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A program called Badaboom is in the works that uses a 8 or 9 series nvidia video card to convert a blu-ray disc to a x.264. I don't know any more than this article says but it sounds like exactly what we're waiting for. Unfortunately for me I just got rid of my 8800gt in favor of the 4850 (8800 has terrible drivers and crashes or causes regular errors for me).


Anyways, I think this is something to look forward to. Read the article http://anandtech.com/video/showdoc.aspx?i=3339
 

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Why would you want to decompress a compressed disc and then recompress it with a different codec? Why bother with HD if you are going to throw away the quality? Stick with DVD....


Vern
 

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because in theory you can get the same quality as the BD in a smaller filesize

my question is what about the audio? does it encode it in flac or something


I personally don't like re-encoding, but some people want to save a few GBs here and there
 

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Quote:
Originally Posted by tsb /forum/post/14169972


because in theory you can get the same quality as the BD in a smaller filesize

Yeah, it's called HD-DVD



Anyways, enough of the jokes... the audio is not encoded with this software, wasn't designed to do audio encoding.


You can do that yourself though.
 

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Quote:
Originally Posted by tsb /forum/post/14169972


because in theory you can get the same quality as the BD in a smaller filesize

my question is what about the audio? does it encode it in flac or something


I personally don't like re-encoding, but some people want to save a few GBs here and there

You can't get the same quality as the BD in a smaller filesize by re-encoding. Any re-encoding causes a loss in quality. If it's already encoded with H264 or VC1 at a high bit rate, that's as good as it's going to get, short of new codec and a re-encode using the master. Bear in mind any hardware based encode is always going to suffer in comparison to the job the studios do with their encodes, and the TLC (usually) that they put into it.


You could decrease the size by throwing away extra's and such, without re-encoding the video stream, or if you have a 720P TV it might be worth it to you to re-encode down to 720P.


I would guess that the big advantage of this hardware based re-encoding would be used on High Def OTA or QAM recording of TV shows, which are usually MPEG2, 60 fps. Re-encoding to AVC/VC1 and 24 fps or 30 fps will at least give some reasonable ratio of quality loss vs file size.
 

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Jeeze, why is it that anytime a discussion about compressing movies occurs there are always a bunch of wet blankets that have to constantly beat the drum about "loss of quality"?


Yeah, recompressing movies causes loss of quality. We all know that. That hasn't stoped it from being a huge activity, for many years, regardless of the format.


To all the purists out there that still haven't been able to grasp the benifits of recompression (even though it has been beaten to death) we'll go over it one more time.


Sometimes you don't need the full quality of the bluray disc and don't want the accosiated bloat. - Yup, that's it in a nutshell.


Now this can be broken down further and I'll use a little example.


1) No perceptable loss of quality - You buy a bluray and it will be used most of the time in your basement blasted out onto that 8 foot screen. You want the full quality and as such, that's why you bought the disc in the first place. You then realize that your wife is making you go along on the weekend trip to the inlaws and your laptop does not have a bluray drive. You now compress a few down to fit on the HDD and the picture still *looks* just as good because it is a 17" screen sitting on the table at the foot of the bed in the guest bedroom. Which is much better than sitting on the floor in the livingroom trying to watching some flavor of "Law & Order" (the only thing that tunes into their analog rabbit ears) each night while your wife and your mother in law sit there gossiping about the people from her high school that never left her home town in the first place...


2) Perceptable loss of quality that you are fine with - You're informed that the upcoming weekend at the inlaws has turned into a week long stay so that the grandkids can spend more time with grandma and grandpa and it is better to have a bunch of different movies at less than perfect quality than having to watch the same one or two over and over (which is still better than the fuzzy "Law & Order" with complimentary gabbing soundtrack overlaid.)


Not to mention the couple of backup copies that you leave on the Archos, because your laptop may just crap out and you don't want to be left there for a week with no redundant backup plan - your sanity is just not worth it.


-Suntan
 

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Quote:
Originally Posted by Suntan /forum/post/14171561


Jeeze, why is it that anytime a discussion about compressing movies occurs there are always a bunch of wet blankets that have to constantly beat the drum about "loss of quality"?


Yeah, recompressing movies causes loss of quality. We all know that. That hasn't stoped it from being a huge activity, for many years, regardless of the format.


To all the purists out there that still haven't been able to grasp the benifits of recompression (even though it has been beaten to death) we'll go over it one more time.


Sometimes you don't need the full quality of the bluray disc and don't want the accosiated bloat. - Yup, that's it in a nutshell.


Now this can be broken down further and I'll use a little example.


1) No perceptable loss of quality - You buy a bluray and it will be used most of the time in your basement blasted out onto that 8 foot screen. You want the full quality and as such, that's why you bought the disc in the first place. You then realize that your wife is making you go along on the weekend trip to the inlaws and your laptop does not have a bluray drive. You now compress a few down to fit on the HDD and the picture still *looks* just as good because it is a 17" screen sitting on the table at the foot of the bed in the guest bedroom. Which is much better than sitting on the floor in the livingroom trying to watching some flavor of "Law & Order" (the only thing that tunes into their analog rabbit ears) each night while your wife and your mother in law sit there gossiping about the people from her high school that never left her home town in the first place...


2) Perceptable loss of quality that you are fine with - You're informed that the upcoming weekend at the inlaws has turned into a week long stay so that the grandkids can spend more time with grandma and grandpa and it is better to have a bunch of different movies at less than perfect quality than having to watch the same one or two over and over (which is still better than the fuzzy "Law & Order" with complimentary gabbing soundtrack overlaid.)


Not to mention the couple of backup copies that you leave on the Archos, because your laptop may just crap out and you don't want to be left there for a week with no redundant backup plan - your sanity is just not worth it.


-Suntan

Sounds like my winter "vacation" in Wisconsin ha!


On another note, are some video formats not like flac in audio? As in it just COMPRESSES the video size but does not DEGRADE the quality?
 

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Quote:
On another note, are some video formats not like flac in audio? As in it just COMPRESSES the video size but does not DEGRADE the quality?

Yes .....but its more complicated than that. Most Blu ray films come in high bitrate AVC (h.264), VC-1(Microsoft) or good old MPEG-2. AVC has the highest compression ratio of the lot (followed very closely by VC-1) but MPEG-2 is way behind. So if we take a MPEG-2 movie at ~40 Mbps and compress this using AVC at ~20 Mbps we would end up with a file of approximatly half the size of the origional. Is their any loss in quality I here you ask? NO! Why you ask? Well the simple answer is that if care is taken to do the re-encode properly with decent settings then we get the benefit of the AVC codec being almost twice as efficient as the MPEG-2 codec.

However it doesn't stop their ....many Blu-ray films have very high bitrates and of course this suffers from the law of deminishing returns. The perceptable difference between the same video encoded at 5 Mbps and at 10 Mbps is quite large (assuming all other varriables are the same i.e. resolution, number of reference frames, no of B frames, quantisizer settings etc) ....noticable gain in quality. Now we do encodes at 15/20/25/30 Mbps and a last one at 35 Mbps. The noticable difference as we increase to each succesive bitrate reduces on a log scale meaning that by the time we get to the last one their is no PERCEPTABLE difference between this and the last. Of course their is a difference in turms of the data in the file but your eye can't tell what that is.

This is the reason that many people do re-encodes to save space, even using the same codecs.

We can then take this even further, what if we only have a 720p screen and we have 1080p material? We recompress to 720p and what do we get? Well you get loss in quality because now there is less than half the number of pixals and depending on the options and bitrate, possibly some of the colour depth. So the logical question is do we get any advantages? YES, many! We get of course reduced file sizes but in real terms if we do a good encode we can actually achieve better results than if we let a realtime scaler resize the video! Offline scaling will ALWAYS do a better job than a realtime one. In addition their are also other advantages to turning a Blu Ray into another file type, we do away with all that DRM, extra's (not everybody wants them), don't have to use commercial buggy players that charge a fortune only not to work as advertised, no HDCP issues, no requirement for specific hardware, monitors, no downres sound (using flac or the like) and the freedom to use any player we want to watch our movies on with an infinate amount of tweaks available unlike commercial players. Just my experiences and my 2c.

Cheers,

Jiff.
 

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I would imagine the quality would not be able to rival a good x264-AVIsynth encode ....these if done correctly look amazing!

Cheers,

Jiff.
 

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Some folks want to rip things so they can view them on their tiny portable device screens. Without some kind of hardware acceleration, the re-encode takes way too long for most folks to bother. With tech like this, it becomes more feasible.
 

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Quote:
Originally Posted by cavalierlwt /forum/post/14170148


You can't get the same quality as the BD in a smaller filesize by re-encoding. Any re-encoding causes a loss in quality. If it's already encoded with H264 or VC1 at a high bit rate, that's as good as it's going to get, short of new codec and a re-encode using the master. Bear in mind any hardware based encode is always going to suffer in comparison to the job the studios do with their encodes, and the TLC (usually) that they put into it.

But this isn't a hardware compression, not what's usually meant by "hardware compression". It's not a realtime hardware asic compressor, it's a software compression program that runs on special purpose/highly-parallel processors (GPUs).


As such it's not, or need not be incumbered by the limitations of "hardware compression", ie time, memory, etc.

Quote:
Originally Posted by Smitty2k1 /forum/post/14171588


On another note, are some video formats not like flac in audio? As in it just COMPRESSES the video size but does not DEGRADE the quality?

They exist, but they are not used to deliver video to consumers (heck, they're not even used that much in production). The reason is video is massive.


The most you can get our of lossless compression for HD video is about 60MB/sec (500Mbps) or about 10x the max bitrate of Blu-ray.
 

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Quote:
Originally Posted by rizorith /forum/post/14173181


That is very interesting. Do you have any more information on it? Might deserve a thread since so many of us are getting the 4800 series cards.

Nope. I haven't had a chance to play with it yet (will soon), but if you have a 4850, just download it and try it.
 

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Quote:
Originally Posted by Suntan /forum/post/14171561


Jeeze, why is it that anytime a discussion about compressing movies occurs there are always a bunch of wet blankets that have to constantly beat the drum about "loss of quality"?



-Suntan

Because someone always comes out and says that they can recompress a movie that's already compressed, and get the same quality. I fully agreed that for viewing on a different screens/situations, compression may be worth it. Yes, people do recognize the benefits in recompression, but I don't like to see people get misinformation.
 

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Quote:
Originally Posted by MikeSM /forum/post/14170189


Why wait for badaboom. if you have an ATI 4850, you apparently can do it now! Look here: http://downloads.guru3d.com/ATI-Aviv....html#download

Unfortunately the ATi Avivo XCoder utility is still CPU based. That's the same one which used to run on the X1k series. They've just modified the installer to install on the Radeon HD 4k series.
 
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