WebM support for new multipart VP9 string.

media/base/video_codecs.cc

Index: media/base/video_codecs.cc
diff --git a/media/base/video_codecs.cc b/media/base/video_codecs.cc
index eb7daa2c21be0f2127073ebab00f74b28c7ee2e9..027bfd9218e7eb2f9e113101f4fbffbcb174aaed 100644
--- a/media/base/video_codecs.cc
+++ b/media/base/video_codecs.cc
@@ -86,21 +86,28 @@ std::string GetProfileName(VideoCodecProfile profile) {
 
 bool ParseNewStyleVp9CodecID(const std::string& codec_id,
                              VideoCodecProfile* profile,
-                             uint8_t* level_idc) {
+                             uint8_t* level_idc,
+                             gfx::ColorSpace::TransferID* eotf) {
+  LOG(ERROR) << __func__ << " 0";

[servolk, 2017/03/02 18:56:36]

Nit: don't forget to remove this debug logging.

[chcunningham, 2017/03/02 23:13:08]

Acknowledged.

+
+  // Initialize optional fields to their defaults.
+  *eotf = gfx::ColorSpace::TransferID::BT709;
+
   std::vector<std::string> fields = base::SplitString(
       codec_id, ".", base::KEEP_WHITESPACE, base::SPLIT_WANT_ALL);
 
-  // TODO(kqyang): The spec specifies 8 fields. We do not allow missing or extra
-  // fields. See crbug.com/667834.
-  if (fields.size() != 8)
+  // First four fields are mandatory. No more than 9 fields are expected.
+  if (fields.size() < 4 || fields.size() > 9)
     return false;
 
   if (fields[0] != "vp09")
     return false;
 
+  LOG(ERROR) << __func__ << " 1";
+
   std::vector<int> values;
   for (size_t i = 1; i < fields.size(); ++i) {
-    // Missing value is not allowed.
+    // Missing value is not allowed. ------------------------------------------ is still this right?
     if (fields[i] == "")
       return false;
     int value;
@@ -111,6 +118,7 @@ bool ParseNewStyleVp9CodecID(const std::string& codec_id,
     values.push_back(value);
   }
 
+  LOG(ERROR) << __func__ << " 2";
   const int profile_idc = values[0];
   switch (profile_idc) {
     case 0:
@@ -129,6 +137,7 @@ bool ParseNewStyleVp9CodecID(const std::string& codec_id,
       return false;
   }
 
+  LOG(ERROR) << __func__ << " 3";
   *level_idc = values[1];
   // TODO(kqyang): Check if |level_idc| is valid. See crbug.com/667834.
 
@@ -136,22 +145,62 @@ bool ParseNewStyleVp9CodecID(const std::string& codec_id,
   if (bit_depth != 8 && bit_depth != 10 && bit_depth != 12)
     return false;
 
+  if (values.size() < 4)
+    return true;
+  LOG(ERROR) << __func__ << " 4";
   const int color_space = values[3];
-  if (color_space > 7)
+  if (color_space > 9)
     return false;
 
-  const int chroma_subsampling = values[4];
-  if (chroma_subsampling > 3)
-    return false;
+  LOG(ERROR) << __func__ << " 5";
+  if (values.size() < 5)
+    return true;
+  const int transfer_function = values[4];
+  switch (transfer_function) {
+    case 0:

[servolk, 2017/03/02 18:56:36]

Are those values taken from
https://docs.google.com/document/d/16kiRszCusuK-ph_3h2HKvPgk_zLuHiM1NUfdyIH8_...
?
Looks like that's still in the draft stage, in particular there is this comment
thread
https://docs.google.com/a/google.com/document/d/16kiRszCusuK-ph_3h2HKvPgk_zLu...
which indicates these values are going to be changed to match ISO spec. Perhaps
we should wait until the VP9 codec id format is more standardized, before we add
this code?

[chcunningham, 2017/03/02 23:13:08]

Right, these values are taken from a draft which is expected to be replaced by
values from ISO/IEC 23001-8:2016. I'll buy that spec and update accordingly.

+      // "0" bucket denotes one of:
+      //   Rec. ITU-R BT.709-6
+      //   Rec. ITU-R BT.601-7 525 or 625
+      //   Rec. ITU-R BT.2020.
+      // These are all non-HDR, so just grab 709 since they're all treated
+      // the same from a capabilities standpoint.
+      *eotf = gfx::ColorSpace::TransferID::BT709;
+      break;
+    case 1:
+      *eotf = gfx::ColorSpace::TransferID::SMPTEST2084;
+      break;
+    case 2:
+      *eotf = gfx::ColorSpace::TransferID::ARIB_STD_B67;  // AKA "HLG"
+      break;
+    default:
+      *eotf = gfx::ColorSpace::TransferID::INVALID;
+      DVLOG(4) << __func__ << ": invalid transfer function id ("
+               << transfer_function << ")";
+      return false;
+  }
 
-  const int transfer_function = values[5];
-  if (transfer_function > 1)
+  LOG(ERROR) << __func__ << " 6";
+  if (values.size() < 6)
+    return true;
+  const int matrix_coefficients = values[5];
+  if (matrix_coefficients < 0)
     return false;
 
+  LOG(ERROR) << __func__ << " 7";
+  if (values.size() < 7)
+    return true;
   const int video_full_range_flag = values[6];
-  if (video_full_range_flag > 1)
+  if (video_full_range_flag < 0 || video_full_range_flag > 1)
     return false;
 
+  LOG(ERROR) << __func__ << " 8";
+  if (values.size() < 8)
+    return true;
+  const int chroma_subsampling = values[7];
+  if (chroma_subsampling < 0 || chroma_subsampling > 3)
+    return false;
+
+  LOG(ERROR) << __func__ << " 9";
   return true;
 }
 
@@ -424,11 +473,14 @@ VideoCodec StringToVideoCodec(const std::string& codec_id) {
       codec_id, ".", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
   if (elem.empty())
     return kUnknownVideoCodec;
+
   VideoCodecProfile profile = VIDEO_CODEC_PROFILE_UNKNOWN;
   uint8_t level = 0;
+  gfx::ColorSpace::TransferID eotf = gfx::ColorSpace::TransferID::INVALID;
+
   if (codec_id == "vp8" || codec_id == "vp8.0")
     return kCodecVP8;
-  if (ParseNewStyleVp9CodecID(codec_id, &profile, &level) ||
+  if (ParseNewStyleVp9CodecID(codec_id, &profile, &level, &eotf) ||
       ParseLegacyVp9CodecID(codec_id, &profile, &level)) {
     return kCodecVP9;
   }