static void dv_decode_ac(GetBitContext *gb, BlockInfo *mb, DCTELEM *block) { int last_index = get_bits_size(gb); const uint8_t *scan_table = mb->scan_table; const uint8_t *shift_table = mb->shift_table; int pos = mb->pos; int partial_bit_count = mb->partial_bit_count; int level, pos1, run, vlc_len, index; OPEN_READER(re, gb); UPDATE_CACHE(re, gb); /* if we must parse a partial vlc, we do it here */ if (partial_bit_count > 0) { re_cache = ((unsigned)re_cache >> partial_bit_count) | (mb->partial_bit_buffer << (sizeof(re_cache)*8 - partial_bit_count)); re_index -= partial_bit_count; mb->partial_bit_count = 0; } /* get the AC coefficients until last_index is reached */ for(;;) { #ifdef VLC_DEBUG printf("%2d: bits=%04x index=%d\n", pos, SHOW_UBITS(re, gb, 16), re_index); #endif /* our own optimized GET_RL_VLC */ index = NEG_USR32(re_cache, TEX_VLC_BITS); vlc_len = dv_rl_vlc[index].len; if (vlc_len < 0) { index = NEG_USR32((unsigned)re_cache << TEX_VLC_BITS, -vlc_len) + dv_rl_vlc[index].level; vlc_len = TEX_VLC_BITS - vlc_len; } level = dv_rl_vlc[index].level; run = dv_rl_vlc[index].run; /* gotta check if we're still within gb boundaries */ if (re_index + vlc_len > last_index) { /* should be < 16 bits otherwise a codeword could have been parsed */ mb->partial_bit_count = last_index - re_index; mb->partial_bit_buffer = NEG_USR32(re_cache, mb->partial_bit_count); re_index = last_index; break; } re_index += vlc_len; #ifdef VLC_DEBUG printf("run=%d level=%d\n", run, level); #endif pos += run; if (pos >= 64) break; if (level) { pos1 = scan_table[pos]; block[pos1] = level << shift_table[pos1]; } UPDATE_CACHE(re, gb); } CLOSE_READER(re, gb); mb->pos = pos; }
static void dv_decode_ac(GetBitContext *gb, BlockInfo *mb, DCTELEM *block) { int last_index = get_bits_size(gb); const uint8_t *scan_table = mb->scan_table; const uint8_t *shift_table = mb->shift_table; int pos = mb->pos; int partial_bit_count = mb->partial_bit_count; int level, pos1, run, vlc_len, index; OPEN_READER(re, gb); UPDATE_CACHE(re, gb);   if (partial_bit_count > 0) { re_cache = ((unsigned)re_cache >> partial_bit_count) | (mb->partial_bit_buffer << (sizeof(re_cache)*8 - partial_bit_count)); re_index -= partial_bit_count; mb->partial_bit_count = 0; }   for(;;) { #ifdef VLC_DEBUG printf("%2d: bits=%04x index=%d\n", pos, SHOW_UBITS(re, gb, 16), re_index); #endif   index = NEG_USR32(re_cache, TEX_VLC_BITS); vlc_len = dv_rl_vlc[index].len; if (vlc_len < 0) { index = NEG_USR32((unsigned)re_cache << TEX_VLC_BITS, -vlc_len) + dv_rl_vlc[index].level; vlc_len = TEX_VLC_BITS - vlc_len; } level = dv_rl_vlc[index].level; run = dv_rl_vlc[index].run;   if (re_index + vlc_len > last_index) {   mb->partial_bit_count = last_index - re_index; mb->partial_bit_buffer = NEG_USR32(re_cache, mb->partial_bit_count); re_index = last_index; break; } re_index += vlc_len; #ifdef VLC_DEBUG printf("run=%d level=%d\n", run, level); #endif pos += run; if (pos >= 64) break; if (level) { pos1 = scan_table[pos]; block[pos1] = level << shift_table[pos1]; } UPDATE_CACHE(re, gb); } CLOSE_READER(re, gb); mb->pos = pos; }