$b_Mp ? 1 : -1; } /** * Return the index of the $haystack element which has the closest resolution * to $needle resolution string. * @param array $haystack * @param string $needle * @param function $access_function filters input parameters by doing something * like $a = $access_function($a). Leave it NULL for no filtering. */ function get_closest_res($haystack, $needle, $access_function = NULL) { $d_min = INF; $i_min = FALSE; foreach($haystack as $i => $elem) { if ($access_function !== NULL) $elem = $access_function($elem); $d = abs(res_to_width($elem) * res_to_height($elem) - res_to_width($needle) * res_to_height($needle)); if ($d < $d_min) { $d_min = $d; $i_min = $i; } } return $i_min; } /** * Returns information about an Audio/Video file. * * @param string $file_name Audio/Video file * @return dictionary a dictionary of audio/video properties with keys: *

*
• width
*
• height
*
• dar (display aspect ratio)
*
• duration (formated as [HH:]mm:ss)
*
• size (in bytes)
*

*/ function get_av_info($file_name) { // TODO use ffprobe to return width, height, DAR, duration and size of a video return array('width'=> 1440, 'height'=> 1080, 'dar'=> '16:9', 'duration'=> '00:10', 'size'=> 5568748); } /** * Return a dictionary with formats compliant for DB and CIS and computes * resolutions such that an uploaded video will not be converted to a higher * resolution. * * @param type $formats formats as in content_ingestion config file * @param type $av_info structure as returned by get_av_info function from this * helper * @param type $elim_dupl_res eliminate consecutive formats with the same * resolution * @return array a dictionary with DB format at key 'db_formats' and CIS format * at key 'transcode_configs' */ function prepare_formats($formats, $av_info, $elim_dupl_res=FALSE) { $transcode_configs = array(); $db_formats = array(); for ($i = 0; $i < count($formats); $i++) { $transcode_configs[$i]['container'] = $formats[$i]['container']; $transcode_configs[$i]['extension'] = $formats[$i]['extension']; $db_formats[$i]['ext'] = $formats[$i]['extension']; $transcode_configs[$i]['a_codec'] = $formats[$i]['audio_codec']; $transcode_configs[$i]['a_bitrate'] = $formats[$i]['audio_bit_rate']; $transcode_configs[$i]['a_samplingrate'] = $formats[$i]['audio_sampling_rate']; $transcode_configs[$i]['a_channels'] = $formats[$i]['audio_channels']; $transcode_configs[$i]['v_codec'] = $formats[$i]['video_codec']; $transcode_configs[$i]['v_bitrate'] = $formats[$i]['video_bit_rate']; $transcode_configs[$i]['v_framerate'] = $formats[$i]['video_frame_rate']; $transcode_configs[$i]['v_dar'] = $av_info['dar']; $db_formats[$i]['dar'] = $av_info['dar']; $sar = $av_info['width'] / $av_info['height']; if ($av_info['height'] < $formats[$i]['video_height']) { $width = $av_info['width']; $height = $av_info['height']; } else { $height = $formats[$i]['video_height']; $width = round($sar * $height); } $transcode_configs[$i]['v_resolution'] = "${width}x${height}"; $db_formats[$i]['res'] = "${width}x${height}"; } // Eliminate formats with duplicate resolutions. if ($elim_dupl_res) { for ($i = 1; $i < count($transcode_configs); $i++) { if ($transcode_configs[$i]['v_resolution'] === $transcode_configs[$i - 1]['v_resolution']) { unset($transcode_configs[$i - 1]); unset($db_formats[$i - 1]); $i--; } } } return array('transcode_configs'=>$transcode_configs, 'db_formats'=>$db_formats); } /* End of file video_helper.php */ /* Location: ./application/helpers/video_helper.php */