Does anybody know why Dolby TrueHD and DTS-HD MA compressions can achieve bitrates of 18Mbps and 24Mbps respectively when LPCM uncompressed only achieves 6.9Mbps at 5.1 (24bit/48khz)? What other possible information are their to encode to have these lossless formats go up that high?
Lossless vs. Uncompressed audio
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Well, all three formats support a sampling rate of up to 96kHz (I'm not sure if any support higher sampling rates than that on HD DVD or BD) for one, and while lossless compression results in a lower overall bitrate and file size, it actually on occasion requires more bandwidth than uncompressed audio for certain parts. Though generally it's by an incredibly small amount, apparently.
I don't quite understand that last part myself, so here's where I found it: http://en.wikipedia.org/wiki/Lossles...e_files_longer
Other than that, I don't know.
I don't quite understand that last part myself, so here's where I found it: http://en.wikipedia.org/wiki/Lossles...e_files_longer
Other than that, I don't know.
Those top figures quoted by Dolby and DTS refer to peak bit rates for losslessly packed 24/192 LPCM, ex. 5.1 24/192 LPCM = 27.6 Mbps.
I don't know about other codecs, but lossless TrueHD and DTS-HD MA audio never requires more bandwidth than uncompressed. For example, 24/48 TrueHD peak bitrates are just slightly higher than the standard bitrate for 16/48 LPCM.
Those top figures quoted by Dolby and DTS refer to peak bit rates for losslessly packed 24/192 LPCM, ex. 5.1 24/192 LPCM = 27.6 Mbps.
I don't know about other codecs, but lossless TrueHD and DTS-HD MA audio never requires more bandwidth than uncompressed. For example, 24/48 TrueHD peak bitrates are just slightly higher than the standard bitrate for 16/48 LPCM.
I am not willing to criticize Fox for this...why?
Because, at least, there is a lossless track on Fox BDs that have been released so far(as opposed to some studios...cough, Warner, cough...that give us lossy DD
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IIRC, DTS was late in getting the spec to the Hardware People.
Next gen players should have the decoding ability...I hope.
Quote:
Originally Posted by bferr1 /forum/post/0
What irks me is that full DTS-HD MA decoding will only be accomplished after another round of expensive player/receiver replacements, just so we can get the equivalent of the uncompressed PCM that we're already getting.
Thanks a lot, Fox.![]()
I am not willing to criticize Fox for this...why?
Because, at least, there is a lossless track on Fox BDs that have been released so far(as opposed to some studios...cough, Warner, cough...that give us lossy DD
IIRC, DTS was late in getting the spec to the Hardware People.
Next gen players should have the decoding ability...I hope.
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I am very willing to criticize Fox for their decision to use DTS-MA. They could just have easily used TrueHD. That codec provides the same quality as DTS-MA at the same or lower bitrates AND it is currently supported in the only BD player that counts to them, the PS3. With the latest firmware updates, and Pioneer and Samsung's most recent players, TrueHD will also be supported in many standalone (BD) players as well.
BTW, Warner has used TrueHD lossless more than any other studio, so your little snide remark is just that.
I am very willing to criticize Fox for their decision to use DTS-MA. They could just have easily used TrueHD. That codec provides the same quality as DTS-MA at the same or lower bitrates AND it is currently supported in the only BD player that counts to them, the PS3. With the latest firmware updates, and Pioneer and Samsung's most recent players, TrueHD will also be supported in many standalone (BD) players as well.
BTW, Warner has used TrueHD lossless more than any other studio, so your little snide remark is just that.
I think I'm with you on this one, Robert, although I do not wish to derail this thread further, so I'll keep it brief. I can see where oink is coming from vis-a-vis Warner, but what good is offering a lossless codec that no one can use unless they invest in yet another round of expensive equipment upgrades? To me, that's as consumer-unfriendly as their high prices, scant special features and ever-changing release schedule.
And since Fox is the only studio widely using the DTS-HD MA codec, who else is there to criticize? If they only used Dolby TrueHD, as Robert suggests, then we likely wouldn't be clamoring for DTS-HD MA decoding. The HD DVD people sure don't seem to be.
I think I'm with you on this one, Robert, although I do not wish to derail this thread further, so I'll keep it brief. I can see where oink is coming from vis-a-vis Warner, but what good is offering a lossless codec that no one can use unless they invest in yet another round of expensive equipment upgrades? To me, that's as consumer-unfriendly as their high prices, scant special features and ever-changing release schedule.
And since Fox is the only studio widely using the DTS-HD MA codec, who else is there to criticize? If they only used Dolby TrueHD, as Robert suggests, then we likely wouldn't be clamoring for DTS-HD MA decoding. The HD DVD people sure don't seem to be.
but the question was
the answer is that the higher limit is not for 5.1 24/48 but because there could be more channels and higher sampeling frequency.
I think only Chronos has better then 48 and I think there are ahandful of titles with more then 5.1
but we have also not seen any title anywhere near 18mbps either
but the question was
the answer is that the higher limit is not for 5.1 24/48 but because there could be more channels and higher sampeling frequency.
I think only Chronos has better then 48 and I think there are ahandful of titles with more then 5.1
but we have also not seen any title anywhere near 18mbps either
but DTHD also requires DD, while DTS MA does not.
they also released more without lossless. Most of us just want to have lossless sound and we don't care if it is PCM or DTHD (or even DTS MA for that matter).
The issue with Warner is that they purposefully gimped some titles with lossy on the BD side (even though lossless did exist and would fit) in order to try and get dual owners to buy the HD DVD and artificially raise HD DVD sales. In the process screwing anyone that decided not to waist their money on a useless format and not to help this dumb war to continue until it kills both.
but DTHD also requires DD, while DTS MA does not.
they also released more without lossless. Most of us just want to have lossless sound and we don't care if it is PCM or DTHD (or even DTS MA for that matter).
The issue with Warner is that they purposefully gimped some titles with lossy on the BD side (even though lossless did exist and would fit) in order to try and get dual owners to buy the HD DVD and artificially raise HD DVD sales. In the process screwing anyone that decided not to waist their money on a useless format and not to help this dumb war to continue until it kills both.
most of us are reasonable enough to know that this won't be our last player. I bet most people that fear upgrades are not out there buying HD players right now
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LG has used it as well. Also SC on the HD DVD side
well if you read several threads you will see that it is most likely not because they don't need it but it looks like they have a phobia about lossless
most of us are reasonable enough to know that this won't be our last player. I bet most people that fear upgrades are not out there buying HD players right now
LG has used it as well. Also SC on the HD DVD side
well if you read several threads you will see that it is most likely not because they don't need it but it looks like they have a phobia about lossless
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One question. When watching a Dolby True HD or DTS HD MA movie etc. You set the Player (PS3) on PCM not Bitstream.. I'm useing a Panny XR57 w/HDMI
btw
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btw
Blu-Ray will never decode the new Dolby True-HD and DTS-HDMA in the players (except PS-3 with Dolby True-HD). They will simple convert the signal to PCM or send it as is over HDMI-1.3 to be decoded by the recievor. We can keep waiting until the stars align, but it ain't going to happen.
That is one of the flaws of the Blu-Ray specification.
That is one of the flaws of the Blu-Ray specification.
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Although HD DVD and Blu-Ray don't support 14 discrete sound channels, Dolby TrueHD is capable of carrying 14 discrete sound channel 24/192. I think that is where the maximum bitrate of 18 mbps is used. But I could be wrong I'm just speculating since 5.1 24/48 has an average bitrate of 3.4 mbps.
Although HD DVD and Blu-Ray don't support 14 discrete sound channels, Dolby TrueHD is capable of carrying 14 discrete sound channel 24/192. I think that is where the maximum bitrate of 18 mbps is used. But I could be wrong I'm just speculating since 5.1 24/48 has an average bitrate of 3.4 mbps.
I will have to check. I think there is one or two but don't remember by heart
I guess you have not been to the high def area in a long time. The problem with most HD DVDers is that they are not here to learn anything, nor here to ask for what they want but here just to BS and prop up HD DVD, that is why for them HF having DTHD over the BD version is extremely important and means the world but then when you point out that lossless is not used as much on HD DVD, they say it is not important because you can't hear the difference. Or they make up a new stupid rule like "Warner has more DTHD titles" eliminate studios that use PCM and DTS MA that all do the same job just to make a stupid point.
PS going back to your original point.
the problem is that the last sentence does not support the first. Like I pointed out (and you agreed) studios on both side use DTS MA and no player on either side can support it. That there are people on the BD side asking for it and not on the HD DVD side (like you pointed out) is not because of a format differential but because of character of the people.
I will have to check. I think there is one or two but don't remember by heart
I guess you have not been to the high def area in a long time. The problem with most HD DVDers is that they are not here to learn anything, nor here to ask for what they want but here just to BS and prop up HD DVD, that is why for them HF having DTHD over the BD version is extremely important and means the world but then when you point out that lossless is not used as much on HD DVD, they say it is not important because you can't hear the difference. Or they make up a new stupid rule like "Warner has more DTHD titles" eliminate studios that use PCM and DTS MA that all do the same job just to make a stupid point.
PS going back to your original point.
the problem is that the last sentence does not support the first. Like I pointed out (and you agreed) studios on both side use DTS MA and no player on either side can support it. That there are people on the BD side asking for it and not on the HD DVD side (like you pointed out) is not because of a format differential but because of character of the people.
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