EasyCV/easycv/predictors/classifier.py

125 lines
4.6 KiB
Python

# Copyright (c) Alibaba, Inc. and its affiliates.
import math
import numpy as np
import torch
from .base import Predictor
from .builder import PREDICTORS
try:
from easy_vision.python.inference.predictor import PredictorInterface
except:
from .interface import PredictorInterface
@PREDICTORS.register_module()
class TorchClassifier(PredictorInterface):
def __init__(self,
model_path,
model_config=None,
topk=1,
label_map_path=None):
"""
init model
Args:
model_path: model file path
model_config: config string for model to init, in json format
"""
self.predictor = Predictor(model_path)
if 'class_list' not in self.predictor.cfg and label_map_path is None:
raise Exception(
"label_map_path need to be set, when ckpt doesn't contain class_list"
)
if label_map_path is None:
class_list = self.predictor.cfg.get('class_list', [])
self.label_map = [i.strip() for i in class_list]
else:
class_list = open(label_map_path).readlines()
self.label_map = [i.strip() for i in class_list]
self.output_name = ['prob', 'class']
self.topk = topk if topk < len(class_list) else len(class_list)
def get_output_type(self):
"""
in this function user should return a type dict, which indicates
which type of data should the output of predictor be converted to
* type json, data will be serialized to json str
* type image, data will be converted to encode image binary and write to oss file,
whose name is output_dir/${key}/${input_filename}_${idx}.jpg, where input_filename
is the base filename extracted from url, key corresponds to the key in the dict of output_type,
if the type of data indexed by key is a list, idx is the index of element in list, otherwhile ${idx} will be empty
* type video, data will be converted to encode video binary and write to oss file,
:: return {
'image': 'image',
'feature': 'json'
}
indicating that the image data in the output dict will be save to image
file and feature in output dict will be converted to json
"""
return {}
def batch(self, image_tensor_list):
return torch.stack(image_tensor_list)
def predict(self, input_data_list, batch_size=-1):
"""
using session run predict a number of samples using batch_size
Args:
input_data_list: a list of numpy array, each array is a sample to be predicted
batch_size: batch_size passed by the caller, you can also ignore this param and
use a fixed number if you do not want to adjust batch_size in runtime
Return:
result: a list of dict, each dict is the prediction result of one sample
eg, {"output1": value1, "output2": value2}, the value type can be
python int str float, and numpy array
"""
num_image = len(input_data_list)
assert len(
input_data_list) > 0, 'input images should not be an empty list'
if batch_size > 0:
num_batches = int(math.ceil(float(num_image) / batch_size))
image_list = input_data_list
else:
num_batches = 1
batch_size = len(input_data_list)
image_list = input_data_list
outputs_list = []
for batch_idx in range(num_batches):
batch_image_list = image_list[batch_idx * batch_size:min(
(batch_idx + 1) * batch_size, len(image_list))]
image_tensor_list = self.predictor.preprocess(batch_image_list)
input_data = self.batch(image_tensor_list)
output_prob = self.predictor.predict_batch(
input_data, mode='test')['prob'].data.cpu()
topk_prob = torch.topk(output_prob, self.topk).values.numpy()
topk_class = torch.topk(output_prob, self.topk).indices.numpy()
output_prob = output_prob.numpy()
for idx in range(len(image_tensor_list)):
single_result = {}
single_result['class'] = np.squeeze(topk_class[idx]).tolist()
if isinstance(single_result['class'], int):
single_result['class'] = [single_result['class']]
single_result['class_name'] = [
self.label_map[i] for i in single_result['class']
]
single_result['class_probs'] = {}
for ldx, i in enumerate(self.label_map):
single_result['class_probs'][i] = output_prob[idx][ldx]
outputs_list.append(single_result)
return outputs_list