Support subsample encryption in WebM container |
||||||
Issue descriptionThe rationale for this is to facilitate the implementation of secure video pipelines by leaving relevant metadata portions of the media samples in the clear, and available for processing before sample decryption. The EncryptedBlock format can be augmented by setting a new “partitioned” bit, which is allocated out of the currently reserved RSV bits of the signaling byte field of the header. If this bit is set, then the EncryptedBlock header is extended to include an 8-bit integer indicating the number of sample partitions, and a series of 32-bit integers indicating the byte offsets of such partitions. See this document https://docs.google.com/document/d/1ceGrHxA5nDeXBtghTGBM0L0vg8mrDcwX8aHJtoT15FQ/edit# for the details.
,
Jul 21 2016
,
Aug 2 2016
What is the the status of the spec? How stable is it? Can we make it public? When will it be more formalized along with the existing WebM encryption spec?
,
Aug 2 2016
,
Aug 2 2016
@tinskip, @fgalligan, any comment to @ddorwin's question?
,
Aug 2 2016
Re #3: Spec is very much a draft, but we need to be able to test the content. We won't check in until the fate of the spec has been determined.
,
Aug 2 2016
@tinskip: do you have an expected timescale for spec changes? I need to decide whether to check what we have here into Chromecast's build for our next release or whether to wait for this to be checked into chromium.
,
Aug 3 2016
fgalligan@ is responsible for the WebM spec, and he's out for a couple weeks. I'll ping him when he's back (unless he reads this first).
,
Aug 3 2016
Ok. Waiting 2 weeks means missing a release, which means Cast TVs won't be able to get the feature till mid-Nov. Happy to go either way, depends on priority of this vs risk of spec changing. Let me know what you think.
,
Aug 18 2016
@tinskip, @fgalligan, how is the spec going? Can we consider it stable now? (http://www.webmproject.org/docs/webm-encryption/ is not updated yet)
,
Sep 12 2016
Noticed that the WebM subsample encryption spec has been published in http://wiki.webmproject.org/encryption/webm-subsample-encryption. @fgalligan, is there any plan to update http://www.webmproject.org/docs/webm-encryption/ as well?
,
Sep 14 2016
The following revision refers to this bug: https://chromium.googlesource.com/chromium/src.git/+/f35464f359937e4f2ad362cd7919223b012dfd3f commit f35464f359937e4f2ad362cd7919223b012dfd3f Author: kqyang <kqyang@chromium.org> Date: Wed Sep 14 22:50:41 2016 Implement WebM subsample support according to the specification at http://wiki.webmproject.org/encryption/webm-subsample-encryption. BUG= 630344 Review-Url: https://codereview.chromium.org/2174533002 Cr-Commit-Position: refs/heads/master@{#418705} [modify] https://crrev.com/f35464f359937e4f2ad362cd7919223b012dfd3f/media/BUILD.gn [modify] https://crrev.com/f35464f359937e4f2ad362cd7919223b012dfd3f/media/formats/webm/webm_constants.h [modify] https://crrev.com/f35464f359937e4f2ad362cd7919223b012dfd3f/media/formats/webm/webm_crypto_helpers.cc [modify] https://crrev.com/f35464f359937e4f2ad362cd7919223b012dfd3f/media/formats/webm/webm_crypto_helpers.h [add] https://crrev.com/f35464f359937e4f2ad362cd7919223b012dfd3f/media/formats/webm/webm_crypto_helpers_unittest.cc
,
Oct 4 2016
webm subsample encryption spec is now available at http://www.webmproject.org/docs/webm-encryption/#46-subsample-encrypted-block-format
,
Oct 4 2016
,
Oct 4 2016
,
Oct 10 2016
The following revision refers to this bug: https://chromium.googlesource.com/chromium/src.git/+/2cf59b5b692ff2496e03baba36349c5a4f920344 commit 2cf59b5b692ff2496e03baba36349c5a4f920344 Author: kqyang <kqyang@chromium.org> Date: Mon Oct 10 22:16:17 2016 Add browser test for vp9 subsample encrypted content (http://www.webmproject.org/docs/webm-encryption/#46-subsample-encrypted-block-format) Bug= 630344 Review-Url: https://codereview.chromium.org/2345463004 Cr-Commit-Position: refs/heads/master@{#424261} [modify] https://crrev.com/2cf59b5b692ff2496e03baba36349c5a4f920344/chrome/browser/media/encrypted_media_browsertest.cc [modify] https://crrev.com/2cf59b5b692ff2496e03baba36349c5a4f920344/content/browser/media/encrypted_media_browsertest.cc [modify] https://crrev.com/2cf59b5b692ff2496e03baba36349c5a4f920344/media/test/data/README [rename] https://crrev.com/2cf59b5b692ff2496e03baba36349c5a4f920344/media/test/data/bear-320x240-v-vp9_fullsample_enc-v.webm [add] https://crrev.com/2cf59b5b692ff2496e03baba36349c5a4f920344/media/test/data/bear-320x240-v-vp9_subsample_enc-v.webm |
||||||
►
Sign in to add a comment |
||||||
Comment 1 by kqyang@chromium.org
, Jul 21 2016