[FFmpeg-devel] [RFC][PATCH] CRC64

James Almer jamrial at gmail.com
Sun Jan 27 07:52:12 CET 2013

In the middle of adding support for TTA encrypted streams i
realized that i was writting code to process the passwords using
a CRC implementation inside the muxer, when ffmpeg already has 
built in code to do the same.
Unfortunately said code only supports up to CRC32 and TTA uses 
CRC64, so here's an attempt to add support for CRCs of up 
to 64 bits to libavutil.

I added new functions for this, since i'm sure changing public 
functions is not accepted.
These new functions are essentially the same as the old ones,
but with support for CRCs of up to 64 bits, and can be used in
place of the old ones with the same results.

I'm sending this as RFC mainly because i want to be 100% sure
there's no (or no severe) API/ABI break.


TODO: If accepted, lavu/lavf minor bumps, APIchanges entries and 
maybe doxy.

James Almer (3):
  lavu: Add av_crc2() and av_crc_init2()
  lavu: Add CRC64-ECMA standard tables
  tta: Add support for encrypted streams

 libavcodec/tta.c     |  27 +++++---
 libavformat/tta.c    |  50 ++++++++++++++-
 libavutil/crc.c      |  42 +++++++++---
 libavutil/crc.h      |   9 ++-
 libavutil/crc_data.h | 176 +++++++++++++++++++++++++++++++++++++++++++++++++++
 tests/ref/fate/crc   |   2 +
 6 files changed, 285 insertions(+), 21 deletions(-)


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