license_plate_recognition/models/yolo.py

import argparse
import logging
import math
import sys
from copy import deepcopy
from pathlib import Path

from models.common import (
    Conv,
    Bottleneck,
    SPP,
    DWConv,
    Focus,
    BottleneckCSP,
    C3,
    ShuffleV2Block,
    Concat,
    NMS,
    autoShape,
    StemBlock,
    BlazeBlock,
    DoubleBlazeBlock,
)
from models.experimental import MixConv2d, CrossConv
from utils.autoanchor import check_anchor_order
from utils.general import make_divisible, check_file, set_logging
from utils.torch_utils import (
    time_synchronized,
    fuse_conv_and_bn,
    model_info,
    scale_img,
    initialize_weights,
    select_device,
    copy_attr,
)

import torch
import torch.nn as nn

sys.path.append("./")  # to run '$ python *.py' files in subdirectories
logger = logging.getLogger(__name__)


try:
    import thop  # for FLOPS computation
except ImportError:
    thop = None


class Detect(nn.Module):
    stride = None  # strides computed during build
    export_cat = False  # onnx export cat output

    def __init__(self, nc=80, anchors=(), ch=()):  # detection layer
        super(Detect, self).__init__()
        self.nc = nc  # number of classes
        # self.no = nc + 5  # number of outputs per anchor
        self.no = nc + 5 + 8  # number of outputs per anchor

        self.nl = len(anchors)  # number of detection layers
        self.na = len(anchors[0]) // 2  # number of anchors
        self.grid = [torch.zeros(1)] * self.nl  # init grid
        a = torch.tensor(anchors).float().view(self.nl, -1, 2)
        self.register_buffer("anchors", a)  # shape(nl,na,2)
        self.register_buffer(
            "anchor_grid", a.clone().view(self.nl, 1, -1, 1, 1, 2)
        )  # shape(nl,1,na,1,1,2)
        self.m = nn.ModuleList(
            nn.Conv2d(x, self.no * self.na, 1) for x in ch
        )  # output conv

    def forward(self, x):
        # x = x.copy()  # for profiling
        z = []  # inference output
        # self.training=True
        if self.export_cat:
            for i in range(self.nl):
                x[i] = self.m[i](x[i])  # conv
                bs, _, ny, nx = x[i].shape  # x(bs,255,20,20) to x(bs,3,20,20,85)
                x[i] = (
                    x[i]
                    .view(bs, self.na, self.no, ny, nx)
                    .permute(0, 1, 3, 4, 2)
                    .contiguous()
                )

                if self.grid[i].shape[2:4] != x[i].shape[2:4]:
                    # self.grid[i] = self._make_grid(nx, ny).to(x[i].device)
                    self.grid[i], self.anchor_grid[i] = self._make_grid_new(nx, ny, i)

                y = torch.full_like(x[i], 0)
                y = y + torch.cat(
                    (
                        x[i][:, :, :, :, 0:5].sigmoid(),
                        torch.cat(
                            (
                                x[i][:, :, :, :, 5:13],
                                x[i][:, :, :, :, 13 : 13 + self.nc].sigmoid(),
                            ),
                            4,
                        ),
                    ),
                    4,
                )

                box_xy = (
                    y[:, :, :, :, 0:2] * 2.0 - 0.5 + self.grid[i].to(x[i].device)
                ) * self.stride[i]  # xy
                box_wh = (y[:, :, :, :, 2:4] * 2) ** 2 * self.anchor_grid[i]  # wh
                # box_conf = torch.cat((box_xy, torch.cat((box_wh, y[:, :, :, :, 4:5]), 4)), 4)

                landm1 = (
                    y[:, :, :, :, 5:7] * self.anchor_grid[i]
                    + self.grid[i].to(x[i].device) * self.stride[i]
                )  # landmark x1 y1
                landm2 = (
                    y[:, :, :, :, 7:9] * self.anchor_grid[i]
                    + self.grid[i].to(x[i].device) * self.stride[i]
                )  # landmark x2 y2
                landm3 = (
                    y[:, :, :, :, 9:11] * self.anchor_grid[i]
                    + self.grid[i].to(x[i].device) * self.stride[i]
                )  # landmark x3 y3
                landm4 = (
                    y[:, :, :, :, 11:13] * self.anchor_grid[i]
                    + self.grid[i].to(x[i].device) * self.stride[i]
                )  # landmark x4 y4
                prob = y[:, :, :, :, 13 : 13 + self.nc]
                score, index_ = torch.max(prob, dim=-1, keepdim=True)
                score = score.type(box_xy.dtype)
                index_ = index_.type(box_xy.dtype)
                index = torch.argmax(prob, dim=-1, keepdim=True).type(box_xy.dtype)
                # landm5 = y[:, :, :, :, 13:13] * self.anchor_grid[i] + self.grid[i].to(x[i].device) * self.stride[i]  # landmark x5 y5
                # landm = torch.cat((landm1, torch.cat((landm2, torch.cat((landm3, torch.cat((landm4, landm5), 4)), 4)), 4)), 4)
                # y = torch.cat((box_conf, torch.cat((landm, y[:, :, :, :, 13:13+self.nc]), 4)), 4)
                y = torch.cat(
                    [
                        box_xy,
                        box_wh,
                        y[:, :, :, :, 4:5],
                        landm1,
                        landm2,
                        landm3,
                        landm4,
                        y[:, :, :, :, 13 : 13 + self.nc],
                    ],
                    -1,
                )

                z.append(y.view(bs, -1, self.no))
            return torch.cat(z, 1)

        for i in range(self.nl):
            x[i] = self.m[i](x[i])  # conv
            bs, _, ny, nx = x[i].shape  # x(bs,255,20,20) to x(bs,3,20,20,85)
            x[i] = (
                x[i]
                .view(bs, self.na, self.no, ny, nx)
                .permute(0, 1, 3, 4, 2)
                .contiguous()
            )

            if not self.training:  # inference
                if self.grid[i].shape[2:4] != x[i].shape[2:4]:
                    self.grid[i] = self._make_grid(nx, ny).to(x[i].device)

                y = torch.full_like(x[i], 0)
                class_range = list(range(5)) + list(range(13, 13 + self.nc))
                y[..., class_range] = x[i][..., class_range].sigmoid()
                y[..., 5:13] = x[i][..., 5:13]
                # y = x[i].sigmoid()

                y[..., 0:2] = (
                    y[..., 0:2] * 2.0 - 0.5 + self.grid[i].to(x[i].device)
                ) * self.stride[i]  # xy
                y[..., 2:4] = (y[..., 2:4] * 2) ** 2 * self.anchor_grid[i]  # wh

                # y[..., 5:13] = y[..., 5:13] * 8 - 4
                y[..., 5:7] = (
                    y[..., 5:7] * self.anchor_grid[i]
                    + self.grid[i].to(x[i].device) * self.stride[i]
                )  # landmark x1 y1
                y[..., 7:9] = (
                    y[..., 7:9] * self.anchor_grid[i]
                    + self.grid[i].to(x[i].device) * self.stride[i]
                )  # landmark x2 y2
                y[..., 9:11] = (
                    y[..., 9:11] * self.anchor_grid[i]
                    + self.grid[i].to(x[i].device) * self.stride[i]
                )  # landmark x3 y3
                y[..., 11:13] = (
                    y[..., 11:13] * self.anchor_grid[i]
                    + self.grid[i].to(x[i].device) * self.stride[i]
                )  # landmark x4 y4
                # y[..., 13:13] = y[..., 13:13] * self.anchor_grid[i] + self.grid[i].to(x[i].device) * self.stride[i]# landmark x5 y5

                # y[..., 5:7] = (y[..., 5:7] * 2 -1) * self.anchor_grid[i]  # landmark x1 y1
                # y[..., 7:9] = (y[..., 7:9] * 2 -1) * self.anchor_grid[i]  # landmark x2 y2
                # y[..., 9:11] = (y[..., 9:11] * 2 -1) * self.anchor_grid[i]  # landmark x3 y3
                # y[..., 11:13] = (y[..., 11:13] * 2 -1) * self.anchor_grid[i]  # landmark x4 y4
                # y[..., 13:13] = (y[..., 13:13] * 2 -1) * self.anchor_grid[i]  # landmark x5 y5

                z.append(y.view(bs, -1, self.no))

        return x if self.training else (torch.cat(z, 1), x)

    @staticmethod
    def _make_grid(nx=20, ny=20):
        yv, xv = torch.meshgrid([torch.arange(ny), torch.arange(nx)] , indexing ='ij')
        return torch.stack((xv, yv), 2).view((1, 1, ny, nx, 2)).float()

    def _make_grid_new(self, nx=20, ny=20, i=0):
        d = self.anchors[i].device
        if (
            "1.10.0" in torch.__version__
        ):  # torch>=1.10.0 meshgrid workaround for torch>=0.7 compatibility
            yv, xv = torch.meshgrid(
                [torch.arange(ny).to(d), torch.arange(nx).to(d)], indexing="ij"
            )
        else:
            yv, xv = torch.meshgrid([torch.arange(ny).to(d), torch.arange(nx).to(d) ] , indexing='ij')
        grid = torch.stack((xv, yv), 2).expand((1, self.na, ny, nx, 2)).float()
        anchor_grid = (
            (self.anchors[i].clone() * self.stride[i])
            .view((1, self.na, 1, 1, 2))
            .expand((1, self.na, ny, nx, 2))
            .float()
        )
        return grid, anchor_grid


class Model(nn.Module):
    def __init__(
        self, cfg="yolov5s.yaml", ch=3, nc=None
    ):  # model, input channels, number of classes
        super(Model, self).__init__()
        if isinstance(cfg, dict):
            self.yaml = cfg  # model dict
        else:  # is *.yaml
            import yaml  # for torch hub

            self.yaml_file = Path(cfg).name
            with open(cfg) as f:
                self.yaml = yaml.load(f, Loader=yaml.FullLoader)  # model dict

        # Define model
        ch = self.yaml["ch"] = self.yaml.get("ch", ch)  # input channels
        if nc and nc != self.yaml["nc"]:
            logger.info(
                "Overriding model.yaml nc=%g with nc=%g" % (self.yaml["nc"], nc)
            )
            self.yaml["nc"] = nc  # override yaml value
        self.model, self.save = parse_model(
            deepcopy(self.yaml), ch=[ch]
        )  # model, savelist
        self.names = [str(i) for i in range(self.yaml["nc"])]  # default names
        # print([x.shape for x in self.forward(torch.zeros(1, ch, 64, 64))])

        # Build strides, anchors
        m = self.model[-1]  # Detect()
        if isinstance(m, Detect):
            s = 128  # 2x min stride
            m.stride = torch.tensor(
                [s / x.shape[-2] for x in self.forward(torch.zeros(1, ch, s, s))]
            )  # forward
            m.anchors /= m.stride.view(-1, 1, 1)
            check_anchor_order(m)
            self.stride = m.stride
            self._initialize_biases()  # only run once
            # print('Strides: %s' % m.stride.tolist())

        # Init weights, biases
        initialize_weights(self)
        self.info()
        logger.info("")

    def forward(self, x, augment=False, profile=False):
        if augment:
            img_size = x.shape[-2:]  # height, width
            s = [1, 0.83, 0.67]  # scales
            f = [None, 3, None]  # flips (2-ud, 3-lr)
            y = []  # outputs
            for si, fi in zip(s, f):
                xi = scale_img(x.flip(fi) if fi else x, si)
                yi = self.forward_once(xi)[0]  # forward
                # cv2.imwrite('img%g.jpg' % s, 255 * xi[0].numpy().transpose((1, 2, 0))[:, :, ::-1])  # save
                yi[..., :4] /= si  # de-scale
                if fi == 2:
                    yi[..., 1] = img_size[0] - yi[..., 1]  # de-flip ud
                elif fi == 3:
                    yi[..., 0] = img_size[1] - yi[..., 0]  # de-flip lr
                y.append(yi)
            return torch.cat(y, 1), None  # augmented inference, train
        else:
            return self.forward_once(x, profile)  # single-scale inference, train

    def forward_once(self, x, profile=False):
        y, dt = [], []  # outputs
        for m in self.model:
            if m.f != -1:  # if not from previous layer
                x = (
                    y[m.f]
                    if isinstance(m.f, int)
                    else [x if j == -1 else y[j] for j in m.f]
                )  # from earlier layers

            if profile:
                o = (
                    thop.profile(m, inputs=(x,), verbose=False)[0] / 1e9 * 2
                    if thop
                    else 0
                )  # FLOPS
                t = time_synchronized()
                for _ in range(10):
                    _ = m(x)
                dt.append((time_synchronized() - t) * 100)
                print("%10.1f%10.0f%10.1fms %-40s" % (o, m.np, dt[-1], m.type))

            x = m(x)  # run
            y.append(x if m.i in self.save else None)  # save output

        if profile:
            print("%.1fms total" % sum(dt))
        return x

    def _initialize_biases(
        self, cf=None
    ):  # initialize biases into Detect(), cf is class frequency
        # https://arxiv.org/abs/1708.02002 section 3.3
        # cf = torch.bincount(torch.tensor(np.concatenate(dataset.labels, 0)[:, 0]).long(), minlength=nc) + 1.
        m = self.model[-1]  # Detect() module
        for mi, s in zip(m.m, m.stride):  # from
            b = mi.bias.view(m.na, -1)  # conv.bias(255) to (3,85)
            b.data[:, 4] += math.log(
                8 / (640 / s) ** 2
            )  # obj (8 objects per 640 image)
            b.data[:, 5:] += (
                math.log(0.6 / (m.nc - 0.99))
                if cf is None
                else torch.log(cf / cf.sum())
            )  # cls
            mi.bias = torch.nn.Parameter(b.view(-1), requires_grad=True)

    def _print_biases(self):
        m = self.model[-1]  # Detect() module
        for mi in m.m:  # from
            b = mi.bias.detach().view(m.na, -1).T  # conv.bias(255) to (3,85)
            print(
                ("%6g Conv2d.bias:" + "%10.3g" * 6)
                % (mi.weight.shape[1], *b[:5].mean(1).tolist(), b[5:].mean())
            )

    # def _print_weights(self):
    #     for m in self.model.modules():
    #         if type(m) is Bottleneck:
    #             print('%10.3g' % (m.w.detach().sigmoid() * 2))  # shortcut weights

    def fuse(self):  # fuse model Conv2d() + BatchNorm2d() layers
        print("Fusing layers... ")
        for m in self.model.modules():
            if type(m) is Conv and hasattr(m, "bn"):
                m.conv = fuse_conv_and_bn(m.conv, m.bn)  # update conv
                delattr(m, "bn")  # remove batchnorm
                m.forward = m.fuseforward  # update forward
            elif type(m) is nn.Upsample:
                m.recompute_scale_factor = None  # torch 1.11.0 compatibility
        self.info()
        return self

    def nms(self, mode=True):  # add or remove NMS module
        present = type(self.model[-1]) is NMS  # last layer is NMS
        if mode and not present:
            print("Adding NMS... ")
            m = NMS()  # module
            m.f = -1  # from
            m.i = self.model[-1].i + 1  # index
            self.model.add_module(name="%s" % m.i, module=m)  # add
            self.eval()
        elif not mode and present:
            print("Removing NMS... ")
            self.model = self.model[:-1]  # remove
        return self

    def autoshape(self):  # add autoShape module
        print("Adding autoShape... ")
        m = autoShape(self)  # wrap model
        copy_attr(
            m, self, include=("yaml", "nc", "hyp", "names", "stride"), exclude=()
        )  # copy attributes
        return m

    def info(self, verbose=False, img_size=640):  # print model information
        model_info(self, verbose, img_size)


def parse_model(d, ch):  # model_dict, input_channels(3)
    logger.info(
        "\n%3s%18s%3s%10s  %-40s%-30s"
        % ("", "from", "n", "params", "module", "arguments")
    )
    anchors, nc, gd, gw = (
        d["anchors"],
        d["nc"],
        d["depth_multiple"],
        d["width_multiple"],
    )
    na = (
        (len(anchors[0]) // 2) if isinstance(anchors, list) else anchors
    )  # number of anchors
    no = na * (nc + 5)  # number of outputs = anchors * (classes + 5)

    layers, save, c2 = [], [], ch[-1]  # layers, savelist, ch out
    for i, (f, n, m, args) in enumerate(
        d["backbone"] + d["head"]
    ):  # from, number, module, args
        m = eval(m) if isinstance(m, str) else m  # eval strings
        for j, a in enumerate(args):
            try:
                args[j] = eval(a) if isinstance(a, str) else a  # eval strings
            except:
                pass

        n = max(round(n * gd), 1) if n > 1 else n  # depth gain
        if m in [
            Conv,
            Bottleneck,
            SPP,
            DWConv,
            MixConv2d,
            Focus,
            CrossConv,
            BottleneckCSP,
            C3,
            ShuffleV2Block,
            StemBlock,
            BlazeBlock,
            DoubleBlazeBlock,
        ]:
            c1, c2 = ch[f], args[0]

            # Normal
            # if i > 0 and args[0] != no:  # channel expansion factor
            #     ex = 1.75  # exponential (default 2.0)
            #     e = math.log(c2 / ch[1]) / math.log(2)
            #     c2 = int(ch[1] * ex ** e)
            # if m != Focus:

            c2 = make_divisible(c2 * gw, 8) if c2 != no else c2

            # Experimental
            # if i > 0 and args[0] != no:  # channel expansion factor
            #     ex = 1 + gw  # exponential (default 2.0)
            #     ch1 = 32  # ch[1]
            #     e = math.log(c2 / ch1) / math.log(2)  # level 1-n
            #     c2 = int(ch1 * ex ** e)
            # if m != Focus:
            #     c2 = make_divisible(c2, 8) if c2 != no else c2

            args = [c1, c2, *args[1:]]
            if m in [BottleneckCSP, C3]:
                args.insert(2, n)
                n = 1
        elif m is nn.BatchNorm2d:
            args = [ch[f]]
        elif m is Concat:
            c2 = sum([ch[-1 if x == -1 else x + 1] for x in f])
        elif m is Detect:
            args.append([ch[x + 1] for x in f])
            if isinstance(args[1], int):  # number of anchors
                args[1] = [list(range(args[1] * 2))] * len(f)
        else:
            c2 = ch[f]

        m_ = (
            nn.Sequential(*[m(*args) for _ in range(n)]) if n > 1 else m(*args)
        )  # module
        t = str(m)[8:-2].replace("__main__.", "")  # module type
        np = sum([x.numel() for x in m_.parameters()])  # number params
        m_.i, m_.f, m_.type, m_.np = (
            i,
            f,
            t,
            np,
        )  # attach index, 'from' index, type, number params
        logger.info("%3s%18s%3s%10.0f  %-40s%-30s" % (i, f, n, np, t, args))  # print
        save.extend(
            x % i for x in ([f] if isinstance(f, int) else f) if x != -1
        )  # append to savelist
        layers.append(m_)
        ch.append(c2)
    return nn.Sequential(*layers), sorted(save)


from thop import profile
from thop import clever_format

if __name__ == "__main__":
    parser = argparse.ArgumentParser()
    parser.add_argument("--cfg", type=str, default="yolov5s.yaml", help="model.yaml")
    parser.add_argument(
        "--device", default="", help="cuda device, i.e. 0 or 0,1,2,3 or cpu"
    )
    opt = parser.parse_args()
    opt.cfg = check_file(opt.cfg)  # check file
    set_logging()
    device = select_device(opt.device)

    # Create model
    model = Model(opt.cfg).to(device)
    stride = model.stride.max()
    if stride == 32:
        input = torch.Tensor(1, 3, 480, 640).to(device)
    else:
        input = torch.Tensor(1, 3, 512, 640).to(device)
    model.train()
    print(model)
    flops, params = profile(model, inputs=(input, ))
    flops, params = clever_format([flops, params], "%.3f")
    print('Flops:', flops, ',Params:' ,params)