泛站蜘蛛池 站群蜘蛛池

边缘计算中的实时问答_边缘计算实时问答系统：关键技术与应用解析

　　ffprobe [options] input_url 　　ffprobe gathers information from multimedia streams and prints it in 　　human- and machine-readable fashion. 　　For example it can be used to check the format of the container used 　　by a multimedia stream and the format and type of each media stream 　　contained in it. 　　If a url is specified in input, ffprobe will try to open and 　　probe the url content. If the url cannot be opened or recognized as 　　a multimedia file, a positive exit code is returned. 　　If no output is specified as output with o ffprobe will write 　　to stdout. 　　ffprobe may be employed both as a standalone application or in 　　combination with a textual filter, which may perform more 　　sophisticated processing, e.g. statistical processing or plotting. 　　Options are used to list some of the formats supported by ffprobe or 　　for specifying which information to display, and for setting how 　　ffprobe will show it. 　　ffprobe output is designed to be easily parsable by a textual filter, 　　and consists of one or more sections of a form defined by the selected 　　writer, which is specified by the output_format option. 　　Sections may contain other nested sections, and are identified by a 　　name (which may be shared by other sections), and an unique 　　name. See the output of sections. 　　Metadata tags stored in the container or in the streams are recognized 　　and printed in the corresponding "FORMAT", "STREAM", "STREAM_GROUP_STREAM" 　　or "PROGRAM_STREAM" section. 　　All the numerical options, if not specified otherwise, accept a string 　　representing a number as input, which may be followed by one of the SI 　　unit prefixes, for example: ’K’, ’M’, or ’G’. 　　If ’i’ is appended to the SI unit prefix, the complete prefix will be 　　interpreted as a unit prefix for binary multiples, which are based on 　　powers of 1024 instead of powers of 1000. Appending ’B’ to the SI unit 　　prefix multiplies the value by 8. This allows using, for example: 　　’KB’, ’MiB’, ’G’ and ’B’ as number suffixes. 　　Options which do not take arguments are boolean options, and set the 　　corresponding value to true. They can be set to false by prefixing 　　the option name with "no". For example using "-nofoo" 　　will set the boolean option with name "foo" to false. 　　Options that take arguments support a special syntax where the argument given on 　　the command line is interpreted as a path to the file from which the actual 　　argument value is loaded. To use this feature, add a forward slash ’/’ 　　immediately before the option name (after the leading dash). E.g. 　　ffmpeg -i INPUT -/filter:v filter.script OUTPUT 　　will load a filtergraph description from the file named filter.script. 　　Some options are applied per-stream, e.g. bitrate or codec. Stream specifiers 　　are used to precisely specify which stream(s) a given option belongs to. 　　A stream specifier is a string generally appended to the option name and 　　separated from it by a colon. E.g. contains the 　　stream specifier, which matches the second audio stream. Therefore, it 　　would select the ac3 codec for the second audio stream. 　　A stream specifier can match several streams, so that the option is applied to all 　　of them. E.g. the stream specifier in matches all audio 　　streams. 　　An empty stream specifier matches all streams. For example, 　　or would copy all the streams without reencoding. 　　Possible forms of stream specifiers are: 　　stream_index 　　Matches the stream with this index. E.g. would set the 　　thread count for the second stream to 4. If stream_index is used as an 　　additional stream specifier (see below), then it selects stream number 　　stream_index from the matching streams. Stream numbering is based on the 　　order of the streams as detected by libavformat except when a stream group 　　specifier or program ID is also specified. In this case it is based on the 　　ordering of the streams in the group or program. 　　stream_type[:additional_stream_specifier] 　　stream_type is one of following: ’v’ or ’V’ for video, ’a’ for audio, ’s’ 　　for subtitle, ’d’ for data, and ’t’ for attachments. ’v’ matches all video 　　streams, ’V’ only matches video streams which are not attached pictures, video 　　thumbnails or cover arts. If additional_stream_specifier is used, then 　　it matches streams which both have this type and match the 　　additional_stream_specifier. Otherwise, it matches all streams of the 　　specified type. 　　g:group_specifier[:additional_stream_specifier] 　　Matches streams which are in the group with the specifier group_specifier. 　　if additional_stream_specifier is used, then it matches streams which both 　　are part of the group and match the additional_stream_specifier. 　　group_specifier may be one of the following: 　　group_index 　　Match the stream with this group index. 　　#group_id or i:group_id 　　Match the stream with this group id. 　　p:program_id[:additional_stream_specifier] 　　Matches streams which are in the program with the id program_id. If 　　additional_stream_specifier is used, then it matches streams which both 　　are part of the program and match the additional_stream_specifier. 　　#stream_id or i:stream_id 　　Match the stream by stream id (e.g. PID in MPEG-TS container). 　　m:key[:value] 　　Matches streams with the metadata tag key having the specified value. If 　　value is not given, matches streams that contain the given tag with any 　　value. The colon character ’:’ in key or value needs to be 　　backslash-escaped. 　　disp:dispositions[:additional_stream_specifier] 　　Matches streams with the given disposition(s). dispositions is a list of 　　one or more dispositions (as printed by the -dispositions option) 　　joined with ’+’. 　　u 　　Matches streams with usable configuration, the codec must be defined and the 　　essential information such as video dimension or audio sample rate must be present. 　　Note that in , matching by metadata will only work properly for 　　input files. 　　These options are shared amongst the ff* tools. 　　-L, -license 　　Show license. 　　-h, -?, -help, --help [arg] 　　Show help. An optional parameter may be specified to print help about a specific 　　item. If no argument is specified, only basic (non advanced) tool 　　options are shown. 　　Possible values of arg are: 　　long 　　Print advanced tool options in addition to the basic tool options. 　　full 　　Print complete list of options, including shared and private options 　　for encoders, decoders, demuxers, muxers, filters, etc. 　　decoder=decoder_name 　　Print detailed information about the decoder named decoder_name. Use the 　　-decoders option to get a list of all decoders. 　　encoder=encoder_name 　　Print detailed information about the encoder named encoder_name. Use the 　　-encoders option to get a list of all encoders. 　　demuxer=demuxer_name 　　Print detailed information about the demuxer named demuxer_name. Use the 　　-formats option to get a list of all demuxers and muxers. 　　muxer=muxer_name 　　Print detailed information about the muxer named muxer_name. Use the 　　-formats option to get a list of all muxers and demuxers. 　　filter=filter_name 　　Print detailed information about the filter named filter_name. Use the 　　-filters option to get a list of all filters. 　　bsf=bitstream_filter_name 　　Print detailed information about the bitstream filter named bitstream_filter_name. 　　Use the -bsfs option to get a list of all bitstream filters. 　　protocol=protocol_name 　　Print detailed information about the protocol named protocol_name. 　　Use the -protocols option to get a list of all protocols. 　　-version 　　Show version. 　　-buildconf 　　Show the build configuration, one option per line. 　　-formats 　　Show available formats (including devices). 　　-demuxers 　　Show available demuxers. 　　-muxers 　　Show available muxers. 　　-devices 　　Show available devices. 　　-codecs 　　Show all codecs known to libavcodec. 　　Note that the term ’codec’ is used throughout this documentation as a shortcut 　　for what is more correctly called a media bitstream format. 　　-decoders 　　Show available decoders. 　　-encoders 　　Show all available encoders. 　　-bsfs 　　Show available bitstream filters. 　　-protocols 　　Show available protocols. 　　-filters 　　Show available libavfilter filters. 　　-pix_fmts 　　Show available pixel formats. 　　-sample_fmts 　　Show available sample formats. 　　-layouts 　　Show channel names and standard channel layouts. 　　-dispositions 　　Show stream dispositions. 　　-colors 　　Show recognized color names. 　　-sources device[,opt1=val1[,opt2=val2]...] 　　Show autodetected sources of the input device. 　　Some devices may provide system-dependent source names that cannot be autodetected. 　　The returned list cannot be assumed to be always complete. 　　ffmpeg -sources pulse,server=192.168.0.4 　　-sinks device[,opt1=val1[,opt2=val2]...] 　　Show autodetected sinks of the output device. 　　Some devices may provide system-dependent sink names that cannot be autodetected. 　　The returned list cannot be assumed to be always complete. 　　ffmpeg -sinks pulse,server=192.168.0.4 　　-loglevel [flags+]loglevel | -v [flags+]loglevel 　　Set logging level and flags used by the library. 　　The optional flags prefix can consist of the following values: 　　‘repeat’ 　　Indicates that repeated log output should not be compressed to the first line 　　and the "Last message repeated n times" line will be omitted. 　　‘level’ 　　Indicates that log output should add a prefix to each message 　　line. This can be used as an alternative to log coloring, e.g. when dumping the 　　log to file. 　　‘time’ 　　Indicates that log lines should be prefixed with time information. 　　‘datetime’ 　　Indicates that log lines should be prefixed with date and time information. 　　Flags can also be used alone by adding a ’+’/’-’ prefix to set/reset a single 　　flag without affecting other flags or changing loglevel. When 　　setting both flags and loglevel, a ’+’ separator is expected 　　between the last flags value and before loglevel. 　　loglevel is a string or a number containing one of the following values: 　　‘quiet, -8’ 　　Show nothing at all; be silent. 　　‘panic, 0’ 　　Only show fatal errors which could lead the process to crash, such as 　　an assertion failure. This is not currently used for anything. 　　‘fatal, 8’ 　　Only show fatal errors. These are errors after which the process absolutely 　　cannot continue. 　　‘error, 16’ 　　Show all errors, including ones which can be recovered from. 　　‘warning, 24’ 　　Show all warnings and errors. Any message related to possibly 　　incorrect or unexpected events will be shown. 　　‘info, 32’ 　　Show informative messages during processing. This is in addition to 　　warnings and errors. This is the default value. 　　‘verbose, 40’ 　　Same as , except more verbose. 　　‘debug, 48’ 　　Show everything, including debugging information. 　　‘trace, 56’ 　　For example to enable repeated log output, add the prefix, and set 　　loglevel to : 　　ffmpeg -loglevel repeat+level+verbose -i input output 　　Another example that enables repeated log output without affecting current 　　state of prefix flag or loglevel: 　　ffmpeg [...] -loglevel +repeat 　　By default the program logs to stderr. If coloring is supported by the 　　terminal, colors are used to mark errors and warnings. Log coloring 　　can be disabled setting the environment variable 　　, or can be forced setting 　　the environment variable . 　　-report 　　Dump full command line and log output to a file named 　　in the current 　　directory. 　　This file can be useful for bug reports. 　　It also implies . 　　Setting the environment variable to any value has the 　　same effect. If the value is a ’:’-separated key=value sequence, these 　　options will affect the report; option values must be escaped if they 　　contain special characters or the options delimiter ’:’ (see the 　　“Quoting and escaping” section in the ffmpeg-utils manual). 　　The following options are recognized: 　　file 　　set the file name to use for the report; is expanded to the name 　　of the program, is expanded to a timestamp, is expanded 　　to a plain 　　level 　　set the log verbosity level using a numerical value (see ). 　　For example, to output a report to a file named ffreport.log 　　using a log level of (alias for log level ): 　　FFREPORT=file=ffreport.log:level=32 ffmpeg -i input output 　　Errors in parsing the environment variable are not fatal, and will not 　　appear in the report. 　　-hide_banner 　　Suppress printing banner. 　　All FFmpeg tools will normally show a copyright notice, build options 　　and library versions. This option can be used to suppress printing 　　this information. 　　-cpuflags flags (global) 　　Allows setting and clearing cpu flags. This option is intended 　　for testing. Do not use it unless you know what you’re doing. 　　ffmpeg -cpuflags -sse+mmx ... 　　ffmpeg -cpuflags mmx ... 　　ffmpeg -cpuflags 0 ... 　　Possible flags for this option are: 　　‘x86’ 　　‘mmx’ 　　‘mmxext’ 　　‘sse’ 　　‘sse2’ 　　‘sse2slow’ 　　‘sse3’ 　　‘sse3slow’ 　　‘ssse3’ 　　‘atom’ 　　‘sse4.1’ 　　‘sse4.2’ 　　‘avx’ 　　‘avx2’ 　　‘xop’ 　　‘fma3’ 　　‘fma4’ 　　‘3dnow’ 　　‘3dnowext’ 　　‘bmi1’ 　　‘bmi2’ 　　‘cmov’ 　　‘ARM’ 　　‘armv5te’ 　　‘armv6’ 　　‘armv6t2’ 　　‘vfp’ 　　‘vfpv3’ 　　‘neon’ 　　‘setend’ 　　‘AArch64’ 　　‘armv8’ 　　‘vfp’ 　　‘neon’ 　　‘PowerPC’ 　　‘altivec’ 　　‘Specific Processors’ 　　‘pentium2’ 　　‘pentium3’ 　　‘pentium4’ 　　‘k6’ 　　‘k62’ 　　‘athlon’ 　　‘athlonxp’ 　　‘k8’ 　　-cpucount count (global) 　　Override detection of CPU count. This option is intended 　　for testing. Do not use it unless you know what you’re doing. 　　ffmpeg -cpucount 2 　　-max_alloc bytes 　　Set the maximum size limit for allocating a block on the heap by ffmpeg’s 　　family of malloc functions. Exercise extreme caution when using 　　this option. Don’t use if you do not understand the full consequence of doing so. 　　Default is INT_MAX. 　　These options are provided directly by the libavformat, libavdevice and 　　libavcodec libraries. To see the list of available AVOptions, use the 　　-help option. They are separated into two categories: 　　generic 　　These options can be set for any container, codec or device. Generic options 　　are listed under AVFormatContext options for containers/devices and under 　　AVCodecContext options for codecs. 　　private 　　These options are specific to the given container, device or codec. Private 　　options are listed under their corresponding containers/devices/codecs. 　　For example to write an ID3v2.3 header instead of a default ID3v2.4 to 　　an MP3 file, use the id3v2_version private option of the MP3 　　muxer: 　　ffmpeg -i input.flac -id3v2_version 3 out.mp3 　　All codec AVOptions are per-stream, and thus a stream specifier 　　should be attached to them: 　　ffmpeg -i multichannel.mxf -map 0:v:0 -map 0:a:0 -map 0:a:0 -c:a:0 ac3 -b:a:0 640k -ac:a:1 2 -c:a:1 aac -b:2 128k out.mp4 　　In the above example, a multichannel audio stream is mapped twice for output. 　　The first instance is encoded with codec ac3 and bitrate 640k. 　　The second instance is downmixed to 2 channels and encoded with codec aac. A bitrate of 128k is specified for it using 　　absolute index of the output stream. 　　Note: the -nooption syntax cannot be used for boolean 　　AVOptions, use -option 0/-option 1. 　　Note: the old undocumented way of specifying per-stream AVOptions by 　　prepending v/a/s to the options name is now obsolete and will be 　　removed soon. 　　-f format 　　Force format to use. 　　-unit 　　Show the unit of the displayed values. 　　-prefix 　　Use SI prefixes for the displayed values. 　　Unless the "-byte_binary_prefix" option is used all the prefixes 　　are decimal. 　　-byte_binary_prefix 　　Force the use of binary prefixes for byte values. 　　-sexagesimal 　　Use sexagesimal format HH:MM:SS.MICROSECONDS for time values. 　　-pretty 　　Prettify the format of the displayed values, it corresponds to the 　　options "-unit -prefix -byte_binary_prefix -sexagesimal". 　　-output_format, -of, -print_format writer_name[=writer_options] 　　Set the output printing format. 　　writer_name specifies the name of the writer, and 　　writer_options specifies the options to be passed to the writer. 　　For example for printing the output in JSON format, specify: 　　-output_format json 　　For more details on the available output printing formats, see the 　　Writers section below. 　　-sections 　　Print sections structure and section information, and exit. The output 　　is not meant to be parsed by a machine. 　　-select_streams stream_specifier 　　Select only the streams specified by stream_specifier. This 　　option affects only the options related to streams 　　(e.g. , , etc.). 　　For example to show only audio streams, you can use the command: 　　ffprobe -show_streams -select_streams a INPUT 　　To show only video packets belonging to the video stream with index 1: 　　ffprobe -show_packets -select_streams v:1 INPUT 　　-show_data 　　Show payload data, as a hexadecimal and ASCII dump (other formats can be 　　selected using -data_dump_format). Coupled with 　　-show_packets, it will dump the packets’ data. Coupled with 　　-show_streams, it will dump the codec extradata. 　　The dump is printed as the "data" field. It may contain newlines. 　　-show_data_hash algorithm 　　Show a hash of payload data, for packets with -show_packets and for 　　codec extradata with -show_streams. 　　-data_dump_format format 　　Select a format used for the data dumps enabled with the -show_data 　　option. The default is which is a hexdump format compatible with the 　　well-known program. is also supported. 　　-show_error 　　Show information about the error found when trying to probe the input. 　　The error information is printed within a section with name "ERROR". 　　-show_format 　　Show information about the container format of the input multimedia 　　stream. 　　All the container format information is printed within a section with 　　name "FORMAT". 　　-show_entries section_entries 　　Set list of entries to show. 　　Entries are specified according to the following 　　syntax. section_entries contains a list of section entries 　　separated by . Each section entry is composed by a section 　　name (or unique name), optionally followed by a list of entries local 　　to that section, separated by . 　　If section name is specified but is followed by no , all 　　entries are printed to output, together with all the contained 　　sections. Otherwise only the entries specified in the local section 　　entries list are printed. In particular, if is specified but 　　the list of local entries is empty, then no entries will be shown for 　　that section. 　　Note that the order of specification of the local section entries is 　　not honored in the output, and the usual display order will be 　　retained. 　　The formal syntax is given by: 　　LOCAL_SECTION_ENTRIES ::= SECTION_ENTRY_NAME[,LOCAL_SECTION_ENTRIES] 　　SECTION_ENTRY ::= SECTION_NAME[=[LOCAL_SECTION_ENTRIES]] 　　SECTION_ENTRIES ::= SECTION_ENTRY[:SECTION_ENTRIES] 　　For example, to show only the index and type of each stream, and the PTS 　　time, duration time, and stream index of the packets, you can specify 　　the argument: 　　packet=pts_time,duration_time,stream_index : stream=index,codec_type 　　To show all the entries in the section "format", but only the codec 　　type in the section "stream", specify the argument: 　　format : stream=codec_type 　　To show all the tags in the stream and format sections: 　　stream_tags : format_tags 　　To show only the tag (if available) in the stream 　　sections: 　　stream_tags=title 　　-show_packets 　　Show information about each packet contained in the input multimedia 　　stream. 　　The information for each single packet is printed within a dedicated 　　section with name "PACKET". 　　-show_frames 　　Show information about each frame and subtitle contained in the input 　　multimedia stream. 　　The information for each single frame is printed within a dedicated 　　section with name "FRAME" or "SUBTITLE". 　　-show_log loglevel 　　Show logging information from the decoder about each frame according to 　　the value set in loglevel, (see ). This option requires . 　　The information for each log message is printed within a dedicated 　　section with name "LOG". 　　-show_streams 　　Show information about each media stream contained in the input 　　multimedia stream. 　　Each media stream information is printed within a dedicated section 　　with name "STREAM". 　　-show_programs 　　Show information about programs and their streams contained in the input 　　multimedia stream. 　　Each media stream information is printed within a dedicated section 　　with name "PROGRAM_STREAM". 　　-show_stream_groups 　　Show information about stream groups and their streams contained in the 　　input multimedia stream. 　　Each media stream information is printed within a dedicated section 　　with name "STREAM_GROUP_STREAM". 　　-show_chapters 　　Show information about chapters stored in the format. 　　Each chapter is printed within a dedicated section with name "CHAPTER". 　　-count_frames 　　Count the number of frames per stream and report it in the 　　corresponding stream section. 　　-count_packets 　　Count the number of packets per stream and report it in the 　　corresponding stream section. 　　-read_intervals read_intervals 　　Read only the specified intervals. read_intervals must be a 　　sequence of interval specifications separated by ",". 　　will seek to the interval starting point, and will 　　continue reading from that. 　　Each interval is specified by two optional parts, separated by "%". 　　The first part specifies the interval start position. It is 　　interpreted as an absolute position, or as a relative offset from the 　　current position if it is preceded by the "+" character. If this first 　　part is not specified, no seeking will be performed when reading this 　　interval. 　　The second part specifies the interval end position. It is interpreted 　　as an absolute position, or as a relative offset from the current 　　position if it is preceded by the "+" character. If the offset 　　specification starts with "#", it is interpreted as the number of 　　packets to read (not including the flushing packets) from the interval 　　start. If no second part is specified, the program will read until the 　　end of the input. 　　Note that seeking is not accurate, thus the actual interval start 　　point may be different from the specified position. Also, when an 　　interval duration is specified, the absolute end time will be computed 　　by adding the duration to the interval start point found by seeking 　　the file, rather than to the specified start value. 　　The formal syntax is given by: 　　INTERVAL ::= [START|+START_OFFSET][%[END|+END_OFFSET]] 　　INTERVALS ::= INTERVAL[,INTERVALS] 　　A few examples follow. 　　Seek to time 10, read packets until 20 seconds after the found seek 　　point, then seek to position (1 minute and thirty 　　seconds) and read packets until position . 　　10%+20,01:30%01:45 　　Read only 42 packets after seeking to position : 　　01:23%+#42 　　Read only the first 20 seconds from the start: 　　%+20 　　Read from the start until position : 　　%02:30 　　-show_private_data, -private 　　Show private data, that is data depending on the format of the 　　particular shown element. 　　This option is enabled by default, but you may need to disable it 　　for specific uses, for example when creating XSD-compliant XML output. 　　-show_program_version 　　Show information related to program version. 　　Version information is printed within a section with name 　　"PROGRAM_VERSION". 　　-show_library_versions 　　Show information related to library versions. 　　Version information for each library is printed within a section with 　　name "LIBRARY_VERSION". 　　-show_versions 　　Show information related to program and library versions. This is the 　　equivalent of setting both -show_program_version and 　　-show_library_versions options. 　　-show_pixel_formats 　　Show information about all pixel formats supported by FFmpeg. 　　Pixel format information for each format is printed within a section 　　with name "PIXEL_FORMAT". 　　-show_optional_fields value 　　Some writers viz. JSON and XML, omit the printing of fields with invalid or non-applicable values, 　　while other writers always print them. This option enables one to control this behaviour. 　　Valid values are /, / and /. 　　Default is auto. 　　-analyze_frames 　　Analyze frames and/or their side data up to the provided read interval, 　　providing additional information that may be useful at a stream level. 　　Must be paired with the -show_streams option or it will have no effect. 　　Currently, the additional fields provided by this option when enabled are the 　　and fields. 　　For example, to analyze the first 20 seconds and populate these fields: 　　ffprobe -show_streams -analyze_frames -read_intervals "%+20" INPUT 　　-bitexact 　　Force bitexact output, useful to produce output which is not dependent 　　on the specific build. 　　-i input_url 　　Read input_url. 　　-o output_url 　　Write output to output_url. If not specified, the output is sent 　　to stdout. 　　-c:media_specifier codec_name 　　-codec:media_specifier codec_name 　　Force a specific decoder implementation for the stream identified by 　　media_specifier, which can assume the values (audio), 　　(video), (subtitle), and (data). 　　A writer defines the output format adopted by , and will be 　　used for printing all the parts of the output. 　　A writer may accept one or more arguments, which specify the options 　　to adopt. The options are specified as a list of key=value 　　pairs, separated by ":". 　　All writers support the following options: 　　string_validation, sv 　　Set string validation mode. 　　The following values are accepted. 　　‘fail’ 　　The writer will fail immediately in case an invalid string (UTF-8) 　　sequence or code point is found in the input. This is especially 　　useful to validate input metadata. 　　‘ignore’ 　　Any validation error will be ignored. This will result in possibly 　　broken output, especially with the json or xml writer. 　　‘replace’ 　　The writer will substitute invalid UTF-8 sequences or code points with 　　the string specified with the string_validation_replacement. 　　Default value is ‘replace’. 　　string_validation_replacement, svr 　　Set replacement string to use in case string_validation is 　　set to ‘replace’. 　　In case the option is not specified, the writer will assume the empty 　　string, that is it will remove the invalid sequences from the input 　　strings. 　　A description of the currently available writers follows. 　　Default format. 　　Print each section in the form: 　　[SECTION] 　　key1=val1 　　... 　　keyN=valN 　　[/SECTION] 　　Metadata tags are printed as a line in the corresponding FORMAT, STREAM, 　　STREAM_GROUP_STREAM or PROGRAM_STREAM section, and are prefixed by the 　　string "TAG:". 　　A description of the accepted options follows. 　　nokey, nk 　　If set to 1 specify not to print the key of each field. Default value 　　is 0. 　　noprint_wrappers, nw 　　If set to 1 specify not to print the section header and footer. 　　Default value is 0. 　　Compact and CSV format. 　　The writer is equivalent to , but supports 　　different defaults. 　　Each section is printed on a single line. 　　If no option is specified, the output has the form: 　　section|key1=val1| ... |keyN=valN 　　Metadata tags are printed in the corresponding "format" or "stream" 　　section. A metadata tag key, if printed, is prefixed by the string 　　"tag:". 　　The description of the accepted options follows. 　　item_sep, s 　　Specify the character to use for separating fields in the output line. 　　It must be a single printable character, it is "|" by default ("," for 　　the writer). 　　nokey, nk 　　If set to 1 specify not to print the key of each field. Its default 　　value is 0 (1 for the writer). 　　escape, e 　　Set the escape mode to use, default to "c" ("csv" for the 　　writer). 　　It can assume one of the following values: 　　c 　　Perform C-like escaping. Strings containing a newline (‘ 　　’), carriage 　　return (‘ 　　’), a tab (‘ ’), a form feed (‘f’), the escaping 　　character (‘’) or the item separator character SEP are escaped 　　using C-like fashioned escaping, so that a newline is converted to the 　　sequence ‘ 　　’, a carriage return to ‘ 　　’, ‘’ to ‘\’ and 　　the separator SEP is converted to ‘SEP’. 　　csv 　　Perform CSV-like escaping, as described in RFC4180. Strings 　　containing a newline (‘ 　　’), a carriage return (‘ 　　’), a double quote 　　(‘"’), or SEP are enclosed in double-quotes. 　　none 　　Perform no escaping. 　　print_section, p 　　Print the section name at the beginning of each line if the value is 　　, disable it with value set to . Default value is 　　. 　　Flat format. 　　A free-form output where each line contains an explicit key=value, such as 　　"streams.stream.3.tags.foo=bar". The output is shell escaped, so it can be 　　directly embedded in sh scripts as long as the separator character is an 　　alphanumeric character or an underscore (see sep_char option). 　　The description of the accepted options follows. 　　sep_char, s 　　Separator character used to separate the chapter, the section name, IDs and 　　potential tags in the printed field key. 　　Default value is ‘.’. 　　hierarchical, h 　　Specify if the section name specification should be hierarchical. If 　　set to 1, and if there is more than one section in the current 　　chapter, the section name will be prefixed by the name of the 　　chapter. A value of 0 will disable this behavior. 　　Default value is 1. 　　INI format output. 　　Print output in an INI based format. 　　The following conventions are adopted: 　　all key and values are UTF-8 　　‘.’ is the subgroup separator 　　newline, ‘ ’, ‘f’, ‘b’ and the following characters are 　　escaped 　　‘’ is the escape character 　　‘#’ is the comment indicator 　　‘=’ is the key/value separator 　　‘:’ is not used but usually parsed as key/value separator 　　This writer accepts options as a list of key=value pairs, 　　separated by ‘:’. 　　The description of the accepted options follows. 　　hierarchical, h 　　Specify if the section name specification should be hierarchical. If 　　set to 1, and if there is more than one section in the current 　　chapter, the section name will be prefixed by the name of the 　　chapter. A value of 0 will disable this behavior. 　　Default value is 1. 　　JSON based format. 　　Each section is printed using JSON notation. 　　The description of the accepted options follows. 　　compact, c 　　If set to 1 enable compact output, that is each section will be 　　printed on a single line. Default value is 0. 　　For more information about JSON, see http://www.json.org/. 　　XML based format. 　　The XML output is described in the XML schema description file 　　ffprobe.xsd installed in the FFmpeg datadir. 　　An updated version of the schema can be retrieved at the url 　　http://www.ffmpeg.org/schema/ffprobe.xsd, which redirects to the 　　latest schema committed into the FFmpeg development source code tree. 　　Note that the output issued will be compliant to the 　　ffprobe.xsd schema only when no special global output options 　　(unit, prefix, byte_binary_prefix, 　　sexagesimal etc.) are specified. 　　The description of the accepted options follows. 　　fully_qualified, q 　　If set to 1 specify if the output should be fully qualified. Default 　　value is 0. 　　This is required for generating an XML file which can be validated 　　through an XSD file. 　　xsd_strict, x 　　If set to 1 perform more checks for ensuring that the output is XSD 　　compliant. Default value is 0. 　　This option automatically sets fully_qualified to 1. 　　For more information about the XML format, see 　　https://www.w3.org/XML/. 　　supports Timecode extraction: 　　MPEG1/2 timecode is extracted from the GOP, and is available in the video 　　stream details (-show_streams, see timecode). 　　MOV timecode is extracted from tmcd track, so is available in the tmcd 　　stream metadata (-show_streams, see TAG:timecode). 　　DV, GXF and AVI timecodes are available in format metadata 　　(-show_format, see TAG:timecode). 　　ffprobe-all, 　　ffmpeg, ffplay, 　　ffmpeg-utils, 　　ffmpeg-scaler, 　　ffmpeg-resampler, 　　ffmpeg-codecs, 　　ffmpeg-bitstream-filters, 　　ffmpeg-formats, 　　ffmpeg-devices, 　　ffmpeg-protocols, 　　ffmpeg-filters 　　The FFmpeg developers. 　　For details about the authorship, see the Git history of the project 　　(https://git.ffmpeg.org/ffmpeg), e.g. by typing the command 　　in the FFmpeg source directory, or browsing the 　　online repository at https://git.ffmpeg.org/ffmpeg. 　　Maintainers for the specific components are listed in the file 　　MAINTAINERS in the source code tree. 　　This document was generated on March 17, 2026 using makeinfo. 　　Hosting provided by telepoint.bg

51直播nba免费观看应用