How to display custom images in TensorBoard using Keras?

Question

I\'m working on a segmentation problem in Keras and I want to display segmentation results at the end of every training epoch.

I want something similar to Tensorflow

Answer 1

Here is example how to draw landmarks on image:

class CustomCallback(keras.callbacks.Callback):
    def __init__(self, model, generator):
        self.generator = generator
        self.model = model

    def tf_summary_image(self, tensor):
        import io
        from PIL import Image

        tensor = tensor.astype(np.uint8)

        height, width, channel = tensor.shape
        image = Image.fromarray(tensor)
        output = io.BytesIO()
        image.save(output, format='PNG')
        image_string = output.getvalue()
        output.close()
        return tf.Summary.Image(height=height,
                             width=width,
                             colorspace=channel,
                             encoded_image_string=image_string)

    def on_epoch_end(self, epoch, logs={}):
        frames_arr, landmarks = next(self.generator)

        # Take just 1st sample from batch
        frames_arr = frames_arr[0:1,...]

        y_pred = self.model.predict(frames_arr)

        # Get last frame for which we have done predictions
        img = frames_arr[0,-1,:,:]

        img = img * 255
        img = img[:, :, ::-1]
        img = np.copy(img)

        landmarks_gt = landmarks[-1].reshape(-1,2)
        landmarks_pred = y_pred.reshape(-1,2)

        img = draw_landmarks(img, landmarks_gt, (0,255,0))
        img = draw_landmarks(img, landmarks_pred, (0,0,255))

        image = self.tf_summary_image(img)
        summary = tf.Summary(value=[tf.Summary.Value(image=image)])
        writer = tf.summary.FileWriter('./logs')
        writer.add_summary(summary, epoch)
        writer.close()
        return