1: <?php
2: /////////////////////////////////////////////////////////////////
3: /// getID3() by James Heinrich <info@getid3.org> //
4: // available at http://getid3.sourceforge.net //
5: // or http://www.getid3.org //
6: // also https://github.com/JamesHeinrich/getID3 //
7: /////////////////////////////////////////////////////////////////
8: // See readme.txt for more details //
9: /////////////////////////////////////////////////////////////////
10: // //
11: // module.audio-video.mpeg.php //
12: // module for analyzing MPEG files //
13: // dependencies: module.audio.mp3.php //
14: // ///
15: /////////////////////////////////////////////////////////////////
16:
17: getid3_lib::IncludeDependency(GETID3_INCLUDEPATH.'module.audio.mp3.php', __FILE__, true);
18:
19: class getid3_mpeg extends getid3_handler {
20:
21: const START_CODE_BASE = "\x00\x00\x01";
22: const VIDEO_PICTURE_START = "\x00\x00\x01\x00";
23: const VIDEO_USER_DATA_START = "\x00\x00\x01\xB2";
24: const VIDEO_SEQUENCE_HEADER = "\x00\x00\x01\xB3";
25: const VIDEO_SEQUENCE_ERROR = "\x00\x00\x01\xB4";
26: const VIDEO_EXTENSION_START = "\x00\x00\x01\xB5";
27: const VIDEO_SEQUENCE_END = "\x00\x00\x01\xB7";
28: const VIDEO_GROUP_START = "\x00\x00\x01\xB8";
29: const AUDIO_START = "\x00\x00\x01\xC0";
30:
31:
32: public function Analyze() {
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'] ? ';' : ':'); //
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, $bitstreamoffset, 2); // 2 bits for marker_bits -- should be "10" = 2
353: echo 'marker_bits = '.$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'] *= $multiplier;
462: // //$info['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: $vbr_bitrates = array();
472: foreach ($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;
480: echo $gopkey.': ('.number_format($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[] = $this_bitrate;
484: }
485: }
486: }
487: echo 'average_File_bitrate = '.number_format(array_sum($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: }
504:
505: private function readBitsFromStream(&$bitstream, &$bitstreamoffset, $bits_to_read, $return_singlebit_as_boolean=true) {
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 $return;
512: }
513:
514:
515: public static function systemNonOverheadPercentage($VideoBitrate, $AudioBitrate) {
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 $OverheadPercentage;
564: }
565:
566:
567: public static function videoFramerateLookup($rawframerate) {
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: }
571:
572: public static function videoAspectRatioLookup($rawaspectratio) {
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: }
576:
577: public static function videoAspectRatioTextLookup($rawaspectratio) {
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: }
581:
582: public static function videoFormatTextLookup($video_format) {
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: }
587:
588: public static function scalableModeTextLookup($scalable_mode) {
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: }
593:
594: public static function pictureStructureTextLookup($picture_structure) {
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: }
599:
600: public static function chromaFormatTextLookup($chroma_format) {
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: }
605:
606: }