Import aom library

This is the reference implementation for the Alliance for Open Media's av1 video code.

The commit used was 4d668d7feb1f8abd809d1bca0418570a7f142a36.

third_party/aom/test/accounting_test.cc

@@ -0,0 +1,78 @@
+/*
+ * Copyright (c) 2016, Alliance for Open Media. All rights reserved
+ *
+ * This source code is subject to the terms of the BSD 2 Clause License and
+ * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
+ * was not distributed with this source code in the LICENSE file, you can
+ * obtain it at www.aomedia.org/license/software. If the Alliance for Open
+ * Media Patent License 1.0 was not distributed with this source code in the
+ * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
+*/
+
+#include <math.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "third_party/googletest/src/googletest/include/gtest/gtest.h"
+
+#include "test/acm_random.h"
+#include "aom/aom_integer.h"
+#include "aom_dsp/bitreader.h"
+#include "aom_dsp/bitwriter.h"
+
+using libaom_test::ACMRandom;
+
+TEST(AV1, TestAccounting) {
+  const int kBufferSize = 10000;
+  const int kSymbols = 1024;
+  aom_writer bw;
+  uint8_t bw_buffer[kBufferSize];
+  aom_start_encode(&bw, bw_buffer);
+  for (int i = 0; i < kSymbols; i++) {
+    aom_write(&bw, 0, 32);
+    aom_write(&bw, 0, 32);
+    aom_write(&bw, 0, 32);
+  }
+  aom_stop_encode(&bw);
+  aom_reader br;
+#if CONFIG_ANS && ANS_MAX_SYMBOLS
+  br.window_size = 1 << 16;
+#endif
+  aom_reader_init(&br, bw_buffer, bw.pos, NULL, NULL);
+
+  Accounting accounting;
+  aom_accounting_init(&accounting);
+  br.accounting = &accounting;
+  for (int i = 0; i < kSymbols; i++) {
+    aom_read(&br, 32, "A");
+  }
+  // Consecutive symbols that are the same are coalesced.
+  GTEST_ASSERT_EQ(accounting.syms.num_syms, 1);
+  GTEST_ASSERT_EQ(accounting.syms.syms[0].samples, (unsigned int)kSymbols);
+
+  aom_accounting_reset(&accounting);
+  GTEST_ASSERT_EQ(accounting.syms.num_syms, 0);
+
+  // Should record 2 * kSymbols accounting symbols.
+  aom_reader_init(&br, bw_buffer, bw.pos, NULL, NULL);
+  br.accounting = &accounting;
+  for (int i = 0; i < kSymbols; i++) {
+    aom_read(&br, 32, "A");
+    aom_read(&br, 32, "B");
+    aom_read(&br, 32, "B");
+  }
+  GTEST_ASSERT_EQ(accounting.syms.num_syms, kSymbols * 2);
+  uint32_t tell_frac = aom_reader_tell_frac(&br);
+  for (int i = 0; i < accounting.syms.num_syms; i++) {
+    tell_frac -= accounting.syms.syms[i].bits;
+  }
+  GTEST_ASSERT_EQ(tell_frac, 0U);
+
+  GTEST_ASSERT_EQ(aom_accounting_dictionary_lookup(&accounting, "A"),
+                  aom_accounting_dictionary_lookup(&accounting, "A"));
+
+  // Check for collisions. The current aom_accounting_hash function returns
+  // the same hash code for AB and BA.
+  GTEST_ASSERT_NE(aom_accounting_dictionary_lookup(&accounting, "AB"),
+                  aom_accounting_dictionary_lookup(&accounting, "BA"));
+}