hls-test/extract-playlist.php
2023-03-02 14:23:42 -08:00

466 lines
No EOL
14 KiB
PHP

<?php
define( 'MOV_TFHD_BASE_DATA_OFFSET', 0x01 );
define( 'MOV_TFHD_STSD_ID', 0x02 );
define( 'MOV_TFHD_DEFAULT_DURATION', 0x08 );
define( 'MOV_TFHD_DEFAULT_SIZE', 0x10 );
define( 'MOV_TFHD_DEFAULT_FLAGS', 0x20 );
define( 'MOV_TFHD_DURATION_IS_EMPTY', 0x010000 );
define( 'MOV_TFHD_DEFAULT_BASE_IS_MOOF', 0x020000 );
define( 'MOV_TRUN_DATA_OFFSET', 0x01 );
define( 'MOV_TRUN_FIRST_SAMPLE_FLAGS', 0x04 );
define( 'MOV_TRUN_SAMPLE_DURATION', 0x100 );
define( 'MOV_TRUN_SAMPLE_SIZE', 0x200 );
define( 'MOV_TRUN_SAMPLE_FLAGS', 0x400 );
define( 'MOV_TRUN_SAMPLE_CTS', 0x800 );
class MP4Reader {
/**
* @var resource $file
*/
protected $file;
public function __construct( $file ) {
$this->file = $file;
}
/**
* @return int
*/
public function pos() {
$pos = ftell( $this->file );
if ( $pos === false ) {
throw new Exception( 'Failed to read position in MP4 file' );
}
return $pos;
}
/**
* @param int $length number of bytes to read
* @return string|false raw bytes or false on eof
*/
public function readBytes( $length ) {
$bytes = fread( $this->file, $length );
if ( feof( $this->file ) ) {
return false;
}
if ( $bytes === false || strlen( $bytes ) < $length ) {
throw new Exception( "Failed to read $length bytes from MP4 file" );
}
return $bytes;
}
/**
* @param int $length number of bytes to skip over
*/
private function skipBytes( $length ) {
$retval = fseek( $this->file, $length, SEEK_CUR );
if ( $retval < 0 ) {
throw new Exception( "Failed to skip ahead $length bytes in MP4 file" );
}
}
/**
* @return int|false 64-bit integer value or false on eof
*/
public function read64() {
$bytes = $this->readBytes( 8 );
if ( $bytes === false ) {
return false;
}
$data = unpack( 'Jval', $bytes );
return $data['val'];
}
/**
* @return int|false 32-bit integer value or false on eof
*/
public function read32() {
$bytes = $this->readBytes( 4 );
if ( $bytes === false ) {
return false;
}
$data = unpack( 'Nval', $bytes );
return $data['val'];
}
/**
* @return int|false 24-bit integer value or false on eof
*/
public function read24() {
$bytes = $this->readBytes( 3 );
if ( $bytes === false ) {
return false;
}
$data = unpack( 'Nval', "\x00$bytes" );
return $data['val'];
}
/**
* @return int|false 16-bit integer value or false on eof
*/
public function read16() {
$bytes = $this->readBytes( 2 );
if ( $bytes === false ) {
return false;
}
$data = unpack( 'nval', $bytes );
return $data['val'];
}
/**
* @return int|false 8-bit integer value or false on eof
*/
public function read8() {
$bytes = $this->readBytes( 1 );
if ( $bytes === false ) {
return false;
}
return ord( $bytes );
}
/**
* @return string|false 4-byte type code or false on eof
*/
public function readType() {
return $this->readBytes( 4 );
}
/**
* @param callable $callback in the form function(MP4Box)
* @return bool true on success, or false on eof
*/
public function readBox( $callback ) {
$start = $this->pos();
$size = $this->read32();
if ( $size === false ) {
return false;
}
$end = $start + $size;
$type = $this->readType();
if ( $type === false ) {
return false;
}
$box = new MP4Box( $this->file, $start, $size, $type );
$retval = call_user_func( $callback, $box );
$remaining = $end - $this->pos();
if ( $remaining > 0 ) {
$this->skipBytes( $remaining );
}
return true;
}
/**
* Scan a series of boxes and pass control based on type.
* Unrecognized boxes will be skipped over.
* @param callable[] $map array of callables keyed by fourCC type code
*/
public function boxes( $map ) {
$ok = true;
while ( $ok ) {
$ok = $this->readBox( function ( $box ) use ( $map ) {
$handler = $map[$box->type] ?? false;
if ( is_callable( $handler ) ) {
call_user_func( $handler, $box );
} else if ( is_array( $handler ) ) {
$box->boxes( $handler );
} else if ( $handler === false ) {
// no-op
} else {
throw new Exception( "Unexpected callback or map type for type $box->type" );
}
} );
}
}
}
class MP4FileReader extends MP4Reader {
/**
* @param string $filename
*/
public function __construct( $filename ) {
$file = fopen( $filename, 'rb' );
if ( !$file ) {
throw new Exception( 'Failed to open MP4 input file' );
}
parent::__construct( $file );
}
function __destruct() {
if ( $this->file ) {
fclose( $this->file );
$this->file = null;
}
}
}
class MP4Box extends MP4Reader {
public $start;
public $size;
public $type;
public function __construct( $file, $start, $size, $type ) {
parent::__construct( $file );
$this->start = $start;
$this->size = $size;
$this->type = $type;
}
public function end() {
return $this->start + $this->size;
}
public function remaining() {
return $this->end() - $this->pos();
}
public function readBytes( $length ) {
if ( $length > $this->remaining() ) {
return false;
}
return parent::readBytes( $length );
}
}
function hexdump( $str ) {
$out = '';
$len = strlen( $str );
for ( $i = 0; $i < $len; $i++ ) {
$char = $str[$i];
$byte = ord( $char );
// really?
$digits = str_pad( dechex( $byte ), 2, '0', STR_PAD_LEFT );
$out .= $digits;
}
return $out;
}
function safestr( $str ) {
$out = '';
$len = strlen( $str );
for ( $i = 0; $i < $len; $i++ ) {
$char = $str[$i];
$byte = ord( $char );
if ( $byte >= 32 && $byte <= 126 ) {
$out .= $char;
} else {
$out .= '.';
}
}
return $out;
}
/**
* @param string $filename - input MP4 file to read
* @return array[] - list of segment info
*/
function extractFragmentedMP4( $filename ) {
$segments = [];
$mp4 = new MP4FileReader( $filename );
$eof = false;
$moof = false;
$timestamp = 0.0;
$duration = 0.0;
$timescale = 0;
$dts = 0;
$first_pts = 0;
$max_pts = 0;
$init = false;
/*
Need to:
- find the end of the moov; everything up to that is the initialization segment
- https://www.w3.org/TR/mse-byte-stream-format-isobmff/#iso-init-segments
- find the start of each styp+moof fragment
- https://www.w3.org/TR/mse-byte-stream-format-isobmff/#iso-media-segments
- find the start timestamp of each moof fragment
- find the duration of each moof fragment
moov.trak.mdia.mdhd.timescale - looks useful 12288 for 24fps?
moov.trak.mdia.mdhd.duration - 0 on the moov
moov.mvex.trex.default_sample_duration - 0 on the moov
moof.traf.tfhd.default_sample_duration is 512 on these
moof.traf.tfdt.baseMediaDecodeTime is 0 on the first, 122880 on the second frag (10 seconds in?)
moof.mdat.sample_duration is empty here (uses default I guess?)
moof.mdat.sample_composition_time_offset also empty
opus has timescale 48000 in moov.trak.mdia.mdhd
*/
$mp4->boxes( [
'moov' => [
'trak' => [
'mdia' => [
'mdhd' => function ( $box ) use ( &$timescale ) {
$version = $box->read8();
$flags = $box->read24();
if ( $version == 1 ) {
$box->read64();
$box->read64();
} else {
$box->read32();
$box->read32();
}
$timescale = $box->read32();
}
],
],
],
'moof' => function ( $box ) use ( &$segments, &$moof, &$init, &$timestamp, &$duration, &$dts, &$first_pts, &$max_pts, &$timescale ) {
if ( !$init ) {
$init = [
'start' => 0,
'size' => $box->start,
'timestamp' => 0.0,
'duration' => 0.0,
];
$segments['init'] = $init;
}
$moof = $box->start;
$default_sample_duration = 0;
$first_pts = 0;
$max_pts = 0;
$box->boxes( [
'traf' => [
'tfhd' => function( $box ) use ( &$default_sample_duration ) {
$version = $box->read8();
$flags = $box->read24();
$track_id = $box->read32();
if ( $flags & MOV_TFHD_BASE_DATA_OFFSET ) {
$box->read64();
}
if ( $flags & MOV_TFHD_STSD_ID ) {
$box->read32();
}
if ( $flags & MOV_TFHD_DEFAULT_DURATION ) {
$default_sample_duration = $box->read32();
}
},
'trun' => function( $box ) use ( &$default_sample_duration, &$dts, &$first_pts, &$max_pts ) {
$version = $box->read8();
$flags = $box->read24();
$entries = $box->read32();
if ( $flags & MOV_TRUN_DATA_OFFSET ) {
$box->read32();
}
if ( $flags & MOV_TRUN_FIRST_SAMPLE_FLAGS ) {
$box->read32();
}
for ( $i = 0; $i < $entries; $i++ ) {
$pts = $dts;
$sample_duration = $default_sample_duration;
if ( $flags & MOV_TRUN_SAMPLE_DURATION ) {
$sample_duration = $box->read32();
}
if ( $flags & MOV_TRUN_SAMPLE_SIZE ) {
$box->read32();
}
if ( $flags & MOV_TRUN_SAMPLE_FLAGS ) {
$box->read32();
}
if ( $flags & MOV_TRUN_SAMPLE_CTS ) {
$pts += $box->read32();
}
if ( $i == 0 ) {
$first_pts = $pts;
}
$max_pts = max( $max_pts, $pts + $sample_duration );
$dts += $sample_duration;
}
echo "$first_pts - $max_pts\n";
}
],
] );
},
'mdat' => function ( $box ) use ( &$segments, &$moof, &$first_pts, &$max_pts, &$timescale ) {
var_dump( $first_pts );
var_dump( $max_pts );
var_dump( $timescale );
array_push( $segments, [
'start' => $moof,
'size' => $box->end() - $moof,
'timestamp' => $first_pts / $timescale,
'duration' => ( $max_pts - $first_pts ) / $timescale,
] );
}
] );
return $segments;
}
function playlist( $filename, $segments ) {
/*
#EXTM3U
#EXT-X-VERSION:7
#EXT-X-TARGETDURATION:10
#EXT-X-MEDIA-SEQUENCE:0
#EXT-X-PLAYLIST-TYPE:VOD
#EXT-X-MAP:URI="new-vp9.mp4",BYTERANGE="811@0"
#EXTINF:10.000000,
#EXT-X-BYTERANGE:1058384@811
new-vp9.mp4
#EXTINF:10.000000,
#EXT-X-BYTERANGE:1085979@1059195
new-vp9.mp4
#EXTINF:10.000000,
#EXT-X-BYTERANGE:1268619@2145174
new-vp9.mp4
#EXTINF:10.000000,
#EXT-X-BYTERANGE:1418664@3413793
new-vp9.mp4
#EXTINF:10.000000,
#EXT-X-BYTERANGE:1129265@4832457
new-vp9.mp4
...
#EXT-X-ENDLIST
*/
$lines = [];
$lines[] = "#EXTM3U";
$lines[] = "#EXT-X-TARGETDURATION:10";
$lines[] = "#EXT-MEDIA-SEQUENCE:0";
$lines[] = "#EXT-PLAYLIST-TYPE:VOD";
$init = $segments['init'] ?? false;
if ( $init ) {
$lines[] = "#EXT-X-MAP:URI=\"$filename\",BYTERANGE=\"{$init['size']}@{$init['start']}\"";
$lines[] = $filename;
}
$n = count( $segments ) - 1;
for ( $i = 0; $i < $n; $i++ ) {
$segment = $segments[$i];
$lines[] = "#EXTINF:{$segment['duration']}";
$lines[] = "#EXT-X-BYTERANGE:{$segment['size']}@{$segment['start']}";
$lines[] = $filename;
}
return implode( "\n", $lines );
}
$argv = $_SERVER['argv'];
$self = array_shift( $argv );
$filename = array_shift( $argv );
$segments = extractFragmentedMP4( $filename );
//var_dump( $segments );
/*
foreach ( $segments as $key => $segment ) {
if ( $key === 'init' ) {
print "$key {$segment['start']},{$segment['size']}\n";
} else {
print "$key {$segment['timestamp']},{$segment['duration']} @ {$segment['start']},{$segment['size']}\n";
}
}
*/
$m3u8 = playlist( urlencode( $filename ), $segments );
print $m3u8 . "\n";