GoToMeeting Codec: Difference between revisions
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bytes 5.. remainder of payload, format unknown | bytes 5.. remainder of payload, format unknown | ||
Supported chunk types are 0xC8-0xCD. | |||
It appears that the minimum size for a G2M2 frame (possibly a no-change frame) is 14 bytes. This includes the 4 signature bytes, a 4-byte length indicating a chunk length of 6, and a 6-byte payload of type 0xCA followed by 5 more bytes. | It appears that the minimum size for a G2M2 frame (possibly a no-change frame) is 14 bytes. This includes the 4 signature bytes, a 4-byte length indicating a chunk length of 6, and a 6-byte payload of type 0xCA followed by 5 more bytes. | ||
G2M3 bears much similarity to G2M2 at the surface level. Naturally, each frame has a signature of 'G2M3'. | G2M3 bears much similarity to G2M2 at the surface level. Naturally, each frame has a signature of 'G2M3'. | ||
=== Chunk C8 === | |||
This seems to contain display information. | |||
Chunk contents: | |||
20 bytes ??? | |||
1 byte colour depth (4, 8, 16, 24 or 32) | |||
for 4/8bpp there is a palette in standard RGBTUPLE format | |||
for 16-32bpp there are four bitmasks for each field | |||
[[Category:Video Codecs]] | [[Category:Video Codecs]] | ||
Revision as of 12:44, 8 November 2011
- FourCC: G2M2, G2M3, G2M4
- Company: GoToMeeting (Citrix)
- Samples:
This is a codec used to save recordings in GoToMeeting. The codec also calls itself GoToWebinar (see http://www.gotowebinar.com/).
Win32 binary decoder available here: http://www.gotomeeting.com/codec
According to samples, all G2M2 video frames begin with the characters 'G2M2', followed by a series of chunks. Each chunk has the following layout:
bytes 0-3 length of chunk payload, not including this length field byte 4 type of chunk bytes 5.. remainder of payload, format unknown
Supported chunk types are 0xC8-0xCD.
It appears that the minimum size for a G2M2 frame (possibly a no-change frame) is 14 bytes. This includes the 4 signature bytes, a 4-byte length indicating a chunk length of 6, and a 6-byte payload of type 0xCA followed by 5 more bytes.
G2M3 bears much similarity to G2M2 at the surface level. Naturally, each frame has a signature of 'G2M3'.
Chunk C8
This seems to contain display information.
Chunk contents:
20 bytes ??? 1 byte colour depth (4, 8, 16, 24 or 32) for 4/8bpp there is a palette in standard RGBTUPLE format for 16-32bpp there are four bitmasks for each field