lavc: deprecate FF_IDCT_NONE

It was only used by XvMC.

libavcodec/avcodec.h

@@ -1407,7 +1407,10 @@ typedef struct AVCodecContext {
 #define FF_IDCT_SIMPLEARMV6   17
 #define FF_IDCT_FAAN          20
 #define FF_IDCT_SIMPLENEON    22
-#define FF_IDCT_NONE          24 /* Used by XvMC to extract IDCT coefficients with FF_IDCT_PERM_NONE */
+#if FF_API_IDCT_NONE
+// formerly used by xvmc
+#define FF_IDCT_NONE          24
+#endif
 #define FF_IDCT_SIMPLEAUTO    128
 
     /**

libavcodec/idctdsp.c

@@ -287,7 +287,6 @@ av_cold void ff_idctdsp_init(IDCTDSPContext *c, AVCodecContext *avctx)
                 c->perm_type = FF_IDCT_PERM_NONE;
 #endif /* CONFIG_FAANIDCT */
             } else { // accurate/default
-                /* Be sure FF_IDCT_NONE will select this one, since it uses FF_IDCT_PERM_NONE */
                 c->idct_put  = ff_simple_idct_put_int16_8bit;
                 c->idct_add  = ff_simple_idct_add_int16_8bit;
                 c->idct      = ff_simple_idct_int16_8bit;

libavcodec/version.h

@@ -64,5 +64,6 @@
 #define FF_API_FLAG_TRUNCATED      (LIBAVCODEC_VERSION_MAJOR < 60)
 #define FF_API_SUB_TEXT_FORMAT     (LIBAVCODEC_VERSION_MAJOR < 60)
 #define FF_API_MJPEG_PRED          (LIBAVCODEC_VERSION_MAJOR < 60)
+#define FF_API_IDCT_NONE           (LIBAVCODEC_VERSION_MAJOR < 60)
 
 #endif /* AVCODEC_VERSION_H */