[FFmpeg-cvslog] lavc/h264_slice: clarify informational message in case of disabled slice multi-threaded decoding

Stefano Sabatini git at videolan.org
Fri Jun 20 12:23:25 CEST 2014


ffmpeg | branch: master | Stefano Sabatini <stefasab at gmail.com> | Mon Jun  9 19:32:37 2014 +0200| [d381109ce8acd84fc16d3dfc4f8f688462d45366] | committer: Stefano Sabatini

lavc/h264_slice: clarify informational message in case of disabled slice multi-threaded decoding

Also suggest what can be done to workaround the limitation.

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=d381109ce8acd84fc16d3dfc4f8f688462d45366
---

 libavcodec/h264_slice.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/libavcodec/h264_slice.c b/libavcodec/h264_slice.c
index a0288e0..e6645e8 100644
--- a/libavcodec/h264_slice.c
+++ b/libavcodec/h264_slice.c
@@ -1884,7 +1884,10 @@ int ff_h264_decode_slice_header(H264Context *h, H264Context *h0)
             h0->max_contexts = 1;
             if (!h0->single_decode_warning) {
                 av_log(h->avctx, AV_LOG_INFO,
-                       "Cannot parallelize deblocking type 1, decoding such frames in sequential order\n");
+                       "Cannot parallelize slice decoding with deblocking filter type 1, decoding such frames in sequential order\n"
+                       "To parallelize slice decoding you need video encoded with disable_deblocking_filter_idc set to 2 (deblock only edges that do not cross slices).\n"
+                       "Setting the flags2 libavcodec option to +fast (-flags2 +fast) will disable deblocking across slices and enable parallel slice decoding "
+                       "but will generate non-standard-compliant output.\n");
                 h0->single_decode_warning = 1;
             }
             if (h != h0) {



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