title: Unable to load pre-trained model checkpoint with TensorFlow Object Detection API
body: <p>Similar to this question:</p>
  <p><a href="https://stackoverflow.com/questions/49507040/where-can-i-find-model-ckpt-in-faster-rcnn-resnet50-coco-model">Where can I find model.ckpt in faster_rcnn_resnet50_coco model?</a> (this solution doesn't work for me)</p>
  <p>I have downloaded the <code>ssd_resnet152_v1_fpn_1024x1024_coco17_tpu-8</code> with the intention of using it as a starting point. I am using the sample model configuration associated with that model in the TF model zoo.</p>
  <p>I am only changing the num classes and paths for tuning, training and eval.</p>
  <p>With:</p>
  <pre><code>fine_tune_checkpoint: &quot;C:\\Users\\Peter\\Desktop\\Adv-ML-Project\\models\\research\\object_detection\\test_data\\checkpoint\\model.ckpt&quot;
  </code></pre>
  <p>I get:</p>
  <pre><code>tensorflow.python.framework.errors_impl.NotFoundError: Unsuccessful TensorSliceReader constructor: Failed to find any matching files for C:\Users\Pierre\Desktop\Adv-ML-Project\models\research\object_detection\test_data\checkpoint\model.ckpt
  </code></pre>
  <p>With:</p>
  <pre><code>fine_tune_checkpoint: &quot;C:\\Users\\Peter\\Desktop\\Adv-ML-Project\\models\\research\\object_detection\\test_data\\checkpoint\\ckpt-0.*&quot;
  </code></pre>
  <p>I get:</p>
  <pre><code>tensorflow.python.framework.errors_impl.DataLossError: Unable to open table file C:\Users\Pierre\Desktop\Adv-ML-Project\models\research\object_detection\test_data\checkpoint\ckpt-0.data-00000-of-00001: Data loss: not an sstable (bad mag
  ic number): perhaps your file is in a different file format and you need to use a different restore operator?
  </code></pre>
  <p>I'm currently using absolute paths because it's easiest, but if it's a problem I can re-organize my project structure.</p>
  <p><a href="https://i.stack.imgur.com/UQr81.png" rel="nofollow noreferrer">Checkpoint Folder</a></p>
  <p>The official documentation from <a href="https://github.com/tensorflow/models/blob/master/research/object_detection/g3doc/tf2_training_and_evaluation.md" rel="nofollow noreferrer">https://github.com/tensorflow/models/blob/master/research/object_detection/g3doc/tf2_training_and_evaluation.md</a>
  says to do something like</p>
  <pre><code>fine_tune_checkpoint: a path prefix to the pre-existing checkpoint (ie:&quot;/usr/home/username/checkpoint/model.ckpt-#####&quot;).
  </code></pre>
  <p>Is there something I am doing wrong here? I am running this with the following command (also from documentation):</p>
  <pre><code>python object_detection/model_main_tf2.py \
      --pipeline_config_path=&quot;C:\\Users\Pierre\\Desktop\\Adv-ML-Project\\models\\my_model\\my_model.config&quot; \
      --model_dir=&quot;C:\\Users\\Pierre\\Desktop\\Adv-ML-Project\\models\\my_model\\training&quot; \
      --alsologtostderr
  </code></pre>