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svod_model/blocks/
bottleneck.rs

1use snafu::ResultExt;
2use svod_tensor::Tensor;
3
4use crate::state::{self, HasStateDict, StateDict, prefixed};
5
6use super::basic_block::BlockKind;
7use super::batchnorm::BatchNormWeights;
8use super::conv::Conv2dWeights;
9use super::error::{Result, TensorSnafu};
10
11#[derive(Clone)]
12pub struct Bottleneck {
13    pub conv1: Conv2dWeights,
14    pub bn1: BatchNormWeights,
15    pub conv2: Conv2dWeights,
16    pub bn2: BatchNormWeights,
17    pub conv3: Conv2dWeights,
18    pub bn3: BatchNormWeights,
19    pub downsample: Option<(Conv2dWeights, BatchNormWeights)>,
20}
21
22impl Bottleneck {
23    pub fn empty(in_planes: usize, planes: usize, stride: usize) -> Self {
24        let expansion = BlockKind::Bottleneck.expansion();
25        let out_ch = planes * expansion;
26        let downsample = if stride != 1 || in_planes != out_ch {
27            Some((Conv2dWeights::empty(out_ch, in_planes, 1, stride, 0), BatchNormWeights::empty(out_ch)))
28        } else {
29            None
30        };
31        Self {
32            conv1: Conv2dWeights::empty(planes, in_planes, 1, 1, 0),
33            bn1: BatchNormWeights::empty(planes),
34            conv2: Conv2dWeights::empty(planes, planes, 3, stride, 1),
35            bn2: BatchNormWeights::empty(planes),
36            conv3: Conv2dWeights::empty(out_ch, planes, 1, 1, 0),
37            bn3: BatchNormWeights::empty(out_ch),
38            downsample,
39        }
40    }
41
42    pub fn forward(&self, x: &Tensor) -> Result<Tensor> {
43        let out = self.bn1.forward(&self.conv1.forward(x)?)?.relu().context(TensorSnafu)?;
44        let out = self.bn2.forward(&self.conv2.forward(&out)?)?.relu().context(TensorSnafu)?;
45        let out = self.bn3.forward(&self.conv3.forward(&out)?)?;
46        let shortcut = match &self.downsample {
47            Some((c, b)) => b.forward(&c.forward(x)?)?,
48            None => x.clone(),
49        };
50        out.try_add(&shortcut).context(TensorSnafu)?.relu().context(TensorSnafu)
51    }
52}
53
54impl HasStateDict for Bottleneck {
55    fn state_dict(&self, prefix: &str) -> StateDict {
56        let mut sd = self.conv1.state_dict(&prefixed(prefix, "conv1"));
57        sd.extend(self.bn1.state_dict(&prefixed(prefix, "bn1")));
58        sd.extend(self.conv2.state_dict(&prefixed(prefix, "conv2")));
59        sd.extend(self.bn2.state_dict(&prefixed(prefix, "bn2")));
60        sd.extend(self.conv3.state_dict(&prefixed(prefix, "conv3")));
61        sd.extend(self.bn3.state_dict(&prefixed(prefix, "bn3")));
62        if let Some((c, b)) = &self.downsample {
63            sd.extend(c.state_dict(&prefixed(prefix, "downsample.0")));
64            sd.extend(b.state_dict(&prefixed(prefix, "downsample.1")));
65        }
66        sd
67    }
68
69    fn load_state_dict(&mut self, sd: &StateDict, prefix: &str) -> std::result::Result<(), state::Error> {
70        self.conv1.load_state_dict(sd, &prefixed(prefix, "conv1"))?;
71        self.bn1.load_state_dict(sd, &prefixed(prefix, "bn1"))?;
72        self.conv2.load_state_dict(sd, &prefixed(prefix, "conv2"))?;
73        self.bn2.load_state_dict(sd, &prefixed(prefix, "bn2"))?;
74        self.conv3.load_state_dict(sd, &prefixed(prefix, "conv3"))?;
75        self.bn3.load_state_dict(sd, &prefixed(prefix, "bn3"))?;
76        if let Some((c, b)) = &mut self.downsample {
77            c.load_state_dict(sd, &prefixed(prefix, "downsample.0"))?;
78            b.load_state_dict(sd, &prefixed(prefix, "downsample.1"))?;
79        }
80        Ok(())
81    }
82}