Posted by J. Clarke on 03/26/07 13:45

aniramca@yahoo.com wrote:
> On Mar 26, 1:47 am, "Barry Graham" <btgra...@tpg.com.au> wrote:
>> <anira...@yahoo.com> wrote in message
>>
>> news:1174881757.404156.165890@l77g2000hsb.googlegroups.com...
>>
>>> On Mar 25, 10:19 pm, Laurence Payne
>>> <lpayne1NOSPAM@dslDOTpipexDOTcom> wrote:
>>> I still wonder, despite
>>> of the 30 years or more of the midi invention, that they managed to
>>> package the sound of an instrument (such as piano or other
>>> instruments) into those tiny storage file.
>>
>> You're still missing the point.
>> There are NO SOUNDS in a MIDI file.
>> It just contains instructions that are sent to a sound device that
>> simulates the instrument sounds.
>>
>> -------------------------------------
>> Barry Graham
>> Melbourne, Australia
>
> Thanks. I now understand that midi appears to be just a "box of
> instruction" , and there is no sound in it. Is this then similar to
> vidoe avi file (MPEG4)? Somebody also indicated in another newsgroup
> that avi file is just a container with instruction on how to put
> together the sound portion and the video portion.
> However, how come does the instruction in an avi file end up being so
> large... example a 5 minutes video ends up to about 60 MB file? One
> can always argue that the instruction in avi is much more complex than
> midi, therefore larger file. Why is there so much larger file?
> Basically going back to midi... if midi can created a 15 min
> instruction to piano music in 70 kB, why "instruction" of avi files
> almost 1000 times more? Just curious

I think you have a serious misconception about MIDI. MIDI was intended
to control _physical_ instruments--sound boards used to and sometimes
still do come with MIDI connectors to which musical instruments can be
connected.

The MIDI instructions are more or less "press this key this far this
fast this hard hold this long" and the like, with the intent being that
some mechanical device on the instrument will actually move to make the
sound.

Since that time, programs have been written that contain simulations of
musical instruments that can accept MIDI instructions and play them
entirely on the computer. The results can vary widely for different
simulations and for different settings on the simulations.

In a sense MIDI is analogous to the old paper-roll "player pianos" but
much more sophisticated.

AVI files and the like are in no wise similar to MIDI except to the
extent that they are files stored on a computer. They contain the full
content, not instructions to an instrument.

Something in the video realm that would be more analogous to MIDI would
be a set of instructions to an animation program that caused animated
characters to go through a series of motions--that could be quite
compact but the results would not be the same, or necessarily much like
the same, on all players.

I think you're confusing the nature of AVI as a "container format" with
MIDI as a set of instructions.

--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

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