From 137707e53a29131ae6ed5a2ecb8960cbf1d6284a Mon Sep 17 00:00:00 2001 From: Justin Ruggles Date: Tue, 17 Mar 2009 01:43:01 +0000 Subject: [PATCH] Add documentation about missing E-AC-3 features. Originally committed as revision 18021 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavcodec/eac3dec.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/libavcodec/eac3dec.c b/libavcodec/eac3dec.c index f57c1cc617..8af729dc22 100644 --- a/libavcodec/eac3dec.c +++ b/libavcodec/eac3dec.c @@ -20,6 +20,34 @@ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ +/* + * There are several features of E-AC-3 that this decoder does not yet support. + * + * Spectral Extension + * There is a patch to get this working for the two samples we have that + * use it, but it needs some minor changes in order to be accepted. + * + * Enhanced Coupling + * No known samples exist. If any ever surface, this feature should not be + * too difficult to implement. + * + * Reduced Sample Rates + * No known samples exist. The spec also does not give clear information + * on how this is to be implemented. + * + * Dependent Streams + * Only the independent stream is currently decoded. Any dependent + * streams are skipped. We have only come across two examples of this, and + * they are both just test streams, one for HD-DVD and the other for + * Blu-ray. + * + * Transient Pre-noise Processing + * This is side information which a decoder should use to reduce artifacts + * caused by transients. There are samples which are known to have this + * information, but this decoder currently ignores it. + */ + + #include "avcodec.h" #include "internal.h" #include "aac_ac3_parser.h"