LXMERT visual feature extraction during training/fine-tuning phase
# 🚀 Feature request

Thanks a lot for releasing LXMERT model. In the LXMERT model code samples, the visual feature extraction code (using generalized faster-rcnn: [modeling_frcnn](https://github.com/huggingface/transformers/blob/master/examples/lxmert/modeling_frcnn.py)) only in the inference step is given. However, the visual feature extraction during the training phase is not given. For this reason if we use the same code for fine-tuning, it raises NotImplementedError as the visual feature extraction during training is not implemented. Is it possible to share the visual feature extraction during training?
Yes, I also came up with this error. It would be great if the feature gets published. TIA.<|||||>Tagging LXMERT's implementation author @eltoto1219 <|||||>Haha, yes we only added the FRCNN for evaluation to accommodate lxmert in the demo. I'll add the training code sometime this week, and then post back here once it is done, in the future it may be useable as a publicly available model following the HF api, but for the time being ill just push the changes to where it is now. <|||||>Thanks for the prompt feedback. 
Looking forward to it. 
@eltoto1219 <|||||>@eltoto1219 thanks, that will be quite a help.<|||||>@eltoto1219 Looking forward to it.<|||||>This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.
<|||||>Hello, any updates on this? 😃 <|||||>Hi @LetiP, 

My apologies for the delay! I actually have a couple of conference deadlines mid-January and also some other projects after that, so my free time to implement training code for the FRCNN is unfortunately very limited. I think if I can still manage to add this functionality, it may not be ready until sometime in May. However, the code used for the FRCNN here was majorly adapted from Facebook's detectron2 library. I can point  you to the source training code incase you need this functionality sooner!

here is the file for the region proposal network: https://github.com/facebookresearch/detectron2/blob/e0e166d864a2021a15a2bc2c9234d04938066265/detectron2/modeling/proposal_generator/rpn.py#L402

here is the file for the box matcher: https://github.com/facebookresearch/detectron2/blob/master/detectron2/modeling/matcher.py

some utils for the rpn: https://github.com/facebookresearch/detectron2/blob/master/detectron2/modeling/proposal_generator/proposal_utils.py

code for the frcnn output predictions: https://github.com/facebookresearch/detectron2/blob/e0e166d864a2021a15a2bc2c9234d04938066265/detectron2/modeling/roi_heads/fast_rcnn.py#L433

not completely sure if changes are needed in this file for training: https://github.com/facebookresearch/detectron2/blob/master/detectron2/modeling/roi_heads/box_head.py

roi head logic: https://github.com/facebookresearch/detectron2/blob/e0e166d864a2021a15a2bc2c9234d04938066265/detectron2/modeling/roi_heads/roi_heads.py#L307


I may be able to provide some quick pointers if you run into anything that seems impossible to get working by replying more to this thread!<|||||>Rather than trying to "add training functionality" to the custom copy of an old subset of detectron2 in this repo, I can't see why you cannot just use detectron2 directly. That would not only provide the training functionality out of the box, but also probably reduce the 3000 lines of duplicated unmaintained code here into like 50 lines.<|||||>I want to use a frcnn model that is trained on a custom dataset. I followed the tutorials in the original detectron2 repo (Colab Notebooks in https://github.com/facebookresearch/detectron2). However, I noticed that the config file architecture for your pretrained model is different from mine. 
For example, this is the model part in your config file
"model :
    load_proposals: false
    device: cpu
    max_pool: true
    chkpoint: ""
    pixel_mean: [102.9801, 115.9465, 122.7717]
    pixel_std: [1.0, 1.0, 1.0]" 

And this is mine: 
"MODEL:
  ANCHOR_GENERATOR:
    ANGLES:
    - - -90
      - 0
      - 90
    ASPECT_RATIOS:
    - - 0.5
      - 1.0
      - 2.0
    NAME: DefaultAnchorGenerator
    OFFSET: 0.0
    SIZES:
    - - 32
    - - 64
    - - 128
    - - 256
    - - 512
  BACKBONE:
    FREEZE_AT: 2
    NAME: build_resnet_fpn_backbone
  DEVICE: cuda
  FPN:
    FUSE_TYPE: sum
    IN_FEATURES:
    - res2
    - res3
    - res4
    - res5
    NORM: ''
    OUT_CHANNELS: 256
  KEYPOINT_ON: false
  LOAD_PROPOSALS: false
  MASK_ON: true
  META_ARCHITECTURE: GeneralizedRCNN
  PANOPTIC_FPN:
    COMBINE:
      ENABLED: true
      INSTANCES_CONFIDENCE_THRESH: 0.5
      OVERLAP_THRESH: 0.5
      STUFF_AREA_LIMIT: 4096
    INSTANCE_LOSS_WEIGHT: 1.0
  PIXEL_MEAN:
  - 103.53
  - 116.28
  - 123.675
  PIXEL_STD:
  - 1.0
  - 1.0
  - 1.0
  PROPOSAL_GENERATOR:
    MIN_SIZE: 0
    NAME: RPN
  RESNETS:
    DEFORM_MODULATED: false
    DEFORM_NUM_GROUPS: 1
    DEFORM_ON_PER_STAGE:
    - false
    - false
    - false
    - false
    DEPTH: 50
    NORM: FrozenBN
    NUM_GROUPS: 1
    OUT_FEATURES:
    - res2
    - res3
    - res4
    - res5
    RES2_OUT_CHANNELS: 256
    RES5_DILATION: 1
    STEM_OUT_CHANNELS: 64
    STRIDE_IN_1X1: true
    WIDTH_PER_GROUP: 64
  RETINANET:
    BBOX_REG_LOSS_TYPE: smooth_l1
    BBOX_REG_WEIGHTS: &id001
    - 1.0
    - 1.0
    - 1.0
    - 1.0
    FOCAL_LOSS_ALPHA: 0.25
    FOCAL_LOSS_GAMMA: 2.0
    IN_FEATURES:
    - p3
    - p4
    - p5
    - p6
    - p7
    IOU_LABELS:
    - 0
    - -1
    - 1
    IOU_THRESHOLDS:
    - 0.4
    - 0.5
    NMS_THRESH_TEST: 0.5
    NORM: ''
    NUM_CLASSES: 80
    NUM_CONVS: 4
    PRIOR_PROB: 0.01
    SCORE_THRESH_TEST: 0.05
    SMOOTH_L1_LOSS_BETA: 0.1
    TOPK_CANDIDATES_TEST: 1000
  ROI_BOX_CASCADE_HEAD:
    BBOX_REG_WEIGHTS:
    - - 10.0
      - 10.0
      - 5.0
      - 5.0
    - - 20.0
      - 20.0
      - 10.0
      - 10.0
    - - 30.0
      - 30.0
      - 15.0
      - 15.0
    IOUS:
    - 0.5
    - 0.6
    - 0.7
  ROI_BOX_HEAD:
    BBOX_REG_LOSS_TYPE: smooth_l1
    BBOX_REG_LOSS_WEIGHT: 1.0
    BBOX_REG_WEIGHTS:
    - 10.0
    - 10.0
    - 5.0
    - 5.0
    CLS_AGNOSTIC_BBOX_REG: false
    CONV_DIM: 256
    FC_DIM: 1024
    NAME: FastRCNNConvFCHead
    NORM: ''
    NUM_CONV: 0
    NUM_FC: 2
    POOLER_RESOLUTION: 7
    POOLER_SAMPLING_RATIO: 0
    POOLER_TYPE: ROIAlignV2
    SMOOTH_L1_BETA: 0.0
    TRAIN_ON_PRED_BOXES: false
  ROI_HEADS:
    BATCH_SIZE_PER_IMAGE: 128
    IN_FEATURES:
    - p2
    - p3
    - p4
    - p5
    IOU_LABELS:
    - 0
    - 1
    IOU_THRESHOLDS:
    - 0.5
    NAME: StandardROIHeads
    NMS_THRESH_TEST: 0.5
    NUM_CLASSES: 1
    POSITIVE_FRACTION: 0.25
    PROPOSAL_APPEND_GT: true
    SCORE_THRESH_TEST: 0.7
  ROI_KEYPOINT_HEAD:
    CONV_DIMS:
    - 512
    - 512
    - 512
    - 512
    - 512
    - 512
    - 512
    - 512
    LOSS_WEIGHT: 1.0
    MIN_KEYPOINTS_PER_IMAGE: 1
    NAME: KRCNNConvDeconvUpsampleHead
    NORMALIZE_LOSS_BY_VISIBLE_KEYPOINTS: true
    NUM_KEYPOINTS: 17
    POOLER_RESOLUTION: 14
    POOLER_SAMPLING_RATIO: 0
    POOLER_TYPE: ROIAlignV2
  ROI_MASK_HEAD:
    CLS_AGNOSTIC_MASK: false
    CONV_DIM: 256
    NAME: MaskRCNNConvUpsampleHead
    NORM: ''
    NUM_CONV: 4
    POOLER_RESOLUTION: 14
    POOLER_SAMPLING_RATIO: 0
    POOLER_TYPE: ROIAlignV2
  RPN:
    BATCH_SIZE_PER_IMAGE: 256
    BBOX_REG_LOSS_TYPE: smooth_l1
    BBOX_REG_LOSS_WEIGHT: 1.0
    BBOX_REG_WEIGHTS: *id001
    BOUNDARY_THRESH: -1
    HEAD_NAME: StandardRPNHead
    IN_FEATURES:
    - p2
    - p3
    - p4
    - p5
    - p6
    IOU_LABELS:
    - 0
    - -1
    - 1
    IOU_THRESHOLDS:
    - 0.3
    - 0.7
    LOSS_WEIGHT: 1.0
    NMS_THRESH: 0.7
    POSITIVE_FRACTION: 0.5
    POST_NMS_TOPK_TEST: 1000
    POST_NMS_TOPK_TRAIN: 1000
    PRE_NMS_TOPK_TEST: 1000
    PRE_NMS_TOPK_TRAIN: 2000
    SMOOTH_L1_BETA: 0.0
  SEM_SEG_HEAD:
    COMMON_STRIDE: 4
    CONVS_DIM: 128
    IGNORE_VALUE: 255
    IN_FEATURES:
    - p2
    - p3
    - p4
    - p5
    LOSS_WEIGHT: 1.0
    NAME: SemSegFPNHead
    NORM: GN
    NUM_CLASSES: 54
  WEIGHTS: ./output/model_final.pth"

Could you please provide any resources how we can use our own trained frcnn models ? <|||||>This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

Please note that issues that do not follow the [contributing guidelines](https://github.com/huggingface/transformers/blob/master/CONTRIBUTING.md) are likely to be ignored.<|||||>Any update on this 🙂 ?