<?php
define('AUDIO', 0x08);
define('VIDEO', 0x09);
define('SCRIPT_DATA', 0x12);
define('FRAME_TYPE_INFO', 0x05);
define('CODEC_ID_AVC', 0x07);
define('CODEC_ID_AAC', 0x0A);
define('AVC_SEQUENCE_HEADER', 0x00);
define('AAC_SEQUENCE_HEADER', 0x00);
define('AVC_NALU', 0x01);
define('AVC_SEQUENCE_END', 0x02);
define('FRAMEFIX_STEP', 40);
define('INVALID_TIMESTAMP', -1);
class CLI
{
protected static $ACCEPTED = array();
var $params = array();
function __construct($options = false, $handleUnknown = false)
{
global $argc, $argv;
if ($options !== false)
self::$ACCEPTED = $options;
// Parse params
if ($argc > 1)
{
$paramSwitch = false;
for ($i = 1; $i < $argc; $i++)
{
$arg = $argv[$i];
$isSwitch = preg_match('/^-+/', $arg);
if ($isSwitch)
$arg = preg_replace('/^-+/', '', $arg);
if ($paramSwitch && $isSwitch)
$this->error("[param] expected after '$paramSwitch' switch (" . self::$ACCEPTED[1][$paramSwitch] . ')');
else if (!$paramSwitch && !$isSwitch)
{
if ($handleUnknown)
$this->params['unknown'][] = $arg;
else
$this->error("'$arg' is an invalid option, use --help to display valid switches.");
}
else if (!$paramSwitch && $isSwitch)
{
if (isset($this->params[$arg]))
$this->error("'$arg' switch can't occur more than once");
$this->params[$arg] = true;
if (isset(self::$ACCEPTED[1][$arg]))
$paramSwitch = $arg;
else if (!isset(self::$ACCEPTED[0][$arg]))
$this->error("there's no '$arg' switch, use --help to display all switches.");
}
else if ($paramSwitch && !$isSwitch)
{
$this->params[$paramSwitch] = $arg;
$paramSwitch = false;
}
}
}
// Final check
foreach ($this->params as $k => $v)
if (isset(self::$ACCEPTED[1][$k]) && $v === true)
$this->error("[param] expected after '$k' switch (" . self::$ACCEPTED[1][$k] . ')');
}
function displayHelp()
{
printf("%s:\n\n", "You can use script with following switches");
foreach (self::$ACCEPTED[0] as $key => $value)
printf(" --%-18s%s\n", $key, $value);
foreach (self::$ACCEPTED[1] as $key => $value)
printf(" --%-9s%-9s%s\n", $key, " [param]", $value);
}
function error($msg)
{
printf("%s\n", $msg);
exit(1);
}
function getParam($name)
{
if (isset($this->params[$name]))
return $this->params[$name];
else
return false;
}
}
function ReadByte($str, $pos)
{
$int = unpack('C', $str[$pos]);
return $int[1];
}
function ReadInt24($str, $pos)
{
$int32 = unpack('N', "\x00" . substr($str, $pos, 3));
return $int32[1];
}
function ReadInt32($str, $pos)
{
$int32 = unpack('N', substr($str, $pos, 4));
return $int32[1];
}
function WriteByte(&$str, $pos, $int)
{
$str[$pos] = pack('C', $int);
}
function WriteInt24(&$str, $pos, $int)
{
$str[$pos] = pack('C', ($int & 0xFF0000) >> 16);
$str[$pos + 1] = pack('C', ($int & 0xFF00) >> 8);
$str[$pos + 2] = pack('C', $int & 0xFF);
}
function WriteInt32(&$str, $pos, $int)
{
$str[$pos] = pack('C', ($int & 0xFF000000) >> 24);
$str[$pos + 1] = pack('C', ($int & 0xFF0000) >> 16);
$str[$pos + 2] = pack('C', ($int & 0xFF00) >> 8);
$str[$pos + 3] = pack('C', $int & 0xFF);
}
function WriteFlvTimestamp(&$flvTag, $tagPos, $packetTS)
{
WriteInt24($flvTag, $tagPos + 4, ($packetTS & 0x00FFFFFF));
WriteByte($flvTag, $tagPos + 7, ($packetTS & 0xFF000000) >> 24);
}
function LogDebug($msg)
{
global $debug;
if ($debug)
fwrite(STDERR, $msg . "\n");
}
function ShowHeader()
{
$header = "KSV FLV Fixer";
$len = strlen($header);
$width = floor((80 - $len) / 2) + $len;
$format = "\n%" . $width . "s\n\n";
printf($format, $header);
}
// Global code starts here
$flvHeader = pack("H*", "464c5601050000000900000000");
$flvHeaderLen = strlen($flvHeader);
$format = " %-8s%-16s%-16s%-8s";
$audio = false;
$debug = false;
$fixWindow = 1000;
$metadata = true;
$video = false;
$prevTagSize = 4;
$tagHeaderLen = 11;
$baseTS = INVALID_TIMESTAMP;
$negTS = INVALID_TIMESTAMP;
$prevAudioTS = INVALID_TIMESTAMP;
$prevVideoTS = INVALID_TIMESTAMP;
$pAudioTagLen = 0;
$pVideoTagLen = 0;
$pAudioTagPos = 0;
$pVideoTagPos = 0;
$prevAVC_Header = false;
$prevAAC_Header = false;
$AVC_HeaderWritten = false;
$AAC_HeaderWritten = false;
ShowHeader();
$options = array(
0 => array(
'help' => 'displays this help',
'debug' => 'show debug output',
'nometa' => 'do not save metadata in repaired file'
),
1 => array(
'fixwindow' => 'timestamp gap between frames to consider as timeshift',
'in' => 'input filename of flv file to be repaired',
'out' => 'output filename for repaired file'
)
);
$cli = new CLI($options);
if ($cli->getParam('help'))
{
$cli->displayHelp();
exit(0);
}
if ($cli->getParam('debug'))
$debug = true;
if ($cli->getParam('nometa'))
$metadata = false;
if ($cli->getParam('fixwindow'))
$fixWindow = $cli->getParam('fixwindow');
if ($cli->getParam('in'))
$in = $cli->getParam('in');
else
die("You must specify an input file\n");
if ($cli->getParam('out'))
$out = $cli->getParam('out');
else
die("You must specify an output file\n");
$timeStart = microtime(true);
if (file_exists($in))
{
$flvIn = fopen($in, "rb");
if (function_exists("stream_set_chunk_size"))
stream_set_chunk_size($flvIn, 8 * 1024 * 1024);
$flvTag = fread($flvIn, $flvHeaderLen);
if (strncmp($flvTag, "FLV", 3) != 0)
die("Input file is not a valid FLV file\n");
$fileLen = filesize($in);
$filePos = $flvHeaderLen;
$fileSize = $fileLen / (1024 * 1024);
$pFilePos = 0;
}
else
die("Input file doesn't exist\n");
$flvOut = fopen($out, "w+b");
if (!$flvOut)
die("Failed to create output file\n");
fwrite($flvOut, $flvHeader, $flvHeaderLen);
LogDebug(sprintf($format . "%-16s", "Type", "CurrentTS", "PreviousTS", "Size", "Position"));
while ($filePos < $fileLen)
{
$flvTag = fread($flvIn, $tagHeaderLen);
$tagPos = 0;
$packetType = ReadByte($flvTag, $tagPos);
$packetSize = ReadInt24($flvTag, $tagPos + 1);
$packetTS = ReadInt24($flvTag, $tagPos + 4);
$packetTS = $packetTS | (ReadByte($flvTag, $tagPos + 7) << 24);
// Try to fix the odd timestamps and make them zero based
$currentTS = $packetTS;
$lastTS = $prevVideoTS >= $prevAudioTS ? $prevVideoTS : $prevAudioTS;
$fixedTS = $lastTS + FRAMEFIX_STEP;
if (($baseTS == INVALID_TIMESTAMP) and (($packetType == AUDIO) or ($packetType == VIDEO)))
$baseTS = $packetTS;
if (($baseTS > 1000) and ($packetTS >= $baseTS))
$packetTS -= $baseTS;
if ($lastTS != INVALID_TIMESTAMP)
{
$timeShift = $packetTS - $lastTS;
if ($timeShift > $fixWindow)
{
LogDebug("Timestamp gap detected: PacketTS=" . $packetTS . " LastTS=" . $lastTS . " Timeshift=" . $timeShift);
if ($baseTS < $packetTS)
$baseTS += $timeShift - FRAMEFIX_STEP;
else
$baseTS = $timeShift - FRAMEFIX_STEP;
$packetTS = $fixedTS;
}
else
{
$lastTS = $packetType == VIDEO ? $prevVideoTS : $prevAudioTS;
if ($packetTS < ($lastTS - $fixWindow))
{
if (($negTS != INVALID_TIMESTAMP) and (($packetTS + $negTS) < ($lastTS - $fixWindow)))
$negTS = INVALID_TIMESTAMP;
if ($negTS == INVALID_TIMESTAMP)
{
$negTS = $fixedTS - $packetTS;
LogDebug("Negative timestamp detected: PacketTS=" . $packetTS . " LastTS=" . $lastTS . " NegativeTS=" . $negTS);
$packetTS = $fixedTS;
}
else
{
if (($packetTS + $negTS) <= ($lastTS + $fixWindow))
$packetTS += $negTS;
else
{
$negTS = $fixedTS - $packetTS;
LogDebug("Negative timestamp override: PacketTS=" . $packetTS . " LastTS=" . $lastTS . " NegativeTS=" . $negTS);
$packetTS = $fixedTS;
}
}
}
}
}
if ($packetTS != $currentTS)
WriteFlvTimestamp($flvTag, $tagPos, $packetTS);
$flvTag = $flvTag . fread($flvIn, $packetSize + $prevTagSize);
$totalTagLen = $tagHeaderLen + $packetSize + $prevTagSize;
if (strlen($flvTag) != $totalTagLen)
{
LogDebug("Broken FLV tag encountered! Aborting further processing.");
break;
}
switch ($packetType)
{
case AUDIO:
if ($packetTS > $prevAudioTS - $fixWindow)
{
$FrameInfo = ReadByte($flvTag, $tagPos + $tagHeaderLen);
$CodecID = ($FrameInfo & 0xF0) >> 4;
if ($CodecID == CODEC_ID_AAC)
{
$AAC_PacketType = ReadByte($flvTag, $tagPos + $tagHeaderLen + 1);
if ($AAC_PacketType == AAC_SEQUENCE_HEADER)
{
if ($AAC_HeaderWritten)
{
LogDebug(sprintf("%s\n" . $format, "Skipping AAC sequence header", "AUDIO", $packetTS, $prevAudioTS, $packetSize));
break;
}
else
{
LogDebug("Writing AAC sequence header");
$AAC_HeaderWritten = true;
}
}
else if (!$AAC_HeaderWritten)
{
LogDebug(sprintf("%s\n" . $format, "Discarding audio packet received before AAC sequence header", "AUDIO", $packetTS, $prevAudioTS, $packetSize));
break;
}
}
if ($packetSize > 0)
{
// Check for packets with non-monotonic audio timestamps and fix them
if (!(($CodecID == CODEC_ID_AAC) and (($AAC_PacketType == AAC_SEQUENCE_HEADER) or $prevAAC_Header)))
if (($prevAudioTS != INVALID_TIMESTAMP) and ($packetTS <= $prevAudioTS))
{
LogDebug(sprintf("%s\n" . $format, "Fixing audio timestamp", "AUDIO", $packetTS, $prevAudioTS, $packetSize));
$packetTS += (FRAMEFIX_STEP / 5) + ($prevAudioTS - $packetTS);
WriteFlvTimestamp($flvTag, $tagPos, $packetTS);
}
$pAudioTagPos = ftell($flvOut);
fwrite($flvOut, $flvTag, $totalTagLen);
if ($debug)
LogDebug(sprintf($format . "%-16s", "AUDIO", $packetTS, $prevAudioTS, $packetSize, $pAudioTagPos));
if (($CodecID == CODEC_ID_AAC) and ($AAC_PacketType == AAC_SEQUENCE_HEADER))
$prevAAC_Header = true;
else
$prevAAC_Header = false;
$prevAudioTS = $packetTS;
$pAudioTagLen = $totalTagLen;
}
else
LogDebug(sprintf("%s\n" . $format, "Skipping small sized audio packet", "AUDIO", $packetTS, $prevAudioTS, $packetSize));
}
else
LogDebug(sprintf("%s\n" . $format, "Skipping audio packet", "AUDIO", $packetTS, $prevAudioTS, $packetSize));
if (!$audio)
$audio = true;
break;
case VIDEO:
if ($packetTS > $prevVideoTS - $fixWindow)
{
$FrameInfo = ReadByte($flvTag, $tagPos + $tagHeaderLen);
$FrameType = ($FrameInfo & 0xF0) >> 4;
$CodecID = $FrameInfo & 0x0F;
if ($FrameType == FRAME_TYPE_INFO)
{
LogDebug(sprintf("%s\n" . $format, "Skipping video info frame", "VIDEO", $packetTS, $prevVideoTS, $packetSize));
break;
}
if ($CodecID == CODEC_ID_AVC)
{
$AVC_PacketType = ReadByte($flvTag, $tagPos + $tagHeaderLen + 1);
if ($AVC_PacketType == AVC_SEQUENCE_HEADER)
{
if ($AVC_HeaderWritten)
{
LogDebug(sprintf("%s\n" . $format, "Skipping AVC sequence header", "VIDEO", $packetTS, $prevVideoTS, $packetSize));
break;
}
else
{
LogDebug("Writing AVC sequence header");
$AVC_HeaderWritten = true;
}
}
else if (!$AVC_HeaderWritten)
{
LogDebug(sprintf("%s\n" . $format, "Discarding video packet received before AVC sequence header", "VIDEO", $packetTS, $prevVideoTS, $packetSize));
break;
}
}
if ($packetSize > 0)
{
$pts = $packetTS;
if (($CodecID == CODEC_ID_AVC) and ($AVC_PacketType == AVC_NALU))
{
$cts = ReadInt24($flvTag, $tagPos + $tagHeaderLen + 2);
$cts = ($cts + 0xff800000) ^ 0xff800000;
$pts = $packetTS + $cts;
if ($cts != 0)
LogDebug("DTS: $packetTS CTS: $cts PTS: $pts");
}
// Check for packets with non-monotonic video timestamps and fix them
if (!(($CodecID == CODEC_ID_AVC) and (($AVC_PacketType == AVC_SEQUENCE_HEADER) or ($AVC_PacketType == AVC_SEQUENCE_END) or $prevAVC_Header)))
if (($prevVideoTS != INVALID_TIMESTAMP) and ($packetTS <= $prevVideoTS))
{
LogDebug(sprintf("%s\n" . $format, "Fixing video timestamp", "VIDEO", $packetTS, $prevVideoTS, $packetSize));
$packetTS += (FRAMEFIX_STEP / 5) + ($prevVideoTS - $packetTS);
WriteFlvTimestamp($flvTag, $tagPos, $packetTS);
}
$pVideoTagPos = ftell($flvOut);
fwrite($flvOut, $flvTag, $totalTagLen);
if ($debug)
LogDebug(sprintf($format . "%-16s", "VIDEO", $packetTS, $prevVideoTS, $packetSize, $pVideoTagPos));
if (($CodecID == CODEC_ID_AVC) and ($AVC_PacketType == AVC_SEQUENCE_HEADER))
$prevAVC_Header = true;
else
$prevAVC_Header = false;
$prevVideoTS = $packetTS;
$pVideoTagLen = $totalTagLen;
}
else
LogDebug(sprintf("%s\n" . $format, "Skipping small sized video packet", "VIDEO", $packetTS, $prevVideoTS, $packetSize));
}
else
LogDebug(sprintf("%s\n" . $format, "Skipping video packet", "VIDEO", $packetTS, $prevVideoTS, $packetSize));
if (!$video)
$video = true;
break;
case SCRIPT_DATA:
if ($metadata)
{
$pMetaTagPos = ftell($flvOut);
fwrite($flvOut, $flvTag, $totalTagLen);
LogDebug(sprintf($format . "%-16s", "META", $packetTS, 0, $packetSize, $pMetaTagPos));
}
break;
}
$filePos += $totalTagLen;
$cFilePos = floor($filePos / (1024 * 1024));
if ($cFilePos > $pFilePos)
{
printf("Processed %d/%.2f MB\r", $cFilePos, $fileSize);
$pFilePos = $cFilePos;
}
}
// Set proper Audio/Video marker
WriteByte($flvHeader, 4, $audio << 2 | $video);
fseek($flvOut, 0);
fwrite($flvOut, $flvHeader, $flvHeaderLen);
fclose($flvIn);
fclose($flvOut);
$timeEnd = microtime(true);
$timeTaken = sprintf("%.2f", $timeEnd - $timeStart);
printf("Processed input file in %s seconds\n", $timeTaken);
printf("Finished\n");
?>