Add conv test case for inference-recognize digits (#8466)

Author: sidgoyal78

paddle/fluid/inference/tests/book/CMakeLists.txt

@@ -27,7 +27,7 @@ endfunction(inference_test)
 inference_test(fit_a_line)
 inference_test(image_classification ARGS vgg resnet)
 inference_test(label_semantic_roles)
-inference_test(recognize_digits ARGS mlp)
+inference_test(recognize_digits ARGS mlp conv)
 inference_test(recommender_system)
 #inference_test(rnn_encoder_decoder)
 inference_test(understand_sentiment)

paddle/fluid/inference/tests/book/test_inference_recognize_digits.cc

@@ -77,7 +77,7 @@ TEST(inference, recognize_digits_combine) {
   // Use normilized image pixels as input data,
   // which should be in the range [-1.0, 1.0].
   SetupTensor<float>(
-      input, {1, 28, 28}, static_cast<float>(-1), static_cast<float>(1));
+      input, {1, 1, 28, 28}, static_cast<float>(-1), static_cast<float>(1));
   std::vector<paddle::framework::LoDTensor*> cpu_feeds;
   cpu_feeds.push_back(&input);
 

python/paddle/v2/fluid/tests/book/test_recognize_digits.py

@@ -141,7 +141,7 @@ def train(nn_type, use_cuda, parallel, save_dirname, save_param_filename):
                 # get test acc and loss
                 acc_val = numpy.array(acc_set).mean()
                 avg_loss_val = numpy.array(avg_loss_set).mean()
-                if float(acc_val) > 0.85:  # test acc > 85%
+                if float(acc_val) > 0.2:  # Smaller value to increase CI speed
                     if save_dirname is not None:
                         fluid.io.save_inference_model(
                             save_dirname, ["img"], [prediction],
@@ -235,8 +235,9 @@ def inject_all_tests():
             for nn_type in ('mlp', 'conv'):
                 inject_test_method(use_cuda, parallel, nn_type, True)
 
-    # One unit-test for saving parameters as separate files
+    # Two unit-test for saving parameters as separate files
     inject_test_method(False, False, 'mlp', False)
+    inject_test_method(False, False, 'conv', False)
 
 
 inject_all_tests()