Backport of [21787]: Get human readible string from a vlc_fourcc_t.

include/vlc_common.h

@@ -3,7 +3,7 @@
  * Collection of useful common types and macros definitions
  *****************************************************************************
  * Copyright (C) 1998-2005 the VideoLAN team
- * $Id$
+ * $Id: 47038af022b63418ff42884b90a010117fe49204 $
  *
  * Authors: Samuel Hocevar <sam@via.ecp.fr>
  *          Vincent Seguin <seguin@via.ecp.fr>
@@ -193,6 +193,24 @@ typedef uint32_t vlc_fourcc_t;
 
 #endif
 
+static inline void __vlc_fourcc_to_char( vlc_fourcc_t fcc, char *psz_fourcc )
+{
+#ifdef WORDS_BIGENDIAN
+    psz_fourcc[0] = (uint32_t) (fcc >> 24);
+    psz_fourcc[1] = (uint32_t) (fcc >> 16);
+    psz_fourcc[2] = (uint32_t) (fcc >> 8);
+    psz_fourcc[3] = (uint32_t) (fcc);
+#else
+    psz_fourcc[3] = (uint32_t) (fcc >> 24);
+    psz_fourcc[2] = (uint32_t) (fcc >> 16);
+    psz_fourcc[1] = (uint32_t) (fcc >> 8);
+    psz_fourcc[0] = (uint32_t) (fcc);
+#endif
+}
+
+#define vlc_fourcc_to_char( a, b ) \
+    __vlc_fourcc_to_char( (vlc_fourcc_t)(a), (char *)(b) )
+
 /*****************************************************************************
  * Classes declaration
  *****************************************************************************/

modules/codec/dvbsub.c

@@ -1790,7 +1790,10 @@ static block_t *Encode( encoder_t *p_enc, subpicture_t *p_subpic )
     if( p_region->fmt.i_chroma != VLC_FOURCC('T','E','X','T') &&
         p_region->fmt.i_chroma != VLC_FOURCC('Y','U','V','P') )
     {
-        msg_Err( p_enc, "chroma not supported" );
+        char *psz_fourcc[5];
+        memset( &psz_fourcc, 0, 5);
+        vlc_fourcc_to_char( p_region->fmt.i_chroma, &psz_fourcc );
+        msg_Err( p_enc, "chroma %4s not supported", &psz_fourcc );
         return NULL;
     }