libavcodec/libx264: add a flag to output ROI warnings only once.

Signed-off-by: Guo, Yejun <yejun.guo@intel.com>

libavcodec/libx264.c

@@ -99,6 +99,12 @@ typedef struct X264Context {
 
     int nb_reordered_opaque, next_reordered_opaque;
     int64_t *reordered_opaque;
+
+    /**
+     * If the encoder does not support ROI then warn the first time we
+     * encounter a frame with ROI side data.
+     */
+    int roi_warned;
 } X264Context;
 
 static void X264_log(void *p, int level, const char *fmt, va_list args)
@@ -356,7 +362,10 @@ static int X264_frame(AVCodecContext *ctx, AVPacket *pkt, const AVFrame *frame,
         sd = av_frame_get_side_data(frame, AV_FRAME_DATA_REGIONS_OF_INTEREST);
         if (sd) {
             if (x4->params.rc.i_aq_mode == X264_AQ_NONE) {
+                if (!x4->roi_warned) {
+                    x4->roi_warned = 1;
                     av_log(ctx, AV_LOG_WARNING, "Adaptive quantization must be enabled to use ROI encoding, skipping ROI.\n");
+                }
             } else {
                 if (frame->interlaced_frame == 0) {
                     int mbx = (frame->width + MB_SIZE - 1) / MB_SIZE;
@@ -410,11 +419,14 @@ static int X264_frame(AVCodecContext *ctx, AVPacket *pkt, const AVFrame *frame,
                     x4->pic.prop.quant_offsets = qoffsets;
                     x4->pic.prop.quant_offsets_free = av_free;
                 } else {
+                    if (!x4->roi_warned) {
+                        x4->roi_warned = 1;
                         av_log(ctx, AV_LOG_WARNING, "interlaced_frame not supported for ROI encoding yet, skipping ROI.\n");
                     }
                 }
             }
         }
+    }
 
     do {
         if (x264_encoder_encode(x4->enc, &nal, &nnal, frame? &x4->pic: NULL, &pic_out) < 0)