Class ov::pass::ConvToBinaryConv#

class ConvToBinaryConv : public ov::pass::MatcherPass #

This transformation converts Convolution to BinaryConvolution under following conditions:

first input to Convolution is a FakeQuantize with levels==2 with output low,high being either (0, 1) or (-1, 1)

second input (weights) is a constant with values -1 or 1 The transformation also converts weights to binary Constant (with ‘u1’ type) For example, when output_low is equal to 0 and output_high is equal to 1, following graph

 .... ....  out_low   out_high
   |    |      |         |
  +--------------------------+           +-------------------------------------+
  | FakeQuantize (levels==2) |           |               Constant              |
  |     (on activations)     |           | (weights containing -1 or 1 values) |
  +--------------------------+           +-------------------------------------+
                |                                      |
                |                                      |
                -----------------    -------------------
                                |    |
                                v    v
                           +-------------+
                           | Convolution |
                           +-------------+
                                  |
                                  v

is transformed to:

 .... ....  out_low   out_high
   |    |      |         |
  +--------------------------+           +---------------------------------+
  | FakeQuantize (levels==2) |           |     Constant (with u1 type)     |
  |     (on activations)     |           | (with u1 type - binary weights) |
  +--------------------------+           +---------------------------------+
                |                                      |
                |                                      |
                -----------------    -------------------
                                |    |
                                v    v
                        +-------------------+
                        | BinaryConvolution |
                        +-------------------+
                                  |
                                  v
                           +------------+     +----------------------------------------------------+
                           |            |     |                   Constant                         |
                           |     Add    | <---|          (weights from original graph,             |
                           |            |     |  sum-reduced over [1,..., len(weights.shape)] axes |
                           +------------+     +----------------------------------------------------+
                                  |
                                  v
                           +------------+     +-----+
                           |  Multiply  | <---| 0.5 |
                           +------------+     +-----+
                                  |
                                  v