Potential error in sample app (deepstream-image-meta-test)

[hyperlight]

Please provide complete information as applicable to your setup.

• DeepStream Version:5.1
• TensorRT Version:7.2
• NVIDIA GPU Driver Version (valid for GPU only):470
• Issue Type( questions, new requirements, bugs):bugs

From deepstream-5.1/sources/apps/sample_apps/deepstream-image-meta-test/deepstream_image_meta_test.c

static GstPadProbeReturn
pgie_src_pad_buffer_probe (GstPad * pad, GstPadProbeInfo * info, gpointer ctx)
{
  GstBuffer *buf = (GstBuffer *) info->data;
  GstMapInfo inmap = GST_MAP_INFO_INIT;
  if (!gst_buffer_map (buf, &inmap, GST_MAP_READ)) {
    GST_ERROR ("input buffer mapinfo failed");
    return GST_FLOW_ERROR; // <---- INCORRECT RETURN TYPE
  }
  NvBufSurface *ip_surf = (NvBufSurface *) inmap.data;
  gst_buffer_unmap (buf, &inmap);

  NvDsObjectMeta *obj_meta = NULL;
  guint vehicle_count = 0;
  guint person_count = 0;
  NvDsMetaList *l_frame = NULL;
  NvDsMetaList *l_obj = NULL;
  NvDsBatchMeta *batch_meta = gst_buffer_get_nvds_batch_meta (buf);

  for (l_frame = batch_meta->frame_meta_list; l_frame != NULL;
      l_frame = l_frame->next) {
    NvDsFrameMeta *frame_meta = (NvDsFrameMeta *) (l_frame->data);
    guint num_rects = 0;
    for (l_obj = frame_meta->obj_meta_list; l_obj != NULL; l_obj = l_obj->next) {
      obj_meta = (NvDsObjectMeta *) (l_obj->data);
      if (obj_meta->class_id == PGIE_CLASS_ID_VEHICLE) {
        vehicle_count++;
        num_rects++;
      }
      if (obj_meta->class_id == PGIE_CLASS_ID_PERSON) {
        person_count++;
        num_rects++;
      }
      /* Conditions that user needs to set to encode the detected objects of
       * interest. Here, by default all the detected objects are encoded.
       * For demonstration, we will encode the first object in the frame */
      if ((obj_meta->class_id == PGIE_CLASS_ID_PERSON
              || obj_meta->class_id == PGIE_CLASS_ID_VEHICLE)
          && num_rects == 1) {
        NvDsObjEncUsrArgs userData = { 0 };
        /* To be set by user */
        userData.saveImg = save_img;
        userData.attachUsrMeta = attach_user_meta;
        /* Set if Image scaling Required */
        userData.scaleImg = FALSE;
        userData.scaledWidth = 0;
        userData.scaledHeight = 0;
        /* Preset */
        userData.objNum = num_rects;
        /*Main Function Call */
        nvds_obj_enc_process (ctx, &userData, ip_surf, obj_meta, frame_meta);
      }
    }
  }
  nvds_obj_enc_finish (ctx);
  return GST_PAD_PROBE_OK;
}

The returned value on error is GST_FLOW_ERROR which is not among the valid return values of type GstPadProbeReturn

typedef enum
{
  GST_PAD_PROBE_DROP,
  GST_PAD_PROBE_OK,
  GST_PAD_PROBE_REMOVE,
  GST_PAD_PROBE_PASS,
  GST_PAD_PROBE_HANDLED
} GstPadProbeReturn;

I think instead of GST_FLOW_ERROR, the function should return GST_PAD_PROBE_OK on error to skip this probe?

[yuweiw]

Hi @hyperlight . Yes, you are right. The fucntion should return GST_PAD_PROBE_DROP. GST_FLOW_ERROR is the valid value for GstFlowReturn structure. We will fix it in future releases(after 6.1). Also, since it’s an open source code part, you can change it in your env when you use it. Thanks