---
doc/encoders.texi | 5 +++++
libavcodec/libopusenc.c | 9 +++++++++
2 files changed, 14 insertions(+)
diff --git a/doc/encoders.texi b/doc/encoders.texi
index 69bf742c2d..a48b15eb1b 100644
--- a/doc/encoders.texi
+++ b/doc/encoders.texi
@@ -953,6 +953,11 @@ The default is 20ms.
@item packet_loss (@emph{expect-loss})
Set expected packet loss percentage. The default is 0.
+@item fec (@emph{n/a})
+Enable inband forward error correction. @option{packet_loss} must be non-zero
+to take advantage - frequency of FEC 'side-data' is proportional to expected
packet loss.
+Default is disabled.
+
@item application (N.A.)
Set intended application type. Valid options are listed below:
diff --git a/libavcodec/libopusenc.c b/libavcodec/libopusenc.c
index 13017ac323..bf2d04b4fb 100644
--- a/libavcodec/libopusenc.c
+++ b/libavcodec/libopusenc.c
@@ -34,6 +34,7 @@ typedef struct LibopusEncOpts {
int vbr;
int application;
int packet_loss;
+ int fec;
int complexity;
float frame_duration;
int packet_size;
@@ -149,6 +150,13 @@ static int libopus_configure_encoder(AVCodecContext
*avctx, OpusMSEncoder *enc,
"Unable to set expected packet loss percentage: %s\n",
opus_strerror(ret));
+ ret = opus_multistream_encoder_ctl(enc,
+ OPUS_SET_INBAND_FEC(opts->fec));
+ if (ret != OPUS_OK)
+ av_log(avctx, AV_LOG_WARNING,
+ "Unable to set inband FEC: %s\n",
+ opus_strerror(ret));
+
if (avctx->cutoff) {
ret = opus_multistream_encoder_ctl(enc,
OPUS_SET_MAX_BANDWIDTH(opts->max_bandwidth));
@@ -544,6 +552,7 @@ static const AVOption libopus_options[] = {
{ "lowdelay", "Restrict to only the lowest delay modes", 0,
AV_OPT_TYPE_CONST, { .i64 = OPUS_APPLICATION_RESTRICTED_LOWDELAY }, 0, 0, FLAGS, "application" },
{ "frame_duration", "Duration of a frame in milliseconds",
OFFSET(frame_duration), AV_OPT_TYPE_FLOAT, { .dbl = 20.0 }, 2.5, 120.0, FLAGS },
{ "packet_loss", "Expected packet loss percentage",
OFFSET(packet_loss), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 100, FLAGS },
+ { "fec", "Enable inband FEC. Expected packet loss must be
non-zero", OFFSET(fec), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
{ "vbr", "Variable bit rate mode", OFFSET(vbr),
AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 2, FLAGS, "vbr" },
{ "off", "Use constant bit rate", 0, AV_OPT_TYPE_CONST, { .i64 = 0
}, 0, 0, FLAGS, "vbr" },
{ "on", "Use variable bit rate", 0, AV_OPT_TYPE_CONST, { .i64 = 1
}, 0, 0, FLAGS, "vbr" },
