HACKING.asciidoc: mention the patch needed for older libav/ffmpeg

libav/ffmpeg 0.8.X series do not have avcodec_encode_video2() which the
code uses, so for these older versions a patch is needed to undo the
changes which added support for that call.

diff --git a/HACKING.asciidoc b/HACKING.asciidoc
index 3c1bc74..a6595fe 100644 (file)
--- a/HACKING.asciidoc
+++ b/HACKING.asciidoc
@@ -19,6 +19,9 @@ On a Debian based system, the dependencies can be installed with this command:
                           libavdevice-dev \
                           libswscale-dev
 
+With libav/ffmpeg version previous than 0.9 this patch is needed:
+http://git.ao2.it/libam7xxx.git/blob_plain/refs/heads/debian:/debian/patches/0002-Revert-am7xxx-play-switch-to-avcodec_encode_video2.patch
+
 The library and the example programs can be compiled following these steps:
 
   $ git clone git://git.ao2.it/libam7xxx.git