Implemented HEVC video demuxing and parsing

media/base/mime_util.cc

 // Copyright 2012 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 <map>
 
 #include "base/containers/hash_tables.h"
 #include "base/lazy_instance.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_split.h"
@@ skipping 18 matching lines @@
     MPEG2_AAC_MAIN,
     MPEG2_AAC_SSR,
     MPEG4_AAC_LC,
     MPEG4_AAC_SBR_v1,
     MPEG4_AAC_SBR_PS_v2,
     VORBIS,
     OPUS,
     H264_BASELINE,
     H264_MAIN,
     H264_HIGH,
+    HEVC_MAIN,
     VP8,
     VP9,
     THEORA
   };
 
   bool IsSupportedMediaMimeType(const std::string& mime_type) const;
 
   bool AreSupportedMediaCodecs(const std::vector<std::string>& codecs) const;
 
   void ParseCodecString(const std::string& codecs,
@@ skipping 143 matching lines @@
     case MimeUtil::MPEG4_AAC_LC:
     case MimeUtil::MPEG4_AAC_SBR_v1:
     case MimeUtil::MPEG4_AAC_SBR_PS_v2:
     case MimeUtil::H264_BASELINE:
     case MimeUtil::H264_MAIN:
     case MimeUtil::H264_HIGH:
     case MimeUtil::VP8:
     case MimeUtil::VORBIS:
       return true;
 
+    case MimeUtil::HEVC_MAIN:
+#if defined(ENABLE_HEVC_DEMUXING)
+      // HEVC/H.265 is supported in Lollipop+ (API Level 21), according to
+      // http://developer.android.com/reference/android/media/MediaFormat.html
+      return base::android::BuildInfo::GetInstance()->sdk_int() >= 21;
+#else
+      return false;
+#endif
+
     case MimeUtil::MPEG2_AAC_LC:
     case MimeUtil::MPEG2_AAC_MAIN:
     case MimeUtil::MPEG2_AAC_SSR:
       // MPEG-2 variants of AAC are not supported on Android.
       return false;
 
     case MimeUtil::VP9:
       // VP9 is supported only in KitKat+ (API Level 19).
       return base::android::BuildInfo::GetInstance()->sdk_int() >= 19;
 
@@ skipping 34 matching lines @@
     "mp4a.66,mp4a.67,mp4a.68,mp4a.69,mp4a.6B,mp4a.40.2,mp4a.40.02,mp4a.40.5,"
     "mp4a.40.05,mp4a.40.29";
 static const char kMP4VideoCodecsExpression[] =
     // This is not a complete list of supported avc1 codecs. It is simply used
     // to register support for the corresponding Codec enum. Instead of using
     // strings in these three arrays, we should use the Codec enum values.
     // This will avoid confusion and unnecessary parsing at runtime.
     // kUnambiguousCodecStringMap/kAmbiguousCodecStringMap should be the only
     // mapping from strings to codecs. See crbug.com/461009.
     "avc1.42E00A,avc1.4D400A,avc1.64000A,"
+#if defined(ENABLE_HEVC_DEMUXING)
+    // Any valid unambiguous HEVC codec id will work here, since these strings
+    // are parsed and mapped to MimeUtil::Codec enum values.
+    "hev1.1.6.L93.B0,"
+#endif
     "mp4a.66,mp4a.67,mp4a.68,mp4a.69,mp4a.6B,mp4a.40.2,mp4a.40.02,mp4a.40.5,"
     "mp4a.40.05,mp4a.40.29";
 
 // These containers are also included in
 // common_media_types/proprietary_media_types. See crbug.com/461012.
 static const MediaFormatStrict format_codec_mappings[] = {
     {"video/webm", "opus,vorbis,vp8,vp8.0,vp9,vp9.0"},
     {"audio/webm", "opus,vorbis"},
     {"audio/wav", "1"},
     {"audio/x-wav", "1"},
@@ skipping 289 matching lines @@
     *codec = MimeUtil::H264_BASELINE;
     *is_ambiguous = true;
     return true;
   }
 
   *is_ambiguous =
       !IsValidH264Level(base::StringToUpperASCII(codec_id.substr(9)));
   return true;
 }
 
+#if defined(ENABLE_HEVC_DEMUXING)
+// HEVC/H.265 is a new video codec, evolution of the H.264/AVC standard. ISO/IEC

[ddorwin, 2015/06/20 00:28:21]

I don't think the first sentence is relevant.

[servolk, 2015/06/25 23:02:09]

Done.

+// FDIS 14496-15 standard section E.3 describes the syntax of codec ids
+// reserved for HEVC. According to that spec HEVC codec id must start with
+// either "hev1." or "hvc1.". We don't yet support full parsing of HEVC codec
+// ids, but since no other codec id starts with those string we'll just treat
+// any string starting with "hev1." or "hvc1." as valid HEVC codec ids.
+// crbug.com/482761
+static bool ParseHEVCCodecID(const std::string& codec_id,
+                             MimeUtil::Codec* codec,
+                             bool* is_ambiguous) {
+  if (base::StartsWithASCII(codec_id, "hev1.", true) ||
+      base::StartsWithASCII(codec_id, "hvc1.", true)) {
+    *codec = MimeUtil::HEVC_MAIN;
+    *is_ambiguous = true;

[ddorwin, 2015/06/20 00:28:21]

This line should be below the TODO, since it would be affected.

Also, you could just do the following at 601.
*is_ambiguous = codec_id != "hev1.1.6.L93.B0" && codec_id != "hvc1.1.6.L93.B0".

If you really want to keep the two values separate, you might break the TODO up
into two separate comments - one that this is false until we implement it and
another that is the workaround.

[servolk, 2015/06/25 23:02:09]

Done.

+
+    // TODO(servolk): Full HEVC codec id parsing is not implemented yet (see
+    // crbug.com/482761), but we need to recognize at least one valid
+    // unambiguous HEVC codec id, which is added kMP4VideoCodecsExpression. We
+    // need it to be unambiguous to avoid DCHECK at line 405. We also use these
+    // in unit tests. Remove this workaround after crbug.com/482761 is fixed.
+    if (codec_id == "hev1.1.6.L93.B0" || codec_id == "hvc1.1.6.L93.B0") {
+      *is_ambiguous = false;
+    }
+
+    return true;
+  }
+
+  return false;
+}
+#endif
+
 bool MimeUtil::StringToCodec(const std::string& codec_id,
                              Codec* codec,
                              bool* is_ambiguous) const {
   StringToCodecMappings::const_iterator itr =
       string_to_codec_map_.find(codec_id);
   if (itr != string_to_codec_map_.end()) {
     *codec = itr->second.codec;
     *is_ambiguous = itr->second.is_ambiguous;
     return true;
   }
 
   // If |codec_id| is not in |string_to_codec_map_|, then we assume that it is
-  // an H.264 codec ID because currently those are the only ones that can't be
-  // stored in the |string_to_codec_map_| and require parsing.
+  // either H.264 or HEVC/H.265 codec ID because currently those are the only
+  // ones that are not added to the |string_to_codec_map_| and require parsing.
+#if defined(ENABLE_HEVC_DEMUXING)
+  if (ParseHEVCCodecID(codec_id, codec, is_ambiguous)) {
+    return true;
+  }
+#endif
   return ParseH264CodecID(codec_id, codec, is_ambiguous);
 }
 
 bool MimeUtil::IsCodecSupported(Codec codec) const {
   DCHECK_NE(codec, INVALID_CODEC);
 
 #if defined(OS_ANDROID)
   if (!IsCodecSupportedOnAndroid(codec))
     return false;
 #endif
 
   return allow_proprietary_codecs_ || !IsCodecProprietary(codec);
 }
 
 bool MimeUtil::IsCodecProprietary(Codec codec) const {
   switch (codec) {
     case INVALID_CODEC:
     case MP3:
     case MPEG2_AAC_LC:
     case MPEG2_AAC_MAIN:
     case MPEG2_AAC_SSR:
     case MPEG4_AAC_LC:
     case MPEG4_AAC_SBR_v1:
     case MPEG4_AAC_SBR_PS_v2:
     case H264_BASELINE:
     case H264_MAIN:
     case H264_HIGH:
+    case HEVC_MAIN:
       return true;
 
     case PCM:
     case VORBIS:
     case OPUS:
     case VP8:
     case VP9:
     case THEORA:
       return false;
   }
@@ skipping 44 matching lines @@
                       std::vector<std::string>* codecs_out,
                       const bool strip) {
   g_media_mime_util.Get().ParseCodecString(codecs, codecs_out, strip);
 }
 
 void RemoveProprietaryMediaTypesAndCodecsForTests() {
   g_media_mime_util.Get().RemoveProprietaryMediaTypesAndCodecsForTests();
 }
 
 }  // namespace media