diff options
Diffstat (limited to 'libopenjpeg/bio.c')
| -rw-r--r-- | libopenjpeg/bio.c | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/libopenjpeg/bio.c b/libopenjpeg/bio.c new file mode 100644 index 00000000..400523d7 --- /dev/null +++ b/libopenjpeg/bio.c @@ -0,0 +1,182 @@ +/* + * 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 <stdio.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 encoder. */ +/* </summary> */ +/* <param name="bp">Output buffer</param> */ +/* <param name="len">Output buffer length</param> */ +void bio_init_enc(unsigned char *bp, int len) +{ + bio_start = bp; + bio_end = bp + len; + bio_bp = bp; + bio_buf = 0; + bio_ct = 8; +} + +/* <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; +} + +/* <summary> */ +/* Write byte. --> function modified to eliminate longjmp !!! */ +/* </summary> */ +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. --> function modified to eliminate longjmp !! */ +/* </summary> */ +int bio_bytein() +{ + bio_buf = (bio_buf << 8) & 0xffff; + bio_ct = bio_buf == 0xff00 ? 7 : 8; + if (bio_bp >= bio_end) + return 1; + bio_buf |= *bio_bp++; + return 0; +} + +/* <summary> */ +/* Write bit. */ +/* </summary> */ +/* <param name="b">Bit to write (0 or 1)</param> */ +void bio_putbit(int b) +{ + if (bio_ct == 0) { + bio_byteout(); + } + bio_ct--; + bio_buf |= b << bio_ct; +} + +/* <summary> */ +/* Read bit. */ +/* </summary> */ +int bio_getbit() +{ + if (bio_ct == 0) { + bio_bytein(); + } + bio_ct--; + return (bio_buf >> bio_ct) & 1; +} + +/* <summary> */ +/* Write bits. */ +/* </summary> */ +/* <param name="v">Value of bits</param> */ +/* <param name="n">Number of bits to write</param> */ +void bio_write(int v, int n) +{ + int i; + for (i = n - 1; i >= 0; i--) { + bio_putbit((v >> i) & 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. MOdified to eliminate longjmp !! */ +/* </summary> */ +int bio_flush() +{ + bio_ct = 0; + if (bio_byteout()) + return 1; + 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; +} |