1@chapter Demuxers 2@c man begin DEMUXERS 3 4Demuxers are configured elements in FFmpeg that can read the 5multimedia streams from a particular type of file. 6 7When you configure your FFmpeg build, all the supported demuxers 8are enabled by default. You can list all available ones using the 9configure option @code{--list-demuxers}. 10 11You can disable all the demuxers using the configure option 12@code{--disable-demuxers}, and selectively enable a single demuxer with 13the option @code{--enable-demuxer=@var{DEMUXER}}, or disable it 14with the option @code{--disable-demuxer=@var{DEMUXER}}. 15 16The option @code{-formats} of the ff* tools will display the list of 17enabled demuxers. 18 19The description of some of the currently available demuxers follows. 20 21@section applehttp 22 23Apple HTTP Live Streaming demuxer. 24 25This demuxer presents all AVStreams from all variant streams. 26The id field is set to the bitrate variant index number. By setting 27the discard flags on AVStreams (by pressing 'a' or 'v' in ffplay), 28the caller can decide which variant streams to actually receive. 29The total bitrate of the variant that the stream belongs to is 30available in a metadata key named "variant_bitrate". 31 32@section asf 33 34Advanced Systems Format demuxer. 35 36This demuxer is used to demux ASF files and MMS network streams. 37 38@table @option 39@item -no_resync_search @var{bool} 40Do not try to resynchronize by looking for a certain optional start code. 41@end table 42 43@anchor{concat} 44@section concat 45 46Virtual concatenation script demuxer. 47 48This demuxer reads a list of files and other directives from a text file and 49demuxes them one after the other, as if all their packet had been muxed 50together. 51 52The timestamps in the files are adjusted so that the first file starts at 0 53and each next file starts where the previous one finishes. Note that it is 54done globally and may cause gaps if all streams do not have exactly the same 55length. 56 57All files must have the same streams (same codecs, same time base, etc.). 58 59The duration of each file is used to adjust the timestamps of the next file: 60if the duration is incorrect (because it was computed using the bit-rate or 61because the file is truncated, for example), it can cause artifacts. The 62@code{duration} directive can be used to override the duration stored in 63each file. 64 65@subsection Syntax 66 67The script is a text file in extended-ASCII, with one directive per line. 68Empty lines, leading spaces and lines starting with '#' are ignored. The 69following directive is recognized: 70 71@table @option 72 73@item @code{file @var{path}} 74Path to a file to read; special characters and spaces must be escaped with 75backslash or single quotes. 76 77All subsequent file-related directives apply to that file. 78 79@item @code{ffconcat version 1.0} 80Identify the script type and version. It also sets the @option{safe} option 81to 1 if it was to its default -1. 82 83To make FFmpeg recognize the format automatically, this directive must 84appears exactly as is (no extra space or byte-order-mark) on the very first 85line of the script. 86 87@item @code{duration @var{dur}} 88Duration of the file. This information can be specified from the file; 89specifying it here may be more efficient or help if the information from the 90file is not available or accurate. 91 92If the duration is set for all files, then it is possible to seek in the 93whole concatenated video. 94 95@item @code{stream} 96Introduce a stream in the virtual file. 97All subsequent stream-related directives apply to the last introduced 98stream. 99Some streams properties must be set in order to allow identifying the 100matching streams in the subfiles. 101If no streams are defined in the script, the streams from the first file are 102copied. 103 104@item @code{exact_stream_id @var{id}} 105Set the id of the stream. 106If this directive is given, the string with the corresponding id in the 107subfiles will be used. 108This is especially useful for MPEG-PS (VOB) files, where the order of the 109streams is not reliable. 110 111@end table 112 113@subsection Options 114 115This demuxer accepts the following option: 116 117@table @option 118 119@item safe 120If set to 1, reject unsafe file paths. A file path is considered safe if it 121does not contain a protocol specification and is relative and all components 122only contain characters from the portable character set (letters, digits, 123period, underscore and hyphen) and have no period at the beginning of a 124component. 125 126If set to 0, any file name is accepted. 127 128The default is -1, it is equivalent to 1 if the format was automatically 129probed and 0 otherwise. 130 131@item auto_convert 132If set to 1, try to perform automatic conversions on packet data to make the 133streams concatenable. 134 135Currently, the only conversion is adding the h264_mp4toannexb bitstream 136filter to H.264 streams in MP4 format. This is necessary in particular if 137there are resolution changes. 138 139@end table 140 141@section flv 142 143Adobe Flash Video Format demuxer. 144 145This demuxer is used to demux FLV files and RTMP network streams. 146 147@table @option 148@item -flv_metadata @var{bool} 149Allocate the streams according to the onMetaData array content. 150@end table 151 152@section libgme 153 154The Game Music Emu library is a collection of video game music file emulators. 155 156See @url{http://code.google.com/p/game-music-emu/} for more information. 157 158Some files have multiple tracks. The demuxer will pick the first track by 159default. The @option{track_index} option can be used to select a different 160track. Track indexes start at 0. The demuxer exports the number of tracks as 161@var{tracks} meta data entry. 162 163For very large files, the @option{max_size} option may have to be adjusted. 164 165@section libquvi 166 167Play media from Internet services using the quvi project. 168 169The demuxer accepts a @option{format} option to request a specific quality. It 170is by default set to @var{best}. 171 172See @url{http://quvi.sourceforge.net/} for more information. 173 174FFmpeg needs to be built with @code{--enable-libquvi} for this demuxer to be 175enabled. 176 177@section image2 178 179Image file demuxer. 180 181This demuxer reads from a list of image files specified by a pattern. 182The syntax and meaning of the pattern is specified by the 183option @var{pattern_type}. 184 185The pattern may contain a suffix which is used to automatically 186determine the format of the images contained in the files. 187 188The size, the pixel format, and the format of each image must be the 189same for all the files in the sequence. 190 191This demuxer accepts the following options: 192@table @option 193@item framerate 194Set the frame rate for the video stream. It defaults to 25. 195@item loop 196If set to 1, loop over the input. Default value is 0. 197@item pattern_type 198Select the pattern type used to interpret the provided filename. 199 200@var{pattern_type} accepts one of the following values. 201@table @option 202@item sequence 203Select a sequence pattern type, used to specify a sequence of files 204indexed by sequential numbers. 205 206A sequence pattern may contain the string "%d" or "%0@var{N}d", which 207specifies the position of the characters representing a sequential 208number in each filename matched by the pattern. If the form 209"%d0@var{N}d" is used, the string representing the number in each 210filename is 0-padded and @var{N} is the total number of 0-padded 211digits representing the number. The literal character '%' can be 212specified in the pattern with the string "%%". 213 214If the sequence pattern contains "%d" or "%0@var{N}d", the first filename of 215the file list specified by the pattern must contain a number 216inclusively contained between @var{start_number} and 217@var{start_number}+@var{start_number_range}-1, and all the following 218numbers must be sequential. 219 220For example the pattern "img-%03d.bmp" will match a sequence of 221filenames of the form @file{img-001.bmp}, @file{img-002.bmp}, ..., 222@file{img-010.bmp}, etc.; the pattern "i%%m%%g-%d.jpg" will match a 223sequence of filenames of the form @file{i%m%g-1.jpg}, 224@file{i%m%g-2.jpg}, ..., @file{i%m%g-10.jpg}, etc. 225 226Note that the pattern must not necessarily contain "%d" or 227"%0@var{N}d", for example to convert a single image file 228@file{img.jpeg} you can employ the command: 229@example 230ffmpeg -i img.jpeg img.png 231@end example 232 233@item glob 234Select a glob wildcard pattern type. 235 236The pattern is interpreted like a @code{glob()} pattern. This is only 237selectable if libavformat was compiled with globbing support. 238 239@item glob_sequence @emph{(deprecated, will be removed)} 240Select a mixed glob wildcard/sequence pattern. 241 242If your version of libavformat was compiled with globbing support, and 243the provided pattern contains at least one glob meta character among 244@code{%*?[]@{@}} that is preceded by an unescaped "%", the pattern is 245interpreted like a @code{glob()} pattern, otherwise it is interpreted 246like a sequence pattern. 247 248All glob special characters @code{%*?[]@{@}} must be prefixed 249with "%". To escape a literal "%" you shall use "%%". 250 251For example the pattern @code{foo-%*.jpeg} will match all the 252filenames prefixed by "foo-" and terminating with ".jpeg", and 253@code{foo-%?%?%?.jpeg} will match all the filenames prefixed with 254"foo-", followed by a sequence of three characters, and terminating 255with ".jpeg". 256 257This pattern type is deprecated in favor of @var{glob} and 258@var{sequence}. 259@end table 260 261Default value is @var{glob_sequence}. 262@item pixel_format 263Set the pixel format of the images to read. If not specified the pixel 264format is guessed from the first image file in the sequence. 265@item start_number 266Set the index of the file matched by the image file pattern to start 267to read from. Default value is 0. 268@item start_number_range 269Set the index interval range to check when looking for the first image 270file in the sequence, starting from @var{start_number}. Default value 271is 5. 272@item ts_from_file 273If set to 1, will set frame timestamp to modification time of image file. Note 274that monotonity of timestamps is not provided: images go in the same order as 275without this option. Default value is 0. 276If set to 2, will set frame timestamp to the modification time of the image file in 277nanosecond precision. 278@item video_size 279Set the video size of the images to read. If not specified the video 280size is guessed from the first image file in the sequence. 281@end table 282 283@subsection Examples 284 285@itemize 286@item 287Use @command{ffmpeg} for creating a video from the images in the file 288sequence @file{img-001.jpeg}, @file{img-002.jpeg}, ..., assuming an 289input frame rate of 10 frames per second: 290@example 291ffmpeg -framerate 10 -i 'img-%03d.jpeg' out.mkv 292@end example 293 294@item 295As above, but start by reading from a file with index 100 in the sequence: 296@example 297ffmpeg -framerate 10 -start_number 100 -i 'img-%03d.jpeg' out.mkv 298@end example 299 300@item 301Read images matching the "*.png" glob pattern , that is all the files 302terminating with the ".png" suffix: 303@example 304ffmpeg -framerate 10 -pattern_type glob -i "*.png" out.mkv 305@end example 306@end itemize 307 308@section mpegts 309 310MPEG-2 transport stream demuxer. 311 312@table @option 313 314@item fix_teletext_pts 315Overrides teletext packet PTS and DTS values with the timestamps calculated 316from the PCR of the first program which the teletext stream is part of and is 317not discarded. Default value is 1, set this option to 0 if you want your 318teletext packet PTS and DTS values untouched. 319@end table 320 321@section rawvideo 322 323Raw video demuxer. 324 325This demuxer allows one to read raw video data. Since there is no header 326specifying the assumed video parameters, the user must specify them 327in order to be able to decode the data correctly. 328 329This demuxer accepts the following options: 330@table @option 331 332@item framerate 333Set input video frame rate. Default value is 25. 334 335@item pixel_format 336Set the input video pixel format. Default value is @code{yuv420p}. 337 338@item video_size 339Set the input video size. This value must be specified explicitly. 340@end table 341 342For example to read a rawvideo file @file{input.raw} with 343@command{ffplay}, assuming a pixel format of @code{rgb24}, a video 344size of @code{320x240}, and a frame rate of 10 images per second, use 345the command: 346@example 347ffplay -f rawvideo -pixel_format rgb24 -video_size 320x240 -framerate 10 input.raw 348@end example 349 350@section sbg 351 352SBaGen script demuxer. 353 354This demuxer reads the script language used by SBaGen 355@url{http://uazu.net/sbagen/} to generate binaural beats sessions. A SBG 356script looks like that: 357@example 358-SE 359a: 300-2.5/3 440+4.5/0 360b: 300-2.5/0 440+4.5/3 361off: - 362NOW == a 363+0:07:00 == b 364+0:14:00 == a 365+0:21:00 == b 366+0:30:00 off 367@end example 368 369A SBG script can mix absolute and relative timestamps. If the script uses 370either only absolute timestamps (including the script start time) or only 371relative ones, then its layout is fixed, and the conversion is 372straightforward. On the other hand, if the script mixes both kind of 373timestamps, then the @var{NOW} reference for relative timestamps will be 374taken from the current time of day at the time the script is read, and the 375script layout will be frozen according to that reference. That means that if 376the script is directly played, the actual times will match the absolute 377timestamps up to the sound controller's clock accuracy, but if the user 378somehow pauses the playback or seeks, all times will be shifted accordingly. 379 380@section tedcaptions 381 382JSON captions used for @url{http://www.ted.com/, TED Talks}. 383 384TED does not provide links to the captions, but they can be guessed from the 385page. The file @file{tools/bookmarklets.html} from the FFmpeg source tree 386contains a bookmarklet to expose them. 387 388This demuxer accepts the following option: 389@table @option 390@item start_time 391Set the start time of the TED talk, in milliseconds. The default is 15000 392(15s). It is used to sync the captions with the downloadable videos, because 393they include a 15s intro. 394@end table 395 396Example: convert the captions to a format most players understand: 397@example 398ffmpeg -i http://www.ted.com/talks/subtitles/id/1/lang/en talk1-en.srt 399@end example 400 401@c man end DEMUXERS 402