Re: Problem inserting tempo event (for a simple php script)

"Alex" <[email protected]> writes:

> Hi. I am trying to create MIDI using PHP.
                                       ^^^
!

> The problem I have is, how do I add a TEMPO event to this MIDI?
> Tempo structure:
> FF 51 03 tt tt tt
> where tttttt = New tempo, in us/quarter-note, in 24-bit binary
>
> Let's say I want to add a tempo of 500000 to the beginning of the track,
> what should I do?

$tempo = 500000;
$byte_0 = $tempo / 0x10000;
$tempo = $tempo % 0x10000;
$byte_1 = $tempo / 0x100;
$byte_2 = $tempo % 0x100;

Then add the bytes in order: $byte_0 $byte_1 $byte_2

in Perl: $file .= pack "CCC", $byte_0, $byte_1, $byte_2;

-- 
David Riley 		[email protected]