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### `tf.nn.ctc_beam_search_decoder(inputs, sequence_length, beam_width=100, top_paths=1, merge_repeated=True)` {#ctc_beam_search_decoder}
Performs beam search decoding on the logits given in input.
**Note** The `ctc_greedy_decoder` is a special case of the
`ctc_beam_search_decoder` with `top_paths=1` and `beam_width=1` (but
that decoder is faster for this special case).
If `merge_repeated` is `True`, merge repeated classes in the output beams.
This means that if consecutive entries in a beam are the same,
only the first of these is emitted. That is, when the top path
is `A B B B B`, the return value is:
* `A B` if `merge_repeated = True`.
* `A B B B B` if `merge_repeated = False`.
##### Args:
* <b>`inputs`</b>: 3-D `float` `Tensor`, size
`[max_time x batch_size x num_classes]`. The logits.
* <b>`sequence_length`</b>: 1-D `int32` vector containing sequence lengths,
having size `[batch_size]`.
* <b>`beam_width`</b>: An int scalar >= 0 (beam search beam width).
* <b>`top_paths`</b>: An int scalar >= 0, <= beam_width (controls output size).
* <b>`merge_repeated`</b>: Boolean. Default: True.
##### Returns:
A tuple `(decoded, log_probabilities)` where
* <b>`decoded`</b>: A list of length top_paths, where `decoded[j]`
is a `SparseTensor` containing the decoded outputs:
`decoded[j].indices`: Indices matrix `(total_decoded_outputs[j] x 2)`
The rows store: [batch, time].
`decoded[j].values`: Values vector, size `(total_decoded_outputs[j])`.
The vector stores the decoded classes for beam j.
`decoded[j].shape`: Shape vector, size `(2)`.
The shape values are: `[batch_size, max_decoded_length[j]]`.
* <b>`log_probability`</b>: A `float` matrix `(batch_size x top_paths)` containing
sequence log-probabilities.
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