diff options
Diffstat (limited to 'vp8/decoder/dboolhuff.h')
| -rw-r--r-- | vp8/decoder/dboolhuff.h | 62 |
1 files changed, 26 insertions, 36 deletions
diff --git a/vp8/decoder/dboolhuff.h b/vp8/decoder/dboolhuff.h index 1a08c057b..46a4dd60e 100644 --- a/vp8/decoder/dboolhuff.h +++ b/vp8/decoder/dboolhuff.h @@ -9,21 +9,36 @@ */ -#ifndef DBOOLHUFF_H -#define DBOOLHUFF_H +#ifndef DBOOLHUFF_H_ +#define DBOOLHUFF_H_ + #include <stddef.h> #include <limits.h> + #include "vpx_config.h" #include "vpx_ports/mem.h" #include "vpx/vpx_integer.h" typedef size_t VP8_BD_VALUE; -# define VP8_BD_VALUE_SIZE ((int)sizeof(VP8_BD_VALUE)*CHAR_BIT) +#define VP8_BD_VALUE_SIZE ((int)sizeof(VP8_BD_VALUE)*CHAR_BIT) + /*This is meant to be a large, positive constant that can still be efficiently loaded as an immediate (on platforms like ARM, for example). Even relatively modest values like 100 would work fine.*/ -# define VP8_LOTS_OF_BITS (0x40000000) +#define VP8_LOTS_OF_BITS (0x40000000) + +static unsigned char decrypt_byte(const unsigned char *ch, + const unsigned char *origin, + const unsigned char *key) +{ +#if CONFIG_DECRYPT + const int offset = (int)(ch - origin); + return *ch ^ key[offset % 32]; // VP8_DECRYPT_KEY_SIZE +#else + return *ch; +#endif +} typedef struct { @@ -32,46 +47,20 @@ typedef struct VP8_BD_VALUE value; int count; unsigned int range; + const unsigned char *origin; + const unsigned char *key; } BOOL_DECODER; DECLARE_ALIGNED(16, extern const unsigned char, vp8_norm[256]); int vp8dx_start_decode(BOOL_DECODER *br, const unsigned char *source, - unsigned int source_sz); + unsigned int source_sz, + const unsigned char *origin, + const unsigned char *key); void vp8dx_bool_decoder_fill(BOOL_DECODER *br); -/*The refill loop is used in several places, so define it in a macro to make - sure they're all consistent. - An inline function would be cleaner, but has a significant penalty, because - multiple BOOL_DECODER fields must be modified, and the compiler is not smart - enough to eliminate the stores to those fields and the subsequent reloads - from them when inlining the function.*/ -#define VP8DX_BOOL_DECODER_FILL(_count,_value,_bufptr,_bufend) \ - do \ - { \ - int shift = VP8_BD_VALUE_SIZE - 8 - ((_count) + 8); \ - int loop_end, x; \ - size_t bits_left = ((_bufend)-(_bufptr))*CHAR_BIT; \ - \ - x = (int)(shift + CHAR_BIT - bits_left); \ - loop_end = 0; \ - if(x >= 0) \ - { \ - (_count) += VP8_LOTS_OF_BITS; \ - loop_end = x; \ - if(!bits_left) break; \ - } \ - while(shift >= loop_end) \ - { \ - (_count) += CHAR_BIT; \ - (_value) |= (VP8_BD_VALUE)*(_bufptr)++ << shift; \ - shift -= CHAR_BIT; \ - } \ - } \ - while(0) \ - static int vp8dx_decode_bool(BOOL_DECODER *br, int probability) { unsigned int bit = 0; @@ -151,4 +140,5 @@ static int vp8dx_bool_error(BOOL_DECODER *br) /* No error. */ return 0; } -#endif + +#endif // DBOOLHUFF_H_ |