IPB

Welcome Guest ( Log In | Register )

 
Reply to this topicStart new topic
Does Flac Files Have Joint Stereo vs. Normal Stereo like mp3?
poetryrocksalot
post Aug 10 2008, 01:10
Post #1





Group: Members
Posts: 14
Joined: 13-July 08
Member No.: 55754



I converted a flac album into mp3 and my option was to keep the original stereo settings from the source file. When I checked the album, all songs were is MS Joint Stereo. I thought flac files only used stereo format.So does flac files also used MS Joint Stereo, or is my program reading it wrong?

Also, if I convert a flac file that is in joint stereo format into a stereo only mp3, will I have loss in quality (for changing stereo format)?
Go to the top of the page
+Quote Post
pdq
post Aug 10 2008, 01:18
Post #2





Group: Members
Posts: 3412
Joined: 1-September 05
From: SE Pennsylvania
Member No.: 24233



Lossless formats can take advantage of the similarity between left and right channels as well, but because they are lossless it makes no difference when they are decoded. The decoded file is identical to the original regardless. When reencoding to mp3 or other lossy format, the data goes through an intermediate PCM format that is strictly L/R, so the encoding of the lossless file can't possibly influence the encoding of the lossy file.

Besides, you are aware that joint stereo encoding is superior to forced stereo encoding?
Go to the top of the page
+Quote Post
uart
post Aug 10 2008, 15:29
Post #3





Group: Members
Posts: 810
Joined: 23-November 04
Member No.: 18295



I wonder if the general ingnorance surrounding joint stereo will ever end?
Go to the top of the page
+Quote Post
XI8 1337
post Aug 10 2008, 15:44
Post #4





Group: Members
Posts: 69
Joined: 10-October 07
From: Sydney
Member No.: 47723



@poetryrocksalot:Please, read this.
QUOTE
"Don't confuse Joint Stereo (Stereo mode 1) with the Joint Stereo coding used for MPEG layer 2 encoding - it is not the same. Joint Stereo (Stereo mode 1) encoding for MPEG layer3 allows the XingMP3 Encoder to use additional methods of encoding, specifically - MS Stereo (Middle/Side Stereo), and for lower bitrates only, Intensity Stereo, in addition to the Independent Channel coding used for Stereo mode 0. MS Stereo uses one channel to encode information that is identical on the left and right channels and the other channel to encode the differences between the two channels. Intensity Stereo encodes only bits that are perceived to be important to the stereophonic image. The XingMP3 Encoder uses Intensity Stereo only in low bitrate files, (96kbps or less) where file size is critical to the user. In Joint Stereo (Stereo mode 1), the encoder dynamically (frame by frame) chooses the method of encoding that produces the best quality for each individual frame. Dynamic encoding improves compression efficiency which results in a higher quality file using less bits. Stereo mode 0 encodes the left and right channels independently. The total bitrate remains constant, but the split between the channels can vary. The XingMP3 Encoder uses this flexibility to improve quality by allocating more bits to the channel with the more dynamic signal. For MPEG layer 3 encoding, Stereo mode 0 limits the encoder to only one method of encoding - Independent Channels. Because Stereo mode 0 is limited to one method of encoding, Joint Stereo (Stereo mode 1) in most cases produces higher quality. In the exceptions, the Stereo mode 0 quality will be essentially equivalent to Joint Stereo (Stereo mode 1)."


QUOTE
The technique of manipulating stereo audio signals in Mid/Side format was devised solely for the purpose of enhancing audio compression. As far as uncompressed audio is concerned, it offers no benefits whatsoever. On the other hand, neither does it have any drawbacks - other than the fact that it is slightly more complex to handle than simple stereo.


[Source]

Joint stereo is not as bad as you think.

EDIT: Added the second, shorter quote.

This post has been edited by XI8 1337: Aug 10 2008, 15:46


--------------------
http://www.last.fm/user/Red_Crayon
Go to the top of the page
+Quote Post

Reply to this topicStart new topic
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:

 



RSS Lo-Fi Version Time is now: 30th September 2014 - 15:55