Allow mp3 audio codec for mpeg2ts containers in MSE

media/filters/stream_parser_factory.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "media/filters/stream_parser_factory.h"
 
 #include <stddef.h>
 
 #include "base/command_line.h"
 #include "base/macros.h"
@@ skipping 280 matching lines @@
   &kADTSCodecInfo,
   NULL
 };
 
 static StreamParser* BuildADTSParser(const std::vector<std::string>& codecs,
                                      const scoped_refptr<MediaLog>& media_log) {
   return new ADTSStreamParser();
 }
 
 #if BUILDFLAG(ENABLE_MSE_MPEG2TS_STREAM_PARSER)
+static const CodecInfo kMPEG2TS_MP3CodecInfo = {"mp3", CodecInfo::AUDIO, NULL,

[wolenetz, 2017/03/23 20:17:39]

NOT LGTM until resolved:
Is "mp3" standardized as a codec name for this mime type? For instance, in bug
661749, there is similar request for support for mp3 in mp4, with deliberation
on codec string (none being mp3, candidates are among "mp4a.6B", "mp4a.69", and
(less likely) "mp4a.40.some_x".

Though mp2ts is Chromecast-specific, we probably want to still try to maintain
in upstream at least some adherence to standard codec string names.

See MSE bytestream registry for mp2ts's specifying user agents *should* use
codec strings that conform to https://tools.ietf.org/html/rfc6381.

[servolk, 2017/03/23 23:24:59]

Ah, ok, as we've discussed offline, you are right - mp4a.6B and mp4a.69 seem to
be more standard-compliant codec ids for mp3. I've update the CL to use those
two codec ids instead of mp3.

+                                                CodecInfo::HISTOGRAM_MP3};
+
 static const CodecInfo* kVideoMP2TCodecs[] = {
-  &kH264AVC1CodecInfo,
-  &kH264AVC3CodecInfo,
-  &kMPEG4AACCodecInfo,
-  &kMPEG2AACLCCodecInfo,
-  NULL
-};
+    &kH264AVC1CodecInfo, &kH264AVC3CodecInfo,   &kMPEG2TS_MP3CodecInfo,
+    &kMPEG4AACCodecInfo, &kMPEG2AACLCCodecInfo, NULL};
 
 static StreamParser* BuildMP2TParser(const std::vector<std::string>& codecs,
                                      const scoped_refptr<MediaLog>& media_log) {
   bool has_sbr = false;
   for (size_t i = 0; i < codecs.size(); ++i) {
     std::string codec_id = codecs[i];
     if (base::MatchPattern(codec_id, kMPEG4AACCodecInfo.pattern)) {
       int audio_object_type = GetMP4AudioObjectType(codec_id, media_log);
       if (audio_object_type == kAACSBRObjectType ||
           audio_object_type == kAACPSObjectType) {
         has_sbr = true;
       }
     }
   }
 
   return new media::mp2t::Mp2tStreamParser(has_sbr);
 }
 #endif
 #endif
 
 static const SupportedTypeInfo kSupportedTypeInfo[] = {
     {"video/webm", &BuildWebMParser, kVideoWebMCodecs},
     {"audio/webm", &BuildWebMParser, kAudioWebMCodecs},
 #if BUILDFLAG(USE_PROPRIETARY_CODECS)
     {"audio/aac", &BuildADTSParser, kAudioADTSCodecs},
     {"audio/mpeg", &BuildMP3Parser, kAudioMP3Codecs},
     {"video/mp4", &BuildMP4Parser, kVideoMP4Codecs},
     {"audio/mp4", &BuildMP4Parser, kAudioMP4Codecs},
 #if BUILDFLAG(ENABLE_MSE_MPEG2TS_STREAM_PARSER)
     {"video/mp2t", &BuildMP2TParser, kVideoMP2TCodecs},

[wolenetz, 2017/03/23 21:35:52]

also nit/aside query: why no audio/mp2t?

[servolk, 2017/03/23 23:24:59]

TBH, I don't know, that code was added by damienv@ long time ago. I guess none
of the apps use the audio/mp2t type. Should we add it?

[wolenetz, 2017/03/24 17:34:25]

I was just curious. Since this is Chromecast specific, and apparently lack of
audio/mp2t hasn't been an issue there (nor need fixing in this particular CL if
it were an issue), probably ok not to add it.

[servolk, 2017/03/27 20:10:39]

Acknowledged.

 #endif
 #endif
 };
 
 // Verify that |codec_info| is supported on this platform.
 //
 // Returns true if |codec_info| is a valid audio/video codec and is allowed.
 // |audio_codecs| has |codec_info|.tag added to its list if |codec_info| is an
 // audio codec. |audio_codecs| may be NULL, in which case it is not updated.
 // |video_codecs| has |codec_info|.tag added to its list if |codec_info| is a
@@ skipping 134 matching lines @@
                                 CodecInfo::HISTOGRAM_MAX + 1);
     }
 
     stream_parser.reset(factory_function(codecs, media_log));
   }
 
   return stream_parser;
 }
 
 }  // namespace media