ocr识别，单一的ctc-head输出，使用MultiScaleSampler，精度一直为0，loss为nanxxx，使用SimpleDataSet精度正常

[zhangxiaopang88]

Architecture:
model_type: rec
algorithm: SVTR
Transform:
Backbone:
name: PPLCNetV3
scale: 0.95
Neck:
name: SequenceEncoder
encoder_type: reshape
Head:
name: CTCHead
#fc_decay: 0.00001

Loss:
name: CTCLoss

PostProcess:
name: CTCLabelDecode

Metric:
name: RecMetric
main_indicator: acc

Train:
dataset:
name: MultiScaleDataSet
ds_width: false
data_dir: ./
ext_op_transform_idx: 1
label_file_list:
- data/train.txt
transforms:
- DecodeImage:
img_mode: BGR
channel_first: false
- RecConAug:
prob: 0.5
ext_data_num: 2
image_shape: [48, 128, 3]
max_text_length: *max_text_length
- RecAug:
- MultiLabelEncode:
gtc_encode: NRTRLabelEncode
- KeepKeys:
keep_keys:
- image
- label_ctc
- label_gtc
- length
- valid_ratio
sampler:
name: MultiScaleSampler
scales: [[128, 32], [128, 48], [128, 64]]
first_bs: &bs 192
fix_bs: false
divided_factor: [8, 16] # w, h
is_training: True
loader:
shuffle: true
batch_size_per_card: *bs
drop_last: true
num_workers: 16
Eval:
dataset:
name: SimpleDataSet
data_dir: ./
label_file_list:
- data/eval.txt
transforms:
- DecodeImage:
img_mode: BGR
channel_first: false
- MultiLabelEncode:
gtc_encode: NRTRLabelEncode
- RecResizeImg:
image_shape: [3, 48, 128]
- KeepKeys:
keep_keys:
- image
- label_ctc
- label_gtc
- length
- valid_ratio
loader:
shuffle: false
drop_last: false
batch_size_per_card: 128
num_workers: 16

log一直是这样
ppocr INFO: epoch: [1/200], global_step: 1580, lr: 0.000004, acc: 0.000000, norm_edit_dis: 0.000000, loss: nanxxx, avg_reader_cost: 0.00013 s, avg_batch_cost: 0.32655 s, avg_samples: 147.2, ips: 450.77714 samples/s, eta: 6 days, 4:14:47

[IbrarBabar009]

is your problem solved?