Updated AAC:Parse() to emit better error logs.

media/formats/mp4/aac.cc

Index: media/formats/mp4/aac.cc
diff --git a/media/formats/mp4/aac.cc b/media/formats/mp4/aac.cc
index 9aa749ca310cffe9eb0520c8c2c6395da439c4f0..665e90cb487cd679f9a71cdab9b9319d777310e4 100644
--- a/media/formats/mp4/aac.cc
+++ b/media/formats/mp4/aac.cc
@@ -58,9 +58,6 @@ bool AAC::Parse(const std::vector<uint8>& data,
     RCHECK(reader.ReadBits(5, &profile_));
   }
 
-  MEDIA_LOG(INFO, media_log) << "Audio codec: mp4a.40." << std::hex
-                             << static_cast<int>(profile_);
-
   RCHECK(SkipDecoderGASpecificConfig(&reader));
   RCHECK(SkipErrorSpecificConfig());
 
@@ -96,12 +93,26 @@ bool AAC::Parse(const std::vector<uint8>& data,
   }
 
   if (frequency_ == 0) {
-    RCHECK(frequency_index_ < kADTSFrequencyTableSize);
+    if (frequency_index_ >= kADTSFrequencyTableSize) {
+      MEDIA_LOG(ERROR, media_log)
+          << "Unsupported Sampling Frequency Index with value 0x"
+          << std::hex << static_cast<int>(frequency_index_)
+          << ". Please see ISO 14496 Part 3 Table 1.16 "
+          << "for supported Sampling Frequencies.";
+      return false;
+    }
     frequency_ = kADTSFrequencyTable[frequency_index_];
   }
 
   if (extension_frequency_ == 0 && extension_frequency_index != 0xff) {
-    RCHECK(extension_frequency_index < kADTSFrequencyTableSize);
+    if (extension_frequency_index >= kADTSFrequencyTableSize) {
+      MEDIA_LOG(ERROR, media_log)
+          << "Unsupported Sampling Frequency Index with value 0x"

[wolenetz, 2015/08/28 23:29:35]

ISTM text like "Unsupported Extension Sampling Frequency Index..." would be more
specifically correct in this particular log message. Am I mistaken?

[msu.koo, 2015/08/29 09:36:51]

Done.

+          << std::hex << static_cast<int>(frequency_index_)
+          << ". Please see ISO 14496 Part 3 Table 1.16 "
+          << "for supported Sampling Frequencies.";
+      return false;
+    }
     extension_frequency_ = kADTSFrequencyTable[extension_frequency_index];
   }
 
@@ -109,12 +120,37 @@ bool AAC::Parse(const std::vector<uint8>& data,
   if (ps_present && channel_config_ == 1) {
     channel_layout_ = CHANNEL_LAYOUT_STEREO;
   } else {
-    RCHECK(channel_config_ < kADTSChannelLayoutTableSize);
+    if (channel_config_ >= kADTSChannelLayoutTableSize) {
+      MEDIA_LOG(ERROR, media_log)
+          << "Unsupported Channel Configuration with value "
+          << static_cast<int>(channel_config_) << "."

[wolenetz, 2015/08/28 23:29:35]

nit: s/"."/". "/

[msu.koo, 2015/08/29 09:36:51]

Done.

+          << "Please see ISO 14496 Part 3 Table 1.17 "
+          << "for supported Channel Configurations.";
+      return false;
+    }
     channel_layout_ = kADTSChannelLayoutTable[channel_config_];
   }
 
-  return frequency_ != 0 && channel_layout_ != CHANNEL_LAYOUT_NONE &&
-         profile_ >= 1 && profile_ <= 4;
+  RCHECK_MEDIA_LOGGED(frequency_ != 0, media_log,
+                      "Audio frequency is invalid with value 0.");
+  RCHECK_MEDIA_LOGGED(channel_layout_ != CHANNEL_LAYOUT_NONE, media_log,
+                      "Undefined Audio Channel layout with value "
+                      "CHANNEL_LAYOUT_NONE.");
+  if (profile_ < 1 || profile_ > 4) {

[wolenetz, 2015/08/28 23:29:35]

side note: Looking over this logic, I've filed crbug 526314 since
SBR-in-mimetype logic, above, is confusing to me when profile 5 is "SBR".
There's probably a good reason why the logic is the way it is, but I'd like to
understand better why (hence that bug to track follow-up).

[msu.koo, 2015/08/29 09:36:51]

OK, I also agree with you opinion. More investigation is required whether we can
support Audio Object type 5. Let's see on your new filed  issue.

+    MEDIA_LOG(ERROR, media_log)
+        << "Audio codec: mp4a.40." << static_cast<int>(profile_)
+        << " is not supported."

[wolenetz, 2015/08/28 23:29:35]

nit ditto: s/"."/". "/

[msu.koo, 2015/08/29 09:36:51]

Done.

+        <<"Please see ISO 14496 Part 3 Table 1.3 "
+        << "for Audio Profile Definitions.";
+    return false;
+  }
+
+  MEDIA_LOG(INFO, media_log)
+      << "Audio codec: mp4a.40." << static_cast<int>(profile_)
+      << ", Sampling frequency: " << frequency_ << "Hz"
+      << ", Extension Sampling frequency: " << extension_frequency_ << "Hz"
+      << ", Channel_layout: " << channel_layout_;

[wolenetz, 2015/08/28 23:29:35]

nit: s/Channel_layout/Channel layout/

[msu.koo, 2015/08/29 09:36:51]

Done.

+  return true;
 }
 
 int AAC::GetOutputSamplesPerSecond(bool sbr_in_mimetype) const {