Reland "[ACM] iSAC audio codec removed"

This is a reland of commit b46c4bf27ba5c417fcba7f200d80fa4634e7e1a1

Original change's description:
> [ACM] iSAC audio codec removed
>
> Note: this CL has to leave behind one part of iSAC, which is its VAD
> currently used by AGC1 in APM. The target visibility has been
> restricted and the VAD will be removed together with AGC1 when the
> time comes.
>
> Tested: see https://chromium-review.googlesource.com/c/chromium/src/+/4013319
>
> Bug: webrtc:14450
> Change-Id: I69cc518b16280eae62a1f1977cdbfa24c08cf5f9
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/282421
> Reviewed-by: Henrik Lundin <henrik.lundin@webrtc.org>
> Reviewed-by: Sam Zackrisson <saza@webrtc.org>
> Reviewed-by: Henrik Boström <hbos@webrtc.org>
> Commit-Queue: Alessio Bazzica <alessiob@webrtc.org>
> Cr-Commit-Position: refs/heads/main@{#38652}

Bug: webrtc:14450
Change-Id: Ia22c4d7724b6022238235fede93e36e570a49376
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/283843
Reviewed-by: Henrik Lundin <henrik.lundin@webrtc.org>
Commit-Queue: Alessio Bazzica <alessiob@webrtc.org>
Reviewed-by: Sam Zackrisson <saza@webrtc.org>
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#38665}
diff --git a/modules/audio_coding/acm2/acm_receiver_unittest.cc b/modules/audio_coding/acm2/acm_receiver_unittest.cc
index e73acc2..6dd44b6 100644
--- a/modules/audio_coding/acm2/acm_receiver_unittest.cc
+++ b/modules/audio_coding/acm2/acm_receiver_unittest.cc
@@ -13,6 +13,7 @@
 #include <algorithm>  // std::min
 #include <memory>
 
+#include "absl/types/optional.h"
 #include "api/audio_codecs/builtin_audio_decoder_factory.h"
 #include "api/audio_codecs/builtin_audio_encoder_factory.h"
 #include "modules/audio_coding/codecs/cng/audio_encoder_cng.h"
@@ -64,12 +65,14 @@
                             const SdpAudioFormat& format,
                             const std::map<int, int> cng_payload_types = {}) {
     // Create the speech encoder.
-    AudioCodecInfo info = encoder_factory_->QueryAudioEncoder(format).value();
+    absl::optional<AudioCodecInfo> info =
+        encoder_factory_->QueryAudioEncoder(format);
+    RTC_CHECK(info.has_value());
     std::unique_ptr<AudioEncoder> enc =
         encoder_factory_->MakeAudioEncoder(payload_type, format, absl::nullopt);
 
     // If we have a compatible CN specification, stack a CNG on top.
-    auto it = cng_payload_types.find(info.sample_rate_hz);
+    auto it = cng_payload_types.find(info->sample_rate_hz);
     if (it != cng_payload_types.end()) {
       AudioEncoderCngConfig config;
       config.speech_encoder = std::move(enc);
@@ -81,7 +84,7 @@
 
     // Actually start using the new encoder.
     acm_->SetEncoder(std::move(enc));
-    return info;
+    return *info;
   }
 
   int InsertOnePacketOfSilence(const AudioCodecInfo& info) {
@@ -148,8 +151,7 @@
 #define MAYBE_SampleRate SampleRate
 #endif
 TEST_F(AcmReceiverTestOldApi, MAYBE_SampleRate) {
-  const std::map<int, SdpAudioFormat> codecs = {{0, {"ISAC", 16000, 1}},
-                                                {1, {"ISAC", 32000, 1}}};
+  const std::map<int, SdpAudioFormat> codecs = {{0, {"OPUS", 48000, 2}}};
   receiver_->SetCodecs(codecs);
 
   constexpr int kOutSampleRateHz = 8000;  // Different than codec sample rate.
@@ -233,15 +235,6 @@
 }
 
 #if defined(WEBRTC_ANDROID)
-#define MAYBE_VerifyAudioFrameISAC DISABLED_VerifyAudioFrameISAC
-#else
-#define MAYBE_VerifyAudioFrameISAC VerifyAudioFrameISAC
-#endif
-TEST_F(AcmReceiverTestFaxModeOldApi, MAYBE_VerifyAudioFrameISAC) {
-  RunVerifyAudioFrame({"ISAC", 16000, 1});
-}
-
-#if defined(WEBRTC_ANDROID)
 #define MAYBE_VerifyAudioFrameOpus DISABLED_VerifyAudioFrameOpus
 #else
 #define MAYBE_VerifyAudioFrameOpus VerifyAudioFrameOpus
@@ -310,12 +303,10 @@
 #else
 #define MAYBE_LastAudioCodec LastAudioCodec
 #endif
-#if defined(WEBRTC_CODEC_ISAC)
+#if defined(WEBRTC_CODEC_OPUS)
 TEST_F(AcmReceiverTestOldApi, MAYBE_LastAudioCodec) {
-  const std::map<int, SdpAudioFormat> codecs = {{0, {"ISAC", 16000, 1}},
-                                                {1, {"PCMA", 8000, 1}},
-                                                {2, {"ISAC", 32000, 1}},
-                                                {3, {"L16", 32000, 1}}};
+  const std::map<int, SdpAudioFormat> codecs = {
+      {0, {"PCMU", 8000, 1}}, {1, {"PCMA", 8000, 1}}, {2, {"L16", 32000, 1}}};
   const std::map<int, int> cng_payload_types = {
       {8000, 100}, {16000, 101}, {32000, 102}};
   {
diff --git a/modules/audio_coding/acm2/audio_coding_module_unittest.cc b/modules/audio_coding/acm2/audio_coding_module_unittest.cc
index 7e4b764..f1eb81c 100644
--- a/modules/audio_coding/acm2/audio_coding_module_unittest.cc
+++ b/modules/audio_coding/acm2/audio_coding_module_unittest.cc
@@ -30,7 +30,6 @@
 #include "modules/audio_coding/codecs/cng/audio_encoder_cng.h"
 #include "modules/audio_coding/codecs/g711/audio_decoder_pcm.h"
 #include "modules/audio_coding/codecs/g711/audio_encoder_pcm.h"
-#include "modules/audio_coding/codecs/isac/main/include/audio_encoder_isac.h"
 #include "modules/audio_coding/include/audio_coding_module_typedefs.h"
 #include "modules/audio_coding/neteq/tools/audio_checksum.h"
 #include "modules/audio_coding/neteq/tools/audio_loop.h"
@@ -302,44 +301,6 @@
   EXPECT_EQ(AudioFrameType::kAudioFrameSpeech, packet_cb_.last_frame_type());
 }
 
-#if defined(WEBRTC_CODEC_ISAC) || defined(WEBRTC_CODEC_ISACFX)
-// Verifies that the RTP timestamp series is not reset when the codec is
-// changed.
-TEST_F(AudioCodingModuleTestOldApi, TimestampSeriesContinuesWhenCodecChanges) {
-  RegisterCodec();  // This registers the default codec.
-  uint32_t expected_ts = input_frame_.timestamp_;
-  int blocks_per_packet = pac_size_ / (kSampleRateHz / 100);
-  // Encode 5 packets of the first codec type.
-  const int kNumPackets1 = 5;
-  for (int j = 0; j < kNumPackets1; ++j) {
-    for (int i = 0; i < blocks_per_packet; ++i) {
-      EXPECT_EQ(j, packet_cb_.num_calls());
-      InsertAudio();
-    }
-    EXPECT_EQ(j + 1, packet_cb_.num_calls());
-    EXPECT_EQ(expected_ts, packet_cb_.last_timestamp());
-    expected_ts += pac_size_;
-  }
-
-  // Change codec.
-  audio_format_ = SdpAudioFormat("ISAC", kSampleRateHz, 1);
-  pac_size_ = 480;
-  RegisterCodec();
-  blocks_per_packet = pac_size_ / (kSampleRateHz / 100);
-  // Encode another 5 packets.
-  const int kNumPackets2 = 5;
-  for (int j = 0; j < kNumPackets2; ++j) {
-    for (int i = 0; i < blocks_per_packet; ++i) {
-      EXPECT_EQ(kNumPackets1 + j, packet_cb_.num_calls());
-      InsertAudio();
-    }
-    EXPECT_EQ(kNumPackets1 + j + 1, packet_cb_.num_calls());
-    EXPECT_EQ(expected_ts, packet_cb_.last_timestamp());
-    expected_ts += pac_size_;
-  }
-}
-#endif
-
 // Introduce this class to set different expectations on the number of encoded
 // bytes. This class expects all encoded packets to be 9 bytes (matching one
 // CNG SID frame) or 0 bytes. This test depends on `input_frame_` containing
@@ -420,8 +381,7 @@
   DoTest(k10MsBlocksPerPacket, kCngPayloadType);
 }
 
-// A multi-threaded test for ACM. This base class is using the PCM16b 16 kHz
-// codec, while the derive class AcmIsacMtTest is using iSAC.
+// A multi-threaded test for ACM that uses the PCM16b 16 kHz codec.
 class AudioCodingModuleMtTestOldApi : public AudioCodingModuleTestOldApi {
  protected:
   static const int kNumPackets = 500;
@@ -560,272 +520,6 @@
   EXPECT_TRUE(RunTest());
 }
 
-// This is a multi-threaded ACM test using iSAC. The test encodes audio
-// from a PCM file. The most recent encoded frame is used as input to the
-// receiving part. Depending on timing, it may happen that the same RTP packet
-// is inserted into the receiver multiple times, but this is a valid use-case,
-// and simplifies the test code a lot.
-class AcmIsacMtTestOldApi : public AudioCodingModuleMtTestOldApi {
- protected:
-  static const int kNumPackets = 500;
-  static const int kNumPullCalls = 500;
-
-  AcmIsacMtTestOldApi()
-      : AudioCodingModuleMtTestOldApi(), last_packet_number_(0) {}
-
-  ~AcmIsacMtTestOldApi() {}
-
-  void SetUp() override {
-    AudioCodingModuleTestOldApi::SetUp();
-    RegisterCodec();  // Must be called before the threads start below.
-
-    // Set up input audio source to read from specified file, loop after 5
-    // seconds, and deliver blocks of 10 ms.
-    const std::string input_file_name =
-        webrtc::test::ResourcePath("audio_coding/speech_mono_16kHz", "pcm");
-    audio_loop_.Init(input_file_name, 5 * kSampleRateHz, kNumSamples10ms);
-
-    // Generate one packet to have something to insert.
-    int loop_counter = 0;
-    while (packet_cb_.last_payload_len_bytes() == 0) {
-      InsertAudio();
-      ASSERT_LT(loop_counter++, 10);
-    }
-    // Set `last_packet_number_` to one less that `num_calls` so that the packet
-    // will be fetched in the next InsertPacket() call.
-    last_packet_number_ = packet_cb_.num_calls() - 1;
-
-    StartThreads();
-  }
-
-  void RegisterCodec() override {
-    static_assert(kSampleRateHz == 16000, "test designed for iSAC 16 kHz");
-    audio_format_ = SdpAudioFormat("isac", kSampleRateHz, 1);
-    pac_size_ = 480;
-
-    // Register iSAC codec in ACM, effectively unregistering the PCM16B codec
-    // registered in AudioCodingModuleTestOldApi::SetUp();
-    acm_->SetReceiveCodecs({{kPayloadType, *audio_format_}});
-    acm_->SetEncoder(CreateBuiltinAudioEncoderFactory()->MakeAudioEncoder(
-        kPayloadType, *audio_format_, absl::nullopt));
-  }
-
-  void InsertPacket() override {
-    int num_calls = packet_cb_.num_calls();  // Store locally for thread safety.
-    if (num_calls > last_packet_number_) {
-      // Get the new payload out from the callback handler.
-      // Note that since we swap buffers here instead of directly inserting
-      // a pointer to the data in `packet_cb_`, we avoid locking the callback
-      // for the duration of the IncomingPacket() call.
-      packet_cb_.SwapBuffers(&last_payload_vec_);
-      ASSERT_GT(last_payload_vec_.size(), 0u);
-      rtp_utility_->Forward(&rtp_header_);
-      last_packet_number_ = num_calls;
-    }
-    ASSERT_GT(last_payload_vec_.size(), 0u);
-    ASSERT_EQ(0, acm_->IncomingPacket(&last_payload_vec_[0],
-                                      last_payload_vec_.size(), rtp_header_));
-  }
-
-  void InsertAudio() override {
-    // TODO(kwiberg): Use std::copy here. Might be complications because AFAICS
-    // this call confuses the number of samples with the number of bytes, and
-    // ends up copying only half of what it should.
-    memcpy(input_frame_.mutable_data(), audio_loop_.GetNextBlock().data(),
-           kNumSamples10ms);
-    AudioCodingModuleTestOldApi::InsertAudio();
-  }
-
-  // Override the verification function with no-op, since iSAC produces variable
-  // payload sizes.
-  void VerifyEncoding() override {}
-
-  // This method is the same as AudioCodingModuleMtTestOldApi::TestDone(), but
-  // here it is using the constants defined in this class (i.e., shorter test
-  // run).
-  bool TestDone() override {
-    if (packet_cb_.num_calls() > kNumPackets) {
-      MutexLock lock(&mutex_);
-      if (pull_audio_count_ > kNumPullCalls) {
-        // Both conditions for completion are met. End the test.
-        return true;
-      }
-    }
-    return false;
-  }
-
-  int last_packet_number_;
-  std::vector<uint8_t> last_payload_vec_;
-  test::AudioLoop audio_loop_;
-};
-
-#if defined(WEBRTC_IOS)
-#define MAYBE_DoTest DISABLED_DoTest
-#else
-#define MAYBE_DoTest DoTest
-#endif
-#if defined(WEBRTC_CODEC_ISAC) || defined(WEBRTC_CODEC_ISACFX)
-TEST_F(AcmIsacMtTestOldApi, MAYBE_DoTest) {
-  EXPECT_TRUE(RunTest());
-}
-#endif
-
-class AcmReRegisterIsacMtTestOldApi : public AudioCodingModuleTestOldApi {
- protected:
-  static const int kRegisterAfterNumPackets = 5;
-  static const int kNumPackets = 10;
-  static const int kPacketSizeMs = 30;
-  static const int kPacketSizeSamples = kPacketSizeMs * 16;
-
-  AcmReRegisterIsacMtTestOldApi()
-      : AudioCodingModuleTestOldApi(),
-        codec_registered_(false),
-        receive_packet_count_(0),
-        next_insert_packet_time_ms_(0),
-        fake_clock_(new SimulatedClock(0)) {
-    AudioEncoderIsacFloatImpl::Config config;
-    config.payload_type = kPayloadType;
-    isac_encoder_.reset(new AudioEncoderIsacFloatImpl(config));
-    clock_ = fake_clock_.get();
-  }
-
-  void SetUp() override {
-    AudioCodingModuleTestOldApi::SetUp();
-    // Set up input audio source to read from specified file, loop after 5
-    // seconds, and deliver blocks of 10 ms.
-    const std::string input_file_name =
-        webrtc::test::ResourcePath("audio_coding/speech_mono_16kHz", "pcm");
-    audio_loop_.Init(input_file_name, 5 * kSampleRateHz, kNumSamples10ms);
-    RegisterCodec();  // Must be called before the threads start below.
-    StartThreads();
-  }
-
-  void RegisterCodec() override {
-    // Register iSAC codec in ACM, effectively unregistering the PCM16B codec
-    // registered in AudioCodingModuleTestOldApi::SetUp();
-    // Only register the decoder for now. The encoder is registered later.
-    static_assert(kSampleRateHz == 16000, "test designed for iSAC 16 kHz");
-    acm_->SetReceiveCodecs({{kPayloadType, {"ISAC", kSampleRateHz, 1}}});
-  }
-
-  void StartThreads() {
-    quit_.store(false);
-    const auto attributes =
-        rtc::ThreadAttributes().SetPriority(rtc::ThreadPriority::kRealtime);
-    receive_thread_ = rtc::PlatformThread::SpawnJoinable(
-        [this] {
-          while (!quit_.load() && CbReceiveImpl()) {
-          }
-        },
-        "receive", attributes);
-    codec_registration_thread_ = rtc::PlatformThread::SpawnJoinable(
-        [this] {
-          while (!quit_.load()) {
-            CbCodecRegistrationImpl();
-          }
-        },
-        "codec_registration", attributes);
-  }
-
-  void TearDown() override {
-    AudioCodingModuleTestOldApi::TearDown();
-    quit_.store(true);
-    receive_thread_.Finalize();
-    codec_registration_thread_.Finalize();
-  }
-
-  bool RunTest() { return test_complete_.Wait(TimeDelta::Minutes(10)); }
-
-  bool CbReceiveImpl() {
-    SleepMs(1);
-    rtc::Buffer encoded;
-    AudioEncoder::EncodedInfo info;
-    {
-      MutexLock lock(&mutex_);
-      if (clock_->TimeInMilliseconds() < next_insert_packet_time_ms_) {
-        return true;
-      }
-      next_insert_packet_time_ms_ += kPacketSizeMs;
-      ++receive_packet_count_;
-
-      // Encode new frame.
-      uint32_t input_timestamp = rtp_header_.timestamp;
-      while (info.encoded_bytes == 0) {
-        info = isac_encoder_->Encode(input_timestamp,
-                                     audio_loop_.GetNextBlock(), &encoded);
-        input_timestamp += 160;  // 10 ms at 16 kHz.
-      }
-      EXPECT_EQ(rtp_header_.timestamp + kPacketSizeSamples, input_timestamp);
-      EXPECT_EQ(rtp_header_.timestamp, info.encoded_timestamp);
-      EXPECT_EQ(rtp_header_.payloadType, info.payload_type);
-    }
-    // Now we're not holding the crit sect when calling ACM.
-
-    // Insert into ACM.
-    EXPECT_EQ(0, acm_->IncomingPacket(encoded.data(), info.encoded_bytes,
-                                      rtp_header_));
-
-    // Pull audio.
-    for (int i = 0; i < rtc::CheckedDivExact(kPacketSizeMs, 10); ++i) {
-      AudioFrame audio_frame;
-      bool muted;
-      EXPECT_EQ(0, acm_->PlayoutData10Ms(-1 /* default output frequency */,
-                                         &audio_frame, &muted));
-      if (muted) {
-        ADD_FAILURE();
-        return false;
-      }
-      fake_clock_->AdvanceTimeMilliseconds(10);
-    }
-    rtp_utility_->Forward(&rtp_header_);
-    return true;
-  }
-
-  void CbCodecRegistrationImpl() {
-    SleepMs(1);
-    if (HasFatalFailure()) {
-      // End the test early if a fatal failure (ASSERT_*) has occurred.
-      test_complete_.Set();
-    }
-    MutexLock lock(&mutex_);
-    if (!codec_registered_ &&
-        receive_packet_count_ > kRegisterAfterNumPackets) {
-      // Register the iSAC encoder.
-      acm_->SetEncoder(CreateBuiltinAudioEncoderFactory()->MakeAudioEncoder(
-          kPayloadType, *audio_format_, absl::nullopt));
-      codec_registered_ = true;
-    }
-    if (codec_registered_ && receive_packet_count_ > kNumPackets) {
-      test_complete_.Set();
-    }
-  }
-
-  rtc::PlatformThread receive_thread_;
-  rtc::PlatformThread codec_registration_thread_;
-  // Used to force worker threads to stop looping.
-  std::atomic<bool> quit_;
-
-  rtc::Event test_complete_;
-  Mutex mutex_;
-  bool codec_registered_ RTC_GUARDED_BY(mutex_);
-  int receive_packet_count_ RTC_GUARDED_BY(mutex_);
-  int64_t next_insert_packet_time_ms_ RTC_GUARDED_BY(mutex_);
-  std::unique_ptr<AudioEncoderIsacFloatImpl> isac_encoder_;
-  std::unique_ptr<SimulatedClock> fake_clock_;
-  test::AudioLoop audio_loop_;
-};
-
-#if defined(WEBRTC_IOS)
-#define MAYBE_DoTest DISABLED_DoTest
-#else
-#define MAYBE_DoTest DoTest
-#endif
-#if defined(WEBRTC_CODEC_ISAC) || defined(WEBRTC_CODEC_ISACFX)
-TEST_F(AcmReRegisterIsacMtTestOldApi, MAYBE_DoTest) {
-  EXPECT_TRUE(RunTest());
-}
-#endif
-
 // Disabling all of these tests on iOS until file support has been added.
 // See https://code.google.com/p/webrtc/issues/detail?id=4752 for details.
 #if !defined(WEBRTC_IOS)
@@ -1025,38 +719,6 @@
 
 class AcmSenderBitExactnessNewApi : public AcmSenderBitExactnessOldApi {};
 
-// Run bit exactness tests only for release builds.
-#if (defined(WEBRTC_CODEC_ISAC) || defined(WEBRTC_CODEC_ISACFX)) && \
-    defined(NDEBUG) && defined(WEBRTC_LINUX) && defined(WEBRTC_ARCH_X86_64)
-TEST_F(AcmSenderBitExactnessOldApi, IsacWb30ms) {
-  ASSERT_NO_FATAL_FAILURE(SetUpTest("ISAC", 16000, 1, 103, 480, 480));
-  Run(/*audio_checksum_ref=*/"37ecdabad1698a857cf811e6d1fa91df",
-      /*payload_checksum_ref=*/"3c79f16f34218271f3dca4e2b1dfe1bb",
-      /*expected_packets=*/33,
-      /*expected_channels=*/test::AcmReceiveTestOldApi::kMonoOutput);
-}
-
-TEST_F(AcmSenderBitExactnessOldApi, IsacWb60ms) {
-  ASSERT_NO_FATAL_FAILURE(SetUpTest("ISAC", 16000, 1, 103, 960, 960));
-  Run(/*audio_checksum_ref=*/"0e9078d23454901496a88362ba0740c3",
-      /*payload_checksum_ref=*/"9e0a0ab743ad987b55b8e14802769c56",
-      /*expected_packets=*/16,
-      /*expected_channels=*/test::AcmReceiveTestOldApi::kMonoOutput);
-}
-#endif
-
-// Run bit exactness test only for release build.
-#if defined(WEBRTC_CODEC_ISAC) && defined(NDEBUG) && defined(WEBRTC_LINUX) && \
-    defined(WEBRTC_ARCH_X86_64)
-TEST_F(AcmSenderBitExactnessOldApi, IsacSwb30ms) {
-  ASSERT_NO_FATAL_FAILURE(SetUpTest("ISAC", 32000, 1, 104, 960, 960));
-  Run(/*audio_checksum_ref=*/"f4cf577f28a0dcbac33358b757518e0c",
-      /*payload_checksum_ref=*/"ce86106a93419aefb063097108ec94ab",
-      /*expected_packets=*/33,
-      /*expected_channels=*/test::AcmReceiveTestOldApi::kMonoOutput);
-}
-#endif
-
 TEST_F(AcmSenderBitExactnessOldApi, Pcm16_8000khz_10ms) {
   ASSERT_NO_FATAL_FAILURE(SetUpTest("L16", 8000, 1, 107, 80, 80));
   Run(/*audio_checksum_ref=*/"69118ed438ac76252d023e0463819471",