@table @option
@item @var{stream_index}
Matches the stream with this index. E.g. @code{-threads:1 4} would set the
-thread count for the second stream to 4.
-@item @var{stream_type}[:@var{stream_index}]
+thread count for the second stream to 4. If @var{stream_index} is used as an
+additional stream specifier (see below), then it selects stream number
+@var{stream_index} from the matching streams.
+@item @var{stream_type}[:@var{additional_stream_specifier}]
@var{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 @var{stream_index} is given, then it matches
-stream number @var{stream_index} of this type. Otherwise, it matches all
-streams of this type.
-@item p:@var{program_id}[:@var{stream_index}]
-If @var{stream_index} is given, then it matches the stream with number @var{stream_index}
-in the program with the id @var{program_id}. Otherwise, it matches all streams in the
-program.
+thumbnails or cover arts. If @var{additional_stream_specifier} is used, then
+it matches streams which both have this type and match the
+@var{additional_stream_specifier}. Otherwise, it matches all streams of the
+specified type.
+@item p:@var{program_id}[:@var{additional_stream_specifier}]
+Matches streams which are in the program with the id @var{program_id}. If
+@var{additional_stream_specifier} is used, then it matches streams which both
+are part of the program and match the @var{additional_stream_specifier}.
+
@item #@var{stream_id} or i:@var{stream_id}
Match the stream by stream id (e.g. PID in MPEG-TS container).
@item m:@var{key}[:@var{value}]
ffmpeg -sinks pulse,server=192.168.0.4
@end example
-@item -loglevel [repeat+]@var{loglevel} | -v [repeat+]@var{loglevel}
-Set the logging level used by the library.
-Adding "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. "repeat" can also be used alone.
-If "repeat" is used alone, and with no prior loglevel set, the default
-loglevel will be used. If multiple loglevel parameters are given, using
-'repeat' will not change the loglevel.
+@item -loglevel [@var{flags}+]@var{loglevel} | -v [@var{flags}+]@var{loglevel}
+Set logging level and flags used by the library.
+
+The optional @var{flags} prefix can consist of the following values:
+@table @samp
+@item 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.
+@item level
+Indicates that log output should add a @code{[level]} prefix to each message
+line. This can be used as an alternative to log coloring, e.g. when dumping the
+log to file.
+@end table
+Flags can also be used alone by adding a '+'/'-' prefix to set/reset a single
+flag without affecting other @var{flags} or changing @var{loglevel}. When
+setting both @var{flags} and @var{loglevel}, a '+' separator is expected
+between the last @var{flags} value and before @var{loglevel}.
+
@var{loglevel} is a string or a number containing one of the following values:
@table @samp
@item quiet, -8
@item trace, 56
@end table
+For example to enable repeated log output, add the @code{level} prefix, and set
+@var{loglevel} to @code{verbose}:
+@example
+ffmpeg -loglevel repeat+level+verbose -i input output
+@end example
+Another example that enables repeated log output without affecting current
+state of @code{level} prefix flag or @var{loglevel}:
+@example
+ffmpeg [...] -loglevel +repeat
+@end example
+
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
@code{@var{program}-@var{YYYYMMDD}-@var{HHMMSS}.log} in the current
directory.
This file can be useful for bug reports.
-It also implies @code{-loglevel verbose}.
+It also implies @code{-loglevel debug}.
Setting the environment variable @env{FFREPORT} to any value has the
same effect. If the value is a ':'-separated key=value sequence, these
@end example
All codec AVOptions are per-stream, and thus a stream specifier
-should be attached to them.
+should be attached to them:
+@example
+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
+@end example
+
+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 @option{-nooption} syntax cannot be used for boolean
AVOptions, use @option{-option 0}/@option{-option 1}.
projects / ffmpeg / blobdiff