doc: libmodplug

Add entry in external library list and demuxers.

doc/demuxers.texi

@@ -502,6 +502,64 @@ Default is 50 MiB.
 
 @end table
 
+@section libmodplug
+
+ModPlug based module demuxer
+
+See @url{https://github.com/Konstanty/libmodplug}
+
+It will export one 2-channel 16-bit 44.1 kHz audio stream.
+Optionally, a @code{pal8} 16-color video stream can be exported with or without printed metadata.
+
+It accepts the following options:
+
+@table @option
+@item noise_reduction
+Apply a simple low-pass filter. Can be 1 (on) or 0 (off). Default is 0.
+
+@item reverb_depth
+Set amount of reverb. Range 0-100. Default is 0.
+
+@item reverb_delay
+Set delay in ms, clamped to 40-250 ms. Default is 0.
+
+@item bass_amount
+Apply bass expansion a.k.a. XBass or megabass. Range is 0 (quiet) to 100 (loud). Default is 0.
+
+@item bass_range
+Set cutoff i.e. upper-bound for bass frequencies. Range is 10-100 Hz. Default is 0.
+
+@item surround_depth
+Apply a Dolby Pro-Logic surround effect. Range is 0 (quiet) to 100 (heavy). Default is 0.
+
+@item surround_delay
+Set surround delay in ms, clamped to 5-40 ms. Default is 0.
+
+@item max_size
+The demuxer buffers the entire file into memory. Adjust this value to set the maximum buffer size,
+which in turn, acts as a ceiling for the size of files that can be read. Range is 0 to 100 MiB.
+0 removes buffer size limit (not recommended). Default is 5 MiB.
+
+@item video_stream_expr
+String which is evaluated using the eval API to assign colors to the generated video stream.
+Variables which can be used are @code{x}, @code{y}, @code{w}, @code{h}, @code{t}, @code{speed},
+@code{tempo}, @code{order}, @code{pattern} and @code{row}.
+
+@item video_stream
+Generate video stream. Can be 1 (on) or 0 (off). Default is 0.
+
+@item video_stream_w
+Set video frame width in 'chars' where one char indicates 8 pixels. Range is 20-512. Default is 30.
+
+@item video_stream_h
+Set video frame height in 'chars' where one char indicates 8 pixels. Range is 20-512. Default is 30.
+
+@item video_stream_ptxt
+Print metadata on video stream. Includes @code{speed}, @code{tempo}, @code{order}, @code{pattern},
+@code{row} and @code{ts} (time in ms). Can be 1 (on) or 0 (off). Default is 1.
+
+@end table
+
 @section libopenmpt
 
 libopenmpt based module demuxer

doc/general.texi

@@ -65,6 +65,12 @@ FFmpeg can make use of the Game Music Emu library to read audio from supported v
 music file formats. Pass @code{--enable-libgme} to configure to
 enable it. See @url{https://bitbucket.org/mpyne/game-music-emu/overview}.
 
+@section ModPlug
+
+FFmpeg can make use of this library, originating in Modplug-XMMS, to read from MOD-like music files.
+See @url{https://github.com/Konstanty/libmodplug}. Pass @code{--enable-libmodplug} to configure to
+enable it.
+
 @section OpenJPEG
 
 FFmpeg can use the OpenJPEG libraries for encoding/decoding J2K videos.  Go to
@@ -72,7 +78,6 @@ FFmpeg can use the OpenJPEG libraries for encoding/decoding J2K videos.  Go to
 instructions.  To enable using OpenJPEG in FFmpeg, pass @code{--enable-libopenjpeg} to
 @file{./configure}.
 
-
 @section OpenCORE, VisualOn, and Fraunhofer libraries
 
 Spun off Google Android sources, OpenCore, VisualOn and Fraunhofer