| 0,0 → 1,125 |
|---|
| /* |
| * Copyright (c) 2001-2002, David Janssens |
| * Copyright (c) 2003, Yannick Verschueren |
| * Copyright (c) 2003, Communications and remote sensing Laboratory, Universite catholique de Louvain, Belgium |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS `AS IS' |
| * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
| * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| * POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "bio.h" |
| #include <setjmp.h> |
| |
| static unsigned char *bio_start, *bio_end, *bio_bp; |
| static unsigned int bio_buf; |
| static int bio_ct; |
| |
| extern jmp_buf j2k_error; |
| |
| /// <summary> |
| /// Number of bytes written. |
| /// </summary> |
| int bio_numbytes() { |
| return bio_bp-bio_start; |
| } |
| |
| /// <summary> |
| /// Init decoder. |
| /// </summary> |
| /// <param name="bp">Input buffer</param> |
| /// <param name="len">Input buffer length</param> |
| void bio_init_dec(unsigned char *bp, int len) { |
| bio_start=bp; |
| bio_end=bp+len; |
| bio_bp=bp; |
| bio_buf=0; |
| bio_ct=0; |
| } |
| |
| int bio_byteout() |
| { |
| bio_buf = (bio_buf << 8) & 0xffff; |
| bio_ct = bio_buf == 0xff00 ? 7 : 8; |
| if (bio_bp >= bio_end) |
| return 1; |
| *bio_bp++ = bio_buf >> 8; |
| return 0; |
| } |
| |
| /// <summary> |
| /// Read byte. |
| /// </summary> |
| int bio_bytein() { |
| bio_buf=(bio_buf<<8)&0xffff; |
| bio_ct=bio_buf==0xff00?7:8; |
| if (bio_bp>=bio_end) return 1; //longjmp(j2k_error, 1); |
| bio_buf|=*bio_bp++; |
| return 0; |
| } |
| |
| /// <summary> |
| /// Read bit. |
| /// </summary> |
| int bio_getbit() { |
| if (bio_ct==0) { |
| bio_bytein(); |
| } |
| bio_ct--; |
| return (bio_buf>>bio_ct)&1; |
| } |
| |
| /// <summary> |
| /// Read bits. |
| /// </summary> |
| /// <param name="n">Number of bits to read</param> |
| int bio_read(int n) { |
| int i, v; |
| v=0; |
| for (i=n-1; i>=0; i--) { |
| v+=bio_getbit()<<i; |
| } |
| return v; |
| } |
| |
| /// <summary> |
| /// Flush bits. |
| /// </summary> |
| int bio_flush() { |
| bio_ct=0; |
| bio_byteout(); |
| if (bio_ct==7) { |
| bio_ct=0; |
| if ( bio_byteout()) return 1;; |
| } |
| return 0; |
| } |
| |
| /// <summary> |
| /// </summary> |
| int bio_inalign() { |
| bio_ct=0; |
| if ((bio_buf&0xff)==0xff) { |
| if( bio_bytein()) return 1; |
| bio_ct=0; |
| } |
| return 0; |
| } |