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1Library: libcook
2Imported by : Mohamed Tarek
3
4These files comprise a rm parser and a cook decoder based on the decoder
5from ffmpeg.
6
7LICENSING INFORMATION
8
9ffmpeg is licensed under the Lesser GNU General Public License and the
10file cook.c is Copyright 2003 Sascha Sommer and 2005 Benjamin Larsson.
11
12IMPORT DETAILS
13
14The decoder is based on ffmpeg-svn r18079.
15
16CONVERSION TO FIXED-POINT
17
18A patch from ffmpeg's mailing list was used to convert the decoder to
19use fixed-point arithmetic. The patch was done by Ian Braithwaite, and
20discussed here :
21
22http://thread.gmane.org/gmane.comp.video.ffmpeg.devel/46024
23
24The patch is a bit dated (2007) so the modifications to cook.c had to
25be done manually. The patch was also applied to cookdata.h and was
26used to create cookdata_fixpoint.h, cook_fixpoint.h and
27cook_fixp_mdct.h.
28
29cook_fixp_mdct.h and parts from cookdata_fixpoint.h were dropped and
30rockbox's mdct library is now used in both the test program and the
31real codec.
32
33Note : Only parts of the patch were committed to ffmpeg's repository.
34
35TESTING
36
37The test program should compile in any Unix-like environment using the
38command "make -f Makefile.test".
39
40For ARM targets add -DCPU_ARM to CFLAGS in Makefile.test to make use of
41the asm ARM optimisations in rockbox's mdct library.
42
43For Big-endian targets, change -D"ROCKBOX_LITTLE_ENDIAN=1"
44to -D"ROCKBOX_BIG_ENDIAN=1" in Makefile.test.
45
46Running "./cooktest file.rm" will decode the audio data to a WAV file
47called "output.wav" in the current directory.