Write out MixPresentationTags in the OBU. Enforce content_language …

…is plausibly a ISO 639-2 code.

  - Add missing call to `MixPresentationTags::ValidateAndWrite` to actually write this out with the OBU.
  - Enforce `content_language` is a three-character code at write time (i.e. plausibly ISO 639-2).
    - At read time we will ignore this validation to be robust to bad bitstreams.
    - The restriction is loosely enforced, a strict one could check vs. the set of ISO 639-2.
    - ISO 639-2 is not to be confused with BCP-47 (see `annotations_language`).
    - Null terminator is automatically handled and guarded by `MixPresentationTagsWriteAndValidate/WritesContentLanguageTag`.
  - Update test vectors to use valid ISO 639-2 codes.
  - `encoder_main_lib_test`: For debugging, also write out the test file name when a test fails.

PiperOrigin-RevId: 665038667

iamf/cli/proto_to_obu/tests/mix_presentation_generator_test.cc

@@ -388,11 +388,11 @@ TEST(Generate, CopiesDuplicateContentLanguageTags) {
   auto* first_tag =
       mix_presentation.mutable_mix_presentation_tags()->add_tags();
   first_tag->set_tag_name("content_language");
-  first_tag->set_tag_value("en-us");
+  first_tag->set_tag_value("eng");
   auto* second_tag =
       mix_presentation.mutable_mix_presentation_tags()->add_tags();
   second_tag->set_tag_name("content_language");
-  second_tag->set_tag_value("en-uk");
+  second_tag->set_tag_value("kor");
 
   MixPresentationGenerator generator(mix_presentation_metadata);
 
@@ -405,10 +405,10 @@ TEST(Generate, CopiesDuplicateContentLanguageTags) {
   ASSERT_EQ(first_obu.mix_presentation_tags_->tags.size(), 2);
   EXPECT_EQ(first_obu.mix_presentation_tags_->tags[0].tag_name,
             "content_language");
-  EXPECT_EQ(first_obu.mix_presentation_tags_->tags[0].tag_value, "en-us");
+  EXPECT_EQ(first_obu.mix_presentation_tags_->tags[0].tag_value, "eng");
   EXPECT_EQ(first_obu.mix_presentation_tags_->tags[1].tag_name,
             "content_language");
-  EXPECT_EQ(first_obu.mix_presentation_tags_->tags[1].tag_value, "en-uk");
+  EXPECT_EQ(first_obu.mix_presentation_tags_->tags[1].tag_value, "kor");
 }
 
 TEST(Generate, IgnoresTagsWhenSetIncludeMixPresentationTagsIsFalse) {

iamf/cli/testdata/test_000704.textproto

@@ -173,7 +173,7 @@ mix_presentation_metadata {
     num_tags: 1
     tags: {
       tag_name: "content_language"
-      tag_value: "en-us"
+      tag_value: "eng"
     }
   }
 }

iamf/cli/testdata/test_000705.textproto

@@ -153,7 +153,7 @@ mix_presentation_metadata [
     mix_presentation_id: 42
     count_label: 1
     annotations_language: ["en-us"]
-    localized_presentation_annotations: ["Simulated US English Dialog (-0dB)."]
+    localized_presentation_annotations: ["Simulated English Dialog (-0dB)."]
     num_sub_mixes: 1
     sub_mixes {
       num_audio_elements: 2
@@ -221,15 +221,15 @@ mix_presentation_metadata [
       num_tags: 1
       tags: {
         tag_name: "content_language"
-        tag_value: "en-us"
+        tag_value: "eng"
       }
     }
   },
   {
     mix_presentation_id: 43
     count_label: 1
     annotations_language: ["en-us"]
-    localized_presentation_annotations: ["Simulated UK English Dialog (-5dB)."]
+    localized_presentation_annotations: ["Simulated Korean Dialog (-5dB)."]
     num_sub_mixes: 1
     sub_mixes {
       num_audio_elements: 2
@@ -297,15 +297,15 @@ mix_presentation_metadata [
       num_tags: 1
       tags: {
         tag_name: "content_language"
-        tag_value: "en-uk"
+        tag_value: "kor"
       }
     }
   },
   {
     mix_presentation_id: 44
     count_label: 1
     annotations_language: ["en-us"]
-    localized_presentation_annotations: ["Simulated AU English Dialog (-10dB)."]
+    localized_presentation_annotations: ["Simulated Esperanto Dialog (-10dB)."]
     num_sub_mixes: 1
     sub_mixes {
       num_audio_elements: 2
@@ -373,7 +373,7 @@ mix_presentation_metadata [
       num_tags: 1
       tags: {
         tag_name: "content_language"
-        tag_value: "en-au"
+        tag_value: "epo"
       }
     }
   }

iamf/cli/testdata/test_000706.textproto

@@ -148,7 +148,7 @@ mix_presentation_metadata [
     mix_presentation_id: 42
     count_label: 1
     annotations_language: ["en-us"]
-    localized_presentation_annotations: ["Simulated US English Dialog (-0dB)."]
+    localized_presentation_annotations: ["Simulated English Dialog (-0dB)."]
     num_sub_mixes: 1
     sub_mixes {
       num_audio_elements: 2
@@ -216,15 +216,15 @@ mix_presentation_metadata [
       num_tags: 1
       tags: {
         tag_name: "content_language"
-        tag_value: "en-us"
+        tag_value: "eng"
       }
     }
   },
   {
     mix_presentation_id: 43
     count_label: 1
     annotations_language: ["en-us"]
-    localized_presentation_annotations: ["Simulated UK English Dialog (-5dB)."]
+    localized_presentation_annotations: ["Simulated Korean Dialog (-5dB)."]
     num_sub_mixes: 1
     sub_mixes {
       num_audio_elements: 2
@@ -292,15 +292,15 @@ mix_presentation_metadata [
       num_tags: 1
       tags: {
         tag_name: "content_language"
-        tag_value: "en-uk"
+        tag_value: "kor"
       }
     }
   },
   {
     mix_presentation_id: 44
     count_label: 1
     annotations_language: ["en-us"]
-    localized_presentation_annotations: ["Simulated AU English Dialog (-10dB)."]
+    localized_presentation_annotations: ["Simulated Esperanto Dialog (-10dB)."]
     num_sub_mixes: 1
     sub_mixes {
       num_audio_elements: 2
@@ -368,7 +368,7 @@ mix_presentation_metadata [
       num_tags: 1
       tags: {
         tag_name: "content_language"
-        tag_value: "en-au"
+        tag_value: "epo"
       }
     }
   }

iamf/cli/testdata/test_000707.textproto

@@ -1188,7 +1188,7 @@ mix_presentation_metadata {
     num_tags: 1
     tags: {
       tag_name: "content_language"
-      tag_value: "en-us"
+      tag_value: "eng"
     }
   }
 }

iamf/cli/testdata/test_000710.textproto

@@ -1232,7 +1232,7 @@ mix_presentation_metadata [
       num_tags: 1
       tags: {
         tag_name: "content_language"
-        tag_value: "en-us"
+        tag_value: "eng"
       }
     }
   },
@@ -1308,7 +1308,7 @@ mix_presentation_metadata [
       num_tags: 1
       tags: {
         tag_name: "content_language"
-        tag_value: "en-us"
+        tag_value: "eng"
       }
     }
   }

iamf/cli/tests/encoder_main_lib_test.cc

@@ -219,9 +219,9 @@ TEST_P(TestVector, ValidateTestSuite) {
 
   // Check if the result matches the expected value in the protos.
   if (user_metadata.test_vector_metadata().is_valid()) {
-    EXPECT_THAT(result, IsOk());
+    EXPECT_THAT(result, IsOk()) << "File= " << test_case.textproto_filename;
   } else {
-    EXPECT_FALSE(result.ok());
+    EXPECT_FALSE(result.ok()) << " File= " << test_case.textproto_filename;
   }
 }
 

iamf/obu/mix_presentation.cc

@@ -20,6 +20,7 @@
 #include "absl/log/log.h"
 #include "absl/status/status.h"
 #include "absl/strings/str_cat.h"
+#include "absl/strings/string_view.h"
 #include "iamf/common/macros.h"
 #include "iamf/common/obu_util.h"
 #include "iamf/common/read_bit_buffer.h"
@@ -327,6 +328,20 @@ absl::Status MixPresentationSubMix::ReadAndValidate(const int32_t& count_label,
   return absl::OkStatus();
 }
 
+absl::Status ValidateCompliesWithIso639_2(absl::string_view string) {
+  if (string.size() == 3) {
+    // Consider any any three character string valid. A stricter
+    // implementation could check it actually is present in the list of valid
+    // ISO-639-2 code.
+    return absl::OkStatus();
+  } else {
+    return absl::InvalidArgumentError(absl::StrCat(
+        "Expected an ISO-639-2 code. ISO-639-2 codes should have three "
+        "characters. string= ",
+        string));
+  }
+}
+
 absl::Status MixPresentationTags::ValidateAndWrite(WriteBitBuffer& wb) const {
   RETURN_IF_NOT_OK(wb.WriteUnsignedLiteral(num_tags, 8));
   RETURN_IF_NOT_OK(ValidateVectorSizeEqual("tags", tags.size(), num_tags));
@@ -335,6 +350,8 @@ absl::Status MixPresentationTags::ValidateAndWrite(WriteBitBuffer& wb) const {
 
   for (const auto& tag : tags) {
     if (tag.tag_name == "content_language") {
+      RETURN_IF_NOT_OK(ValidateCompliesWithIso639_2(tag.tag_value));
+
       count_content_language_tag++;
     }
     RETURN_IF_NOT_OK(wb.WriteString(tag.tag_name));
@@ -474,6 +491,10 @@ absl::Status MixPresentationObu::ValidateAndWritePayload(
     RETURN_IF_NOT_OK(ValidateAndWriteSubMix(count_label_, sub_mix, wb));
   }
 
+  if (mix_presentation_tags_.has_value()) {
+    RETURN_IF_NOT_OK(mix_presentation_tags_->ValidateAndWrite(wb));
+  }
+
   return absl::OkStatus();
 }
 

iamf/obu/tests/BUILD

@@ -131,6 +131,7 @@ cc_test(
         "//iamf/common:bit_buffer_util",
         "//iamf/common:read_bit_buffer",
         "//iamf/common:write_bit_buffer",
+        "//iamf/common/tests:test_utils",
         "//iamf/obu:leb128",
         "//iamf/obu:mix_presentation",
         "//iamf/obu:obu_header",

iamf/obu/tests/mix_presentation_test.cc

@@ -25,6 +25,7 @@
 #include "iamf/cli/leb_generator.h"
 #include "iamf/common/bit_buffer_util.h"
 #include "iamf/common/read_bit_buffer.h"
+#include "iamf/common/tests/test_utils.h"
 #include "iamf/common/write_bit_buffer.h"
 #include "iamf/obu/leb128.h"
 #include "iamf/obu/obu_header.h"
@@ -105,7 +106,8 @@ class MixPresentationObuTest : public ObuTestBase, public testing::Test {
                                         .digital_peak = 19,
                                         .true_peak = 20}}}}}),
         dynamic_sub_mix_args_({{.element_mix_gain_subblocks = {{}},
-                                .output_mix_gain_subblocks = {}}}) {
+                                .output_mix_gain_subblocks = {}}}),
+        mix_presentation_tags_(std::nullopt) {
     MixGainParamDefinition element_mix_gain;
     element_mix_gain.parameter_id_ = 12;
     element_mix_gain.parameter_rate_ = 13;
@@ -147,6 +149,8 @@ class MixPresentationObuTest : public ObuTestBase, public testing::Test {
   // Length `num_sub_mixes`.
   std::vector<DynamicSubMixArguments> dynamic_sub_mix_args_;
 
+  std::optional<MixPresentationTags> mix_presentation_tags_;
+
  private:
   // Copies over data into the output argument `obu->sub_mix[i]`.
   void InitSubMixDynamicMemory(int i) {
@@ -787,6 +791,40 @@ TEST_F(MixPresentationObuTest, ValidateAndWriteFailsWithInvalidMissingStero) {
   EXPECT_FALSE(obu_->ValidateAndWriteObu(unused_wb).ok());
 }
 
+TEST_F(MixPresentationObuTest, WritesMixPresentionTags) {
+  expected_header_ = {kObuIaMixPresentation << 3, 58};
+  expected_payload_ = {
+      // Start Mix OBU.
+      10, 1, 'e', 'n', '-', 'u', 's', '\0', 'M', 'i', 'x', ' ', '1', '\0', 1,
+      // Start Submix 1
+      1, 11, 'S', 'u', 'b', 'm', 'i', 'x', ' ', '1', '\0',
+      // Start RenderingConfig.
+      RenderingConfig::kHeadphonesRenderingModeStereo << 6, 0,
+      // End RenderingConfig.
+      12, 13, 0x80, 0, 14, 15, 16, 0x80, 0, 17, 1,
+      // Start Layout 1 (of Submix 1).
+      (Layout::kLayoutTypeLoudspeakersSsConvention << 6) |
+          LoudspeakersSsConventionLayout::kSoundSystemA_0_2_0,
+      LoudnessInfo::kTruePeak, 0, 18, 0, 19, 0, 20,
+      // Start Mix Presentation Tags.
+      // `num_tags`.
+      1,
+      // `tag_name[0]`.
+      't', 'a', 'g', '\0',
+      // `tag_value[0]`.
+      'v', 'a', 'l', 'u', 'e', '\0',
+      // End Mix OBU.
+  };
+  InitExpectOk();
+  obu_->mix_presentation_tags_ =
+      MixPresentationTags{.num_tags = 1, .tags = {{"tag", "value"}}};
+
+  WriteBitBuffer wb(1024);
+  EXPECT_THAT(obu_->ValidateAndWriteObu(wb), IsOk());
+
+  ValidateObuWriteResults(wb, expected_header_, expected_payload_);
+}
+
 class GetNumChannelsFromLayoutTest : public testing::Test {
  public:
   GetNumChannelsFromLayoutTest()
@@ -1329,15 +1367,15 @@ TEST(MixPresentationTagsWriteAndValidate, WritesWithZeroTags) {
 TEST(MixPresentationTagsWriteAndValidate, WritesContentLanguageTag) {
   constexpr uint8_t kOneTag = 1;
   const MixPresentationTags kMixPresentationTagsWithContentLanguageTag = {
-      .num_tags = kOneTag, .tags = {{"content_language", "en-us"}}};
+      .num_tags = kOneTag, .tags = {{"content_language", "eng"}}};
   const std::vector<uint8_t> kExpectedBuffer = {
       // `num_tags`.
       kOneTag,
       // `tag_name[0]`.
       'c', 'o', 'n', 't', 'e', 'n', 't', '_', 'l', 'a', 'n', 'g', 'u', 'a', 'g',
       'e', '\0',
       // `tag_value[0]`.
-      'e', 'n', '-', 'u', 's', '\0'};
+      'e', 'n', 'g', '\0'};
   WriteBitBuffer wb(1024);
 
   EXPECT_THAT(kMixPresentationTagsWithContentLanguageTag.ValidateAndWrite(wb),
@@ -1346,6 +1384,18 @@ TEST(MixPresentationTagsWriteAndValidate, WritesContentLanguageTag) {
   EXPECT_EQ(wb.bit_buffer(), kExpectedBuffer);
 }
 
+TEST(MixPresentationTagsWriteAndValidate,
+     InvalidWhenContentLanguageTagNotThreeCharacters) {
+  constexpr uint8_t kOneTag = 1;
+  const MixPresentationTags kMixPresentationTagsWithContentLanguageTag = {
+      .num_tags = kOneTag, .tags = {{"content_language", "en-us"}}};
+
+  WriteBitBuffer wb(0);
+
+  EXPECT_FALSE(
+      kMixPresentationTagsWithContentLanguageTag.ValidateAndWrite(wb).ok());
+}
+
 TEST(MixPresentationTagsWriteAndValidate, WritesArbitraryTags) {
   constexpr uint8_t kNumTags = 1;
   const MixPresentationTags kMixPresentationTagsWithArbitraryTag = {
@@ -1391,8 +1441,7 @@ TEST(MixPresentationTagsWriteAndValidate, InvalidForDuplicateContentIdTag) {
   const MixPresentationTags
       kMixPresentationTagsWithDuplicateContentLanguageTag = {
           .num_tags = kTwoTags,
-          .tags = {{"content_language", "en-us"},
-                   {"content_language", "en-gb"}}};
+          .tags = {{"content_language", "eng"}, {"content_language", "kor"}}};
 
   WriteBitBuffer wb(1024);