## Lesson 3 - Regression with BIWI head pose dataset¶

This is a more advanced example to show how to create custom datasets and do regression with images. Our task is to find the center of the head in each image. The data comes from the BIWI head pose dataset, thanks to Gabriele Fanelli et al. We have converted the images to jpeg format, so you should download the converted dataset from this link.

In [1]:
%reload_ext autoreload
%matplotlib inline

In [2]:
from fastai import *
from fastai.vision import *


## Getting and converting the data¶

In [4]:
path = untar_data(URLs.BIWI_HEAD_POSE)

In [6]:
cal = np.genfromtxt(path / '01' / 'rgb.cal', skip_footer=6)
cal

Out[6]:
array([[517.679,   0.   , 320.   ],
[  0.   , 517.679, 240.5  ],
[  0.   ,   0.   ,   1.   ]])
In [18]:
fname = '09/frame_00667_rgb.jpg'

In [8]:
def img2txt_name(f): return path / f'{str(f)[:-7]}pose.txt'

In [20]:
img = open_image(path / fname)

In [21]:
img = open_image(path / fname)

In [22]:
img.show()

In [23]:
ctr = np.genfromtxt(img2txt_name(fname), skip_header=3)
ctr

Out[23]:
array([187.332 ,  40.3892, 893.135 ])
In [24]:
def convert_biwi(coords):
c1 = coords[0] * cal[0][0]/coords[2] + cal[0][2]
c2 = coords[1] * cal[1][1]/coords[2] + cal[1][2]
return tensor([c2, c1])

def get_ctr(f):
return convert_biwi(ctr)

def get_ip(img, pts): return ImagePoints(FlowField(img.size, pts), scale=True)

In [25]:
get_ctr(fname)

Out[25]:
tensor([263.9104, 428.5814])
In [26]:
ctr = get_ctr(fname)
img.show(y=get_ip(img, ctr), figsize=(6, 6))


## Creating a dataset¶

In [38]:
!ls /home/cedric/.fastai/data/biwi_head_pose/

01	04	07	10	13	16	19	22	io_sample.cpp
01.obj	04.obj	07.obj	10.obj	13.obj	16.obj	19.obj	22.obj	readme.txt
02	05	08	11	14	17	20	23
02.obj	05.obj	08.obj	11.obj	14.obj	17.obj	20.obj	23.obj
03	06	09	12	15	18	21	24
03.obj	06.obj	09.obj	12.obj	15.obj	18.obj	21.obj	24.obj

In [39]:
data = (PointsItemList.from_folder(path)
.split_by_valid_func(lambda o: o.parent.name=='13')
.label_from_func(get_ctr)
.transform(get_transforms(), tfm_y=True, size=(120,160))
.databunch().normalize(imagenet_stats)
)

In [40]:
data.show_batch(3, figsize=(9,6))


## Train model¶

In [41]:
learn = create_cnn(data, models.resnet34)

In [42]:
learn.lr_find()
learn.recorder.plot()

LR Finder is complete, type {learner_name}.recorder.plot() to see the graph.

In [43]:
lr = 2e-2

In [44]:
learn.fit_one_cycle(5, slice(lr))

Total time: 04:08

epoch train_loss valid_loss
1 0.053352 0.040483
2 0.018844 0.011221
3 0.009006 0.001588
4 0.005284 0.000702
5 0.004040 0.001096
In [45]:
learn.save('stage-1')

In [46]:
learn.load('stage-1')

Out[46]:
Learner(data=ImageDataBunch;

Train: LabelList
y: PointsLabelList (15193 items)
[ImagePoints (480, 640), ImagePoints (480, 640), ImagePoints (480, 640), ImagePoints (480, 640), ImagePoints (480, 640)]...
x: PointsItemList (15193 items)
[Image (3, 480, 640), Image (3, 480, 640), Image (3, 480, 640), Image (3, 480, 640), Image (3, 480, 640)]...

Valid: LabelList
y: PointsLabelList (485 items)
[ImagePoints (480, 640), ImagePoints (480, 640), ImagePoints (480, 640), ImagePoints (480, 640), ImagePoints (480, 640)]...
x: PointsItemList (485 items)
[Image (3, 480, 640), Image (3, 480, 640), Image (3, 480, 640), Image (3, 480, 640), Image (3, 480, 640)]...

Test: None, model=Sequential(
(0): Sequential(
(0): Conv2d(3, 64, kernel_size=(7, 7), stride=(2, 2), padding=(3, 3), bias=False)
(1): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(2): ReLU(inplace)
(3): MaxPool2d(kernel_size=3, stride=2, padding=1, dilation=1, ceil_mode=False)
(4): Sequential(
(0): BasicBlock(
(conv1): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn1): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(relu): ReLU(inplace)
(conv2): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn2): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
)
(1): BasicBlock(
(conv1): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn1): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(relu): ReLU(inplace)
(conv2): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn2): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
)
(2): BasicBlock(
(conv1): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn1): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(relu): ReLU(inplace)
(conv2): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn2): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
)
)
(5): Sequential(
(0): BasicBlock(
(conv1): Conv2d(64, 128, kernel_size=(3, 3), stride=(2, 2), padding=(1, 1), bias=False)
(bn1): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(relu): ReLU(inplace)
(conv2): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn2): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(downsample): Sequential(
(0): Conv2d(64, 128, kernel_size=(1, 1), stride=(2, 2), bias=False)
(1): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
)
)
(1): BasicBlock(
(conv1): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn1): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(relu): ReLU(inplace)
(conv2): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn2): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
)
(2): BasicBlock(
(conv1): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn1): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(relu): ReLU(inplace)
(conv2): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn2): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
)
(3): BasicBlock(
(conv1): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn1): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(relu): ReLU(inplace)
(conv2): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn2): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
)
)
(6): Sequential(
(0): BasicBlock(
(conv1): Conv2d(128, 256, kernel_size=(3, 3), stride=(2, 2), padding=(1, 1), bias=False)
(bn1): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(relu): ReLU(inplace)
(conv2): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn2): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(downsample): Sequential(
(0): Conv2d(128, 256, kernel_size=(1, 1), stride=(2, 2), bias=False)
(1): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
)
)
(1): BasicBlock(
(conv1): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn1): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(relu): ReLU(inplace)
(conv2): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn2): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
)
(2): BasicBlock(
(conv1): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn1): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(relu): ReLU(inplace)
(conv2): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn2): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
)
(3): BasicBlock(
(conv1): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn1): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(relu): ReLU(inplace)
(conv2): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn2): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
)
(4): BasicBlock(
(conv1): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn1): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(relu): ReLU(inplace)
(conv2): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn2): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
)
(5): BasicBlock(
(conv1): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn1): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(relu): ReLU(inplace)
(conv2): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn2): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
)
)
(7): Sequential(
(0): BasicBlock(
(conv1): Conv2d(256, 512, kernel_size=(3, 3), stride=(2, 2), padding=(1, 1), bias=False)
(bn1): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(relu): ReLU(inplace)
(conv2): Conv2d(512, 512, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn2): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(downsample): Sequential(
(0): Conv2d(256, 512, kernel_size=(1, 1), stride=(2, 2), bias=False)
(1): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
)
)
(1): BasicBlock(
(conv1): Conv2d(512, 512, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn1): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(relu): ReLU(inplace)
(conv2): Conv2d(512, 512, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn2): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
)
(2): BasicBlock(
(conv1): Conv2d(512, 512, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn1): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(relu): ReLU(inplace)
(conv2): Conv2d(512, 512, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(bn2): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
)
)
)
(1): Sequential(
)
(1): Lambda()
(2): BatchNorm1d(1024, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(3): Dropout(p=0.25)
(4): Linear(in_features=1024, out_features=512, bias=True)
(5): ReLU(inplace)
(6): BatchNorm1d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(7): Dropout(p=0.5)
(8): Linear(in_features=512, out_features=2, bias=True)
)
), opt_func=functools.partial(<class 'torch.optim.adam.Adam'>, betas=(0.9, 0.99)), loss_func=<fastai.layers.FlattenedLoss object at 0x7f7792ccd2b0>, metrics=[], true_wd=True, bn_wd=True, wd=0.01, train_bn=True, path=PosixPath('/home/cedric/.fastai/data/biwi_head_pose'), model_dir='models', callback_fns=[<class 'fastai.basic_train.Recorder'>], callbacks=[], layer_groups=[Sequential(
(0): Conv2d(3, 64, kernel_size=(7, 7), stride=(2, 2), padding=(3, 3), bias=False)
(1): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(2): ReLU(inplace)
(3): MaxPool2d(kernel_size=3, stride=2, padding=1, dilation=1, ceil_mode=False)
(4): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(5): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(6): ReLU(inplace)
(7): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(8): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(9): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(10): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(11): ReLU(inplace)
(12): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(13): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(14): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(15): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(16): ReLU(inplace)
(17): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(18): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(19): Conv2d(64, 128, kernel_size=(3, 3), stride=(2, 2), padding=(1, 1), bias=False)
(20): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(21): ReLU(inplace)
(22): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(23): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(24): Conv2d(64, 128, kernel_size=(1, 1), stride=(2, 2), bias=False)
(25): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(26): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(27): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(28): ReLU(inplace)
(29): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(30): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(31): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(32): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(33): ReLU(inplace)
(34): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(35): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(36): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(37): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(38): ReLU(inplace)
(39): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(40): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
), Sequential(
(0): Conv2d(128, 256, kernel_size=(3, 3), stride=(2, 2), padding=(1, 1), bias=False)
(1): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(2): ReLU(inplace)
(3): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(4): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(5): Conv2d(128, 256, kernel_size=(1, 1), stride=(2, 2), bias=False)
(6): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(7): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(8): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(9): ReLU(inplace)
(10): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(11): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(12): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(13): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(14): ReLU(inplace)
(15): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(16): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(17): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(18): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(19): ReLU(inplace)
(20): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(21): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(22): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(23): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(24): ReLU(inplace)
(25): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(26): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(27): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(28): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(29): ReLU(inplace)
(30): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(31): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(32): Conv2d(256, 512, kernel_size=(3, 3), stride=(2, 2), padding=(1, 1), bias=False)
(33): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(34): ReLU(inplace)
(35): Conv2d(512, 512, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(36): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(37): Conv2d(256, 512, kernel_size=(1, 1), stride=(2, 2), bias=False)
(38): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(39): Conv2d(512, 512, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(40): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(41): ReLU(inplace)
(42): Conv2d(512, 512, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(43): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(44): Conv2d(512, 512, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(45): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(46): ReLU(inplace)
(47): Conv2d(512, 512, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False)
(48): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
), Sequential(
(2): Lambda()
(3): BatchNorm1d(1024, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(4): Dropout(p=0.25)
(5): Linear(in_features=1024, out_features=512, bias=True)
(6): ReLU(inplace)
(7): BatchNorm1d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True)
(8): Dropout(p=0.5)
(9): Linear(in_features=512, out_features=2, bias=True)
)])
In [47]:
learn.show_results()


## Data augmentation¶

In [48]:
tfms = get_transforms(max_rotate=20, max_zoom=1.5, max_lighting=0.5, max_warp=0.4, p_affine=1., p_lighting=1.)

In [49]:
data = (ImageItemList.from_folder(path)
.split_by_valid_func(lambda o: o.parent.name == '13')
.label_from_func(get_ctr, label_cls=PointsItemList)
.databunch().normalize(imagenet_stats)
)

In [50]:
def _plot(i, j, ax):
x, y = data.train_ds[0]
x.show(ax, y=y)

plot_multi(_plot, 3, 3, figsize=(8,6))

---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
~/anaconda3/envs/fastai-v1/lib/python3.7/site-packages/PIL/Image.py in open(fp, mode)
2612     try:
-> 2613         fp.seek(0)
2614     except (AttributeError, io.UnsupportedOperation):

AttributeError: 'Tensor' object has no attribute 'seek'

During handling of the above exception, another exception occurred:

AttributeError                            Traceback (most recent call last)
<ipython-input-50-60a076c639f6> in <module>
3     x.show(ax, y=y)
4
----> 5 plot_multi(_plot, 3, 3, figsize=(8,6))

~/anaconda3/envs/fastai-v1/lib/python3.7/site-packages/fastai/vision/image.py in plot_multi(func, r, c, figsize)
589     axes = plt.subplots(r, c, figsize=figsize)[1]
590     for i in range(r):
--> 591         for j in range(c): func(i,j,axes[i,j])
592
593 def show_multi(func:Callable[[int,int],Image], r:int=1, c:int=1, figsize:Tuple=(9,9)):

<ipython-input-50-60a076c639f6> in _plot(i, j, ax)
1 def _plot(i, j, ax):
----> 2     x, y = data.train_ds[0]
3     x.show(ax, y=y)
4
5 plot_multi(_plot, 3, 3, figsize=(8,6))

~/anaconda3/envs/fastai-v1/lib/python3.7/site-packages/fastai/data_block.py in __getitem__(self, idxs)
519         idxs = try_int(idxs)
520         if isinstance(idxs, numbers.Integral):
--> 521             if self.item is None: x,y = self.x[idxs],self.y[idxs]
522             else:                 x,y = self.item   ,0
523             if self.tfms:

~/anaconda3/envs/fastai-v1/lib/python3.7/site-packages/fastai/data_block.py in __getitem__(self, idxs)
92     def __getitem__(self,idxs:int)->Any:
93         idxs = try_int(idxs)
---> 94         if isinstance(idxs, numbers.Integral): return self.get(idxs)
95         else: return self.new(self.items[idxs], xtra=index_row(self.xtra, idxs))
96

~/anaconda3/envs/fastai-v1/lib/python3.7/site-packages/fastai/vision/data.py in get(self, i)
264     def get(self, i):
265         fn = super().get(i)
--> 266         res = self.open(fn)
267         self.sizes[i] = res.size
268         return res

~/anaconda3/envs/fastai-v1/lib/python3.7/site-packages/fastai/vision/data.py in open(self, fn)
260     def open(self, fn):
261         "Open image in fn, subclass and overwrite for custom behavior."
--> 262         return open_image(fn, convert_mode=self.convert_mode)
263
264     def get(self, i):

~/anaconda3/envs/fastai-v1/lib/python3.7/site-packages/fastai/vision/image.py in open_image(fn, div, convert_mode, cls)
374     with warnings.catch_warnings():
375         warnings.simplefilter("ignore", UserWarning) # EXIF warning from TiffPlugin
--> 376         x = PIL.Image.open(fn).convert(convert_mode)
377     x = pil2tensor(x,np.float32)
378     if div: x.div_(255)

~/anaconda3/envs/fastai-v1/lib/python3.7/site-packages/PIL/Image.py in open(fp, mode)
2613         fp.seek(0)
2614     except (AttributeError, io.UnsupportedOperation):
AttributeError: 'Tensor' object has no attribute 'read'