目录
👉 本周任务:
● 请根据YOLOv8n、YOLOv8s模型的结构输出,手写出YOLOv8l的模型输出
文件位置:./ultralytics/cfg/models/v8/yolov8.yaml
- # Parameters
- nc: 80 # number of classes
- scales: # model compound scaling constants, i.e. 'model=yolov8n.yaml' will call yolov8.yaml with scale 'n'
- # [depth, width, max_channels]
- n: [0.33, 0.25, 1024] # YOLOv8n summary: 225 layers, 3157200 parameters, 3157184 gradients, 8.9 GFLOPs
- s: [0.33, 0.50, 1024] # YOLOv8s summary: 225 layers, 11166560 parameters, 11166544 gradients, 28.8 GFLOPs
- m: [0.67, 0.75, 768] # YOLOv8m summary: 295 layers, 25902640 parameters, 25902624 gradients, 79.3 GFLOPs
- l: [1.00, 1.00, 512] # YOLOv8l summary: 365 layers, 43691520 parameters, 43691504 gradients, 165.7 GFLOPs
- x: [1.00, 1.25, 512] # YOLOv8x summary: 365 layers, 68229648 parameters, 68229632 gradients, 258.5 GFLOPs
Parameters:
nc:80 是类别数量,即模型可以识别的物体类别数。
scales: 包含了不同模型配置的尺度参数,英语调整模型的规模,通过尺度参数可以实现不同复杂度的模型设计。YOLOv8n、YOLOv8s、YOLOv8m、YOLOv8l、YOLOv8x五种模型的区别在于depth、width、max_channels这三个参数的不同。
depth: 深度,控制子模块的数量, = int(number*depth)
width: 宽度,控制卷积核的数量, = int(number*width)
max_channels: 最大通道数
- backbone:
- # [from, repeats, module, args]
- - [-1, 1, Conv, [64, 3, 2]] # 0-P1/2
- - [-1, 1, Conv, [128, 3, 2]] # 1-P2/4
- - [-1, 3, C2f, [128, True]]
- - [-1, 1, Conv, [256, 3, 2]] # 3-P3/8
- - [-1, 6, C2f, [256, True]]
- - [-1, 1, Conv, [512, 3, 2]] # 5-P4/16
- - [-1, 6, C2f, [512, True]]
- - [-1, 1, Conv, [1024, 3, 2]] # 7-P5/32
- - [-1, 3, C2f, [1024, True]]
- - [-1, 1, SPPF, [1024, 5]] # 9
YOLOv8的backbone,每一个模块算一行,每行由四个参数构成。分别是:
from:表示当前模块的输入来自那一层的输出,-1表示来自上一层的输出,层编号由0开始计数。
repeats:表示当前模块的理论重复次数,实际的重复次数还要由上面的参数depth_multiple共同决定,该参数影响整体网络模型的深度。
model:模块类名,通过这个类名在common.py中寻找相应的类,进行模块化的搭建网络。
args:是一个list,模块搭建所需参数,channel,kernel_size,stride,padding,bias等。
这个模块是YOLOv8的主干网络(backbone),用于提取输入图像的特征以便后续的目标检测任务。YOLOv8的主干网络采用了一些标准的卷积神经网络模块,例如卷积层(Conv)、深度可分离卷积层(C2f)以及空间金字塔池化层(SPPF)。它们在不同层数级上增强了网络的表示能力和视野范围,使之更好地适应各种尺寸的输入图像。该模块的输入是一份图像,输出是多个不同层数级的特征图(feature maps),它们将传递给输出头部(output heads)以产生物体检测的结果。
- head:
- 1. [-1, 1, nn.Upsample, [None, 2, "nearest"]]
- 2. [[-1, 6], 1, Concat, [1]] # cat backbone P4
- 3. [-1, 3, C2f, [512]] # 12
-
- 4. [-1, 1, nn.Upsample, [None, 2, "nearest"]]
- 5. [[-1, 4], 1, Concat, [1]] # cat backbone P3
- 6. [-1, 3, C2f, [256]] # 15 (P3/8-small)
-
- 7. [-1, 1, Conv, [256, 3, 2]]
- 8. [[-1, 12], 1, Concat, [1]] # cat head P4
- 9. [-1, 3, C2f, [512]] # 18 (P4/16-medium)
-
- 10. [-1, 1, Conv, [512, 3, 2]]
- 11. [[-1, 9], 1, Concat, [1]] # cat head P5
- 12. [-1, 3, C2f, [1024]] # 21 (P5/32-large)
-
- 13. [[15, 18, 21], 1, Detect, [nc]] # Detect(P3, P4, P5)
这个模块是YOLOv8的输出头(head),用于将主干网络(backbone)的特征图(feature maps)转化为目标检测的输出结果。该模块主要包括三个部分,即上采样(Upsample)、特征融合(Concat)和检测(Detect)层。其中,上采样层将不同层数级的特征图进行放大以便它们能够进行特征融合。特征融合层将不同层数级的特征图拼接起来,产生更加丰富和全面的特征表示,并使得检测器能够对不同大小、不同位置的物体进行检测。最后,检测层将特征图通过多个卷积层(Conv)和恰当的激活函数进行处理,以产生物体检测的结果,包括类别、置信度和边界框坐标等信息。在YOLOv8中,检测层称为Detect层,它接收来自不同层数级的特征图,使用卷积和全连接层对它们进行处理,最终输出目标检测的结果。
- from n params module arguments
- 0 -1 1 464 ultralytics.nn.modules.conv.Conv [3, 16, 3, 2]
- 1 -1 1 4672 ultralytics.nn.modules.conv.Conv [16, 32, 3, 2]
- 2 -1 1 7360 ultralytics.nn.modules.block.C2f [32, 32, 1, True]
- 3 -1 1 18560 ultralytics.nn.modules.conv.Conv [32, 64, 3, 2]
- 4 -1 2 49664 ultralytics.nn.modules.block.C2f [64, 64, 2, True]
- 5 -1 1 73984 ultralytics.nn.modules.conv.Conv [64, 128, 3, 2]
- 6 -1 2 197632 ultralytics.nn.modules.block.C2f [128, 128, 2, True]
- 7 -1 1 295424 ultralytics.nn.modules.conv.Conv [128, 256, 3, 2]
- 8 -1 1 460288 ultralytics.nn.modules.block.C2f [256, 256, 1, True]
- 9 -1 1 164608 ultralytics.nn.modules.block.SPPF [256, 256, 5]
- 10 -1 1 0 torch.nn.modules.upsampling.Upsample [None, 2, 'nearest']
- 11 [-1, 6] 1 0 ultralytics.nn.modules.conv.Concat [1]
- 12 -1 1 148224 ultralytics.nn.modules.block.C2f [384, 128, 1]
- 13 -1 1 0 torch.nn.modules.upsampling.Upsample [None, 2, 'nearest']
- 14 [-1, 4] 1 0 ultralytics.nn.modules.conv.Concat [1]
- 15 -1 1 37248 ultralytics.nn.modules.block.C2f [192, 64, 1]
- 16 -1 1 36992 ultralytics.nn.modules.conv.Conv [64, 64, 3, 2]
- 17 [-1, 12] 1 0 ultralytics.nn.modules.conv.Concat [1]
- 18 -1 1 123648 ultralytics.nn.modules.block.C2f [192, 128, 1]
- 19 -1 1 147712 ultralytics.nn.modules.conv.Conv [128, 128, 3, 2]
- 20 [-1, 9] 1 0 ultralytics.nn.modules.conv.Concat [1]
- 21 -1 1 493056 ultralytics.nn.modules.block.C2f [384, 256, 1]
- 22 [15, 18, 21] 1 752092 ultralytics.nn.modules.head.Detect [4, [64, 128, 256]]
- YOLOv8n summary: 225 layers, 3011628 parameters, 3011612 gradients, 8.2 GFLOPs
- from n params module arguments
- 0 -1 1 928 ultralytics.nn.modules.conv.Conv [3, 32, 3, 2]
- 1 -1 1 18560 ultralytics.nn.modules.conv.Conv [32, 64, 3, 2]
- 2 -1 1 29056 ultralytics.nn.modules.block.C2f [64, 64, 1, True]
- 3 -1 1 73984 ultralytics.nn.modules.conv.Conv [64, 128, 3, 2]
- 4 -1 2 197632 ultralytics.nn.modules.block.C2f [128, 128, 2, True]
- 5 -1 1 295424 ultralytics.nn.modules.conv.Conv [128, 256, 3, 2]
- 6 -1 2 788480 ultralytics.nn.modules.block.C2f [256, 256, 2, True]
- 7 -1 1 1180672 ultralytics.nn.modules.conv.Conv [256, 512, 3, 2]
- 8 -1 1 1838080 ultralytics.nn.modules.block.C2f [512, 512, 1, True]
- 9 -1 1 656896 ultralytics.nn.modules.block.SPPF [512, 512, 5]
- 10 -1 1 0 torch.nn.modules.upsampling.Upsample [None, 2, 'nearest']
- 11 [-1, 6] 1 0 ultralytics.nn.modules.conv.Concat [1]
- 12 -1 1 591360 ultralytics.nn.modules.block.C2f [768, 256, 1]
- 13 -1 1 0 torch.nn.modules.upsampling.Upsample [None, 2, 'nearest']
- 14 [-1, 4] 1 0 ultralytics.nn.modules.conv.Concat [1]
- 15 -1 1 148224 ultralytics.nn.modules.block.C2f [384, 128, 1]
- 16 -1 1 147712 ultralytics.nn.modules.conv.Conv [128, 128, 3, 2]
- 17 [-1, 12] 1 0 ultralytics.nn.modules.conv.Concat [1]
- 18 -1 1 493056 ultralytics.nn.modules.block.C2f [384, 256, 1]
- 19 -1 1 590336 ultralytics.nn.modules.conv.Conv [256, 256, 3, 2]
- 20 [-1, 9] 1 0 ultralytics.nn.modules.conv.Concat [1]
- 21 -1 1 1969152 ultralytics.nn.modules.block.C2f [768, 512, 1]
- 22 [15, 18, 21] 1 2117596 ultralytics.nn.modules.head.Detect [4, [128, 256, 512]]
- YOLOv8s summary: 225 layers, 11137148 parameters, 11137132 gradients, 28.7 GFLOPs
- from n params module arguments
- 0 -1 1 1856 ultralytics.nn.modules.conv.Conv [3, 64, 3, 2]
- 1 -1 1 73984 ultralytics.nn.modules.conv.Conv [64, 128, 3, 2]
- 2 -1 3 279808 ultralytics.nn.modules.block.C2f [128, 128, 3, True]
- 3 -1 1 295424 ultralytics.nn.modules.conv.Conv [128, 256, 3, 2]
- 4 -1 6 2101248 ultralytics.nn.modules.block.C2f [256, 256, 6, True]
- 5 -1 1 1180672 ultralytics.nn.modules.conv.Conv [256, 512, 3, 2]
- 6 -1 6 8396800 ultralytics.nn.modules.block.C2f [512, 512, 6, True]
- 7 -1 1 2360320 ultralytics.nn.modules.conv.Conv [512, 512, 3, 2]
- 8 -1 3 4461568 ultralytics.nn.modules.block.C2f [512, 512, 3, True]
- 9 -1 1 656896 ultralytics.nn.modules.block.SPPF [512, 512, 5]
- 10 -1 1 0 torch.nn.modules.upsampling.Upsample [None, 2, 'nearest']
- 11 [-1, 6] 1 0 ultralytics.nn.modules.conv.Concat [1]
- 12 -1 3 4723712 ultralytics.nn.modules.block.C2f [1024, 512, 3]
- 13 -1 1 0 torch.nn.modules.upsampling.Upsample [None, 2, 'nearest']
- 14 [-1, 4] 1 0 ultralytics.nn.modules.conv.Concat [1]
- 15 -1 3 1247744 ultralytics.nn.modules.block.C2f [768, 256, 3]
- 16 -1 1 590336 ultralytics.nn.modules.conv.Conv [256, 256, 3, 2]
- 17 [-1, 12] 1 0 ultralytics.nn.modules.conv.Concat [1]
- 18 -1 3 4592640 ultralytics.nn.modules.block.C2f [768, 512, 3]
- 19 -1 1 2360320 ultralytics.nn.modules.conv.Conv [512, 512, 3, 2]
- 20 [-1, 9] 1 0 ultralytics.nn.modules.conv.Concat [1]
- 21 -1 3 4723712 ultralytics.nn.modules.block.C2f [1024, 512, 3]
- 22 [15, 18, 21] 1 5585884 ultralytics.nn.modules.head.Detect [4, [256, 512, 512]]
- YOLOv8l summary: 365 layers, 43632924 parameters, 43632908 gradients, 165.4 GFLOPs
本周的任务:基于YOLOv8n和YOLOv8s模型的结构,手写出YOLOv8l的模型输出。为了完成这个任务,我首先深入分析了yolov8.yaml的参数配置,这让我对模型的细节有了更深入的理解。接着,我研究了backbone模块和head模块,这些是模型中至关重要的部分。
通过分析YOLOv8n和YOLOv8s,我能够逐步构建出YOLOv8l.yaml文件的模型结构输出。这个过程不仅考验了我的技术能力,还锻炼了我的逻辑思维和问题解决能力。在比较不同模型结构时,我注意到了它们在性能和效率上的权衡,这让我对深度学习模型设计有了更深刻的认识。