ILIAS  release_5-3 Revision v5.3.23-19-g915713cf615
Public Member Functions | Static Public Member Functions | Data Fields | Private Member Functions
getid3_mpeg Class Reference
+ Inheritance diagram for getid3_mpeg:
+ Collaboration diagram for getid3_mpeg:

Public Member Functions

 Analyze ()
 
- Public Member Functions inherited from getid3_handler
 __construct (getID3 $getid3, $call_module=null)
 
 Analyze ()
 
 AnalyzeString ($string)
 
 setStringMode ($string)
 
 saveAttachment ($name, $offset, $length, $image_mime=null)
 

Static Public Member Functions

static systemNonOverheadPercentage ($VideoBitrate, $AudioBitrate)
 
static videoFramerateLookup ($rawframerate)
 
static videoAspectRatioLookup ($rawaspectratio)
 
static videoAspectRatioTextLookup ($rawaspectratio)
 
static videoFormatTextLookup ($video_format)
 
static scalableModeTextLookup ($scalable_mode)
 
static pictureStructureTextLookup ($picture_structure)
 
static chromaFormatTextLookup ($chroma_format)
 

Data Fields

const START_CODE_BASE = "\x00\x00\x01"
 
const VIDEO_PICTURE_START = "\x00\x00\x01\x00"
 
const VIDEO_USER_DATA_START = "\x00\x00\x01\xB2"
 
const VIDEO_SEQUENCE_HEADER = "\x00\x00\x01\xB3"
 
const VIDEO_SEQUENCE_ERROR = "\x00\x00\x01\xB4"
 
const VIDEO_EXTENSION_START = "\x00\x00\x01\xB5"
 
const VIDEO_SEQUENCE_END = "\x00\x00\x01\xB7"
 
const VIDEO_GROUP_START = "\x00\x00\x01\xB8"
 
const AUDIO_START = "\x00\x00\x01\xC0"
 

Private Member Functions

 readBitsFromStream (&$bitstream, &$bitstreamoffset, $bits_to_read, $return_singlebit_as_boolean=true)
 

Additional Inherited Members

- Protected Member Functions inherited from getid3_handler
 ftell ()
 
 fread ($bytes)
 
 fseek ($bytes, $whence=SEEK_SET)
 
 feof ()
 
 isDependencyFor ($module)
 
 error ($text)
 
 warning ($text)
 
 notice ($text)
 
- Protected Attributes inherited from getid3_handler
 $getid3
 
 $data_string_flag = false
 
 $data_string = ''
 
 $data_string_position = 0
 
 $data_string_length = 0
 

Detailed Description

Definition at line 19 of file module.audio-video.mpeg.php.

Member Function Documentation

◆ Analyze()

getid3_mpeg::Analyze ( )

Reimplemented from getid3_handler.

Definition at line 32 of file module.audio-video.mpeg.php.

32 {
33 $info = &$this->getid3->info;
34
35 $info['fileformat'] = 'mpeg';
36 $this->fseek($info['avdataoffset']);
37
38 $MPEGstreamData = $this->fread($this->getid3->option_fread_buffer_size);
39 $MPEGstreamBaseOffset = 0; // how far are we from the beginning of the file data ($info['avdataoffset'])
40 $MPEGstreamDataOffset = 0; // how far are we from the beginning of the buffer data (~32kB)
41
42 $StartCodeValue = false;
43 $prevStartCodeValue = false;
44
45 $GOPcounter = -1;
46 $FramesByGOP = array();
47 $ParsedAVchannels = array();
48
49 do {
50//echo $MPEGstreamDataOffset.' vs '.(strlen($MPEGstreamData) - 1024).'<Br>';
51 if ($MPEGstreamDataOffset > (strlen($MPEGstreamData) - 16384)) {
52 // buffer running low, get more data
53//echo 'reading more data<br>';
54 $MPEGstreamData .= $this->fread($this->getid3->option_fread_buffer_size);
55 if (strlen($MPEGstreamData) > $this->getid3->option_fread_buffer_size) {
56 $MPEGstreamData = substr($MPEGstreamData, $MPEGstreamDataOffset);
57 $MPEGstreamBaseOffset += $MPEGstreamDataOffset;
58 $MPEGstreamDataOffset = 0;
59 }
60 }
61 if (($StartCodeOffset = strpos($MPEGstreamData, self::START_CODE_BASE, $MPEGstreamDataOffset)) === false) {
62//echo 'no more start codes found.<br>';
63 break;
64 } else {
65 $MPEGstreamDataOffset = $StartCodeOffset;
66 $prevStartCodeValue = $StartCodeValue;
67 $StartCodeValue = ord(substr($MPEGstreamData, $StartCodeOffset + 3, 1));
68//echo 'Found "'.strtoupper(dechex($StartCodeValue)).'" at offset '.($MPEGstreamBaseOffset + $StartCodeOffset).' ($MPEGstreamDataOffset = '.$MPEGstreamDataOffset.')<br>';
69 }
70 $MPEGstreamDataOffset += 4;
71 switch ($StartCodeValue) {
72
73 case 0x00: // picture_start_code
74 if (!empty($info['mpeg']['video']['bitrate_mode']) && ($info['mpeg']['video']['bitrate_mode'] == 'vbr')) {
75 $bitstream = getid3_lib::BigEndian2Bin(substr($MPEGstreamData, $StartCodeOffset + 4, 4));
76 $bitstreamoffset = 0;
77
78 $PictureHeader = array();
79
80 $PictureHeader['temporal_reference'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 10); // 10-bit unsigned integer associated with each input picture. It is incremented by one, modulo 1024, for each input frame. When a frame is coded as two fields the temporal reference in the picture header of both fields is the same. Following a group start header the temporal reference of the earliest picture (in display order) shall be reset to zero.
81 $PictureHeader['picture_coding_type'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 3); // 3 bits for picture_coding_type
82 $PictureHeader['vbv_delay'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 16); // 16 bits for vbv_delay
83 //... etc
84
85 $FramesByGOP[$GOPcounter][] = $PictureHeader;
86 }
87 break;
88
89 case 0xB3: // sequence_header_code
90 /*
91 Note: purposely doing the less-pretty (and probably a bit slower) method of using string of bits rather than bitwise operations.
92 Mostly because PHP 32-bit doesn't handle unsigned integers well for bitwise operation.
93 Also the MPEG stream is designed as a bitstream and often doesn't align nicely with byte boundaries.
94 */
95 $info['video']['codec'] = 'MPEG-1'; // will be updated if extension_start_code found
96
97 $bitstream = getid3_lib::BigEndian2Bin(substr($MPEGstreamData, $StartCodeOffset + 4, 8));
98 $bitstreamoffset = 0;
99
100 $info['mpeg']['video']['raw']['horizontal_size_value'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 12); // 12 bits for horizontal frame size. Note: horizontal_size_extension, if present, will add 2 most-significant bits to this value
101 $info['mpeg']['video']['raw']['vertical_size_value'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 12); // 12 bits for vertical frame size. Note: vertical_size_extension, if present, will add 2 most-significant bits to this value
102 $info['mpeg']['video']['raw']['aspect_ratio_information'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 4); // 4 bits for aspect_ratio_information
103 $info['mpeg']['video']['raw']['frame_rate_code'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 4); // 4 bits for Frame Rate id code
104 $info['mpeg']['video']['raw']['bitrate'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 18); // 18 bits for bit_rate_value (18 set bits = VBR, otherwise bitrate = this value * 400)
105 $marker_bit = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // The term "marker_bit" indicates a one bit field in which the value zero is forbidden. These marker bits are introduced at several points in the syntax to avoid start code emulation.
106 $info['mpeg']['video']['raw']['vbv_buffer_size'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 10); // 10 bits vbv_buffer_size_value
107 $info['mpeg']['video']['raw']['constrained_param_flag'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: constrained_param_flag
108 $info['mpeg']['video']['raw']['load_intra_quantiser_matrix'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: load_intra_quantiser_matrix
109
110 if ($info['mpeg']['video']['raw']['load_intra_quantiser_matrix']) {
111 $bitstream .= getid3_lib::BigEndian2Bin(substr($MPEGstreamData, $StartCodeOffset + 12, 64));
112 for ($i = 0; $i < 64; $i++) {
113 $info['mpeg']['video']['raw']['intra_quantiser_matrix'][$i] = self::readBitsFromStream($bitstream, $bitstreamoffset, 8);
114 }
115 }
116 $info['mpeg']['video']['raw']['load_non_intra_quantiser_matrix'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1);
117
118 if ($info['mpeg']['video']['raw']['load_non_intra_quantiser_matrix']) {
119 $bitstream .= getid3_lib::BigEndian2Bin(substr($MPEGstreamData, $StartCodeOffset + 12 + ($info['mpeg']['video']['raw']['load_intra_quantiser_matrix'] ? 64 : 0), 64));
120 for ($i = 0; $i < 64; $i++) {
121 $info['mpeg']['video']['raw']['non_intra_quantiser_matrix'][$i] = self::readBitsFromStream($bitstream, $bitstreamoffset, 8);
122 }
123 }
124
125 $info['mpeg']['video']['pixel_aspect_ratio'] = self::videoAspectRatioLookup($info['mpeg']['video']['raw']['aspect_ratio_information']);
126 $info['mpeg']['video']['pixel_aspect_ratio_text'] = self::videoAspectRatioTextLookup($info['mpeg']['video']['raw']['aspect_ratio_information']);
127 $info['mpeg']['video']['frame_rate'] = self::videoFramerateLookup($info['mpeg']['video']['raw']['frame_rate_code']);
128 if ($info['mpeg']['video']['raw']['bitrate'] == 0x3FFFF) { // 18 set bits = VBR
129 //$this->warning('This version of getID3() ['.$this->getid3->version().'] cannot determine average bitrate of VBR MPEG video files');
130 $info['mpeg']['video']['bitrate_mode'] = 'vbr';
131 } else {
132 $info['mpeg']['video']['bitrate'] = $info['mpeg']['video']['raw']['bitrate'] * 400;
133 $info['mpeg']['video']['bitrate_mode'] = 'cbr';
134 $info['video']['bitrate'] = $info['mpeg']['video']['bitrate'];
135 }
136 $info['video']['resolution_x'] = $info['mpeg']['video']['raw']['horizontal_size_value'];
137 $info['video']['resolution_y'] = $info['mpeg']['video']['raw']['vertical_size_value'];
138 $info['video']['frame_rate'] = $info['mpeg']['video']['frame_rate'];
139 $info['video']['bitrate_mode'] = $info['mpeg']['video']['bitrate_mode'];
140 $info['video']['pixel_aspect_ratio'] = $info['mpeg']['video']['pixel_aspect_ratio'];
141 $info['video']['lossless'] = false;
142 $info['video']['bits_per_sample'] = 24;
143 break;
144
145 case 0xB5: // extension_start_code
146 $info['video']['codec'] = 'MPEG-2';
147
148 $bitstream = getid3_lib::BigEndian2Bin(substr($MPEGstreamData, $StartCodeOffset + 4, 8)); // 48 bits for Sequence Extension ID; 61 bits for Sequence Display Extension ID; 59 bits for Sequence Scalable Extension ID
149 $bitstreamoffset = 0;
150
151 $info['mpeg']['video']['raw']['extension_start_code_identifier'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 4); // 4 bits for extension_start_code_identifier
152//echo $info['mpeg']['video']['raw']['extension_start_code_identifier'].'<br>';
153 switch ($info['mpeg']['video']['raw']['extension_start_code_identifier']) {
154 case 1: // 0001 Sequence Extension ID
155 $info['mpeg']['video']['raw']['profile_and_level_indication'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 8); // 8 bits for profile_and_level_indication
156 $info['mpeg']['video']['raw']['progressive_sequence'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: progressive_sequence
157 $info['mpeg']['video']['raw']['chroma_format'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 2); // 2 bits for chroma_format
158 $info['mpeg']['video']['raw']['horizontal_size_extension'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 2); // 2 bits for horizontal_size_extension
159 $info['mpeg']['video']['raw']['vertical_size_extension'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 2); // 2 bits for vertical_size_extension
160 $info['mpeg']['video']['raw']['bit_rate_extension'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 12); // 12 bits for bit_rate_extension
161 $marker_bit = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // The term "marker_bit" indicates a one bit field in which the value zero is forbidden. These marker bits are introduced at several points in the syntax to avoid start code emulation.
162 $info['mpeg']['video']['raw']['vbv_buffer_size_extension'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 8); // 8 bits for vbv_buffer_size_extension
163 $info['mpeg']['video']['raw']['low_delay'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: low_delay
164 $info['mpeg']['video']['raw']['frame_rate_extension_n'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 2); // 2 bits for frame_rate_extension_n
165 $info['mpeg']['video']['raw']['frame_rate_extension_d'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 5); // 5 bits for frame_rate_extension_d
166
167 $info['video']['resolution_x'] = ($info['mpeg']['video']['raw']['horizontal_size_extension'] << 12) | $info['mpeg']['video']['raw']['horizontal_size_value'];
168 $info['video']['resolution_y'] = ($info['mpeg']['video']['raw']['vertical_size_extension'] << 12) | $info['mpeg']['video']['raw']['vertical_size_value'];
169 $info['video']['interlaced'] = !$info['mpeg']['video']['raw']['progressive_sequence'];
170 $info['mpeg']['video']['interlaced'] = !$info['mpeg']['video']['raw']['progressive_sequence'];
171 $info['mpeg']['video']['chroma_format'] = self::chromaFormatTextLookup($info['mpeg']['video']['raw']['chroma_format']);
172 break;
173
174 case 2: // 0010 Sequence Display Extension ID
175 $info['mpeg']['video']['raw']['video_format'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 3); // 3 bits for video_format
176 $info['mpeg']['video']['raw']['colour_description'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: colour_description
177 if ($info['mpeg']['video']['raw']['colour_description']) {
178 $info['mpeg']['video']['raw']['colour_primaries'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 8); // 8 bits for colour_primaries
179 $info['mpeg']['video']['raw']['transfer_characteristics'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 8); // 8 bits for transfer_characteristics
180 $info['mpeg']['video']['raw']['matrix_coefficients'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 8); // 8 bits for matrix_coefficients
181 }
182 $info['mpeg']['video']['raw']['display_horizontal_size'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 14); // 14 bits for display_horizontal_size
183 $marker_bit = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // The term "marker_bit" indicates a one bit field in which the value zero is forbidden. These marker bits are introduced at several points in the syntax to avoid start code emulation.
184 $info['mpeg']['video']['raw']['display_vertical_size'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 14); // 14 bits for display_vertical_size
185
186 $info['mpeg']['video']['video_format'] = self::videoFormatTextLookup($info['mpeg']['video']['raw']['video_format']);
187 break;
188
189 case 3: // 0011 Quant Matrix Extension ID
190 break;
191
192 case 5: // 0101 Sequence Scalable Extension ID
193 $info['mpeg']['video']['raw']['scalable_mode'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 2); // 2 bits for scalable_mode
194 $info['mpeg']['video']['raw']['layer_id'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 4); // 4 bits for layer_id
195 if ($info['mpeg']['video']['raw']['scalable_mode'] == 1) { // "spatial scalability"
196 $info['mpeg']['video']['raw']['lower_layer_prediction_horizontal_size'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 14); // 14 bits for lower_layer_prediction_horizontal_size
197 $marker_bit = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // The term "marker_bit" indicates a one bit field in which the value zero is forbidden. These marker bits are introduced at several points in the syntax to avoid start code emulation.
198 $info['mpeg']['video']['raw']['lower_layer_prediction_vertical_size'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 14); // 14 bits for lower_layer_prediction_vertical_size
199 $info['mpeg']['video']['raw']['horizontal_subsampling_factor_m'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 5); // 5 bits for horizontal_subsampling_factor_m
200 $info['mpeg']['video']['raw']['horizontal_subsampling_factor_n'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 5); // 5 bits for horizontal_subsampling_factor_n
201 $info['mpeg']['video']['raw']['vertical_subsampling_factor_m'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 5); // 5 bits for vertical_subsampling_factor_m
202 $info['mpeg']['video']['raw']['vertical_subsampling_factor_n'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 5); // 5 bits for vertical_subsampling_factor_n
203 } elseif ($info['mpeg']['video']['raw']['scalable_mode'] == 3) { // "temporal scalability"
204 $info['mpeg']['video']['raw']['picture_mux_enable'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: picture_mux_enable
205 if ($info['mpeg']['video']['raw']['picture_mux_enable']) {
206 $info['mpeg']['video']['raw']['mux_to_progressive_sequence'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: mux_to_progressive_sequence
207 }
208 $info['mpeg']['video']['raw']['picture_mux_order'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 3); // 3 bits for picture_mux_order
209 $info['mpeg']['video']['raw']['picture_mux_factor'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 3); // 3 bits for picture_mux_factor
210 }
211
212 $info['mpeg']['video']['scalable_mode'] = self::scalableModeTextLookup($info['mpeg']['video']['raw']['scalable_mode']);
213 break;
214
215 case 7: // 0111 Picture Display Extension ID
216 break;
217
218 case 8: // 1000 Picture Coding Extension ID
219 $info['mpeg']['video']['raw']['f_code_00'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 4); // 4 bits for f_code[0][0] (forward horizontal)
220 $info['mpeg']['video']['raw']['f_code_01'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 4); // 4 bits for f_code[0][1] (forward vertical)
221 $info['mpeg']['video']['raw']['f_code_10'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 4); // 4 bits for f_code[1][0] (backward horizontal)
222 $info['mpeg']['video']['raw']['f_code_11'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 4); // 4 bits for f_code[1][1] (backward vertical)
223 $info['mpeg']['video']['raw']['intra_dc_precision'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 2); // 2 bits for intra_dc_precision
224 $info['mpeg']['video']['raw']['picture_structure'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 2); // 2 bits for picture_structure
225 $info['mpeg']['video']['raw']['top_field_first'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: top_field_first
226 $info['mpeg']['video']['raw']['frame_pred_frame_dct'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: frame_pred_frame_dct
227 $info['mpeg']['video']['raw']['concealment_motion_vectors'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: concealment_motion_vectors
228 $info['mpeg']['video']['raw']['q_scale_type'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: q_scale_type
229 $info['mpeg']['video']['raw']['intra_vlc_format'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: intra_vlc_format
230 $info['mpeg']['video']['raw']['alternate_scan'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: alternate_scan
231 $info['mpeg']['video']['raw']['repeat_first_field'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: repeat_first_field
232 $info['mpeg']['video']['raw']['chroma_420_type'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: chroma_420_type
233 $info['mpeg']['video']['raw']['progressive_frame'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: progressive_frame
234 $info['mpeg']['video']['raw']['composite_display_flag'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: composite_display_flag
235 if ($info['mpeg']['video']['raw']['composite_display_flag']) {
236 $info['mpeg']['video']['raw']['v_axis'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: v_axis
237 $info['mpeg']['video']['raw']['field_sequence'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 3); // 3 bits for field_sequence
238 $info['mpeg']['video']['raw']['sub_carrier'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: sub_carrier
239 $info['mpeg']['video']['raw']['burst_amplitude'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 7); // 7 bits for burst_amplitude
240 $info['mpeg']['video']['raw']['sub_carrier_phase'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 8); // 8 bits for sub_carrier_phase
241 }
242
243 $info['mpeg']['video']['intra_dc_precision_bits'] = $info['mpeg']['video']['raw']['intra_dc_precision'] + 8;
244 $info['mpeg']['video']['picture_structure'] = self::pictureStructureTextLookup($info['mpeg']['video']['raw']['picture_structure']);
245 break;
246
247 case 9: // 1001 Picture Spatial Scalable Extension ID
248 break;
249 case 10: // 1010 Picture Temporal Scalable Extension ID
250 break;
251
252 default:
253 $this->warning('Unexpected $info[mpeg][video][raw][extension_start_code_identifier] value of '.$info['mpeg']['video']['raw']['extension_start_code_identifier']);
254 break;
255 }
256 break;
257
258
259 case 0xB8: // group_of_pictures_header
260 $GOPcounter++;
261 if ($info['mpeg']['video']['bitrate_mode'] == 'vbr') {
262 $bitstream = getid3_lib::BigEndian2Bin(substr($MPEGstreamData, $StartCodeOffset + 4, 4)); // 27 bits needed for group_of_pictures_header
263 $bitstreamoffset = 0;
264
265 $GOPheader = array();
266
267 $GOPheader['byte_offset'] = $MPEGstreamBaseOffset + $StartCodeOffset;
268 $GOPheader['drop_frame_flag'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: drop_frame_flag
269 $GOPheader['time_code_hours'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 5); // 5 bits for time_code_hours
270 $GOPheader['time_code_minutes'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 6); // 6 bits for time_code_minutes
271 $marker_bit = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // The term "marker_bit" indicates a one bit field in which the value zero is forbidden. These marker bits are introduced at several points in the syntax to avoid start code emulation.
272 $GOPheader['time_code_seconds'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 6); // 6 bits for time_code_seconds
273 $GOPheader['time_code_pictures'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 6); // 6 bits for time_code_pictures
274 $GOPheader['closed_gop'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: closed_gop
275 $GOPheader['broken_link'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: broken_link
276
277 $time_code_separator = ($GOPheader['drop_frame_flag'] ? ';' : ':'); // While non-drop time code is displayed with colons separating the digit pairs—"HH:MM:SS:FF"—drop frame is usually represented with a semi-colon (;) or period (.) as the divider between all the digit pairs—"HH;MM;SS;FF", "HH.MM.SS.FF"
278 $GOPheader['time_code'] = sprintf('%02d'.$time_code_separator.'%02d'.$time_code_separator.'%02d'.$time_code_separator.'%02d', $GOPheader['time_code_hours'], $GOPheader['time_code_minutes'], $GOPheader['time_code_seconds'], $GOPheader['time_code_pictures']);
279
280 $info['mpeg']['group_of_pictures'][] = $GOPheader;
281 }
282 break;
283
284 case 0xC0: // audio stream
285 case 0xC1: // audio stream
286 case 0xC2: // audio stream
287 case 0xC3: // audio stream
288 case 0xC4: // audio stream
289 case 0xC5: // audio stream
290 case 0xC6: // audio stream
291 case 0xC7: // audio stream
292 case 0xC8: // audio stream
293 case 0xC9: // audio stream
294 case 0xCA: // audio stream
295 case 0xCB: // audio stream
296 case 0xCC: // audio stream
297 case 0xCD: // audio stream
298 case 0xCE: // audio stream
299 case 0xCF: // audio stream
300 case 0xD0: // audio stream
301 case 0xD1: // audio stream
302 case 0xD2: // audio stream
303 case 0xD3: // audio stream
304 case 0xD4: // audio stream
305 case 0xD5: // audio stream
306 case 0xD6: // audio stream
307 case 0xD7: // audio stream
308 case 0xD8: // audio stream
309 case 0xD9: // audio stream
310 case 0xDA: // audio stream
311 case 0xDB: // audio stream
312 case 0xDC: // audio stream
313 case 0xDD: // audio stream
314 case 0xDE: // audio stream
315 case 0xDF: // audio stream
316 //case 0xE0: // video stream
317 //case 0xE1: // video stream
318 //case 0xE2: // video stream
319 //case 0xE3: // video stream
320 //case 0xE4: // video stream
321 //case 0xE5: // video stream
322 //case 0xE6: // video stream
323 //case 0xE7: // video stream
324 //case 0xE8: // video stream
325 //case 0xE9: // video stream
326 //case 0xEA: // video stream
327 //case 0xEB: // video stream
328 //case 0xEC: // video stream
329 //case 0xED: // video stream
330 //case 0xEE: // video stream
331 //case 0xEF: // video stream
332 if (isset($ParsedAVchannels[$StartCodeValue])) {
333 break;
334 }
335 $ParsedAVchannels[$StartCodeValue] = $StartCodeValue;
336 // http://en.wikipedia.org/wiki/Packetized_elementary_stream
337 // http://dvd.sourceforge.net/dvdinfo/pes-hdr.html
338/*
339 $PackedElementaryStream = array();
340 if ($StartCodeValue >= 0xE0) {
341 $PackedElementaryStream['stream_type'] = 'video';
342 $PackedElementaryStream['stream_id'] = $StartCodeValue - 0xE0;
343 } else {
344 $PackedElementaryStream['stream_type'] = 'audio';
345 $PackedElementaryStream['stream_id'] = $StartCodeValue - 0xC0;
346 }
347 $PackedElementaryStream['packet_length'] = getid3_lib::BigEndian2Int(substr($MPEGstreamData, $StartCodeOffset + 4, 2));
348
349 $bitstream = getid3_lib::BigEndian2Bin(substr($MPEGstreamData, $StartCodeOffset + 6, 3)); // more may be needed below
350 $bitstreamoffset = 0;
351
352 $PackedElementaryStream['marker_bits'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 2); // 2 bits for marker_bits -- should be "10" = 2
353echo 'marker_bits = '.$PackedElementaryStream['marker_bits'].'<br>';
354 $PackedElementaryStream['scrambling_control'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 2); // 2 bits for scrambling_control -- 00 implies not scrambled
355 $PackedElementaryStream['priority'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: priority
356 $PackedElementaryStream['data_alignment_indicator'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: data_alignment_indicator -- 1 indicates that the PES packet header is immediately followed by the video start code or audio syncword
357 $PackedElementaryStream['copyright'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: copyright -- 1 implies copyrighted
358 $PackedElementaryStream['original_or_copy'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: original_or_copy -- 1 implies original
359 $PackedElementaryStream['pts_flag'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: pts_flag -- Presentation Time Stamp
360 $PackedElementaryStream['dts_flag'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: dts_flag -- Decode Time Stamp
361 $PackedElementaryStream['escr_flag'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: escr_flag -- Elementary Stream Clock Reference
362 $PackedElementaryStream['es_rate_flag'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: es_rate_flag -- Elementary Stream [data] Rate
363 $PackedElementaryStream['dsm_trick_mode_flag'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: dsm_trick_mode_flag -- DSM trick mode - not used by DVD
364 $PackedElementaryStream['additional_copy_info_flag'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: additional_copy_info_flag
365 $PackedElementaryStream['crc_flag'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: crc_flag
366 $PackedElementaryStream['extension_flag'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 1); // 1 bit flag: extension_flag
367 $PackedElementaryStream['pes_remain_header_length'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 8); // 1 bit flag: priority
368
369 $additional_header_bytes = 0;
370 $additional_header_bytes += ($PackedElementaryStream['pts_flag'] ? 5 : 0);
371 $additional_header_bytes += ($PackedElementaryStream['dts_flag'] ? 5 : 0);
372 $additional_header_bytes += ($PackedElementaryStream['escr_flag'] ? 6 : 0);
373 $additional_header_bytes += ($PackedElementaryStream['es_rate_flag'] ? 3 : 0);
374 $additional_header_bytes += ($PackedElementaryStream['additional_copy_info_flag'] ? 1 : 0);
375 $additional_header_bytes += ($PackedElementaryStream['crc_flag'] ? 2 : 0);
376 $additional_header_bytes += ($PackedElementaryStream['extension_flag'] ? 1 : 0);
377$PackedElementaryStream['additional_header_bytes'] = $additional_header_bytes;
378 $bitstream .= getid3_lib::BigEndian2Bin(substr($MPEGstreamData, $StartCodeOffset + 9, $additional_header_bytes));
379
380 $info['mpeg']['packed_elementary_streams'][$PackedElementaryStream['stream_type']][$PackedElementaryStream['stream_id']][] = $PackedElementaryStream;
381*/
382 $getid3_temp = new getID3();
383 $getid3_temp->openfile($this->getid3->filename);
384 $getid3_temp->info = $info;
385 $getid3_mp3 = new getid3_mp3($getid3_temp);
386 for ($i = 0; $i <= 7; $i++) {
387 // some files have the MPEG-audio header 8 bytes after the end of the $00 $00 $01 $C0 signature, some have it up to 13 bytes (or more?) after
388 // I have no idea why or what the difference is, so this is a stupid hack.
389 // If anybody has any better idea of what's going on, please let me know - info@getid3.org
390 $getid3_temp->info = $info; // only overwrite real data if valid header found
391//echo 'audio at? '.($MPEGstreamBaseOffset + $StartCodeOffset + 4 + 8 + $i).'<br>';
392 if ($getid3_mp3->decodeMPEGaudioHeader($MPEGstreamBaseOffset + $StartCodeOffset + 4 + 8 + $i, $getid3_temp->info, false)) {
393//echo 'yes!<br>';
394 $info = $getid3_temp->info;
395 $info['audio']['bitrate_mode'] = 'cbr';
396 $info['audio']['lossless'] = false;
397 break;
398 }
399 }
400 unset($getid3_temp, $getid3_mp3);
401 break;
402
403 case 0xBC: // Program Stream Map
404 case 0xBD: // Private stream 1 (non MPEG audio, subpictures)
405 case 0xBE: // Padding stream
406 case 0xBF: // Private stream 2 (navigation data)
407 case 0xF0: // ECM stream
408 case 0xF1: // EMM stream
409 case 0xF2: // DSM-CC stream
410 case 0xF3: // ISO/IEC_13522_stream
411 case 0xF4: // ITU-I Rec. H.222.1 type A
412 case 0xF5: // ITU-I Rec. H.222.1 type B
413 case 0xF6: // ITU-I Rec. H.222.1 type C
414 case 0xF7: // ITU-I Rec. H.222.1 type D
415 case 0xF8: // ITU-I Rec. H.222.1 type E
416 case 0xF9: // ancilliary stream
417 case 0xFA: // ISO/IEC 14496-1 SL-packtized stream
418 case 0xFB: // ISO/IEC 14496-1 FlexMux stream
419 case 0xFC: // metadata stream
420 case 0xFD: // extended stream ID
421 case 0xFE: // reserved data stream
422 case 0xFF: // program stream directory
423 // ignore
424 break;
425
426 default:
427 // ignore
428 break;
429 }
430 } while (true);
431
432
433
434// // Temporary hack to account for interleaving overhead:
435// if (!empty($info['video']['bitrate']) && !empty($info['audio']['bitrate'])) {
436// $info['playtime_seconds'] = (($info['avdataend'] - $info['avdataoffset']) * 8) / ($info['video']['bitrate'] + $info['audio']['bitrate']);
437//
438// // Interleaved MPEG audio/video files have a certain amount of overhead that varies
439// // by both video and audio bitrates, and not in any sensible, linear/logarithmic pattern
440// // Use interpolated lookup tables to approximately guess how much is overhead, because
441// // playtime is calculated as filesize / total-bitrate
442// $info['playtime_seconds'] *= self::systemNonOverheadPercentage($info['video']['bitrate'], $info['audio']['bitrate']);
443//
444// //switch ($info['video']['bitrate']) {
445// // case('5000000'):
446// // $multiplier = 0.93292642112380355828048824319889;
447// // break;
448// // case('5500000'):
449// // $multiplier = 0.93582895375200989965359777343219;
450// // break;
451// // case('6000000'):
452// // $multiplier = 0.93796247714820932532911373859139;
453// // break;
454// // case('7000000'):
455// // $multiplier = 0.9413264083635103463010117778776;
456// // break;
457// // default:
458// // $multiplier = 1;
459// // break;
460// //}
461// //$info['playtime_seconds'] *= $multiplier;
462// //$this->warning('Interleaved MPEG audio/video playtime may be inaccurate. With current hack should be within a few seconds of accurate. Report to info@getid3.org if off by more than 10 seconds.');
463// if ($info['video']['bitrate'] < 50000) {
464// $this->warning('Interleaved MPEG audio/video playtime may be slightly inaccurate for video bitrates below 100kbps. Except in extreme low-bitrate situations, error should be less than 1%. Report to info@getid3.org if greater than this.');
465// }
466// }
467//
468/*
469$time_prev = 0;
470$byte_prev = 0;
471$vbr_bitrates = array();
472foreach ($info['mpeg']['group_of_pictures'] as $gopkey => $gopdata) {
473 $time_this = ($gopdata['time_code_hours'] * 3600) + ($gopdata['time_code_minutes'] * 60) + $gopdata['time_code_seconds'] + ($gopdata['time_code_seconds'] / 30);
474 $byte_this = $gopdata['byte_offset'];
475 if ($gopkey > 0) {
476 if ($time_this > $time_prev) {
477 $bytedelta = $byte_this - $byte_prev;
478 $timedelta = $time_this - $time_prev;
479 $this_bitrate = ($bytedelta * 8) / $timedelta;
480echo $gopkey.': ('.number_format($time_prev, 2).'-'.number_format($time_this, 2).') '.number_format($bytedelta).' bytes over '.number_format($timedelta, 3).' seconds = '.number_format($this_bitrate / 1000, 2).'kbps<br>';
481 $time_prev = $time_this;
482 $byte_prev = $byte_this;
483 $vbr_bitrates[] = $this_bitrate;
484 }
485 }
486}
487echo 'average_File_bitrate = '.number_format(array_sum($vbr_bitrates) / count($vbr_bitrates), 1).'<br>';
488*/
489//echo '<pre>'.print_r($FramesByGOP, true).'</pre>';
490 if (!empty($info['mpeg']['video']['bitrate_mode']) && ($info['mpeg']['video']['bitrate_mode'] == 'vbr')) {
491 $last_GOP_id = max(array_keys($FramesByGOP));
492 $frames_in_last_GOP = count($FramesByGOP[$last_GOP_id]);
493 $gopdata = &$info['mpeg']['group_of_pictures'][$last_GOP_id];
494 $info['playtime_seconds'] = ($gopdata['time_code_hours'] * 3600) + ($gopdata['time_code_minutes'] * 60) + $gopdata['time_code_seconds'] + (($gopdata['time_code_pictures'] + $frames_in_last_GOP + 1) / $info['mpeg']['video']['frame_rate']);
495 if (!isset($info['video']['bitrate'])) {
496 $overall_bitrate = ($info['avdataend'] - $info['avdataoffset']) * 8 / $info['playtime_seconds'];
497 $info['video']['bitrate'] = $overall_bitrate - (isset($info['audio']['bitrate']) ? $info['audio']['bitrate'] : 0);
498 }
499 unset($info['mpeg']['group_of_pictures']);
500 }
501
502 return true;
503 }
sprintf
sprintf('%.4f', $callTime)
Definition: 01pharSimple.php:87
getid3_handler\fseek
fseek($bytes, $whence=SEEK_SET)
Definition: getid3.php:1711
getid3_handler\fread
fread($bytes)
Definition: getid3.php:1683
getid3_handler\warning
warning($text)
Definition: getid3.php:1758
getid3_lib\BigEndian2Bin
static BigEndian2Bin($byteword)
Definition: getid3.lib.php:297
getid3_mp3
Definition: module.audio.mp3.php:26
getid3_mpeg\pictureStructureTextLookup
static pictureStructureTextLookup($picture_structure)
Definition: module.audio-video.mpeg.php:594
getid3_mpeg\videoFormatTextLookup
static videoFormatTextLookup($video_format)
Definition: module.audio-video.mpeg.php:582
getid3_mpeg\chromaFormatTextLookup
static chromaFormatTextLookup($chroma_format)
Definition: module.audio-video.mpeg.php:600
getid3_mpeg\readBitsFromStream
readBitsFromStream(&$bitstream, &$bitstreamoffset, $bits_to_read, $return_singlebit_as_boolean=true)
Definition: module.audio-video.mpeg.php:505
getid3_mpeg\videoAspectRatioTextLookup
static videoAspectRatioTextLookup($rawaspectratio)
Definition: module.audio-video.mpeg.php:577
getid3_mpeg\videoFramerateLookup
static videoFramerateLookup($rawframerate)
Definition: module.audio-video.mpeg.php:567
getid3_mpeg\videoAspectRatioLookup
static videoAspectRatioLookup($rawaspectratio)
Definition: module.audio-video.mpeg.php:572
getid3_mpeg\scalableModeTextLookup
static scalableModeTextLookup($scalable_mode)
Definition: module.audio-video.mpeg.php:588
$i
$i
Definition: disco.tpl.php:19
$info
$info
Definition: index.php:5

References $i, $info, getid3_lib\BigEndian2Bin(), chromaFormatTextLookup(), getid3_handler\fread(), getid3_handler\fseek(), pictureStructureTextLookup(), readBitsFromStream(), scalableModeTextLookup(), sprintf, videoAspectRatioLookup(), videoAspectRatioTextLookup(), videoFormatTextLookup(), videoFramerateLookup(), and getid3_handler\warning().

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◆ chromaFormatTextLookup()

static getid3_mpeg::chromaFormatTextLookup (   $chroma_format)
static

Definition at line 600 of file module.audio-video.mpeg.php.

600 {
601 // ISO/IEC 13818-2, section 6.3.11, Table 6-14 Meaning of picture_structure
602 $lookup = array('reserved', '4:2:0', '4:2:2', '4:4:4');
603 return (isset($lookup[$chroma_format]) ? $lookup[$chroma_format] : '');
604 }

Referenced by Analyze().

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◆ pictureStructureTextLookup()

static getid3_mpeg::pictureStructureTextLookup (   $picture_structure)
static

Definition at line 594 of file module.audio-video.mpeg.php.

594 {
595 // ISO/IEC 13818-2, section 6.3.11, Table 6-14 Meaning of picture_structure
596 $lookup = array('reserved', 'Top Field', 'Bottom Field', 'Frame picture');
597 return (isset($lookup[$picture_structure]) ? $lookup[$picture_structure] : '');
598 }

Referenced by Analyze().

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◆ readBitsFromStream()

getid3_mpeg::readBitsFromStream ( &  $bitstream,
&  $bitstreamoffset,
  $bits_to_read,
  $return_singlebit_as_boolean = true 
)
private

Definition at line 505 of file module.audio-video.mpeg.php.

505 {
506 $return = bindec(substr($bitstream, $bitstreamoffset, $bits_to_read));
507 $bitstreamoffset += $bits_to_read;
508 if (($bits_to_read == 1) && $return_singlebit_as_boolean) {
509 $return = (bool) $return;
510 }
511 return $return;
512 }

Referenced by Analyze().

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◆ scalableModeTextLookup()

static getid3_mpeg::scalableModeTextLookup (   $scalable_mode)
static

Definition at line 588 of file module.audio-video.mpeg.php.

588 {
589 // ISO/IEC 13818-2, section 6.3.8, Table 6-10. Definition of scalable_mode
590 $lookup = array('data partitioning', 'spatial scalability', 'SNR scalability', 'temporal scalability');
591 return (isset($lookup[$scalable_mode]) ? $lookup[$scalable_mode] : '');
592 }

Referenced by Analyze().

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◆ systemNonOverheadPercentage()

static getid3_mpeg::systemNonOverheadPercentage (   $VideoBitrate,
  $AudioBitrate 
)
static

Definition at line 515 of file module.audio-video.mpeg.php.

515 {
516 $OverheadPercentage = 0;
517
518 $AudioBitrate = max(min($AudioBitrate / 1000, 384), 32); // limit to range of 32kbps - 384kbps (should be only legal bitrates, but maybe VBR?)
519 $VideoBitrate = max(min($VideoBitrate / 1000, 10000), 10); // limit to range of 10kbps - 10Mbps (beyond that curves flatten anyways, no big loss)
520
521
522 //OMBB[audiobitrate] = array(video-10kbps, video-100kbps, video-1000kbps, video-10000kbps)
523 $OverheadMultiplierByBitrate[32] = array(0, 0.9676287944368530, 0.9802276264360310, 0.9844916183244460, 0.9852821845179940);
524 $OverheadMultiplierByBitrate[48] = array(0, 0.9779100089209830, 0.9787770035359320, 0.9846738664076130, 0.9852683013799960);
525 $OverheadMultiplierByBitrate[56] = array(0, 0.9731249855367600, 0.9776624308938040, 0.9832606361852130, 0.9843922606633340);
526 $OverheadMultiplierByBitrate[64] = array(0, 0.9755642683275760, 0.9795256705493390, 0.9836573009193170, 0.9851122539404470);
527 $OverheadMultiplierByBitrate[96] = array(0, 0.9788025247497290, 0.9798553314148700, 0.9822956869792560, 0.9834815119124690);
528 $OverheadMultiplierByBitrate[128] = array(0, 0.9816940050925480, 0.9821675936072120, 0.9829756927470870, 0.9839763420152050);
529 $OverheadMultiplierByBitrate[160] = array(0, 0.9825894094561180, 0.9820913399073960, 0.9823907143253970, 0.9832821783651570);
530 $OverheadMultiplierByBitrate[192] = array(0, 0.9832038474336260, 0.9825731694317960, 0.9821028622712400, 0.9828262076447620);
531 $OverheadMultiplierByBitrate[224] = array(0, 0.9836516298538770, 0.9824718601823890, 0.9818302180625380, 0.9823735101626480);
532 $OverheadMultiplierByBitrate[256] = array(0, 0.9845863022094920, 0.9837229411967540, 0.9824521662210830, 0.9828645172100790);
533 $OverheadMultiplierByBitrate[320] = array(0, 0.9849565280263180, 0.9837683142805110, 0.9822885275960400, 0.9824424382727190);
534 $OverheadMultiplierByBitrate[384] = array(0, 0.9856094774357600, 0.9844573394432720, 0.9825970399837330, 0.9824673808303890);
535
536 $BitrateToUseMin = 32;
537 $BitrateToUseMax = 32;
538 $previousBitrate = 32;
539 foreach ($OverheadMultiplierByBitrate as $key => $value) {
540 if ($AudioBitrate >= $previousBitrate) {
541 $BitrateToUseMin = $previousBitrate;
542 }
543 if ($AudioBitrate < $key) {
544 $BitrateToUseMax = $key;
545 break;
546 }
547 $previousBitrate = $key;
548 }
549 $FactorA = ($BitrateToUseMax - $AudioBitrate) / ($BitrateToUseMax - $BitrateToUseMin);
550
551 $VideoBitrateLog10 = log10($VideoBitrate);
552 $VideoFactorMin1 = $OverheadMultiplierByBitrate[$BitrateToUseMin][floor($VideoBitrateLog10)];
553 $VideoFactorMin2 = $OverheadMultiplierByBitrate[$BitrateToUseMax][floor($VideoBitrateLog10)];
554 $VideoFactorMax1 = $OverheadMultiplierByBitrate[$BitrateToUseMin][ceil($VideoBitrateLog10)];
555 $VideoFactorMax2 = $OverheadMultiplierByBitrate[$BitrateToUseMax][ceil($VideoBitrateLog10)];
556 $FactorV = $VideoBitrateLog10 - floor($VideoBitrateLog10);
557
558 $OverheadPercentage = $VideoFactorMin1 * $FactorA * $FactorV;
559 $OverheadPercentage += $VideoFactorMin2 * (1 - $FactorA) * $FactorV;
560 $OverheadPercentage += $VideoFactorMax1 * $FactorA * (1 - $FactorV);
561 $OverheadPercentage += $VideoFactorMax2 * (1 - $FactorA) * (1 - $FactorV);
562
563 return $OverheadPercentage;
564 }
$key
$key
Definition: croninfo.php:18

References $key.

◆ videoAspectRatioLookup()

static getid3_mpeg::videoAspectRatioLookup (   $rawaspectratio)
static

Definition at line 572 of file module.audio-video.mpeg.php.

572 {
573 $lookup = array(0, 1, 0.6735, 0.7031, 0.7615, 0.8055, 0.8437, 0.8935, 0.9157, 0.9815, 1.0255, 1.0695, 1.0950, 1.1575, 1.2015, 0);
574 return (isset($lookup[$rawaspectratio]) ? (float) $lookup[$rawaspectratio] : (float) 0);
575 }

Referenced by Analyze().

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◆ videoAspectRatioTextLookup()

static getid3_mpeg::videoAspectRatioTextLookup (   $rawaspectratio)
static

Definition at line 577 of file module.audio-video.mpeg.php.

577 {
578 $lookup = array('forbidden', 'square pixels', '0.6735', '16:9, 625 line, PAL', '0.7615', '0.8055', '16:9, 525 line, NTSC', '0.8935', '4:3, 625 line, PAL, CCIR601', '0.9815', '1.0255', '1.0695', '4:3, 525 line, NTSC, CCIR601', '1.1575', '1.2015', 'reserved');
579 return (isset($lookup[$rawaspectratio]) ? $lookup[$rawaspectratio] : '');
580 }

Referenced by Analyze().

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◆ videoFormatTextLookup()

static getid3_mpeg::videoFormatTextLookup (   $video_format)
static

Definition at line 582 of file module.audio-video.mpeg.php.

582 {
583 // ISO/IEC 13818-2, section 6.3.6, Table 6-6. Meaning of video_format
584 $lookup = array('component', 'PAL', 'NTSC', 'SECAM', 'MAC', 'Unspecified video format', 'reserved(6)', 'reserved(7)');
585 return (isset($lookup[$video_format]) ? $lookup[$video_format] : '');
586 }

Referenced by Analyze().

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◆ videoFramerateLookup()

static getid3_mpeg::videoFramerateLookup (   $rawframerate)
static

Definition at line 567 of file module.audio-video.mpeg.php.

567 {
568 $lookup = array(0, 23.976, 24, 25, 29.97, 30, 50, 59.94, 60);
569 return (isset($lookup[$rawframerate]) ? (float) $lookup[$rawframerate] : (float) 0);
570 }

Referenced by Analyze().

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Field Documentation

◆ AUDIO_START

const getid3_mpeg::AUDIO_START = "\x00\x00\x01\xC0"

Definition at line 29 of file module.audio-video.mpeg.php.

◆ START_CODE_BASE

const getid3_mpeg::START_CODE_BASE = "\x00\x00\x01"

Definition at line 21 of file module.audio-video.mpeg.php.

◆ VIDEO_EXTENSION_START

const getid3_mpeg::VIDEO_EXTENSION_START = "\x00\x00\x01\xB5"

Definition at line 26 of file module.audio-video.mpeg.php.

◆ VIDEO_GROUP_START

const getid3_mpeg::VIDEO_GROUP_START = "\x00\x00\x01\xB8"

Definition at line 28 of file module.audio-video.mpeg.php.

◆ VIDEO_PICTURE_START

const getid3_mpeg::VIDEO_PICTURE_START = "\x00\x00\x01\x00"

Definition at line 22 of file module.audio-video.mpeg.php.

◆ VIDEO_SEQUENCE_END

const getid3_mpeg::VIDEO_SEQUENCE_END = "\x00\x00\x01\xB7"

Definition at line 27 of file module.audio-video.mpeg.php.

◆ VIDEO_SEQUENCE_ERROR

const getid3_mpeg::VIDEO_SEQUENCE_ERROR = "\x00\x00\x01\xB4"

Definition at line 25 of file module.audio-video.mpeg.php.

◆ VIDEO_SEQUENCE_HEADER

const getid3_mpeg::VIDEO_SEQUENCE_HEADER = "\x00\x00\x01\xB3"

Definition at line 24 of file module.audio-video.mpeg.php.

◆ VIDEO_USER_DATA_START

const getid3_mpeg::VIDEO_USER_DATA_START = "\x00\x00\x01\xB2"

Definition at line 23 of file module.audio-video.mpeg.php.

The documentation for this class was generated from the following file: