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  1. Member
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    Is there a specific bitrate to attain true 720p or 1080p? I'm new to BR ripping and figure just because a movies dimensions are 1920x1080 or 1280x720 doesnt necessarily make it 1080p or 720p... or even HD for that matter. Doesnt there have to be a minimum bitrate? For example, say I have a 2hr movie I just ripped from BluRay and use h264 to encode to mkv, mp4, whatever. What would I have to make the minimum bitrate to achieve 1080p quality?
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  2. Originally Posted by smackyourfupa View Post
    Is there a specific bitrate to attain true 720p or 1080p?
    No.
    ...just because a movies dimensions are 1920x1080 or 1280x720 doesnt necessarily make it 1080p or 720p... or even HD for that matter.
    Yes it does. Although if it's been upscaled from standard def, it's just upscaled standard def. But by definition, 720p and 1080 i or p are high def.
    Doesnt there have to be a minimum bitrate?
    No.
    What would I have to make the minimum bitrate to achieve 1080p quality?
    There is no 1080p quality. You chose the bitrate to achieve the filesize you want. Or, better, do a quality-based encode to achieve the quality you want.
    Last edited by manono; 15th Mar 2011 at 07:17.
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  3. Look at the bitrates of the videos in this post:

    http://forum.videohelp.com/threads/295672-A-problem-for-video-experts?p=1811057&viewfu...=1#post1811057

    They are standard definition and Xvid but the issue is the same: Different videos require different amounts of bitrate to maintain quality.
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  4. Member edDV's Avatar
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    If you are looking for commercial Blu-Ray "1080p" quality, you wouldn't re-encode at all. They have already compressed the snot out of it from their master. If you re-encode, you will be lowering quality further.

    If you think HDTV has adequate quality, their typical MPeg2 bitrates are ~16Mb/s for 1080i and ~12Mb/s for 720p. For h.264 use ~70% those rates.
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    Originally Posted by edDV View Post
    If you are looking for commercial Blu-Ray "1080p" quality, you wouldn't re-encode at all. They have already compressed the snot out of it from their master. If you re-encode, you will be lowering quality further.

    If you think HDTV has adequate quality, their typical MPeg2 bitrates are ~16Mb/s for 1080i and ~12Mb/s for 720p. For h.264 use ~70% those rates.
    After ripping a BR disc 20-40 GB is way too large so I'm basically asking whats the max bitrate you can use to re-encode and still maintain HD quality.
    I have alot of m2ts files that are obviously BR rips that are under 4GB 1080p AC3 audio that are between 4000 and 5000 kbps and they look close to BR on my Panasonic 50".
    Last edited by smackyourfupa; 15th Mar 2011 at 13:09.
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  6. aBigMeanie aedipuss's Avatar
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    Originally Posted by smackyourfupa View Post
    Originally Posted by edDV View Post
    If you are looking for commercial Blu-Ray "1080p" quality, you wouldn't re-encode at all. They have already compressed the snot out of it from their master. If you re-encode, you will be lowering quality further.

    If you think HDTV has adequate quality, their typical MPeg2 bitrates are ~16Mb/s for 1080i and ~12Mb/s for 720p. For h.264 use ~70% those rates.
    After ripping a BR disc 20-40 GB is way too large so I'm basically asking whats the max bitrate you can use to re-encode and still maintain HD quality.
    did you mean to say min bit rate?

    most people adjust the bitrate to fit the media they want it on. dvd-r, dvd-dl, bd-r. what's your output going on? if to hard disc the choice is up to you. anything from 50mbps to 1mbps is possible. it's your eyes watching on your display, find what works for you.
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  7. Mod Neophyte Super Moderator redwudz's Avatar
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    I took a quick look at one of my RipBot BD>MKV (H.264) two pass conversions at 1920 X 1080 and it was about 11.2Mbps at ~8Gb size on a one and a half hour movie, and IMO, the quality is quite good for it's size. I size them to fit on a DVD DL disc for backup.

    One of the SD DVD>MKV conversions I did with HandBrake came out at 1229Kbps for about a 1.2GB size on a two hour movie and it looks very close to the original for quality.

    Those sizes and bitrates only relate to those particular movies. The amount of action in a video, the lighting and the length, along with other factors, all determine the 'best' bitrate for video to achieve the desired quality.
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    Originally Posted by aedipuss View Post

    did you mean to say min bit rate?

    most people adjust the bitrate to fit the media they want it on. dvd-r, dvd-dl, bd-r. what's your output going on? if to hard disc the choice is up to you. anything from 50mbps to 1mbps is possible. it's your eyes watching on your display, find what works for you.
    Yes, I meant min bitrate. Output is going to had drives. So technically, there is no minimum bitrate to achieve HD quality?
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  9. Member edDV's Avatar
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    Originally Posted by smackyourfupa View Post
    Originally Posted by aedipuss View Post

    did you mean to say min bit rate?

    most people adjust the bitrate to fit the media they want it on. dvd-r, dvd-dl, bd-r. what's your output going on? if to hard disc the choice is up to you. anything from 50mbps to 1mbps is possible. it's your eyes watching on your display, find what works for you.
    Yes, I meant min bitrate. Output is going to had drives. So technically, there is no minimum bitrate to achieve HD quality?
    Quality results from both resolution and bit rate. If you hold resolution and decrease bit rate, compression artifacts will increase. The amount of artifacts depends on the quality of the source (e.g. noise, transfer quality), the exposure and amount of motion in the material.

    1080p video can look like crap and still be 1080p.

    The industry regards "HD" as anything that exceeds DVD resolution. "Quality" is a separate issue from resolution.
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    as has been said before, 720p and 1080p are simply resolutions (1280 x 720) or 1920 x 1080)
    No matter how low/high the bitrate, they can still be called "HD".

    The reason some "HD" looks good and some looks very soft/blocky/etc. depends on the bitrate chosen and whether it is appropriate for the source.

    A solid black background with someone talking is going to require less bitrate than a busy street scene because there is less movement from frame to frame in the first scenario. Digital video compression works by taking frames of video at set intervals and just tracking the differences from frame A to frame B. Lots of motions, lots of bitrate required..little motion..little bitrate required.

    So the bitrate requirements from one movie to the next (or even from one scene to the next in the same movie) could vary wildly.

    So..without a "standard"..what's a guy to do? I prefer using constant quality settings in my applications. It creates a variable bitrate file that gives it all it needs in the fast action and throttles it down in the slower/less complex scenes.
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  11. I agree with greymalkin. Use constant quality encoding and you always get the quality you want. Let the bitrate fall where it may.
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    Originally Posted by smackyourfupa View Post
    I have alot of m2ts files that are obviously BR rips that are under 4GB 1080p AC3 audio that are between 4000 and 5000 kbps and they look close to BR on my Panasonic 50".
    i have to be honest with you, if you can look at a 4-5 mbps 1080p re-encode of a blu-ray on a 50" hdtv and you think it looks close to the original BD then perhaps you either need a better quality tv, to adjust your tv or get some cataract surgery ASAP.

    if the BD could have been encoded at 4-5 mbps to begin with, and the authoring house is starting with mastering quality source, then they wouldn't have bothered to encode at 25-35 mbps to begin with.

    there seems to be this ridiculous notion that permeates the "back up" community that you can drop the bit rate to the absolute bare minimum and somehow retain almost all the original quality. this mind set has a second component in that the caveat is that the video codec used must be x264, somehow the imbeciles that create these back ups are convinced that a free open source h264 encoder is so vastly superior to the commercial 70 thousand dollar commercial grade h264 encoder that you can use 1/8 the bit rate and achieve the same results.

    do yourself a favor, if you are intent on "fair use backing up" a BD rip and you wish to stick with 4-5 mbps, go down to 1280x720p, use 5 mbps, use one of the slower presets in 2 pass mode and crank up the various quality settings.
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    well..looking back over the thread the fact that he's got a bunch of BD Rips and he doesn't know how to encode something to that size tells me "Fair Use" has nothing to do with it

    can we rename the topic to "How do I get my actual BluRay backups to look just like the pirated ones I downloaded?"
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    Originally Posted by greymalkin View Post
    well..looking back over the thread the fact that he's got a bunch of BD Rips and he doesn't know how to encode something to that size tells me "Fair Use" has nothing to do with it

    can we rename the topic to "How do I get my actual BluRay backups to look just like the pirated ones I downloaded?"
    i was trying to be "nice", anytime i see someone ask how to "back up" a BD (or dvd for that matter) and it involves something other than burning an exact copy i automatically conclude that piracy rears it's head somewhere in the work flow pipeline.

    of course, considering my views on copyright laws and the fact that perhaps at certain times in my life i may have engaged in activities that in some countries may or may not be misconstrued as copyright violations, i am not so quick to denounce anyone else's activities, it just annoys me to no end when people seem to think they can take a commercially authored and pressed 35 mbps BD and re-encode it at the same resolution @ 4-5 mbps and make a near transparent copy of the original.
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    Originally Posted by deadrats View Post
    Originally Posted by smackyourfupa View Post
    I have alot of m2ts files that are obviously BR rips that are under 4GB 1080p AC3 audio that are between 4000 and 5000 kbps and they look close to BR on my Panasonic 50".
    i have to be honest with you, if you can look at a 4-5 mbps 1080p re-encode of a blu-ray on a 50" hdtv and you think it looks close to the original BD then perhaps you either need a better quality tv, to adjust your tv or get some cataract surgery ASAP.

    if the BD could have been encoded at 4-5 mbps to begin with, and the authoring house is starting with mastering quality source, then they wouldn't have bothered to encode at 25-35 mbps to begin with.

    there seems to be this ridiculous notion that permeates the "back up" community that you can drop the bit rate to the absolute bare minimum and somehow retain almost all the original quality. this mind set has a second component in that the caveat is that the video codec used must be x264, somehow the imbeciles that create these back ups are convinced that a free open source h264 encoder is so vastly superior to the commercial 70 thousand dollar commercial grade h264 encoder that you can use 1/8 the bit rate and achieve the same results.

    do yourself a favor, if you are intent on "fair use backing up" a BD rip and you wish to stick with 4-5 mbps, go down to 1280x720p, use 5 mbps, use one of the slower presets in 2 pass mode and crank up the various quality settings.
    Isnt h264 a higher quality encoding method than the method they use to encode blu-rays like vc-1 or mpeg 2? Wouldnt that explain how such a small h264 encoded file can come to in comparison to a 25-30gb blu ray?
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    Originally Posted by deadrats View Post
    Originally Posted by greymalkin View Post
    well..looking back over the thread the fact that he's got a bunch of BD Rips and he doesn't know how to encode something to that size tells me "Fair Use" has nothing to do with it

    can we rename the topic to "How do I get my actual BluRay backups to look just like the pirated ones I downloaded?"
    i was trying to be "nice", anytime i see someone ask how to "back up" a BD (or dvd for that matter) and it involves something other than burning an exact copy i automatically conclude that piracy rears it's head somewhere in the work flow pipeline.

    of course, considering my views on copyright laws and the fact that perhaps at certain times in my life i may have engaged in activities that in some countries may or may not be misconstrued as copyright violations, i am not so quick to denounce anyone else's activities, it just annoys me to no end when people seem to think they can take a commercially authored and pressed 35 mbps BD and re-encode it at the same resolution @ 4-5 mbps and make a near transparent copy of the original.
    You are misunderstanding my question. I have no problem backing up a BR to 4 or 5 GB. I was just asking if there has to be a standard or minimum bitrate in order to achieve HD quality. However, according to what I have read, bitrate doesnt matter as long as the resolution is 720 or above.
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  17. Member edDV's Avatar
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    VC-1 and h.264 have similar compression quality. Blu-Ray uses ~12-20 Mb/s. DVB HDTV does h.264 in the 8-12 Mb/s range. Those are your "typical" rates.

    If you compress below that, expect quality to drop fast. Many seem happy to downsize to 1280x720/24p at DVD rates to fit a movie to a single layer DVDR but that is way below Blu-Ray quality.

    Remember that an uncompressed 1920x1080/24p master will be in the 3000 Mb/s range so Blu-Ray is already over 100x compressed.
    Last edited by edDV; 16th Mar 2011 at 00:03.
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  18. Originally Posted by smackyourfupa View Post
    I was just asking if there has to be a standard or minimum bitrate in order to achieve HD quality. However, according to what I have read, bitrate doesnt matter as long as the resolution is 720 or above.
    Bitrate doesn't determine if the video is HD or not, that is only a matter of resolution. Bitrate certainly does matter as far as quality is concerned.
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    Originally Posted by smackyourfupa View Post
    Isnt h264 a higher quality encoding method than the method they use to encode blu-rays like vc-1 or mpeg 2? Wouldnt that explain how such a small h264 encoded file can come to in comparison to a 25-30gb blu ray?
    while mpeg-2, vc-1 and h264 may all be legal blu-ray codecs, almost all recent blu-rays i have seen are encoded using h264.

    in so far as being a "higher quality method", i would argue that vc-1 is just as good and just as advanced as h264.
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  20. Member edDV's Avatar
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    Originally Posted by deadrats View Post
    Originally Posted by smackyourfupa View Post
    Isnt h264 a higher quality encoding method than the method they use to encode blu-rays like vc-1 or mpeg 2? Wouldnt that explain how such a small h264 encoded file can come to in comparison to a 25-30gb blu ray?
    while mpeg-2, vc-1 and h264 may all be legal blu-ray codecs, almost all recent blu-rays i have seen are encoded using h264.

    in so far as being a "higher quality method", i would argue that vc-1 is just as good and just as advanced as h264.
    "higher quality" for one way compression ratio does not mean higher picture quality.

    Something being missed here and that is recode loss. The Blu-Ray makers encode from an uncompressed master. Decompression followed by recompression is lossy even if you recode to the same or higher bit rate. Recode to lower bit rate is very lossy because the surplus detail has already been removed.
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    [QUOTE=deadrats;2064655]
    Originally Posted by smackyourfupa View Post

    there seems to be this ridiculous notion that permeates the "back up" community that you can drop the bit rate to the absolute bare minimum and somehow retain almost all the original quality. this mind set has a second component in that the caveat is that the video codec used must be x264, somehow the imbeciles that create these back ups are convinced that a free open source h264 encoder is so vastly superior to the commercial 70 thousand dollar commercial grade h264 encoder that you can use 1/8 the bit rate and achieve the same results.
    I've never heard anyone try to argue that the open source h264 encoder is superior or that they are able to achieve the same quality at 1/8 the bitrate... but IMO it is VERY good.
    Would you say some encodes can be near bluray quality?
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    Originally Posted by jagabo View Post
    Originally Posted by smackyourfupa View Post
    I was just asking if there has to be a standard or minimum bitrate in order to achieve HD quality. However, according to what I have read, bitrate doesnt matter as long as the resolution is 720 or above.
    Bitrate doesn't determine if the video is HD or not, that is only a matter of resolution. Bitrate certainly does matter as far as quality is concerned.
    LOL yup, what I just said
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  23. Originally Posted by smackyourfupa View Post
    Originally Posted by jagabo View Post
    Originally Posted by smackyourfupa View Post
    I was just asking if there has to be a standard or minimum bitrate in order to achieve HD quality. However, according to what I have read, bitrate doesnt matter as long as the resolution is 720 or above.
    Bitrate doesn't determine if the video is HD or not, that is only a matter of resolution. Bitrate certainly does matter as far as quality is concerned.
    LOL yup, what I just said
    It's not the way I interpreted what you said because immediately before it you said "if there has to be a standard or minimum bitrate in order to achieve HD quality". To me that implied you were talking about the quality of the HD, not just the fact that it was HD.
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    Originally Posted by greymalkin View Post
    as has been said before, 720p and 1080p are simply resolutions (1280 x 720) or 1920 x 1080)
    No matter how low/high the bitrate, they can still be called "HD".

    The reason some "HD" looks good and some looks very soft/blocky/etc. depends on the bitrate chosen and whether it is appropriate for the source.

    A solid black background with someone talking is going to require less bitrate than a busy street scene because there is less movement from frame to frame in the first scenario. Digital video compression works by taking frames of video at set intervals and just tracking the differences from frame A to frame B. Lots of motions, lots of bitrate required..little motion..little bitrate required.

    So the bitrate requirements from one movie to the next (or even from one scene to the next in the same movie) could vary wildly.

    So..without a "standard"..what's a guy to do? I prefer using constant quality settings in my applications. It creates a variable bitrate file that gives it all it needs in the fast action and throttles it down in the slower/less complex scenes.
    I see what you mean. So far I've done 5 movies, all with constant quality of 18. The file sizes are varying from 1GB to almost 3GB. A 1 hr and 45 min movie ended up with a file size of 0.99 GB and another movie with the exact same running length had a size of 2.33 GB
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    Originally Posted by smackyourfupa View Post
    I've never heard anyone try to argue that the open source h264 encoder is superior or that they are able to achieve the same quality at 1/8 the bitrate... but IMO it is VERY good.
    Would you say some encodes can be near bluray quality?
    you're kidding right? check out the doom9 and doom10 forums, it's like a church of x264, any comparison where x264 is not found to be the clear and absolute winner is viewed at best with suspicion at worst with flat out derision about the testing methodology and insults about the intelligence of the tester.

    go look up posts by "lord mulder", he's a "software developer", where he claims that so long as you use x264 10 mb/s is more than enough for 1080p video or go read through "a diary of an x264 developer" where one of the two main x264 developers spends pages denouncing any test where his beloved software didn't win hands down and "explaining" why the tests were biased or flawed.

    hell, in this forum there a guy that goes by "poisondeathray", a good guy (<i think he's a guy), a helpful and knowledgeable chap but my God does he have the x264 blinders on super tight, ask him about the "virtues" of using x264 over any other h264 encoder, no matter what the cost.

    edit: as for whether or not i think some re-encodes can be near blu-ray quality i think that's a bit of a head fake; there are some blu-rays that are of such high quality to begin with that the drop in quality that invariably results from re-encoding at a much lower bit rate may not be immediately noticeable on an improperly calibrated smaller screen or tv, so in that sense yes, they can be near blu-ray quality but if you were to compare the original and the re-encode on a really good large hdtv i have no doubt in my mind that it would look like a pirated poor second or third generation dup.
    Last edited by deadrats; 19th Mar 2011 at 10:35.
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