[FFmpeg-cvslog] Revert "avcodec/mediacodecdec: wait on first frame after input buffers are full"

[Aman Gupta]

ffmpeg | branch: release/4.0 | Aman Gupta <aman at tmm1.net> | Mon Jun 18 11:53:27 2018 -0700| [789bac72ededafca789eeca86f106f43dcc6ab2c] | committer: Aman Gupta

Revert "avcodec/mediacodecdec: wait on first frame after input buffers are full"

@xyz reported a regression on his Sony Xperia Z3 Tablet Compact where
playback would intermittently fail to start, essentially deadlocking in
the decoder. Bisecting narrowed down the issue to this commit, which was
meant as an optimization but is not necessary.

This reverts commit a75bb5496ac6e7e194f1c6fd3b87f02a52e74adb.

Signed-off-by: Aman Gupta <aman at tmm1.net>
(cherry picked from commit 37c2cb6a68a4cbd746b0a56e38f28f7ee84e925f)

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=789bac72ededafca789eeca86f106f43dcc6ab2c
---

 libavcodec/mediacodecdec_common.c | 8 +++++++-
 libavcodec/mediacodecdec_common.h | 1 +
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/libavcodec/mediacodecdec_common.c b/libavcodec/mediacodecdec_common.c
index 40a2ee6778..887865a281 100644
--- a/libavcodec/mediacodecdec_common.c
+++ b/libavcodec/mediacodecdec_common.c
@@ -443,6 +443,8 @@ static int mediacodec_dec_flush_codec(AVCodecContext *avctx, MediaCodecDecContex
     FFAMediaCodec *codec = s->codec;
     int status;
 
+    s->output_buffer_count = 0;
+
     s->draining = 0;
     s->flushing = 0;
     s->eos = 0;
@@ -670,7 +672,10 @@ int ff_mediacodec_dec_receive(AVCodecContext *avctx, MediaCodecDecContext *s,
         /* If the codec is flushing or need to be flushed, block for a fair
          * amount of time to ensure we got a frame */
         output_dequeue_timeout_us = OUTPUT_DEQUEUE_BLOCK_TIMEOUT_US;
-    } else if (!wait) {
+    } else if (s->output_buffer_count == 0 || !wait) {
+        /* If the codec hasn't produced any frames, do not block so we
+         * can push data to it as fast as possible, and get the first
+         * frame */
         output_dequeue_timeout_us = 0;
     }
 
@@ -704,6 +709,7 @@ int ff_mediacodec_dec_receive(AVCodecContext *avctx, MediaCodecDecContext *s,
                 }
             }
 
+            s->output_buffer_count++;
             return 0;
         } else {
             status = ff_AMediaCodec_releaseOutputBuffer(codec, index, 0);
diff --git a/libavcodec/mediacodecdec_common.h b/libavcodec/mediacodecdec_common.h
index d280236b8e..0b21129fee 100644
--- a/libavcodec/mediacodecdec_common.h
+++ b/libavcodec/mediacodecdec_common.h
@@ -64,6 +64,7 @@ typedef struct MediaCodecDecContext {
     int display_width;
     int display_height;
 
+    uint64_t output_buffer_count;
     ssize_t current_input_buffer;
 
     bool delay_flush;