HLSProcessing.php

<?php
/* This program is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

function processHLS(){
    global $session_dir, $mpd_url, $mpd_features,                                   // Client block input
            $current_period, $current_adaptation_set, $current_representation,      // HLS process data
            $progress_xml, $progress_report, $reprsentation_error_log_template,     // Reporting
            $hls_manifest_type,                                                     // HLS data
            $cmaf_conformance, $cmaf_function_name, $cmaf_when_to_call,             // CMAF data
            $ctawave_conformance, $ctawave_function_name, $ctawave_when_to_call;    // CTA WAVE data
    
    $StreamInfURLArray = array();
    $IframeURLArray = array();
    $XMediaURLArray = array();
    $CodecArray = array();
    
    ## Open related files
    $progress_xml = simplexml_load_string('<root><Progress><percent>0</percent><dataProcessed>0</dataProcessed><dataDownloaded>0</dataDownloaded><CurrentAdapt>1</CurrentAdapt><CurrentRep>1</CurrentRep></Progress><completed>false</completed><allDownloadComplete>false</allDownloadComplete></root>');
    $progress_xml->asXml($session_dir . '/' . $progress_report);
    
    ## Read each line of manifest file into an array
    $m3u8 = playlistToArray($mpd_url);
    
    if($m3u8){
        ## If the manifest is a master playlist
        ## extract the urls to stream_inf, iframe and x_media playlists from master playlist and save them in separate arrays
        ## If the manifest is a media playlist
        ## extract the urls to either stream_inf or iframe and save it into arrays
        if($hls_manifest_type=="MasterPlaylist"){
            list($StreamInfURLArray, $IframeURLArray,$XMediaURLArray, $CodecArray) = playlistURLs($m3u8);
        }
        else{
            if(strpos(file_get_contents($mpd_url),"#EXT-X-I-FRAMES-ONLY")) 
                $IframeURLArray[0] =$mpd_url;
            else
                $StreamInfURLArray[0]=$mpd_url;
        }
        
        ## Download segments from stream_inf playlists, x_media playlists, and Iframe playlists
        if($cmaf_conformance)
            $return_arr = $cmaf_function_name($cmaf_when_to_call[0]);
        if($ctawave_conformance)
            $return_arr = $ctawave_function_name($ctawave_when_to_call[0]);
        $file_location = validate_segment_hls(array($StreamInfURLArray, $IframeURLArray,$XMediaURLArray), $CodecArray);
        
        ## Group the playlists together
        groupPlaylists($file_location);
        
        ## Crete $mpd_features structure since it is used in conformance server checks
        formMpdFeatures();
        
        ## Perform enforced profile segment validation
        $current_period = 0;
        $current_adaptation_set = 0;
        $current_representation = 0;
        $adapts = $mpd_features['Period'][$current_period]['AdaptationSet'];
        while($current_adaptation_set < sizeof($adapts)){
            $reps = $adapts[$current_adaptation_set]['Representation'];
            
            while($current_representation < sizeof($reps)){
                $error_log = str_replace(array('$AS$', '$R$'), array($current_adaptation_set, $current_representation), $reprsentation_error_log_template);
                
                if($cmaf_conformance)
                    $return_seg_val[] = $cmaf_function_name($cmaf_when_to_call[1]);
                
                err_file_op(1);
                print_console($session_dir . '/Period0/' . $error_log . '.txt', "Period 1 AdaptationSet " . ($current_adaptation_set+1) . " Representation " . ($current_representation+1) . " Results");
                $current_representation++;
            }
            
            if($cmaf_conformance)
                $return_arr = $cmaf_function_name($cmaf_when_to_call[2]);
            
            $current_representation = 0;
            $current_adaptation_set++;
        }
        
        ## Perform Cross Validation
        if($cmaf_conformance)
            $return_arr = $cmaf_function_name($cmaf_when_to_call[3]);
        if($ctawave_conformance)
            $return_arr = $ctawave_function_name($ctawave_when_to_call[1]);
        
        $current_adaptation_set = 0;
        err_file_op(2);
    }
    
    $progress_xml->allDownloadComplete = "true";
    $progress_xml->completed = "true";
    $progress_xml->completed->addAttribute('time', time());
    $progress_xml->asXml(trim($session_dir . '/' . $progress_report));
    writeEndTime((int)$progress_xml->completed->attributes());
    exit;
}

#put each line of a playlist into an array
function playlistToArray($url) {
    global $hls_manifest_type;
    $m3u8 = file_get_contents($url);
    if(!$m3u8)
        return false;
    
    $array = preg_split('/$\n?^/m', trim($m3u8), NULL, PREG_SPLIT_NO_EMPTY);
    if($array[0]!= '#EXTM3U')
        return false;
    else{
        if(strpos($m3u8, 'EXT-X-STREAM-INF') !== FALSE || strpos($m3u8, 'EXT-X-I-FRAME-STREAM-INF') !== FALSE){
            $hls_manifest_type = "MasterPlaylist";
            return $array;
        }
        else {
            $hls_manifest_type = "MediaPlaylist"; 
            return $array;
        }
    }
}

//extract the urls to stream_inf, iframe and x_media playlists from master playlist and save them in separate arrays
function playlistURLs($array){
    global $mpd_url;
    
    $base_url = dirname($mpd_url);
    
    //get the unique urls of media playlists
    foreach ($array as $line) {
        $line = trim($line);
        if ($line[0] != '#') { // true just in case of checking the stream inf playlist
            //each line that is not started with '#' is a url 
            $streamURL = getAbsURL($line, $base_url);
            if(!in_array($streamURL, $StreamInfURLArray)){ //check the url not to be a duplicate
                $StreamInfURLArray[] = $streamURL;
            }
        }
        else{
            //geting the iframe playlist urls
            if(strpos($line,"EXT-X-I-FRAME-STREAM-INF") !== FALSE) {
                $IFrameURL = getURLTag($line, $base_url);
                if($IFrameURL && !in_array($IFrameURL, $IframeURLArray)){ //check the url not to be a duplicate
                    $IframeURLArray[] = $IFrameURL;
                }
            }

            //getting the x_media playlist  urls
            if(strpos($line,"EXT-X-MEDIA") !== FALSE) {
                $XMediaURL = getURLTag($line, $base_url);
                if($XMediaURL && !in_array($XMediaURL, $XMediaURLArray)){ //check the url not to be a duplicate
                    $XMediaURLArray[] = $XMediaURL;
                }
            }

            //getting the CODECS
            if(strpos($line,"CODECS") !== FALSE) {
                $sub = substr($line, strpos($line,"CODECS=")+8);
                $codecStr = substr($sub,0,strpos($sub,"\""));

                $pos = strpos($codecStr,",");
                while($pos !== FALSE) {
                    $codec = substr($codecStr,0,$pos);
                    if($codec && !in_array($codec, $CodecArray)){ //check the codec not to be a duplicate
                        $CodecArray[] = $codec;
                    }
                    $codecStr = substr($codecStr,$pos+1);
                    $pos = strpos($codecStr,",");
                }
                $codec = $codecStr;
                if($codec && !in_array($codec, $CodecArray)){ //check the codec not to be a duplicate
                    $CodecArray[] = $codec;
                }
            }
        }    
    }

    return [$StreamInfURLArray, $IframeURLArray, $XMediaURLArray, $CodecArray];
}

//returns the absolute url 
function getAbsURL($line, $base_url){
    if (isAbsoluteURL($line)) { //if absolute url
        return $line; 
    }
    else{//if relative url
        return $base_url . '/' . $line;
    }
}

//return the url that is mentioned in playlist using a tag
function getURLTag($line, $base_url){
    if (strpos($line, 'URI') !== false) {
        $sub = substr($line, strpos($line,"URI=")+5);
        $x = substr($sub,0,strpos($sub,"\"")); //get value of URI tag 
        return getAbsURL($x, $base_url);   //return the absolute url
    }
    else
        return false;
}

/*get the urls to the segments of a playlist
 *  input is the url to the playlist
 *  output is an array of segments' urls
 */
function segmentURLs($url){
    $segmentURLs = array();
    $base_url = dirname($url);
    $array = playlistToArray($url);
    
    foreach ($array as $line) {
        $line = trim($line);
        if ($line[0] != '#') {
            $segment = getAbsURL($line, $base_url);
            if(!in_array($segment, $segmentURLs)){
                $segmentURLs[] = $segment;
            }
        }
    }
    return $segmentURLs;
}

/*
 * segmentDonload downloads the segments of a playlist and returns the size of downloaded the content
 * inputs are the url to the playlist and the type of the playlist
 */
function segmentDownload($urlarray, $type, $is_dolby){
    global $session_dir, $hls_iframe_file, $hls_mdat_file, $hls_current_index, $hls_byte_range_begin, $hls_byte_range_size, $progress_xml, $progress_report;
    
    $segment_urls = array();
    $sizearray=array();
    
    if(!$urlarray)
        return [$segment_urls, $sizearray];
    
    ## Define a directory for downloading segments
    $dir = $session_dir.'/'.$type;
    mkdir($dir, 0777, true);
    
    ## Iterate over the playlists, download the segments for each one, and save the segments of each playlist into a different folder
    foreach($urlarray as $url){
        $progress_xml->Progress->CurrentRep = $hls_current_index+1;
        $progress_xml->asXml(trim($session_dir . '/' . $progress_report));
        
        // create a new folder for this playlist
        $tmpdir = $dir.'/'.$hls_current_index.'/';
        mkdir($tmpdir, 0777, true);
        
        // extract the url of the segments of a playlist
        $segmentURLs = segmentURLs($url);
        if($type == $hls_iframe_file){
            $tmparray = playlistToArray($url);
            $array = segURLs($tmparray, $segmentURLs);
            if(!$array)
                continue;
        }
        
        // download data of the playlist into the folder and return size of the downloaded content 
        $segment_urls[] = $segmentURLs;
        $is_subtitle_rep = false; // this is not used in HLS always false
        $sizearray[] = download_data($tmpdir, ($type == $hls_iframe_file) ? $array : $segmentURLs, $is_subtitle_rep, $is_dolby);
        
        rename_file($session_dir . '/' . $hls_mdat_file . '.txt', $session_dir . '/' . $type . '_' . $hls_current_index . '_' . $hls_mdat_file . '.txt');
        if($type == $hls_iframe_file){
            $hls_byte_range_begin = array();
            $hls_byte_range_size = array();
        }
        
        $hls_current_index++;
    }
    
    $hls_current_index = 0;
    return [$segment_urls, $sizearray];
}

function segURLs($tmparray,$segmentURL){
    global $hls_byte_range_begin, $hls_byte_range_size;
    $array = array();
    $i = 0;
    foreach ($tmparray as $line) { 
        if(strpos($line,"EXT-X-MAP") !== FALSE)
        {
            if (strpos($line,"@")!== FALSE ){
                $hls_byte_range_begin[]= (int)(substr($line,strpos($line,"@")+1,strlen($line)-strpos($line,"@")));
                $st = strpos($line,"BYTERANGE=")+11;
                $en = strpos($line,"@");
                $hls_byte_range_size[] = (int)(substr($line,$st, $en-$st)); 
                $array[]=$segmentURL[0]; 
            }
            else{
                if($hls_byte_range_size[$i-1]){
                    $st = strpos($line,"BYTERANGE=")+11;
                    $hls_byte_range_begin[] = $hls_byte_range_size[$i-1];
                    $hls_byte_range_size[] = (int)(substr($line,$st));
                }
                else{
                    return NULL;
                }
            }
        }
        if(strpos($line,"EXT-X-BYTERANGE") !== FALSE){
            if (strpos($line,"@")!== FALSE ){
                $hls_byte_range_begin[]= (int)(substr($line,strpos($line,"@")+1));
                $st = strpos($line,":")+1;
                $en = strpos($line,"@");
                $hls_byte_range_size[] = (int)(substr($line,$st, $en-$st)); 
                $array[]=$segmentURL[0];
            }
            else{
                if($hls_byte_range_size[$i-1]){
                    $st = strpos($line,":")+1;
                    $hls_byte_range_begin[] = $hls_byte_range_size[$i-1];
                    $hls_byte_range_size[] = (int)(substr($line,$st));
                }
                else{
                    return NULL;
                }
            }
        }
        $i++;
    }
    return $array;
}

function groupPlaylists($file_location){
    global $session_dir, $hls_media_types, $adaptation_set_template, $reprsentation_template, $progress_xml, $progress_report, $string_info;
    
    $ResultXML = $progress_xml->addChild('Results');
    $PeriodXML = $ResultXML->addChild('Period');
    
    $i = 0;
    $file_location_ind = 0;
    $period_dir = $session_dir . '/Period0';
    create_folder_in_session($period_dir);
    foreach($hls_media_types as $hls_media_type){
        foreach($hls_media_type as $sw){
            $AdaptationXML = $PeriodXML->addChild('Adaptation');
            
            $new_sw_path = str_replace('$AS$', $i, $adaptation_set_template);
            create_folder_in_session($period_dir . '/' . $new_sw_path);
            
            $j = 0;
            foreach($sw as $track){
                $RepXML = $AdaptationXML->addChild('Representation');
                $RepXML->addAttribute('id', $j + 1);
                
                if($file_location[$file_location_ind] == 'notexist'){
                    $RepXML->textContent = "notexist";
                    $file_location_ind++;
                }
                else{
                    $RepXML->textContent = $file_location[0][2];
                    $file_location_ind ++; 
                }
                
                $name = explode('_', $track);
                $pathdir = $name[0]; $pathdir_ind = $name[1];
                $track_path = $session_dir . '/' . $pathdir . '/' . $pathdir_ind;
                
                $new_track_path = str_replace(array('$AS$', '$R$'), array($i, $j), $reprsentation_template);
                
                rename_file($track_path . '.xml', $period_dir . '/' . $new_sw_path . '/' . $new_track_path . '.xml');
                rename_file($session_dir . '/' . $track .'log.txt' , $period_dir . '/' . $new_track_path . 'log.txt');
                rename_file($track_path, $period_dir . '/' . $new_track_path);
                tabulateResults($period_dir . '/' . $new_track_path . 'log.txt', 'Segment');
                
                $j++;
            }
            
            $i++;
        }
    }
    
    $progress_xml->asXml(trim($session_dir . '/' . $progress_report));
}

function formMpdFeatures(){
    global $hls_media_types, $mpd_features;
    
    $mpd_features = array();
    $mpd_features['Period'][0] = array();
    $adapt_cnt = 0;
    foreach($hls_media_types as $hls_media_type){
        foreach($hls_media_type as $codec => $adaptation_set){
            $mpd_features['Period'][0]['AdaptationSet'][$adapt_cnt] = array();
            $mpd_features['Period'][0]['AdaptationSet'][$adapt_cnt]['codec'] = $codec;
            
            $rep_count = 0;
            foreach($adaptation_set as $representation){
                $mpd_features['Period'][0]['AdaptationSet'][$adapt_cnt]['Representation'][$rep_count] = array();
                
                $rep_count++;
            }
            $adapt_cnt++;
        }
    }
}

function determineMediaType($path, $tag){
    global $hls_media_types, $hls_iframe_file;
    
    if(file_exists($path)){
        $xml = get_DOM($path, 'atomlist');
        if($xml){
            $hdlr = $xml->getElementsByTagName('hdlr')->item(0);
            $hdlr_type = $hdlr->getAttribute('handler_type');
            $sdType = $xml->getElementsByTagName($hdlr_type.'_sampledescription')->item(0)->getAttribute('sdType');

            switch($hdlr_type){
                case 'vide':
                    if(strpos($tag, $hls_iframe_file) === FALSE)
                        $hls_media_types['video'][$sdType][] = $tag;
                    else
                        $hls_media_types['iframe'][$sdType][] = $tag;
                    break;
                case 'soun':
                    $hls_media_types['audio'][$sdType][] = $tag;
                    break;
                case 'subt':
                    $hls_media_types['subtitle'][$sdType][] = $tag;
                    break;
                default:
                    $hls_media_types['unknown'][$sdType][] = $tag;
                    break;
            }
        }
        else{
            $hls_media_types['unknown'][$sdType][] = $tag;
        }
    }
}