[FFmpeg-devel] [PATCH 2/3] libavcodec/qsvdec: remove redundant decodeHeader()

[wenbin.chen at intel.com]

From: "Chen,Wenbin" <wenbin.chen at intel.com>

Since ffmpeg-qsv uses return value to reinit decoder, it doesn't need to
decode header each time. Move qsv_decode_header's position so that
it will be called only if codec needed to be reinitialized.
Rearrange the code of flushing decoder and re-init decoder operation.
Remove the buffer_count and use the got_frame to decide whether the
decoder is drain.

Signed-off-by: Wenbin Chen <wenbin.chen at intel.com>
Signed-off-by Guangxin Xu <guangxin.xu at intel.com>
---
 libavcodec/qsvdec.c | 26 ++++++++++++--------------
 1 file changed, 12 insertions(+), 14 deletions(-)

diff --git a/libavcodec/qsvdec.c b/libavcodec/qsvdec.c
index 88232f5d8d..fe416e74ca 100644
--- a/libavcodec/qsvdec.c
+++ b/libavcodec/qsvdec.c
@@ -63,7 +63,6 @@ typedef struct QSVContext {
 
     AVFifoBuffer *async_fifo;
     int zero_consume_run;
-    int buffered_count;
     int reinit_flag;
 
     enum AVPixelFormat orig_pix_fmt;
@@ -504,8 +503,6 @@ static int qsv_decode(AVCodecContext *avctx, QSVContext *q,
         ++q->zero_consume_run;
         if (q->zero_consume_run > 1)
             ff_qsv_print_warning(avctx, ret, "A decode call did not consume any data");
-    } else if (!*sync && bs.DataOffset) {
-        ++q->buffered_count;
     } else {
         q->zero_consume_run = 0;
     }
@@ -637,20 +634,21 @@ static int qsv_process_data(AVCodecContext *avctx, QSVContext *q,
     if (!avctx->coded_height)
         avctx->coded_height = 720;
 
-    ret = qsv_decode_header(avctx, q, pkt, pix_fmt, &param);
-
-    if (q->reinit_flag || (ret >= 0 && (q->orig_pix_fmt != ff_qsv_map_fourcc(param.mfx.FrameInfo.FourCC) ||
-        avctx->coded_width  != param.mfx.FrameInfo.Width ||
-        avctx->coded_height != param.mfx.FrameInfo.Height))) {
+    /* decode zero-size pkt to flush the buffered pkt before reinit */
+    if (q->reinit_flag) {
         AVPacket zero_pkt = {0};
+        ret = qsv_decode(avctx, q, frame, got_frame, &zero_pkt);
+        if (*got_frame)
+            return ret;
+    }
 
-        if (q->buffered_count) {
-            q->reinit_flag = 1;
-            /* decode zero-size pkt to flush the buffered pkt before reinit */
-            q->buffered_count--;
-            return qsv_decode(avctx, q, frame, got_frame, &zero_pkt);
-        }
+    if (q->reinit_flag || !q->session) {
         q->reinit_flag = 0;
+        ret = qsv_decode_header(avctx, q, pkt, pix_fmt, &param);
+        if (ret < 0) {
+            av_log(avctx, AV_LOG_ERROR, "Error decoding header\n");
+            goto reinit_fail;
+        }
 
         q->orig_pix_fmt = avctx->pix_fmt = pix_fmt = ff_qsv_map_fourcc(param.mfx.FrameInfo.FourCC);
 
-- 
2.25.1