avcodec/h264dec: Fix regression with "make fate-h264-attachment-631 THREADS=8"

This treats the case of no slices like no frames which it basically is.

The field is added to the context as other nal related fields are also there
and passing the has_slices field per *arguments is ugly and not consistent

Found-by: ubitux
Approved-by: ubitux
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libavcodec/h264dec.c

@@ -607,6 +607,7 @@ static int decode_nal_units(H264Context *h, const uint8_t *buf, int buf_size)
     int idr_cleared=0;
     int i, ret = 0;
 
+    h->has_slice = 0;
     h->nal_unit_type= 0;
 
     h->max_contexts = h->nb_slice_ctx;
@@ -672,6 +673,7 @@ again:
             h->has_recovery_point = 1;
         case H264_NAL_SLICE:
             sl->gb = nal->gb;
+            h->has_slice = 1;
 
             if ((err = ff_h264_decode_slice_header(h, sl, nal)))
                 break;
@@ -839,7 +841,7 @@ end:
     }
 #endif /* CONFIG_ERROR_RESILIENCE */
     /* clean up */
-    if (h->cur_pic_ptr && !h->droppable) {
+    if (h->cur_pic_ptr && !h->droppable && h->has_slice) {
         ff_thread_report_progress(&h->cur_pic_ptr->tf, INT_MAX,
                                   h->picture_structure == PICT_BOTTOM_FIELD);
     }
@@ -1055,7 +1057,7 @@ static int h264_decode_frame(AVCodecContext *avctx, void *data,
         return send_next_delayed_frame(h, pict, got_frame, buf_index);
     }
 
-    if (!(avctx->flags2 & AV_CODEC_FLAG2_CHUNKS) && !h->cur_pic_ptr) {
+    if (!(avctx->flags2 & AV_CODEC_FLAG2_CHUNKS) && (!h->cur_pic_ptr || !h->has_slice)) {
         if (avctx->skip_frame >= AVDISCARD_NONREF ||
             buf_size >= 4 && !memcmp("Q264", buf, 4))
             return buf_size;

libavcodec/h264dec.h

@@ -446,6 +446,8 @@ typedef struct H264Context {
     int nal_ref_idc;
     int nal_unit_type;
 
+    int has_slice;          ///< slice NAL is found in the packet, set by decode_nal_units, its state does not need to be preserved outside h264_decode_frame()
+
     /**
      * Used to parse AVC variant of H.264
      */

tests/fate/h264.mak

@@ -424,7 +424,7 @@ fate-h264-extreme-plane-pred:                     CMD = framemd5 -i $(TARGET_SAM
 fate-h264-interlace-crop:                         CMD = framecrc -i $(TARGET_SAMPLES)/h264/interlaced_crop.mp4 -vframes 3
 fate-h264-brokensps-2580:                         CMD = framecrc -i $(TARGET_SAMPLES)/h264/brokensps.flv -vf format=yuv420p,scale=w=192:h=144 -sws_flags bitexact+bilinear
 fate-h264-xavc-4389:                              CMD = framecrc -i $(TARGET_SAMPLES)/h264/SonyXAVC_LongGOP_green_pixelation_early_Frames.MXF -pix_fmt yuv422p10le
-fate-h264-attachment-631:                         CMD = framecrc -i $(TARGET_SAMPLES)/h264/attachment631-small.mp4 -an -max_error_rate 0.95
+fate-h264-attachment-631:                         CMD = framecrc -i $(TARGET_SAMPLES)/h264/attachment631-small.mp4 -an -max_error_rate 0.96
 fate-h264-skip-nokey:                             CMD = framecrc -skip_frame nokey -i $(TARGET_SAMPLES)/h264/h264_intra_first-small.ts
 fate-h264-skip-nointra:                           CMD = framecrc -skip_frame nointra -i $(TARGET_SAMPLES)/h264/h264_intra_first-small.ts
 fate-h264-intra-refresh-recovery:                 CMD = framecrc -i $(TARGET_SAMPLES)/h264/intra_refresh.h264 -frames:v 10