From: Daniel Drake <d.drake@mmm.com>

Add ffmpeg configure flag, support both old and new ffmpeg versions correctly

Index: coriander/configure.in
===================================================================
--- coriander.orig/configure.in
+++ coriander/configure.in
@@ -313,42 +315,51 @@ AC_DEFUN([AC_CHECK_LFS],[
 ])
 
 AC_DEFUN([AC_CHECK_FFMPEG],[
+	PKG_CHECK_MODULES(FFMPEG, libavformat libavcodec,
+		have_ffmpeg=yes, have_ffmpeg=no)
 	AC_SUBST(FFMPEG_CFLAGS)
 	AC_SUBST(FFMPEG_LIBS)
-	AC_CHECK_PROG(have_pkg_config, pkg-config --libs libavformat libavcodec, "found", "no")
-	if test x$have_pkg_config = xfound; then 
-	     AC_MSG_CHECKING(ffmpeg version)    
-	     AC_TRY_COMPILE([
-	     #include <ffmpeg/avformat.h>
-	     ],[
-	     int main(void) {
-               AVFormatContext *oc;
-	       AVCodecContext *c;
-               AVStream *st;
-               st = av_new_stream(oc, 0);
-  	       c = st->codec;
-               return 0;
-	     }
-	     ],ffmpeg=ok,ffmpeg=no);
-	     AC_MSG_RESULT($ffmpeg)
- 	     if test x$ffmpeg = xok; then
-	          FFMPEG_LIBS=`pkg-config --libs libavformat libavcodec`
-	          FFMPEG_CFLAGS=`pkg-config --cflags libavformat libavcodec`
-	          AC_DEFINE(HAVE_FFMPEG,1,[defined if ffmpeg is available])
-	     else
-	          AC_MSG_RESULT([ffmpeg required for MPEG video saving.
+
+	# Older ffmpeg releases have ffmpeg-config rather than installing .pc files
+	if test x$have_ffmpeg = xno; then
+		AC_CHECK_PROG(have_ffmpeg, ffmpeg-config, "yes", "no")
+		if test x$have_ffmpeg = xyes; then
+			FFMPEG_LIBS=`ffmpeg-config --libs avformat avcodec`
+			FFMPEG_CFLAGS=`ffmpeg-config --cflags`
+		fi
+	fi
+
+	if test x$have_ffmpeg = xyes; then
+		AC_MSG_CHECKING(ffmpeg version)
+		AC_TRY_COMPILE([#include <ffmpeg/avformat.h>],[
+			int main(void) {
+			AVFormatContext *oc;
+			AVCodecContext *c;
+			AVStream *st;
+			st = av_new_stream(oc, 0);
+			c = st->codec;
+			return 0;
+			}
+			],ffmpeg=ok,ffmpeg=outdated);
+		AC_MSG_RESULT($ffmpeg)
+		if test x$ffmpeg = xok; then
+			AC_DEFINE(HAVE_FFMPEG,1,[defined if ffmpeg is available])
+		else
+			if test "x$want_ffmpeg" = "xyes"; then
+				AC_ERROR([ffmpeg is too old.
 **************************************************************************
-**   ffmpeg can be obtained using your favorite package mamagement      **
-**   system (such as apt-get). Be sure to get ffmpeg and the two        **
-**   development packages libavcodec-dev and libavformat-dev (on        **
-**   Debian). You need version 0.4.9 or later.                          **
-**   Saving JPEG images and MPEG movies is DISABLED.                    **
+**   Please install ffmpeg version 0.4.9 minimum                        **
 **************************************************************************])
-             fi
+			fi
+		fi
 	else
-           AC_MSG_RESULT([pkg_config not found. 
+	  AC_MSG_RESULT([ffmpeg required for MPEG video saving.
 **************************************************************************
-**   This prevents the detection of FFMPEG.                             **
+**   ffmpeg can be obtained using your favorite package mamagement      **
+**   system (such as apt-get). Be sure to get ffmpeg and the two        **
+**   development packages libavcodec-dev and libavformat-dev (on        **
+**   Debian). In the end, you should have the executable 'ffmpeg-config'**
+**   somewhere on your system.                                          **
 **   Saving JPEG images and MPEG movies is DISABLED.                    **
 **************************************************************************])
 	fi
@@ -369,7 +380,14 @@ AC_CHECK_LIBRAW
 AC_CHECK_LIBDC
 AC_CHECK_FTPLIB
 AC_CHECK_SDLLIB
-AC_CHECK_FFMPEG
+
+AC_ARG_ENABLE(ffmpeg,
+	AS_HELP_STRING(--enable-ffmpeg, [enable MPEG video saving (default auto)]),
+	want_ffmpeg=$enableval, want_ffmpeg=auto)
+
+if test "x$want_ffmpeg" != "xno"; then
+	AC_CHECK_FFMPEG
+fi
 
 dnl deprecated:
 dnl AC_CHECK_GDK_PIXBUF