tf.raw_ops.FakeQuantWithMinMaxArgs

Fake-quantize the 'inputs' tensor, type float to 'outputs' tensor of same shape and type.

Quantization is called fake since the output is still in floating point. The API converts inputs into values within the range [min and max] and returns as output.

Attributes

  • [min; max] define the clamping range for the inputs data.
  • inputs values are quantized into the quantization range ( [0; 2^num_bits - 1] when narrow_range is false and [1; 2^num_bits - 1] when it is true) and then de-quantized and output as floats in [min; max] interval.
  • num_bits is the bitwidth of the quantization; between 2 and 16, inclusive.

Before quantization, min and max values are adjusted with the following logic. It is suggested to have min <= 0 <= max. If 0 is not in the range of values, the behavior can be unexpected:

  • If 0 < min < max: min_adj = 0 and max_adj = max - min.
  • If min < max < 0: min_adj = min - max and max_adj = 0.
  • If min <= 0 <= max: scale = (max - min) / (2^num_bits - 1), min_adj = scale * round(min / scale) and max_adj = max + min_adj - min.

Examples


inp = tf.constant ([10.03, -10.23, 3])
out = tf.quantization.fake_quant_with_min_max_args(inp, min=-5, max=5,
                                                   num_bits=16)
print(out)

#  Output:
#  tf.Tensor([ 4.9999237 -5.0000763  3.0000763], shape=(3,), dtype=float32)

  • InvalidArgumentError:
    • If num_bits are outside of range [2, 16].
    • If min >= max.
  • ValueError: If inputs are of any other type than float32.

inputs A Tensor of type float32.
min An optional float. Defaults to -6.
max An optional float. Defaults to 6.
num_bits An optional int. Defaults to 8.
narrow_range An optional bool. Defaults to False.
name A name for the operation (optional).

A Tensor of type float32.