Revert "lavc: remove FF_API_RATE_EMU cruft"

This reverts commit 694c142434.

libavcodec/avcodec.h

@@ -1226,6 +1226,16 @@ typedef struct AVCodecContext {
      */
     enum PixelFormat pix_fmt;
 
+#if FF_API_RATE_EMU
+    /**
+     * Frame rate emulation. If not zero, the lower layer (i.e. format handler)
+     * has to read frames at native frame rate.
+     * - encoding: Set by user.
+     * - decoding: unused
+     */
+    attribute_deprecated int rate_emu;
+#endif
+
     /**
      * If non NULL, 'draw_horiz_band' is called by the libavcodec
      * decoder to draw a horizontal band. It improves cache usage. Not

libavcodec/options.c

@@ -105,6 +105,9 @@ static const AVOption options[]={
 {"extradata_size", NULL, OFFSET(extradata_size), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX},
 {"time_base", NULL, OFFSET(time_base), FF_OPT_TYPE_RATIONAL, DEFAULT, INT_MIN, INT_MAX},
 {"g", "set the group of picture size", OFFSET(gop_size), FF_OPT_TYPE_INT, 12, INT_MIN, INT_MAX, V|E},
+#if FF_API_RATE_EMU
+{"rate_emu", "frame rate emulation", OFFSET(rate_emu), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX},
+#endif
 {"ar", "set audio sampling rate (in Hz)", OFFSET(sample_rate), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX},
 {"ac", "set number of audio channels", OFFSET(channels), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX},
 {"cutoff", "set cutoff bandwidth", OFFSET(cutoff), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, A|E},

libavcodec/version.h

@@ -71,6 +71,9 @@
 #ifndef FF_API_OLD_AUDIOCONVERT
 #define FF_API_OLD_AUDIOCONVERT (LIBAVCODEC_VERSION_MAJOR < 54)
 #endif
+#ifndef FF_API_RATE_EMU
+#define FF_API_RATE_EMU         (LIBAVCODEC_VERSION_MAJOR < 53)
+#endif
 #ifndef FF_API_MB_Q
 #define FF_API_MB_Q             (LIBAVCODEC_VERSION_MAJOR < 53)
 #endif