lavc/codec_par: add AVCodecParameters.framerate

This corresponds to AVCodecContext.framerate.

doc/APIchanges

@@ -2,6 +2,9 @@ The last version increases of all libraries were on 2023-02-09
 
 API changes, most recent first:
 
+2023-05-xx - xxxxxxxxxx - lavc 60.11.100 - codec_par.h
+  Add AVCodecParameters.framerate.
+
 2023-05-04 - xxxxxxxxxx - lavu 58.7.100 - frame.h
   Deprecate AVFrame.interlaced_frame, AVFrame.top_field_first, and
   AVFrame.key_frame.

libavcodec/codec_par.c

@@ -46,6 +46,7 @@ static void codec_parameters_reset(AVCodecParameters *par)
     par->color_space         = AVCOL_SPC_UNSPECIFIED;
     par->chroma_location     = AVCHROMA_LOC_UNSPECIFIED;
     par->sample_aspect_ratio = (AVRational){ 0, 1 };
+    par->framerate           = (AVRational){ 0, 1 };
     par->profile             = FF_PROFILE_UNKNOWN;
     par->level               = FF_LEVEL_UNKNOWN;
 }
@@ -126,6 +127,7 @@ int avcodec_parameters_from_context(AVCodecParameters *par,
         par->chroma_location     = codec->chroma_sample_location;
         par->sample_aspect_ratio = codec->sample_aspect_ratio;
         par->video_delay         = codec->has_b_frames;
+        par->framerate           = codec->framerate;
         break;
     case AVMEDIA_TYPE_AUDIO:
         par->format           = codec->sample_fmt;
@@ -207,6 +209,7 @@ int avcodec_parameters_to_context(AVCodecContext *codec,
         codec->chroma_sample_location = par->chroma_location;
         codec->sample_aspect_ratio    = par->sample_aspect_ratio;
         codec->has_b_frames           = par->video_delay;
+        codec->framerate              = par->framerate;
         break;
     case AVMEDIA_TYPE_AUDIO:
         codec->sample_fmt       = par->format;

libavcodec/codec_par.h

@@ -211,6 +211,18 @@ typedef struct AVCodecParameters {
      * Audio only. The channel layout and number of channels.
      */
     AVChannelLayout ch_layout;
+
+    /**
+     * Video only. Number of frames per second, for streams with constant frame
+     * durations. Should be set to { 0, 1 } when some frames have differing
+     * durations or if the value is not known.
+     *
+     * @note This field correponds to values that are stored in codec-level
+     * headers and is typically overridden by container/transport-layer
+     * timestamps, when available. It should thus be used only as a last resort,
+     * when no higher-level timing information is available.
+     */
+    AVRational framerate;
 } AVCodecParameters;
 
 /**

libavcodec/version.h

@@ -29,7 +29,7 @@
 
 #include "version_major.h"
 
-#define LIBAVCODEC_VERSION_MINOR  10
+#define LIBAVCODEC_VERSION_MINOR  11
 #define LIBAVCODEC_VERSION_MICRO 100
 
 #define LIBAVCODEC_VERSION_INT  AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \