Testing av_detection_bbox_alloc()
alloc 0: OK, nb=0, size>0=yes
alloc 1: OK, nb=1, size>0=yes
alloc 4: OK, nb=4, size>0=yes
alloc (no size): OK

Testing av_get_detection_bbox()
bbox 0: x=0 y=0 w=50 h=60 label=obj0 conf=90/100
bbox 1: x=100 y=200 w=51 h=61 label=obj1 conf=91/100
bbox 2: x=200 y=400 w=52 h=62 label=obj2 conf=92/100

Testing classify fields
classify_count=2
classify 0: cat 95/100
classify 1: animal 80/100

Testing source field
source: test_model_v1

Testing av_detection_bbox_create_side_data()
side_data: OK, nb=2
side_data bbox 0: x=10 y=20
