diff options
Diffstat (limited to 'vp8/decoder/dboolhuff.c')
| -rw-r--r-- | vp8/decoder/dboolhuff.c | 45 |
1 files changed, 31 insertions, 14 deletions
diff --git a/vp8/decoder/dboolhuff.c b/vp8/decoder/dboolhuff.c index 7e7b05aa6..aa7a56a02 100644 --- a/vp8/decoder/dboolhuff.c +++ b/vp8/decoder/dboolhuff.c @@ -10,18 +10,20 @@ #include "dboolhuff.h" -#include "vpx_ports/mem.h" -#include "vpx_mem/vpx_mem.h" 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) { br->user_buffer_end = source+source_sz; br->user_buffer = source; br->value = 0; br->count = -8; br->range = 255; + br->origin = origin; + br->key = key; if (source_sz && !source) return 1; @@ -32,19 +34,34 @@ int vp8dx_start_decode(BOOL_DECODER *br, return 0; } - void vp8dx_bool_decoder_fill(BOOL_DECODER *br) { - const unsigned char *bufptr; - const unsigned char *bufend; - VP8_BD_VALUE value; - int count; - bufend = br->user_buffer_end; - bufptr = br->user_buffer; - value = br->value; - count = br->count; - - VP8DX_BOOL_DECODER_FILL(count, value, bufptr, bufend); + const unsigned char *bufptr = br->user_buffer; + const unsigned char *bufend = br->user_buffer_end; + VP8_BD_VALUE value = br->value; + int count = br->count; + int shift = VP8_BD_VALUE_SIZE - 8 - (count + 8); + size_t bits_left = (bufend - bufptr)*CHAR_BIT; + int x = (int)(shift + CHAR_BIT - bits_left); + int loop_end = 0; + + if(x >= 0) + { + count += VP8_LOTS_OF_BITS; + loop_end = x; + } + + if (x < 0 || bits_left) + { + while(shift >= loop_end) + { + count += CHAR_BIT; + value |= ((VP8_BD_VALUE)decrypt_byte(bufptr, br->origin, + br->key)) << shift; + ++bufptr; + shift -= CHAR_BIT; + } + } br->user_buffer = bufptr; br->value = value; |