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Hi, thanks for this awesome documentation on Airplay. I've gotten airplay screen mirroring (actual mirroring, not just the simple video playback) working from an Android device. This requires a custom build of Android.

Anyways, the problem I'm running into is that it the mirroring doesn't seem to frame/crop the live feed properly. The resultant picture is partially off screen and too large. From my experimentation, it seems that the airplay headers contain what seem to be framing info. Tweaking these bytes in the codec data header seem to adjust the scale and translation of the image on the Apple TV:

Sample first 64 bytes of a header:

1f 00 00 00 01 00 06 00 1d 9a 9f 59 ef de 00 00
00 00 58 44 00 00 22 44 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 58 44 00 00 22 44
00 00 50 43 00 00 10 42 00 c0 57 44 00 c0 21 44

It seems that the last 48 bytes (last 3 rows) are what affect the feed placement on the TV. I've been working on trying to make heads or tails of it, but haven't put together on what these values mean. For example, changing some of the 44s to a 43 result in the feed going black. My current suspicion is that it may be a transformation matrix, but that does not seem entirely correct either.

Any ideas or thoughts on this?

I did not found it in your extensive documentation and could not find it online or able to find it with the help of Wireshark.

I mean this phrase:

Events are delivered using a POST request for sending an XML property list to the /event location.

I would like to enable the reverse events in node-airplay and you discuss the ability and therefore I would like to know if you could provide more information about this ability in the documentation.

I've looked at the specification but the described connection initiated back I can't see with Wireshark and thats why I was wondering which port or if you have any other tips/information you could share in the documentation.

Thnx.

Line 508:

<pre><code>POST /reverse

Should be:

Line 508:

<pre><code>POST /reverse HTTP/1.1

In section 5.4 Metadata, no example of valid DMAP tagged data is given - just "<DMAP DATA>". A valid example for DMAP DATA is:

0x00000000  6d 6c 69 74 00 00 00 2b 6d 69 6e 6d 00 00 00 08  mlit...+minm....
0x00000010  49 54 45 4d 4e 41 4d 45 61 73 61 72 00 00 00 06  ITEMNAMEasar....
0x00000020  41 52 54 49 53 54 61 73 61 6c 00 00 00 05 41 4c  ARTISTasal....AL
0x00000030  42 55 4d                                         BUM

i.e.:
"mlit", big endian unsigned 4 byte int total message length - 8,
"minm", big endian unsigned 4 byte int string length, item name string,
"asar", big endian unsigned 4 byte int string length, artist name string,
"asal", big endian unsigned 4 byte int string length, album name string

Can you update this main repository?

There are several changes here:

• https://github.com/nto/nto.github.com/network

Thanks in advance.