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MikaelSmoot
Nov 27, 2009, 12:25 PM
is it at all possible to rip and encode a dvd lossless like a cd for plaback in itunes, iphone, and appletv



J the Ninja
Nov 27, 2009, 12:44 PM
You will get A. HUGE. FILE.


Technically, I think you can do it with Handbrake by shoving the quality slider all the way to right. Unlike a CD though, a DVD is stored on the disc in a lossy format. It's not that big of a deal to transcode it.

ReggaeFire
Nov 28, 2009, 07:30 AM
Unlike a CD though, a DVD is stored on the disc in a lossy format.

Actually CDs are also a "lossy" format, it just depends on where you draw the line. The level of compression on CDs was determined by a fairly arbitrary way (the story being they needed to compress the music enough to fit a certain 72 minute symphony on one disc). That's why there are higher quality alternatives like DVD-A and SACD.


Anyway, in regards to the question, yes it's possible, but not as easy to do as converting it to a high quality file. Depending on how you rip the DVD (if you leave the whole disc intact, vs. removing unwanted languages and special features) you will have a file that is (again, depending on the length of the film) typically between 2.5 and 6 gigs, with the average being roughly a bit over 4 gigs. Handbrake doesn't have an option for a "lossless" conversion, but the highest settings will result in a very high quality rip.

Teej guy
Nov 28, 2009, 08:17 AM
Actually CDs are also a "lossy" format, it just depends on where you draw the line. The level of compression on CDs was determined by a fairly arbitrary way (the story being they needed to compress the music enough to fit a certain 72 minute symphony on one disc). That's why there are higher quality alternatives like DVD-A and SACD.

No, CDs are not a "lossy" format. They're not compressing the music to fit on the disc. It's PCM data. By that logic, DVD-A (PCM) and SACD (DSD) are both lossy as well. There is a loss when you digitise data, in the same way that there's a loss when you record to tape. How much of a loss depends on your A/D converters. However, there's no psychoacoustic codec deciding what data to throw away and what data to keep (which is how MP3/AAC/WMA/etc work) so it's considered lossless within the confines of whatever samplerate/bitdepth has been selected. CD is 16-bit/44.1kHz. The audio is sampled 44100 times a second and has 65536 possible levels to be recorded at. 24-bit/96kHz on the other hand is sampled 96000 a second but has a staggering 16777216 possible levels to be recorded at.

DVDs are lossy (...most of the time). Whereas CDs give you an exact representation of the 44.1/16-bit data generated for them (as long as they're not scratched/error correction is working/etc), the video and audio on DVDs is compressed using lossy codecs. Dolby and DTS are codecs (just like MP3 etc) and attempt to be transparent to the source (but are often not, the former more than the latter, it also depends on the bitrate.) Sometimes you see a PCM soundtrack on DVDs as well, and that will be a perfect representation of the data as digitised at whatever sampling rate and bit-depth has been selected. The lossy video compression uses a "combination of spatial image compression and temporal motion compensation." (thanks Wiki, I'm an audio guy, not a video guy.) Again, this attempts to be transparent to the source, but is often not.

GermanSuplex
Nov 29, 2009, 03:04 AM
To me, the h.264 videos with Handbrake are darn-near transparent at 720x480 and are half the size (or less) then the file on the DVD, and in some cases I can reach transparency at 640x480, especially for action-less movies.

If you are going to transcode at an overkill constant quality rate, you may as well just rip the disc to the PC since the file size will be similar and, in some cases, the transcoded file may be bigger than the original.

DoFoT9
Nov 29, 2009, 03:17 AM
MacThe Ripper anybody?