1230026 - [EME] Support 'webm' initDataType format for ClearKey initData in MP4

Status: RESOLVED FIXED

(Core :: Audio/Video: Playback, defect)

Description

[Chris Pearce [:cpearce (Not reading bugmail)]]

Google's shaka-player uses 'webm' initData format for its MP4 content. It's trivial to add support for this initData format.

And note that the initData format is independent of the underlying stream type. So it's valid to provide 'webm' initData for an MP4 stream, though you won't be getting the initData out of the MP4 file's PSSH of course, you'll be getting it out-of-band somehow.

Comment 1

[Chris Pearce [:cpearce (Not reading bugmail)]]

Attachment: MozReview Request: Bug 1230026 - Support 'webm' initDataType format for MP4 ClearKey initData. r=gerald

Bug 1230026 - Support 'webm' initDataType format for MP4 ClearKey initData. r?gerald

Comment 2

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

Comment on attachment 8695101 [details]
MozReview Request: Bug 1230026 - Support 'webm' initDataType format for MP4 ClearKey initData. r=gerald

https://reviewboard.mozilla.org/r/27011/#review24405

Looks correct. Just wondering about the magic value:

::: media/gmp-clearkey/0.1/ClearKeySession.cpp:72
(Diff revision 1)
> +  } else if (aInitDataType == "webm" && aInitDataSize == 16) {

Why 16?

Comment 3

[Chris Pearce [:cpearce (Not reading bugmail)]]

Comment on attachment 8695101 [details]
MozReview Request: Bug 1230026 - Support 'webm' initDataType format for MP4 ClearKey initData. r=gerald

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/27011/diff/1-2/

Comment 4

[Chris Pearce [:cpearce (Not reading bugmail)]]

Attachment: MozReview Request: Bug 1230026 - Add test for 'webm' initDataType for ClearKey initData. r?gerald

Bug 1230026 - Add test for 'webm' initDataType for ClearKey initData. r?gerald

Comment 5

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

(In reply to Chris Pearce (:cpearce) from comment #3)
> Comment on attachment 8695101 [details]
> MozReview Request: Bug 1230026 - Support 'webm' initDataType format for MP4
> ClearKey initData. r=gerald
> 
> Review request updated; see interdiff:
> https://reviewboard.mozilla.org/r/27011/diff/1-2/

The interdiff looks empty... Is that just because you've added the test?

Comment 6

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

Comment on attachment 8695118 [details]
MozReview Request: Bug 1230026 - Add test for 'webm' initDataType for ClearKey initData. r?gerald

https://reviewboard.mozilla.org/r/27017/#review24407

Comment 7

[Pulsebot]

https://hg.mozilla.org/integration/mozilla-inbound/rev/fd69513f86b7
https://hg.mozilla.org/integration/mozilla-inbound/rev/a8b4b4cdab7b

Comment 8

[Chris Pearce [:cpearce (Not reading bugmail)]]

(In reply to Gerald Squelart [:gerald] from comment #2)
> Comment on attachment 8695101 [details]
> MozReview Request: Bug 1230026 - Support 'webm' initDataType format for MP4
> ClearKey initData. r=gerald
> 
> https://reviewboard.mozilla.org/r/27011/#review24405
> 
> Looks correct. Just wondering about the magic value:
> 
> ::: media/gmp-clearkey/0.1/ClearKeySession.cpp:72
> (Diff revision 1)
> > +  } else if (aInitDataType == "webm" && aInitDataSize == 16) {
> 
> Why 16?

That's the size of a CENC-CTR128 keyId. 128 bits = 16 bytes.

(In reply to Gerald Squelart [:gerald] from comment #5)
> (In reply to Chris Pearce (:cpearce) from comment #3)
> > Comment on attachment 8695101 [details]
> > MozReview Request: Bug 1230026 - Support 'webm' initDataType format for MP4
> > ClearKey initData. r=gerald
> > 
> > Review request updated; see interdiff:
> > https://reviewboard.mozilla.org/r/27011/diff/1-2/
> 

Yeah... Still learning how to drive this reviewboard thing...
> The interdiff looks empty... Is that just because you've added the test?

Comment 9

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/fd69513f86b7
https://hg.mozilla.org/mozilla-central/rev/a8b4b4cdab7b