[FFmpeg-devel] [PATCH 3/4] fftools/ffmpeg: support variable dimension encode

[Linjie Fu]

Flush encoders when dimension change happens, reset draining to resume
encode.

If encoder doesn't support variable dimension, stop encoding and
report errors.

Signed-off-by: Linjie Fu <linjie.fu at intel.com>
---
 fftools/ffmpeg.c    | 13 +++++++++++++
 libavcodec/encode.c |  4 ++++
 2 files changed, 17 insertions(+)

diff --git a/fftools/ffmpeg.c b/fftools/ffmpeg.c
index 5d52430..8ceeaaa 100644
--- a/fftools/ffmpeg.c
+++ b/fftools/ffmpeg.c
@@ -130,6 +130,7 @@ static void do_video_stats(OutputStream *ost, int frame_size);
 static BenchmarkTimeStamps get_benchmark_time_stamps(void);
 static int64_t getmaxrss(void);
 static int ifilter_has_all_input_formats(FilterGraph *fg);
+static void flush_encoders(void);
 
 static int run_as_daemon  = 0;
 static int nb_frames_dup = 0;
@@ -1067,6 +1068,18 @@ static void do_video_out(OutputFile *of,
     InputStream *ist = NULL;
     AVFilterContext *filter = ost->filter->filter;
 
+    /* flush encoders in dynamic resolution encode */
+    if (next_picture && (enc->width != next_picture->width ||
+                         enc->height != next_picture->height)) {
+        flush_encoders();
+
+        if (!(enc->codec->capabilities & AV_CODEC_CAP_VARIABLE_DIMENSIONS)) {
+            av_log(NULL, AV_LOG_ERROR, "Dynamic resolution encode "
+                            "is not supported by %s.\n", enc->codec->name);
+            goto error;
+        }
+    }
+
     if (ost->source_index >= 0)
         ist = input_streams[ost->source_index];
 
diff --git a/libavcodec/encode.c b/libavcodec/encode.c
index d12c425..9303bc9 100644
--- a/libavcodec/encode.c
+++ b/libavcodec/encode.c
@@ -389,6 +389,10 @@ int attribute_align_arg avcodec_send_frame(AVCodecContext *avctx, const AVFrame
     if (!avcodec_is_open(avctx) || !av_codec_is_encoder(avctx->codec))
         return AVERROR(EINVAL);
 
+    /* reset draining when encoder is flushed in variable dimensions encoding */
+    if (frame)
+        avctx->internal->draining = 0;
+
     if (avctx->internal->draining)
         return AVERROR_EOF;
 
-- 
2.7.4