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[rhom]

the bit rate column in mc works fine for constant bitrates but if you use variable it's pretty much pointless as it just shows the first chunks (or an average?) bitrate.

is there any way that the actual cbr value that was used to encode the file can be displayed?  is that value actually stored in the headers somewhere or is only each chunks individual bitrate stored?

[Mr ChriZ]

I'm confused by your question..

I don't know what you refer to as a chunk? 
I believe Bitrate is done on a file by file (usually but not always meaning track by track) basis.
And as far as I know this is what the bitrate column shows:

If the files were ripped using a constant bit rate (cbr) then the column shows the constant
bit rate. (The file has an exact number of bits per second)

If the files were ripped using a variable bit rate(vbr), then the column shows the average bit rate over the entire
file.  The number of bits per second goes up and down each second depending on how much it was possible to compress them using the algorithm that was used to rip the file from the audio source.

Of course MC can display both vbr and cbr compressed files at the same time, so the only thing that I can see that
MC could show is whether the file is vbr or cbr, although really I can't think of a reason why you'd need to see this? (I'm not sure whether MC can or not)

I don't think theres any more information that can be shown?

[Alex B]

Also, it depends on the file format and the used encoder. Some file formats have the average bitrate information available, some not.

For example, VBR MP3 files encoded with LAME show accurate bitrates, but some VBR files encoded with other encoders don't provide that information. Then MC reads a short passage in the beginning of the file and estimates the bitrate.

WMA VBR files show something like "the needed bandwidth". The displayed value is not exactly the maximum peak bitrate, but usually more than overall average bitrate.

With VBR files the bitrate value is less tied to the actual file quality than with CBR files. More important is the quality level used when the file was encoded. The resulting average bitrate varies greatly according to the complexity of the source material.

[rhom]

what i mean is that if i encode (when ripping to mp3 via MC) and have it set to variable i want to know what the max bitrate was that i used was once  the file is in MC.

eg1, rip at 128vbr and then rip again at 320vbr - in MC which file was done with which?  how can i display the original rate of 128 or 320 in MC?

i started out relatively low (128vbr) and now have more disk space to go higher (not lossless though) and i've been re-ripping my music but now i can't really tell which tracks were ripped with the lower bitrate because i can't see what the actual vbr rate was, it only shows (as you say) the average.



btw. the "chunks" i was referring to are the discrecrete lengths of digital audio at individual variable bitrates, presumably as the file is encoded it is broken down into "chunks" and the best bitrate is used for each "chunk", thus variable.  i wasn't sure if the bitrate displayed in MC for vbr files was the first "chunk's" rate or an average.

ps. please don't bring up lossless is better, i know that.  i'd do it if i could but i don't have the money to spend on hdd's for the amount of music i have - "cheap" (in relation to hdd's) is relative depending upon income so we're not going there in this thread ok.

[Alex B]

what i mean is that if i encode (when ripping to mp3 via MC) and have it set to variable i want to know what the max bitrate was that i used was once  the file is in MC.

eg1, rip at 128vbr and then rip again at 320vbr - in MC which file was done with which?  how can i display the original rate of 128 or 320 in MC?

i started out relatively low (128vbr) and now have more disk space to go higher (not lossless though) and i've been re-ripping my music but now i can't really tell which tracks were ripped with the lower bitrate because i can't see what the actual vbr rate was, it only shows (as you say) the average. ...

MC does not have 128VBR or 320VBR options. What exact settings did you use? I might be able to instruct how to discriminate the files with a third party tool.

[rhom]

i really don't remember, the rates i mentioned were for illustrative purposes, most of them were done with MC9/10 a year to two years ago and i have no idea what they are anymore, thus my problem.

i'm currently re-ripping and encoding with preset fast extreme, so it would be nice if i could even just tell these new ones apart from the older variable bitrates but it doesn't seem possible.

how does anyone actually compare vbr files if you can't tell what 'max' bitrate was that they were originally encoded at?  it seems a rather obvious thing to store in the file instead of an 'average', which as far as i can see would be pointless on vbr files.

[Mr ChriZ]

i really don't remember, the rates i mentioned were for illustrative purposes, most of them were done with MC9/10 a year to two years ago and i have no idea what they are anymore, thus my problem.

i'm currently re-ripping and encoding with preset fast extreme, so it would be nice if i could even just tell these new ones apart from the older variable bitrates but it doesn't seem possible.

how does anyone actually compare vbr files if you can't tell what 'max' bitrate was that they were originally encoded at?  it seems a rather obvious thing to store in the file instead of an 'average', which as far as i can see would be pointless on vbr files.

Because the Max value wouldn't tell you any more than the average does.   If a really simple piece of music
were to be compressed even with a high quality VBR setting, the max number of bits per second could end
up really low because the bit patterns could be compressed so easily.

On the other hand a really complex piece of music could end with a fairly high Max Bit rate even tho using
a low quality setting, simply because that much information would be needed to represent the complex changing patterns.

All that could be added to the current information is the actual settings used with the encoder, which
would require extra tag info...

You could put your new files in a seperate place on your drive....
or use a slightly different naming technique...
Not Ideal admitidly...

[Alex B]

In other words, even a lower quality setting VBR file that averages at 128 kbps can have some peaks that reach 320 kbps. You cannot determine the used settings from the maximum bitrate.

The LAME header may contain information about the used settings. You could try these tools for finding the differences: http://www.guerillasoft.co.uk/encspot/, http://www.burrrn.net/?page_id=5 and http://fileforum.betanews.com/detail/Audio_Identifier/1115667842/1.

Actually, you should trust your ears in the first hand. If the files don't sound bad why rerip them? Some music genres don't need high VBR bitrates to sound fine. If you are unsure about the quality then go ahead.

[rhom]

sorry, by 'max' i meant -

preset fast extreme is currently encoded at bitrates between 220 and 260* so the 'max' bitrate would be 260, each level has it's own 'max' so it wouldn't appear to be too difficult to use this value as the bitrate.

i had previously assumed that vbr encoded files went from 0 to whatever value you entered, ie encode using any bitrate up to my 'max' to get as much data in as possible (sort of like each chunk has it's own bitrate but it can't go higher than my max value), i didn't realise that it was a smaller range (i'm sure MC used to do it the first way, maybe older versions of MC/lame allowed this?)

either way it should't really matter, whatever the maximum bitrate the file was encoded at should be in the bitrate field for vbr files to make any comparision useful.


perhaps my thinking is flawed about how vbr actually works?



*according to the hydrogen audio web page of lame settings (if i'm reading it correctly)

[GHammer]

Personally I would not want a fixed value displayed.
I understand VBR and I like the ~ display of the average.

I think you are trying to mix ABR and VBR here.

Compress a few times from the command line with LAME and watch what goes on 'under the hood' of MC.

That'll give you a better understanding of how VBR works.

[hit_ny]

eg1, rip at 128vbr and then rip again at 320vbr - in MC which file was done with which?  how can i display the original rate of 128 or 320 in MC?

You cant get this and for this reason i created a custom field called Encoder.

I use mp3s exclusively so in this field i enter in the encoder detected by encspot or lame header info, to get that i use lametag. I set it up as an extern al prog in MC, so right click->Send To->Send To(external)->LameTag gives me a console window with the header info. If its not lame encoded then i use encspot.

i typically enter encoder name + quality settings eg. Lame 3.90 (Q.I=78, APE -b192)

[Alex B]

sorry, by 'max' i meant -

preset fast extreme is currently encoded at bitrates between 220 and 260* so the 'max' bitrate would be 260, each level has it's own 'max' so it wouldn't appear to be too difficult to use this value as the bitrate.

... *according to the hydrogen audio web page of lame settings (if i'm reading it correctly)

The bitrates at HA are average bitrates. The maximum bitrate for --preset fast extreme (= -V0 --vbr-new) is 320 kbps. The maximum bitrate for the other -V values is also 320 kbps, except perhaps at the lowest quality settings (-V 6-9). The minimum bitrate for all LAME 3.97 --vbr-new settings is 32 kbps.

I have tested the v. 3.97 average bitrate behavior at all V settings and published my findings here: http://www.hydrogenaudio.org/forums/index.php?showtopic=37011&view=findpost&p=328558

[Mr ChriZ]

I have tested the v. 3.97 average bitrate behavior at all V settings and published my findings here: http://www.hydrogenaudio.org/forums/index.php?showtopic=37011&view=findpost&p=328558

Very pretty