Harmony Central Forums
Announcement
Collapse
No announcement yet.

How much does a clip of digital audio "weigh" in filesize?

Collapse
X
  • Time
  • Show
Clear All
new posts

  • #16
    Originally posted by rasputin1963 View Post

    One loop I created was under 5Mb and thus was acceptable to upload; the B3 organ loop, also of four bars, 44.1/16 and same tempo... came to 5.66Mb.
    Hmmmm . . 0.66 MB represents about 6 seconds of mono or 3 seconds of stereo. 5 MB is a bit under a minute of mono, or 30 seconds of stereo. Isn't that kind of long for a loop? Still, at that length, a difference of a few seconds should be really easy to notice. Are you sure they're trimmed accurately, and to the same length?

    An easy test is to load each file into its own track in a multitrack DAW program (everbody has one these days). Line up the start of the files and see how much difference there is between the ends. Then figure out why.

    If you're into loops (and I'm not, myself) you know that the file needs to be edited very tightly at the beginning so the audio starts at the beginning of the file. The end can be tricky because you want some decay but you don't want it long enough to cause a noticeable drag in the time when looping the file around on itself. You have to cut off the tail at the point where the next beat would start.

    You probably know all that, but take a close look at what you've done and you should figure out why the files are of different sizes.
    --
    "Today's production equipment is IT-based and cannot be operated without a passing knowledge of computing, although it seems that it can be operated without a passing knowledge of audio." - John Watkinson, Resolution Magazine, October 2006
    Drop by http://mikeriversaudio.wordpress.com now and then

    Comment


    • #17
      Since he is uploading the files to some server the mystery may be there.

      Many streaming and storage sites use something called Wavpack. This is a Filer storage compression that saves space on servers except its non destructive and saves a waveform in a lossless compression schemes that can reduce a files storage size between 30%~70%.

      https://en.wikipedia.org/wiki/WavPack

      This is not the same compression used to chance sample sizes. Its more like a Win zip file (in fact win zip 11 incorporates this now) This storage compression provides full lossless restoration when you pull the file off the server for use. They also use this for storage on stand along and hand held recorders.

      The files actually stored on that server can thereby read very different sizes when you go on line and see what you have stored there. I suspect this is the issue. The OP is expecting his on line file sizes he saved to be a true representation of what he has there when in reality they been have been compressed. Once downloaded that should be the same size as when he uploaded them.

      This is why I asked he inspect the files with an audio editor and do some comparisons before uploading. He would know what he had based on length and content prior to uploading.

      Then if the two identical sized filed wind up being different sizes after they are uploaded it comes down to storage compression. One file may compress to a different size then another.
      Last edited by WRGKMC; 10-01-2015, 09:52 AM.

      Comment


      • #18
        Originally posted by WRGKMC View Post
        Since he is uploading the files to some server the mystery may be there.

        Many streaming and storage sites use something called Wavpack. This is a Filer storage compression that saves space on servers except its non destructive and saves a waveform in a lossless compression schemes that can reduce a files storage size between 30%~70%.
        But if it's supposed to save storage space, it isn't going to do that by making the file bigger. What Ras needs to do is look at the file size on his own computer before he uploads it. If it's under 5 MB there, it shouldn't be bigger than 5 MB when it gets to the loop host server. If some such data compression is going on, two WAV files of the same size might end up being different sizes after processing, but if both are 5 MB or smaller to start with, the processed versions should be smaller than 5 MB.

        Just to prove to myself that I wasn't making all this up, I made a file (about 30 seconds at 44.1 kHz 16-bit mono, which indeed came out to be about 2.5 MB) and duplicated it a few times. First I verified that all the copies were showed the same size in Windows. Then I normalized one, applied a goofy EQ curve to another, and compressed the third one to toothpaste, saved them all as 16-bit 44.1 kHz mono WAV files and they were still all the same size. Then I saved each one as an MP3 file and they were all different sizes.

        So, still, I maintain that the problem, if it's not something goofy going on with the host system, is that the files aren't really the same length.
        Last edited by MikeRivers; 10-01-2015, 02:31 PM.
        --
        "Today's production equipment is IT-based and cannot be operated without a passing knowledge of computing, although it seems that it can be operated without a passing knowledge of audio." - John Watkinson, Resolution Magazine, October 2006
        Drop by http://mikeriversaudio.wordpress.com now and then

        Comment


        • #19
          ^^ Agreed. I'd say since he based his file size on the tempo and measures being used. The organ clip must have sustained past the measures on either end and made the file longer or there's additional silence there that could be trimmed. From what it sounded to me he didn't know the file was longer then 5M until he tried to upload it. The server recognized it was too ling in size. I'm just not sure if the first file wasn't longer too and was compressible to 5M on the server.

          The simple solution would be to use a different free storage site. Drop box which doesn't have file size restrictions just total space. I have dozens of full length songs in wav format uploaded to that site. Its very reliable too.

          Comment

          Working...
          X