doxy: add ref for lavfi, lpp and lsws.

libavfilter/avfilter.h

@@ -22,6 +22,17 @@
 #ifndef AVFILTER_AVFILTER_H
 #define AVFILTER_AVFILTER_H
 
+/**
+ * @file
+ * @ingroup lavfi
+ * external API header
+ */
+
+/**
+ * @defgroup lavfi Libavfilter
+ * @{
+ */
+
 #include <stddef.h>
 
 #include "libavutil/avutil.h"
@@ -840,4 +851,8 @@ void avfilter_free(AVFilterContext *filter);
 int avfilter_insert_filter(AVFilterLink *link, AVFilterContext *filt,
                            unsigned filt_srcpad_idx, unsigned filt_dstpad_idx);
 
+/**
+ * @}
+ */
+
 #endif /* AVFILTER_AVFILTER_H */

libavutil/avutil.h

@@ -35,13 +35,13 @@
  * provided by FFmpeg.
  *
  * @li @ref libavc "libavcodec" encoding/decoding library
- * @li @subpage libavfilter graph based frame editing library
+ * @li @ref lavfi "libavfilter" graph based frame editing library
  * @li @ref libavf "libavformat" I/O and muxing/demuxing library
  * @li @ref lavd "libavdevice" special devices muxing/demuxing library
  * @li @ref lavu "libavutil" common utility library
  * @li @ref lswr "libswresample" audio resampling, format conversion and mixing
- * @li @subpage libpostproc post processing library
- * @li @subpage libswscale  color conversion and scaling library
+ * @li @ref lpp  "libpostproc" post processing library
+ * @li @ref lsws "libswscale" color conversion and scaling library
  */
 
 /**

libpostproc/postprocess.h

@@ -23,8 +23,13 @@
 
 /**
  * @file
- * @brief
- *     external postprocessing API
+ * @ingroup lpp
+ * external API header
+ */
+
+/**
+ * @defgroup lpp Libpostproc
+ * @{
  */
 
 #include "libpostproc/version.h"
@@ -94,4 +99,8 @@ void pp_free_context(pp_context *ppContext);
 
 #define PP_PICT_TYPE_QP2  0x00000010 ///< MPEG2 style QScale
 
+/**
+ * @}
+ */
+
 #endif /* POSTPROC_POSTPROCESS_H */

libswscale/swscale.h

@@ -23,8 +23,13 @@
 
 /**
  * @file
- * @brief
- *     external api for the swscale stuff
+ * @ingroup lsws
+ * external API header
+ */
+
+/**
+ * @defgroup lsws Libswscale
+ * @{
  */
 
 #include <stdint.h>
@@ -342,4 +347,8 @@ void sws_convertPalette8ToPacked24(const uint8_t *src, uint8_t *dst, int num_pix
  */
 const AVClass *sws_get_class(void);
 
+/**
+ * @}
+ */
+
 #endif /* SWSCALE_SWSCALE_H */