MP4 support for Common Encryption 'cbcs' scheme.

media/formats/mp4/box_definitions.h

Index: media/formats/mp4/box_definitions.h
diff --git a/media/formats/mp4/box_definitions.h b/media/formats/mp4/box_definitions.h
index 01138801bea9d590af1327fe37527646fb0c8fce..8c2f2832f7c95e3116a49c0cb28962c656ef8ce3 100644
--- a/media/formats/mp4/box_definitions.h
+++ b/media/formats/mp4/box_definitions.h
@@ -20,6 +20,7 @@
 #include "media/formats/mp4/avc.h"
 #include "media/formats/mp4/box_reader.h"
 #include "media/formats/mp4/fourccs.h"
+#include "media/media_features.h"
 
 namespace media {
 namespace mp4 {
@@ -129,6 +130,12 @@ struct MEDIA_EXPORT TrackEncryption : Box {
   bool is_encrypted;
   uint8_t default_iv_size;
   std::vector<uint8_t> default_kid;
+#if BUILDFLAG(ENABLE_CBCS_ENCRYPTION_SCHEME)
+  uint8_t default_crypt_byte_block;

[ddorwin, 2016/06/17 23:32:40]

Is "crypt" a common term in the spec? If not, use "encrypted" - abbreviations
are discouraged unless common.

[dougsteed, 2016/10/10 18:18:01]

yes, this is the term used in the spec.

+  uint8_t default_skip_byte_block;

[ddorwin, 2016/06/17 23:32:40]

Is this a count? If so, specify that because it's not obvious. Same above.

[dougsteed, 2016/10/10 18:18:01]

I used the exact term in the spec that names this field.

+  uint8_t default_constant_iv_size;
+  uint8_t default_constant_iv[16];
+#endif
 };
 
 struct MEDIA_EXPORT SchemeInfo : Box {
@@ -143,6 +150,8 @@ struct MEDIA_EXPORT ProtectionSchemeInfo : Box {
   OriginalFormat format;
   SchemeType type;
   SchemeInfo info;
+
+  bool HasSupportedScheme() const;
 };
 
 struct MEDIA_EXPORT MovieHeader : Box {
@@ -282,10 +291,17 @@ struct MEDIA_EXPORT CencSampleEncryptionInfoEntry {
   CencSampleEncryptionInfoEntry();
   CencSampleEncryptionInfoEntry(const CencSampleEncryptionInfoEntry& other);
   ~CencSampleEncryptionInfoEntry();
+  bool Parse(BoxReader* reader);
 
   bool is_encrypted;
   uint8_t iv_size;
   std::vector<uint8_t> key_id;
+#if BUILDFLAG(ENABLE_CBCS_ENCRYPTION_SCHEME)
+  uint8_t crypt_byte_block;

[ddorwin, 2016/06/17 23:32:40]

ditto on names

[dougsteed, 2016/10/10 18:18:01]

ditto. This is the actual name for the field in the standard.

+  uint8_t skip_byte_block;
+  uint8_t constant_iv_size;
+  uint8_t constant_iv[16];
+#endif
 };
 
 struct MEDIA_EXPORT SampleGroupDescription : Box {  // 'sgpd'.