Get Gentoo!
gentoo.org sites
gentoo.org Wiki Bugs Forums Packages
Planet Archives Sources
Infra Status
summaryrefslogtreecommitdiff
path: root/tesseract/src/training/common/networkbuilder.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'tesseract/src/training/common/networkbuilder.cpp')
-rw-r--r--tesseract/src/training/common/networkbuilder.cpp501
1 files changed, 501 insertions, 0 deletions
diff --git a/tesseract/src/training/common/networkbuilder.cpp b/tesseract/src/training/common/networkbuilder.cpp
new file mode 100644
index 00000000..763d9245
--- /dev/null
+++ b/tesseract/src/training/common/networkbuilder.cpp
@@ -0,0 +1,501 @@
+///////////////////////////////////////////////////////////////////////
+// File: networkbuilder.cpp
+// Description: Class to parse the network description language and
+// build a corresponding network.
+// Author: Ray Smith
+//
+// (C) Copyright 2014, Google Inc.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+///////////////////////////////////////////////////////////////////////
+
+#include "networkbuilder.h"
+
+#include "convolve.h"
+#include "fullyconnected.h"
+#include "input.h"
+#include "lstm.h"
+#include "maxpool.h"
+#include "network.h"
+#include "parallel.h"
+#include "reconfig.h"
+#include "reversed.h"
+#include "series.h"
+#include "unicharset.h"
+
+namespace tesseract {
+
+// Builds a network with a network_spec in the network description
+// language, to recognize a character set of num_outputs size.
+// If append_index is non-negative, then *network must be non-null and the
+// given network_spec will be appended to *network AFTER append_index, with
+// the top of the input *network discarded.
+// Note that network_spec is call by value to allow a non-const char* pointer
+// into the string for BuildFromString.
+// net_flags control network behavior according to the NetworkFlags enum.
+// The resulting network is returned via **network.
+// Returns false if something failed.
+bool NetworkBuilder::InitNetwork(int num_outputs, const char* network_spec,
+ int append_index, int net_flags,
+ float weight_range, TRand* randomizer,
+ Network** network) {
+ NetworkBuilder builder(num_outputs);
+ Series* bottom_series = nullptr;
+ StaticShape input_shape;
+ if (append_index >= 0) {
+ // Split the current network after the given append_index.
+ ASSERT_HOST(*network != nullptr && (*network)->type() == NT_SERIES);
+ auto* series = static_cast<Series*>(*network);
+ Series* top_series = nullptr;
+ series->SplitAt(append_index, &bottom_series, &top_series);
+ if (bottom_series == nullptr || top_series == nullptr) {
+ tprintf("Yikes! Splitting current network failed!!\n");
+ return false;
+ }
+ input_shape = bottom_series->OutputShape(input_shape);
+ delete top_series;
+ }
+ *network = builder.BuildFromString(input_shape, &network_spec);
+ if (*network == nullptr) return false;
+ (*network)->SetNetworkFlags(net_flags);
+ (*network)->InitWeights(weight_range, randomizer);
+ (*network)->SetupNeedsBackprop(false);
+ if (bottom_series != nullptr) {
+ bottom_series->AppendSeries(*network);
+ *network = bottom_series;
+ }
+ (*network)->CacheXScaleFactor((*network)->XScaleFactor());
+ return true;
+}
+
+// Helper skips whitespace.
+static void SkipWhitespace(const char** str) {
+ while (**str == ' ' || **str == '\t' || **str == '\n') ++*str;
+}
+
+// Parses the given string and returns a network according to the network
+// description language in networkbuilder.h
+Network* NetworkBuilder::BuildFromString(const StaticShape& input_shape,
+ const char** str) {
+ SkipWhitespace(str);
+ char code_ch = **str;
+ if (code_ch == '[') {
+ return ParseSeries(input_shape, nullptr, str);
+ }
+ if (input_shape.depth() == 0) {
+ // There must be an input at this point.
+ return ParseInput(str);
+ }
+ switch (code_ch) {
+ case '(':
+ return ParseParallel(input_shape, str);
+ case 'R':
+ return ParseR(input_shape, str);
+ case 'S':
+ return ParseS(input_shape, str);
+ case 'C':
+ return ParseC(input_shape, str);
+ case 'M':
+ return ParseM(input_shape, str);
+ case 'L':
+ return ParseLSTM(input_shape, str);
+ case 'F':
+ return ParseFullyConnected(input_shape, str);
+ case 'O':
+ return ParseOutput(input_shape, str);
+ default:
+ tprintf("Invalid network spec:%s\n", *str);
+ return nullptr;
+ }
+ return nullptr;
+}
+
+// Parses an input specification and returns the result, which may include a
+// series.
+Network* NetworkBuilder::ParseInput(const char** str) {
+ // There must be an input at this point.
+ int length = 0;
+ int batch, height, width, depth;
+ int num_converted =
+ sscanf(*str, "%d,%d,%d,%d%n", &batch, &height, &width, &depth, &length);
+ StaticShape shape;
+ shape.SetShape(batch, height, width, depth);
+ // num_converted may or may not include the length.
+ if (num_converted != 4 && num_converted != 5) {
+ tprintf("Must specify an input layer as the first layer, not %s!!\n", *str);
+ return nullptr;
+ }
+ *str += length;
+ Input* input = new Input("Input", shape);
+ // We want to allow [<input>rest of net... or <input>[rest of net... so we
+ // have to check explicitly for '[' here.
+ SkipWhitespace(str);
+ if (**str == '[') return ParseSeries(shape, input, str);
+ return input;
+}
+
+// Parses a sequential series of networks, defined by [<net><net>...].
+Network* NetworkBuilder::ParseSeries(const StaticShape& input_shape,
+ Input* input_layer, const char** str) {
+ StaticShape shape = input_shape;
+ Series* series = new Series("Series");
+ ++*str;
+ if (input_layer != nullptr) {
+ series->AddToStack(input_layer);
+ shape = input_layer->OutputShape(shape);
+ }
+ Network* network = nullptr;
+ while (**str != '\0' && **str != ']' &&
+ (network = BuildFromString(shape, str)) != nullptr) {
+ shape = network->OutputShape(shape);
+ series->AddToStack(network);
+ }
+ if (**str != ']') {
+ tprintf("Missing ] at end of [Series]!\n");
+ delete series;
+ return nullptr;
+ }
+ ++*str;
+ return series;
+}
+
+// Parses a parallel set of networks, defined by (<net><net>...).
+Network* NetworkBuilder::ParseParallel(const StaticShape& input_shape,
+ const char** str) {
+ Parallel* parallel = new Parallel("Parallel", NT_PARALLEL);
+ ++*str;
+ Network* network = nullptr;
+ while (**str != '\0' && **str != ')' &&
+ (network = BuildFromString(input_shape, str)) != nullptr) {
+ parallel->AddToStack(network);
+ }
+ if (**str != ')') {
+ tprintf("Missing ) at end of (Parallel)!\n");
+ delete parallel;
+ return nullptr;
+ }
+ ++*str;
+ return parallel;
+}
+
+// Parses a network that begins with 'R'.
+Network* NetworkBuilder::ParseR(const StaticShape& input_shape, const char** str) {
+ char dir = (*str)[1];
+ if (dir == 'x' || dir == 'y') {
+ std::string name = "Reverse";
+ name += dir;
+ *str += 2;
+ Network* network = BuildFromString(input_shape, str);
+ if (network == nullptr) return nullptr;
+ auto* rev =
+ new Reversed(name, dir == 'y' ? NT_YREVERSED : NT_XREVERSED);
+ rev->SetNetwork(network);
+ return rev;
+ }
+ char* end;
+ int replicas = strtol(*str + 1, &end, 10);
+ *str = end;
+ if (replicas <= 0) {
+ tprintf("Invalid R spec!:%s\n", end);
+ return nullptr;
+ }
+ Parallel* parallel = new Parallel("Replicated", NT_REPLICATED);
+ const char* str_copy = *str;
+ for (int i = 0; i < replicas; ++i) {
+ str_copy = *str;
+ Network* network = BuildFromString(input_shape, &str_copy);
+ if (network == nullptr) {
+ tprintf("Invalid replicated network!\n");
+ delete parallel;
+ return nullptr;
+ }
+ parallel->AddToStack(network);
+ }
+ *str = str_copy;
+ return parallel;
+}
+
+// Parses a network that begins with 'S'.
+Network* NetworkBuilder::ParseS(const StaticShape& input_shape, const char** str) {
+ char* end;
+ int y = strtol(*str + 1, &end, 10);
+ *str = end;
+ if (**str == ',') {
+ int x = strtol(*str + 1, &end, 10);
+ *str = end;
+ if (y <= 0 || x <= 0) {
+ tprintf("Invalid S spec!:%s\n", *str);
+ return nullptr;
+ }
+ return new Reconfig("Reconfig", input_shape.depth(), x, y);
+ } else if (**str == '(') {
+ // TODO(rays) Add Generic reshape.
+ tprintf("Generic reshape not yet implemented!!\n");
+ return nullptr;
+ }
+ tprintf("Invalid S spec!:%s\n", *str);
+ return nullptr;
+}
+
+// Helper returns the fully-connected type for the character code.
+static NetworkType NonLinearity(char func) {
+ switch (func) {
+ case 's':
+ return NT_LOGISTIC;
+ case 't':
+ return NT_TANH;
+ case 'r':
+ return NT_RELU;
+ case 'l':
+ return NT_LINEAR;
+ case 'm':
+ return NT_SOFTMAX;
+ case 'p':
+ return NT_POSCLIP;
+ case 'n':
+ return NT_SYMCLIP;
+ default:
+ return NT_NONE;
+ }
+}
+
+// Parses a network that begins with 'C'.
+Network* NetworkBuilder::ParseC(const StaticShape& input_shape, const char** str) {
+ NetworkType type = NonLinearity((*str)[1]);
+ if (type == NT_NONE) {
+ tprintf("Invalid nonlinearity on C-spec!: %s\n", *str);
+ return nullptr;
+ }
+ int y = 0, x = 0, d = 0;
+ char* end;
+ if ((y = strtol(*str + 2, &end, 10)) <= 0 || *end != ',' ||
+ (x = strtol(end + 1, &end, 10)) <= 0 || *end != ',' ||
+ (d = strtol(end + 1, &end, 10)) <= 0) {
+ tprintf("Invalid C spec!:%s\n", end);
+ return nullptr;
+ }
+ *str = end;
+ if (x == 1 && y == 1) {
+ // No actual convolution. Just a FullyConnected on the current depth, to
+ // be slid over all batch,y,x.
+ return new FullyConnected("Conv1x1", input_shape.depth(), d, type);
+ }
+ Series* series = new Series("ConvSeries");
+ Convolve* convolve =
+ new Convolve("Convolve", input_shape.depth(), x / 2, y / 2);
+ series->AddToStack(convolve);
+ StaticShape fc_input = convolve->OutputShape(input_shape);
+ series->AddToStack(new FullyConnected("ConvNL", fc_input.depth(), d, type));
+ return series;
+}
+
+// Parses a network that begins with 'M'.
+Network* NetworkBuilder::ParseM(const StaticShape& input_shape, const char** str) {
+ int y = 0, x = 0;
+ char* end;
+ if ((*str)[1] != 'p' || (y = strtol(*str + 2, &end, 10)) <= 0 ||
+ *end != ',' || (x = strtol(end + 1, &end, 10)) <= 0) {
+ tprintf("Invalid Mp spec!:%s\n", *str);
+ return nullptr;
+ }
+ *str = end;
+ return new Maxpool("Maxpool", input_shape.depth(), x, y);
+}
+
+// Parses an LSTM network, either individual, bi- or quad-directional.
+Network* NetworkBuilder::ParseLSTM(const StaticShape& input_shape, const char** str) {
+ bool two_d = false;
+ NetworkType type = NT_LSTM;
+ const char* spec_start = *str;
+ int chars_consumed = 1;
+ int num_outputs = 0;
+ char key = (*str)[chars_consumed], dir = 'f', dim = 'x';
+ if (key == 'S') {
+ type = NT_LSTM_SOFTMAX;
+ num_outputs = num_softmax_outputs_;
+ ++chars_consumed;
+ } else if (key == 'E') {
+ type = NT_LSTM_SOFTMAX_ENCODED;
+ num_outputs = num_softmax_outputs_;
+ ++chars_consumed;
+ } else if (key == '2' && (((*str)[2] == 'x' && (*str)[3] == 'y') ||
+ ((*str)[2] == 'y' && (*str)[3] == 'x'))) {
+ chars_consumed = 4;
+ dim = (*str)[3];
+ two_d = true;
+ } else if (key == 'f' || key == 'r' || key == 'b') {
+ dir = key;
+ dim = (*str)[2];
+ if (dim != 'x' && dim != 'y') {
+ tprintf("Invalid dimension (x|y) in L Spec!:%s\n", *str);
+ return nullptr;
+ }
+ chars_consumed = 3;
+ if ((*str)[chars_consumed] == 's') {
+ ++chars_consumed;
+ type = NT_LSTM_SUMMARY;
+ }
+ } else {
+ tprintf("Invalid direction (f|r|b) in L Spec!:%s\n", *str);
+ return nullptr;
+ }
+ char* end;
+ int num_states = strtol(*str + chars_consumed, &end, 10);
+ if (num_states <= 0) {
+ tprintf("Invalid number of states in L Spec!:%s\n", *str);
+ return nullptr;
+ }
+ *str = end;
+ Network* lstm = nullptr;
+ if (two_d) {
+ lstm = BuildLSTMXYQuad(input_shape.depth(), num_states);
+ } else {
+ if (num_outputs == 0) num_outputs = num_states;
+ std::string name(spec_start, *str - spec_start);
+ lstm = new LSTM(name, input_shape.depth(), num_states, num_outputs, false,
+ type);
+ if (dir != 'f') {
+ Reversed* rev = new Reversed("RevLSTM", NT_XREVERSED);
+ rev->SetNetwork(lstm);
+ lstm = rev;
+ }
+ if (dir == 'b') {
+ name += "LTR";
+ Parallel* parallel = new Parallel("BidiLSTM", NT_PAR_RL_LSTM);
+ parallel->AddToStack(new LSTM(name, input_shape.depth(), num_states,
+ num_outputs, false, type));
+ parallel->AddToStack(lstm);
+ lstm = parallel;
+ }
+ }
+ if (dim == 'y') {
+ Reversed* rev = new Reversed("XYTransLSTM", NT_XYTRANSPOSE);
+ rev->SetNetwork(lstm);
+ lstm = rev;
+ }
+ return lstm;
+}
+
+// Builds a set of 4 lstms with x and y reversal, running in true parallel.
+Network* NetworkBuilder::BuildLSTMXYQuad(int num_inputs, int num_states) {
+ Parallel* parallel = new Parallel("2DLSTMQuad", NT_PAR_2D_LSTM);
+ parallel->AddToStack(new LSTM("L2DLTRDown", num_inputs, num_states,
+ num_states, true, NT_LSTM));
+ Reversed* rev = new Reversed("L2DLTRXRev", NT_XREVERSED);
+ rev->SetNetwork(new LSTM("L2DRTLDown", num_inputs, num_states, num_states,
+ true, NT_LSTM));
+ parallel->AddToStack(rev);
+ rev = new Reversed("L2DRTLYRev", NT_YREVERSED);
+ rev->SetNetwork(
+ new LSTM("L2DRTLUp", num_inputs, num_states, num_states, true, NT_LSTM));
+ Reversed* rev2 = new Reversed("L2DXRevU", NT_XREVERSED);
+ rev2->SetNetwork(rev);
+ parallel->AddToStack(rev2);
+ rev = new Reversed("L2DXRevY", NT_YREVERSED);
+ rev->SetNetwork(new LSTM("L2DLTRDown", num_inputs, num_states, num_states,
+ true, NT_LSTM));
+ parallel->AddToStack(rev);
+ return parallel;
+}
+
+// Helper builds a truly (0-d) fully connected layer of the given type.
+static Network* BuildFullyConnected(const StaticShape& input_shape,
+ NetworkType type, const std::string& name,
+ int depth) {
+ if (input_shape.height() == 0 || input_shape.width() == 0) {
+ tprintf("Fully connected requires positive height and width, had %d,%d\n",
+ input_shape.height(), input_shape.width());
+ return nullptr;
+ }
+ int input_size = input_shape.height() * input_shape.width();
+ int input_depth = input_size * input_shape.depth();
+ Network* fc = new FullyConnected(name, input_depth, depth, type);
+ if (input_size > 1) {
+ Series* series = new Series("FCSeries");
+ series->AddToStack(new Reconfig("FCReconfig", input_shape.depth(),
+ input_shape.width(), input_shape.height()));
+ series->AddToStack(fc);
+ fc = series;
+ }
+ return fc;
+}
+
+// Parses a Fully connected network.
+Network* NetworkBuilder::ParseFullyConnected(const StaticShape& input_shape,
+ const char** str) {
+ const char* spec_start = *str;
+ NetworkType type = NonLinearity((*str)[1]);
+ if (type == NT_NONE) {
+ tprintf("Invalid nonlinearity on F-spec!: %s\n", *str);
+ return nullptr;
+ }
+ char* end;
+ int depth = strtol(*str + 2, &end, 10);
+ if (depth <= 0) {
+ tprintf("Invalid F spec!:%s\n", *str);
+ return nullptr;
+ }
+ *str = end;
+ std::string name(spec_start, *str - spec_start);
+ return BuildFullyConnected(input_shape, type, name, depth);
+}
+
+// Parses an Output spec.
+Network* NetworkBuilder::ParseOutput(const StaticShape& input_shape,
+ const char** str) {
+ char dims_ch = (*str)[1];
+ if (dims_ch != '0' && dims_ch != '1' && dims_ch != '2') {
+ tprintf("Invalid dims (2|1|0) in output spec!:%s\n", *str);
+ return nullptr;
+ }
+ char type_ch = (*str)[2];
+ if (type_ch != 'l' && type_ch != 's' && type_ch != 'c') {
+ tprintf("Invalid output type (l|s|c) in output spec!:%s\n", *str);
+ return nullptr;
+ }
+ char* end;
+ int depth = strtol(*str + 3, &end, 10);
+ if (depth != num_softmax_outputs_) {
+ tprintf("Warning: given outputs %d not equal to unicharset of %d.\n", depth,
+ num_softmax_outputs_);
+ depth = num_softmax_outputs_;
+ }
+ *str = end;
+ NetworkType type = NT_SOFTMAX;
+ if (type_ch == 'l')
+ type = NT_LOGISTIC;
+ else if (type_ch == 's')
+ type = NT_SOFTMAX_NO_CTC;
+ if (dims_ch == '0') {
+ // Same as standard fully connected.
+ return BuildFullyConnected(input_shape, type, "Output", depth);
+ } else if (dims_ch == '2') {
+ // We don't care if x and/or y are variable.
+ return new FullyConnected("Output2d", input_shape.depth(), depth, type);
+ }
+ // For 1-d y has to be fixed, and if not 1, moved to depth.
+ if (input_shape.height() == 0) {
+ tprintf("Fully connected requires fixed height!\n");
+ return nullptr;
+ }
+ int input_size = input_shape.height();
+ int input_depth = input_size * input_shape.depth();
+ Network* fc = new FullyConnected("Output", input_depth, depth, type);
+ if (input_size > 1) {
+ Series* series = new Series("FCSeries");
+ series->AddToStack(new Reconfig("FCReconfig", input_shape.depth(), 1,
+ input_shape.height()));
+ series->AddToStack(fc);
+ fc = series;
+ }
+ return fc;
+}
+
+} // namespace tesseract.