mpegvideo: Expand macro

Having this macro in an header only facilitates the use of such header.
The code increase is minimal and files have one less dependency
on mpegvideo.h.

libavcodec/flvenc.c

@@ -91,7 +91,12 @@ void ff_flv2_encode_ac_esc(PutBitContext *pb, int slevel, int level,
     }
 }
 
-FF_MPV_GENERIC_CLASS(flv)
+static const AVClass flv_class = {
+    .class_name = "flv encoder",
+    .item_name  = av_default_item_name,
+    .option     = ff_mpv_generic_options,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
 
 AVCodec ff_flv_encoder = {
     .name           = "flv",

libavcodec/h261enc.c

@@ -324,7 +324,12 @@ av_cold void ff_h261_encode_init(MpegEncContext *s)
     s->c_dc_scale_table = ff_mpeg1_dc_scale_table;
 }
 
-FF_MPV_GENERIC_CLASS(h261)
+static const AVClass h261_class = {
+    .class_name = "h261 encoder",
+    .item_name  = av_default_item_name,
+    .option     = ff_mpv_generic_options,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
 
 AVCodec ff_h261_encoder = {
     .name           = "h261",

libavcodec/mpegvideo.h

@@ -574,14 +574,6 @@ typedef struct MpegEncContext {
 
 extern const AVOption ff_mpv_generic_options[];
 
-#define FF_MPV_GENERIC_CLASS(name) \
-static const AVClass name ## _class = {\
-    .class_name = #name " encoder",\
-    .item_name  = av_default_item_name,\
-    .option     = ff_mpv_generic_options,\
-    .version    = LIBAVUTIL_VERSION_INT,\
-};
-
 /**
  * Set the given MpegEncContext to common defaults (same for encoding
  * and decoding).  The changed fields will not depend upon the prior

libavcodec/mpegvideo_enc.c

@@ -4374,7 +4374,12 @@ AVCodec ff_h263p_encoder = {
     .priv_class     = &h263p_class,
 };
 
-FF_MPV_GENERIC_CLASS(msmpeg4v2)
+static const AVClass msmpeg4v2_class = {
+    .class_name = "msmpeg4v2 encoder",
+    .item_name  = av_default_item_name,
+    .option     = ff_mpv_generic_options,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
 
 AVCodec ff_msmpeg4v2_encoder = {
     .name           = "msmpeg4v2",
@@ -4389,7 +4394,12 @@ AVCodec ff_msmpeg4v2_encoder = {
     .priv_class     = &msmpeg4v2_class,
 };
 
-FF_MPV_GENERIC_CLASS(msmpeg4v3)
+static const AVClass msmpeg4v3_class = {
+    .class_name = "msmpeg4v3 encoder",
+    .item_name  = av_default_item_name,
+    .option     = ff_mpv_generic_options,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
 
 AVCodec ff_msmpeg4v3_encoder = {
     .name           = "msmpeg4",
@@ -4404,7 +4414,12 @@ AVCodec ff_msmpeg4v3_encoder = {
     .priv_class     = &msmpeg4v3_class,
 };
 
-FF_MPV_GENERIC_CLASS(wmv1)
+static const AVClass wmv1_class = {
+    .class_name = "wmv1 encoder",
+    .item_name  = av_default_item_name,
+    .option     = ff_mpv_generic_options,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
 
 AVCodec ff_wmv1_encoder = {
     .name           = "wmv1",

libavcodec/rv10enc.c

@@ -63,7 +63,12 @@ int ff_rv10_encode_picture_header(MpegEncContext *s, int picture_number)
     return 0;
 }
 
-FF_MPV_GENERIC_CLASS(rv10)
+static const AVClass rv10_class = {
+    .class_name = "rv10 encoder",
+    .item_name  = av_default_item_name,
+    .option     = ff_mpv_generic_options,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
 
 AVCodec ff_rv10_encoder = {
     .name           = "rv10",

libavcodec/rv20enc.c

@@ -60,7 +60,12 @@ void ff_rv20_encode_picture_header(MpegEncContext *s, int picture_number){
     }
 }
 
-FF_MPV_GENERIC_CLASS(rv20)
+static const AVClass rv20_class = {
+    .class_name = "rv20 encoder",
+    .item_name  = av_default_item_name,
+    .option     = ff_mpv_generic_options,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
 
 AVCodec ff_rv20_encoder = {
     .name           = "rv20",