maxrate 15000), so it does not exceed bitrate into extreme limits especially if using smaller CRF. After first encode use bitrate viewer and you will see bitrate distribution, you will know more what your high bitrates are and you can adjust those buffer limits.

    Forget 2pass VBR and you get it far ...
    Those numbers may vary, because your video could be whatever, I put something down just to explain it ...
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  8. Member Cornucopia's Avatar
    Join Date: Oct 2001
    Location: Deep in the Heart of Texas
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    @_Al_, dissing 2passVBR in favor of CRF/CQ is overly simplistic at best and downright bad info at worst. For people who have filesize or bandwidth requirements (e.g. CD/DVD/BD storage/playback, download streaming), 2passVBR is likely the best choice, for those who need a certain quality and are willing to take whatever filesize/bitrate it comes out at (e.g. HTPC HDD storage/playback), CRF/CQ is the best choice. They both are deterministic and both very useful, but take different paths to get to similar places.

    Scott
    "When will the rhetorical questions end?!" - George Carlin
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  9. Member
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    Location: Freedonia
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    Originally Posted by sdsumike619 View Post
    I'm looking at this guide:
    http://birds-are-nice.me/publications/extremex264_1.shtml
    But my source is 1080i so it needs to be deinterlaced, and resized. I read somewhere that it's easy to go from 1080i to 540p as you are just discarding one field. The purpose of the video is not for DVD, nor blu-ray. It's for downloadable video, but the content is rather long so I want to get the lowest file size.
    Why? Why why why why why?

    You have over 1600 posts here and have been a member for about 10 years now and you suddenly think some bizarre random website with a POS guide is your complete source of truth now? You know you could have just read the guides here or asked. The style of that guide is awful. I gave up trying to read it after looking at the 2nd section. To be honest with you, I'm not interested in helping any more because you keep finding bizarre places to teach you. If those other guides are so great, why do you need help? (Hint - Maybe you need help because they aren't so great.) You sure do have an awful lot of posts and have been here a really long time to be suddenly acting like a clueless newbie who knows absolutely nothing about video. I've got better things to do than waste time on this.
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  10. Originally Posted by Cornucopia View Post
    @_Al_, dissing 2passVBR in favor of CRF/CQ is overly simplistic at best and downright bad info at worst. For people who have filesize or bandwidth requirements (e.g. CD/DVD/BD storage/playback, download streaming), 2passVBR is likely the best choice, for those who need a certain quality and are willing to take whatever filesize/bitrate it comes out at (e.g. HTPC HDD storage/playback), CRF/CQ is the best choice. They both are deterministic and both very useful, but take different paths to get to similar places.

    Scott
    yes, but too many times someone is looking for magical balance, quality/bitrate and with 2pass VBR it is tedious work to achieve, for somene who needs to orient himself where it stands (distributed bitrate, quality, volume) needs to give it a try with CRF

    for limited bandwith , one can use CRF also, for example 1000Mbit stream, after some resize to SD resolution,
    x264 --crf 18 --profile baseline --level 3.0 --ref 1 --vbv-bufsize 1100 --vbv-maxrate 1000
    where those buffer settings keep bitrate down to desired limit, and lower CRF keeps bitrated distribution always up to the bandwith limit if needed

    To max out limited space like BD , DVD, sure you have to go with 2pass VBR.
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  11. Member
    Join Date: Jan 2004
    Location: United States
    Search Comp PM
    I think I got a handle on it. Did a bunch of reading last night and it seems the best route with x264 is to pick a CRF that suits you for the quality, and then encode using an x264 preset such as slow, etc to get the file size down, which will increase encoding time. That's the route I'm going to go, high quality CRF setting, with one of the slower presets.
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  12. If you look at file sizes with different presets you'll see there are big differences between ultrafast, superfast, and veryfast. But there's not much difference from veryfast through placebo -- typically 5 to 10 percent. Visual quality increases a bit between veryfast and placebo. You get less posterization and smoother edges on moving objects.
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  13. Member
    Join Date: Jan 2004
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    Originally Posted by jman98 View Post
    Originally Posted by sdsumike619 View Post
    I'm looking at this guide:
    http://birds-are-nice.me/publications/extremex264_1.shtml
    But my source is 1080i so it needs to be deinterlaced, and resized. I read somewhere that it's easy to go from 1080i to 540p as you are just discarding one field. The purpose of the video is not for DVD, nor blu-ray. It's for downloadable video, but the content is rather long so I want to get the lowest file size.
    Why? Why why why why why?

    You have over 1600 posts here and have been a member for about 10 years now and you suddenly think some bizarre random website with a POS guide is your complete source of truth now? You know you could have just read the guides here or asked. The style of that guide is awful. I gave up trying to read it after looking at the 2nd section. To be honest with you, I'm not interested in helping any more because you keep finding bizarre places to teach you. If those other guides are so great, why do you need help? (Hint - Maybe you need help because they aren't so great.) You sure do have an awful lot of posts and have been here a really long time to be suddenly acting like a clueless newbie who knows absolutely nothing about video. I've got better things to do than waste time on this.
    Well I am a newbie when it comes to all this command line stuff and trying to get high quality (or I should say maintain high quality since my source is already high quality) and getting the file size down as much as possible. Prior to this, the vast majority of my work has been DVD related. So yes, I'm still struggling with this current goal. I think the bubblevision tutorial is the best, I just need to tweak some settings to get the file size down. Consensus on all the forums seems to be that QTGMC is the best deinterlacer, and deinterlacing appears to be where quality can be lost.
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  14. Originally Posted by sdsumike619 View Post
    Consensus on all the forums seems to be that QTGMC is the best deinterlacer, and deinterlacing appears to be where quality can be lost.
    Yes, but most movies and television shows (shot of film) are telecined, not interlaced. They should be inverse telecined back to film frames (23.976 fps). Truly interlaced material is mostly limited to live sports, news, and a few TV shows.
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  15. Member
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    The footage is mine, filmed by me on my Canon XA10, 1080i 29.97fps
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  16. Member Cornucopia's Avatar
    Join Date: Oct 2001
    Location: Deep in the Heart of Texas
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    I still don't get why you think it needs to be deinterlaced. What is the target (usage & devices) for this footage?

    Scott
    "When will the rhetorical questions end?!" - George Carlin
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  17. It is meant for download, so with downscaling it to 1280x720 or 960x540 etc. and deinterlacing to double frame rate would give nice results.

    Bandwidth is an issue also. Always is with this kind of service. To upload full 1920x1080i needs much higher bitrates and of course interlace could be issue trying to play it back on devices. Double frame rate could be technically problem also , but with downscaling the video, it is kind of eliminated. One just need to encode modest settings for x264 encoder, like default preset, , low ref. freames. It should be playable on all devices. Or to generate high and low quality streams is a possibility too, I'm sure op has this sorted out already. High quality download streams can generate too much bandwith also. Or the solution could be just download video on some public servers, storage places, with all negative problems that go with it.
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  18. Originally Posted by _Al_ View Post
    downscaling it to 1280x720 or 960x540 etc. and deinterlacing to double frame rate would give nice results.
    In the opposite order, of course.
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  19. yes, yadif bob I found to be sufficient for HD sources (for interlace SD footage, QTGMC is a must on the other hand, there is a severe lack of resolution) ,but if one has a plenty of time for encoding why not to make it tip top, to reduce "stair" effect on horizontal lines as much as possible ... also it depends on footage, if it is a nature shot, yadif bob should be fine, but for indoor footages with lots of straight lines with panning, etc., QTGMC might make sense ...
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  20. btw. yadifmod might be also worth a look
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