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| author | Andreas Rheinhardt <andreas.rheinhardt@gmail.com> | 2020-10-12 05:24:42 +0200 |
|---|---|---|
| committer | Andreas Rheinhardt <andreas.rheinhardt@gmail.com> | 2020-10-12 22:20:37 +0200 |
| commit | 9eb7d8b45d0497d75e5655b79d9eea63bedc833c (patch) | |
| tree | 69f95eb73cc15a457a840c3f915c85edd3ba25ad /libavcodec/vlc.h | |
| parent | e78bbbc2b1e413d11e9edf818e1dc07f16aecf91 (diff) | |
| download | ffmpeg-9eb7d8b45d0497d75e5655b79d9eea63bedc833c.tar.gz | |
avcodec/vlc, bitstream: Allow to use BE codes to initialize LE VLC
This is easily possible because ff_init_vlc_sparse() already transforms
both LE as well as BE codes to a normal form internally before
processing them further. This will be used in subsequent commits.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Diffstat (limited to 'libavcodec/vlc.h')
| -rw-r--r-- | libavcodec/vlc.h | 29 |
1 files changed, 19 insertions, 10 deletions
diff --git a/libavcodec/vlc.h b/libavcodec/vlc.h index 42ccddf3fc..22d3e33485 100644 --- a/libavcodec/vlc.h +++ b/libavcodec/vlc.h @@ -51,26 +51,35 @@ int ff_init_vlc_sparse(VLC *vlc, int nb_bits, int nb_codes, int flags); void ff_free_vlc(VLC *vlc); -#define INIT_VLC_LE 2 +/* If INIT_VLC_INPUT_LE is set, the LSB bit of the codes used to + * initialize the VLC table is the first bit to be read. */ +#define INIT_VLC_INPUT_LE 2 +/* If set the VLC is intended for a little endian bitstream reader. */ +#define INIT_VLC_OUTPUT_LE 8 +#define INIT_VLC_LE (INIT_VLC_INPUT_LE | INIT_VLC_OUTPUT_LE) #define INIT_VLC_USE_NEW_STATIC 4 -#define INIT_VLC_SPARSE_STATIC(vlc, bits, a, b, c, d, e, f, g, h, i, j, static_size) \ +#define INIT_CUSTOM_VLC_SPARSE_STATIC(vlc, bits, a, b, c, d, e, f, g, \ + h, i, j, flags, static_size) \ do { \ static VLC_TYPE table[static_size][2]; \ (vlc)->table = table; \ (vlc)->table_allocated = static_size; \ ff_init_vlc_sparse(vlc, bits, a, b, c, d, e, f, g, h, i, j, \ - INIT_VLC_USE_NEW_STATIC); \ + flags | INIT_VLC_USE_NEW_STATIC); \ } while (0) +#define INIT_VLC_SPARSE_STATIC(vlc, bits, a, b, c, d, e, f, g, h, i, j, static_size) \ + INIT_CUSTOM_VLC_SPARSE_STATIC(vlc, bits, a, b, c, d, e, f, g, \ + h, i, j, 0, static_size) + #define INIT_LE_VLC_SPARSE_STATIC(vlc, bits, a, b, c, d, e, f, g, h, i, j, static_size) \ - do { \ - static VLC_TYPE table[static_size][2]; \ - (vlc)->table = table; \ - (vlc)->table_allocated = static_size; \ - ff_init_vlc_sparse(vlc, bits, a, b, c, d, e, f, g, h, i, j, \ - INIT_VLC_USE_NEW_STATIC | INIT_VLC_LE); \ - } while (0) + INIT_CUSTOM_VLC_SPARSE_STATIC(vlc, bits, a, b, c, d, e, f, g, \ + h, i, j, INIT_VLC_LE, static_size) + +#define INIT_CUSTOM_VLC_STATIC(vlc, bits, a, b, c, d, e, f, g, flags, static_size) \ + INIT_CUSTOM_VLC_SPARSE_STATIC(vlc, bits, a, b, c, d, e, f, g, \ + NULL, 0, 0, flags, static_size) #define INIT_VLC_STATIC(vlc, bits, a, b, c, d, e, f, g, static_size) \ INIT_VLC_SPARSE_STATIC(vlc, bits, a, b, c, d, e, f, g, NULL, 0, 0, static_size) |