Allow strings for variable names in ffmpeg encoder.

savonet · Feb 29, 2020 · f51f080 · f51f080
1 parent f8a9536
commit f51f080
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Showing 2 changed files with 15 additions and 4 deletions.
diff --git a/doc/content/encoding_formats.md b/doc/content/encoding_formats.md
@@ -143,7 +143,9 @@ The encoder should support all the options for `ffmpeg`'s [muxers](https://ffmpe
 ```liquidsoap
 %ffmpeg(format="mpegts",
         %audio(codec="ac3",channel_coupling=0),
-        %video(codec="libx264",b="2600k",preset="ultrafast"))
+        %video(codec="libx264",b="2600k",
+               "x264-params"="scenecut=0:open_gop=0:min-keyint=150:keyint=150",
+               preset="ultrafast"))
 ```
 
 The full syntax is as follows:
@@ -161,6 +163,7 @@ Where:
 
 * `<format>` is either a string value (e.g. `"mpegts"`), as returned by the `ffmpeg -formats` command or `none`. When set to `none` or simply no specified, the encoder will try to auto-detect it.
 * `<codec>` is either a string value (e.g. `"libmp3lame"`), as returned by the `ffmpeg -codecs` command or `none`. When set to `none`, for audio, `channels` is set to `0` and, for either audio or video, the stream is assumed to have no such content.
+* `<option_name>` can be any syntactically valid variable name or string. Strings are typically used when the option name is of the form: `foo-bar`.
 * `%audio(..)` is for options specific to the audio codec. Unused options will raise an exception. Any option supported by `ffmpeg` can be passed here.
 * `%video(..)` is for options specific to the video codec. Unused options will raise an exception. Any option supported by `ffmpeg` can be passed here.
 * Generic options are passed to audio, video and format (container) setup. Unused options will raise an exception. Any option supported by `ffmpeg` can be passed here. 

diff --git a/src/lang/lang_parser.mly b/src/lang/lang_parser.mly
@@ -446,10 +446,18 @@ ogg_item:
   | FLAC app_opt       { Lang_flac.make_ogg $2 }
   | top_level_ogg_item { $1 }
 
+ffmpeg_param:
+  | STRING GETS expr { $1,$3 }
+  | VAR GETS expr        { $1,$3 }
+ffmpeg_params:
+  |                                  { [] }
+  | ffmpeg_param                     { [$1] }
+  | ffmpeg_param COMMA ffmpeg_params { $1::$3 }
+
 ffmpeg_list_elem:
-  | AUDIO LPAR app_list RPAR { `Audio  $3 }
-  | VIDEO LPAR app_list RPAR { `Video  $3 }
-  | VAR GETS expr { `Option ($1,$3) }
+  | AUDIO LPAR ffmpeg_params RPAR { `Audio  $3 }
+  | VIDEO LPAR ffmpeg_params RPAR { `Video  $3 }
+  | ffmpeg_param                  { `Option $1 }
 ffmpeg_list:
   |                                    { [] }
   | ffmpeg_list_elem                   { [$1] }