doc/examples/filtering_video: switch to new decoding API

doc/examples/filtering_video.c

@@ -213,7 +213,6 @@ int main(int argc, char **argv)
     AVPacket packet;
     AVFrame *frame = av_frame_alloc();
     AVFrame *filt_frame = av_frame_alloc();
-    int got_frame;
 
     if (!frame || !filt_frame) {
         perror("Could not allocate frame");
@@ -238,14 +237,22 @@ int main(int argc, char **argv)
             break;
 
         if (packet.stream_index == video_stream_index) {
-            got_frame = 0;
-            ret = avcodec_decode_video2(dec_ctx, frame, &got_frame, &packet);
+            ret = avcodec_send_packet(dec_ctx, &packet);
             if (ret < 0) {
-                av_log(NULL, AV_LOG_ERROR, "Error decoding video\n");
+                av_log(NULL, AV_LOG_ERROR, "Error while sending a packet to the decoder\n");
                 break;
             }
 
-            if (got_frame) {
+            while (ret >= 0) {
+                ret = avcodec_receive_frame(dec_ctx, frame);
+                if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
+                    break;
+                } else if (ret < 0) {
+                    av_log(NULL, AV_LOG_ERROR, "Error while receiving a frame from the decoder\n");
+                    goto end;
+                }
+
+                if (ret >= 0) {
                     frame->pts = av_frame_get_best_effort_timestamp(frame);
 
                     /* push the decoded frame into the filtergraph */
@@ -267,6 +274,7 @@ int main(int argc, char **argv)
                     av_frame_unref(frame);
                 }
             }
+        }
         av_packet_unref(&packet);
     }
 end: