ParseDIVXTAG example

case 'AMV ':
                            unset($info['riff']);
                            $info['amv'] = $this->ParseRIFFAMV($chunkdata['offset'] + 4, $nextRIFFoffset);
                            break;

                        case 'JUNK':
                            // ignore                             $thisfile_riff[$nextRIFFheaderID][] = $chunkdata;
                            break;

                        case 'IDVX':
                            $info['divxtag']['comments'] = self::ParseDIVXTAG($this->fread($chunkdata['size']));
                            break;

                        default:
                            if ($info['filesize'] == ($chunkdata['offset'] - 8 + 128)) {
                                $DIVXTAG = $nextRIFFheader.$this->fread(128 - 12);
                                if (substr($DIVXTAG, -7) == 'DIVXTAG') {
                                    // DIVXTAG is supposed to be inside an IDVX chunk in a LIST chunk, but some bad encoders just slap it on the end of a file                                     $this->warning('Found wrongly-structured DIVXTAG at offset '.($this->ftell() - 128).', parsing anyway');
                                    $info['divxtag']['comments'] = self::ParseDIVXTAG($DIVXTAG);
                                    break 2;
                                }
                            }