diff options
Diffstat (limited to 'containerchan/videodata.php')
| -rw-r--r-- | containerchan/videodata.php | 173 |
1 files changed, 0 insertions, 173 deletions
diff --git a/containerchan/videodata.php b/containerchan/videodata.php deleted file mode 100644 index d54d484b..00000000 --- a/containerchan/videodata.php +++ /dev/null @@ -1,173 +0,0 @@ -<?php -/* This file is dedicated to the public domain; you may do as you wish with it. */ -require dirname(__FILE__) . '/matroska.php'; - -function matroskaSeekElement($name, $pos) { - return ebmlEncodeElement('Seek', - ebmlEncodeElement('SeekID', ebmlEncodeElementName($name)) - . ebmlEncodeElement('SeekPosition', pack('N', $pos)) - ); -} - -// Make video from single WebM keyframe -function muxWebMFrame($videoTrack, $frame) { - $lenSeekHead = 73; - $lenCues = 24; - - // Determine version for EBML header - $version = 2; - $videoAttr = $videoTrack->get('Video'); - if (isset($videoAttr)) { - if ($videoAttr->get('StereoMode') !== NULL) $version = 3; - if ($videoAttr->get('AlphaMode') !== NULL) $version = 3; - } - if ($videoTrack->get('CodecDelay') !== NULL) $version = 4; - if ($videoTrack->get('SeekPreRoll') !== NULL) $version = 4; - if ($frame->name() == 'BlockGroup' && $frame->get('DiscardPadding') !== NULL) $version = 4; - - // EBML header - $ebml = ebmlEncodeElement('EBML', - ebmlEncodeElement('DocType', "webm") - . ebmlEncodeElement('DocTypeVersion', chr($version)) - . ebmlEncodeElement('DocTypeReadVersion', "\x02") - ); - - // Segment - $info = ebmlEncodeElement('Info', - ebmlEncodeElement('Duration', "\x41\x20\x00\x00") - . ebmlEncodeElement('MuxingApp', 'ccframe') - . ebmlEncodeElement('WritingApp', 'ccframe') - ); - $tracks = ebmlEncodeElement('Tracks', - ebmlEncodeElement('TrackEntry', $videoTrack->content()->readAll()) - ); - $cues = ebmlEncodeElement('Cues', - ebmlEncodeElement('CuePoint', - ebmlEncodeElement('CueTime', "\x00") - . ebmlEncodeElement('CueTrackPositions', - ebmlEncodeElement('CueTrack', pack('N', $videoTrack->get('TrackNumber'))) - . ebmlEncodeElement('CueClusterPosition', pack('N', $lenSeekHead + strlen($info) + strlen($tracks) + $lenCues)) - ) - ) - ); - if (strlen($cues) != $lenCues) throw new Exception('length of Cues element wrong'); - $cluster = ebmlEncodeElement('Cluster', - ebmlEncodeElement('Timecode', "\x00") - . ebmlEncodeElement($frame->name(), $frame->content()->readAll()) - . ebmlEncodeElement('Void', '') - ); - $seekHead = ebmlEncodeElement('SeekHead', - matroskaSeekElement('Info', $lenSeekHead) - . matroskaSeekElement('Tracks', $lenSeekHead + strlen($info)) - . matroskaSeekElement('Cues', $lenSeekHead + strlen($info) + strlen($tracks)) - . matroskaSeekElement('Cluster', $lenSeekHead + strlen($info) + strlen($tracks) + $lenCues) - ); - if (strlen($seekHead) != $lenSeekHead) throw new Exception('length of SeekHead element wrong'); - $segment = ebmlEncodeElement('Segment', $seekHead . $info . $tracks . $cues . $cluster); - - return $ebml . $segment; -} - -// Locate first WebM keyframe of track $trackNumber after timecode $skip -function firstWebMFrame($segment, $trackNumber, $skip=0) { - foreach($segment as $x1) { - if ($x1->name() == 'Cluster') { - $cluserTimecode = $x1->Get('Timecode'); - foreach($x1 as $blockGroup) { - $blockRaw = NULL; - if ($blockGroup->name() == 'SimpleBlock') { - $blockRaw = $blockGroup->value(); - } elseif ($blockGroup->name() == 'BlockGroup') { - $blockRaw = $blockGroup->get('Block'); - } - if (isset($blockRaw)) { - $block = new MatroskaBlock($blockRaw); - if ($block->trackNumber == $trackNumber && $block->keyframe) { - if (!isset($cluserTimecode) || $cluserTimecode + $block->timecode >= $skip) { - return $blockGroup; - } elseif (!isset($frame1)) { - $frame1 = $blockGroup; - } - } - } - } - } - } - return isset($frame1) ? $frame1 : NULL; -} - -function videoData($filename) { - $data = array(); - - // Open file - $fileHandle = fopen($filename, 'rb'); - if (!$fileHandle) { - error_log('could not open file'); - return $data; - } - - try { - $root = readMatroska($fileHandle); - $data['container'] = $root->get('EBML')->get('DocType'); - - // Locate segment information and tracks - $segment = $root->get('Segment'); - if (!isset($segment)) throw new Exception('missing Segment element'); - - // Get segment information - $info = $segment->get('Info'); - if (isset($info)) { - $timecodeScale = $info->get('TimecodeScale'); - $duration = $info->get('Duration'); - if (isset($timecodeScale) && isset($duration)) { - $data['duration'] = 1e-9 * $timecodeScale * $duration; - } - } - - // Locate video track - $tracks = $segment->get('Tracks'); - if (!isset($tracks)) throw new Exception('missing Tracks element'); - foreach($tracks as $trackEntry) { - if ($trackEntry->name() == 'TrackEntry' && $trackEntry->get('TrackType') == 1) { - $videoTrack = $trackEntry; - break; - } - } - if (!isset($videoTrack)) throw new Exception('no video track'); - - // Get track information - $videoAttr = $videoTrack->get('Video'); - if (!isset($videoAttr)) throw new Exception('missing video parameters'); - $pixelWidth = $videoAttr->get('PixelWidth'); - $pixelHeight = $videoAttr->get('PixelHeight'); - if (!isset($pixelWidth) || !isset($pixelHeight)) throw new Exception('no width or height'); - if ($pixelWidth == 0 || $pixelHeight == 0) throw new Exception('bad PixelWidth/PixelHeight'); - $displayWidth = $videoAttr->get('DisplayWidth', $pixelWidth); - $displayHeight = $videoAttr->get('DisplayHeight', $pixelHeight); - if ($displayWidth == 0 || $displayHeight == 0) throw new Exception('bad DisplayWidth/DisplayHeight'); - $data['width'] = $displayWidth; - $data['height'] = $displayHeight; - - // Extract frame to use as thumbnail - if ($videoAttr->get('AlphaMode') != NULL) { - if (!($pixelWidth % 2 == 0 && $pixelHeight % 2 == 0 && $displayWidth % 2 == 0 && $displayHeight % 2 == 0)) { - throw new Exception('preview frame blocked due to Chromium bug'); - } - } - $trackNumber = $videoTrack->get('TrackNumber'); - if (!isset($trackNumber)) throw new Exception('missing track number'); - if (isset($data['duration']) && $data['duration'] >= 5) { - $skip = 1e9 / $timecodeScale; - } else { - $skip = 0; - } - $frame = firstWebMFrame($segment, $trackNumber, $skip); - if (!isset($frame)) throw new Exception('no keyframes'); - $data['frame'] = muxWebMFrame($videoTrack, $frame); - } catch (Exception $e) { - error_log($e->getMessage()); - } - - fclose($fileHandle); - return $data; -} |