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/*
* Copyright (c) 2014, Mathieu Malaterre <mathieu.malaterre@voxxl.com>
* 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.
*/
/*
* Extract all JP2 files contained within a PDF file.
*
* Technically you could simply use mutool, eg:
*
* $ mutool show -be -o obj58.jp2 Bug691816.pdf 58
*
* to extract a given JP2 file from within a PDF
* However it happens sometimes that the PDF is itself corrupted, this tools is
* a lame PDF parser which only extract stream contained in JPXDecode box
* only work on linux since I need memmem function
*/
/*
* Add support for other signatures:
*
* obj<</Subtype/Image/Length 110494/Filter/JPXDecode/BitsPerComponent 8/ColorSpace/DeviceRGB/Width 712/Height 1052>>stream
*/
#define _GNU_SOURCE
#include <string.h>
#include <stdio.h>
#include <stddef.h>
#include <assert.h>
int main(int argc, char *argv[])
{
#define NUMJP2 32
int i, c = 0;
long offets[NUMJP2];
char buffer[512];
#define BUFLEN 4096
int cont = 1;
FILE *f;
size_t nread;
char haystack[BUFLEN];
const char needle[] = "JPXDecode";
const size_t nlen = strlen( needle );
const size_t flen = BUFLEN - nlen;
char *fpos = haystack + nlen;
const char *filename;
if( argc < 2 ) return 1;
filename = argv[1];
memset( haystack, 0, nlen );
f = fopen( filename, "rb" );
while( cont ) {
const char *ret;
size_t hlen;
nread = fread(fpos, 1, flen, f);
hlen = nlen + nread;
ret = memmem( haystack, hlen, needle, nlen);
if( ret ) {
const long cpos = ftell(f);
const ptrdiff_t diff = ret - haystack;
assert( diff >= 0 );
/*fprintf( stdout, "Found it: %lx\n", (ptrdiff_t)cpos - (ptrdiff_t)hlen + diff);*/
offets[c++] = (ptrdiff_t)cpos - (ptrdiff_t)hlen + diff;
}
cont = (nread == flen);
memcpy( haystack, haystack + nread, nlen );
}
assert( feof( f ) );
for( i = 0; i < c; ++i ) {
int s, len = 0;
char *r;
const int ret = fseek(f, offets[i], SEEK_SET);
assert( ret == 0 );
r = fgets(buffer, sizeof(buffer), f);
assert( r );
/*fprintf( stderr, "DEBUG: %s", r );*/
s = sscanf(r, "JPXDecode]/Length %d/Width %*d/BitsPerComponent %*d/Height %*d", &len);
if( s == 0 ) {
// try again harder
const int ret = fseek(f, offets[i] - 40, SEEK_SET); // 40 is magic number
assert( ret == 0 );
r = fgets(buffer, sizeof(buffer), f);
assert( r );
const char needle2[] = "/Length";
char * s2 = strstr(buffer, needle2);
s = sscanf(s2, "/Length %d/", &len);
}
if( s == 1 ) {
FILE *jp2;
int j;
char jp2fn[512];
sprintf( jp2fn, "%s.%d.jp2", filename, i );
jp2 = fopen( jp2fn, "wb" );
for( j = 0; j < len; ++j ) {
int v = fgetc(f);
int ret2 = fputc(v, jp2);
assert( ret2 != EOF );
}
fclose( jp2 );
#if 0
/* TODO need to check we reached endstream */
r = fgets(buffer, sizeof(buffer), f);
fprintf( stderr, "DEBUG: [%s]", r );
r = fgets(buffer, sizeof(buffer), f);
fprintf( stderr, "DEBUG: [%s]", r );
#endif
}
}
fclose(f);
return 0;
}
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