ffmpeg: add enc_time_base option

add a per-stream option for setting the encoder timebase.
the following values are allowed:
0 - for video, use 1/frame_rate, for audio use 1/sample_rate (this is
  the default)
-1 - match the input timebase (when possible)
>0 - set the timebase to provided number

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

1 files changed, 3 insertions, 0 deletions

diff --git a/ffmpeg.h b/ffmpeg.h
index d34561275a..854ed1924a 100644
--- a/ffmpeg.h
+++ b/ffmpeg.h
@@ -226,6 +226,8 @@ typedef struct OptionsContext {
     int        nb_program;
     SpecifierOpt *time_bases;
     int        nb_time_bases;
+    SpecifierOpt *enc_time_bases;
+    int        nb_enc_time_bases;
 } OptionsContext;
 
 typedef struct InputFilter {
@@ -453,6 +455,7 @@ typedef struct OutputStream {
     int64_t last_mux_dts;
     // the timebase of the packets sent to the muxer
     AVRational mux_timebase;
+    AVRational enc_timebase;
 
     int                    nb_bitstream_filters;
     uint8_t                  *bsf_extradata_updated;