ffmpeg: Allocate (In|Out)putStream.filter_frame early

Based on a commit by Andreas Rheinhardt.

Signed-off-by: James Almer <jamrial@gmail.com>

fftools/ffmpeg.c

@@ -1533,9 +1533,6 @@ static int reap_filters(int flush)
         if (av_buffersink_get_type(filter) == AVMEDIA_TYPE_AUDIO)
             init_output_stream_wrapper(ost, NULL, 1);
 
-        if (!ost->filtered_frame && !(ost->filtered_frame = av_frame_alloc())) {
-            return AVERROR(ENOMEM);
-        }
         filtered_frame = ost->filtered_frame;
 
         while (1) {
@@ -2342,8 +2339,6 @@ static int decode_audio(InputStream *ist, AVPacket *pkt, int *got_output,
 
     if (!ist->decoded_frame && !(ist->decoded_frame = av_frame_alloc()))
         return AVERROR(ENOMEM);
-    if (!ist->filter_frame && !(ist->filter_frame = av_frame_alloc()))
-        return AVERROR(ENOMEM);
     decoded_frame = ist->decoded_frame;
 
     update_benchmark(NULL);
@@ -2415,8 +2410,6 @@ static int decode_video(InputStream *ist, AVPacket *pkt, int *got_output, int64_
 
     if (!ist->decoded_frame && !(ist->decoded_frame = av_frame_alloc()))
         return AVERROR(ENOMEM);
-    if (!ist->filter_frame && !(ist->filter_frame = av_frame_alloc()))
-        return AVERROR(ENOMEM);
     decoded_frame = ist->decoded_frame;
     if (ist->dts != AV_NOPTS_VALUE)
         dts = av_rescale_q(ist->dts, AV_TIME_BASE_Q, ist->st->time_base);

fftools/ffmpeg_opt.c

@@ -889,6 +889,10 @@ static void add_input_streams(OptionsContext *o, AVFormatContext *ic)
             exit_program(1);
         }
 
+        ist->filter_frame = av_frame_alloc();
+        if (!ist->filter_frame)
+            exit_program(1);
+
         ist->pkt = av_packet_alloc();
         if (!ist->pkt)
             exit_program(1);
@@ -1521,6 +1525,10 @@ static OutputStream *new_output_stream(OptionsContext *o, AVFormatContext *oc, e
         exit_program(1);
     }
 
+    ost->filtered_frame = av_frame_alloc();
+    if (!ost->filtered_frame)
+        exit_program(1);
+
     ost->pkt = av_packet_alloc();
     if (!ost->pkt)
         exit_program(1);