libsvtav1: Fix the documentation to match the actual options

doc/encoders.texi

@@ -1687,7 +1687,7 @@ Enable smooth interintra mode. Default is true.
 
 @end table
 
-@section libsvt-av1
+@section libsvtav1
 
 SVT-AV1 encoder wrapper.
 
@@ -1697,31 +1697,55 @@ You need to explicitly configure the build with @code{--enable-libsvtav1}.
 @subsection Options
 
 @table @option
+@item profile
+Set the encoding profile.
+
+@item level
+Set the operating point level.
+
+@item tier
+Set the operating point tier.
+
+@item rc
+Set the rate control mode to use.
+
+Possible modes:
+@table @option
+@item cqp
+Constant quantizer: use fixed values of qindex (dependent on the frame type)
+throughout the stream.  This mode is the default.
+
+@item vbr
+Variable bitrate: use a target bitrate for the whole stream.
+
+@item cvbr
+Constrained variable bitrate: use a target bitrate for each GOP.
+@end table
+
 @item qmax
-Sets the maximum quantizer to use when using bitrate mode.
+Set the maximum quantizer to use when using a bitrate mode.
 
 @item qmin
-Sets the minimum quantizer to use when using bitrate mode.
+Set the minimum quantizer to use when using a bitrate mode.
 
 @item qp
-Uses quantizer mode to encode at the given quantizer (0-63).
+Set the quantizer used in cqp rate control mode (0-63).
 
-@item hielevel
+@item sc_detection
 Enable scene change detection.
 
 @item la_depth
 Set number of frames to look ahead (0-120).
 
 @item preset
-Set encoding preset.
+Set the quality-speed tradeoff, in the range 0 to 8.  Higher values are
+faster but lower quality.  Defaults to 8 (highest speed).
 
-@item tier
-
-@item tile-rows
-Selects how many rows of tiles to encode with (0-6).
+@item tile_rows
+Set log2 of the number of rows of tiles to use (0-6).
 
-@item tile-columns
-Selects how many columns of tiles to encode with (0-4).
+@item tile_columns
+Set log2 of the number of columns of tiles to use (0-4).
 
 @end table
 

libavcodec/libsvtav1.c

@@ -489,7 +489,7 @@ static const AVOption options[] = {
     { "preset", "Encoding preset [0, 8]",
       OFFSET(enc_mode), AV_OPT_TYPE_INT, { .i64 = MAX_ENC_PRESET }, 0, MAX_ENC_PRESET, VE },
 
-    { "tier", "Set tier (general_tier_flag)", OFFSET(tier),
+    { "tier", "Set operating point tier", OFFSET(tier),
       AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, VE, "tier" },
         { "main", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 0 }, 0, 0, VE, "tier" },
         { "high", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 1 }, 0, 0, VE, "tier" },
@@ -526,11 +526,11 @@ static const AVOption options[] = {
 
     { "rc", "Bit rate control mode", OFFSET(rc_mode),
       AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 3, VE , "rc"},
-        { "cqp", "Const Quantization Parameter", 0, AV_OPT_TYPE_CONST, { .i64 = 0 },  INT_MIN, INT_MAX, VE, "rc" },
+        { "cqp", "Constant quantizer", 0, AV_OPT_TYPE_CONST, { .i64 = 0 },  INT_MIN, INT_MAX, VE, "rc" },
         { "vbr", "Variable Bit Rate, use a target bitrate for the entire stream", 0, AV_OPT_TYPE_CONST, { .i64 = 1 },  INT_MIN, INT_MAX, VE, "rc" },
         { "cvbr", "Constrained Variable Bit Rate, use a target bitrate for each GOP", 0, AV_OPT_TYPE_CONST,{ .i64 = 2 },  INT_MIN, INT_MAX, VE, "rc" },
 
-    { "qp", "QP value for intra frames", OFFSET(qp),
+    { "qp", "Quantizer to use with cqp rate control mode", OFFSET(qp),
       AV_OPT_TYPE_INT, { .i64 = 50 }, 0, 63, VE },
 
     { "sc_detection", "Scene change detection", OFFSET(scd),