Amazon Instant encv/enca

[blimey]

I've noticed that Amazon Instant flash streaming for paid programs (as opposed to free or prime program streaming) is encoded differently than the free/prime streaming.

Free/prime are encoded using the common avc1/mp4a for the video codec id/audio codec id.

While paid programs are encoded using encv/enca for the video codec id/audio codec id.

I don't know what is encv/enca, as found in a flash container. Except that the resulting file won't play and seems encrypted. The MP4 does mention encryption, but is this beyond the usual flash tricks, how does the flash player handle it? Does anyone else know?

[KSV]

encv = Encrypted Video
enca = Encrypted Audio

it's part of Adobe Flash Access DRM. Flash player have separate module for handling drm which is downloaded while you try to play the protected content for first time. it's similar to indivbox dll method used by Microsoft. as like most drm systems encryption algorithms used are publicly available but the main hurdle is to retrieve the decryption key.

AFAIK currently no public tool or method is available to decrypt those videos.

[blimey]

Thanks. A search about Flash Access has revealed more details. I'm surprised I hadn't run into it before. I suppose its use will become more common.

I'm wondering if tools that support recording from the flash player, as opposed to direct downloading, will be of any use. I tried such feature in Tubedigger, but it produced the same file as the direct download method.

[retief]

Is this something new that you noticed? A few months ago, I could archive any purchases I made on Amazon VOD via GetFLV.

[blimey]

Yes, it is new. I've even seen some content go from unencrypted to encrypted (avc1/mp4a to encv/enca) in just the past few weeks.

Whether getflv can handle encv/enca, I would guess not. Because I suspect that is just how the file exists on the server. I don't think the encv/enca encryption is done on-the-fly, because the file contents are consistent from session to session even many days apart.

There is still quite a bit of their content in the clear though.

[heyadam]

Because this issue has come up again and again. Let's read the docs and do something!

I wanted to cross-reference a few threads:

Amazon Prime
http://stream-recorder.com/forum/dow...eo-t11367.html

City TV (with FlashAccess documentation)
http://stream-recorder.com/forum/pro...ht=flashaccess

http://stream-recorder.com/forum/cit...ht=flashaccess

http://stream-recorder.com/forum/rem...ht=flashaccess

This type of protection is becoming more prevalent.

Some recommendations to overcome this protection:
--Flash player has to decode the video to play it.
--Flash scripting is rudimentary so the decrypt function may be ActionScript.
--I can't imagine that the decrypt module is terribly well-programmed or strong. It is Adobe Flash after all!

Anyway, let's crowd-solve this problem!

Regards,
heyadam