doc: fix various typos and grammar errors

Signed-off-by: Moritz Barsnick <barsnick@gmx.net>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

doc/codecs.texi

@@ -1226,7 +1226,7 @@ Set to 1 to disable processing alpha (transparency). This works like the
 instead of alpha. Default is 0.
 
 @item codec_whitelist @var{list} (@emph{input})
-"," separated List of allowed decoders. By default all are allowed.
+"," separated list of allowed decoders. By default all are allowed.
 
 @item dump_separator @var{string} (@emph{input})
 Separator used to separate the fields printed on the command line about the

doc/demuxers.texi

@@ -72,7 +72,7 @@ Do not try to resynchronize by looking for a certain optional start code.
 Virtual concatenation script demuxer.
 
 This demuxer reads a list of files and other directives from a text file and
-demuxes them one after the other, as if all their packet had been muxed
+demuxes them one after the other, as if all their packets had been muxed
 together.
 
 The timestamps in the files are adjusted so that the first file starts at 0
@@ -107,7 +107,7 @@ Identify the script type and version. It also sets the @option{safe} option
 to 1 if it was -1.
 
 To make FFmpeg recognize the format automatically, this directive must
-appears exactly as is (no extra space or byte-order-mark) on the very first
+appear exactly as is (no extra space or byte-order-mark) on the very first
 line of the script.
 
 @item @code{duration @var{dur}}

doc/ffmpeg.texi

@@ -1008,7 +1008,7 @@ Dump each input packet to stderr.
 @item -hex (@emph{global})
 When dumping packets, also dump the payload.
 @item -re (@emph{input})
-Read input at native frame rate. Mainly used to simulate a grab device.
+Read input at native frame rate. Mainly used to simulate a grab device,
 or live input stream (e.g. when reading from a file). Should not be used
 with actual grab devices or live input streams (where it can cause packet
 loss).

doc/fftools-common-opts.texi

@@ -176,10 +176,10 @@ loglevel will be used. If multiple loglevel parameters are given, using
 Show nothing at all; be silent.
 @item panic, 0
 Only show fatal errors which could lead the process to crash, such as
-and assert failure. This is not currently used for anything.
+an assertion failure. This is not currently used for anything.
 @item fatal, 8
 Only show fatal errors. These are errors after which the process absolutely
-cannot continue after.
+cannot continue.
 @item error, 16
 Show all errors, including ones which can be recovered from.
 @item warning, 24
@@ -195,13 +195,13 @@ Show everything, including debugging information.
 @item trace, 56
 @end table
 
-By default the program logs to stderr, if coloring is supported by the
+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
 @env{AV_LOG_FORCE_NOCOLOR} or @env{NO_COLOR}, or can be forced setting
 the environment variable @env{AV_LOG_FORCE_COLOR}.
 The use of the environment variable @env{NO_COLOR} is deprecated and
-will be dropped in a following FFmpeg version.
+will be dropped in a future FFmpeg version.
 
 @item -report
 Dump full command line and console output to a file named

doc/filters.texi

@@ -911,14 +911,14 @@ A gate is mainly used to reduce lower parts of a signal. This kind of signal
 processing reduces disturbing noise between useful signals.
 
 Gating is done by detecting the volume below a chosen level @var{threshold}
-and divide it by the factor set with @var{ratio}. The bottom of the noise
+and dividing it by the factor set with @var{ratio}. The bottom of the noise
 floor is set via @var{range}. Because an exact manipulation of the signal
 would cause distortion of the waveform the reduction can be levelled over
 time. This is done by setting @var{attack} and @var{release}.
 
 @var{attack} determines how long the signal has to fall below the threshold
 before any reduction will occur and @var{release} sets the time the signal
-has to raise above the threshold to reduce the reduction again.
+has to rise above the threshold to reduce the reduction again.
 Shorter signals than the chosen attack time will be left untouched.
 
 @table @option
@@ -935,7 +935,7 @@ If a signal rises above this level the gain reduction is released.
 Default is 0.125. Allowed range is from 0 to 1.
 
 @item ratio
-Set a ratio about which the signal is reduced.
+Set a ratio by which the signal is reduced.
 Default is 2. Allowed range is from 1 to 9000.
 
 @item attack
@@ -958,19 +958,19 @@ Default is 2.828427125. Allowed range is from 1 to 8.
 
 @item detection
 Choose if exact signal should be taken for detection or an RMS like one.
-Default is rms. Can be peak or rms.
+Default is @code{rms}. Can be @code{peak} or @code{rms}.
 
 @item link
 Choose if the average level between all channels or the louder channel affects
 the reduction.
-Default is average. Can be average or maximum.
+Default is @code{average}. Can be @code{average} or @code{maximum}.
 @end table
 
 @section alimiter
 
-The limiter prevents input signal from raising over a desired threshold.
+The limiter prevents an input signal from rising over a desired threshold.
 This limiter uses lookahead technology to prevent your signal from distorting.
-It means that there is a small delay after signal is processed. Keep in mind
+It means that there is a small delay after the signal is processed. Keep in mind
 that the delay it produces is the attack time you set.
 
 The filter accepts the following options:
@@ -1453,7 +1453,7 @@ Set the number of samples per each output audio frame.
 
 The last output packet may contain a different number of samples, as
 the filter will flush all the remaining samples when the input audio
-signal its end.
+signals its end.
 
 The filter accepts the following options:
 
@@ -2559,7 +2559,7 @@ filtering with large delay. Default is disabled.
 Enable multichannels evaluation on gain. Default is disabled.
 
 @item zero_phase
-Enable zero phase mode by substracting timestamp to compensate delay.
+Enable zero phase mode by subtracting timestamp to compensate delay.
 Default is disabled.
 @end table
 
@@ -3388,7 +3388,7 @@ Can be specified in dB (in case "dB" is appended to the specified value)
 or amplitude ratio. Default value is @code{0}.
 
 @item leave_silence
-This indicate that @var{stop_duration} length of audio should be left intact
+This indicates that @var{stop_duration} length of audio should be left intact
 at the beginning of each period of silence.
 For example, if you want to remove long pauses between words but do not want
 to remove the pauses completely. Default value is @code{0}.
@@ -6721,10 +6721,10 @@ This option does not exist, please see the timeline system
 
 @item alpha
 Draw the text applying alpha blending. The value can
-be either a number between 0.0 and 1.0
-The expression accepts the same variables @var{x, y} do.
+be a number between 0.0 and 1.0.
+The expression accepts the same variables @var{x, y} as well.
 The default value is 1.
-Please see fontcolor_expr
+Please see @var{fontcolor_expr}.
 
 @item fontsize
 The font size to be used for drawing text.
@@ -6907,7 +6907,7 @@ the following expansion mechanism is used.
 The backslash character @samp{\}, followed by any character, always expands to
 the second character.
 
-Sequence of the form @code{%@{...@}} are expanded. The text between the
+Sequences of the form @code{%@{...@}} are expanded. The text between the
 braces is a function name, possibly followed by arguments separated by ':'.
 If the arguments contain special characters or delimiters (':' or '@}'),
 they should be escaped.
@@ -8854,8 +8854,8 @@ By default value is 0.
 
 Detect video interlacing type.
 
-This filter tries to detect if the input frames as interlaced, progressive,
-top or bottom field first. It will also try and detect fields that are
+This filter tries to detect if the input frames are interlaced, progressive,
+top or bottom field first. It will also try to detect fields that are
 repeated between adjacent frames (a sign of telecine).
 
 Single frame detection considers only immediately adjacent frames when classifying each frame.
@@ -8922,7 +8922,7 @@ Set progressive threshold.
 Threshold for repeated field detection.
 @item half_life
 Number of frames after which a given frame's contribution to the
-statistics is halved (i.e., it contributes only 0.5 to it's
+statistics is halved (i.e., it contributes only 0.5 to its
 classification). The default of 0 means that all frames seen are given
 full weight of 1.0 forever.
 @item analyze_interlaced_flag
@@ -14822,7 +14822,7 @@ syntax is deprecated:
 Create a pattern generated by an elementary cellular automaton.
 
 The initial state of the cellular automaton can be defined through the
-@option{filename}, and @option{pattern} options. If such options are
+@option{filename} and @option{pattern} options. If such options are
 not specified an initial state is created randomly.
 
 At each new frame a new row in the video is filled with the result of
@@ -15993,7 +15993,7 @@ Temporally interleave frames from several inputs.
 These filters read frames from several inputs and send the oldest
 queued frame to the output.
 
-Input streams must have a well defined, monotonically increasing frame
+Input streams must have well defined, monotonically increasing frame
 timestamp values.
 
 In order to submit one frame to output, these filters need to enqueue
@@ -16001,9 +16001,9 @@ at least one frame for each input, so they cannot work in case one
 input is not yet terminated and will not receive incoming frames.
 
 For example consider the case when one input is a @code{select} filter
-which always drop input frames. The @code{interleave} filter will keep
+which always drops input frames. The @code{interleave} filter will keep
 reading from that input, but it will never be able to send new frames
-to output until the input will send an end-of-stream signal.
+to output until the input sends an end-of-stream signal.
 
 Also, depending on inputs synchronization, the filters will drop
 frames in case one input receives more frames than the other ones, and

doc/formats.texi

@@ -199,7 +199,7 @@ delayed bt the time duration specified in @var{offset}. Default value
 is @code{0} (meaning that no offset is applied).
 
 @item format_whitelist @var{list} (@emph{input})
-"," separated List of allowed demuxers. By default all are allowed.
+"," separated list of allowed demuxers. By default all are allowed.
 
 @item dump_separator @var{string} (@emph{input})
 Separator used to separate the fields printed on the command line about the

doc/indevs.texi

@@ -678,7 +678,7 @@ is an exact value. For HDV, it is not frame exact, since HDV does
 not have a fixed frame size.
 
 @item dvguid
-Select the capture device by specifying it's GUID. Capturing will only
+Select the capture device by specifying its GUID. Capturing will only
 be performed from the specified device and fails if no device with the
 given GUID is found. This is useful to select the input if multiple
 devices are connected at the same time.
@@ -1341,7 +1341,7 @@ ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
 
 @table @option
 @item draw_mouse
-Specify whether to draw the mouse pointer. A value of @code{0} specify
+Specify whether to draw the mouse pointer. A value of @code{0} specifies
 not to draw the pointer. Default value is @code{1}.
 
 @item follow_mouse

doc/muxers.texi

@@ -295,14 +295,14 @@ the loops:
 ffmpeg -i INPUT -loop 10 -final_delay 500 out.gif
 @end example
 
-Note 1: if you wish to extract the frames in separate GIF files, you need to
+Note 1: if you wish to extract the frames into separate GIF files, you need to
 force the @ref{image2} muxer:
 @example
 ffmpeg -i INPUT -c:v gif -f image2 "out%d.gif"
 @end example
 
-Note 2: the GIF format has a very small time base: the delay between two frames
-can not be smaller than one centi second.
+Note 2: the GIF format has a very large time base: the delay between two frames
+can therefore not be smaller than one centi second.
 
 @anchor{hash}
 @section hash

doc/platform.texi

@@ -173,7 +173,7 @@ earlier, place @code{c99wrap.exe} and @code{c99conv.exe} somewhere in your
 Next, make sure any other headers and libs you want to use, such as zlib, are
 located in a spot that the compiler can see. Do so by modifying the @code{LIB}
 and @code{INCLUDE} environment variables to include the @strong{Windows-style}
-paths to these directories. Alternatively, you can try and use the
+paths to these directories. Alternatively, you can try to use the
 @code{--extra-cflags}/@code{--extra-ldflags} configure options. If using MSVC
 2012 or earlier, place @code{inttypes.h} somewhere the compiler can see too.
 

doc/protocols.texi

@@ -357,7 +357,7 @@ autodetection in the future.
 If set to 1 enables experimental HTTP server. This can be used to send data when
 used as an output option, or read data from a client with HTTP POST when used as
 an input option.
-If set to 2 enables experimental mutli-client HTTP server. This is not yet implemented
+If set to 2 enables experimental multi-client HTTP server. This is not yet implemented
 in ffmpeg.c or ffserver.c and thus must not be used as a command line option.
 @example
 # Server side (sending):