Allintra: add a unit test for deltaq-mode = 3

The test makes sure that when row_mt is turned off, deltaq-mode=3
could properly work.

BUG=aomedia:3433

Change-Id: I366c1ba3d5b087de5167605b980887319aaa8618
diff --git a/test/deltaq_mode_test.cc b/test/deltaq_mode_test.cc
index 38e25fb..5960d27 100644
--- a/test/deltaq_mode_test.cc
+++ b/test/deltaq_mode_test.cc
@@ -85,6 +85,67 @@
   EXPECT_EQ(AOM_CODEC_OK, aom_codec_destroy(&enc));
 }
 
+// The implementation of multi-threading for deltaq-mode=3 in allintra
+// mode is based on row multi-threading.
+// The test ensures that When row mt is turned off,
+// deltaq-mode = 3 can still properly encode and decode.
+TEST(DeltaqModeTest, DeltaqMode3MultiThreadNoRowMT) {
+  constexpr int kWidth = 1280;
+  constexpr int kHeight = 720;
+  // Dummy buffer of neutral gray samples.
+  constexpr size_t kBufferSize = kWidth * kHeight + kWidth * kHeight / 2;
+  std::vector<unsigned char> buffer(kBufferSize,
+                                    static_cast<unsigned char>(128));
+
+  aom_image_t img;
+  EXPECT_EQ(&img, aom_img_wrap(&img, AOM_IMG_FMT_I420, kWidth, kHeight, 1,
+                               buffer.data()));
+
+  aom_codec_iface_t *iface = aom_codec_av1_cx();
+  aom_codec_enc_cfg_t cfg;
+  EXPECT_EQ(aom_codec_enc_config_default(iface, &cfg, AOM_USAGE_GOOD_QUALITY),
+            AOM_CODEC_OK);
+  cfg.g_w = kWidth;
+  cfg.g_h = kHeight;
+  cfg.g_threads = 10;
+  cfg.rc_end_usage = AOM_Q;
+  cfg.g_profile = 0;
+  cfg.g_bit_depth = AOM_BITS_8;
+  cfg.g_input_bit_depth = 8;
+  cfg.g_lag_in_frames = 0;
+  cfg.rc_min_quantizer = 0;
+  cfg.rc_max_quantizer = 63;
+  cfg.g_pass = AOM_RC_ONE_PASS;
+  cfg.g_limit = 1;
+  aom_codec_ctx_t enc;
+  EXPECT_EQ(aom_codec_enc_init(&enc, iface, &cfg, 0), AOM_CODEC_OK);
+  EXPECT_EQ(aom_codec_control(&enc, AV1E_SET_ROW_MT, 0), AOM_CODEC_OK);
+  EXPECT_EQ(aom_codec_control(&enc, AOME_SET_CPUUSED, 6), AOM_CODEC_OK);
+  EXPECT_EQ(aom_codec_control(&enc, AOME_SET_CQ_LEVEL, 14), AOM_CODEC_OK);
+  EXPECT_EQ(aom_codec_control(&enc, AV1E_SET_DELTAQ_MODE, 3), AOM_CODEC_OK);
+  EXPECT_EQ(aom_codec_set_option(&enc, "passes", "1"), AOM_CODEC_OK);
+  EXPECT_EQ(aom_codec_control(&enc, AV1E_SET_COLOR_RANGE, AOM_CR_STUDIO_RANGE),
+            AOM_CODEC_OK);
+
+  EXPECT_EQ(aom_codec_encode(&enc, &img, 0, 1, 0), AOM_CODEC_OK);
+  aom_codec_iter_t iter = nullptr;
+  const aom_codec_cx_pkt_t *pkt = aom_codec_get_cx_data(&enc, &iter);
+  ASSERT_NE(pkt, nullptr);
+  EXPECT_EQ(pkt->kind, AOM_CODEC_CX_FRAME_PKT);
+  // pkt->data.frame.flags is 0x1f0011.
+  EXPECT_EQ(pkt->data.frame.flags & AOM_FRAME_IS_KEY, AOM_FRAME_IS_KEY);
+  pkt = aom_codec_get_cx_data(&enc, &iter);
+  EXPECT_EQ(pkt, nullptr);
+
+  // Flush encoder
+  EXPECT_EQ(AOM_CODEC_OK, aom_codec_encode(&enc, nullptr, 0, 1, 0));
+  iter = nullptr;
+  pkt = aom_codec_get_cx_data(&enc, &iter);
+  EXPECT_EQ(pkt, nullptr);
+
+  EXPECT_EQ(AOM_CODEC_OK, aom_codec_destroy(&enc));
+}
+
 #if CONFIG_AV1_HIGHBITDEPTH
 // 10-bit version of the DeltaqMode3MultiThread test.
 TEST(DeltaqModeTest, DeltaqMode3MultiThreadHighbd) {