PHP + Code Igniter Timecode Calculation Logic Error
- by Tim
Hello everyone, I have what I suspect to be a logic problem with an algorithm I am using to work with Video timecode in PHP. All help is appreciated.
The Objective
Well basically I want to work with timecode and perform calculations
For those not familiar with timecode it looks like this
01:10:58:12 or HH:MM:SS:FF 'AKA' HOURS:MINUTES:SECONDS:FRAMES
I have used the script from HERE to help me with working with this format.
The Problem
Now can i just say that this script works!!! Timecode calculations (in this case additions) are being performed correctly. However this script continually throws the following errors, yet still produces the correct output when I try and do the following calculation
00:01:26:00 + 00:02:00:12
The errors from this calculation are shown below
A PHP Error was encountered
Severity: Notice
Message: Undefined index: key
Filename: staff/tools.php
Line Number: 169
A PHP Error was
encountered
Severity: Notice
Message: Undefined index: key
Filename: staff/tools.php
Line Number: 169
Line Number 169 is in the parseInput() function
// feed it into the tc array
$i=0;
foreach ($tc AS $key=>$value) {
if ( is_numeric($array["$i"]) ) {
$tc["$key"]= $array["$i"];
if ($tc["$key"] < 10 && $tc["$key"] > 0 && strlen($tc['key'])==1 ) $tc["$key"]= "0".$tc["$key"];
}
$i++;
}
return $tc;
Now I should also mention that the number of times the above error is thrown depends on what I am calculating
00:00:00:00 + 00:00:00:00
returns no errors.
01:01:01:01 + 02:02:02:02
produces 8 of the above errors.
For your reference, here is the code in it's entirety
function add_cue_sheet_clips_process()
{
$sheetID = $_POST['sheet_id'];
$clipName = $_POST['clip_name'];
$tcIn = $_POST['tc_in'];
$tcOut = $_POST['tc_out'];
// string $input
// returns an associative array of hours, minutes, seconds, and frames
//
function parseInput ($input) {
// timecode should look something like hh:mm:ss;ff
// allowed separators are : ; . ,
// values may be single or double digits
// hours are least-significant -- 5.4 == 00:00:05;04
$tc= array("frames"=>"00", "seconds"=>"00", "minutes"=>"00", "hours"=>"00");
$punct= array(":", ";", ".", ",");
// too big? too small?
$input= trim($input);
if (strlen($input)>11 || $input=="") {
// invalid input, too long -- bzzt
return $tc;
}
// normalize punctuation
$input= str_replace( $punct, ":", $input);
// blow it up and reverse it so frames come first
$array= explode(":", $input);
$array= array_reverse($array);
// feed it into the tc array
$i=0;
foreach ($tc AS $key=>$value) {
if ( is_numeric($array["$i"]) ) {
$tc["$key"]= $array["$i"];
if ($tc["$key"] < 10 && $tc["$key"] > 0 && strlen($tc['key'])==1 ) $tc["$key"]= "0".$tc["$key"];
}
$i++;
}
return $tc;
}
// array $tc
// returns a float number of seconds
//
function tcToSec($tc) {
$wholeseconds= ($tc['hours']*3600) + ($tc['minutes'] * 60) + ($tc['seconds']);
$partseconds= ( $tc['frames'] / 25 );
$seconds= $wholeseconds + $partseconds;
return $seconds;
}
// float $seconds
// bool $subtract
// returns a timecode array
//
function secToTc ($seconds=0, $subtract=0) {
$tc= array("frames"=>"00", "seconds"=>"00", "minutes"=>"00", "hours"=>"00");
$partseconds= fmod($seconds, 1);
$wholeseconds= $seconds - $partseconds;
// frames
if ($subtract==1) $tc['frames']= floor( $partseconds * 25 );
else $tc['frames']= floor( $partseconds * 25 );
// hours
$tc['hours']= floor( $wholeseconds / 3600 );
$minsec= ($wholeseconds - ($tc['hours'] * 3600));
// minutes
$tc['minutes']= floor( $minsec / 60 );
// seconds
$tc['seconds']= ( $minsec - ($tc['minutes'] * 60) );
// padding
foreach ( $tc AS $key=>$value ) {
if ($value > 0 && $value < 10) $tc["$key"]= "0".$value;
if ($value=="0") $tc["$key"]= "00";
}
return $tc;
}
// array $tc
// returns string of well-formed timecode
//
function tcToString (&$tc) {
return $tc['hours'].":".$tc['minutes'].":".$tc['seconds'].";".$tc['frames'];
}
$timecodeIN = parseInput($tcIn);
$timecodeOUT = parseInput($tcOut);
// normalized inputs...
$tc1 = tcToString($timecodeIN);
$tc2 = tcToString($timecodeOUT);
// get seconds
$seconds1 = tcToSec($timecodeIN);
$seconds2 = tcToSec($timecodeOUT);
$result = $seconds1 + $seconds2;
$timecode3 = secToTc($result, 0);
$timecodeDUR = tcToString($timecode3);
$clipArray = array('clip_name' => $clipName, 'tc_in' => $tcIn, 'tc_out' => $tcOut, 'tc_duration' => $timecodeDUR);
$this->db->insert('tools_cue_sheets_clips', $clipArray);
redirect('staff/tools/add_cue_sheet_clips/'.$sheetID);
}
I hope this is enough information for someone to help me get on top of this, I would be extremely greatful.
Thanks,
Tim
