📄 jpg.c
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#include <stdio.h>
#include <memory.h>
#include <stdlib.h>
#include <malloc.h>
#include <setjmp.h>
#include "jpeglib.h"
#include "jpg.h"
struct my_error_mgr {
struct jpeg_error_mgr pub; /* "public" fields */
jmp_buf setjmp_buffer; /* for return to caller */
};
typedef struct my_error_mgr * my_error_ptr;
METHODDEF(void)
my_error_exit (j_common_ptr cinfo)
{
/* cinfo->err really points to a my_error_mgr struct, so coerce pointer */
my_error_ptr myerr = (my_error_ptr) cinfo->err;
/* Always display the message. */
/* We could postpone this until after returning, if we chose. */
(*cinfo->err->output_message)(cinfo);
/* Return control to the setjmp point */
longjmp(myerr->setjmp_buffer, 1);
}
int unpack_jpg(jpg_info_t* jinfo)
{
struct jpeg_decompress_struct cinfo;
/* We use our private extension JPEG error handler.
* Note that this struct must live as long as the main JPEG parameter
* struct, to avoid dangling-pointer problems.
*/
struct my_error_mgr jerr;
/* More stuff */
JSAMPARRAY buffer; /* Output row buffer */
int row_stride; /* physical row width in output buffer */
cinfo.err = jpeg_std_error(&jerr.pub);
jerr.pub.error_exit = my_error_exit;
jpeg_create_decompress(&cinfo);
jpeg_memory_src(&cinfo, jinfo->jpg_buffer, jinfo->jpg_buffer_length);
jpeg_read_header(&cinfo, TRUE);
jpeg_start_decompress(&cinfo);
/* JSAMPLEs per row in output buffer */
row_stride = cinfo.output_width * cinfo.output_components;
/* Make a one-row-high sample array that will go away when done with image */
buffer = (*cinfo.mem->alloc_sarray)
((j_common_ptr) &cinfo, JPOOL_IMAGE, row_stride, 1);
jinfo->width=cinfo.output_width;
jinfo->height=cinfo.output_height;
jinfo->jpg_surface=(unsigned char*)malloc(jinfo->width*jinfo->height*3);
while (cinfo.output_scanline < cinfo.output_height) {
unsigned char* temp_src_buffer;
unsigned char* temp_des_buffer;
jpeg_read_scanlines(&cinfo, buffer, 1);
temp_src_buffer=(unsigned char*)(*buffer);
temp_des_buffer=jinfo->jpg_surface+jinfo->width*(cinfo.output_scanline-1)*3;
memcpy(temp_des_buffer,temp_src_buffer,row_stride);
}
jpeg_finish_decompress(&cinfo);
jpeg_destroy_decompress(&cinfo);
return 0;
}
int destroy_jpg(jpg_info_t* jinfo)
{
if (jinfo->jpg_surface!=NULL) {
free(jinfo->jpg_surface);
}
return 0;
}
#ifndef EXIT_FAILURE /* define exit() codes if not provided */
#define EXIT_FAILURE 1
#endif
/*
* Create the message string table.
* We do this from the master message list in jerror.h by re-reading
* jerror.h with a suitable definition for macro JMESSAGE.
* The message table is made an external symbol just in case any applications
* want to refer to it directly.
*/
#define JMESSAGE(code,string) string ,
const char * const jpeg_std_message_table[] = {
#include "jpg.h"
NULL
};
/*
* Error exit handler: must not return to caller.
*
* Applications may override this if they want to get control back after
* an error. Typically one would longjmp somewhere instead of exiting.
* The setjmp buffer can be made a private field within an expanded error
* handler object. Note that the info needed to generate an error message
* is stored in the error object, so you can generate the message now or
* later, at your convenience.
* You should make sure that the JPEG object is cleaned up (with jpeg_abort
* or jpeg_destroy) at some point.
*/
METHODDEF(void)
error_exit (j_common_ptr cinfo)
{
/* Always display the message */
(*cinfo->err->output_message) (cinfo);
/* Let the memory manager delete any temp files before we die */
jpeg_destroy(cinfo);
}
/*
* Actual output of an error or trace message.
* Applications may override this method to send JPEG messages somewhere
* other than stderr.
*/
METHODDEF(void)
output_message (j_common_ptr cinfo)
{
char buffer[JMSG_LENGTH_MAX];
/* Create the message */
(*cinfo->err->format_message) (cinfo, buffer);
/* Send it to stderr, adding a newline */
fprintf(stderr, "%s\n", buffer);
}
/*
* Decide whether to emit a trace or warning message.
* msg_level is one of:
* -1: recoverable corrupt-data warning, may want to abort.
* 0: important advisory messages (always display to user).
* 1: first level of tracing detail.
* 2,3,...: successively more detailed tracing messages.
* An application might override this method if it wanted to abort on warnings
* or change the policy about which messages to display.
*/
METHODDEF(void)
emit_message (j_common_ptr cinfo, int msg_level)
{
struct jpeg_error_mgr * err = cinfo->err;
if (msg_level < 0) {
/* It's a warning message. Since corrupt files may generate many warnings,
* the policy implemented here is to show only the first warning,
* unless trace_level >= 3.
*/
if (err->num_warnings == 0 || err->trace_level >= 3)
(*err->output_message) (cinfo);
/* Always count warnings in num_warnings. */
err->num_warnings++;
} else {
/* It's a trace message. Show it if trace_level >= msg_level. */
if (err->trace_level >= msg_level)
(*err->output_message) (cinfo);
}
}
/*
* Format a message string for the most recent JPEG error or message.
* The message is stored into buffer, which should be at least JMSG_LENGTH_MAX
* characters. Note that no '\n' character is added to the string.
* Few applications should need to override this method.
*/
METHODDEF(void)
format_message (j_common_ptr cinfo, char * buffer)
{
struct jpeg_error_mgr * err = cinfo->err;
int msg_code = err->msg_code;
const char * msgtext = NULL;
const char * msgptr;
char ch;
boolean isstring;
/* Look up message string in proper table */
if (msg_code > 0 && msg_code <= err->last_jpeg_message) {
msgtext = err->jpeg_message_table[msg_code];
} else if (err->addon_message_table != NULL &&
msg_code >= err->first_addon_message &&
msg_code <= err->last_addon_message) {
msgtext = err->addon_message_table[msg_code - err->first_addon_message];
}
/* Defend against bogus message number */
if (msgtext == NULL) {
err->msg_parm.i[0] = msg_code;
msgtext = err->jpeg_message_table[0];
}
/* Check for string parameter, as indicated by %s in the message text */
isstring = FALSE;
msgptr = msgtext;
while ((ch = *msgptr++) != '\0') {
if (ch == '%') {
if (*msgptr == 's') isstring = TRUE;
break;
}
}
/* Format the message into the passed buffer */
if (isstring)
sprintf(buffer, msgtext, err->msg_parm.s);
else
sprintf(buffer, msgtext,
err->msg_parm.i[0], err->msg_parm.i[1],
err->msg_parm.i[2], err->msg_parm.i[3],
err->msg_parm.i[4], err->msg_parm.i[5],
err->msg_parm.i[6], err->msg_parm.i[7]);
}
/*
* Reset error state variables at start of a new image.
* This is called during compression startup to reset trace/error
* processing to default state, without losing any application-specific
* method pointers. An application might possibly want to override
* this method if it has additional error processing state.
*/
METHODDEF(void)
reset_error_mgr (j_common_ptr cinfo)
{
cinfo->err->num_warnings = 0;
/* trace_level is not reset since it is an application-supplied parameter */
cinfo->err->msg_code = 0; /* may be useful as a flag for "no error" */
}
/*
* Fill in the standard error-handling methods in a jpeg_error_mgr object.
* Typical call is:
* struct jpeg_compress_struct cinfo;
* struct jpeg_error_mgr err;
*
* cinfo.err = jpeg_std_error(&err);
* after which the application may override some of the methods.
*/
GLOBAL(struct jpeg_error_mgr *)
jpeg_std_error (struct jpeg_error_mgr * err)
{
err->error_exit = error_exit;
err->emit_message = emit_message;
err->output_message = output_message;
err->format_message = format_message;
err->reset_error_mgr = reset_error_mgr;
err->trace_level = 0; /* default = no tracing */
err->num_warnings = 0; /* no warnings emitted yet */
err->msg_code = 0; /* may be useful as a flag for "no error" */
/* Initialize message table pointers */
err->jpeg_message_table = jpeg_std_message_table;
err->last_jpeg_message = (int) JMSG_LASTMSGCODE - 1;
err->addon_message_table = NULL;
err->first_addon_message = 0; /* for safety */
err->last_addon_message = 0;
return err;
}
#define JPEG_INTERNALS
#include "jpegint.h"
#define AM_MEMORY_MANAGER /* we define jvirt_Xarray_control structs */
#ifndef NO_GETENV
#ifndef HAVE_STDLIB_H /* <stdlib.h> should declare getenv() */
extern char * getenv JPP((const char * name));
#endif
#endif
/*
* Some important notes:
* The allocation routines provided here must never return NULL.
* They should exit to error_exit if unsuccessful.
*
* It's not a good idea to try to merge the sarray and barray routines,
* even though they are textually almost the same, because samples are
* usually stored as bytes while coefficients are shorts or ints. Thus,
* in machines where byte pointers have a different representation from
* word pointers, the resulting machine code could not be the same.
*/
/*
* Many machines require storage alignment: longs must start on 4-byte
* boundaries, doubles on 8-byte boundaries, etc. On such machines, malloc()
* always returns pointers that are multiples of the worst-case alignment
* requirement, and we had better do so too.
* There isn't any really portable way to determine the worst-case alignment
* requirement. This module assumes that the alignment requirement is
* multiples of sizeof(ALIGN_TYPE).
* By default, we define ALIGN_TYPE as double. This is necessary on some
* workstations (where doubles really do need 8-byte alignment) and will work
* fine on nearly everything. If your machine has lesser alignment needs,
* you can save a few bytes by making ALIGN_TYPE smaller.
* The only place I know of where this will NOT work is certain Macintosh
* 680x0 compilers that define double as a 10-byte IEEE extended float.
* Doing 10-byte alignment is counterproductive because longwords won't be
* aligned well. Put "#define ALIGN_TYPE long" in jconfig.h if you have
* such a compiler.
*/
#ifndef ALIGN_TYPE /* so can override from jconfig.h */
#define ALIGN_TYPE double
#endif
/*
* We allocate objects from "pools", where each pool is gotten with a single
* request to jpeg_get_small() or jpeg_get_large(). There is no per-object
* overhead within a pool, except for alignment padding. Each pool has a
* header with a link to the next pool of the same class.
* Small and large pool headers are identical except that the latter's
* link pointer must be FAR on 80x86 machines.
* Notice that the "real" header fields are union'ed with a dummy ALIGN_TYPE
* field. This forces the compiler to make SIZEOF(small_pool_hdr) a multiple
* of the alignment requirement of ALIGN_TYPE.
*/
typedef union small_pool_struct * small_pool_ptr;
typedef union small_pool_struct {
struct {
small_pool_ptr next; /* next in list of pools */
size_t bytes_used; /* how many bytes already used within pool */
size_t bytes_left; /* bytes still available in this pool */
} hdr;
ALIGN_TYPE dummy; /* included in union to ensure alignment */
} small_pool_hdr;
typedef union large_pool_struct * large_pool_ptr;
typedef union large_pool_struct {
struct {
large_pool_ptr next; /* next in list of pools */
size_t bytes_used; /* how many bytes already used within pool */
size_t bytes_left; /* bytes still available in this pool */
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