license-plate-recognition-barrier-0001

Use Case and High-Level Description

This model uses a small-footprint network trained end-to-end to recognize Chinese license plates in traffic.

Validation Dataset - Internal

1165 Chinese plates from different provinces

Example

Note: The license plates on the image were modified to protect the owners’ privacy.

Specification

Metric

Value

Rotation in-plane

±10˚

Rotation out-of-plane

Yaw: ±45˚ / Pitch: ±45˚

Min plate width

94 pixels

Ratio of correct reads

88.58%

GFlops

0.328

MParams

1.218

Source framework

Caffe*

Limitations

Only “blue” license plates, which are common in public, were tested thoroughly. Other types of license plates may underperform.

Inputs

  1. Image, name: data, shape: 1, 3, 24, 94 in the format 1, C, H, W, where:

    • C - number of channels

    • H - image height

    • W - image width

    Expected color order is BGR.

  2. An auxiliary blob that is needed for correct decoding, name: seq_ind, shape: 88,1. Set this to [1, 1, 1, ..., 1].

Outputs

Encoded vector of floats, name: dec, shape: 1, 88, 1, 1. Each float is an integer number encoding a character according to this dictionary:

    0 0
    1 1
    2 2
    3 3
    4 4
    5 5
    6 6
    7 7
    8 8
    9 9
    10 <Anhui>
    11 <Beijing>
    12 <Chongqing>
    13 <Fujian>
    14 <Gansu>
    15 <Guangdong>
    16 <Guangxi>
    17 <Guizhou>
    18 <Hainan>
    19 <Hebei>
    20 <Heilongjiang>
    21 <Henan>
    22 <HongKong>
    23 <Hubei>
    24 <Hunan>
    25 <InnerMongolia>
    26 <Jiangsu>
    27 <Jiangxi>
    28 <Jilin>
    29 <Liaoning>
    30 <Macau>
    31 <Ningxia>
    32 <Qinghai>
    33 <Shaanxi>
    34 <Shandong>
    35 <Shanghai>
    36 <Shanxi>
    37 <Sichuan>
    38 <Tianjin>
    39 <Tibet>
    40 <Xinjiang>
    41 <Yunnan>
    42 <Zhejiang>
    43 <police>
    44 A
    45 B
    46 C
    47 D
    48 E
    49 F
    50 G
    51 H
    52 I
    53 J
    54 K
    55 L
    56 M
    57 N
    58 O
    59 P
    60 Q
    61 R
    62 S
    63 T
    64 U
    65 V
    66 W
    67 X
    68 Y
    69 Z

Demo usage

The model can be used in the following demos provided by the Open Model Zoo to show its capabilities: